Genotypic and phenotypic changes of BHK-21 cells grown in suspension cultures.

The propagation of foot-and-mouth disease virus on BHK-21 suspension cells, although economically convenient, may yield a scarcely immunizing antigen. Helpful insights were obtained by investigating a few genotypic and phenotypic features of the cell cultures. The appearance of polyploid populations, higher cell concentrations at the end of culturing, the progressive reduction of spreading on surfaces and an abnormal expression of the alpha 5 beta 1 integrin were found to be correlated with the number of passages in suspension culture. The observed modifications in the normal course of the cell-cycle and in the expression of some surface proteins point at a possible mechanism of virus damages arising from defective cellular functions.