Figure 2. Macrophage-derived IL-10 promotes intestinal mucosal wound healing.
(A) Endoscopic images of healing colonic mucosal wounds 1 and 3 days after biopsy-induced injury in Il10–/– versus Il10+/+ mice and quantification of wound repair (***P < 0.001; n = 5 mice, average of 3 wounds, mean ± SEM). (B and C) Endoscopic images of healing colonic mucosal wounds 1 and 3 days after biopsy-induced injury in Rag1–/– versus Rag1+/+ mice and IL-10fl/flCD11c Cre versus IL-10fl/fl mice and quantification of wound repair (***P < 0.001, n = 5 mice, average of 3 wounds, mean ± SEM). (D) Il10 mRNA levels in intact colonic tissue and day-2 post-injury wounds in IL-10fl/flCD11c Cre and IL-10fl/fl mice (***P < 0.001, n = 5, mean ± SEM). (E) Confocal micrographs of punch biopsies from IL-10 GFP reporter mice with resealing colonic wounds (2 days after injury) showing staining for GFP, F4/80, F-actin (phalloidin), and nuclei. Scale bar: 20 μm. Original magnification, ×40. White asterisks highlight IL-10–GFP colocalization with the macrophage marker F4-80. (F) Il10 mRNA–normalized levels of immune cells isolated from wounded LP colonic tissue on different post-injury days and intact tissue (*P < 0.05 and ***P < 0.001; n = 5 mice, image is representative of 2 separate experiments, mean ± SEM). (G and H) Representative plots of LP myeloid cells isolated from intact and wounded tissue from IL-10fl/fl and IL-10fl/flCD11c Cre mice and stained for Ly6C and F4/80 (n = 10, mean ± SEM). All statistical comparisons were performed using ANOVA with Tukey’s multiple comparisons post test. WD1, 1 day after wounding; WD3, 3 days after wounding.