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Lassa Fever Virus

Table of Contents
  1. General Information
    1. NCBI Taxonomy ID
    2. Disease
    3. Introduction
    4. Microbial Pathogenesis
    5. Host Ranges and Animal Models
    6. Host Protective Immunity
  2. Vaccine Related Pathogen Genes
    1. GPC (Protective antigen)
    2. LASVsSgp1 nucleoprotein (Protective antigen)
    3. LASVsSgp2 glycoprotein (Protective antigen)
  3. Vaccine Information
    1. Lassa fever virus recombinant vector vaccine V-LSG encoding the glycoprotein
    2. Lassa fever virus recombinant vector vaccine V-LSG/N encoding the glycoprotein and the nucleoprotein
    3. Lassa fever virus recombinant vector vaccine YFV17D/LASV-GPC encoding the glycoprotein precursor
    4. Lassa Virus Nucleoprotein Subunit Vaccine
    5. ML29
    6. V-LSG
    7. V-LSG + V-LSN
    8. V-LSG/N
    9. V-LSG1 + V- LSG2
    10. V-LSGPC
    11. V-LSN
    12. VSV[Delta]G/LVGPC
    13. YFV17D/LAS-GPC
  4. References
I. General Information
1. NCBI Taxonomy ID:
11620
2. Disease:
Lassa fever
3. Introduction
Lassa fever is a viral haemorrhagic fever caused by an arenavirus. Arenaviruses produce mostly silent, persistent infection in rodents, and their origin is thought to date back to the evolution of different rodent species, perhaps as much as 9 million years ago. Accidental human exposure to the virus is frequent. Lassa fever begins insidiously, after an incubation period of 7–18 days, with fever, weakness, malaise, severe headache, and a very painful sore throat. Up to a third of hospitalized Lassa fever patients progress to a prostrating illness 6–8 days after onset of fever, usually with persistent vomiting and diarrhea. Bleeding is seen in only 15–20% of patients, limited primarily to the mucosal surfaces or occasionally conjunctival haemorrhages or gastrointestinal or vaginal bleeding. Severe pulmonary edema and acute respiratory distress syndrome is common in fatal cases with gross head and neck edema and hypovolemic shock. Lassa fever has considerable long-term sequelae, in that nearly 30% of patients with Lassa fever infection suffer an acute loss of hearing in one or both ears. About half of these patients show a near or complete recovery by 3–4 months after onset, but the other half continue with significant sensorineural deafness, which after about a year will be permanent (Fisher-Hoch et al., 2001).
4. Microbial Pathogenesis
Disease is associated with destruction of antigen specific cytotoxic T lymphocytes (CTLs), causing leukopenia, decreased hemoglobin concentration, elevation of liver aminotransferases, and liver lipidosis. Pathogenesis involves initial replication at the site of infection. Lymph node, lung, and other parenchymal organs are important sites of viral growth. Interstitial infiltrates and edema occur during infection, and the macrophage is early and prominently involved. Many epithelial structures contain antigen and nucleic acids, with widespread marginal zone infection and splenic lymphoid follicle necrosis are common findings (Botten et al., 2006).
5. Host Ranges and Animal Models
The natural host is a small African rat, Mastomys natalensis (Fisher-Hoch et al., 2001).
6. Host Protective Immunity
Detectable neutralizing antibodies are absent during acute Lassa virus infection. Low-titer neutralizing antibodies may appear several weeks to months after the resolution of infection. Treatment of LF patients with immune plasma does not protect against disease. These observations strongly suggest that antibody response is not important, instead, cell-mediated immunity is critical for protection against LASV infection in humans. LASV-specific CD4+ T cells have been found in convalescent patients, and CD8+ T-cell response is the main determinant responsible for providing protection against LASV infection (Botten et al., 2006).
1. GPC
  • Gene Name : GPC
  • Sequence Strain (Species/Organism) : Lassa virus strain AV
  • NCBI Protein GI : 354681511
  • Other Database IDs : CDD:144408
  • Taxonomy ID : 11620
  • Gene Strand (Orientation) : ?
  • Protein Name : GPC protein
  • Protein Length : 491
  • Protein Note : Arenavirus glycoprotein; pfam00798
  • Protein Sequence : Show Sequence
    >gi|354681511|emb|CCA30314.1| GPC protein [Lassa virus]
    MGQIVTFFQEVPHVIEEVMNIVLIALSILAVLKGLYNIATCGLIGLITFLLLCGRSCSSNLYKGVYELQS
