Physical, chemical and serological properties of C-type virus associated with transplantable rat Thurzo-Svee leukemia.

Cells of rat Thurzo-Svee leukemia produce C-type virus. Viral particles are shown to contain high-molecular weight RNA and RNA-dependent DNA polymerase the virus possesses mammalian gs-3 antigen and rat species-specific gs-1 antigen and thus appears to be of rat origin.

Effect of influenza virus on the immune responsiveness of animals.

Infection of mice with A/Hong Kong/1/68 (H3N2) and A/PR8/34 (H0N1) influenza virus strains resulted in a significant inhibition of the formation of antibody-producing cells in response to administration of sheep erythrocytes and a reduced capacity of spleen cells to induce "graft-versus-host" reaction. The immunosuppression caused by influenza infection was observed for a long period of time post infection (3--6 months). The extent of inhibition of antibody production depended on the dose of virus, route of inoculation, the sequence of infection and immunization and the internal between them. Heat-inactivated virus exerted no immunosuppressive effect.

[Radiation protective effect of low molecular weight thymus preparations]. / Protivoluchevoe deistvie nizkomolekuliarnykh preparatov vilochkovoi zhelezy.

The antiradiation efficiency of low molecular thymic preparations (vilosen, thymogen) was determined. The therapeutic activity of thymic preparations is due to their influence on basic radiation injury syndromes (hemopoietic, gastrointestinal, immunodepressive). The protective mechanisms and perspectives of thymic preparations using in pathogenic therapy of radiation diseases are discussed.

[Changes in the functional activity of T- and B-lymphocytes in experimental infection due to different strains of the influenza virus]. / Izmenenie funktsional'noi aktivnosti T- i B-limfotsitov pri éksperimental'noi infektsii, vyzvannoi razlichnymi shtammami virusa grippa.

In mice infected with influenza A2/Port Chalmers and B/Hong Kong viruses the formation of antibody-producing cells (APC) to the thymus-dependent antigen, sheep red blood cells (SRBC) was found to be inhibited much stronger than that to the thymus-independent antigen (polyvinylpyrrolidone K-90). Influenza A/PR-8/34 virus was approximately similarly active in both systems. Spleen cells of mouse donors infected with influenza virus were characterized by a markedly reduced capacity to form APC to ARBC when inoculated into irradiated recipients. This capacity was recovered if the donor spleen cells of infected animals were inoculated into recipients in mixture with T-lymphocytes of intact animals. Possible mechanisms of lymphocyte damage in influenza infection are discussed.

[The immunocorrective effect of laser reflexotherapy in experimental influenza infection]. / Immunokorrigiruiushchii éffekt lazernoi refleksoterapii pri éksperimental'noi grippoznoi infektsii.

The influence of two schemes of laser acupuncture on some cell-mediated and humoral immunity characteristics of mice, as well as on their nonspecific antiviral resistance, in acute experimental influenza infection has been studied. The use of both schemes has been found to considerably decrease the severity of infection, enhancing the activity of lymphocytes of infected mice in the graft versus host reaction, the O2-producing activity of alveolar macrophages and modulating the ratio of antihemagglutinins and nonspecific antiviral inhibitors in the blood serum.

[Role of immune cytolysis and its thymosin stimulation in experimental influenza]. / Rol' immunnogo tsitoliza i ego stimuliatsii timozinom v techenii éksperimental'noi infektsii.

In experiments on C57BL and CC57W mice the acute or chronic course of experimental influenza infection has been shown to correlate with the activity of immune cytolysis. At a low level of the cytolytic activity of T-lymphocytes the prolonged persistence of influenza virus develops. The stimulation of cell-mediated immunity with thymosin prevents the development of chronic influenza infection.

[The antitumor activity of vaccines obtained by using a culture broth filtrate of Bac. mesentericus AB-56 or antibiotic AB-56]. / Protypukhlynna aktyvnist' vaktsyn, oderzhanykh za dopomohoiu fil'tratu kul'tural'noï ridyny Bac. mesentericus AB-50 abo antybiotyka AB-56.

The possibility of the purified antibiotic, extracted from the Bac. mesentericus AB-56 culture liquid, application for the antitumoral vaccine preparation and standardization was established in experiment, conducted on the mice of Balb/c line.

Tumor cell heterogeneity.

The paper deals with the analysis of literary data on the tumor cell heterogeneity. Phenotypic, genetic and epigenetic mechanisms of heterogeneity are considered. The heterogeneity of metastasis is considered too. The importance for the biology of populations of tumor cells and the sensitivity of tumors to therapeutic treatment are discussed.

[Dependence of the cocarcinogenic action of the influenza virus on the nature of the influenza infection]. / Zavisimosti kokantserogennogo deistviia virusa grippa ot kharaktera grippoznoi infektsii.

It was shown in experiments of CC57W mice that cocarcinogenic activity of influenza A/PR8/34 virus correlates with acute or chronic pattern of infection. Prolonged persistence of the virus resulted in significant stimulation of the lung tumor incidence in infected mice. The prevention with thymosin of chronic influenza infection development in CC57W mice lead to a decrease in the incidence of lung tumors to the control level.

[The biological effects in animals in relation to the accident at the Chernobyl Atomic Electric Power Station. 9. The morphofunctional indices of the immunocompetent organs in mice]. / Biologicheskie éffekty u zhivotnykh v sviazi s avariei na Chernobyl'skoi AES. Soobshchenie 9. Morfofunktsional'nye pokazateli nekotorykh immunokompetentnykh organov myshei.

The permanent action of small doses of low-intensity radiation on the immune status of 2.5-3.5 month CC57W mice has been investigated. Total doses of internal and external irradiation were about few cGy. The permanent action of low-level radiation on the experimental animals of the first and fourth generations was shown to change spleen and lymph nodes weights and the count of lymphocytes isolated from these organs. Cellularity and DNA synthesis in the lymph-node lymphocytes and their proliferative response to polyclonal mitogens also changed. The alterations in the parameters that characterized T-lymphocyte population were statistically significant.

[The biological effects in animals in relation to the accident at the Chernobyl Atomic Electric Power Station. 10. Cooperative immune reactions in different generations of mice]. / Biologicheskie éffekty u zhivotnykh v sviazi s avariei na Chernobyl'skoi AES. Soobshchenie 10. Kooperativnye immunnye reaktsii u razlichnykh pokolenii myshei.

The immune status of mice has been assessed by the whole complex of data. The permanent action of low-level radiation has been shown to suppress considerably the rate of reactions of the delayed-type hypersensitivity and "graft versus host" disease, as well as NK and specific cytolytic T-lymphocyte activity. The dynamics of accumulation and the levels of antiviral antibodies in the serum, lung and trachea extracts are virtually invariable. The resistance of experimental animals to influenza is lower than that of non-irradiated mice of the same line and age. The data obtained indicate that the immune disturbances revealed are connected not only with the alteration of lymphoid cell populations, but also with the alteration of the immune regulation mechanisms.