Immune modulation by ERC. A) In order to assess active proliferation of ongoing MLR 50,000 mitotically inactivated (mitomycin C) PBMC (stimulators) were incubated with 50,000 allogeneic PBMC (responders). Mitotically inactivated ERC were added at the indicated concentrations per well. Cells were cultured for 72 hours. For the last 18 hours of culture, cells were pulsed with 0.5 μCi 3H-thymidine. B&C) Ongoing MLR was established as described and supernatant was collected at48 hours. IFN-gamma and IL-4 were assessed by Quantikine Sandwich ELISA (R&D Systems, Minneapolis). D) Suppression of TNF-alpha production by ERC Conditioned Media. ERC conditioned media was added to mouse splenocytes that were activated with 2.5 microliters of LPS in a total volume of 200 microliters. The concentration of splenocytes was 250,000 cells per well. After culture for 48 hours, supernatant was examined for TNF-alpha by ELISA (R&D Systems). Error bars represent ± Standard Deviation.