Calpain and caspase inhibitors enhance the survival of eosinophils. (A) PBEos were left untreated (0), treated with TGF-β1 (0.5 ng/ml), IL-5 (3pM) or IL-5 (3pM) plus TGF-β1 (as shown) and stained with annexin-V/PI and analyzed by FACS after 72 h. Data presented as a percentage of viable cells at time 0. (B) PBEos were left untreated (−) or treated with TGF-β1 (0.5ng/ml), IL-5 (3pM), calpeptin (CalP, 20μM) or caspase 3 inhibitor (CaspI, 25μM), assessed by FACS as in (A) after 72 h of incubation and presented as a percentage of viability at time 0. (C) PBEos were untreated (C) or treated with TGF-β1, lysed and analyzed by immunoblot for full-length or cleaved PARP (C PARP) and full-length or cleaved caspase 3 (C Casp3). For panels (A) and (B), **; P< 0.01 (one-way ANOVA). Data are representative of at least three experiments with 3 different donors (error bars, SEM of triplicate donors).