The main findings are high sTWEAK levels in peritoneal effluents during human peritonitis, a correlation of peritoneal tissue Fn14 receptor expression with peritoneal injury in long-term PD, and the observation that in vivo TWEAK activates Fn14-expressing cells mesothelial cells and promotes peritoneal inflammation in mice. The gene discussed is TNFRSF12A; the disease is peritonitis.