Monoclonal Antibodies for Ebola and Marburg Viruses

Abstract

Described herein are a number of Ebola and Marburg monoclonal antibodies.

Description

PRIOR APPLICATION INFORMATION

[0001] The instant application is a continuation application of U.S. patent application Ser. No. 14/979,834 filed Dec. 28, 2015, itself a continuation application of U.S. patent application Ser. No. 13/940,712, filed Jul. 12, 2013, which was a divisional application of U.S. Ser. No. 12/864,584, filed Oct. 26, 2010, which was a 371 of PCT Application CA2009/000070, filed Jan. 27, 2009, which claims the benefit of US Provisional Patent Application 61/025,491, filed Feb. 1, 2008.

BACKGROUND OF THE INVENTION

[0002] Ebola and Marburg viruses are highly pathogenic and virulent viruses causing rapidly fatal hemorrhagic fever in humans.

SUMMARY OF THE INVENTION

[0003] According to a first aspect of the invention, there is provided a monoclonal antibody comprising an amino acid sequence deduced from 1 H3-light (SEQ ID No. 2); 2G4-light (SEQ ID No. 4); 4G7-light (SEQ ID No. 6): 5D2-light (SEQ ID No. 8); 5E6-light (SEQ ID No. 10); 7C9-light (SEQ ID No. 12): 7G4-light (SEQ ID No. 14), 10C8-light(SEQ ID No. 16), 1H3-heavy (SEQ ID No. 1): 2G4-heavy (SEQ ID No. 3); 4G7-heavy (SEQ ID No. 5); 5D2-heavy (SEQ ID No. 7), 5E6-heavy (SEQ ID No. 9), 7C9-heavy (SEQ ID No. 11), 7G4 heavy (SEQ ID No. 13) and 10C8-heavy (SEQ ID No. 15).

[0004] According to a second aspect of the invention, there is provided a method of preparing a chimeric antibody comprising;

[0005] providing an expression vector comprising a nucleic acid molecule encoding a constant region domain of a human light chain or heavy chain genetically linked to a nucleic acid encoding a light chain variable region selected from the group consisting of 1H3-light (SEQ ID No. 2): 2G4-light (SEQ ID No. 4); 4G7-light (SEQ ID No. 6); 5D2-light (SEQ ID No. 8); 5E6-light (SEQ ID No. 10); 7C9-light (SEQ ID No. 12); 7G4-light (SEQ ID No. 14) and 10C8-light(SEQ ID No. 16) or a heavy chain variable region selected from the group consisting of 1H3-heavy (SEQ ID No. 1): 2G4-heavy (SEQ ID No. 3); 4G7-heavy (SEQ ID No. 5); 5D2-heavy (SEQ ID No. 7), 5E6-heavy (SEQ ID No. 9), 7C9-heavy (SEQ ID No. 11) 7G4-heavy (SEQ ID No. 13) and 10C8-heavy (SEQ ID No. 15):

[0006] expressing the expression vector in a suitable host; and

[0007] preparing a recombinant antibodies comprising:

[0008] providing a nucleotide sequence selected from the group consisting of 1H3-light (SEQ ID No. 2); 2G4-light (SEQ ID No. 4); 4G7-light (SEQ ID No. 6); 5D2-light (SEQ ID No. 8); 5E6-light (SEQ ID No. 10); 7C9-light (SEQ ID No. 12); 7G4-light (SEQ ID No. 14), 10C8-light(SEQ ID No. 16), 1H3-heavy (SEQ ID No. 1); 2G4-heavy (SEQ ID No. 3); 4G7-heavy (SEQ ID No. 5); 5D2-heavy (SEQ ID No. 7), 5E6-heavy (SEQ ID No. 9), 7C9-heavy (SEQ ID No. 11), 7G4-heavy (SEQ ID No. 3) and 10C8-heavy (SEQ ID No. 15);

[0009] modifying said nucleic acid sequence such that at least one but fewer than about 30 of the amino acid residues encoded by said nucleic acid sequence has been changed or deleted without disrupting antigen binding of said peptide; and

[0010] expressing and recovering said modified nucleotide sequence.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1. Kaplan-Meier survival curve of mice infected with MA-ZEBOV and treated with MAbs 1 day after infection. Survival curve of MS-Ebola virus-infected mice treated with 100 .mu.g of MAbs. Mice were intraperitoneally treated with 100 .mu.g of each MAb on day 1. Control mice were given equal volumes of PBS.

[0012] FIG. 2. Weight changes of GPA-Ebola infected guinea pigs treated with MAbs. Weight changes of virus-infected guinea pigs treated with cocktail of MAbs. Guinea pigs were intraperitoneally treated with either 5D2, 5E6, 7C9, 7G4 or 10C8 (3 mg/treatment) on day 1 and 4G7+1H3+2G4[(2 mg+1 mg+1 mg)/treatment] on day 2. Control guinea pig were given equal volume of PBS. The results are shown as the means and standard deviations of 6 guinea pigs.

[0013] FIG. 3. Weight changes of GPA-Ebola infected guinea pigs treated with MAbs. Weight changes of virus-infected guinea pigs treated with cocktail of MAbs. Guinea pigs were intraperitoneally treated with either 5D2, 5E6, 7C9, 7G4 or 10C8 (3 mg/treatment) on day 1 and 4G7+1H3+2G4 [(2 mg+1 mg+1 mg)/treatment] on day 2. Control guinea pig were given equal volume of PBS. The results are shown as the group weight of 6 guinea pigs.

[0014] FIG. 4. Immunoprecipitation, 293T cells were transfected with pCAGGS-ZEbovGP1,2 by using Fugene 6, After 48 hrs, cells were collected and washed 2.times. with cold PBS before being lysed with 2.times. RIPA buffer. After clarifying the cell lysate, 100 .mu.g protein was added to each MoNs (5 .mu.g) coupled protein A+G beads. The IP samples were run 10% SDS-PAGE and transferred to Hybond-P membrane. The blot was probed with mouse ant-EBOV-GP1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications mentioned hereunder are incorporated herein by reference.

Definitions

[0016] As used herein, "neutralizing antibody" refers to an antibody, for example, a monoclonal antibody, capable of disrupting a formed viral particle or inhibiting formation of a viral particle or prevention of binding to or infection of mammalian cells by a viral particle.

[0017] As used herein, "diagnostic antibody" or "detection antibody" or "detecting antibody" refers to an antibody, for example, a monoclonal antibody, capable of detecting the presence of an antigenic target within a sample. As will be appreciated by one of skill in the art, such diagnostic antibodies preferably have high specificity for their antigenic target.

