Nitrite production following the interaction between autologous human B lymphocytes and natural killer cells

Previous studies have shown that autologous B and NK cells cooperate in vit ro, generating immunoglobulin production and switching. In order to underst and this effect, we have assessed the production of nitrites in the superna tant of autologous B and NK cells that were cultured for 48 h alone or mixe d in ratios of 5:1, 2.5:1 and 1:1. There were no significant differences in nitrite concentration independently of the conditions used. However, when cultures were performed with allogeneic cells in a B: NK ratio of 1:1, nitr ite production markedly increased from 485 +/- 115 up to 2,252 +/- 354 nmol /l (P < 0.0001). We conclude that without allogeneic stimuli, there is no n et increase in nitrite production. Nitric oxide metabolism does not seem to be involved in immunoglobulin production and switching. Med Sci Res 27:587 -588 (C) 1999 Lippincott Williams & Wilkins.