Title of Invention

"A Nucleic Acid Molecule of modified filovirus glycoprotein"

Abstract The invention is related to a nucleic acid molecule comprising a polynucleotide encoding a modified filovirus glycoprotein (GP) having at least one amino acid change located in a relatively conserved region of said GP that decreases in vitro cytotoxicity and retains immunogenicity when compared to in vitro cytotoxicity and immunogenicity of a wild type filovirus GP, and related modified filovirus GPs, plasmid DNAs, recombinant viruses, adenoviruses, pharmaceutical compositions, vaccine compositions, antibodies that are specifically reactive with the modified filovirus GPs, and related methods of making and using the same.
Full Text Related Applications
This application claims benefit of US Provisional Application No. 60/613,883 filed
September 27, 2004, US Provisional Application No. 60/677,606 filed May 03, 2005, US
Provisional Application No. 60/679,767 filed May 10, 2005, US Provisional Application
No. 60/701,694 filed July 22, 2005, and US Provisional Application No. 60/715,874 filed
September 9,2005, all of which are hereby incorporated by reference in then- entireties.
Field of the Invention
The present invention relates generally to viral vaccines and, more particularly, to
filovirus vaccines and methods of eliciting an immune response against a filovirus or a
disease caused by infection with filovirus.
Background of the Invention
Ebola virus and Marburg virus make up the family Filoviridae. The family is
divided into two genera, currently designated as "Ebola-like viruses" and "Marburg-like
viruses." There are four subtypes within the "Ebola-like viruses," Zaire (type species),
Sudan, Reston, and C6te d'lvoire (Ivory Coast). A single type, Marburg virus, makes up
the "Marburg-like viruses."
The glycoprotein (GP) is the sole structural protein making up the virion surface
spikes that mediate virus entry into susceptible host cells through receptor binding. GP is
the most studied of the filovirus proteins, not only for its importance in virus entry and
pathogenesis but because it is a prime target for vaccine development. Research on
filovirus GP has been facilitated through the use of recombinant DNA technology to permit
biochemical and functional assays without the constraints of working with the infectious
filovirus.
GP expression in cultured human endothelial and epithelial cells causes cell
rounding and detachment (Yang Z.-Y. et al. 2000 Nat Med 6:886-889). These effects
require the presence of the mucin-like serine and threonine -rich domain of GP. The
cytotoxic effects of GP on macrophage and endothelial cell function disrupt inflammatory
cell function and the integrity of the vasculature. In addition, by altering the cell surface
expression of adhesion proteins and immune recognition molecules, Ebola virus may
disrupt processes critical to immune activation and cytolytic-T-cell function. These
phenomena likely account for the dysregulation of the inflammatory response and the
vascular dysfunction characteristic of lethal Ebola virus infection, providing a rationale for
focusing on GP as a target for a preventative vaccine.
Summary of the Invention
The invention is related to a nucleic acid molecule comprising a polynucleotide
encoding a modified filovirus glycoprotein (GP) having at least one amino acid change
located in a relatively conserved region of said GP that decreases in vitro cytotoxicity and
retains immunogenicity when compared to in vitro cytotoxicity and immunogenicity of a
wild type filovirus GP.
In one embodiment, the amino acid change is positioned in the N-terminal domain,
excluding,the conserved cysteine residues, and is located at amino acid position 50, 51, 52,
53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76,
77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,100,
101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118,
119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136,
137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154,
155, 156, 157, 158, 159, 160, 161, 162,163, 164, 165, 166, 167, 168, 169, 170,171, 172,
173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190,
191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201,202, 203, 204, 205, 206, 207, 208,
209,210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226,
227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244,
245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255, 256, 257, 258, 259, 260, 261, 262,
263, 264, 265, 266, 267, 268, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280,
281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298,
299 or 300 in Ebola Zaire GP in an exemplary manner or corresponding thereto in other
strains of said GP.
In another embodiment, the amino acid change is located at amino acid position 71
or 102 in Ebola Zaire GP in an exemplary manner or corresponding thereto in other strains
of said GP.
In yet another embodiment, the amino acid change is E71D or G102A in Ebola
Zaire GP in an exemplary manner or corresponding thereto in other strains of said GP.
In still another embodiment, the modified filovirus GP is encoded by the insert of
SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:7
or SEQ ID NO:8, or sequence having at least 95% identity thereto.
In yet a further embodiment, the polynucleotide encoding the modified filovirus GP
has a sequence taken from the insert of SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ
ID NO:4, SEQ ID NO:6, SEQ ID NO:7, or SEQ ID NO:8, or sequence having at least 95%
identity thereto.
Other embodiments of the invention are related to modified filovirus GPs encoded
by the nucleic acid molecules, plasmid DNAs comprising the nucleic acid molecules,
recombinant viruses comprising the nucleic acid molecules, adenoviruses comprising the
nucleic acid molecules, pharmaceutical compositions comprising the nucleic acid
molecules or the modified filovirus GPs in a therapeutically effective dose, vaccine
compositions comprising the nucleic acid molecules or the modified filovirus GPs in a
prophylactically effective dose, antibodies that are specifically reactive with the modified
filovirus GPs, and related methods of making and using the same.
Brief Description of the Drawings
Figure 1. A) VRC6612 (pCMV/R-Ebola GP (S/G) (G to A)/h) construct map (see
human codon-optimized Ebola/Marburg plasmids in Table 2). B) Nucleotide sequence of
VRC6612(SEQIDNO: 1).
Figure 2. A) VRC6615 (pCMV/R-Ebola GP (Z) (full length G to A)/h) construct map
(see human codon-optimized Ebola/Marburg plasmids in Table 2). B) Nucleotide sequence of
VRC6615(SEQIDNO:2).
Figure 3. A) VRC6613 (pCMV/R-Ebola GP (S/G) (E to D)/h) construct map (see
human codon-optimized Ebola/Marburg plasmids in Table 2). B) Nucleotide sequence of
VRC6613(SEQIDNO:3).
Figure 4. A) VRC6616 (pCMV/R-Ebola GP (Z) (full length E to D)/h) construct map
(see human codon-optimized Ebola/Marburg plasmids in Table 2). B) Nucleotide sequence of
VRC6613(SEQIDNO:4).
Figure 5. A) VRC6712 (pCMV/R-Marburg/Angola GP/h) construct map (see human
codon-optimized Ebola/Marburg plasmids in Table 2). B) Nucleotide sequence of VRC6712
(SEQ ID NO: 5).
Figure 6. A) VRC6713 (pCMV/R Marburg/Angola GP (G102A)/h) construct map (see
human codon-optimized Ebola/Marburg plasmids in Table 2). B) Nucleotide sequence of
VRC6713(SEQIDNO:6).
Figure 7. A) pAdApt.Ebo.GP.FL.(Z).E71D (adenoviral adaptor plasmid-Ebola/Zaire
GP (full length E71D)/h). B) Nucleotide sequence of pAdApt.Ebo.GP.FL.(Z).E71D (SEQ ID
NO: 7). Upper case is the coding sequence Ebo.GP.FL.(Z).E71D, the boxed region shows the
E71D mutation and restriction site sequences used for cloning are bold and underlined.
Figure 8. A) pAdApt.Ebo.GP.FL.(S/G).E71D (adenoviral adaptor plasmid-
Ebola/(Sudan/Gulu) GP (full length E71D)/h). B) Nucleotide sequence of
pAdApt.Ebo.GP.FL.(S/G).E71D (SEQ ID NO: 8). Upper case is the coding sequence
Ebo.GP.FL.(S/G).E71D, the boxed region shows the E71D mutation and restriction site
sequences used for cloning are bold and underlined.
Figure 9. Schematic representation of Ebola virus GP. The GP1 and GP2 subunits of
GP are drawn to scale (residue numbers are indicated below the diagram). The positions of the
signal sequence, conserved cysteine residues (S), the mucin-like region (region of O-linked
glycosylation), the furin cleavage site, the fusion peptide, the coiled-coil domain, and the
membrane spanning domain are indicated.
Figure 10. Elimination of GP cytopathic effects and expression of transmembranedeleted
protein. A) Expression of GP(ATM) hi 293 cells. Ebola GP proteins from supernatants
and cell lysates in (A) were visualized by SDS- PAGE and Western blot using a polyclonal
antibody against Ebola GP. B) Elimination of cell rounding by GP(ATM). 293 cells were
transfected with a plasmid encoding vector control, Ebola GP or Ebola GP(ATM). Cell
monolayers were visualized under phase contrast using a Nikon 40X objective and
photographed at 24 hours post transfection.
Figure 11. Comparative efficacy of GP and GP(ATM) for protection against Ebola
virus challenge. A) Kaplan-Meier survival curve of macaques, immunized as indicated, and
challenged with 1000 PFU of Ebola virus (1995 Zaire subtype) one month post immunization.
The x-axis indicates weeks post-challenge. n=3 in different immunization groups except for
the GP(Z)+NP (1012) group, n=4, and Control, n=l. B) Immune responses in immunized
animals. Left and middle panels: intracellular flow cytometry was performed to quantify TNFcc
production from Ebola-specific CD4+ or CDS* lymphocytes, respectively, from animals
immunized as indicated. Immune responses were measured at 3 weeks post-immunization.
Circle, diamond, square, triangle: responses for individual animals. Horizontal line: average of
individual responses in the immunization group. Results represent the percent cytokine
positive in the gated lymphocyte group and background stimulation (DMSO alone) has been
subtracted from each sample. Right panel: ELISA titers of Ebola GP-specific antibodies in
serum of vaccinated animals collected at week 3 post-immunization. ELISA results represent
endpoint dilution liters determined by optical density as described in Example 1.
Figure 12. Determination of lowest vaccine dose for immune protection against Ebola
virus challenge by adenoviral vector vaccine. A) Kaplan-Meier survival curve of macaques:
immunization and challenge were performed with the 1995 Zaire subtype Ebola virus as in Fig.
11 A. B) Immune responses in immunized animals. Intracellular flow cytometry was
performed to quantify TNF-a production from Ebola-specific CD4 (left panel) or CDS (right
panel) lymphocytes, respectively, from animals immunized as indicated. Immune responses
were measured at 3 weeks post-immunization. Circle, diamond, square: responses for
individual animals. Horizontal line: average of individual responses in the immunization
group. Results represent the percent cytokine positive in the gated lymphocyte group and
background stimulation (DMSO alone) has been subtracted from each sample (p-values
obtained using unpaired Student's t-test. n. s. = not significant). C) Antibody responses in
immunized animals. Anti-GP ELISA titers (left panel) and serum neutralizing antibody
responses (right panel) were measured as described in Example 1.
Figure 13. Comparative efficacy of wild type and point mutant glycoprotein vaccines
against lethal Ebola virus challenge. A) Kaplan-Meier survival curve of macaques:
immunization and challenge were performed with the 1995 Zaire subtype Ebola virus as in Fig.
11 A. B) Immune responses in immunized animals. Left and middle panels: intracellular flow
cytometry was performed to quantify TNF-a production from Ebola-specific CD4 or CDS
lymphocytes, respectively, from animals immunized as indicated. Immune responses were
measured at 3 weeks post-immunization. Circle, diamond, square: responses for individual
animals. Horizontal line: average of individual responses hi the immunization group. Results
represent the percent cytokine positive in the gated lymphocyte group and background
stimulation (DMSO alone) has been subtracted from each sample. Right panel: ELISA titers of
Ebola GP-specific antibodies in serum of vaccinated animals collected at week 3 postimmunization,
ELISA results represent endpoint dilution titers determined by optical density
as described in Example 1.
Figure 14. Elimination of GP cytopathic effects with single point mutation.
A) Expression of point mutants in 293 cells. Ebola GP proteins from supernatants and cell
lysates in (A) were visualized by SDS- PAGE and Western blot using a polyclonal antibody
against Ebola GP. B) Reactivity of point mutants with a conformation-dependent antibody.
293 cells were transfected with a control plasmid (Con), or plasmids expressing wild type
(GP(Z)) or mutant (E71D(Z)) proteins. Eighteen hours post-transfection, cells were harvested,
stained with a GP-specific antibody and cell surface GP expression was analyzed by flow
cytometry. C) Elimination of cell rounding by amino acid substitution at position 71. 293
cells were transfected with a plasmid encoding vector control, wild type Ebola glycoprotein
from Zaire (GP(Z)) or Sudan-Gulu (GP(S/G)) or their respective point mutations (E71D(Z)),
E71D(S/G)). Cell monolayers were visualized under phase contrast using a Nikon 40X
objective and photographed at 24 hours post transfection.
Figure 15. Cellular immune responses generated in NHP immunized with GP(Z)
E71D/NP.
Figure 16. Humoral immune responses generated in NHP immunized with GP(Z)
