Demonstration and genotyping of pestivirus RNA from mammalian cell lines

We examined 20 cell lines of various animal origins for the presence of pestivirus contamination by the reverse transcription-polymerase chain reaction (RT-PCR), and found 15 (75%) cell lines were positive. The RT-PCR products of the 5' untranslated region (UTR) of pestivirus genome were sequenced and subjected to genotyping. Stem-loop structures at three variable regions in the 5' UTR render genotyping of the contaminated pestiviruses. Bovine cell lines tested were all contaminated with genotypes I, II, or III of bovine diarrhea virus (BVDV). Cell lines of canine, feline, and primate origin were contaminated with genotype II of BVDV. Cell line Ch1Es of caprine origin was contaminated with border disease virus (BDV).