PDGFB and Peritoneal Fibrosis: Thus, TGFβ1 promotes peritoneal fibrosis and dysfunction [37], [39], PDGF-B promotes angiogenesis [38], IL-6 and its soluble receptor (sIL-6R) control the pattern of leukocyte recruitment during peritoneal inflammation [40] and the IFNγ/TNFα combination promotes mesothelial cell apoptosis [23].