Inhibition of PDGF-C aggravates thrombotic microangiopathy (TMA) in mice. Mice treated with PDGF-C antibody had significantly higher body weight loss (A), serum creatinine (B) and glomeruli exhibiting injury, ie, necrosis, thrombosis, mesangiolysis, or microaneurysms (C), as well as fibrinogen deposition (D). PDGF-C inhibition significantly reduced endothelial area positive for CD31 (E). Corresponding pictures of periodic acid-Schiffs, fibrinogen, and CD31 stainings of glomeruli from mice with TMA treated with PDGF-C-neutralizing antibody (G, I, K) or control IgG (F, H, J) are shown. In sham-treated animals, all assessed parameters were within the normal range and were not affected by PDGF-C inhibition (L–Q). Graphs A–E show individual values of each animal (IgG group as triangles; PDGF-C antibody group as rectangles); the line depicts the mean value for each group. Original magnifications ×400. Glom. – glomerular, s-crea. – serum creatinine. *P < 0.05; **P < 0.01.