[0018] As used herein, "humanized antibodies" refer to antibodies with reduced immunogenicity in humans.

[0019] As used herein, "chimeric antibodies" refer to antibodies with reduced immunogenicity in humans built by genetically linking a non-human Variable region to human constant domains.

[0020] Described herein are a number of Ebola and Marburg monoclonal antibodies. Specifically, antigens were developed using a live replicating vector vesicular stomatitis virus described in PCT Application PCT/CA03/001125.

[0021] The VSV based vaccine delivery system was used to develop monoclonal antibodies in mice.

[0022] Specifically, described herein are monoclonal antibodies 1H3, 2G4, 4G7, 5D2, 5E6, 7C9, 7G4 and 10C8. As discussed below, 1H3 comprises 1H3-heavy chain (SEQ ID No. 1) and 1H3-light chain (SEQ ID No. 2); 2G4 comprises 2G4-heavy chain (SEQ ID No. 3) and 2G4-light chain (SEQ ID No. 4); 4G7 comprises 4G7-heavy chain (SEQ ID No. 5) and 4G7-light chain (SEQ ID No. 6); 5D2 comprises 5D2-heavy chain (SEQ ID No. 7) and 5D2-light chain (SEQ ID No. 8); 5E6 comprises 5E6-heavy chain (SEQ ID No. 9) and 5E6-light chain (SEQ ID No. 10); 7C9 comprises 7C9-heavy chain (SEQ ID No. 11) and 7C9-light chain (SEQ ID No. 12); 7G4 comprises 7G4-heavy chain (SEQ ID No. 13) and 7G4-light chain (SEQ ID No. 14); and 10C8 comprises 10C8-light chain (SEQ ID No. 16) and 10C8-heavy chain (SEQ ID No. 15).

[0023] These antibodies also appear to have high affinity and avidity to Ebola glycoproteins, which means that they could be used as highly sensitive diagnostic tools.

[0024] For example, as shown in FIG. 1, mice infected with MA-ZEBOV and subsequently treated with the monoclonal antibodies described above showed increased survival compared to mice treated with PBS. Results are summarized in Tables 1 and 2.

[0025] FIGS. 2 and 3 show weight changes in guinea pigs treated with the monoclonal antibodies or mixtures thereof post infection. As can be seen, guinea pigs treated with the monoclonal antibodies showed consistent weight while those treated with PBS showed significant weight loss. Results are summarized in Table 3.

[0026] The nucleotide sequences of the heavy and light chains of 1H3, 2G4, 4G7, 5D2, 5E6, 7C9, 7G4 and 10C8 follow. As will be appreciated by one of skill in the art, the amino acid sequences of these antibodies can easily be deduced from the nucleotide sequences. Accordingly, in some embodiments, the invention is directed to amino acid sequences deduced from 1H3-light (SEQ ID. No. 2); 2G4-light (SEQ ID No. 4); 4G7-light (SEQ ID No. 6); 5D2-light (SEQ ID No. 8); 5E6-light (SEQ ID No. 10); 7C9-light (SEQ ID No. 12); 7G4-light (SEQ ID No. 14), 10C8-light(SEQ ID No. 16), 1H3-heavy (SEQ ID No. 1); 2G4-heavy (SEQ ID No. 4G7-heavy (SEQ ID No. 5); 5D2-heavy (SEQ ID No. 7), 5E6-heavy (SEQ ID No. 9), 7C9-heavy (SEQ ID No. 11), 7G4-heavy (SEQ ID No. 13) and 10C8-heavy (SEQ ID No. 15).