    LDLNMETLNMTMPLSCTKNNSHHYIRVGNDTGLELTLTNTSILNHKFCNLSDAHKKDLYDHALMSIISTF
    HLSIPNFNQYEAMSCDFNGGKISVQYNLSHSYAIDAANHCGTVANGILQTFMRMAWGGSYIALDSGRGNW
    DCIMTSYQYLIIQNTTWENHCQFSRPSPIGYLGLLSQRTRDIYISRRLLGTFTWTLSDSEGNATPGGYCL
    TRWMLIEAELKCFGNTAVAKCNEKHDEEFCDMLRLFDFNKQAISRLKSEAQMSIQLINKAVNALINDQLI
    MKNHLRDIMGIPYCNYSKYWYLNHTITGKTSLPKCWLVSNGSYLNETHFSDDIEQQADNMITEMLQKEYM
    ERQGKTPLGLVDLFVFSTSFYLISIFLRLVKIPTHRHIVGKPCPKPHRLNHMGICSCGLYKQPGVPVRWK
    R
  • Molecule Role : Protective antigen
  • Related Vaccine(s): Lassa fever virus recombinant vector vaccine YFV17D/LASV-GPC encoding the glycoprotein precursor
2. LASVsSgp1 nucleoprotein
  • Gene Name : LASVsSgp1 nucleoprotein
  • Sequence Strain (Species/Organism) : Lassa virus strain Josiah
  • VO ID : VO_0011151
  • NCBI Gene ID : 956584
  • NCBI Protein GI : 23343510
  • Locus Tag : LASVsSgp1
  • Genbank Accession : J04324
  • Protein Accession : NP_694869
  • Taxonomy ID : 11620
  • Segment No : segment S
  • Gene Starting Position : 100
  • Gene Ending Position : 1809
  • Gene Strand (Orientation) : +
  • Protein Name : nucleoprotein
  • Protein pI : 8.58
  • Protein Weight : 59623.51
  • Protein Length : 569
  • DNA Sequence : Show Sequence
    >gi|23343509:100-1809 Lassa virus segment S, complete sequence
    GATGAGTGCCTCAAAGGAAATAAAATCCTTTTTGTGGACACAATCTTTGAGGAGGGAATTATCTGGTTAC
    TGCTCCAACATCAAACTACAGGTGGTGAAAGATGCCCAGGCTCTTTTACATGGACTTGACTTCTCCGAAG
    TCAGTAATGTTCAACGGTTGATGCGCAAGGAGAGAAGGGATGACAATGATTTGAAACGGTTGAGGGACCT
    AAATCAAGCGGTCAACAATCTTGTTGAATTAAAATCAACTCAACAAAAGAGTATACTGAGAGTTGGGACT
    CTAACCTCAGATGACTTATTAATCTTAGCCGCTGATCTAGAGAAGTTAAAGTCAAAGGTGATCAGAACAG
    AAAGGCCATTAAGTGCAGGTGTCTATATGGGCAACCTAAGCTCACAGCAACTTGACCAAAGAAGAGCTCT
    CCTGAATATGATAGGAATGAGTGGTGGTAATCAAGGGGCTCGGGCTGGGAGAGATGGAGTGGTGAGAGTT
    TGGGATGTGAAAAATGCAGAGTTGCTCAATAATCAGTTCGGGACCATGCCAAGTCTGACACTGGCATGTC
    TGACAAAACAGGGGCAGGTTGACTTGAATGATGCAGTACAAGCATTGACAGATTTGGGTTTGATCTACAC
    AGCAAAGTATCCCAACACTTCAGACTTAGACAGGCTGACTCAAAGTCATCCCATCCTAAATATGATTGAC
    ACCAAGAAAAGCTCTTTGAATATCTCAGGTTATAATTTTAGCTTGGGTGCAGCTGTGAAGGCAGGAGCTT
    GCATGCTGGATGGTGGCAATATGTTGGAGACAATCAAGGTGTCACCTCAGACAATGGATGGTATCCTCAA
    ATCCATTTTAAAGGTCAAGAAGGCTCTTGGAATGTTCATTTCAGACACCCCTGGTGAAAGGAATCCTTAT
    GAAAACATACTCTACAAGATTTGTTTGTCAGGAGATGGATGGCCATATATTGCATCAAGAACCTCAATAA
    CAGGAAGGGCCTGGGAAAACACTGTCGTTGATCTGGAATCAGATGGGAAGCCACAGAAAGCTGACAGCAA
    CAATTCCAGTAAATCCCTGCAGTCGGCAGGGTTTACCGCTGGGCTTACCTATTCTCAGCTGATGACCCTC
    AAGGATGCAATGCTGCAACTTGACCCAAATGCTAAGACCTGGATGGACATTGAAGGAAGACCTGAAGATC
    CAGTGGAAATTGCCCTCTATCAACCAAGTTCAGGCTGCTACATACACTTCTTCCGTGAACCTACTGATTT
    AAAGCAGTTCAAGCAGGATGCTAAGTACTCACATGGGATTGATGTCACAGACCTCTTCGCTACACAACCG
    GGCTTGACCAGTGCTGTCATTGATGCACTCCCCCGGAATATGGTCATTACCTGTCAGGGGTCCGATGACA
    TAAGGAAACTCCTTGAATCACAAGGAAGAAAAGACATTAAACTAATTGATATTGCCCTCAGCAAAACTGA
    TTCCAGGAAGTATGAAAATGCAGTCTGGGACCAGTATAAAGACTTATGCCACATGCACACAGGTGTCGTT
    GTTGAAAAGAAGAAAAGAGGCGGTAAAGAGGAAATAACCCCTCACTGTGCACTAATGGACTGCATCATGT
    TTGATGCAGCAGTGTCAGGAGGACTGAACACATCGGTTTTGAGAGCAGTGCTGCCCAGAGATATGGTGTT
    CAGAACATCGACACCTAGAGTCGTTCTGTA
  • Protein Sequence : Show Sequence
    >gi|23343510|ref|NP_694869.1| nucleoprotein [Lassa virus]
    MSASKEIKSFLWTQSLRRELSGYCSNIKLQVVKDAQALLHGLDFSEVSNVQRLMRKERRDDNDLKRLRDL
    NQAVNNLVELKSTQQKSILRVGTLTSDDLLILAADLEKLKSKVIRTERPLSAGVYMGNLSSQQLDQRRAL
    LNMIGMSGGNQGARAGRDGVVRVWDVKNAELLNNQFGTMPSLTLACLTKQGQVDLNDAVQALTDLGLIYT
    AKYPNTSDLDRLTQSHPILNMIDTKKSSLNISGYNFSLGAAVKAGACMLDGGNMLETIKVSPQTMDGILK
    SILKVKKALGMFISDTPGERNPYENILYKICLSGDGWPYIASRTSITGRAWENTVVDLESDGKPQKADSN
    NSSKSLQSAGFTAGLTYSQLMTLKDAMLQLDPNAKTWMDIEGRPEDPVEIALYQPSSGCYIHFFREPTDL
    KQFKQDAKYSHGIDVTDLFATQPGLTSAVIDALPRNMVITCQGSDDIRKLLESQGRKDIKLIDIALSKTD
    SRKYENAVWDQYKDLCHMHTGVVVEKKKRGGKEEITPHCALMDCIMFDAAVSGGLNTSVLRAVLPRDMVF
    RTSTPRVVL
  • Molecule Role : Protective antigen
  • Molecule Role Annotation : Vaccine efficacy trials in guinea pigs indicated that the nucleoprotein is capable of eliciting a protective immune response against a lethal dose of Lassa virus. Ninety-four percent of the animals vaccinated with V-LSN survived a Lassa virus challenge in which only 14% of unvaccinated animals and 39% of animals vaccinated with the New York Board of Health (NYBH) strain of vaccinia virus survived (Morrison et al., 1989).
