Up-regulation of selected proteins in the cell supernatant of fibroblasts upon IL-1β treatment. Successful inflammatory activation in fibroblasts upon IL-1β treatment was demonstrated by up-regulation of known inflammation-induced proteins. The mean number of distinct peptides identified per protein in the respective cell supernatants, determined from at least three independent experiments, was used. Significant up-regulation was determined using the Chi-squared test (*, p <0.05). (A) Up-regulation of IL-6, GRO-alpha and CXCL5 in IL-1β treated skin fibroblasts. (B) Up-regulation of IL-8 in IL-1β treated skin, lung (NHLF) and BM fibroblasts.