TNF and AIDS: IHC staining indicated that there was a marked increase in proinflammatory cells expressing IL-1β (median 174 vs. 75 cells/0.8 mm2, p = 0.04) and TNF-α (median 226 vs. 107 cells/0.8 mm2, p = 0.01) in the colon of AIDS patients compared to healthy controls (Fig. 1c and d).