E71D/NP.
Figure 17. Comparative efficacy of wild type GP vs. point mutant immunogens.
Figure 18. Elimination of GP cytopathic effects with single point mutation.
Elimination of cell rounding by amino acid substitution at position 71 or 102. 293 cells were
transfected with a plasmid encoding vector control, wildtype Ebola Zaire glycoprotein, WT
GP, or point mutations 71E/D, 102G/A, 138V/A or a mutation in which the transmembrane
domain is deleted, ATM. Cell monolayers were visualized under phase contrast using a Nikon
40X objective and photographed at 24 hours post transfection. Cell rounding is eliminated
with mutation at residue 71 or 102, and with transmembrane deletion.
Figure 19. Single point mutation in GP and retention of reactivity with neutralizing
antibodies. Reactivity of point mutants with a conformation-dependent antibody. 293 cells
were transfected with a control plasmid, dashed line, or plasmids expressing wildtype Ebola
GP (WT GP) or mutant (71E/D 102G/A), solid line, proteins. Eighteen hours post transfection,
cells were harvested, stained with a GP-specific neutralizing antibody and cell surface GP
expression was analyzed by flow cytometry.
Figure 20. Ebola Zaire GP amino acid sequence (SEQ ID NO: 9).
(Table Removed)
Detailed Description of the Preferred Embodiment
In the absence of effective therapies for Ebola virus infection, the development of a
vaccine becomes an important strategy to contain outbreaks. Immunization with DNA
and/or replication-defective adenoviral (rAd) vectors encoding the Ebola glycoprotein (GP)
and nucleoprotein (NP) has been previously shown to confer specific protective immunity
in nonhuman primates (Sullivan, N. J. et al. 2000 Nature 408:605-609; Sullivan, N. J. et al.
2003 Nature 424:681-684). GP can exert cytopathic effects on transfected cells in vitro
(Yang, Z.-Y. et al. 2000 NatMed 6:886-889) and multiple GP forms have been identified in
nature, raising the question of which would be optimal for a human vaccine. To address
this question, we have explored the efficacy of mutant GPs from multiple Ebola virus
strains with reduced in vitro cytopathicity and analyzed their protective effects in the
primate challenge model, with or without NP. Deletion of the GP transmembrane domain
eliminated in vitro cytopathicity but reduced its protective efficacy by at least one order of
magnitude. In contrast, single point mutations were identified that abolish in vitro
cytopathicity but retained immunogenicity and conferred immune protection in the absence
of NP. The minimal effective rAd dose was established at 1010 particles, two logs lower
than used previously. Expression of specific GPs alone vectored by rAd are sufficient to
confer protection against lethal challenge in a relevant nonhuman primate model, providing
the basis for identification of a vaccine.
Definitions
Unless defined otherwise, technical and scientific terms used herein have the same
meaning as commonly understood by one of ordinary skill in the art to which this invention
belongs. See, e.g., Singleton P and Sainsbury D., Dictionary of Microbiology and
Molecular Biology 3rd ed., J. Wiley & Sons, Chichester, New York, 2001, and Fields
Virology 4th ed., Knipe D.M. and Howley P.M. eds, Lippincott Williams & Wilkins,
Philadelphia 2001.
Nucleic Acid Molecules
As indicated herein, nucleic acid molecules of the present invention may be in the
form of RNA or in the form of DNA obtained by cloning or produced synthetically. The
DNA may be double-stranded or single-stranded. Single-stranded DNA or RNA may be
the coding strand, also known as the sense strand, or it may be the non-coding strand, also
referred to as the anti-sense strand.
By "isolated" nucleic acid molecule(s) is intended a nucleic acid molecule, DNA or
RNA, which has been removed from its native environment. For example, recombinant
DNA molecules contained in a vector are considered isolated for the purposes of the
present invention. Further examples of isolated DNA molecules include recombinant DNA
molecules maintained in heterologous host cells or purified (partially or substantially) DNA
molecules in solution. Isolated RNA molecules include in vivo or in vitro RNA transcripts
of the DNA molecules of the present invention. Isolated nucleic acid molecules according
to the present invention further include such molecules produced synthetically.
Nucleic acid molecules of the present invention include DNA molecules comprising
an open reading frame (ORF) encoding a modified filovirus structural gene product; and
DNA molecules which comprise a sequence substantially different from those described
above but which, due to the degeneracy of the genetic code, still encode an ORF of a
modified filovirus structural gene product. Of course, the genetic code is well known in the
art. Degenerate variants optimized for human codon usage are preferred.
A filovirus structural gene product, e.g., glycoprotein (GP), the sole structural
protein making up the virion surface spikes that mediate virus entry into susceptible host
cells through receptor binding, is modified by having at least one amino acid change that
decreases in vitro cytotoxicity and retains immunogenicity when compared to in vitro
cytotoxicity and immunogenicity of a wild type (e.g., naturally occurring) filovirus GP.
The amino acids of particular importance to the in vitro cytotoxicity are by no means
limited to the exact position as defined for the, e.g., Zaire strain of Ebola virus but are
simply used in an exemplary manner to point out the preferred amino acids being at that
position or corresponding to that position in other strains such as found in Sudan strain of
Ebola virus or Angola strain of Marburg virus and filoviruses in general since they are
highly conserved. For filoviruses other than the Ebola Zaire strain the numbering of the
positions of the preferred amino acids is often different but an expert in the field of the
molecular biology of filoviruses will easily identify these preferred amino acids by their
position relative to the highly conserved amino acids of said glycoprotein.
The present invention is further directed to fragments of the nucleic acid molecules
described herein. By a fragment of a nucleic acid molecule having the nucleotide sequence
of an ORF encoding a modified filovirus structural gene product is intended fragments at
least about 15 nt, and more preferably at least about 20 nt., still more preferably at least
about 30 nt., and even more preferably, at least about 40 nt. in length. Of course, larger
fragments 50,100, 150, 200, 250, 300, 350,400,450, or 500 nt. in length are also intended
according to the present invention as are fragments corresponding to most, if not all, of the
nucleotide sequence of the ORF encoding a modified filovirus structural gene product. By
a fragment at least 20 nt. in length, for example, is intended fragments which include 20 or
more contiguous bases from the nucleotide sequence of the ORF encoding a modified
filovirus structural gene product.
Preferred nucleic acid fragments of the present invention include nucleic acid
molecules encoding epitope-bearing portions of the filovirus structural protein. In
particular, such nucleic acid fragments of the present invention include nucleic acid
molecules encoding epitope-bearing domains of a filovirus structural protein, where the
domain is the N-terminal domain, the mucin-like domain, the furin cleavage site, the fusion
peptide domain, the coiled-coli domain, the membrane spanning domain, and the
intracellular domain, and any combination thereof, for example, a filovirus glycoprotein
having a truncation at the carboxy terminus to delete the membrane spanning and
intracellular domain, a filovirus glycoprotein having a truncation at the carboxy terminus to
delete the coiled-coil domain and membrane-spanning and intracellular domain, a filovirus
glycoprotein having a truncation at the carboxy terminus to delete the fusion peptide
domain, coiled-coil domain, and membrane-spanning and intracellular domain, a filovirus
glycoprotein having a truncation at the carboxy terminus to delete the furin cleavage site,
fusion peptide domain, coiled-coil domain, and membrane-spanning and intracellular
domain, a filovirus glycoprotein having a truncation at the carboxy terminus to delete the
mucin-like domain, furin cleavage site, fusion peptide domain, coiled-coil domain, and
membrane-spanning and intracellular domain. Another example is a filovirus glycoprotein
having an amino, internal, or carboxy deletion to delete the mucin-like domain, the furin
cleavage site, the fusion peptide domain, the coiled-coil domain, the membrane-spanning
domain, or the intracellular domain.
In another aspect, the invention provides a nucleic acid molecule comprising a
polynucleotide which hybridizes under stringent hybridization conditions to a portion of the
polynucleotide in a nucleic acid molecule of the invention described above. By "stringent
hybridization conditions" is intended overnight incubation at 42°C in a solution
comprising: 50% formamide, 5 x SSC (750 mM NaCl, 75 mM trisodium citrate), 50 mM
sodium phosphate (pH 7.6), 5 x Denhardt's solution, 10% dextran sulfate, and 20 }j,g/ml
denatured, sheared salmon sperm DNA, followed by washing the filters in 0.1 x SSC at
about 65°C.
By a polynucleotide which hybridizes to a "portion" of a polynucleotide is intended
a polynucleotide (either DNA or RNA) hybridizing to at least about 15 nucleotides (nt),
and more preferably at least about 20 nt., still more preferably at least about 30 nt, and
even more preferably about 30-70 nt. of the reference polynucleotide.
By a portion of a polynucleotide of "at least 20 nt. in length," for example, is
intended 20 or more contiguous nucleotides from the nucleotide sequence of the reference
polynucleotide. Of course, a polynucleotide which hybridizes only to a poly A sequence or
a complementary stretch of T (or U) residues, would not be included in a polynucleotide of
the invention used to hybridize to a portion of a nucleic acid of the invention, since such a
polynucleotide would hybridize to any nucleic acid molecule containing a poly A stretch or
the complement thereof (e.g., practically any double-stranded cDNA clone).
As indicated herein, nucleic acid molecules of the present invention which encode a
filo virus structural gene product may include, but are not limited to those encoding the
amino acid sequence of the full-length polypeptide, by itself, the coding sequence for the
full-length polypeptide and additional sequences, such as those encoding a leader or
secretory sequence, such as a pre-, or pro- or prepro-protein sequence, the coding sequence
of the full-length polypeptide, with or without the aforementioned additional coding
sequences, together with additional, non-coding sequences, including for example, but not
limited to introns and non-coding 5' and 3' sequences, such as the transcribed, nontranslated
sequences that play a role in transcription, mRNA processing, including splicing
and polyadenylation signals, for example, ribosome binding and stability of mRNA; and
additional coding sequence which codes for additional amino acids, such as those which
provide additional functionalities.
The present invention further relates to variants of the nucleic acid molecules of the
present invention, which encode portions, analogs or derivatives of the filovirus structural
gene product. Variants may occur naturally, such as a natural allelic variant. By an "allelic
variant" is intended one of several alternate forms of a gene occupying a given locus on a
genome of an organism. (Genes II, Lewin, B., ed., John Wiley & Sons, 1985 New York).
Non-naturally occurring variants may be produced using art-known mutagenesis
techniques.
Such variants include those produced by nucleotide substitutions, deletions or
additions, which may involve one or more nucleotides. The variants may be altered in
coding regions, non-coding regions, or both. Alterations in the coding regions may produce
conservative or non-conservative amino acid substitutions, deletions or additions.
Especially preferred among these are silent substitutions, additions and deletions, which do
not alter the properties and activities of the filovirus structural gene product or portions
thereof. Also especially preferred in this regard are conservative substitutions.
Further embodiments of the invention include nucleic acid molecules comprising a
polynucleotide having a nucleotide sequence at least 95% identical, and more preferably at
least 96%, 97%, 98% or 99% identical to a nucleotide sequence encoding a polypeptide
having the amino acid sequence of a modified filovirus structural gene product or fragment
thereof or a nucleotide sequence complementary thereto.
By a polynucleotide having a nucleotide sequence at least, for example, 95%
"identical" to a reference nucleotide sequence encoding a filovirus structural gene product
is intended that the nucleotide sequence of the polynucleotide is identical to the reference
sequence except that the polynucleotide sequence may include up to five point mutations
per each 100 nucleotides of the reference nucleotide sequence encoding the Ebola virus
structural gene product, hi other words, to obtain a polynucleotide having a nucleotide
sequence at least 95% identical to a reference nucleotide sequence, up to 5% of the
nucleotides in the reference sequence maybe deleted or substituted with another nucleotide,
or a number of nucleotides up to 5% of the total nucleotides in the reference sequence may
