Aetiology of jaagsiekte: experimental transmission to lambs by means of cultured cells and cell homogenates.

Studies on the transmission of jaagsiekte (ovine pulmonary adenomatosis) both by subinoculation of cells of known sex and by cell homogenates into male and female lambs are reported. The results obtained indicate a thymocyte-dependent rejection of male cells in female recipients in contrast to the successful transplantation of male cells in male animals and female cells in both sexes. This suggests the presence of a surface antigen determined by the gamma-chromosome in the tumour cells. A second mechanism of transmission, dependent on the transformation of the recipient's cells, was demonstrated by 2 cases of heterologous transplantation and confirmed by inoculation of cellular homogenates.