Heterogeneity of neoplastic cells derived from a hamster tumor induced by avian sarcoma virus B77

Cells derived from a hamster tumor induced by avian sarcoma virus Bratislava 77 (B77) in vivo, were cultivated in vitro. After few passages two morphologically different cell lines were isolated from the parental culture (B77/H). One cell line consisted of fibroblastic cells (B77/H/fi and the other from epithelioid cells (B77/H/ep). Cells of both lines were highly tumorigenic in neonatal syngeneic hamsters, B77/H/ep cells were able to form colonies in soft agar and contained complete integrated B77 viral genome. In contrast, the B77/H/fi cells grew poorly in soft agar and did not contained B77 virus genome.