be inserted into the reference sequence. These mutations of the reference sequence may
occur at the 5' or 3' terminal positions of the reference nucleotide sequence or anywhere
between those terminal positions, interspersed either individually among nucleotides in the
reference sequence or in one or more contiguous groups within the reference sequence.
As a practical matter, whether any particular nucleic acid molecule is at least 95%,
96%, 97%, 98% or 99% identical to the reference nucleotide sequence can be determined
conventionally using known computer programs such as the Bestfit program (Wisconsin
Sequence Analysis Package, Version 8 for Unix, Genetics Computer Group, University
Research Park, 575 Science Drive, Madison, Wis. 53711). Bestfit uses the local homology
algorithm of Smith and Waterman 1981 Advances in Applied Mathematics 2:482-489, to
find the best segment of homology between two sequences. When using Bestfit or any
other sequence alignment program to determine whether a particular sequence is, for
instance, 95% identical to a reference sequence according to the present invention, the
parameters are set, of course, such that the percentage of identity is calculated over the full
length of the reference nucleotide sequence and that gaps in homology of up to 5% of the
total number of nucleotides in the reference sequence are allowed.
The present application is directed to nucleic acid molecules at least 95%, 96%,
97%, 98% or 99% identical to the nucleic acid sequences described herein which encode a
polypeptide having Ebola or Marburg polypeptide activity. By "a polypeptide having Ebola
or Marburg, polypeptide activity" is intended polypeptides exhibiting Ebola or Marburg
polypeptide activity in a particular biological assay. For example, GP polypeptide activity
can be measured for changes in biological activity such as receptor binding activity,
connection between GPI and GP2, and contribution to the formation of the stalk structure
of the virion peplomer, and modified GP polypeptide activity by decrease of in vitro
cytotoxicity while retaining immunogenicity.
Of course, due to the degeneracy of the genetic code, one of ordinary skill in the art
will immediately recognize that a large number of the nucleic acid molecules having a
sequence at least 95%, 96%, 97%, 98%, or 99% identical to a nucleic acid sequence
described herein will encode a polypeptide "having Ebola or Marburg polypeptide activity".
In fact, since degenerate variants of these nucleotide sequences all encode the same
polypeptide, this will be clear to the skilled artisan even without performing the above
described comparison assay. It will be further recognized in the art that, for such nucleic
acid molecules that are not degenerate variants, a reasonable number will also encode a
polypeptide having Ebola or Marburg polypeptide activity. This is because the skilled
artisan is fully aware of amino acid substitutions that are either less likely or not likely to
significantly effect protein function (e.g., replacing one aliphatic amino acid with a second
aliphatic amino acid).
For example, guidance concerning how to make phenotypically silent amino acid
substitutions is provided in Bowie, J. U. et al. 1990 Science 247:1306-1310, wherein the
authors indicate that proteins are surprisingly tolerant of amino acid substitutions.
Polypeptides and Fragments
The invention further provides a filovirus polypeptide having the amino acid
sequence encoded by an open reading frame (ORF) of a modified filovirus structural gene,
or a peptide or polypeptide comprising a portion thereof (e.g., soluble GP).
It will be recognized in the art that some amino acid sequences of the filovirus
polypeptides can be varied without significant effect of the structure or function of the
protein. If such differences hi sequence are contemplated, it should be remembered that
there will be critical areas on the protein which determine activity.
Thus, the invention further includes variations of the filovirus polypeptide which
show substantial filovirus polypeptide activity or which include regions of filovirus protein
such as the protein portions discussed below. Such mutants include deletions, insertions,
inversions, repeats, and type substitutions. As indicated, guidance concerning which amino
acid changes are likely to be phenotypically silent can be found in Bowie, J.U. et al. 1990
Science 247:1306-1310.
Thus, the fragment, derivative or analog of the polypeptide of the invention may be
(i) one in which one or more of the amino acid residues are substituted with a conserved or
non-conserved amino acid residue (preferably a conserved amino acid residue) and such
substituted amino acid residue may or may not be one encoded by the genetic code, or (ii)
one in which one or more of the amino acid residues include a substituent group, or (iii) one
in which additional amino acids are fused to the mature polypeptide, such as an IgG Fc
fusion region peptide or leader or secretory sequence or a sequence which is employed for
purification of the mature polypeptide or a proprotein sequence. Such fragments,
derivatives and analogs are deemed to be within the scope of those skilled in the art from
the teachings herein.
As indicated, changes are preferably of a minor nature, such as conservative amino
acid substitutions that do not significantly affect the folding or activity of the protein (see
Table A).
(Table Removed)
Of course, the number of amino acid substitutions a skilled artisan would make
depends on many factors, including those described above. Generally speaking, the number
of amino acid substitutions for any given filovirus polypeptide will not be more than 50,40,
30, 20,10, 5 or 3.
Amino acids in the filovirus polypeptides of the present invention that are essential
for function can be identified by methods known in the art, such as site-directed
mutagenesis or alanine-scanning mutagenesis (Cunningham & Wells 1989 Science
244:1081-1085). The latter procedure introduces single alanine mutations at every residue
in the molecule. The resulting mutant molecules are then tested for biological activity such
as receptor binding activity, connection between GP1 and GP2, and contribution to the
formation of the stalk structure of the virion peplomer, and modified GP polypeptide
activity by decrease of in vitro cytotoxicity while retaining immunogenicity.
The polypeptides of the present invention are conveniently provided in an isolated
form. By "isolated polypeptide" is intended a polypeptide removed from its native
environment. Thus, a polypeptide produced and/or contained within a recombinant host
cell is considered isolated for purposes of the present invention. Also intended as an
"isolated polypeptide" are polypeptides that have been purified, partially or substantially,
from a recombinant host cell or a native source. For example, a recombinantly produced
version of the filovirus polypeptide can be substantially purified by the one-step method
described in Smith and Johnson 1988 Gene 67:31-40.
The polypeptides of the present invention include a polypeptide comprising a
polypeptide having the amino acid sequence of a modified filovirus structural gene product
or portion thereof or encoded by a nucleic acid sequence described herein; as well as
polypeptides which are at least 95% identical, and more preferably at least 96%, 97%, 98%,
or 99% identical to those described above and also include portions of such polypeptides
with at least 30 amino acids and more preferably at least 50 amino acids.
By a polypeptide having an amino acid sequence at least, for example, 95%
"identical" to a reference amino acid sequence of an filovirus polypeptide is intended that
the amino acid sequence of the polypeptide is identical to the reference sequence except
that the polypeptide sequence may include up to five amino acid alterations per each 100
amino acids of the reference amino acid of the filovirus polypeptide. In other words, to
obtain a polypeptide having an amino acid sequence at least 95% identical to a reference
amino acid sequence, up to 5% of the amino acid residues in the reference sequence may be
deleted or substituted with another amino acid, or a number of amino acids up to 5% of the
total amino acid residues in the reference sequence may be inserted into the reference
sequence. These alterations of the reference sequence may occur at the amino or carboxy
terminal positions of the reference amino acid sequence or anywhere between those
terminal positions, interspersed either individually among residues in the reference
sequence or in one or more contiguous groups within the reference sequence.
As a practical matter, whether any particular polypeptide is at least 95%, 96%, 97%,
98%, or 99% identical to a reference amino acid sequence can be determined
conventionally using known computer programs such the Bestfit program (Wisconsin
Sequence Analysis Package, Version 8 for Unix, Genetics Computer Group, University
Research Park, 575 Science Drive, Madison, Wis. 53711). When using Bestfit or any other
sequence alignment program to determine whether a particular sequence is, .for instance,
95% identical to a reference sequence according to the present invention, the parameters are
set, of course, such that the percentage of identity is calculated over the full length of the
reference amino acid sequence and that gaps in homology of up to 5% of the total number
of amino acid residues hi the reference sequence are allowed.
In another aspect, the invention provides portions of the polypeptides described
herein with at least 30 amino acids and more preferably at least 50 amino acids. Preferred
portions of the present invention include polypeptides comprising an epitope-bearing
portion of a filovirus structural protein. In particular, preferred portions of the present
invention include polypeptides comprising an epitope-bearing domain of a filovirus
structural protein, where the domain is the N-terminal domain, the mucin-like domain, the
furin cleavage site, the fusion peptide domain, the coiled-coil domain, the membranespanning
domain, and the intracellular domain, and any combination thereof, for example, a
filovirus glycoprotein having a truncation at the carboxy terminus to delete the membrane
spanning and intracellular domain, a filovirus glycoprotein having a truncation at the
carboxy terminus to delete the coiled-coil domain and membrane spanning and intracellular
domain, a filovirus glycoprotein having a truncation at the carboxy terminus to delete the
fusion peptide domain, coiled-coil domain, and membrane-spanning and intracellular
domain, a filovirus glycoprotein having a truncation at the carboxy terminus to delete the
furin cleavage site, fusion peptide domain, coiled-coil domain, and membrane-spanning and
intracellular domain, and a filovirus glycoprotein having a truncation at the carboxy
terminus to delete the mucin-like domain, furin cleavage site, fusion peptide domain,
coiled-coil domain, and membrane-spanning and intracellular domain. Another example is
a filovirus glycoprotein having an amino, internal, or carboxy deletion to delete the mucinlike
domain, the furin cleavage site, the fusion peptide domain, the coiled-coil domain, the
membrane-spanning domain, or the intracellular domain.
The polypeptides of the invention may be produced by any conventional means
(Houghten, R.A. 1985 PNAS USA 82:5131-5135). The "Simultaneous Multiple Peptide
Synthesis (SMPS)" process is described in U.S. Pat. No. 4,631,211 to Houghten et al.
(1986).
The present invention also relates to vectors which include the nucleic acid
molecules of the present invention, host cells which are genetically engineered with the
recombinant vectors, and the production of filovirus polypeptides or fragments thereof by
recombinant techniques.
The polynucleotides may be joined to a vector containing a selectable marker for
propagation in a host. Generally, a plasmid vector is introduced in a precipitate, such as a
calcium phosphate precipitate, or in a complex with a charged lipid. If the vector is a virus,
it may be packaged in vitro using an appropriate packaging cell line and then transduced
into host cells.
The DNA insert should be operatively linked to an appropriate promoter, such as
the phage lambda PL promoter, the E. coli lac, trp and tac promoters, the SV40 early and
late promoters and promoters of retroviral LTRs, to name a few. Other suitable promoters
will be known to the skilled artisan. The expression constructs will further contain sites for
transcription initiation, termination and, in the transcribed region, a ribosome binding site
for translation. The coding portion of the mature transcripts expressed by the constructs
will preferably include a translation initiation at the beginning and a termination codon
(UAA, UGA or UAG) appropriately positioned at the end of the polypeptide to be
translated.
As indicated, the expression vectors will preferably include at least one selectable
marker. Such markers include dihydrofolate reductase or neomycin resistance for
eukaryotic cell culture and tetracycline or ampicillin resistance genes for culturing E. coli
and other bacteria. Representative examples of appropriate hosts include, but are not
limited to, bacterial cells, such as E. coli, Streptomyces and Salmonella typhimurium cells;
fungal cells, such as yeast cells; insect cells such as Drosophila S2 and Spodoptera Sf9
cells; animal cells such as CHO, COS and Bowes melanoma cells; and plant cells.
Appropriate culture mediums and conditions for the above-described host cells are known
