Alterations in the cellular-mediated immune responsiveness of chronic marihuana smokers

Chronic marihuana smokers and matched nonsmokers were compared with respect to several aspects of both their humoral and cellular immune system. Immunoglobulin and complement levels, SMA 12 and hematologic values from marihuana smokers did not differ significantly from those obtained from nonsmokers. However, the number of T-lymphocytes with respect to the ratio of T and B-lymphocytes in the peripheral blood was lowered in marihuana smokers. In addition, phytohemagglutinin stimulation of lymphocytes was apparently less effective in smokers. The polymorphonuclear leukocytes (PNM) from the blood of smokers contained fewer cells capable of phagocytizing yeast cells than did PMN from nonsmokers. While marihuana smoking does appear to affect immune mechanisms at no time in these studies were any deleterious physiological effects that could be directly associated with the alterations in the immune system observed in the marihuana smokers.