Increased IL-10 secretion after culture of photodepletion cells with untreated GVHD patient cells. GVHD patient PBMCs were cocultured with equal numbers of autologous untreated (clear) or photodepletion-exposed (filled bars) PBMCs. After 3 days of incubation, supernatants were collected, and (A) IL-10 and (C) soluble TGF-β levels were determined by ELISA. (B,D) GVHD patient PBMCs were cultured for 5 days with equal numbers of untreated (clear bars) or photodepletion-exposed PBMCs from the same patient in the absence (filled bars) or presence of neutralizing mAbs directed against IL-10 (diagonal), TGF-β (checked), or an irrelevant antigen (striped bars) of the same immunoglobulin G1 isotype, and cell proliferation was determined by measuring 3H-thymidine incorporation. Bars represent mean ± SEM of 3 independent experiments. *P < .05.
