Alteration of macrophage function in AKR/J leukemic mice.

Peritoneal macrophages from AKR/J leukemic mice, a strain which spontaneously develops a virally induced T-cell lymphoma between the age of 8-12 months, were used to study any possible changes in adherence, opsonization, phagocytosis, nitroblue tetrazolium (NBT) reduction and antibody-dependent cellular cytotoxicity (ADCC). Increased adherence, opsonization and phagocytosis of particles and impaired ADCC were found when these macrophages were compared with those from tumor-free BALB/c mice. Moreover, phagocytosis and NBT reduction in macrophages from AKR/J leukemic mice were also found to be increased when compared with macrophages from AKR/J mice in their preleukemic stage. The possibility that the decline in ADCC observed, in spite of the fact that the macrophages were activated and showed an increase in other functional aspects, may be responsible for the defective surveillance of macrophages in tumor development is also discussed.