Fig. 4
Histological confirmation and cellular characterization of ectopic endometriotic lesions. (A) Control uterine horn (UH) from healthy mice in the estrous stage displayed normal morphology (H&E, n = 6). (B–D) Ectopic lesions harvested at day 12 post-induction from C57BL/6J, BALB/c, and Swiss albino mice (H&E, n = 6 per group) exhibited characteristic endometriotic features, including singular or multi-layered epithelium, dense immune cell infiltration in the stroma, and the presence of endometrial glands. (E–G) Immunohistochemical analysis of control uterus sections (E–G, Control) revealed (H) proliferating epithelial cells (Ki67+), (I) established vasculature (CD31/PECAM1+), and (J) a significant presence of macrophages (F4/80+). Representative images for (H, I, J) are shown from C57BL/6J ectopic lesions, and similar staining patterns were observed across all three strains. (K) Quantitative analysis of IHC staining across all ENDO lesions from all strains (n = 3 per group) indicated a high proliferative index (65.18% Ki67+), substantial vascularization (15.68% CD31+), and marked macrophage infiltration (41.67% F4/80+). (Magnification and scale bars to be consistently applied throughout the figure. Example: Magnification = 4x, scale bar = 40 μm; Magnification = 40x, Scale bar = 10 μm).
