AIM:To explore the effect of intravitreal injection FasL inhibitors on corneal apoptosis, Fas, FasL expression, Treg numbers in blood and lymph nodes and rejection index in rats after corneal transplantation.

METHODS:A total of 24 SD rats(24 eyes)who received penetrating keratoplasty were randomly divided into two groups: PBS group received intravitreal injection of PBS(12 rats, 12 eyes)and FasL inhibitor group(12 rats, 12 eyes). Rejection index was recorded every week and blood samples and lymph node were collected at 1, 3 and 5wk after surgery to analyze the proportions of Treg. Corneal tissue was collected for detecting the expression of Fas and FasL and number of apoptosis.

RESULTS: The expression of Fas, FasL in FasL inhibitor group decreased significantly compared with the PBS group(all P<0.05); Corneal cell apoptosis significantly decreased in FasL inhibitor group, and it was the lowest at 5wk after surgery; Treg numbers in blood and lymph nodes significantly increased in FasL inhibitor group at 3wk after surgery(all P<0.05); rejection index of corneal transplantation in the FasL inhibitor group was significantly lower than that of PBS group(all P<0.05).

CONCLUSION:Intravitreal injection of FasL inhibitors after corneal transplantation could reduce the apoptosis in all layers of cornea, increase the number of Tregs in blood and lymph nodes, and alleviate rejection.