Characterisation of a polyomavirus in two foetal rhesus monkey kidney cell lines used for the growth of hepatitis A virus.

Electron microscopy and prolonged incubation of cell cultures have revealed the presence of a papovavirus in two foetal rhesus monkey kidney cell lines, FRhK-4 and FRhK-6, which are used to grow hepatitis A virus. The papovavirus, designated FRKV, was present in culture fluids from both cell lines and in thin sections of FRhK-4 cells. The size of the virus, 47 nm, places FRKV within the Polyomavirus genus. FRKV has been grown in primary human embryo kidney and calf kidney cell cultures. Haemagglutinin has not been demonstrated. Preliminary investigations indicate that FRKV is antigenically identical to or closely related to stump-tailed macaque virus and is not one of the primate polyomaviruses SV40, SA12, BK or JC. FRKV reacts with antibody that occurs in pools of foetal and newborn bovine sera suggesting that the virus might be of bovine origin.