Immunological studies on Burkitt ' s lymphoma Leukemia

A FEW years ago, it became clear, in the progress of experimental tumor immunology'-7 that all virusinduced tumors carry a common, group-specific transplantation antigen, capable of inducing rejection reactions in syngeneic hosts. The question arose whether it would be possible to utilize this fact for the search after possibly similar, virally determined transplantation antigens in tumors of unknown etiology, particularly human. Our attention turned to Burkitt's lymphoma for three reasons: (a) its postulated viral etiology8; (b) clinical observations'-" strongly suggesting that host-defense reactions may plan an important role in this disease and decisively influence the outcome of chemotherapy; (c) among the virally induced experimental tumors, lymphomas lend themselves particularly well for the demonstration of virally determined common antigens, partly because it is easy to prepare free-cell suspensions, with a high frequency of viable cells, and partly because humoral antibodies are more easily demonstrable, as a rule, against surface antigens carried on lymphoma cells than on large carcinoma or sarcoma cells. The first question we asked appeared quite straightforward: was it possible to obtain by testing the reactivity of live Burkitt lymphoma (BL) cells, with patients' sera, and in comparison with appropriate controls, evidence that would indicate the existence of characteristic cell-membrane-associated antigens, in analogy with the virally induced murine leukemias and, if so, could this information help to elucidate the etiology of the disease, as well as the possible role of host defense reactions that may influence its clinical course? To approach this problem, we chose the technique that was most