TABLE-US-00001 mAb 1H3 heavy chain sequence: 373 bp (SEQ ID No. 1) TGGGGCAGAGCTTGTGAAGCCAGGGGCCTCAGTCAAGTTGTCCTGCACAG CTTCTGGCTTCAACATTAAAGACACCTATATACATTGGGTGAAACAGGGC GCCTGAACAGGGCCTGGAGTGGATTGGAAGGATTGATCCTGCGAATGGTA ATACTAAATATGACCCGAAGTTCCAGGGCAAGGCCACTATCACAGCAGAC ACATCCTCCAATACAGCCTACCTGCAGCTCAGCGGCCTGACATCTGAGGA CACTGCCGTCTATTACTGTGCTAGGGAGTCGAGGATATCTACTATGCTTA CGACGGGGTACTTTGACTACTGGGGCCAAGGCACCACTCTCACAGTCTCC TCAGCCAAAACAACAGCCCCATCG mAb 1H3 light chain sequence: 303 bp (SEQ ID No.2) GCAATCATGTCTGCATCTCCAGGGGAGAAGGTCACCATGACCTGCAGTGC CAGCTCAAGTGTAAGTTACATGTACTGGTACCAGCAGAAGCCAGGATCCT CCCCCAGACTCCTGATTTATGACACATCCAACCTGGCTTCTGGAGTCCCT GTTCGCTTCAGTGGCAGTGGGTCTGGGACCTCTTACTCTCTCACAATCAG CCGAATGGAGGCTGAAGATGCTGCCACTTATTACTGCCAGCAGTGGAGTA GTTACCCGTACACGTTCGGAGGGGGGACCAAGCTGGAAATAAAACGGGCT GAT mAb 2G4 heavy chain sequence: 364 bp (SEQ ID No. 3) TGGAGGAGGCTTGATGCAACCTGGAGGATCCATGAAACTCTCCTGTGTTG CCTCAGGATTCACTTTCAGTAACTACTGGATGAACTGGGTCCGCCAGTCT CCAGAGAAGGGGCTTGAGTGGGTTGCTGAAATTAGATTGAAATCTAATAA TTATGCAACACATTATGCGGAGTCTGTGAAAGGGAGGTTCACCATTTCAA GAGATGATTCCAAAAGGAGTGTCTACCTGCAAATGAATACCTTAAGAGCT GAAGACACTGGCATTTATTACTGTACCCGGGGGAATGGTAACTACAGGGC TATGGACTACTGGGGTCAAGGAACCTCAGTCACCGTCTCCTCAGCCAAAA CAACACCCCCATCA mAb 2G4 light chain sequence: 306 bp (SEQ ID No. 4) GCCTCCCTATCTGTATCTGTGGGAGAAACTGTCTCCATCACATGTCGAGC AAGTGAGAATATTTACAGTAGTTTAGCATGGTATCAGCAGAAACAGGGAA AATCTCCTCAGCTCCTGGTCTATTCTGCAACAATCTTAGCAGATGGTGTG CCATCAAGGTTCAGTGGCAGTGGATCAGGCACTCAGTATTCCCTCAAGAT CAACAGCCTGCAGTCTGAAGATTTTGGOACTTATTACTGTCAACATTTTT GGGGTACTCCGTACACGTTCGGAGGGGGGACCAAGCTGGAAATAAAACGG GCTGAT mAb 4G7 heavy chain sequence: 358 bp (SEQ ID No. 5) TGGACCTGAGCTGGAGATGCCTGGCGCTTCAGTGAAGATATCCTGCAAGG CTTCTGGTTCCTCATTCACTGGCTTCAGTATGAACTGGGTGAAGCAGAGC AATGGAAAGAGCCTTGAGTGGATTGGAAATATTGATACTTATTATGGTGG TACTACCTACAACCAGAAATTCAAGGGCAAGGCCACATTGACTGTGGACA AATCCTCCAGCACAGCCTACATGCAGCTCAAGAGCCTGACATCTGAGGAC TCTGCAGTCTATTACTGTGCAAGATCGGCCTACTACGGTAGTACTTTTGC TTACTGGGGCCAAGGGACTCTGGTCACTSTCTCTGCAGCCAAAACAACAG CCCCATCG mAb 4G7 light chain sequence: 306 bp (SEQ ID No. 6) GCCTCCCTATCTGCATCTGTGGGAGAAACTGTCACCATCACATGTCGAGC AAGTGAGAATATTTACAGTTATTTAGCATGGTATCAGCAGAAACAGGGAA AATCTCCTCAGCTCCTGGTCTATAATGCCAAAACCTTAATAGAGGGTGTG CCATCAAGGTTCAGTGGCAGTGGATCAGGCACACAGTTTTCTCTGAAGAT CAACAGCCTGCAGCCTGAAGATTTTGGGAGTTATTTCTGTCAACATCATT TTGGTACTCCATTCACATTCGGCTCGGGGACAGAGTTGGAAATAAAACGG GCTGAT mAb 5D2 heavy chain sequence: 340 bp (SEQ ID No. 7) GGGACCTGGCCTGGTGAGACCTTCTCAGTCTCTGTCCCTCACCTGCACTG TCACTGGCTACTCAATCACCAGTGATTATGCCTGGAACTGGATCCGGCAG TTTCCAGGAAACAAACTGGAGTGGCTGGGCTATATAACCAACACTGGTAG CACTGGCTTCAACCCATCTCTCAAAAGTCGAATCTCTATCACTCGAGACA CATCCAAGAACCAGTTCTTCCTGCAGTTGATTTCTGTGACTACTGAGGAC ACAGCCACATATCACTGTGCAAGGGGCCTTGCYTACTGGGGCCAAGGGAC TCTGGTCACTGTCTCTGCAGCCAAAACAACAGCCCCATCG mAb 5D2 light chain sequence: 321 bp (SEQ ID No. 8) CTCACTTTGTCGGTTACCATTGGACAACCAGCCTCCATCTCTTGCAAGTC AAGTCAGAGCCTCTTAGATAGTGATGGAAAGACATATCTGAATTGGTTGT TACAGAGGCCAGGCCAGTCTCCAAAGCGCCTAATCTATCTGGTGTCTAAA CTGGACTCTGGAGTCACTGACAGGTTCACTGGCAGTGGATCAGGGACAGA TTTCACACTGAAAATCAGCAGAGTGGAGGCTGAGGATTIGGGAGTTTATT ATTGTTGGCAAGGTACACACTCTCCATTCACGTTCGGCTCGGGGACAAAG TTGGAAATAAAACGGGCTGAT mAb 5E6 heavy chain sequence: 370 bp (SEQ ID No. 9) TGGGGGAGGCTTAGTGAAGCCTGGAGGGTCCCTGAAACTCTCCTGTGCAG CCTCTGGATCCGCTTTCAGTAGATATGACATGTCTTGGGTTCGCCAGACT CCGGAGAAGAGGCTGGAGTGGGTCGCATACATTAGTCGTGGTGGTGGTTT CATCTACTATCCAGACACTGTGAAGGGCCGATTCACCATCTCCAGAGACA ATGCCAAGAACACCCTGTACCTGCAAATGAGCAGTCTGAAGTCTGACGAC ACAGCCATGTATTACTGTGCAAGACACGTTTACTACGGTAGTAGCCCGCT CTATGCTATGGACTACTGGGGTCAAGGAACCTCAGTCACCGTCTCCTCAG CCAAAACAACAGCCCCATCG mAb 5E6 light chain sequence: 324 bp (SEQ ID No. 10) TCAGCCTCTTTGTCCCTGGGAGCCTCAGCAAAACTCACGTGCACCTTGAG TAGTCAGCACAGTACGTTCACCATTGAATGGTATCAGCAACAGCCACTCA AGCCTCCTAAGTATGTGATGGAGCTTAAGAAAGATGGAAGCCACAGTACA GGTGATGGGATTCCTGATCGCTTCTCTGGATCCAGCTGGTGCTGATCGCT ACCTTAGCATTTCCAACATCCAGCCTGAAGATGAAGCAATATACATCTGT GGTGTGGGTGATACAATTAATGAACAATTTGTGTATGTTTTCGGCGGTGG AACCAAGGTCACTGTCCTAGGT mAb 7C9 heavy chain sequence: 358 bp (SEQ ID No. 11) TGGGGCAGAGCTTGTGAAGCCAGGGGCCTCAGTCAAGTTGTCCTGCACAG CTTCTGGCTTCAACATTAAAGACACCTATATGCACTGGGTGAAGGAGAGG CCTGACAAGGGCCTGGAGTGGATTGGAAGGATTGATCCAGCGAATGGTAA TACTAAATGTGACTCGAGGTTTCAGGGCAAGGCCACTATAACAGCAGACA CATCCTCCAACACAGCCTACCTGCAGCTCAGCAGCCTGACATCTGAGGAC ACTGCCGTCTATTACTGTGCTAGAAGGATCTACTTTGGTAAGGGCTTTGA CTTTTGGGGCCAAGGCACCACTCTCACAGTCTCCTCAGCCAAAACAACAG CCCCATCG mAb 7C9 light chain sequence: 324 bp (SEQ ID No. 12) TCCTCCCTGAGTGTGTCAGCAGGAGAGAAGGTCACTATGAGCTGCAAGTC CAGTCAGAGTCTGTTTAACAGTGGAGATCAAAAGAACTACTTGGCCTGGT ACCAGCAGAAACCAGGGCAGCCTCCTAAACTGTTGATCTACGGGGCATCC ACTAGGGAATCTGGGGTCCCTGATCGCTTCACAGGCAGTGGATCTGGAAC CGATTTCACTCTTACCATCAGCAGTGTGCAGGCTGAAGACCTGGCAGTTT ATTACTGTCAGAATGATCAATTTTATCCTCCCACGTTCGGTGATGGGACC AAGCTGGACCTGAAACGGGCTGAT mAb 7G4 heavy chain sequence: 367 bp (SEQ ID No. 13) TGGAGGGGGCTTGGTACAGCCTGGGGGTTCTCTGAGACTCTCCTGTGCAA CTTCTGGCTTCACCTTTACTGATCACTACATGGGCTGGGTCCGCCAGCCT CCAGGAAAGGCACTTGAGTGGTTGGCTTTTGTTAGATACAAAGCTAAGGG TTACACAACAGAGTACACTGCATCTGTGAAGGGTCGGTTCACCATCTCCA GAGATAATTCCCAAAGCATCCTCTATCTTCAAATGAACACCCTGAGAACT GAGGACAGTGCCACTTATTACTGTGCAAGAGATAGAGGGGGTTACGTGGG AGCTATGGACTACTGGGGTCAAGGAACCTCAGTCACCGTCTCCTCAGCCA AAACGACACCCCCATCT mAb 7G4 light chain sequence 321 bp (SEQ ID No. 14) CTCTCCCTGCCTGTCAGTCTTGGAGATCAAGCCTCCATCTCTTGCAGATC TAGTCAGAGCCTTGTACACAGGAATGGAAACACCTATTTCCATTGGTACC TGCAGAAGCCAGGCCAGTCTCGACTCCTGATCTACAAAGTTTCCAACCGA TTTTCTGGGGTCCCAGACAGGTTCAGTGGCAGTGGATCAGGGACAGATTT CACACTCAAGATCAGCAGAGTGGAGGCTGAGGATCTGGGAGTTTATTTCT GCTCTCAAAGTACACATGTTCCGTACACTTTCGGAGGGGGGACCAAGCTG GAAATAAAACGGGCTGAT mAb 10C8 heavy chain sequence: 352 bp (SEQ ID No. 15) TGGGGCAGAGCTTGTGAGGTCAGGGGCCTCAGTCAAGTTGTCCTGCACAT CTTCTGGCTTCAACATTAAAGACTACTTTCTACACTGGGTGAAACAGAGG CCTGAACAGGGCCTGGAGTGGATTGGATGGATTGATCCTGAGAATGGTGA TACTGAATATGCCCCGAAGTTCCAGGACAAGGCCACTATGACTGCAGACA CATCCTCCAACACAGCCTACCTGCACCTCAGCAGCCTGACATCTGAGGAC ACTGGCGTCTATTACTGTAATGCAGATGGTAACTACGGGAAGAACTACTG

