AIM: To explore the expression and significance of forkhead box class O3(FOXO3)and interleukin-2(IL-2)in conjunctival epithelial cells and tears of patients with dry eye(DE).

METHODS:A perspective study. A total of 106 DE patients who accepted from March 2019 to March 2021 were prospectively gathered, and 85 healthy subjects in the same period were selected as the control group. The level of FOXO3 in the conjunctival epithelial cells and tear fluid was measured by real-time fluorescent quantitative PCR(qRT-PCR)method; The level of IL-2 in the sample was measured by enzyme-linked immunosorbent(ELISA)method; The changes in clinical indicators of the ocular surface such as break-up time(BUT), Schirmer Ⅰtest(SⅠt), cornea fluorescein staining(CFS)in DE patients before and after treatment were analyzed; The correlation between the levels of FOXO3 and IL-2 in the conjunctival epithelial cells and tears of DE patients and the relationship between the two and clinical indicators were analyzed by Pearson correlation analysis.

RESULTS:Compared with the control group, the level of FOXO3 in conjunctival epithelial cells and tear fluid in the DE group was obviously reduced, and the level of IL-2 was obviously increased(all P<0.01). Compared with before treatment, the level of FOXO3 in conjunctival epithelial cells and tear fluid of DE patients was obviously up-regulated, and the level of IL-2 was obviously down-regulated(all P<0.05). Pearson correlation analysis showed that the levels of FOXO3 and IL-2 in conjunctival epithelial cells and tear fluid were obviously inversely correlated(r=-0.531, -0.469, all P<0.01). After treatment, BUT and SⅠt indexes of DE patients increased compared with before treatment, while CFS decreased(all P<0.01). The level of FOXO3 in conjunctival epithelial cells of DE patients was obviously directly correlated with BUT and SⅠt(r=0.431, 0.457, all P<0.01), and it was obviously inversely correlated with CFS(r=-0.469, P<0.01), and the level of IL-2 was obviously inversely correlated with BUT and SⅠt(r=-0.416, -0.447, all P<0.01), and it was obviously directly correlated with CFS(r=0.424, P<0.01); tear FOXO3 was positively correlated with BUT and SⅠt(r=0.421, 0.443, all P<0.01), and it was negatively correlated with CFS(r=-0.474, P<0.01), and IL-2 was negatively correlated with BUT and SⅠt(r=-0.408, -0.429, all P<0.01), and it was positively correlated with CFS(r=0.419, P<0.01).

CONCLUSION: the level of FOXO3 in conjunctival epithelial cells and tears of DE patients is decreased, and the level of IL-2 is increased. The two of which are closely related to the ocular surface indicators of patients. They are expected to become laboratory auxiliary indicators for clinical monitoring and prognostic evaluation of DE.