Cytochalasin B-induced changes in concanavalin A-activated lymphocytes.

Cytochalasin B (CB) administered simultaneously with a mitogenic dose of concanavalin A (Con A) interferes with the activation process. This interference involves structural alterations of cellular membrane which do not include a reduced Con-A-binding capacity. This conclusion is supported by the observation of deformities in both nuclear and cytoplasmic membranes in Con A-activated lymphocytes subsequently treated with CB. The high incidence of membrane blebs and pseudomyelin bodies in the cytoplasm points to a general effect of CB on the structural organization of membrane which may secondarily interfere with some specific event such as generation or transfer of signals for activation or cytokinesis.