  • Related Vaccine(s): Lassa fever virus recombinant vector vaccine V-LSG/N encoding the glycoprotein and the nucleoprotein , Lassa Virus Nucleoprotein Subunit Vaccine
3. LASVsSgp2 glycoprotein
  • Gene Name : LASVsSgp2 glycoprotein
  • Sequence Strain (Species/Organism) : Lassa virus strain Josiah
  • VO ID : VO_0010869
  • NCBI Gene ID : 956585
  • NCBI Protein GI : 23343511
  • Locus Tag : LASVsSgp2
  • Genbank Accession : J04324
  • Protein Accession : NP_694870
  • Taxonomy ID : 11620
  • Segment No : segment S
  • Gene Starting Position : 1871
  • Gene Ending Position : 3346
  • Gene Strand (Orientation) : -
  • Protein Name : glycoprotein
  • Protein pI : 7.63
  • Protein Weight : 53529.32
  • Protein Length : 491
  • DNA Sequence : Show Sequence
    >gi|23343509:1871-3346 Lassa virus segment S, complete sequence
    CTCATCTCTTCCATTTCACAGGCACACCAGGCTGTTTGTAGAGTCCACAGGAACAAATGCCCATATGATT
    CAATCTGTGAGGTTTGGGACACGACTTGCCTACAATATGCCTATGAGTTGGTATTTTGACTAGGTGAAGG
    AAGATGCTAATAAGATAGAAACTTGTACTGAACACAAAGAGGTCAACTAGACCCAATGGTGTCTTCCCCT
    GCCTCTCCATATACTCCTTCTGTAACATCTCAGTGATCATATTGTCAGCTTGTTGTTCAATATCATCAGA
    AAAGTGGGTCTCGTTCAAGTATGAACCATTTGATACAAGCCAACATTTGGGCAGTGATGTTCTCCCAGTA
    GTTGTGTGGTTGAGGTACCAATACTTGCTGTAATTACAGTATGGAATTCCCATGATGTCCCGTAGATGGT
    TCTTCATTATAAGTTGGTCATTTATCAAAGCATTTACTGCTTTGTTGATCAACTGAATGCTCATTTGTGC
    TTCAGCTTTCAACCTTTGAATGGCTTGTTTGTTGAAGTCAAACAGCCTCAGCATGTCACAAAATTCCTCA
    TCATGCTTCTCATTACATTTTGCCACAGCTGTGTTCCCGAAGCATTTTAGTTCAGCCTCAATTAGCATCC
    ACCTGGTCAGACAATATCCCCCTGGTGTGTCTTTACCTTCAGAATCTGACAGTGTCCATGTGAATGTGCC
    TAGCAATCTTCTACTAATATAAATATCTCTAGTCCTTTGTGAGAGGAGCCCGAGATAACCGATGGGAGAT
    GGTCTCGAGAATTGGCAGTGATCTTCCCAGGTTGTATTTTGGATTATCAGATATTGATAACTAGTCATAA
    TACAGTCCCAGTTGCCACGGCCTGAGTCAAGAGCAATGTAGCTCCCACCCCAAGCCATCCTCATAAAAGT
    CTGTAACACACCATTTGCAACAGTACCACAATGGTTGGCTGCATCCCCAGCATAGCTGTGACTCAGGTTG
    TACTGCACACTAATCTTTCCCCCATTAAAATCGCAGCTCATTGCCTCATACTGATTGAAGTTGGGGATGG
    ACAAGTGGAAAGTTGAGATTATGCTCATAAGAGCGTGGTCATAGAGGTTCTTTTTGTGGGCATCAGACAG
    ATTGCAAAATTTGTGATTAATAATGCTCGTGTTGGTCAAGGTCAGTTCTAGTCCTGTCTCATTGCCCACC
    ATTATATAATGATGACTGTTGTTCTTTGTGCAGGAGAGAGGCATGGTCATATTGAGTGTCTCCATGTTTA
    GTTCCAGAGTCTGAAGCTCATAAACCCCTTTATAAAGACTGGTTGTGCAAGACCTACCACACAACAGGAG
    GAAAGTGACCAAACCAACAAGGCCACACGTTGCAAAATTGTACAGACCTTTCAGCACTGCTAGTACAGAC
    AGTGCAATGAGAACAATGTTCATCACCTCTTCTATTACATGAGGCACTTCCTGGAAGAATGTCACTATTT
    GTCCCA
  • Protein Sequence : Show Sequence
    >gi|23343511|ref|NP_694870.1| glycoprotein [Lassa virus]
    MGQIVTFFQEVPHVIEEVMNIVLIALSVLAVLKGLYNFATCGLVGLVTFLLLCGRSCTTSLYKGVYELQT
    LELNMETLNMTMPLSCTKNNSHHYIMVGNETGLELTLTNTSIINHKFCNLSDAHKKNLYDHALMSIISTF
    HLSIPNFNQYEAMSCDFNGGKISVQYNLSHSYAGDAANHCGTVANGVLQTFMRMAWGGSYIALDSGRGNW
    DCIMTSYQYLIIQNTTWEDHCQFSRPSPIGYLGLLSQRTRDIYISRRLLGTFTWTLSDSEGKDTPGGYCL
    TRWMLIEAELKCFGNTAVAKCNEKHDEEFCDMLRLFDFNKQAIQRLKAEAQMSIQLINKAVNALINDQLI
    MKNHLRDIMGIPYCNYSKYWYLNHTTTGRTSLPKCWLVSNGSYLNETHFSDDIEQQADNMITEMLQKEYM
    ERQGKTPLGLVDLFVFSTSFYLISIFLHLVKIPTHRHIVGKSCPKPHRLNHMGICSCGLYKQPGVPVKWK
    R
  • Molecule Role : Protective antigen
  • Molecule Role Annotation : HLA-A*0201 mice immunized with either GPC(42-50) from LASVsSgp2 glycoprotein or GPC(60-68) were protected against challenge with a recombinant vaccinia virus that expressed LASV GPC (Botten et al., 2006).
  • Related Vaccine(s): Lassa fever virus recombinant vector vaccine V-LSG encoding the glycoprotein , Lassa fever virus recombinant vector vaccine V-LSG/N encoding the glycoprotein and the nucleoprotein , V-LSGPC , VSV[Delta]G/LVGPC
III. Vaccine Information
1. Lassa fever virus recombinant vector vaccine V-LSG encoding the glycoprotein
a. Vaccine Ontology ID:
VO_0004378
b. Type:
Recombinant vector vaccine
c. Status:
Research
d. Host Species as Laboratory Animal Model:
Macaque
e. Gene Engineering of LASVsSgp2 glycoprotein
  • Type: Recombinant vector construction
  • Description: Vector NYBH strains of vaccinia virus expressed the uncleaved, full-length glycoprotein (Fisher-Hoch et al., 2000).