GGGCCAAGGCACCACTCTCACCGTCTCCTCAGCCAAAACAACAGCCCCAT CG mAb 10C8 light chain sequence: 324 bp (SEQ ID No. 16) CTCTCCCTGCCTGTCAGTCTTGGAGATCAAGCCTCCATCTCTTGCAGATC TAGTCAGAGCCTTGTACACAGTAATGGAAACACCTTTTTACATTGGTACC TGCAGAAGCCAGGCCAGTCTCCAAAGCTCCTGATCTACAGAGTTTCCAAC CGATTTTCTGGGGTCCCAGACAGGTTCAGTGGCAGTGGATCAGGGACAGA TTTCACACTCAAGATCAGCAGAGTGGAGGCTGAGGATCTGGGAGTTTATT TCTGCTCTCAAAGTACACATGTTCCTCCGTACACGTTCGGAGGGGGGACC AAGCTGGAAATAAAACGGGCTGAT

[0027] In another embodiment of the invention, one or more of the nucleic acid sequences described above encoding the antibody are subjected to humanization techniques or converted into chimeric human molecules for generating a variant antibody which has reduced immunogenicity in humans. Humanization techniques are well known in the art--see for example U.S. Pat. No. 6,309,636 and U.S. Pat. No. 6,407,213 which arm incorporated herein by reference specifically for their disclosure on humanization techniques. Chimerics are also well known, see for example U.S. Pat. No. 6,461,824, U.S. Pat. No. 6,204,023, U.S. Pat. No. 6,020,153 and U.S. Pat. No. 6,120,767 which are similarly incorporated herein by reference.

[0028] In one embodiment of the invention, chimeric antibodies are prepared by preparing an expression vector which comprises a nucleic acid encoding a constant region domain of a human light or heavy chain genetically linked to a nucleic acid encoding a light chain variable region selected from the group consisting of 1H3-light (SEQ ID No. 2); 2G4-light (SEQ ID No. 4); 4G7-light (SEQ ID No. 6); 5D2-light (SEQ ID No. 8): 5E6-light (SEQ ID No. 10); 7C9-light (SEQ ID No. 12); 7G4-light (SEQ ID No. 14) and 10C8-light(SEQ ID No. 16) or a heavy chain variable region selected from the group consisting of 1H3-heavy (SEQ ID No. 1); 2G4-heavy (SEQ ID No. 3); 4G7-heavy (SEQ ID No. 5); 5D2-heavy (SEQ ID No. 7). 5E6-heavy (SEQ ID No. 9), 7C9-heavy (SEQ ID No. 11), 7G4-heavy (SEQ ID No. 13) and 10G8-heavy (SEQ ID No. 15). It is of note that all of these sequences are described above.

[0029] In another embodiment of the invention, there are provided recombinant antibodies comprising at least one modified variable region, said region selected from the group consisting of 1H3-light (SEQ ID No. 2); 2G4-light (SEQ ID No. 4); 4G7-light (SEQ ID No. 6); 5D2-light (SEQ ID No. 8); 5E6-light (SEQ ID No. 10); 7C9-light (SEQ ID No. 12); 7G4-light (SEQ ID No. 14), 10C8-light(SEQ ID No. 16), 1H3-heavy (SEQ ID No. 1); 2G4-heavy (SEQ ID No. 3); 4G7-heavy (SEQ ID No. 5); 5D2-heavy (SEQ ID No. 7), 5E6-heavy (SEQ ID No. 9), 7C9-heavy (SEQ ID No. 11), 7G4-heavy (SEQ ID No. 13) and 10C8-heavy (SEQ ID No. 1), in which at least one but fewer than about 30 of the amino acid residues of said variable region has been changed or deleted without disrupting antigen binding. It is of note that all of these sequences are described above.

