Malignant immunoblastoma: Immunoglobulin synthesis and the progression to leukemia in heterotransplanted acute lymphoblastic leukemia, chronic lymphatic leukemia, lymphoma, and infectious mononucleosis

Abstract

The heterotransplantation of cells from human subjects with overt lymphoid neoplasia or infectious mononucleosis into newborn Syrian hamsters treated with antilymphocyte serum results in serially transplantable malignant tumors. These tumors are composed of cells retaining human species-specific antigen at the cell surface, and hence represent progeny of the implanted human cells rather than tumor cells induced in the hamster by an oncogenic agent. The tumors appear to fall into two categories on the basis of their behavior in the hamster. Category A consists of tumors derived solely from subjects with acute lymphoblastic leukemia secondary to lymphosarcoma, which in the hamster progress to acute leukemia and apparently do not secrete immunoglobulins. Category B consists of tumors derived from all of the remaining diagnostic categories thus far investigated and from acute lymphoblastic leukemia in remission as well, which in the hamster secrete immunoglobulins of human type and do not progress to acute leukemia. The descriptive term “malignant immunoblastoma” is provisionally proposed for the category B tumors, to emphasize their experimental derivation as well as their relationship to cells of the immunoglobulin-secreting type. The hypothesis is advanced that the category A acute leukemias and the category B malignant immunoblastomas therefore may be related to T and B lymphocytes, respectively. The oncogenicity in hamsters of directly injected peripheral blood buffy coat cells from subjects with infectious mononucleosis raises the possibility that this lymphoproliferative disease may be a benign, self-limiting form of lymphoma. These observations with infectious mononucleosis may provide inferential evidence for the existence in man of hostregulatory, cancer-preventing mechanisms of perhaps substantial importance.