  • Detailed Gene Information: Click here.
f. Vector:
NYBH strains of vaccinia virus (Fisher-Hoch et al., 2000)
g. Immunization Route
Intramuscular injection (i.m.)
h. Monkey Response
  • Vaccine Immune Response Type: VO_0000286
  • Immune Response: The protection of our animals by Lassa virus glycoprotein expressed in vaccinia virus in the face of a low antibody response supports that antibody alone does not provide protection. Proper folding of LCMV glycoprotein is critical for induction of the humoral response and vaccinia virus-expressed glycoproteins are not posttranslationally processed or transported correctly to the membrane. Thus, the minimal measurable antibody response to glycoprotein after vaccination may be related to improperly folded glycoprotein (Fisher-Hoch et al., 2000).
  • Efficacy: 8 of 9 V-LSG-vaccinated animals survived Lassa virus challenge (Fisher-Hoch et al., 2000).
2. Lassa fever virus recombinant vector vaccine V-LSG/N encoding the glycoprotein and the nucleoprotein
a. Vaccine Ontology ID:
VO_0004379
b. Type:
Recombinant vector vaccine
c. Status:
Research
d. Host Species as Laboratory Animal Model:
Macaque
e. Gene Engineering of LASVsSgp1 nucleoprotein
  • Type: Recombinant vector construction
  • Description: Vector NYBH strains of vaccinia virus expressed the nucleoprotein (Fisher-Hoch et al., 2000).
  • Detailed Gene Information: Click here.
f. Gene Engineering of LASVsSgp2 glycoprotein
  • Type: Recombinant vector construction
  • Description: Vector NYBH strains of vaccinia virus expressed the glycoprotein (Fisher-Hoch et al., 2000).
  • Detailed Gene Information: Click here.
g. Vector:
NYBH strains of vaccinia virus (Fisher-Hoch et al., 2000)
h. Immunization Route
Intramuscular injection (i.m.)
i. Monkey Response
  • Vaccine Immune Response Type: VO_0000286
  • Immune Response: The protection of our animals by Lassa virus glycoprotein expressed in vaccinia virus in the face of a low antibody response supports that antibody alone does not provide protection. Proper folding of LCMV glycoprotein is critical for induction of the humoral response and vaccinia virus-expressed glycoproteins are not posttranslationally processed or transported correctly to the membrane. Thus, the minimal measurable antibody response to glycoprotein after vaccination may be related to improperly folded glycoprotein (Fisher-Hoch et al., 2000).
  • Efficacy: 9 of 10 monkeys that received the V-LSG/N vaccine survived challenge with Lassa virus (Fisher-Hoch et al., 2000).
3. Lassa fever virus recombinant vector vaccine YFV17D/LASV-GPC encoding the glycoprotein precursor
a. Vaccine Ontology ID:
VO_0004380
b. Type:
Recombinant vector vaccine
c. Status:
Research
d. Host Species as Laboratory Animal Model:
Guinea pig
e. Gene Engineering of GPC
  • Type: Recombinant vector construction
  • Description: Vector Yellow Fever Vaccine 17D (YFV17D) expressed the Lassa virus glycoprotein precursor (LASV-GPC) (Bredenbeek et al., 2006).
  • Detailed Gene Information: Click here.
f. Vector:
Yellow Fever Vaccine 17D (YFV17D) (Bredenbeek et al., 2006)
g. Immunization Route
Intramuscular injection (i.m.)
h. Guinea pig Response
  • Vaccine Immune Response Type: VO_0000286
  • Immune Response: The YFV17D/LAS-GPC vaccination elicited humoral immune responses against YFV17D and LASV antigens. Neutralizing antibodies play the major role in protection against yellow fever (Bredenbeek et al., 2006).
  • Efficacy: A single subcutaneous injection of the recombinant vaccine protected 13 guinea pigs against fatal Lassa Fever (Bredenbeek et al., 2006).
4. Lassa Virus Nucleoprotein Subunit Vaccine
a. Vaccine Ontology ID:
VO_0011441
b. Type:
Recombinant vector vaccine
c. Status:
Research
d. Gene Engineering of LASVsSgp1 nucleoprotein
  • Type: Recombinant vector construction
  • Description:
  • Detailed Gene Information: Click here.
e. Vector:
Vaccinia virus (Morrison et al., 1989).
f. Immunization Route
Intradermal injection (i.d.)
g. Guinea pig Response
  • Vaccination Protocol: Control animals received either no vaccine or 108 PFU of NYBH vaccinia; vaccinated animals received108 PFU of V-LSGPC or V-LSN, or a simultaneous injection with both recombinant vaccinia viruses at separate sites, by intradermal injection of 0.1 ml on the back (Morrison et al., 1989).
  • Challenge Protocol: Animals were challenged with 104 PFU of guinea-pig-passaged Lassa virus by intraperitoneal inoculation 3 to 4 weeks postvaccination (Morrison et al., 1989).
  • Efficacy: Ninety-four percent of the animals vaccinated with V-LSN survived a Lassa virus challenge in which only 14% of unvaccinated animals and 39% of animals vaccinated with the New York Board of Health (NYBH) strain of vaccinia virus survived (Morrison et al., 1989).
5. ML29
a. Vaccine Ontology ID:
VO_0004085
b. Type:
Attenuated
c. Preparation
Clone ML29 is selected and triple plaque purified. The viruses are grown on Vero E6 cells cultured in Dulbecco's modified minimum Eagle's medium with 2% fetal calf serum, 1% penicillin-streptomycin, and l-glutamine (2 mM) at 37°C in 5% CO2. Cells and virus stocks were free of mycoplasma contamination (Lukashevich et al., 2005).
d. Description
ML29 is a clone that has been isolated from a Mopeia virus (MOPV) and Lassa virus (LASV) reassortant. It contains the L RNA from MOPV and the S RNA segment from LASV (Lukashevich et al., 2005).
e. Guinea pig Response
  • Host Strain: 13
  • Vaccination Protocol: Ten animals were inoculated subcutaneously (s.c.) with the ML29 clone, and 10 guinea pigs received the same dose of MOPV. Eight animals were used as negative controls. At day 30 after vaccination, the animals were s.c. challenged with 103 PFU of LASV (Josiah) and followed for 70 days. Liver enzymes were measured in plasma. Vaccinated animals were euthanized on day 70 after challenge, and tissues were removed (Lukashevich et al., 2005).
