[Development and certification of libraries of the MDCK continuous cell line for production of influenza vaccine].

Seeding and working banks of the continuous MDCK cell culture suitable for the production of cultured influenza vaccine were created and deposited at liquid nitrogen temperature at the "Vector" State Research Center of Virology and Biotechnology. The MDCK cell culture was shown to have morphology typical of the discussed cell line; it does not have any alien agents and is oncogenically safe; its enzimogram and karyotype are typical of the donor line; finally, its biological properties are stable during a long period of cultivation and its sensitivity to influenza virus is high, therefore, it can be recommended for the production of influenza vaccine. The continuous MDCK cell line was certified at Tarasevich Committee and was recommended by the MIBP Committee, Russia's Health Ministry, for its use as a substrate in the production of diagnostic and preventive immunoglobulins.

[The use of Vero (B) cell line for medico-biological preparations].

A variant of Vero cell line has been obtained, adapted to the Russian Eagle's medium with 8% fetal calf serum. The variant is characterized by intensive cell proliferation, possesses a different content of chromosomes, contains no oncogens and contaminants, specifically, Mycoplasma. The strain was characterized and certified in accordance with the WHO requirements.

[DNA content in the Purkinje cells of the rat cerebellum spontaneously infected with Kilham virus].

The DNA content in the cerebellum Purkinje cells of rats naturally contaminated with the Kilham virus and in the animals, in which no infection was observed, was determined cytospectrophotometrically on the Feulgen-stained preparations. The incidence of the cells with hyperdiploid nuclei was shown to be equal in the groups compared. It was concluded that the nonmultiple increase of the DNA content in the Purkinje cells of rat cerebellum was apparently unrelated to the virus infection.

Morphological methods of Kilham virus detection.

Morphological investigations on organs from Kilham virus (KV)-infected Syrian hamsters revealed acute glomerulonephritis with a clear-cut haemorrhagic syndrome. No pathological changes were found in internal organs from KV-infected rats.

Development of sensitive methods for detection of latent Kilham virus infection of rats.

The developed system of procedures, including preliminary selection of rats according to the presence of 19 S antibody in the blood serum, and the use of the most sensitive methods has increased considerably the incidence of detection of Kilham virus (KV) in organs of latently infected rats. To isolate and establish KV strains from the organs of rats in which the specific antigen was detected by immunofluorescence, at least 5-9 passages in rat embryo cell cultures or in newborn Syrian hamsters were required.