Effects of autologous plasma from patients with malignant tumor on macrophage migration inhibition with tumor extract.

By the use of the indirect migration inhibition technique blocking or inhibitory effect of autologous plasma on the production of migration inhibitory factor (MIF) from lymphocytes contacted with autologous tumor extract was studied in 45 patients with malignant tumor. When autologous plasma was added to the lymphocyte culture incubated with autologous tumor extract in 44 of these patients, inhibition of migration was completely abrogated in 9 of these patients whose lymphocytes produced MIF when cultured in plasma-free medium. MIF activity was not abolished when autologous plasma was added to the supernatant of lymphocyte culture incubated with autologous tumor extract. Inhibition of migration was not affected by the addition of allogeneic plasma from a normal subject to the lymphocyte culture. In 15 patients, MIF was not produced when lymphocytes were cultured with autologous plasma alone. These results appeared to indicate that autologous plasma of patients with malignant tumor might block or inhibit the production of MIF from lymphocytes contacted with autologous tumor extract.