Development of efficient vaccines against influenza, yet remaining a serious problem for many countries of the world, is a topical problem. Stable cell lines as a substrate are attracting the attention of influenza vaccine developers. It was demonstrated that unlike the influenza virus adapted to chick embryos, the influenza virus isolated from MDCK culture retains the antigenic properties of epidemiological strain.
Effects of various conditions of cultivation in cells (inoculation dose, compositions of growth and supporting media, and infectious dose of virus) on production efficiency of cold-adapted reassortant vaccine strains of type A and B influenza viruses were studied in experiments.
Selection of optimal biological additions to the nutrient medium, including additions involving plant hydrolysates, provided efficient reproduction of the virus (9.5–10.0 log EID50/ml) in MDCK cell line in the presence of 2 µg/ml trypsin. Stabilizers allowing the culture-grown live virus to be freeze-dried with preservation of the virus infectivity at a level of 8.5 log EID50/ml were studied. The parameters studied are key properties while developing the technology for manufacturing culture live vaccine against influenza using cold-adapted reassortant vaccine strains.