[0030] In yet other embodiments, immunoreactive fragments of any of the above-described monoclonal antibodies, chimeric antibodies or humanized antibodies are prepared using means known in the art, for example, by preparing nested deletions using enzymatic degradation or convenient restriction enzymes.

[0031] It is of note that in all embodiments describing preparation of humanized antibodies, chimeric antibodies or immunoreactive fragments of monoclonal antibodies, these antibodies are screened to ensure that antigen binding has not been disrupted. This may be accomplished by any of a variety of means known in the art, but one convenient method would involve use of a phage display library. As will be appreciated by one of skill in the art, as used herein, `immunoreactive fragment` refers in this context to an antibody fragment reduced in length compared to the wild-type or parent antibody which retains an acceptable degree or percentage of binding activity to the target antigen. As will be appreciated by one of skill in the art, what is an acceptable degree will depend on the intended use.

[0032] It is of note hat as discussed herein, any of the above-described antibody or humanized variant thereof may be formulated into a pharmaceutical treatment for providing passive immunity for individuals suspected of or at risk of developing hemorrhagic fever comprising a therapeutically effective amount of said antibody. The pharmaceutical preparation may include a suitable excipient or carrier. See, for example, Remington: The Science and Practice of Pharmacy, 1995, Gennaro ed. As will be apparent to one knowledgeable in the art, the total dosage will vary according to the weight, health and circumstances of the individual as well as the efficacy of the antibody.

[0033] While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made therein, and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.

TABLE-US-00002 TABLE 1 Dose-dependent protective efficacy of McAbs in mice Dose Meantime to Treatment.sup.a (.mu.g/treatment) death.sup.b No. of survivors/total McAb 4G7 100 7.00 (n = 1) 5/6 50 7.00 (n = 1) 5/6 25 6.00 (n = 3) 3/6 12.5 6.80 (n = 5) 1/6 6.25 8.20 (n = 5) 2/6 McAb 5D2 100 N/A.sup.c 6/6 50 N/A.sup.c 6/6 25 N/A.sup.c 6/6 12.5 N/A.sup.c 6/6 6.25 7.50 (n = 2) 4/6 McAb 5E6 100 N/A.sup.c 6/6 50 N/A.sup.c 6/6 25 N/A.sup.c 6/6 12.5 6.50 (n = 2) 4/6 6.25 6.67 (n = 3) 3/6 McAb 7C9 100 N/A.sup.c 6/6 50 N/A.sup.c 6/6 25 7.00 (n = 1) 5/6 12.5 7.00 (n = 1) 5/6 6.25 6.50 (n = 4) 2/6 McAb 7G4 100 N/A.sup.c 6/6 50 7.50 (n = 1) 4/6 25 7.00 (n = 1) 5/6 12.5 7.60 (n = 5) 1/6 6.25 6.60 (n = 5) 1/6 McAb 10C8 100 7.00 (n = 1) 5/6 50 7.00 (n = 1) 5/6 25 7.50 (n = 4) 2/6 12.5 7.00 (n = 5) 1/6 6.25 6.40 (n = 5) 1/6 PBS 5.80 (n = 5) 0/5 .sup.aMice were intraperitoneally treated with antibodies 1 day after challenge with 1000 LD50 of the mouse-adapted Ebola virus. .sup.bData for animals that died (numbers of animals are shown in parentheses). .sup.cN/A: not applicable.

TABLE-US-00003 TABLE 2 Time dependency of the protective efficacy of MAbs in mice MAbs Day of treatment.sup.a Mean time to death.sup.b No. of survivors/total 1H3 -4 6.70 .+-. 0.61 (n = 10) 0/10 100 .mu.g -1 6.60 .+-. 0.61 (n = 10) 0/15 +1 8.10 .+-. 0.74 (n = 9) 6/15 +2 6.60 .+-. 0.80 (n = 5) 5/10 +3 6.40 .+-. 0.97 (n = 10) 0/10 2G4 -4 7.40 .+-. 0.63 (n = 10) 0/10 100 .mu.g -1 7.86 .+-. 0.74 (n = 14) 1/15 +1 8.00 (n = 6) 9/15 +2 7.30 .+-. 0.47 (n = 3) 7/10 +3 5.70 .+-. 1.13 (n = 10) 0/10 4G7 -4 7.42 .+-. 0.46 (n = 7) 3/10 100 .mu.g -1 7.08 .+-. 0.74 (n = 14) 1/15 +1 8.25 .+-. 0.43 (n = 4) 11/15 +2 n/a.sup.c 10/10 +3 5.67 .+-. 1.34 (n = 9) 1/10 5D2 -4 7.00 (n = 1) 9/10 100 .mu.g -1 8.00 .+-. 1.00 (n = 2) 13/15 +1 n/a 15/15 +2 7.00 (n = 4) 6/10 +3 6.30 .+-. 1.05 (n = 10) 0/10 5E6 -4 7.00 (n = 2) 8/10 100 .mu.g -1 8.25 .+-. 0.43 (n = 4) 11/15 +1 7.00 (n = 1) 14/15 +2 6.00 (n = 1) 9/10 +3 5.80 .+-. 1.03 (n = 10) 0/10 7C9 -4 7.00 (n = 1) 9/10 100 .mu.g -1 7.75 .+-. 0.43 (n = 4) 11/15 +1 8.00 .+-. 0.82 (n = 3) 12/15 +2 7.00 (n = 1) 9/10 +3 6.10 .+-. 0.67 (n = 10) 0/10 7G4 -4 8.20 .+-. 0.71 (n = 10) 0/10 100 .mu.g -1 8.07 .+-. 0.59 (n = 14) 1/15 +1 n/a 15/15 +2 7.10 .+-. 0.57 (n = 9) 1/10 +3 6.70 .+-. 0.44 (n = 10) 0/10 10C8 -4 7.83 .+-. 0.64 (n = 6) 4/10 100 .mu.g -1 7.64 .+-. 1.17 (n = 14) 1/15 +1 8.50 .+-. 0.50 (n = 2) 13/15 +2 6.83 .+-. 0.37 (n = 6) 4/10 +3 6.30 .+-. 1.13 (n = 10) 0/10 17F8.sup.d -4 6.00 .+-. 1.10 (n = 9) 1/10 100 .mu.g -1 6.13 .+-. 0.88 (n = 15) 0/15 +1 7.21 .+-. 0.86 (n = 14) 1/15 +2 6.10 .+-. 0.83 (n = 10) 0/10 +3 6.00 .+-. 1.13 (n = 10) 0/10 PBS -4 5.40 .+-. 1.43 (n = 10) 0/10 -1 6.60 .+-. 0.80 (n = 5) 0/5 +3 5.00 .+-. 0.60 (n = 10) 0/10 .sup.aMice were intraperitoneally treated with each MAb at indicated time before or after challenge with 1000 LD50 of the mouse-adapted Ebola virus. .sup.bData for animals that died (numbers of animals are shown in parentheses). .sup.cN/A: not applicable. .sup.dControl Mab: anti-MAR GP.

