Enhancement of defective monocyte function during immunotherapy with recombinant interferon.

The influence of immunotherapy with high dose (50 X 10(6) units/m2) recombinant leukocyte A interferon on blood monocyte functions was studied in eight patients with bronchogenic carcinoma. Monocyte chemotactic responsiveness (MCR) was initially depressed (9.8 +/- 1.6 cells/field) compared to healthy controls (17.6 +/- 5.1 cells/field), P less than 0.01. Recombinant interferon was administered three times weekly, and after 7 days a significant improvement in chemotaxis was observed (16.6 +/- 3.0 cells/field), P less than 0.05. The MCR remained normal until cessation of interferon therapy (greater than 1 month). Phagocytic and candidacidal activities were normal in the patients and were not influenced by treatment with interferon. In conclusion, high dose recombinant interferon given to cancer patients caused a normalization of defective blood monocyte chemotaxis, which persisted for greater than 1 month.