[Thymic hormonal effects on the antigen-dependent differentiation of accessory T-lymphocytes in the humoral immune response].

In the conditions of experimental deficiency of serum thymic factor (FTS) theophylline (TP) recovers in the post--thymic precursors of helper T lymphocytes an ability for differentiation to the effector regulatory stage and inhibits this process in the normal conditions. In the same conditions fraction 2 of thymosin (F2T) recovers this process and in combination with TP can relieve its opposite effects. The diversity of action of F2T on the differentiation of the post--thymic precursors of helper T lymphocytes is accounted for by the possibilities of realisation of the F2T and STF hormonal signals to these cells which depend on the condition of their specific receptors controlled by intracellular cAMP levels.