TABLE-US-00004 TABLE 3 Protective efficacy of MAbs in guinea pigs Day of Meantime No. Treatment treatment.sup.a to death.sup.b of survival/Tatal.sup.c Cocktail of 5D2(3 mg) + 1 N/A.sup.d 6/6 4G7(2 mg) + 1H3(1 mg) + 2 2GA(1 mg) Cocktail of 5E6(3 mg) + 1 N/A 6/6 4G7(2 mg) + 1H3(1 mg) + 2 2G4(1 mg) Cocktail of 7C9(3 mg) + 1 N/A 6/6 4G7(2 mg) + 1H3(1 mg) + 2 2G4(1 mg) Cocktail of 7G4(3 mg) + 1 N/A 6/6 4G7(2 mg) + 1H3(1 mg) + 2 2G4(1 mg) Cocktail of 10C8(3 mg) + 1 9.00 (n = 1) 5/6 4G7(2 mg) + 1H3(1 mg) + 2 2G4(1 mg) Cocktail of PBS + 1 7.00 (n = 6) 0/6 PBS 2 .sup.aGuinea pigs were intraperiotoneally treated with the MAbs as showed dose in the table on the indicated days after challenge with 1000 LD.sub.50 of the guinea pig-adapted Ebola virus. .sup.bData for all animals that died(numbers of animals are shown in parentheses). .sup.cSurvival rate on day 28 after challenge. .sup.dN/A: not applicable.

TABLE-US-00005 TABLE 4 Summary of ELISA Result of Anti-Ebola-GP McAbs Antigen Rf-GP1 Mucin eGP1,2 sGP sub-f-D domain GP1 McAb Isotype eVLPs .DELTA.Tm 1-295aa 157-369aa 333-458aa 1-501aa 1H3 IgG2a, .kappa. + + + - - + 2G4 IgG2b, .kappa. + + - - - - 4G7 IgG2a, .kappa. + + - - - + 5D2 IgG2a, .kappa. + + - + + + 5E6 IgG2a, .lamda. + + - - + + 7C9 IgG2a, .kappa. + + - +/- + + 7G4 IgG1, .kappa. + + - - +/- + 10C8 IgG2a, .kappa. + + - - +/- + Antigens (0.3 .mu.g/well) were coated in 96 well microtitre plate then blocking with 2% skim milk. Serial dilutions of each MAb were applied to the plate followed by HRP-conjugated goat anti-mouse IgG. After incubabing with substrate, the asorbance awas read at OD405. Cut off was 2X background.

TABLE-US-00006 TABLE 5 Prolonged survival seen in McAb-treated Guinea pigs Treatment.sup.a Mean time to death.sup.b Student's t-test MAb 1H3 11.7 .+-. 2.18 (n = 5) p = 0.0181 MAb 2G4 11.5 .+-. 1.50 (n = 2) N/A.sup.c MAb 4G7 10.5 .+-. 1.50 (n = 2) N/A.sup.c MAb 5D2 9.4 .+-. 1.02 (n = 5) p = 0.0244 MAb 5E6 10.8 .+-. 1.47 (n = 5) p = 0.0092 MAb 7C9 9.6 .+-. 0.80 (n = 5) p = 0.0056 MAb 7G4 9.6 .+-. 0.80 (n = 5) p = 0.0056 MAb 10C8 9.4 .+-. 1.20 (n = 5) p = 0.0428 PBS 7.67 .+-. 0.75 (n = 6) N/A.sup.c .sup.aGuinea pigs were intraperiotoneally treated with 5 mg of the MAb as showed in the table on day 1 after challenge with 1000 LD.sub.50 of the guinea pig-adapted Ebola virus. .sup.bData for all animals that died (numbers of animals are shown in parentheses). .sup.cN/A: not applicable.

TABLE-US-00007 TABLE 6 Protective efficacy of MAbs in guinea pigs No. Day of of survival/ Treatment treatment.sup.a Meantime to death.sup.b Tatal.sup.c Cocktail of 4G7(2 mg) + -1 11.17 .+-. 3.09 (n = 3) 3/6 1H3(1.5 mg) + 2G4(1.5 mg) Cocktail of 4G7(2 mg) + +1 7.92 .+-. 0.42 (n = 3) 3/6 1H3(1.5 mg) + 2G4(1.5 mg) Cocktail of 4G7(2 mg) + +2 N/A.sup.d 6/6 1H3(1.5 mg) + 2G4(1.5 mg) Cocktail of 4G7(2 mg) + +3 11.17 .+-. 3.09 (n = 3) 4/6 1H3(1.5 mg) + 2G4(1.5 mg) PBS +2 6.58 .+-. 0.59 (n = 6) 3/6 .sup.aGuinea pigs were intraperiotoneally treated with the MAbs as showed dose in the table on the indicated days before or after challenge with 1000 LD50 of the guinea pig-adapted Ebola virus. .sup.bData for all animals that died(numbers of animals are shown in parentheses). .sup.cSurvival rate on day 28 after challenge. .sup.dN/A: not applicable.

TABLE-US-00008 TABLE 7 Epitopes bound by ZEbov GP MoAbs Ebota GPs epitope epitope mAb name with epitope sequence position IH3(IgG2a/.kappa.): sGP.sup.a SNTTGKLIWKVNPEI 267-280 aa 2G4(IgG2b/.kappa.): GP2.sup.a REAIVNAQPKCNPNL 502-516 aa 4G7(IgG2a/.kappa.): GP2.sup.a REAIVNAQPKCNPNL 502-516 aa 5D2(IgG2a/.kappa.): GP1.sup.b,c,d DPGTNTTTEDHKIMA 329-343 aa 5E6(IgG2a/.kappa.): GP1.sup.b,c,d ATQVEQHHRRTDNDS 401-415 aa 7C9(IgG2a/.lamda.): GP1.sup.b,c unknown unknown 7G4(IgG1, .kappa.): GP1.sup.b,c unknown unknown 10C8(IgG2a, .kappa.): GP1.sup.b,c unknown unknown .sup.adetermined by using recombinant vesicular stamatitis virus(VSV) containing ZEbov GP gene to identify the amino acid changes in antigenic variants that escape antibody neutralization; .sup.bdetermined by Western blot reactivity with Ebola Zaire 1976 or VLPs, .sup.cdetermined by ELISA using recombinant GP1 protein; .sup.ddetermined by ELISA using peptide library.