  • Persistence: None noted
  • Side Effects: In vaccinated animals, LASV infection did not induce alterations in target tissues. The lungs and livers of vaccinated animals looked essentially like normal tissues. There were also no lesions in other major organs (Lukashevich et al., 2005).
  • Efficacy: All strain 13 guinea pigs vaccinated with clone ML29 survived at least 70 days after LASV challenge without either disease signs or histological lesions (Lukashevich et al., 2005).
  • Description: Infection of strain 13 guinea pigs with MOPV or with the ML29 reassortant was not lethal for the animals and did not induce clinical or biochemical signs of the disease. All animals survived after challenge and had no clinical manifestations. All measured parameters were in normal ranges in ML29-vaccinated guinea pigs. In MOPV-vaccinated animals, a transient elevation of AST and AlkPh in plasma was observed at week 3 after challenge (Lukashevich et al., 2005).
f. Monkey Response
  • Host Strain: Rhesus macaques
  • Vaccination Protocol: Two adult rhesus macaques were s.c. injected with 103 PFU of ML29. Blood samples were taken weekly and submitted to the clinical laboratory for complete blood counts and standard 20-assay chemistry panels. At days 14 and 28, the monkeys were euthanized and total blood and tissues were collected. A portion of each tissue was submerged in MEM with 10% FCS (for plaque titration) and in RNAlater (for RNA isolation). The remaining tissue portions were fixed in 10% neutral formalin for the preparation of standard histological sections and stained with hematoxylin-eosin (Lukashevich et al., 2005).
  • Efficacy: This data indicates that ML29 vaccination of rhesus macaques results in a short, inapparent, self-limited infection (Lukashevich et al., 2005).
  • Description: The ML29-vaccinated animals were afebrile throughout the experiment and had no clinical manifestations. Hematological and chemical parameters were in the normal ranges, as was gross appearance at necropsy. Detailed histological examination of rhesus macaques infected with the ML29 reassortant revealed no tissue lesions. The ML29 virus replicated poorly in monkeys and was not detectable in the plasma and tissues by conventional infectious plaque assay. The only organ from which the virus was recovered was the spleen. RT/PCR with LASV GPC-derived primers was transiently positive with RNA plasma and tissue samples (Lukashevich et al., 2005).
6. V-LSG
a. Vaccine Ontology ID:
VO_0004080
b. Type:
Vaccina virus
c. Preparation
The sequence is derived from the Josiah strain of Lassa virus, isolated from a patient in Sierra Leone (Fisher-Hoch et al., 2000).
d. Virulence
e. Description
V-LSG is a vaccinia viruses expressing the S-segment Lassa glycoprotein (Fisher-Hoch et al., 2000).
f. Monkey Response
  • Host Strain: Rhesus and Cynomolgus
  • Vaccination Protocol: All animals received a single vaccination consisting of 0.2 ml of vaccine given intradermally and simultaneously at four separate sites (each forearm and the lateral aspect of each thigh) at a dilution which delivered to each animal a total dose of 109 PFU. All animals were challenged subcutaneously with 103 to 104 PFU of the Josiah strain of Lassa virus in 0.5 ml of phosphate-buffered saline within 36 to 700 days (Fisher-Hoch et al., 2000).
  • Persistence: The latest day on which virus could be recovered from serum was day 14, and that from tissues was day 21. Evidence for persistence elsewhere in tissues or fluids in survivors could not be found by cocultivation of tissues taken up to 112 days following challenge. However, autopsy and biopsy material examined by RT-PCR revealed that viral RNA could be detected at least 112 days after challenge (Fisher-Hoch et al., 2000).
  • Side Effects: Animals showed little or no disturbance of liver function, even in the face of viremia (Fisher-Hoch et al., 2000).
  • Efficacy: The response to glycoprotein protects these animals from induction of fatal processes leading to disease and death (Fisher-Hoch et al., 2000).
  • Description: 8 of 9 vaccinated animals survived. This protection against death was significant when compared with the death rate of the controls. These animals showed significantly diminished mean virus titers compared with those of unvaccinated animals. The one V-LSG-vaccinated animal that died reached maximum viremia on day 8, and the last day on which virus was detected in serum was day 11. The animal the died was the one with the longest vaccine-to-challenge interval. Survival diminished as the vaccine-to-challenge interval increased. A trend towards increasing duration of viremia was also observed with increased intervals between vaccination and challenge (Fisher-Hoch et al., 2000).
7. V-LSG + V-LSN
a. Vaccine Ontology ID:
VO_0004082
b. Type:
Vaccina virus
c. Preparation
Each sequence is derived from the Josiah strain of Lassa virus, isolated from a patient in Sierra Leone (Fisher-Hoch et al., 2000).
d. Virulence
e. Description
V-LSG is a vaccinia viruses expressing the S-segment Lassa glycoprotein and V-LSN is a vaccinia viruses expressing the S-segment Lassa nucleoprotein. V-LSG + V-LSN is a vaccine that includes injections of each V-LSG and V-LSN separately (Fisher-Hoch et al., 2000).
f. Monkey Response
  • Host Strain: Rhesus and Cynomolgus
  • Vaccination Protocol: All animals received a single vaccination consisting of 0.2 ml of vaccine given intradermally and simultaneously at four separate sites (each forearm and the lateral aspect of each thigh) at a dilution which delivered to each animal a total dose of 109 PFU. All animals were challenged subcutaneously with 103 to 104 PFU of the Josiah strain of Lassa virus in 0.5 ml of phosphate-buffered saline within 36 to 700 days (Fisher-Hoch et al., 2000).
  • Persistence: The latest day on which virus could be recovered from serum was day 14, and that from tissues was day 21. Evidence for persistence elsewhere in tissues or fluids in survivors could not be found by cocultivation of tissues taken up to 112 days following challenge. However, autopsy and biopsy material examined by RT-PCR revealed that viral RNA could be detected at least 112 days after challenge (Fisher-Hoch et al., 2000).
  • Side Effects: None noted
  • Efficacy: When used together, V-LSG and V-LSN can provide sufficient means for protection against Lassa fever (Fisher-Hoch et al., 2000).
