Effect of immunochemotherapy with OK-432 and yeast cell wall on the activities of peritoneal macrophages of mice.

The effect of chemotherapy combined with immunostimulants on the activities of macrophages in mice was studied. The number of macrophages and exudate cells in the peritoneal cavity increased 3 days after ip injection with mitomycin-C, cyclophosphamide, and 5-fluorouracil together with OK-432 or yeast cell wall and decreased to normal level after 9 days, while the number of the cells remained decreased in mice receiving multi-drugs alone. Acid phosphatase activity of the macrophages of mice was elevated after the simultaneous injection of yeast cell wall and OK-432, and high activity was preserved in the macrophages of mice receiving yeast cell wall even after 9 days. Spreading of these cells was also enhanced. Macrophage activities examined by these assays were maximal in every respect 6 days after combination therapy. Cytostatic activity of the cells was strengthened after 6 days by combined use of OK-432 or yeast cell wall. Role of the activated macrophages in combination therapy was discussed.