in the art.
Among vectors preferred for use hi bacteria include pQE70, pQE60, and pQE-9,
available from Qiagen; pBS vectors, Phagescript vectors, Bluescript vectors, pNHSA,
pNH16a, pHN18A, pNH46A, available from Stratagene; and ptrc99a, pKK223-3, pKK233-
3, pDR540, pRITS available from Pharmacia. Among preferred eukaryotic vectors are
pWLNEO, pSV2CAT, pOG44, pXTl and pSG available from Stratagene; and pSVK3,
pBPV, pMSG and pSVL available from Pharmacia. Other suitable vectors will be readily
apparent to the skilled artisan.
Introduction of the construct into the host cell can be effected by calcium phosphate
transfection, DEAE-dextran mediated transfection, cationic lipid-mediated transfection,
electroporation, transduction, infection or other methods. Such methods are described hi
many standard laboratory manuals, such as Davis et al., Basic Methods hi Molecular
Biology (1986).
The filovirus polypeptides can be recovered and purified from recombinant cell
cultures by well known methods including ammonium sulfate or ethanol precipitation, acid
extraction, anion or cation exchange chromatography, phosphocellulose chromatography,
hydrophobic interaction chromatography, affinity chromatography, hydroxylapatite
chromatography and lectin chromatography. Most preferably, high performance liquid
chromatography ("HPLC") is employed for purification. Polypeptides of the present
invention include naturally purified products, products of chemical synthetic procedures,
and products produced by recombinant techniques from a prokaryotic or eukaryotic host,
including, for example, bacterial, yeast, higher plant, insect and mammalian cells.
Depending upon the host employed in a recombinant production procedure, the
polypeptides of the present invention may be glycosylated or may be non-glycosylated. In
addition, polypeptides of the invention may also include an initial modified methionine
residue, in some cases as a result of host-mediated processes.
Antibodies
Also comprehended by the present invention are antibodies (e.g., monoclonal and
polyclonal antibodies, single-chain antibodies, chimeric antibodies, humanized, human, and
CDR-grafted antibodies, including compounds which include CDR sequences which
specifically recognize a polypeptide of the invention) and other binding proteins specific for
filovirus GP polypeptides or fragments thereof. The term "specific for" indicates that the
variable regions of the antibodies of the invention recognize and bind a filovirus GP
polypeptide exclusively (i.e., are able to distinguish a filovirus GP polypeptide from related
polypeptides despite sequence identity, homology, or similarity found in the family of
polypeptides), but may also interact with other proteins through interactions with sequences
outside the variable region of the antibodies, and in particular, in the constant region of the
molecule. Screening assays to determine binding specificity of an antibody of the invention
are well known and routinely practiced in the art. For a comprehensive discussion of such
assays, see Antibodies A Laboratory Manual. Harlow et al. (Eds), Cold Spring Harbor
Laboratory; Cold Spring Harbor, NY (1988), Chapter 6. Antibodies that recognize and
bind fragments of the filovirus GP polypeptides of the invention are also contemplated,
provided that the antibodies are first and foremost specific for, as defined above, a filovirus
GP polypeptide of the invention from which the fragment was derived. The specific
antibodies of the invention are envisioned as having utility for diagnostic purposes and
passive immunization.
Use of Recombinant Virus to Induce Immune Response to Antigen
The present invention relates to generation of a CD8+ T cell immune response
against an antigen and also eliciting an antibody response. More particularly, the present
invention relates to "accelerated" immunization regimes in which the immune response is
induced by administration of a single dose form and "prime and boost" immunization
regimes in which the immune response induced by administration of a priming composition
is boosted by administration of a boosting composition. The present invention, in one
embodiment, is based on the inventors' experimental demonstration that effective
immunization can be achieved using recombinant virus, e.g., adenovirus, optionally as
boosting compositions following priming with any of a variety of different types of priming
compositions.
A major protective component of the immune response against a number of
pathogens is mediated by T lymphocytes of the CD8+ type, also known as cytotoxic T
lymphocytes (CTL). An important function of CD8+ cells is secretion of gamma interferon
(IFNy), and this provides a measure of CD8+ T cell immune response. A second
component of the immune response is antibody directed to the proteins of the pathogen.
The present invention, in one embodiment, employs recombinant virus, e.g.,
adenovirus, which, as the experiments described below show, has been found to be an
effective means for inducing a CD8+ T cell immune response, optionally as a boosting
composition primed by antigen using any of a variety of different priming compositions,
and for eliciting an antibody response.
Replication-deficient adenovirus derived from human serotype 5 has been
developed as a live viral vector by Graham and colleagues (Graham & Prevec 1995 Mol
Biotechnol 3:207-20; Bett et al. 1994 PNAS USA 91:8802-6). Adenoviruses are nbnenveloped
viruses containing a linear double-stranded DNA genome of around 36 kb.
Recombinant viruses can be constructed by in vitro recombination between an adenovirus
genome plasmid and a shuttle vector containing the gene of interest together with a strong
eukaryotic promoter, in a permissive cell line which allows viral replication. High viral
titres can be obtained from the permissive cell line, but the resulting viruses, although
capable of infecting a wide range of cell types, do not replicate in any cells other than the
permissive line, and are therefore a safe antigen delivery system. Recombinant
adenovirases have been shown to elicit protective immune responses against a number of
antigens including tick-borne encephalitis virus NS1 protein (Jacobs et al. 1992 J Virol
66:2086-95) and measles virus nucleoprotein (Fooks et al. 1995 Virology 210:456-65).
Remarkably, the experimental work described below demonstrates that use of
embodiments of the present invention allows for recombinant adenovirus expressing an
antigen to induce an immune response, optionally as a boosting composition primed by a
DNA vaccine. The adenovirus was found to induce an immune a CD8+ T cell and antibody
response after intramuscular immunization. In prime/boost vaccination regimes the
recombinant virus, e.g., adenovirus, is also envisioned as being able to prime an immune
response that can be boosted by a different recombinant virus or recombinantly produced
antigen.
Non-human primates immunized with recombinant virus, e.g., adenovirus,
optionally as a boosting composition following priming with plasmid DNA were protected
against challenge. Both recombinant adenovirus and plasmid DNA are vaccines that are
safe.for use in humans., Advantageously, the inventors found that a vaccination regime
using single dose immunization, optionally prime and boost immunization, can be
employed, constituting a general immunization regime suitable for inducing an immune
response, e.g., in humans.
The present invention in various aspects and embodiments employs a recombinant
virus, e.g., adenovirus, encoding an antigen for inducing an immune response to the
antigen, optionally for boosting an immune response primed by previous administration of
the antigen or nucleic acid encoding the antigen.
A general aspect of the present invention provides for the use of a recombinant
virus, e.g., adenovirus, for inducing, optionally boosting an unmune response to an antigen.
One aspect of the present invention provides a method of inducing, optionally
boosting an immune response to an antigen in an individual, the method including
provision in the individual of a recombinant virus, e.g., adenovirus, including nucleic acid
encoding the antigen operably linked to regulatory sequences for production of antigen in
the individual by expression from the nucleic acid, whereby an immune response to the
antigen is induced or an immune response to the antigen previously primed in the
individual is boosted.
An immune response to an antigen may be primed by plasmid DNA immunization,
by infection with an infectious agent, or by development of a recombinantly produced
antigen.
2-3
A further aspect of the invention provides a method of inducing an immune
response to an antigen in an individual, the method comprising administering to the
individual a single dose of composition comprising the antigen or nucleic acid encoding the
antigen or a priming composition comprising the antigen or nucleic acid encoding the
antigen and then administering a boosting composition which comprises a recombinant
virus, e.g., adenovirus, including nucleic acid encoding the antigen operably linked to
regulatory sequences for production of antigen in the individual by expression from the
nucleic acid.
A further aspect provides for use of a recombinant virus, e.g., adenovirus, as
disclosed, in the manufacture of a medicament for administration to a mammal to induce,
optionally to boost an immune response to an antigen. Such a medicament is optionally for
administration in single dose form or following prior administration of a priming
composition comprising the antigen or nucleic acid encoding the antigen.
The inducing, boosting, or priming composition may comprise any viral vector,
including adenoviral, or other than adenoviral, such as a vaccinia virus vector such as a
replication-deficient strain such as modified virus Ankara (MVA) (Mayr et al. 1978
Zentralbl Bakteriol 167:375-90; Sutter and Moss 1992 PNAS USA 89:10847-51; Sutter et
al. 1994 Vaccine 12:1032-40) or NYVAC (fartaglia et al. 1992 Virology 118:217-32), an.
avipox vector such as fowlpox or canarypox, e.g., the strain known as ALVAC (Kanapox,
Paoletti et al. 1994 Dev Biol Stand 82:65-9), a herpes virus vector, a vesicular stomatitis
virus vector, or an alphavirus vector.
The inducing or priming composition may comprise DNA encoding the antigen,
such DNA preferably being in the form of a circular plasmid that is not capable of
replicating in mammalian cells. Any selectable marker should not be resistant to an
antibiotic used clinically, so for example Kanamycin resistance is preferred to Ampicillin
resistance. Antigen expression should be driven by a promoter which is active in
mammalian cells, for instance the cytomegalovirus immediate early (CMV IE) promoter.
In particular, prime and boost embodiments of the various aspects of the present
invention, administration of a priming composition is followed by boosting with a boosting
composition or first and second boosting compositions, the first and second boosting
compositions being the same or different from one another. Still further boosting
compositions may be employed without departing from the present invention. In one
embodiment, a triple immunization regime employs DNA, then adenovirus as a first
boosting composition, and then MVA as a second boosting composition, optionally
followed by a farther (third) boosting composition or subsequent boosting administration of
one or other or both of the same or different vectors. Another option is DNA then MVA
then adenovirus, optionally followed by subsequent boosting administration of one or other
or both of the same or different vectors.
The antigen to be included in respective priming and boosting compositions
(however many boosting compositions are employed) need not be identical, but should
share epitopes. The antigen may correspond to a complete antigen in a target pathogen or
cell, or a fragment thereof. Peptide epitopes or artificial strings of epitopes may be
employed, more efficiently cutting out unnecessary protein sequence in the antigen and
encoding sequence in the vector or vectors. One or more additional epitopes may be
included, for instance epitopes which are recognized by T helper cells, especially epitopes
recognized in individuals of different HLA types.
Within the recombinant virus, e.g., adenovirus, regulatory sequences for expression
of the encoded antigen will include a promoter. By "promoter" is meant a sequence of
nucleotides from which transportation may be initiated of DNA operably linked
downstream (i.e., in the 3' direction on the sense strand of double-stranded DNA).
"Operably linked" means joined as part of the same nucleic acid molecule, suitably
positioned and oriented for transcription to be initiated from the promoter. DNA operably
linked to a promoter is "under transcriptional initiation regulation" of the promoter. Other
regulatory sequences including terminator fragments, polyadenylation sequences, enhancer
sequences, marker genes, internal ribosome entry site (IRES) and other sequences may be
included as appropriate, in accordance with the knowledge and practice of the ordinary
person skilled in the art: see, for example, Molecular Cloning: a Laboratory Manual, 2nd
edition, Sambrook et al. 1989 Cold Spring Harbor Laboratory Press. Many known
techniques and protocols for manipulation of nucleic acid, for example hi preparation of
nucleic acid constructs, mutagenesis, sequencing, introduction of DNA into cells and gene
expression, and analysis of proteins, are described in detail in Current Protocols in
