Adaptation of the rabies virus of the production strain "sheep" GNKI to the transplanted cultures of NGUK-1 and ВНК-21/13 CELLS

Abstract

The selection of the optimal line of the transplanted cell culture and the adaptation of the rabies virus to it makes it possible to exclude the use of laboratory animals, fully control the process of obtaining viruscontaining material with high infectious activity in large quantities and with a faster and shorter production cycle. The adaptive potential of various strains of rabies virus varies significantly, in this regard, the aim of the study was to study the sensitivity of the production strain of the rabies virus "Sheep" GNKI to the transplanted cultures of NGUK-1 and ВНК-21/13 cells. The adaptation of the rabies virus to the transplanted cultures of NGUK-1 and VNK-21/13 cells was carried out by sequential passivation. The titer of the virus was calculated by the number of fluorescent foci, the concentration of rabies virus antigen was determined by the ELISA method, the pathogenicity of the virus at the level of 11 passages on different cell lines – on white mice.It was found that the transplanted ВНК-21/13 cell line provided a faster adaptation of the virus and the achievement of maximum titers within 36-48 hours, whereas the NGUK-1 line maintained relatively slow replication and ensured the achievement of maximum titers after 96-120 hours. The optimal multiplicity of infection with NGUK-1 and ВНК-21/13 was 0.1 KKID50/cell, while the titers of the "Sheep" virus strains were 4.11±0.26 and 6.17±0.49 lg KKID50/cm3, respectively. Virus replication in ВНК-21/13 cells was characterized by greater intensity: the antigenic titer of the virus at all passage levels was 1.5-2 times (p<0.05) higher than that in NGUK-1 cells. The positive dynamics of the accumulation of the viral titer persisted until passage 8-9, after which this indicator remained stable until passage 11 inclusive. The results of the assessment of the pathogenicity of the rabies virus at the level of passage 11 on different cell lines showed that the virus adapted to both NGUK-1 and ВНК-21/13 has not lost pathogenicity for white mice. Thus, it was found that the transplanted ВНК-21/13 cell line significantly exceeds the NGUK-1 cell line in terms of replicative capabilities and can be used to develop viral raw materials for the production of diagnostic tools and specific prevention.