MECHANISM OF GLUCOCORTICOID ACTION ON PHYTOHEMAGGLUTININ-STIMULATED LYMPHOCYTE .I. IN VITRO BINDING OF CORTICOSTEROIDS TO LYMPHOID TISSUE

1. 1. The binding of hydrocortisone and cortisone to suspensions of human, rat and rabbit thymocytes and rabbit lymphocytes is presented. 2. 2. Binding quotients were calculated by the ratio of tritiated corticosteroid in the centrifuged cell pellet to an equal volume of supernatant fluid. 3. 3. Evidence for specific and nonspecific binding of glucocorticoids to lymphocytes, as defined by Munck and Brinck-Johnsen1, is presented with rabbit thymocytes. 4. 4. Steroid binding is directly related to cell volume. 5. 5. Using the electronic particle counter, cell size distribution and mean cell volume determinations for rat and rabbit thymus and rabbit lymph node suspensions are presented. 6. 6. The binding of corticosteroids to lymphoid cells may be crucial in the examination of steroid inhibition of antigen-stimulated lymphocytes. © 1969.