TNF-induced tumor necrosis in bone marrow chimeric mice. Tumor (wt BFS-1)-bearing C57BL/6 wt mice reconstituted with wt bone marrow (wt→wt, n = 7, ○, •), TNFRp55−/− mice reconstituted with wt bone marrow (p55−/− →wt, n = 11, ⋄, ♦) or wt mice reconstituted with TNFRp55−/− bone marrow (wt→p55−/−, n = 16, ▵, ▴) were treated with PBS (100 μl, ○, □, ⋄) or rmTNF (5 μg in 100 μl PBS, •, ▪, ♦) i.p. and tumor necrosis was determined 2 days after treatment. Pooled results from two experiments with at least three mice per group are shown. P values for the comparison of the PBS versus rmTNF-treated groups: *P < 0.05.