| baculovirus expression of the glycoprotein gene of lassa virus and characterization of the recombinant protein. | a recombinant baculovirus was constructed that expresses the glycoprotein gene of lassa virus (josiah strain) under the transcriptional control of the polyhedrin promoter. the expressed protein (b-lsgpc) comigrated with the authentic viral glycoprotein as observed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (sds-page), was reactive with monoclonal antibodies (mabs) in western blots, and was glycosylated. although the recombinant protein was not processed into the mature glycopro ... | 1992 | 1413995 |
| simultaneous expression of the lassa virus n and gpc genes from a single recombinant vaccinia virus. | a new transfer vector was constructed that directs the insertion of two heterologous genes into the vaccinia virus thymidine kinase (tk) gene during a single recombination event. this vector, pdavac2, contains bidirectional vaccinia p7.5 early/late promoter elements and two unique cloning sites. cdna clones containing the complete coding sequences for the lassa virus (josiah strain) nucleoprotein (n) and glycoprotein (gpc) genes were inserted into the vaccinia tk gene using this transfer vector. ... | 1991 | 2042398 |
| detection of lassa virus rna in specimens from patients with lassa fever by using the polymerase chain reaction. | suitable oligonucleotide primers and probes were synthesized to amplify lassa virus (josiah strain)-specific nucleoprotein and glycoprotein gene fragments by using reverse transcription combined with the polymerase chain reaction (pcr). our primers did not amplify the related lymphocytic choriomeningitis virus. by using pcr, about 50 50% tissue culture infective doses could be detected in the supernatant of infected cells. furthermore, in all five serum specimens and four of five urine specimens ... | 1990 | 2279999 |
| protection of guinea pigs from lassa fever by vaccinia virus recombinants expressing the nucleoprotein or the envelope glycoproteins of lassa virus. | a recombinant vaccinia virus that expresses the nucleoprotein gene of lassa virus (josiah strain) under the control of the p7.5 promoter was constructed using the lacz coexpression transfer vector psc11. southern blot analysis demonstrated that recombination of the sequences inserted within the thymidine kinase gene of the transfer vector into the hindiii j fragment of vaccina virus genomic dna occurred properly. a 63-kda protein identical in electrophoretic mobility to authentic lassa nucleopro ... | 1989 | 2741340 |
| nucleotide sequence of the lassa virus (josiah strain) s genome rna and amino acid sequence comparison of the n and gpc proteins to other arenaviruses. | the complete nucleotide sequence of the s genome rna of the josiah strain of lassa virus was determined from cloned cdna. the s rna is 3402 nucleotides long with a calculated molecular weight of 1.09 x 10(6) da. the nucleotide base composition is 26.84% adenine, 21.40% guanine, 22.75% cytosine, and 29.01% uridine. the 5' and 3' terminal nucleotide sequences are conserved and complimentary for 19 nucleotides, the nucleoprotein and glycoprotein genes are arranged in ambisense coding strategy, and ... | 1989 | 2916333 |
| kinetic study of platelets and fibrinogen in lassa virus-infected monkeys and early pathologic events in mopeia virus-infected monkeys. | the rhesus monkey, an established model of lassa fever, was used to study hematologic and hemostatic aspects of lassa fever and whether mopeia (also known as mozambique) virus induces any cellular damage in this model. six days after subcutaneous injection of 10(3.48) plaque forming units (pfu) of lassa virus (josiah strain) one group of monkeys received an intravenous injection of 111in-labeled allogeneic platelets and another group received 125i-labeled alogeneic fibrinogen. lassa virus-infect ... | 1985 | 4037187 |
| pathogenesis of lassa virus infection in guinea pigs. | a rodent model for human lassa fever was developed which uses inbred (strain 13) and outbred (hartley) guinea pigs. strain 13 guinea pigs were uniformly susceptible to lethal infection by 2 or more pfu of lassa virus strain josiah. in contrast, no more than 30% of the hartley guinea pigs died regardless of the virus dose. in lethally infected strain 13 guinea pigs, peak titers of virus (10(7) to 10(8) pfu) occurred in the spleen and lymph nodes at 8 to 9 days, in the salivary glands at 11 days, ... | 1982 | 6749685 |
| lassa virus infection of rhesus monkeys: pathogenesis and treatment with ribavirin. | rhesus monkeys were experimentally infected with lassa virus to establish their suitability as a nonhuman primate model for the human disease and to test the protective efficacy of ribavirin, an antiviral drug. six of 10 untreated control monkeys died after subcutaneous inoculation of 10(6.1) plaque-forming units of lassa virus (strain josiah). infectivity titrations of tissue homogenates from the six dead monkeys indicated significant replication in all tissues tested except the central nervous ... | 1980 | 6768812 |
| experimental study on the possibility of treatment of some hemorrhagic fevers. | after intracerebral challenge with 100 pfu of lassa virus (strain josiah), all infected mice (cba/calac) died (control group). production of pro-inflammatory cytokines (il-1beta, tnf-alpha) significantly increased in the blood of these mice during the infection. for neutralization of increasing concentrations of these cytokines recombinant il-1ra was used intraperitonealy at a dose 100 microg kg(-1), everyday, within 5 days from the third day after the challenge. injections of il-1ra decreased t ... | 2000 | 11000462 |
| [immunogenic and protective characteristics of recombinant lassa virus np protein]. | recombinant fragment of lassa virus (strain josiah) nucleocapsid protein (corresponding to amino acid residues 141 + 569) constructed by dr. jan ter meulen (tropenmedizine, hamburg) was used for immunizing cba/calac mice. the preparation was injected intraperitoneally twice with 2-week interval in a dose of 10 micrograms. the parameters of the resultant specific humoral and cell-mediated immunity were comparable to those in reference animals immunized with inactivated lassa virus. challenge with ... | 2002 | 12046464 |
| lassa virus infection in experimentally infected marmosets: liver pathology and immunophenotypic alterations in target tissues. | lassa virus causes thousands of deaths annually in western africa and is considered a potential biological weapon. in an attempt to develop a small nonhuman primate model of lassa fever, common marmosets were subcutaneously inoculated with lassa virus strain josiah. this inoculation resulted in a systemic disease with clinical and morphological features mirroring those in fatal human lassa infection: fever, weight loss, high viremia and viral rna load in tissues, elevated liver enzymes, and seve ... | 2007 | 17409137 |
| development and evaluation of a one-step quantitative rt-pcr assay for detection of lassa virus. | lassa fever is a severe viral hemorrhagic illness caused by lassa virus. based on estimates, the number of lasv infections ranges from 300,000 to 500,000 cases in endemic areas with a fatality rate of 1%. development of fast and sensitive tools for the control and prevention of lassa virus infection as well as for clinical diagnostics of lassa fever are crucial. here we reported development and evaluation of a one-step quantitative rt-qpcr assay for the lassa virus detection - lasv-fl. this assa ... | 2019 | 31170468 |
| a single-shot lassa vaccine induces long-term immunity and protects cynomolgus monkeys against heterologous strains. | a safe and protective lassa virus vaccine is crucially needed in western africa to stem the recurrent outbreaks of lassa virus infections in nigeria and the emergence of lassa virus in previously unaffected countries, such as benin and togo. major challenges in developing a lassa virus vaccine include the high diversity of circulating strains and their reemergence from 1 year to another. to address each of these challenges, we immunized cynomolgus monkeys with a measles virus vector expressing t ... | 2021 | 34108251 |