Macrophage polarization in cesarean scar diverticulum

Abstract

AimsTo determine immunohistochemical features and correlations between M1/M2 polarization status with disease severity of post-cesarean scar diverticulum (CSD).MethodsHistological and immunohistological staining were performed and inflammatory (CD16, CD163, and TNF-α), fibrosis (α-SMA), and angiogenic (CD31) markers were examined in uterine tissues collected from patients with uterine scar diverticula (CSD) (n=37) and cesarean section (CS) (n=3).ResultsCSD tissues have higher expression of α-SMA, TNF-α, CD16, and CD31 and lower expression of CD163 than CS tissue (P <0.05). Compared with adjacent tissues, thick-walled blood vessels, glands, and fibrotic sites have higher expression of α-SMA, TNF-α, and CD16. Statistical correlation was observed between the expression of CD16 and TNF-α (R = 0.693, P <0.001), α-SMA (R = 0.404, P <0.05), and CD31 (R = 0.253, P <0.05) in CSD tissues, especially with the ratio of CD16/CD163 (R = 0.590, P <0.01). A more significant difference was observed between the expression of CD16/CD163 and α-SMA (R = 0.556, P <0.001), TNF-α (R = 0.633, P <0.0001) and CD31 (R = 0.336, P <0.05) Statistical correlation.ConclusionIn this study, TNF-α, α-SMA, CD16, and CD31 proteins were overexpressed in all CSD cases, and CD16/CD163 was positively correlated with tissue inflammation, fibrosis, and neovascularization. Abnormal mononuclear macrophage infiltration may be involved in the origin and progression of CSD.