Molecular Biology, Ausubel et al. eds., John Wiley & Sons, 1994.
Suitable promoters for use in aspects and embodiments of the present invention
include the cytomegalovirus immediate early (CMV IE) promoter, with or without intron A,
and any other promoter that is active in mammalian cells.
Adjuvants suitable for co-administration in accordance with the present invention
should be ones that are potentially safe, well tolerated and effective in people including QS-
21, Detox-PC, MPL-SE, MoGM-CSF, TiterMax-G, CRL-1005, GERBU, TERamide,
PSC97B, Adjumer, PG-026, GSK-1, GcMAF, B-alethine, MPC-026, Adjuvax, CpG ODN,
Betafectin, Alum, and MF59 (see Kim et al., 2000 Vaccine 18:597 and references therein).
Other contemplated adjuvants that may be administered include lectins, growth
factors, cytokines and lymphokines such as alpha-interferon, gamma interferon, platelet
derived growth factor (PDGF), granulocyte-colony sthnulating factor (gCSF), granulocyte
macrophage colony stimulating factor (gMCSF), tumor necrosis factor (TNF), epidermal
growth factor (EOF), IL-1, IL-2, IL-4, IL-6, 3L-8, IL-10, and IL-12 or encoding nucleic
acids therefore.
Administration of the boosting composition is generally weeks or months after
administration of the priming composition, preferably about 2-3 weeks or 4 weeks, or 8
weeks, or 16 weeks, or 20 weeks, or 24 weeks, or 28 weeks, or 32 weeks.
Preferably, administration of single dose composition, boosting composition, or
priming composition is intramuscular immunization.
Intramuscular administration of adenovirus vaccines or plasmid DNA may be
achieved by using a needle to inject a suspension of the virus or plasmid DNA. An
alternative is the use of a needless injection device to administer a virus or plasmid DNA
suspension (using, e.g., Biojector™) or a freeze-dried powder containing the vaccine (e.g.,
in accordance with techniques and products of Powderject), providing for manufacturing
individually prepared doses that do not need cold storage. This would be a great advantage
for a vaccine that is needed in rural areas of Africa.
Adenovirus is a virus with an excellent safety record hi human immunizations. The
generation of recombinant viruses can be accomplished simply, and they can be
manufactured reproducibly in large quantities. Intramuscular administration of
recombinant adenovirus is therefore highly suitable for prophylactic or therapeutic
vaccination of humans against diseases which can be controlled by an immune response.
The individual may haVe a disease or disorder such that delivery of the antigen and
generation of an immune response to the antigen is of benefit or has a therapeutically
beneficial effect.
Most likely, administration will have prophylactic aim to generate an immune
response against a pathogen or disease before infection or development of symptoms.
Diseases and disorders that may be treated or prevented in accordance with the
present invention include those in which an immune response may play a protective or
therapeutic role.
Components to be administered in accordance with the present invention may be
formulated in pharmaceutical compositions. These compositions may comprise a
pharmaceutically acceptable excipient, carrier, buffer, stabilizer or other materials well
known to those skilled in the art. Such materials should be non-toxic and should not
interfere with the efficacy of the active ingredient. The precise nature of the carrier or other
material may depend on the route of administration, e.g., intravenous, cutaneous or
subcutaneous, intramucosal (e.g., gut), intranasal, intramuscular, or intraperitoneal routes.
As noted, administration is preferably intradermal, subcutaneous or intramuscular.
Liquid pharmaceutical compositions generally include a liquid carrier such as water,
petroleum, animal or vegetable oils, mineral oil or synthetic oil. Physiological saline
solution, dextrose or other saccharide solution or glycols such as ethylene glycol, propylene
glycol or polyethylene glycol may be included.
For intravenous, cutaneous or subcutaneous injection, or injection at the site of
affliction, the active ingredient will be in the form of a parenterally acceptable aqueous
solution which is pyrogen-free and has suitable pH, isotonicity and stability. Those of
relevant skill in the art are well able to prepare suitable solutions using, for example,
isotonic vehicles such as Sodium Chloride Injection, Ringer's Injection, Lactated Ringer's
Injection. Preservatives, stabilizers, buffers, antioxidants and/or other additives may be
included, as required.
A slow-release formulation may be employed.
Following production of adenoviral particles and optional formulation of such
particles into compositions, the particles may be administered to an individual, particularly
human or other primate.
Administration may be to another mammal, e.g., rodent such as mouse, rat or
hamster, guinea pig, rabbit, sheep, goat, pig, horse, cow, donkey, dog or cat.
Administration is preferably in a "prophylactically effective amount" or a
"therapeutically effective amount" (as the case may be, although prophylaxis may be
considered therapy), this being sufficient to show benefit to the individual. The actual
amount administered, and rate and time-course of administration, will depend on the nature
and severity of what is being treated. Prescription of treatment, e.g., decisions on dosage
etc., is within the responsibility of general practitioners and other medical doctors, or in a
veterinary context a veterinarian, and typically takes account of the disorder to be treated,
the condition of the individual patient, the site of delivery, the method of administration and
other factors known to practitioners. Examples of the techniques and protocols mentioned
above can be found in Remington's Pharmaceutical Sciences, 16th edition, Osol, A. ed.,
1980.
In one preferred regimen, DNA is administered (preferably intramuscularly) at a
dose of 10 micrograms to 50 milligrams/injection, followed by adenovirus (preferably
intramuscularly) at a dose of 5x10-1x10 particles/injection.
The composition may, if desired, be presented in a kit, pack or dispenser, which
may contain one or more unit dosage forms containing the active ingredient. The kit, for
example, may comprise metal or plastic foil, such as a blister pack. The kit, pack, or
dispenser may be accompanied by instructions for administration.
A composition may be administered alone or in combination with other treatments,
either simultaneously or sequentially dependent upon the condition to be treated.
Delivery to a non-human mammal need not be for a therapeutic purpose, but may be
for use in an experimental context, for instance in investigation of mechanisms of immune
responses to an antigen of interest, e.g., protection against disease or pathogens.
Specific Modifications of Ebola GP Optimize Vaccine Efficacy in Nonhuman Primates
To develop an optimal Ebola vaccine using rAd vectors, we first analyzed mutant
forms of GP in which the transmembrane domain had been removed. Though we have
previously reported that deletion of the mucin domain eliminates cytotoxicity (Yang, Z.-Y.
et al. 2000 Nat Med 6:886-889), this deletion removes nearly 200 amino acids, eliminating
many potential T- and B-cell epitopes. Previous data suggested that the in vitro cytopathic
effects of GP may be mediated at or near the cell surface and require transmembrane
anchoring of the protein (Sullivan, N. J. et al. 2005 J Virol 79:547-553; Takada, A. et al.
2000 Virology 278:20-26; Chan, S. Y. et al. 2000 J Gen Virol 81:2155-2159). An
alternative approach to the elimination of the GP-induced cytopathic effects was therefore
explored by removal of the 26 amino acid putative transmembrane and cytoplasmic
domains.
Diminished immune protection of a mutant GP lacking a transmembrane anchor
domain
GP protein was readily detected in the supernatants of cells transfected with the
transmembrane-deleted vector ATM(Z), confirming its secretion, in contrast to supernatants
from cells transfected with the wild type GP(Z) (Fig. 10A). Furthermore, synthesis of the
two previously defined forms of GP, generated by post-translational processing (Volchkov,
V. E. et al. 1995 Virology 214:421-430; Sanchez, A. et al. 1998 J Virol 72:6442-6447), was
readily detected at comparable levels. Deletion of the transmembrane domain eliminated
GP-induced cytopathicity in transfected 293 cells in contrast to wild type GP (Fig. 10B),
but total ATM expression was equivalent to wild type protein levels (Fig. 10A). To
determine whether the ATM mutant of the Zaire strain could protect against infectious
Ebola challenge, cynomolgus macaques were immunized with rAd vectors encoding NP
and either ATM(Z), or GP(Z). Immunization with GP(Z) + NP protected all animals
vaccinated with either 1011 or 1012 adenoviral particles and challenged with 1000 pfu of the
Zaire strain of Ebola virus 28 days later (Fig. 11 A), hi contrast, survival frequencies
decreased in animals receiving the ATM(Z) vaccine, hi the group vaccinated with 101
adenoviral particles, protective immunity was decreased by 33% and at 10U, by 66%,
indicating a substantial decrease in efficacy in animals vaccinated with ATM + NP vs GP +
NP (p against infection. Analysis of cell-mediated immune responses showed that CD4+ and
CD8+ T-cell responses were present in the majority of animals by 3 weeks postimmunization
(Fig. 1 IB, left and middle panels, respectively) and did not correlate with the
differences in survival: antigen specific cellular responses measured by intracellular
cytokine (TNF-a) secretion were indistinguishable between GP(Z)- and ATM(Z)-
vaccinated animals. Similarly, humoral immune responses measured by anti-Ebola GP
ELISA IgG titers were comparable in all vaccinated animals (Fig. 11B, right panel).
Neutralizing antibody titers were low, and were absent in some surviving animals. These
results suggested that deletion of the GP transmembrane domain reduces vaccine efficacy,
with no readily apparent correlates of protection.
Definition of minimal protective vaccine dose for protection with a rAd vaccine
encoding GP and NP
hi the previous experiment, a log decrease in dose of the GP(Z) + NP vaccine was
protective, in comparison to previous studies using 1012 rAd particles. To establish the
lowest dose of adenoviral vectors that would afford protection against Ebola infection, a
dose-response analysis was performed. Animals were immunized with rAd vectors
encoding GP(Z) and NP at increasing doses from 109 to 1012 particles per animal. Survival
was 100% in all groups receiving a dose of 1010 or greater, whereas challenge infection was
uniformly lethal in the 109 dose group (Fig. 12A). Virus isolation by plaque assay on Vero
cells was negative for all surviving animals. Pre-challenge CD4+ T-cell responses for TNFa
were unremarkable as reported previously for immunized cynomolgus macaques (Fig.
12B). CD8+ T-cell responses were similar across vaccine dose groups, except for the
10 higher responder immunized at 10 rAd particles. Antigen-specific IgG was also generated
in immunized animals, and the levels were equivalent among animals hi the groups that
survived Ebola virus challenge (Fig. 12C, left). However, there was a difference in more
than one log (p=0.004) in IgG levels between survivors immunized at 1010 and fatalities
immunized at 109 rAd particles, suggesting that such levels may correlate with protection
for this immunization regimen. Neutralizing antibody titers against GP did not differ
significantly between survivors and fatalities (Fig. 12C, right). These results indicated that
the threshold for immune protection lies at about ~1010 rAd particles. Therefore,
subsequent experiments were carried out using this dose to increase sensitivity to detect
differences in antigenic strength between various immunogens.
Identification of GP point mutants with diminished in vitro cytotoxicity that confer
effective immune protection
We sought to identify other mutants of GP that do not exhibit cytopathic effects yet
retain native antigenic structures when expressed in vitro. Relatively conserved regions of
GP were identified, and point mutations were systematically introduced. GP proteins
bearing single amino acid changes were screened for decreased induction of cell rounding
but wild type levels of expression and reactivity with conformation-dependent antibodies.
Substitution of aspartic for glutamic acid at position 71 in Ebola GP from the Zaire or
Sudan/Gulu subtypes (E71D(Z), E71D(S/G), respectively) abolished the cell rounding
phenotype in transfected 293 cells but did not alter protein expression or reactivity with
antibodies whose binding properties are sensitive to changes in protein conformation (Fig.
14).
The E71D mutants were evaluated for their ability to induce protective immunity
alone or in combination with NP. When E71D from Zaire and Sudan-Gum were combined
with NP, survival of cynomolgus macaques immunized in these groups was diminished by
33% and 66%, respectively (Fig. 13A). In contrast, complete protection was achieved in
animals immunized with E71D(Z) and E71D(S/G), as it was in animals receiving wild type
GP(Z) plus NP. Ebola GP-specific responses in T-lymphocytes detected by intracellular
staining of TNF-a did not show statistically significant differences in the CD4+ population
between different immunization groups (Fig. 13B, left panel). Similarly, individual
differences in the CD8+ response did not correlate with survival, though there was a trend
