Effects of IFN-γ on proliferation and apoptosis of intestinal MCs. (A/B) MCs were cultured for 3 days in the conditions described in Figure 1C-F. (A) [3H] thymidine (0.5 Ci/well) was added for the final 12 h of culture to assess MC proliferation. Incorporation of [3H]thymidine into the cells was measured and is depicted as cpm/103 MCs. Mean ± SEM of 5 (medium and SCF 5 ng/ml) or 7 independent experiments (SCF 50 ng/ml and SCF + IL-4) performed in duplicates. (B) Caspase 3/7 activity was determined and is shown as fluorescence units/103 MCs. Mean ± SEM of 5 independent experiments performed in duplicates. (C) Surface binding of annexin V measured by FAVS following culture of MC for 3 days with IFN-γ (100 ng/ml) or medium alone. One representative experiment out of two is shown. *p < 0.05; **p < 0.01.