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V Z Agrba

Publications and source records attributed to V Z Agrba.

At least 19 recordsLinked to original sources
PubMed2005

[Immune and interferon status of primates].

The authors of the article have first determined standards of interferon (IFN) status of healthy primates (M. mullatta) belonging to different age groups, such as serum IFN, spontaneous IFN production, IFN-a and IFN-y production. They showed that old healthy primates have low ability of IFN-a and IFN-y production and high serum IFN level. The parameters of IFN status were compared to the number of B- and T-lymphocytes and their subpopulations; qualitative evaluation of protective properties of young and old healthy primates' immunity was carried out.

Adult↗
PubMed2004

Immunophenotypical characteristics of permanent cultures of lymphoid cells from Papio hamadryas and Macaca arctoides.

Immunophenotypical characteristics of primate cells were studied by enzyme immunoassay and flow cytofluorometry using a panel of monoclonal antibodies to human B- and T-lymphocyte antigens. Specific features of immunophenotype of cultured cells were detected. Simian lymphoid cultures consist of a mixture of B- and T-cells with mosaic antigenic structure expressing markers of B and T cell specificity.

Animals↗
PubMed2003

No evidence for productive PERV infection of baboon cells in in vivo infection model.

OBJECTIVES: The discovery that pig endogenous retroviruses are infectious for human cells in vitro lead to vehement discussions about the possible risk of infection after clinical xenotransplantation. Since PERV transmission to non-human primate cells in vitro has been observed, similar to human cells, infection studies in non-human primates should represent the best model to analyze a potential PERV transmission after xenotransplantation. However, it is still open to discussion, whether non-human primate cells can be infected productively-similar to human cells- and whether those species are suitable to analyze PERV infection risks in vivo. METHODS: In vitro, only few cell types can be tested for susceptibility. We developed a pig to baboon cell transplantation model with special emphasis on B-cell effective immunosuppression, removal of anti Gal-alpha 1,3-Gal-antibodies, inhibition of the complement cascade and long term survival of transplanted cellular grafts. This model allows us to investigate in vivo, whether any baboon cell types may be permissive for productive PERV infection. The xenograft recipients were investigated for up to 535 days post transplantation. Gal-alpha 1,3-Gal-antibody and complement levels were monitored. Potential PERV transmission was analyzed, not only in PBMC, but in a variety of tissue samples as well as in serum and plasma samples by PCR, RT-PCR and by detection of RT-activity. Moreover, potential PERV specific immune responses were studied by a highly sensitive Western-Blot-assay. RESULTS: Despite several days of extremely low levels of Gal-alpha 1,3-Gal-antibody and complement, and despite of long term xenochimerism, no evidence for PERV infection was obtained in any of the tested tissues or in the tested serum samples. CONCLUSION: This study supplies further evidence for a low susceptibility of baboons towards productive PERV infection after xenotransplantation.

Animals↗
PubMed1999

[Cytogenic characteristics and virogenic status of lymphoid cells from malignant baboon lymphomas].

Four lymphoid cell cultures obtained from Papio hamadryads with malignant lymphomas were studied. The cultured cells produced two lymphotropic EBV-like herpes virus of Papio (HVP) and T-lymphotropic monkey retrovirus STLV-1 (HTLV-1 family) or HVP alone. More than 100 subcultured cell lines were shown to remain mixed B- and T-cellular, the levels of T cells of different subpopulations were 15-50%. Cytogenetic investigations showed that one of the 4 cultures was tumorogenic and the others were derived from the normal cells of monkeys with malignant lymphomas. It is suggested that the presence of a cultural virus (viruses) may affect the karyotypes of cells.

Animals↗
PubMed1995

[The drug prophylaxis of peptic ulcer exacerbations].

453 patients with ulcer located in the duodenal bulb and pyloric part of the stomach in the presence of Helicobacter pylori were examined before and followed up after hospital treatment of the ulcer. The authors findings support the importance of maintenance with current antisecretory drugs and on-demand therapy as well as of combined antibacterial therapy against Helicobacter pylori. Adequate chemotherapy in the ulcer exacerbation was able to reduce the number of recurrences and complications.

Adolescent↗
PubMed1994

[The cytogenetic characteristics of human B-lymphoblastoid cell lines].