toward diminished survival in groups with lower antigen-specific CD8+ cellular responses
(Fig. 13B, middle panel. Antigen-specific ELISA IgG was also stimulated in all
immunized animals (Fig. 13B, right panel). The results of this experiment illustrate that NP
may not be necessary for protective immunity against Ebola infection and that it may
diminish protection when combined with modified GP immunogens at the lower limits of
protective vaccine doses.
Ebola virus outbreaks are associated with high lethality due to the absence of
treatment options or a licensed vaccine. Both DNA priming and rAd vector boosting, as
well as rAd alone can confer protection to lethal challenge in an animal model that closely
parallels human disease (Geisbert, T. W. et al. 2003 Am JPathol 163:2347-2370). The rAd
vector vaccine conferred protection in an accelerated vaccine regimen in nonhuman
primates (Sullivan, N. J. et al. 2003 Nature 424:681-684). Although in vitro cytopathicity
has been observed by over expression of Ebola GP, one of the vaccine components, we
have not seen toxicity in animals vaccinated by vectors expressing Ebola GP. However,
because this hypothetical complication has been raised, we sought to modify GP to
eliminate in vitro cytopathicity yet retain antigenic properties that are necessary for
protective immunity. Here, the efficacies of different forms of GP were evaluated using
doses at the threshold of protection in the accelerated vaccination model. We have
identified a vaccine with decreased in vitro cytopathicity that retained immunogenicity
necessary to protect against Ebola infection.
We find that alternative forms of GP confer differential immune protection.
Deletion of the GP transmembrane domain abolished cytopathic effects in transfected 293
cells, but the corresponding ATM(Z) vaccine was less efficacious than wild type GP(Z) in
protecting nonhuman primates against infection. Though cellular and humoral immune
responses were indistinguishable between groups receiving the different immunogen forms,
the inherent variability in quantitating the responses in outbred macaques may obscure our
ability to identify immune responses restxmsible for higher survival. Alternatively,
ATM(Z) may differ from wild type GP(Z) in antigenic qualities that are not captured by
measurements of total antigen-specific IgG or intracellular cytokine responses stimulated by
a broad peptide pool. For example, the transmembrane-deleted protein is secreted and
likely shows conformational differences from the membrane anchored protein. Subsequent
modifications of the glycoprotein to retain membrane attachment and a more native
envelope structure yielded a mutant, E71D, with reduced in vitro cytopatbicity. Recently, it
has been suggested that this region of GP contributes to viral receptor binding
(Manicassamy, B. et al. 2005 J Virol 79:4793-4805). It is noteworthy that the envelope
glycoprotein cytopathicity of other viruses such as HIV is linked to receptor binding and
fusion (Cao, J. et al. 1996 J Virol 70:1340-1354), raising the possibility that Ebola GP
shares similar properties.
Ongoing outbreaks of both Ebola and Marburg viruses illustrate the importance of
developing a filovirus vaccine for human use. This report shows that protective immunity
against Ebola infection is achieved in nonhuman primates by the generation of antigenspecific
immune responses to a single protein, GP, which has been modified to eliminate invitro
cytopathic effects. The accelerated vaccine strategy has since been repeated using
vescicular stomatitis virus (VSV) vectors (Jones S. M. et al. 2005 Nat Med, published
online June 5, 2005), validating the promise of vaccines for Ebola. However, there are
concerns about the use of VSV as a human vaccine because it is replication-competent and
derives from a virus that is pathogenic in animals, hi contrast, the rAd vector vaccine is
non-replicating, can be manufactured to high yields, and safety data exist for this platform.
Immunity follows a single injection with 1010 rAd particles, a dose that is two orders of
magnitude lower than previously reported for this single modality vaccine. Such doses of
rAd vectors have proven to be well-tolerated and immunogenic for other recombinant genes
in vivo and can be evaluated for the vectors reported here, alone or in DNA prime/rAd
boost combinations. Immunization with 1010 rAd particles of E71D(Z) + E71D(S/G)was
effective against infectious challenge with Ebola Zaire, and protection did not require NP.
Elimination of NP from the vaccine and dose reductions to 1010 rAd particles do not
dimmish protection and simplify the vaccine for future development in human trials.
Example 1
Vector construction and transfections
El/E3-deleted, replication-incompetent Ad5 vectors were generated in PER.C6®
cells (Fallaux, F. J. et al. 1998 Hum Gene Ther 9:1909-1917) using a pBR322-based
adaptor plasmid pAdApt together with cosmid pWE.Ad.Aflin-rITRAE3 essentially as
described elsewhere (Havenga, M. J. et al. 2001 J Virol 75:3335-3342). The adaptor
plasmid contained the left portion of the Ad5 genome (nucleotides 1-454), followed by
transcriptional control elements and the adaptor Ad5 DNA region (nucleotides 3511-6095
in Ad5). Ebola GP encoding genes were cloned into the expression cassette in the adaptor
plasmids under transcriptional control of the human full-length immediate-early CMV
promoter and the SV40 polyadenylation signal. Adenoviruses containing Ebola GP,
GPATM, and point mutations were generated by cotransfection of linearized pAdApt-Ebola
GP plasmids together with the linearized cosmid pWE.Ad.Aflin-rITRAE3 containing the
right portion of the Ad5 genome to PER.C6® cells using Lipofectamine (Invitrogen).
PER.C6® cells were cultured in DMEM supplemented with 10% fetal bovine serum
(GffiCO) and incubated at 37°C under humified atmosphere and 10% COj. Homologous
recombination led to the generation of rAd5-Ebola GP viruses. Adenoviral vectors in crude
lysates were plaque purified using limiting dilutions and agar overlays, and Ad vector
clones were analyzed for presence and expression of the transgene. Positive clones were
amplified for large-scale production using PER.C6® cells in 48 triple-layer 3x175 cm2
flasks. Viruses were purified by standard two-step CsCl gradient ultracentrifugation and
subsequently desalted and formulated by three consecutive dialysis steps into TRIS-C1 pH
8.0 containing 2.5% glycerol. Purified Ad vectors were stored as single use aliquots at -
80°C. Virus particle (vp) titers were determined by anion-exchange high-performance
liquid chromatography based on described procedures (Shabram, P. W. et al. 1997 Hum
Gene Ther 8:453-465). Lnfectivity was assessed by TCID50 using 911 cells. Ebola GP
expression was assessed by infection of A549 cells followed by analysis of culture lysates
on western blot. The identity of the purified vectors was confirmed by PCR. Expression
vectors pi012, pGP and pATM and point mutants contain a CMV enhancer promoter that
have been described previously (Sullivan, NJ. et al. 2000 Nature 408:605-609). The
pATM contains a deletion from amino acid 651 to 676 and was created by digesting with
BspMI/Klenow, and then fusing to TGA. The resulting plasmid also contained four extra
amino acids at the C-terminus (MAAS). 293 human embryonal kidney cells were cultured
in DMEM supplemented with 10% fetal bovine serum (GIBCO). Transfections to measure
protein expression and cell rounding were performed in 293 cells with 2ug DNA per well
of a 6-well plate using calcium phosphate (Invitrogen) according to the manufacturer's
instructions. Protein expression was evaluated by SDS-PAGE followed by Western blot
with a GP-specific antibody kindly provided by A. Sanchez.
Animal study and safety
Cynomolgus macaques (M. fascicularis), 3-5 years old and weighing 2-3 kg,
obtained from Covance, were used for immunization and challenge experiments. The
monkeys, housed singly, were anesthetized with ketamine to obtain blood specimens and to
administer vaccines. In conducting this research, the investigators adhered to the Guide for
the Care and Use of Laboratory Animals, prepared by the Institute of Laboratory Animal
Resources, National Research Council (National Academy Press, Washington, D.C., 1996).
The facilities are fully accredited the Association for Assessment and Accreditation of
Laboratory Animal Care International. They received regular enrichment according to the
Guide for the Care and Use of Laboratory Animals (DHEW No. NIH 86-23). Before Ebola
virus challenge and to the end of each experiment, the animals were maintained in the
Maximum Containment Laboratory (BSL-4) and fed and checked daily.
Macaque immunization and challenge
Cynomolgus macaques were injected intramuscularly with a 1.0 ml equal mixture of
immungens at the doses indicated. Viral challenge was performed by inoculation of
animals in the left or right caudal thigh with 0.5 ml of viral stock that contained a target
dose of ~ 1000 PFU EBOV (Zaire species) at four weeks after the initial immunization. No
adverse effects of the adenovirus vaccination were observed acutely. The Ebola virus used
in this study was originally obtained from a fatally infected human from the former Zaire in
1995 (Jahrling, P. B. et al. 1996 Arch Virol Suppl 11:135-140). Collection of serum and
blood for viral load and ELISA titers was performed as previously described (Sullivan, N.J.
et al. 2000 Nature 408:605-609).
Flow cytoraetry and antibodies
Transfected cells were collected after incubation with PBS (3 mM EDTA) and
incubated with control Ig or rabbit anti-sGP/GP serum (generously provided by Dr. A.
Sanchez) for 30 minutes on ice. The cells were washed twice with ice-cold PBS containing
2.5% fetal bovine serum, incubated with FTTC- or PE-conjugated secondary antibodies
(Jackson ImmunoResearch Laboratories and Sigma, respectively) for 30 minutes on ice,
followed by washing. Analysis was conducted using a Becton Dickinson 4-color Calibur
flow cytometer and FlowJo analysis software (Tree Star, Inc).
ELISA
Nunc-Immuno Maxisorp plates (Nunc, Rochester, NY) were coated with Ebola GP
from 293 cell supernatants and incubated at 4°C until use. All further incubations were
carried out at room temperature. Plates were then washed six times with PBS containing
Tween 20. Test sera were diluted in PBS containing Tween 20 and 1% fetal calf serum and
allowed to react with the Ag-coated wells for 60 minutes. After washing plates six times,
goat anti-human IgG (H+L; Chemicon, Temecula, CA) conjugated to horseradish
peroxidase was used as a detection antibody. Bound IgG was detected by Sigma Fast
o-Phenylenediamine Dihydrochlonde Tablet Sets (Sigma-Aldrich, St. Louis, MO) and the
optical density was determined. A panel of normal sera was run each time the assay was
performed.
Neutralizing antibody analysis
Ebola GP(Z) pseudotyped lentiviral virions were produced as previously described
(Yang, 2004 J Virol 78:5642-5650). Briefly, 293T cells were plated in 10-cm-diameter
tissue culture dishes and transfected the next day by calcium phosphate reagent (Invitrogen)
with pCMVAR8.2, pHR'CMV-Luc and CMV/R Ebola GP(Z) plasmid DNA. Cells were
transfected overnight, washed, and replenished with fresh medium. Forty-eight hours later,
supernatants containing pseudotyped virus were harvested, filtered through a 0.45-um-poresize
syringe filter, and stored in aliquots at -80°C. Neutralization assays were performed on
HUVECs (Cambrex CC-2517) plated in a 24 well plate 1 day prior to infection. Virus
stocks were incubated at 37°C for 1 hour in the presence of serum from immunized
cynomolgus macaques. The culture media was removed from the cells and replaced with
the virus/serum media in the presence of polybrene (Sigma-Aldrich, 107689) at a final
concentration of 5ug/mL. 72 hours post infection cells were lysed and assayed by
Luciferase Assay System (Promega, E1501/E1531). Luciferase activity was determined
using a Veritas Microplate Luminometer from Turner Biosystems.
Intracellular cytokine analysis
Peripheral blood mononuclear cells (PBMC) were isolated from cynomolgus
macaque whole blood samples by separation over Ficoll. Approximately 1 x 106 cells were
stimulated in 200 ul RPMI medium (GffiCO) for 6 hours at 37°C with anti-CD28 and -
CD49d antibodies, brefeldin A, and either DMSO or a pool of 15-mer peptides spanning
the Ebola GP Zaire (Mayinga strain) open reading frame. The peptides were 15-mers
overlapping by 11 spanning the entire Ebola glycoprotein at a final concentration of 2
jag/ml. Cells were fixed and permeablized with FACS Lyse (Becton Dickinson)
supplemented with Tween 20, and stained with a mixture of antibodies against lineage
markers (CD3-PE, CD4-PerCP, CD8-FITC) and either TNF-APC. Samples were run on a
FACS Calibur or FACS Aria and analyzed using the software FlowJo. Positive gating for
lymphocytes using forward vs. side scatter was followed by CD3+/CD8" and CD3+/CD4"
gating, and specific populations were further defined by anti-CD4 and anti-CD8 positivity,
respectively. Cytokine positive cells were defined as a percentage within these individual
lymphocyte subsets and at least 200,000 events were analyzed for each sample.
***
While the present invention has been described in some detail for purposes of clarity
and understanding, one skilled in the art will appreciate that various changes in form and
detail can be made without departing from the true scope of the invention. All figures,
tables, and appendices, as well as patents, applications, and publications, referred to above,
are hereby incorporated by reference.




