PHYTOHEMAGGLUTININ-DEPENDENT T-CELL PROLIFERATION IS NOT IMPAIRED BY MORPHINE

Opioids have been reported in the literature to have immunosuppressive properties. Thus, we investigated the influence of morphine, morphine -3-glucoronide and morphine-6-glucoronide in vitro on phytohemagglutin in-stimulated proliferation of peripheral mononuclear cells from healt hy humans. Furthermore, the effects of a 1-week treatment with morphin e in a range of 30-240 mg/day on proliferation of lymphocytes from pat ients with chronic pain syndromes were evaluated. In addition, human p eripheral mononuclear cell membranes were tested for specific opioid r adioligand binding. The results show that i) morphine and its main met abolites do not influence mitogen-induced T-cell proliferation, ii) tr eatment of patients with sustained release morphine for 1 week did not impair the lymphocyte proliferative response, and iii) no specific bi nding of mu-, delta- and kappa-radioligands could be demonstrated to m embranes of peripheral lymphocytes obtained from healthy humans. These results do not indicate an impairment of phytohemagglutinin-induced T -cell proliferation during pain treatment with sustained release morph ine.