NOS2 and Keratoconjunctivitis sicca: As shown in Figure 9B, we first noted a significant upregulation of M1‐related genes, including NOS2, TNF‐α, and IL‐1β, in SS dry eye patients, whereas no statistically significant differences were observed in the expression of M2 markers, such as Arg1, pointing to M1 macrophage activation in the progression of SS dry eye.