Nutrient medium from rice flour hydrolysate for cell culturing and evaluation of the sensitivity to influenza viruses.

The nutrient medium on the basis of enzymatic hydrolysate of rice flour was used for culturing of MDCK and Vero(B) cells. Culturing of the vaccine line Vero(B) in this medium was not accompanied by changes in proliferative activity and sensitivity to influenza viruses A(H1N1) and A(H3N2).

[The spectrum of vetebrates' cell lines sensitive to highly pathogenic influenza A/tern/SA/61 (H5N3) and A/duck/Novosibirsk/56/05 (H5N1) viruses].

The reproduction of highly pathogenic avian influenza (HPAI) A/tern/SA/61 H5N3 and A/ducklNovosibirsk/56/05 H5NI viruses was comparatively studied in 16 human and animal cell lines. The strain A/duck/Novosibirsk/56/05 was shown to have a wider range of hosts. The most sensitive transplanted cell lines were found to be feline fibroblasts (CC-81), primarily trypsin-treated cells of chick embryonic fibroblasts (CEF), the kidney of dogs (MDCK), pigs (SPEV), monkeys (Vero), the human conjunctiva (1-5C-4), and, to a lesser extent, the feline kidney (CRFK).

[The reproduction of reassortant influenza A and B viruses with a known genome composition in different cell systems].

Reproduction of parental strains and reassortants (with known genome composition) of influenza A and B viruses was studied in chick embryos (CE) and in different cell lines (SPEV, MDCK, BHK-21, M22, etc.). The results agree with the concept that the yield of influenza A virus in CE depends on its M-gene.

[The effect of different factors on the reproduction of influenza viruses and reassortants in cell cultures].

The influence of the maintenance medium, polyethylene glycol (PEG), DEAE-dextran, and low temperature on reproduction of influenza A, B, and C viruses and their reassortants in diploid and continuous cell cultures was determined. Lowering of pH in the maintenance medium to 6.5 was found to decrease reproduction of influenza A (H1N1) and A (H3N2) viruses and increase that of influenza B viruses.

[The acceleration of experimental influenza B infection under the influence of gangliosides].

The influence of mono-, di-, and trisialogangliosides on the dynamics of influenza B virus reproduction in human embryo fibroblast (HEF) cell culture and human diploid cells was established. The cells were treated with neuraminidase of non-cholera vibrio for removal of natural receptors followed by treatment with gangliosides. Virus reproduction was assessed by infectious titres for chick embryos and HA test of the culture fluid at certain intervals.

[The sensitivity of a number of cell cultures to different types of influenza viruses and their reassortants].

The study of reproductive activity of human and animal influenza A, B, and C viruses as well as influenza A virus reassortants in some cell cultures allowed one to determine the range of cells susceptible for each type (subtype) of the viruses. Differences in the range of cells were demonstrated for different strains of influenza viruses of the same antigenic subtype. It was noted that reassortants of influenza A viruses with the same hemagglutinin subtypes as the parental strains had a wider range of susceptible cell lines and a higher reproductive capacity in these cells.