Sequence CWU 1

1

211373DNAmouse 1tggggcagag cttgtgaagc caggggcctc agtcaagttg tcctgcacag cttctggctt 60caacattaaa gacacctata tacattgggt gaaacagggg cctgaacagg gcctggagtg 120gattggaagg attgatcctg cgaatggtaa tactaaatat gacccgaagt tccagggcaa 180ggccactatc acagcagaca catcctccaa tacagcctac ctgcagctca gcggcctgac 240atctgaggac actgccgtct attactgtgc tagggagtcg aggatatcta ctatgcttac 300gacggggtac tttgactact ggggccaagg caccactctc acagtctcct cagccaaaac 360aacagcccca tcg 3732303DNAmouse 2gcaatcatgt ctgcatctcc aggggagaag gtcaccatga cctgcagtgc cagctcaagt 60gtaagttaca tgtactggta ccagcagaag ccaggatcct cccccagact cctgatttat 120gacacatcca acctggcttc tggagtccct gttcgcttca gtggcagtgg gtctgggacc 180tcttactctc tcacaatcag ccgaatggag gctgaagatg ctgccactta ttactgccag 240cagtggagta gttacccgta cacgttcgga ggggggacca agctggaaat aaaacgggct 300gat 3033364DNAmouse 3tggaggaggc ttgatgcaac ctggaggatc catgaaactc tcctgtgttg cctcaggatt 60cactttcagt aactactgga tgaactgggt ccgccagtct ccagagaagg ggcttgagtg 120ggttgctgaa attagattga aatctaataa ttatgcaaca cattatgcgg agtctgtgaa 180agggaggttc accatttcaa gagatgattc caaaaggagt gtctacctgc aaatgaatac 240cttaagagct gaagacactg gcatttatta ctgtacccgg gggaatggta actacagggc 300tatggactac tggggtcaag gaacctcagt caccgtctcc tcagccaaaa caacaccccc 360atca 3644306DNAmouse 4gcctccctat ctgtatctgt gggagaaact gtctccatca catgtcgagc aagtgagaat 60atttacagta gtttagcatg gtatcagcag aaacagggaa aatctcctca gctcctggtc 120tattctgcaa caatcttagc agatggtgtg ccatcaaggt tcagtggcag tggatcaggc 180actcagtatt ccctcaagat caacagcctg cagtctgaag attttgggac ttattactgt 240caacattttt ggggtactcc gtacacgttc ggagggggga ccaagctgga aataaaacgg 300gctgat 3065358DNAmouse 5tggacctgag ctggagatgc ctggcgcttc agtgaagata tcctgcaagg cttctggttc 60ctcattcact ggcttcagta tgaactgggt gaagcagagc aatggaaaga gccttgagtg 120gattggaaat attgatactt attatggtgg tactacctac aaccagaaat tcaagggcaa 180ggccacattg actgtggaca aatcctccag cacagcctac atgcagctca agagcctgac 240atctgaggac tctgcagtct attactgtgc aagatcggcc tactacggta gtacttttgc 300ttactggggc caagggactc tggtcactgt ctctgcagcc aaaacaacag ccccatcg 3586306DNAmouse 6gcctccctat ctgcatctgt gggagaaact gtcaccatca catgtcgagc aagtgagaat 60atttacagtt atttagcatg gtatcagcag aaacagggaa aatctcctca gctcctggtc 120tataatgcca aaaccttaat agagggtgtg ccatcaaggt tcagtggcag tggatcaggc 180acacagtttt ctctgaagat caacagcctg cagcctgaag attttgggag ttatttctgt 240caacatcatt ttggtactcc attcacattc ggctcgggga cagagttgga aataaaacgg 300gctgat 3067340DNAmouse 7gggacctggc ctggtgagac cttctcagtc tctgtccctc acctgcactg tcactggcta 60ctcaatcacc agtgattatg cctggaactg gatccggcag tttccaggaa acaaactgga 120gtggctgggc tatataacca acactggtag cactggcttc aacccatctc tcaaaagtcg 180aatctctatc actcgagaca catccaagaa ccagttcttc ctgcagttga tttctgtgac 240tactgaggac acagccacat atcactgtgc aaggggcctt gcttactggg gccaagggac 300tctggtcact gtctctgcag ccaaaacaac agccccatcg 3408321DNAmouse 8ctcactttgt cggttaccat tggacaacca gcctccatct cttgcaagtc aagtcagagc 60ctcttagata gtgatggaaa gacatatctg aattggttgt tacagaggcc aggccagtct 120ccaaagcgcc taatctatct ggtgtctaaa ctggactctg gagtcactga caggttcact 180ggcagtggat cagggacaga tttcacactg aaaatcagca gagtggaggc tgaggatttg 240ggagtttatt attgttggca aggtacacac tctccattca cgttcggctc ggggacaaag 300ttggaaataa aacgggctga t 3219370DNAmouse 9tgggggaggc ttagtgaagc ctggagggtc cctgaaactc tcctgtgcag cctctggatc 60cgctttcagt agatatgaca tgtcttgggt tcgccagact ccggagaaga ggctggagtg 120ggtcgcatac attagtcgtg gtggtggttt catctactat ccagacactg tgaagggccg 180attcaccatc tccagagaca atgccaagaa caccctgtac ctgcaaatga gcagtctgaa 240gtctgacgac acagccatgt attactgtgc aagacacgtt tactacggta gtagccccct 300ctatgctatg gactactggg gtcaaggaac ctcagtcacc gtctcctcag ccaaaacaac 360agccccatcg 37010324DNAmouse 10tcagcctctt tctccctggg agcctcagca aaactcacgt gcaccttgag tagtcagcac 60agtacgttca ccattgaatg gtatcagcaa cagccactca agcctcctaa gtatgtgatg 120gagcttaaga aagatggaag ccacagtaca ggtgatggga ttcctgatcg cttctctgga 180tccagctctg gtgctgatcg ctaccttagc atttccaaca tccagcctga agatgaagca 240atatacatct gtggtgtggg tgatacaatt aatgaacaat ttgtgtatgt tttcggcggt 300ggaaccaagg tcactgtcct aggt 32411358DNAmouse 11tggggcagag cttgtgaagc caggggcctc agtcaagttg tcctgcacag cttctggctt 60caacattaaa gacacctata tgcactgggt gaaggagagg cctgacaagg gcctggagtg 120gattggaagg attgatccag cgaatggtaa tactaaatgt gactcgaggt ttcagggcaa 180ggccactata acagcagaca catcctccaa cacagcctac ctgcagctca gcagcctgac 240atctgaggac actgccgtct attactgtgc tagaaggatc tactttggta agggctttga 300cttttggggc caaggcacca ctctcacagt ctcctcagcc aaaacaacag ccccatcg 35812324DNAmouse 12tcctccctga gtgtgtcagc aggagagaag gtcactatga gctgcaagtc cagtcagagt 60ctgtttaaca gtggagatca aaagaactac ttggcctggt accagcagaa accagggcag 120cctcctaaac tgttgatcta cggggcatcc actagggaat ctggggtccc tgatcgcttc 180acaggcagtg gatctggaac cgatttcact cttaccatca gcagtgtgca ggctgaagac 240ctggcagttt attactgtca gaatgatcaa ttttatcctc ccacgttcgg tgatgggacc 300aagctggacc tgaaacgggc tgat 32413367DNAmouse 13tggagggggc ttggtacagc ctgggggttc tctgagactc tcctgtgcaa cttctggctt 60cacctttact gatcactaca tgggctgggt ccgccagcct ccaggaaagg cacttgagtg 120gttggctttt gttagataca aagctaaggg ttacacaaca gagtacactg catctgtgaa 180gggtcggttc accatctcca gagataattc ccaaagcatc ctctatcttc aaatgaacac 240cctgagaact gaggacagtg ccacttatta ctgtgcaaga gatagagggg gttacgtggg 300agctatggac tactggggtc aaggaacctc agtcaccgtc tcctcagcca aaacgacacc 360cccatct 36714321DNAmouse 14ctctccctgc ctgtcagtct tggagatcaa gcctccatct cttgcagatc tagtcagagc 60cttgtacaca ggaatggaaa cacctatttc cattggtacc tgcagaagcc aggccagtct 120ccaaaactcc tgatctacaa agtttccaac cgattttctg gggtcccaga caggttcagt 180ggcagtggat cagggacaga tttcacactc aagatcagca gagtggaggc tgaggatctg 240ggagtttatt tctgctctca aagtacacat gttccgtaca ctttcggagg ggggaccaag 300ctggaaataa aacgggctga t 32115352DNAmouse 15tggggcagag cttgtgaggt caggggcctc agtcaagttg tcctgcacat cttctggctt 60caacattaaa gactactttc tacactgggt gaaacagagg cctgaacagg gcctggagtg 120gattggatgg attgatcctg agaatggtga tactgaatat gccccgaagt tccaggacaa 180ggccactatg actgcagaca catcctccaa cacagcctac ctgcacctca gcagcctgac 240atctgaggac actggcgtct attactgtaa tgcagatggt aactacggga agaactactg 300gggccaaggc accactctca ccgtctcctc agccaaaaca acagccccat cg 35216324DNAmouse 16ctctccctgc ctgtcagtct tggagatcaa gcctccatct cttgcagatc tagtcagagc 60cttgtacaca gtaatggaaa caccttttta cattggtacc tgcagaagcc aggccagtct 120ccaaagctcc tgatctacag agtttccaac cgattttctg gggtcccaga caggttcagt 180ggcagtggat cagggacaga tttcacactc aagatcagca gagtggaggc tgaggatctg 240ggagtttatt tctgctctca aagtacacat gttcctccgt acacgttcgg aggggggacc 300aagctggaaa taaaacgggc tgat 3241715PRTmouse 17Ser Asn Thr Thr Gly Lys Leu Ile Trp Lys Val Asn Pro Glu Ile 1 5 10 15 1815PRTmouse 18Arg Glu Ala Ile Val Asn Ala Gln Pro Lys Cys Asn Pro Asn Leu 1 5 10 15 1915PRTmouse 19Arg Glu Ala Ile Val Asn Ala Gln Pro Lys Cys Asn Pro Asn Leu 1 5 10 15 2015PRTmouse 20Asp Pro Gly Thr Asn Thr Thr Thr Glu Asp His Lys Ile Met Ala 1 5 10 15 2115PRTmouse 21Ala Thr Gln Val Glu Gln His His Arg Arg Thr Asp Asn Asp Ser 1 5 10 15

