[False-positive reactions in laboratory diagnosis of Lassa, Marburg, and Ebola viral hemorrhagic fevers and AIDS]. / Lozhnopolozhitel'nye reaktsii pri laboratornoi diagnostike virusnykh gemorragicheskikh likhoradok Lassa, Marburg, Ebola i SPIDa.

Sera of normal subjects and AIDS patients living in Minsk and Odessa were tested for antibodies to hazardous viral infections Lassa, Marburg, and Ebola. Four to 16% of examinees were seropositive to Ebola virus, 0.8 to 2.3% to Lassa, and up to 0.8% to Marburg virus. Common B-epitopes were found in viruses belonging to different families: Lassa, Ebola, and HIV. Antibodies specific to these viruses antigens were found in the reference sera to influenza A and B, respiratory syncytial virus, and adenovirus. Sera of convalescents after malaria and of AIDS patients contained antibodies to Lassa virus.

[The dynamics of the formation of IgG subclasses in Balb/c and CBA mice infected with the LCM, Lassa and Mopeia viruses and their role in diagnosis]. / Dinamika obazovaniia podklassov IgG u myshei Balb/c i CBA pri zarazhenii virusami LKhM, Lassa, Mopeiia i ikh rol' v diagnostike.

The dynamics of the induction of individual IgG subclasses in BALB/c and CBA mice and their role on the diagnostics of arenaviruses LCM, Lassa and Mopeia was studied. The study demonstrated that in solid-phase enzyme immunoassay (EIA) isotypes IgG2a and IgG2b to virus Mopeia could be used for the differentiation of virus Mopeia from viruses LCM and Lassa, and the antigen of virus Mopeia could be used for the preparation of diagnostic EIA systems not only to nonpathogenic virus Mopeia, but also to pathogenic viruses LCM and Lassa.

[The production of antibody-producing hybridomas to the Lassa virus]. / Poluchenie antiteloprodutsiruiushchikh gibridom k virusu Lassa.

The work deals with obtaining hybrid cell lines producing monoclonal antibodies to Lassa arenavirus. To obtain preparations for the screening of hybridomas by indirect immunofluorescence techniques, the dynamics of the accumulation of Lassa virus antigen in cell cultures Vero and 4647 was studied. The maximum accumulation of the virus antigen in Vero cells was shown to occur on day 3 after inoculation with a dose of 1.0 PFU/ml. The influence of different doses of gamma radiation on the infectious and antigenic activity of the virus was studied. The expediency of using a dose of 20.0 kGy for the irradiation of the virus was shown. The optimum schedule for the immunization of BALB/c mice was worked out, which made it possible to obtain activated mouse spleen cells used for the construction of hybridomas. The capacity of hybrid cells, injected into syngeneic mice, for the generation of tumors was shown.

[Production of infectious virus and the accumulation in Vero cells of Pichinde virus antigens detectable by an indirect fluorescent antibody method]. / Produktsiia infektsionnogo virusa i nakoplenie v kletkakh Vero antigenov virusa Pichinda, vyiavliaemykh nepriamym metodom fliuorestsiruiushchikh antitel.

The dynamics of accumulation of infectious Pichinde virus in the culture medium and virus-specific antigens in cells was studied in relation to multiplicity of infection in a multicycle experiment. Differences in the fluorescence pattern of Pichinde virus antigens in IFAT were found to depend on the use of acetone or formaldehyde for fixation of the infected cells.