FIG. 2.

T-cell dose dependence of NO production by TNFR^−/− macrophages. Bone marrow-derived macrophages were incubated with increasing numbers of T cells in the presence or absence of anti-CD3 (5 μg/ml), and NO was measured as in Fig. 1. The data show either TNFRp55p75^−/− bone marrow macrophages plus TNFRp55p75^−/− T cells, TNFRp55^−/− bone marrow macrophages plus TNFRp55^−/− T cells, or wild-type bone marrow macrophages plus wild-type T cells. The data represent one experiment showing the mean NO₂ production of duplicate cultures (±SE). Similar results were obtained from six additional experiments.