OBTAINING AND STUDYING IN VITRO OF THE RECOMBINANT VIRUS OF THE AFRICAN SWINE FEVER WITH A238L GENE DELETION

African swine fever (ASF) is a deadly and dangerous viral disease of pigs and wild boars, which leads to significant economic losses. Despite the progress in the study of immunopathology in ASF, the creation of a universal effective and safe vaccine against ASF virus has not been successful so far. This is due to the complex structure of the virus, the high variability of the genome and the presence of a large number of immunomodulating proteins. As is the case with other large DNA viruses, the ASF virus genome encodes several proteins that help the virus evade the host's immune response. One of them is the powerful immunosuppressant protein 5EL (A238L gene) - an IkB homolog and calcium neurin phosphatase inhibitor that causes programmed cell death. The aim of the study was to obtain a recombinant ASF virus with deletion of the A238L gene by homologous recombination and to study its reproduction in vitro. As a result, a recombinant Volgograd / 14c ΔA238L ASF virus was obtained from the strain of ASF virus «Volgograd / 14c» in the transplanted cell culture COS-1. According to the results of our studies, the removal of the A238L gene from the virulent Volgograd / 14c strain did not lead to a change in the cultural properties of the recombinant Volgograd / 14c ΔA238L virus in the transplanted cell culture COS-1. Reproduction of the recombinant strain Volgograd / 14c ΔA238L in primary culture of pigs macrophage cells and COS-1 cell culture is 4.0-5.0 lg GAE 50 / cm³. There were no differences in the the dynamics of reproduction of the initial and recombinant strains. It was shown that reporter fluorescence of the EGFP gene is observed at different multiplicity of infection (0.1 and 1), which indicates the effective replication of the virus

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