G1502

Tissues were fixed with 4% PFA, embedded in paraffin, and sectioned. H&E (G1005, Servicebio, China) and Masson's trichrome (G1006, Servicebio) staining were conducted according to the manufacturer's instructions, respectively. For immunofluorescence analysis, deparaffinized slices were incubated with an Improved Citrate Antigen Retrieval Solution (P0083, Beyotime), and stained with primary antibodies against Sftpc (ab211326, Abcam, USA), Ki67 (GB121141, Servicebio), β‐catenin (8480S, Cell Signaling Technology, USA), and DAPI (C1002, Beyotime). Tunel staining (G1502, Servicebio) was performed according to the manufacturer's instructions. For immunohistochemistry staining of macrophages and neutrophils, deparaffinized slices were incubated with F4/80 (GB113373, Servicebio) and Ly6G (GB11229, Servicebio) antibodies, respectively. For immunocytochemistry analysis, cells were fixed with 4% PFA and stained with primary antibodies against BRACHYURY (ab209665, Abcam) and Oct4 (sc‐5279, Santa Cruz).

Six weeks after myopic induction, three guinea pigs per group were anesthetized intraperitoneally with 4% sodium pentobarbital. The eyes of the guinea pigs were immediately extracted and rinsed in sterile saline to remove the tissue around the eyes. The eyes were fixed in ocular fixative (G1109, Service bio, Wuhan, China) for 24 h, followed by routine dehydration, paraffin embedding, and sectioning. Paraffin sections were then dewaxed, repaired with proteinase K working solution, incubated in an incubator at 37 °C for 22 min, and then washed with PBS. The tissues were covered with a breaking film working solution and incubated at room temperature for 20 min, washed with PBS, and incubated with PBS for 10 min at room temperature, followed by incubation with the TUNEL reaction solution (G1502, Service bio, Wuhan, China) at 37 °C for 2 h. After washing, slides were closed with anti-fluorescence quenching sealer and then observed under a fluorescence microscope (Nikon, Eclipse, Tokyo, Japan). Nuclei in the tissue stained by DAPI are shown in blue, and positive apoptotic nuclei are shown in green.

The TdT-mediated digoxigenin-dUTP nick-end labeling (TUNEL) method was performed using commercially available in situ apoptosis detection kits (11684795910, Roche and G1502, Servicebio) following the manufacturer's protocol. ROS such as superoxide and hydrogen peroxide was detected traditionally by staining techniques according to ROS detection assay (BB-470516, Bestbio).