Fig 2: The expression of FSTL1, TGFβ, CTGF, VEGF, FN, COL1 and α-SMA in HRCECs. In Immunofluorescence figures, (A) indicates normal cell fluorescence, hypoxic 3 h cell fluorescence and hypoxic 6 h cell fluorescence (10×). (B–H) indicates the quantitative analysis of immunofluorescence figures in the normal, 3 h hypoxia, and 6 h hypoxia models using ImageJ. The 3 h and 6 h hypoxia results indicated that FSTL1, TGFβ1, CTGF, VEGF, FN, COL1, and α-SMA were expressed at significantly higher levels than in normal cells. (I–O) indicates that the mRNA expression of FSTL1 and ECM-related factors in the three models. The expression of FSTL1, TGFβ1, CTGF, VEGF, FN, COL1, and α-SMA mRNA in 3 h and 6 h hypoxia conditions, respectively, were expressed at significantly higher levels than in normal cells (N: normal, h3: 3 h hypoxia, h6: 6 h hypoxia). Data are expressed as mean ± SEM. * means P < 0.05, **means P < 0.01, *** means P < 0.001.

Fig 3: Stronger FSTL1 staining and weaker VEGF staining in the IVB-treated membranes. (A) FSTL1 and VEGF proliferative membrane immunofluorescence results in PDR patients with and without anti-VEGF treatment. Vimentin, as an internal reference. DAPI, the tracer shows the nuclear position of the fluorescent agent 4',6-diamidino-2-phenylindole (magnification: ×10). (B) The levels of FSTL1 and VEGF were analyzed using ImageJ. Stronger FSTL1 staining was detected in the IVB-treated membranes than in the untreated membranes, and VEGF staining was weaker in the IVB-treated group than in the untreated group. Data are expressed as mean ± SEM. * means P < 0.05, **means P < 0.01, *** means P < 0.001.

Fig 4: The expression of FSTL1, TGFβ, CTGF, VEGF, FN, COL1, and α-SMA proteins in HRCECs. (A) shows western blots representatives of FSTL1, TGFβ, CTGF, VEGF, FN, COL1, α-SMA and β-actin in HRCECs. (B–H) shows the ratio of FSTL1, TGFβ, CTGF, VEGF, FN, COL1, and α-SMA to β-actin in the hypoxic treated HRCECs and normal controls, respectively. Indicates the quantitative analysis of western blots figures in the normal, 3 h hypoxia, and 6 h hypoxia models using ImageJ. The 3 h and 6 h hypoxia results indicated that FSTL1, TGFβ, CTGF, VEGF, FN, COL1, and α-SMA were expressed at significantly higher levels than in normal cells (N: normal, h3: 3 h hypoxia, h6: 6 h hypoxia). Data are expressed as mean ± SEM. * P < 0.05, ** P < 0.01, *** P < 0.001.

Fig 5: FSTL1 expressed higher in vitreous humor in the anti-VEGF-treated PDR patients. The level of FSTL1 expression in vitreous humor was significantly higher in the anti-VEGF-treated PDR patients than in the untreated PDR patients. Data are expressed as mean ± SEM. * means P < 0.05, **means P < 0.01, *** means P < 0.001.