,36 Therefore, in this study, the authors used LOCS III to classify cataract disease severity, and the authors found that the level of PEDF was negatively correlated with LOCS III classification, and the levels of MMP-2 and TGF-β2 were positively correlated with LOCS III classification, suggesting that changes in the levels of the above indexes may be related to disease severity. Here, MMP2 is linked to cataract.