Skip to main content
. 2015 Dec;185(12):3258–3273. doi: 10.1016/j.ajpath.2015.08.009

Figure 2.

Figure 2

Peritoneal MCs give rise to myofibroblasts in peritoneal fibrosis. A: Experimental design. After two tamoxifen injections into Wt1CreERT2/+;R26TGfl/fl mice, MCs change from the expression of Tomato to membrane-tagged GFP. Two weeks after tamoxifen injection, the mice were treated with CG by 10 intraperitoneal injections. B: Immunohistochemistry of GFP (green) and GPM6A or PDPN (red). After tamoxifen injection into Wt1CreERT2/+;R26TGfl/fl mice, only GPM6A+ or PDPN+ MCs express GFP (arrowheads). Note that no GFP expression in fibroblasts (arrows) is evident. No induction of GFP was observed in the control Wt1+/+;R26TGfl/fl mice (Cre-) after tamoxifen treatment. C–E: Phenotypic changes of MCs in peritoneal fibrosis. The body wall tissues 1 day after CG injections (1, 3, or 10 times) were immunostained with GFP (green) and ACTA2, GPM6A, or COL IV (red). After a single CG injection, GFP+ MCs begin to express ACTA2 (arrowheads). After three CG injections, GFP+ cells in the connective tissue show a myofibroblastic structure with ACTA2 expression but not with GPM6A (double arrows). After 10 CG injections, a few MCs expressing GPM6A survive on the body wall (arrowheads), and no COL IV is observed on the surface of the body wall, indicating denudation of the MC layer. F: Immunohistochemistry of GFP (green) and cell markers (red) after 10 CG injections. Arrowheads indicate the surface of the body wall. MC-derived GFP+ myofibroblasts express PDPN, COL I, and DES but not KRT8, KRT19, F4/80, and CD31 (double arrows). Immunostaining without primary antibodies does not show signals (Negative). Nuclei were counterstained with DAPI. n = 3 (B); n = 2 (C–E, after a single injection and after 3 injections); n = 3 (C–E, after 10 CG injections); Scale bar = 10 μm. ACTA2, α-smooth muscle actin; CG, chlorhexidine gluconate; COL I, type I collagen; COL IV, type IV collagen; DES, desmin; GFP, green fluorescent protein; GPM6A, glycoprotein M6a; KRT8, cytokeratin 8; KRT19, cytokeratin 19; MC, mesothelial cells; PDPN, podoplanin.