Antigenic phenotype of LEW rat lymphatic leukemia

LEW rat lymphatic leukemia/lymphoma was antigenically phenotyped by means of W3/13, OX7, P4/16 and F 17-23-2 MoAbs. T-cell lineage related markers were proven to be expressed by leukemia cells. AAS prepared in congenic rat strains have shown the following pattern: alpha RT1 (MHC) AAS directed against RT1 antigenic specificities both "public" and "private" gave positive reactions with 100% of leukemia cells, all cross-reacting AAS directed against "public" specificities only, reacted positively too with 17-100% of leukemia cells and no alien specificities have been detected when LEW antisera were tested. The expression of RT5 differentiation antigen was proved on leukemia cells by means of alpha RT5 congenic AAS. T-cell differentiation antigen RT6 was also detected by means of alpha RT6 AAS with closely similar specificity as MoAb P4/16 which also positively reacted with KPH-Lw-I cells. Leukemia T-cell origin is also supported by the absence of class II antigens (F 17-23-2 MoAb) and SIg receptors. A presence of leukemia/lymphoma associated antigen was indicated by AAS absorption analysis.