Influence of chemotherapy on superoxide anion-generating activity of polymorphonuclear leukocytes in patients with lung cancer

The superoxide anion (O) generating activity of polymorphonuclear leukocytes (PMN) in peripheral venous blood obtained from 15 patients with lung cancer was measured weekly after drug treatment. The amount of Ogenerated by the cells before chemotherapy was 5.74 ± 0.42 nmol/minute/106 cells (mean ± SE). The value decreased gradually and reached a nadir of 1.98 ± 0.24 at 2 weeks after chemotherapy, at which time PMN count also reached a nadir of 1359 ± 251/μl (mean ± SE). The decreased Ogenerating activity of the PMN recovered gradually thereafter and reached the level seen before the chemotherapy at 4 weeks. Expression of Fc receptors on the plasma membrane in PMN was measured after chemotherapy by the binding of iodine 125 (125I)-immune complexes to the cells. Almost 40% decrease of the binding was observed in the cells obtained at 2 weeks after chemotherapy, compared with that in the cells before chemotherapy. These results indicate that PMN present in peripheral blood at 2 weeks after chemotherapy are not fully matured, in terms of Ogenerating activity and the expression of Fc receptors.