1. A nucleic acid molecule comprising a polynucleotide encoding a modified
filovirus glycoprotein (GP) having at least one ammo acid change located in a relatively
conserved region of said GP that decreases in vitro cytotoxicity and retains immunogenicity
when compared to in vitro cytotoxicity and immunogenicity of a wild type filovirus GP.
2. The nucleic acid molecule of Claim 1, wherein said amino acid change is
positioned in the N-terminal domain, excluding the conserved cysteine residues, and is
located at ammo acid position 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,
66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89,
90, 91, 92, 93, 94, 95, 96,97, 98, 99,100,101,102,103,104,105,106, 107,108, 109,110,
111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128,
129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146,
147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164,
165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182,
183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200,
201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218,
219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236,
237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254,
255, 256, 257, 258, 259, 260, 261, 262, 263, 264, 265, 266, 267, 268, 269, 270, 271, 272,
273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290,
291, 292, 293, 294, 295, 296, 297, 298, 299 or 300 in Ebola Zaire GP in an exemplary
manner or corresponding thereto in other strains of said GP.
3. The nucleic acid molecule of Claim 2, wherein said amino acid change is
located at amino acid position 71 or 102 in Ebola Zaire GP in an exemplary manner or
corresponding thereto in other strains of said GP.
4. The nucleic acid molecule of Claim 3, whereinsaid amino acid change is
E71D or G102A in Ebola Zaire GP in an exemplary manner or corresponding thereto in
other strains of said GP.
5. The nucleic acid molecule of Claim 4, wherein said modified filovirus GP is
encoded by the insert of SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQ
ID NO:6, SEQ ID NO:7 or SEQ ID NO:8, or sequence having at least 95% identity thereto.
6. The nucleic acid molecule of Claim 5, wherein said polynucleotide encoding
said modified filovirus GP has a sequence taken from the insert of SEQ ID NO:1, SEQ ID
NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQ ID N0:6, SEQ ID NO:7, or SEQ ID NO:8, or
sequence having at least 95% identity thereto.
7. A modified filovirus GP encoded by the nucleic acid molecule of any of
Claims 1-6.
8. A plasmid DNA comprising the nucleic acid molecule if any of Claims 1-6.
9. A recombinant virus comprising the nucleic acid molecule if any of Claims
1-6.
10. An adenovirus comprising the nucleic acid molecule if any of Claims 1-6.
11. A pharmaceutical composition comprising the nucleic acid molecule of any
of Claims 1-6 or the modified filovirus GP of Claim 7 in a therapeutically effective dose.
12. A vaccine composition comprising the nucleic acid molecule of any of
Claims 1-6 or the modified vfilovirus GP of Claim 7 in a prophylactically effective dose.
13. The composition of Claim 11 or 12 further comprising an adjuvant.
14. An antibody that is specifically reactive with the modified filovirus GP of
Claim 7.
15. A method of boosting an immune response to an antigen in a primate, the
method comprising provision in the primate of the modified filovirus GP of Claim 7 or the
recombinant virus of Claim 9, whereby an immune response to the antigen previously
primed in the primate is boosted.
16. A method of inducing an immune response to an antigen in a primate, the
method comprising provision in the primate of the nucleic acid molecule of any of Claims
1-6 or the modified filovirus GP of Claim 7, whereby an immune response to the antigen in
the primate is induced.
17. A method of inducing an immune response to an antigen in a primate, the
method comprising provision in the primate of a pruning composition comprising the
nucleic acid molecule of any of Claims 1-6 or the modified filovirus GP of Claim 7 and
then provision in the primate of a boosting composition comprising the antigen or a
recombinant virus encoding the antigen.
18. The method of any of Claims 15-17, wherein the primate is a human.
19. A method of making the nucleic acid molecule of any of Claims 1-6
comprising preparing an adapter plasmid and achieving recombination with a virus genome
to produce a recombinant virus composed of the nucleic acid molecule of any of Claims 1-
6.
20. A nucleic acid molecule having SEQ ID NO:1, SEQ ID NO:2, SEQ ID
NO:3, SEQ ID NO:4, SEQ ID NO:5, SEQ ID N0:6, SEQ ID NO:7, or SEQ ID NO:8, or
insert thereof encoding modified or wild type filovirus GP.

