Preleukemic expression of TL antigens in x-irradiated C57BL/6 mice

Anomalous appearance of TL (thymus-leukemia) antigens is a characteristic feature of radiation-induced leukemias of C57bl/6 mice. We now report that thymocytes of irradiated C57BL/6 mice express TL antigens long before the development of overt leukemia. Thus, TL is a marker for preleukemic changes occurring during radiation leukemogenesis. Low levels of murine leukemia virus (MuLV)-related antigens are also detected on preleukemic thymocytes. Comparative tests on individual mice show no direct correlation between TL and MuLV antigen expression.