Claims

1-4. (canceled)

5. A pharmaceutical composition for the treatment of Ebola, the pharmaceutical composition comprising at least a first monoclonal antibody and a second monoclonal antibody, wherein the first monoclonal antibody is selected from a group consisting of: (a) a monoclonal antibody or antigen binding fragment thereof comprising a light chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID NO: 2, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said light chain variable region have been changed or deleted; and a heavy chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID No: 1, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said heavy chain variable region have been changed or deleted; (b) a monoclonal antibody or antigen binding fragment thereof comprising a light chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID NO: 4, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said light chain variable region have been changed or deleted; and a heavy chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID No: 3, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said heavy chain variable region have been changed or delete& and (c) a monoclonal antibody or antigen binding fragment thereof comprising a light chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID NO:6, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said light chain variable region have been changed or deleted; and a heavy chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID No: 5, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said heavy chain variable region have been changed or deleted.

6. The pharmaceutical composition of claim 5, further comprising a pharmaceutically acceptable excipient or carrier.

7. A method of treating a patient suspected of having hemorrhagic fever or at risk of developing hemorrhagic fever, the method comprising: i) identifying such a patient ii) administering a therapeutically effective amount of a pharmaceutical composition comprising at least a first monoclonal antibody and a second monoclonal antibody, wherein the first monoclonal antibody is selected from a group consisting of: (a) a monoclonal antibody or antigen binding fragment thereof comprising a light chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID NO: 2, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said light chain variable region have been changed or deleted and a heavy chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID No: 1, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said heavy chain variable region have been changed or deleted; (b) a monoclonal antibody or antigen binding fragment thereof comprising a light chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID NO: 4, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said light chain variable region have been changed or deleted and a heavy chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID No: 3, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said heavy chain variable region have been changed or deleted; and (c) a monoclonal antibody or antigen binding fragment thereof comprising a light chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID NO: 6, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said light chain variable region have been changed or deleted and a heavy chain variable region comprising the amino acid sequence deduced from the nucleic acid molecule as set forth in SEQ ID No: 5, or variants thereof whereby at least one but fewer than 30 of the amino acid residues of said heavy chain variable region have been changed or deleted.

8. The method of claim 7, wherein the pharmaceutical composition further comprises a pharmaceutically acceptable excipient or carrier.