Immunologic study of T and B lymphocytes in thymectomized monkeys after irradiation and autologous bone marrow transplantation.

Rhesus monkeys were exposed to total-body gamma-irradiation (60Co) with 700R following adult thymectomy, and then protected with autologous bone marrow. Transplantation immunity in TxIBM animals was impaired: skin allografts survived for 19 to 38 days. The percentage of T and B lymphocytes studied by the rosette technique and immunofluorescent staining for Ig did not substantially change when examined in early as well as late periods after TxIBM. Functional capacities of lymphocytes were measured in vitro by stimulation with phytohaemagglutinin and with allogeneic cells in mixed lymphocyte cultures. MLC reactivity in TxIBM monkeys did not recover in the early and later periods following treatment. PHA responsiveness was retained in both these periods. These findings together with the results obtained in the analysis of unstable chromosomal aberrations suggested that PHA-responsive and MLC-reactive cell subpopulations of monkey blood lymphocytes differed in the degree of thymus dependence.