Figure 4.

PCI concentration and SSc fibroblast apoptosis in co-cultures exposed to either IL-17A or IL-17A+α-IL-17A mAb. (A) Shows that concentrations of PCI in supernatants from SSc PBMC–fibroblast co-cultures treated with ectopic rhIL-17A 6.25 ng/ml are decreased, while simultaneous treatment of these co-cultures with ectopic rhIL-17A and a neutralizing mAb against IL-17RA subunit, α-IL-17A mAb16 μg/ml, increases PCI production (number of samples per group = 3). (B) Shows that α-IL-17A mAb at the same concentration is able to reduce significantly the apoptotic rate of co-cultured SSc fibroblasts exposed to rhIL-17A (number of samples per group = 5). Data are mean ± SD, paired Student's t-test. **p < 0.01. The scatterplot graph in panel (C) shows the percentage of apoptotic fibroblasts co-cultured with autologous PBMCs obtained from a representative SSc patient, added with ectopic rhIL-17A 6.25 ng/ml. The scatterplot graph in panel (D) shows the percentage of apoptotic fibroblasts co-cultured with autologous PBMCs obtained from the same representative SSc patient, added with both ectopic rhIL-17A 6.25 ng/ml and α-IL-17A mAb16 μg/ml.