PROMOTION OF INTRATHYMIC T-CELL DEVELOPMENT BY MHC-Ia-POSITIVE THYMIC MACROPHAGES (Ia + Mø)

The generation of the peripheral T-cell pool is attributed to maturation and differentiation events occurring within the thymus. Three thymic compartments, thymic epithelial cells, thymic hormons and thymic Mo are considered to contribute to the intrathymic T-cell development. While, as we have shown earlier, murine as well as human MHC-Ia-negative-Mo (Ia−Mo) regulate thymocyte (TH) differentiation via suppressive effects (Thymus,6:295,1984) and MHC-Ia+-Mo are involved in intrathymic tolerance induction (Pediatr Res,15:800, 1984), now the contribution of Ia+Mo to intrathymic lymphopoiesis was investigated. An isolation method yielding cell suspensions highly enriched for Ia+ thymic Mo was p…