Figure 1. Inhibition of TH cell proliferation by CD4⁺ Treg clones.

This figure illustrates that Treg clones generated from patients with chronic hepatitis C inhibit proliferation of autologous anti-CD3/anti-CD28 stimulated TH1 and TH2 clones. Inhibition of TH1 and TH2 clones was not altered when direct cell-contact was prevented by co-culture in a semipermeable transwell system. Co-culture experiments with a neutralising IL-10 antibody (10 µg/ml; clone 23738) prevented Treg-mediated suppression of TH1 and TH2 clones indicating that inhibition of TH1 and TH2 clones by Treg clones involved IL-10 production as a major soluble inhibitor. Proliferative responses were studied via [³H] thymidine assays. The figures present mean±SEM of experiments with TH1 (filled circles) and TH2 clones (open circles), respectively.