RESUMEN
Neonatal BALB/c mice were inoculated (ip) with a recombinant Moloney murine leukemia virus-TB. Majority of the inoculated mice developed lymphoma within 5-7 months post infection. The cells from splenic lymphomas were cultured and 3 continuous cell lines (GP1, GP2 and GP3) developed. GP1 was single cell cloned and characterized. Based on Thy 1.2 (98.4%) phenotypic marker, the cell line was categorized as T cell line. The percent positivity for different cell surface markers on analysis with FACS was 98.4, 4.8, 5.5, 2.2, 1.8, 1.2 and 9.5 for Thy 1.2, mu, L3T4, Lyt2, Ia, IL2R and PNA receptor, respectively. A total of 16.5% GP1 cells was also positive for Moloney murine leukemia virus envelope protein (gp 70). Incomplete retrovirus like particles were demonstrated in the cytoplasm of GP1 cells by electron microscopy. The cell line on inoculation(ip) in neonatal BALB/c mice produced lymphomic lesions in almost all the vital organs of the mice.