[The induction of the migration of bone marrow stem elements to the periphery by the cytokines of cortisone-resistant thymocytes].

We present evidence about the functional activity of factors produced by cortisol-resistant thymocytes. Experiments in vivo have shown that the administration of the supernatant prepared from cortisol-resistant thymocytes leads to a strong stimulation of endogenous colony formation, significantly prolongs survival of sublethally irradiated mice, increases the rate of restoration of the number of thymocytes in the thymus after sublethal irradiation, and contributes to the recovery of the humoral immune response of nude mice to T-dependent antigens. The results obtained suggest that along with other cytokines, cortisol-resistant thymocytes spontaneously produce a chemotactic factor inducing migration of stem cells from the bone marrow to the periphery.