Abstract
Disodium 4-chloro-2, 2'-iminodibenzoate (CCA) markedly suppressed the PFC response of pokeweed mitogen (PWM) stimulated human peripheral lymphocytes. IgM-PFCs were clearly reduced in the concentration from 0.01 to 0.1 mcg/ml of CCA. Although IgG-PFCs were decreased gradually in higher concentration from 0.1 to 1.0 mcg/ml, the pattern of reduction was different from IgM-PFC reduction. CCA (0.1 mcg/ml) was added to the cultures at the various time after cultivation and PFCs were measured. The suppressive effect of CCA on IgM-PFC was observed in initial stage of the cultivation, in late stage, however, the suppressive effect was not observed. To study whether CCA inhibits directly B cell proliferation or not, purified B cells were cultivated in the presence of 0.1 mcg of CCA and helper factor as a substitute for T cell. The differentiation of B cells to immunoglobulin producing cells was not inhibited in this experimental system. These results suggest that the suppressive effect of CCA on B cell differentiation may be due to accerelate the suppressor T cells or decrease the helper function of T cells.
