Heterologous tumor growth patterns induced in related MHC-defined chicken lines by separate isolates of an avian sarcoma virus strain.

Different patterns of tumour growth resulted from inoculation of separate isolates of the Subgroup C Bratislava 77 strain (B77) of Avian Sarcoma Virus (ASV) into three closely-related inbred lines of chickens. The major genetic difference between these chicken lines is that each is homozygous for a different MHC haplotype. Since for one of the viral isolates, resistance to progressive tumour growth has been shown to be controlled by MHC-linked genes, the data presented here suggest that MHC-controlled tumour rejection operates on viral or cellular determinants different from those which define classical viral group of subgroup specificity.