  • Description: 5 out of 6 of the monkeys survived. This protection against death was significant when compared with the death rate of the controls. These animals showed significantly diminished mean virus titers compared with those of unvaccinated animals. The animal the died was the one with the longest vaccine-to-challenge interval. Survival diminished as the vaccine-to-challenge interval increased. A trend towards increasing duration of viremia was also observed with increased intervals between vaccination and challenge (Fisher-Hoch et al., 2000).
8. V-LSG/N
a. Vaccine Ontology ID:
VO_0004083
b. Type:
Vaccina virus
c. Preparation
V-LSG is a vaccinia viruses expressing the S-segment Lassa glycoprotein (Fisher-Hoch et al., 2000).
d. Virulence
e. Description
V-LSG/N is a vaccinia viruses expressing the full length glycoprotein and nucleoprotein in the same construct (Fisher-Hoch et al., 2000).
f. Monkey Response
  • Host Strain: Rhesus
  • Vaccination Protocol: Two animals were vaccinated. Each animal received a single vaccination consisting of 0.2 ml of vaccine given intradermally and simultaneously at four separate sites (each forearm and the lateral aspect of each thigh) at a dilution which delivered to each animal a total dose of 109 PFU. All animals were challenged subcutaneously with 103 to 104 PFU of the Josiah strain of Lassa virus in 0.5 ml of phosphate-buffered saline within 36 to 700 days
  • Persistence: The latest day on which virus could be recovered from serum was day 14, and that from tissues was day 21. Evidence for persistence elsewhere in tissues or fluids in survivors could not be found by cocultivation of tissues taken up to 112 days following challenge. However, autopsy and biopsy material examined by RT-PCR revealed that viral RNA could be detected at least 112 days after challenge (Fisher-Hoch et al., 2000).
  • Side Effects: None noted
  • Efficacy: The results of this experiment show that V-LSG/N provides effective means of protecting monkeys against the Lassa virus (Fisher-Hoch et al., 2000).
  • Description: Both of the animals survived when challenged with the Lassa virus. These animals showed no significant mean virus titers when compared with those of unvaccinated animals (Fisher-Hoch et al., 2000).
9. V-LSG1 + V- LSG2
a. Vaccine Ontology ID:
VO_0004081
b. Type:
Vaccina virus
c. Preparation
The sequence is derived from the Josiah strain of Lassa virus, isolated from a patient in Sierra Leone (Fisher-Hoch et al., 2000).
d. Virulence
e. Description
V-LSG1 + V- LSG2 is a vaccinia viruses expressing the S-segment Lassa single glycoproteins V-LSG1 [containing residues 1 to 296] and V-LSG2 [with a deletion of residues 67 to 234] (Fisher-Hoch et al., 2000).
f. Monkey Response
  • Host Strain: Rhesus
  • Vaccination Protocol: All animals received a single vaccination consisting of 0.2 ml of vaccine given intradermally and simultaneously at four separate sites (each forearm and the lateral aspect of each thigh) at a dilution which delivered to each animal a total dose of 109 PFU. Each vaccine was administered in one arm and one leg on the ipsilateral side. All animals were challenged subcutaneously with 103 to 104 PFU of the Josiah strain of Lassa virus in 0.5 ml of phosphate-buffered saline within 36 to 700 days (Fisher-Hoch et al., 2000).
  • Persistence: The latest day on which virus could be recovered from serum was day 14, and that from tissues was day 21. Evidence for persistence elsewhere in tissues or fluids in survivors could not be found by cocultivation of tissues taken up to 112 days following challenge. However, autopsy and biopsy material examined by RT-PCR revealed that viral RNA could be detected at least 112 days after challenge (Fisher-Hoch et al., 2000).
  • Side Effects: None noted
  • Efficacy: Although V-LSG1 and V-LSG2 do not provide sufficient protection by themselves, when used together the can provide protective immunity to primates. This means that both glycoproteins are independently important in Lassa virus protection (Fisher-Hoch et al., 2000).
  • Description: Both of the monkeys vaccinated with V-LSG1 + V-LSG2 were protected when challenged Lassa virus (Fisher-Hoch et al., 2000).
10. V-LSGPC
a. Vaccine Ontology ID:
VO_0004086
b. Type:
Vaccina virus
c. Gene Engineering of LASVsSgp2 glycoprotein
  • Type: Protein
  • Description:
  • Detailed Gene Information: Click here.
d. Preparation
The Lassa virus GPC gene was assembled and ligated into the unique SmaI site of the vaccinia virus expression vector pSCl1. The products of this reaction were transfected into competent Escherichia coli MC1061 cells, and a transformant containing the proper orientation of the Lassa GPC gene was identified by restriction enzyme digestion of plasmid DNA and confirmed by nucleotide sequence analysis (Auperin et al., 1988).
e. Description
V-LSGPC is a cloned cDNA containing the complete glycoprotein gene of the Josiah strain of Lassa virus was inserted into the thymidine kinase (TK) gene of the New York Board of Health (WYETH) strain of vaccinia virus (Auperin et al., 1988).
f. Guinea pig Response
  • Host Strain: Hartley
  • Vaccination Protocol: Animals were vaccinated with l0^8 plaque-forming units (PFUs) of V-LSGPC recombinant virus using a single intradermal injection of 0.1 ml on the back. l04 PFUs of guinea of pig-cultured Lassa virus were given by intraperitoneal innoculation 21 days post-vaccination.
  • Persistence: All surviving animals were completely free of virus in their blood and tissues by 61 days postchallenge, when the experiment was terminated (Auperin et al., 1988).
  • Side Effects: Two to three days after vaccination, vesicles developed at the site of inoculation on each animal. The vesicles arising from V-LSGPC were approximately 2-3 mm. All vesicles scabbed and completely healed by 19 days postvaccination. vaccinated animals developed mild symptoms of Lassa fever following challenge. The animals vaccinated with V-LSGPC virus developed low-grade fevers, which began about 8 days post-challenge and lasted approximately 4 days. The unprotected animals, however, developed significantly higher fevers, which persisted until
    they died (Auperin et al., 1988).
  • Efficacy: Vaccination with V-LSGPC effectively limited the replication of Lassa virus in comparison to the unvaccinated animals. The ability to construct recombinant vaccinia viruses that express heterologous genes offers great potential for vaccine development (Auperin et al., 1988).
