Ueno et al, in a CG-stimulated PF rat model, demonstrated that intraperitoneal injection of MSCs suppressed peritoneal expression of α-SMA, FSP-1 and TGF-β; a finding that was associated with improved peritoneal function.22 It is shown that an expanded fibrotic interstitium restricts water transport, as it produces an extra barrier between capillaries and the dialysis fluid. The gene discussed is TGFB1; the disease is pemphigus foliaceus.