Documents:

2674-delnp-2007-Abstract-(18-03-2014).pdf

2674-delnp-2007-abstract.pdf

2674-delnp-2007-Claims-(04-07-2013).pdf

2674-delnp-2007-Claims-(18-03-2014).pdf

2674-delnp-2007-claims.pdf

2674-delnp-2007-correspondece-others.pdf

2674-delnp-2007-Correspondence Others-(04-07-2013).pdf

2674-delnp-2007-Correspondence Others-(18-03-2014).pdf

2674-delnp-2007-Correspondence-others (04-10-2007).pdf

2674-delnp-2007-Correspondence-others (10-07-2008).pdf

2674-delnp-2007-Correspondence-others (19-06-2007).pdf

2674-delnp-2007-Correspondence-Others-(01-02-2013).pdf

2674-delnp-2007-Correspondence-Others-(03-03-2014).pdf

2674-delnp-2007-description (complete).pdf

2674-delnp-2007-drawings.pdf

2674-delnp-2007-form-1.pdf

2674-delnp-2007-Form-18 (10-07-2008).pdf

2674-delnp-2007-Form-2-(18-03-2014).pdf

2674-delnp-2007-form-2.pdf

2674-delnp-2007-Form-3 (04-10-2007).pdf

2674-delnp-2007-Form-3-(01-02-2013).pdf

2674-delnp-2007-Form-3-(04-07-2013).pdf

2674-delnp-2007-form-3.pdf

2674-delnp-2007-form-5.pdf

2674-delnp-2007-GPA (19-06-2007).pdf

2674-delnp-2007-GPA-(03-03-2014).pdf

2674-delnp-2007-pct-101.pdf

2674-delnp-2007-pct-210.pdf

2674-delnp-2007-pct-237.pdf

2674-delnp-2007-pct-304.pdf

2674-delnp-2007-pct-373.pdf


Patent Number 259912
Indian Patent Application Number 2674/DELNP/2007
PG Journal Number 14/2014
Publication Date 04-Apr-2014
Grant Date 29-Mar-2014
Date of Filing 10-Apr-2007
Name of Patentee THE SECRETARY, DEPARTMENT OF HEALTH AND HUMAN SERVICES
Applicant Address NATIONAL INSTITUTE OF HEALTH, OFFICE OF TECHNOLOGY, 6011 EXECUTIVE BLVD.,SUITE 325, ROCKVILLE, MD MARYLAND 20852-3804, USA
Inventors:
# Inventor's Name Inventor's Address
1 SULLIVAN, NANCY 4217 COLCHESTER DRIVE, KENSINGTON, MD 20895, USA
2 CHAKRABARTI, BIMAL 361 WEST SIDE DRIVE, #102, GAITHERSBURG, MD 20878, USA
3 YANG,ZHI-YONG 10004 PENFOLD COURT, POTOMAC, MD 20854, USA
4 PAU,MARIA,GRAZIA BARGELAAN 80, NL-2333 CW LEIDEN (NL)
5 GOUDSMIT,JAAP KONINGINNEWEG 4, NL-1075 CX AMSTERDAM (NL)
6 NABEL, GARY,J 2520 30TH STREET NW, WASHINGTON, DC 20008, USA
PCT International Classification Number C07K 14/08
PCT International Application Number PCT/US2005/034798
PCT International Filing date 2005-09-27
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/701,694 2005-07-22 U.S.A.
2 60/677,606 2005-05-03 U.S.A.
3 60/613,883 2004-09-27 U.S.A.
4 60/679,767 2005-05-10 U.S.A.
5 60/715,874 2005-09-09 U.S.A.