Immunological monitoring in lung cancer: use of the leukocyte migration inhibition assay.

The agarose microdroplet leukocyte migration inhibition assay has been applied to the management of patients with lung cancer. Sera of patients with various stages of the disease were assayed in the indirect LMI system for their influence on the LIF production of normal leukocytes. A probably cell-mediated immunity blocking activity could be detected both in the serum of patients with inoperable tumours and in that of operable patients before and two weeks after surgery. The activity, however, disappeared in two thirds of the cases in about 6 months after surgery. The immune competence of patients with inoperable tumours was investigated before and during combined chemotherapy. A positive correlation was established between the tuberculin skin reactions and the leukocyte migration inhibition obtained in the direct LMI assay against PPD, but only in the presence of autologous serum. Sera of patients were also tested for putative in vivo LIF activity by their effect on the migration of autologous leukocytes. A significant correlation between anergy to PHA, as evaluated by skin testing, and the migration inhibition caused by sera was found. When, however, sera from healthy persons and from patients with chronic bronchitis or lung cancer were compared for their effect on the migration of normal leukocytes, no difference could be detected among the three groups. Single doses of the drugs temporarily weakened the skin reactions to PHA and the migration inhibition to PPD in autologous serum, but activity was restored when the drug influence had ceased.