  • Description: 21 days post vaccination the animals were challenged with Lassa virus. All animals that received V-LSGPC recombinant virus survived the lethal Lassa virus challenge (Auperin et al., 1988).
11. V-LSN
a. Vaccine Ontology ID:
VO_0004079
b. Type:
Vaccina virus
c. Preparation
The sequence is derived from the Josiah strain of Lassa virus, isolated from a patient in Sierra Leone (Fisher-Hoch et al., 2000).
d. Virulence
e. Description
V-LSN is a vaccinia viruses expressing the S-segment Lassa nucleoprotein (Fisher-Hoch et al., 2000).
f. Monkey Response
  • Host Strain: Rhesus and Cynomolgus
  • Vaccination Protocol: All animals received a single vaccination consisting of 0.2 ml of vaccine given intradermally and simultaneously at four separate sites (each forearm and the lateral aspect of each thigh) at a dilution which delivered to each animal a total dose of 109 PFU. All animals were challenged subcutaneously with 103 to 104 PFU of the Josiah strain of Lassa virus in 0.5 ml of phosphate-buffered saline within 36 to 700 days (Fisher-Hoch et al., 2000).
  • Persistence: The latest day on which virus could be recovered from serum was day 14, and that from tissues was day 21. Evidence for persistence elsewhere in tissues or fluids in survivors could not be found by cocultivation of tissues taken up to 112 days following challenge. However, autopsy and biopsy material examined by RT-PCR revealed that viral RNA could be detected at least 112 days after challenge (Fisher-Hoch et al., 2000).
  • Side Effects: Monkeys had marked lymphopenia and higher mean aspartate aminotransferase values than unvaccinated animals. The V-LSN-vaccinated animals were observed to be sicker and died earlier than unvaccinated animals (Fisher-Hoch et al., 2000).
  • Efficacy: Vaccination using the nucleoprotein may protect primates against a lower challenge dose of Lassa virus, however, the V-LSN vaccine was not significantly protective (Fisher-Hoch et al., 2000).
  • Description: 8 of the 11 vaccinated animals died, which shows that this vaccine was not significantly protective. The V-LSN animals appeared to have a shorter and more acute process than unprotected animals. The median day of death for V-LSN animals was day 11.5, compared with day 13 for the control animals. This phenomenon was related to the challenge dose. Back titration of the challenge inoculum used in the final experiment showed that the titer had dropped from 104 to 103 PFU/ml. The three V-LSN-vaccinated animals in that experiment that received the lower challenge titer survived. These three animals were rhesus monkeys (Fisher-Hoch et al., 2000).
12. VSV[Delta]G/LVGPC
a. Vaccine Ontology ID:
VO_0004087
b. Type:
Live Attenuated
c. Gene Engineering of LASVsSgp2 glycoprotein
  • Type: Protein
  • Description:
  • Detailed Gene Information: Click here.
d. Preparation
The recombinant VSV expressing the glycoprotein of Lassa virus, strain Josiah, and Zaire ebolavirus (ZEBOV), strain Mayinga, were generated using the infectious clone for the VSV, Indiana serotype. Briefly, the appropriate open reading frames for the glycoproteins were generated by PCR, cloned into the VSV genomic vectors lacking the VSV glycoprotein gene, sequenced-confirmed, and rescued. The recombinant viruses expressing Lassa virus glycoprotein and ZEBOV glycoprotein were designated VSV[Delta]G/LVGPC (Figure 1A) and VSV[Delta]G/ZEBOVGP, respectively (Geisbert et al., 2005).
e. Virulence
f. Description
VSV[Delta]G/LVGPC ia a live attenuated recombinant vesicular stomatitis virus expressing the GPC of Lassa virus, strain Josiah. Vaccines based on live attenuated rVSV have been highly effective in animal models and are particularly attractive because they can be administered by the mucosal route (Geisbert et al., 2005).
g. Monkey Response
  • Host Strain: Cynomolgus macaques
  • Vaccination Protocol: Four cynomolgus macaques, 4–6 y old and weighing between 3 kg and 8 kg, were vaccinated intramuscularly with approximately 2 × 107 PFU of VSV[Delta]G/LVGPC, and two with an equivalent dose of VSV[Delta]G/ZEBOGP (controls). The six cynomolgus macaques were challenged intramuscularly 28 d after the single-dose immunization with 1 × 104 plaque-forming units of Lassa virus, Josiah strain (Geisbert et al., 2005).
  • Persistence: None noted
  • Side Effects: After vaccination, none of the nonhuman primates displayed any signs of clinical symptoms, indicating that the rVSVs were apathogenic for these animals (Geisbert et al., 2005).
  • Efficacy: The VSV-based vector expressing the Lassa virus GPC mediated complete protection of four of four cynomolgus monkeys from a high-dose lethal challenge of Lassa virus. Protection was associated with the generation of Lassa-specific CD8+ T cell and antibody responses. The primary concern regarding use of the rVSV vaccine platform in humans is related to the fact that this is a replication-competent vaccine, and thus demonstration of safety is of paramount importance (Geisbert et al., 2005).
  • Description: After the challenge, the two control animals started to show clinical signs of illness on day 3, when one of the animals had a fever. By day 10, both control animals developed macular rashes and anorexia, and one animal had severe facial edema, which is prognostic for a poor outcome in humans. These control animals succumbed to the Lassa virus challenge and were euthanized on day 11 and day 13. At necropsy, both controls showed lesions and pathological changes consistent with Lassa fever in nonhuman primates. In contrast, none of the vaccinated animals became sick, and all four animals were fully protected against the high Lassa challenge dose. By day 7 after challenge, all six monkeys were viremic. However by day 10, all four of the vaccinated animals had cleared the viremia, while both control animals had high viremias, which was maintained until euthanasia (Geisbert et al., 2005).
