No evidence for foreign H-2 specificities on the EL4 mouse lymphoma

Abstract

GARRIDO et al.^1,2 have recently presented evidence that H–2 antisera react in an anomalous fashion with certain mouse lymphomas. They suggested that such reactions are due to the derepression of ‘silent’ genes in the tumours resulting in the expression of foreign H–2 antigens which are not expressed on normal tissue from the animal of origin. If correct, this theory would have vast implications both for the role of the H–2 antigens on the cell surface and for the mechanisms of leukaemogenesis. Their results, for example, indicated that the C57BL/6 (abbreviated to B6) lymphoma EL4 (H–2^b) was reactive in a complement-dependent microcytotoxicity test with four H–2 alloantisera (D-11, D-19, D-30, D-32), which according to their typing were not reactive against normal lymph node cells of an H–2^b strain. We present evidence here that anomalous reactivities against EL4 are probably not due to the derepression of foreign H–2 antigens, but are more likely to be a result of weak reactivities contained within these antisera against normal components on the lymphoid cell surfaces of B6 mice.