Effect of polybrominated biphenyls on the growth and maturation of human peripheral blood lymphocytes

Polybrominated biphenyls (PBB) have been shown to affect the immune system of exposed Michigan farm workers and their families. The purpose of this study was to evaluate the effects of PBB on the function and on the synthesis of immunoglobulins by peripheral blood lymphocytes. Concentrations of PBB as low as 0.001 microgram/10(5) cells decreased lymphocyte response to pokeweed mitogen; higher concentrations of PBB stimulated the in vitro synthesis and release of immunoglobulins. PBB had no effect on the quantity of E-rosette-forming cells, the total T or B cells, or the ratio of helper to suppressor T-cell subpopulations. Enhanced release of IgG was identified in lymphocyte cultures obtained from blood specimens of PBB-exposed Michigan farmers. The data from this study suggest that PBB exerted an adverse effect on cell function, but produced a nonspecific activation of B lymphocytes.