Suppression of natural killer activity and antibody-dependent cellular cytotoxicity by cultured human lymphocytes
Article
Nair, MPN, Schwartz, SA. (1981). Suppression of natural killer activity and antibody-dependent cellular cytotoxicity by cultured human lymphocytes
. JOURNAL OF IMMUNOLOGY, 126(6), 2221-2229.
Nair, MPN, Schwartz, SA. (1981). Suppression of natural killer activity and antibody-dependent cellular cytotoxicity by cultured human lymphocytes
. JOURNAL OF IMMUNOLOGY, 126(6), 2221-2229.
Human PBL precultured in media demonstrated decreased NK and ADCC activities that were apparently the effect of endogenous suppressor cells generated in the culture. PBL precultured with Con A (60 μg/ml) showed further decreases of NK and ADCC activities. Precultured PBL also expressed suppressor effects on the NK and ADCC activities of both autologous and allogeneic effector cells in mixing experiments. Suppressor cell activities could be enhanced by preculturing PBL with Con A for 72 hr. Suppression of NK activity was more pronounced against autologous effector cells, whereas suppression of ADCC activity was greater against allogeneic effectors. PBL precultured with other polyclonal activators, PHA and PWM, at a concentration of 60 μg/ml failed to demonstrate any suppressor activity on NK and ADCC effector cells. PBL precultured with Con A at a lower concentration (5 μg/ml) showed a helper effect in cocultures. Suppressor activities of culture-induced and Con A-activated PBL on ADCC effector cells were proportional to the cell dose and were resistant to irradiation administered in vitro. The suppression of NK and ADCC activities observed here was not due to crowding, cell death, steric hindrance, generation of cytotoxic cells or cold target competitive inhibitors, or binding of effector cells. The results strongly support the premise that, like other lymphocyte functions, NK and ADCC activities, themselves potentially immunoregulatory, are also under active immunologic control.
