A study on the susceptibility of minipig kidney (MPK) and rabbit kidney (RK13) cell line cultures to the lapinized Chinese strain of hog cholera virus.

: The susceptibility of two established cell lines of pig (MPK = minipig kidney) and rabbit (RK13 = rabbit kidney) origin to the lapinized Chinese (LC) strain of hog cholera virus (HCV) was studied. Spleen cells from rabbits infected with the virus under study were inoculated to cell cultures of either MPK and RK13 cells and subsequent passages were made by culturing the trypsinized infected cells with the normal cells. Only the MPK cell line appeared to be susceptible to virus replication. Since no cytopathic effects (CPE) were observed, the presence of the viral antigen in the inoculated cultures was detected by immunofluorescence tests. The virulence of the virus for rabbits was enhanced after its cultivation in MPK cell cultures. When the MPK cell culture system adapted virus was tested in neutralization trials in the presence of an HCV reference immune serum it was found that the virus did not modify its antigenic structure in any extent. Finally, the culture adapted virus appeared to be more immunogenic for rabbits than the original rabbits adapted virus. Based on these results, it seems reasonable to suggest the use of MPK cell line for the propagation of the LC strain of HCV as an alternative to the use of rabbits for the preparation of HCV vaccine.