Permanent suspension B-cell lines HSL-1, HSL-2, HSL-3, HSL-4, HSL-5, HSL-8, HSL-9 have been obtained spontaneously from lymphocytes and cells of hematopoietic tissues of patients with various forms of leukemia and tumours. All cell lines contained Epstein-Barr virus (EBV). At early stages of cultivation (6-39th passages) normal karyotypes were established for all the tested lines which testified their origin from normal B-lymphocytes. In the process of cultivation of HSL-1 cell line, which (up to the 63rd passage) contained primarily the normal karyotypes, a substitution for tetraploid ones (92, XX, YY) by the 132nd passage was established. In line HSL-4, a pathological clone of cells with structural chromosome rearrangements (46, XY, -2, -12, der (12) t (2; 12) (p12, p13); del2 (p12), was revealed at the 26th passage. During a prolonged cultivation (up to the 130th passage) this abnormal clone forced out completely the clone with normal karyotype. Substitution of normal clone cells by cells with pathological karyotypes may point to their selective advantage.

B-Lymphocytes↗
PubMed1994

[The cytogenetic characteristics of B-lymphoid lines from Papio hamadryas baboons and Macaca arctoides brown macaques].

A cytogenetic analysis of 9 permanent suspension cell lines was performed. Cell lines were obtained from Papio hamadryas and Macaca arctoides cells by different methods. Five cell lines originated from non-malignant parental cells. Lines SPG-5 and SPG-6 were analysed at early stages of cultivation, with normal karyotypes being identified. In cell lines PL-11, MAL-1 and MAL-4 pathological clones with structural and numerical chromosomal rearrangements appeared only following a long-term cultivation. This phenomenon may be due presumably to the influence of cultivation on karyotype variability. In cell line LUG-4 chromosome marker 17p+ was found at early stages of cultivation. In sublines E9-1, E1-1 and E5-1, established from line LUG-4 by cloning, 17p+ chromosomal marker was found persisting. The presence of the marker 17p+ in all the cells at early passages testifies that the cell material from Papio with lymphoma, which was used for this line, might have the same chromosomal damage in its initial karyotype.

Animals↗
PubMed1990

[Comparative analysis of genomes of oncogenic B-lymphotropic herpesviruses reproducing in cell lines obtained from different monkey species].

The aim of this work was to study genomes of B-lymphotropic oncogenic herpesviruses of Macaca arctoides (HVMA), Papio hamadryas (HVP) and Cercopithecus aethiops (HVGM). Blot-hybridization detected inter- and intraspecific genome heterogeneity of investigated viruses in restriction sites EcoR1, Pst1 and Hind111. Virus-specific sequences in two-cell lines obtained from HVMA-induced rabbit tumours can prove HVMA a role in malignant tumour induction in rabbits.

Animals↗
PubMed1990

[Analysis of B-lymphotropic oncogenic herpesvirus of Macaca arctoides].

Some physico-chemical and molecular-biological parameters of B-lymphotropic herpes virus of Macaca arctoides (HVMA) have been analyzed. The buoyant density of virions and nucleocapsids in a gradient of the percoll density is 1.10 and 1.14 g/ml, respectively, while that of DNA in CsCl gradient is 1.717 g/ml, which is typical for herpes viruses of primates. At the same time the homology of DNA HVMA with DNA EBV and DNA HVP is 30-45%. Differences in restrictions sites between DNA HVMA, DNA HVP and DNA EBV are determined. The intraspecific heterogeneity of HVMA strains has been detected according to restriction sites of DNA. The HVMA genome size is about 170 kb. The DNA HVMA is colinear to the EBV genome, which is also typical of B-lymphotropic herpes viruses of primates.

Animals↗
PubMed1989

[A method of determining Campylobacter pylori in the gastric mucosa in peptic ulcer and chronic gastritis].

An original method is described for the detection of Campylobacter pylori in gastric mucosa biopsy specimens in chronic gastritis and gastroduodenal ulcers. The method is based on the detection (by a special test) of extremely high urease activity of C. pylori. The method has been employed in examinations of 211 patients. The results and prospects for the use of this technique for the detection of C. pylori in patients with gastroduodenal diseases are discussed.

Campylobacter↗
PubMed1983

Functional complementation between Epstein-Barr virus and herpesvirus papio.

The possibility of complementation between herpesvirus papio (HVP) and Epstein-Barr virus (EBV) was investigated. Strain 594S-F9 of HVP, unlike strain P3HR-1 of EBV, is not capable of inducing virus antigen synthesis in the EBV genome-carrying, nonproducer lymphoma cell line Raji. The effects of dual infection with these viruses were studied. With untreated viruses, the percentage of cells positive for viral antigens was equal to or slightly less than that in cultures infected with P3HR-1 virus only. However, if UV-irradiated P3HR-1 virus was employed in the dual infection, the relative number of virus antigen-positive cells was enhanced over cultures infected with P3HR-1 virus alone. These results suggest functional complementation between EBV and HVP.

Animals↗