[The role of the cytoskeleton in lymphocyte stimulation]

The influence of the cytoskeleton active drugs Cytochalasin B and Colchicine on the 3H-thymidine and 14C-uridine incorporation of Con A stimulated lymphocytes of mice was studied. Both drugs had no influence on the entry of the Con A incubated lymphocytes into the G1-phase but inhibited significantly the entry into the S-phase of the cell cycle. Cytochalasin B and Colchicine differ in their effect on the release of charge changing lymphokines. Colchicine did not influence this release in contrast to Cytochalasin B. The results show that both Cytochalasin B and Colchicine suppress cellular processes which are necessary for going beyond the commitment point. A possible importance of the microfilaments for the release of lymphokines and of the microtubuli for the expression of lymphokine receptors is discussed.