Tolerogenicity of thymic epithelium

S R Webb1, J Sprent

  • 1Department of Immunology, Research Institute of Scripps Clinic, La Jolla, CA 92037.

To attempt to resolve the controversy on the role of thymic epithelial cells (TEC) in tolerance induction, athymic mice were grafted with allogeneic day-14 fetal thymuses treated with deoxyguanosine in vitro. The data indicate that the tolerogenicity of TEC varies considerably according to the antigen and the subpopulation of T cells studied. For cytotoxic CD8+ cells responding to H-2 class I antigens, TEC induce minimal tolerance. For proliferative responses of CD4+ cells, by contrast, TEC induce significant tolerance to H-2 class II antigens but no detectable tolerance to Mlsa antigens.

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