Abstract
Lymphoid neoplasms occurring in three different (C3H/He, C57BL/6, and B6C3F1) strains of female mice after injection of the bone-seeking and alpha-emitting radionuclide, 239Pu citrate were compared by immunohistochemistry with those from the alkylating agent, N-methyl-N-nitrosourea (MNU)-injected mice. There was a variety of phenotypes from either T-cell to B-cell or histiocytic lineages in lymphoid neoplasms of the control, saline-injected mice. While strain differences were noted in the incidence and proportion, lymphoid neoplasms occurring early after 239Pu-injection were, however, characterized by B220+ phenotypes but negative for both T-cell-specific markers (Thy 1, CD3) and B-cell markers (CD5, CD19, CD79b) to be classified into pre-B-cell lymphomas derived from progenitor B-cells. In contrast, almost all the MNU-induced lymphomas were shown to be CD3+ or rarely Thy 1+ but B220 - T-lymphoblastic lymphomas. These results indicate differences in immunophenotypic expression but also might reflect different carcinogenic processes between chemical- and radiation-induced murine lymphomas.
