Evidence for Function of Thymic Tissue in Diffusion Chambers Implanted in Neonatally Thymectomized Mice. Preliminary Report

Abstract

Mice of the inbred strains C3Hf/Lw and C3Hf/Bi were thymectomized within 12 hours after birth and subsequently divided into two experimental groups: 1) thymectomized controls; 2) mice implanted intraperitoneally at 3 to 4 weeks of age with a cell-tight Millipore diffusion chamber containing isologous newborn thymus. The controls developed a marked lymphopenia, an involution of all lymphoid tissue, and a severe wasting disease. Death occurred in this group at approximately 7 to 8 weeks of age. Mice with diffusion chambers did not show depletion of lymphocytes in the peripheral blood, involution of the lymphoid organs, or any characteristic sign of the wasting syndrome. In this group the spleens, lymph nodes, and Peyer's patches were rich in lymphocytes and in primary and secondary lymphoid nodules. The lymphoid hyperplasia was especially marked in the Peyer's patches. The restorative action seen in the mice with diffusion chambers is attributed to a noncellular or humoral factor that diffused from the thymic tissue in the chamber, the pore size of which did not allow the passage of intact cells.