13. YFV17D/LAS-GPC
a. Vaccine Ontology ID:
VO_0004088
b. Type:
Live Attenuated
c. Preparation
The YFV17D/LASV-GPC plasmid is constructed in the background of the full-length YFV17D cDNA clone by fusion PCR mutagenesis. The LASV-GPC gene of the AV strain is amplified by RT/PCR and cloned into pcDNA. The nucleotide sequences of PCR-derived DNA fragments and gene fusions are confirmed by sequencing. The recombinant YFV17D/LASV-GPC plasmid is linearized by XhoI and used for in vitro RNA transcription (Bredenbeek et al., 2006).
d. Virulence
e. Description
YFV17D/LAS-GPC is a Yellow Fever Vaccine 17D (YFV17D) that has been used as a vector for the Lassa virus glycoprotein precursor (LASV-GPC) resulting in construction of YFV17D/LASV-GPC recombinant virus. The virus is replication-competent and processes the LASV-GPC in cell cultures (Bredenbeek et al., 2006).
f. Guinea pig Response
  • Host Strain: 13
  • Vaccination Protocol: Sixteen outbred guinea pigs were subcutaneously inoculated with 1 × 105 PFU/0.5 ml of the recombinant YFV17D/LASV-GPC virus and two animals were sacrificed at days 0, 4, 7, 10 and 14 to track the virus distribution in blood and tissues. At day 14, six animals were boosted with the same dose of the recombinant virus and plasma samples were collected on days 8, 15 and 24 after to measure antibody responses against YFV17D and LASV-GPC in IgG ELISA. Antigens were prepared from serum-free virus stocks of YFV17D and MOP/LAS (Lukashevich et al., 2005) by ultracentrifugation on sucrose cushion. Concentrated viruses were suspended in carbonate–bicarbonate buffer, briefly sonicated and used to cover wells of microtitration plates overnight at 4 °C. After blocking, 1:100 dilutions of guinea pig sera were added and incubated for 2 h at room temperature. Challenge experiments were preformed (Bredenbeek et al., 2006).
  • Persistence: None noted
  • Side Effects: None noted
  • Efficacy: 80% of animals were protected against the fatal challenge. This study demonstrates the potential to develop an YFV17D-based bivalent vaccine against Lassa Virus (Bredenbeek et al., 2006).
  • Description: 80% of animals were protected against the fatal challenge. Incomplete protection could be explained by differences in vaccine formulation (GPC + NP vs. GPC) and by GPC sequence differences between AV and Josiah strains of LASV. Blood and tissue samples were collected from vaccinated animals at different time points for hematology, blood chemistry, RNA extraction, plaque assay, virus isolation and ELISA. As expected, the inoculated animals had no clinical manifestations and all standard measurable blood and chemistry parameters were in normal ranges. In plasma, the recombinant virus was not detectable by plaque assay or by biological amplification. Recombinant viral RNA was not detectable by RT/PCR in 140 μl of plasma extracted on days 4, 10, and 21. However, when RNA samples were prepared from 0.5 ml of total blood, an RT/PCR assay gave a strong positive signal on day 4 after YFV17D/ LAS-GPC inoculation. Still, blood samples collected on day 10 and 21 were PCR negative. Viral RNA sequences were only transiently detectable on days 7–14 in spleen and liver. Nucleotide sequence analysis of PCR products confirmed their derivation from YFV17D/LAS-GPC. Taken together, these data confirm that recombinant YF17D/LAS-GPC replicated poorly in tissues of vaccinated guinea pigs. Interestingly, in clinical trials in individuals vaccinated with chimeric YFV17D-based vaccines, viremia levels were even lower than the levels of YFV17D determined to be safe. This suggests that insertion of a foreign gene can affect in vivo viral replication and make recombinant YFV17D-based vaccines even safer than the parental vaccine, YFV17D (Bredenbeek et al., 2006).
IV. References
1. Auperin et al., 1988: Auperin DD, Esposito JJ, Lange JV, Bauer SP, Knight J, Sasso DR, McCormick JB. Construction of a recombinant vaccinia virus expressing the Lassa virus glycoprotein gene and protection of guinea pigs from a lethal Lassa virus infection. Virus research. 1988 Feb; 9(2-3); 233-48. [PubMed: 3354260].
2. Botten et al., 2006: Botten J, Alexander J, Pasquetto V, Sidney J, Barrowman P, Ting J, Peters B, Southwood S, Stewart B, Rodriguez-Carreno MP, Mothe B, Whitton JL, Sette A, Buchmeier MJ. Identification of protective Lassa virus epitopes that are restricted by HLA-A2. Journal of virology. 2006 Sep; 80(17); 8351-61. [PubMed: 16912286].
3. Bredenbeek et al., 2006: Bredenbeek PJ, Molenkamp R, Spaan WJ, Deubel V, Marianneau P, Salvato MS, Moshkoff D, Zapata J, Tikhonov I, Patterson J, Carrion R, Ticer A, Brasky K, Lukashevich IS. A recombinant Yellow Fever 17D vaccine expressing Lassa virus glycoproteins. Virology. 2006 Feb 20; 345(2); 299-304. [PubMed: 16412488].
4. Fisher-Hoch et al., 2000: Fisher-Hoch SP, Hutwagner L, Brown B, McCormick JB. Effective vaccine for lassa fever. Journal of virology. 2000 Aug; 74(15); 6777-83. [PubMed: 10888616].
5. Fisher-Hoch et al., 2001: Fisher-Hoch SP, McCormick JB. Towards a human Lassa fever vaccine. Reviews in medical virology. 2001 Sep-Oct; 11(5); 331-41. [PubMed: 11590670].
6. Geisbert et al., 2005: Geisbert TW, Jones S, Fritz EA, Shurtleff AC, Geisbert JB, Liebscher R, Grolla A, Stroher U, Fernando L, Daddario KM, Guttieri MC, Mothe BR, Larsen T, Hensley LE, Jahrling PB, Feldmann H. Development of a new vaccine for the prevention of Lassa fever. PLoS medicine. 2005 Jun; 2(6); e183. [PubMed: 15971954].
7. Lukashevich et al., 2005: Lukashevich IS, Patterson J, Carrion R, Moshkoff D, Ticer A, Zapata J, Brasky K, Geiger R, Hubbard GB, Bryant J, Salvato MS. A live attenuated vaccine for Lassa fever made by reassortment of Lassa and Mopeia viruses. Journal of virology. 2005 Nov; 79(22); 13934-42. [PubMed: 16254329].
8. Morrison et al., 1989: Morrison HG, Bauer SP, Lange JV, Esposito JJ, McCormick JB, Auperin DD. Protection of guinea pigs from Lassa fever by vaccinia virus recombinants expressing the nucleoprotein or the envelope glycoproteins of Lassa virus. Virology. 1989; 171(1); 179-188. [PubMed: 2741340].