Allograft survival enhancement using doxycycline in alkali‐burned mouse corneas

Purpose: To explore the inhibitory effects of doxycycline on allograft rejection in alkali‐burned cornea beds. Methods: The corneas of BALB/c mice were injured using a 1 mol/l NaOH solution. Following the injury, the corneas from C57BL/6 mice were transplanted into the eyes of BALB/c mice after being randomized into three groups: allogeneic corneal transplantation (group A), topical use of doxycycline after allogeneic corneal transplantation (group B) and syngeneic corneal transplantation (group C). Corneal angiogenesis was examined using whole‐mount immunofluorescence, and corneal inflammation was evaluated using inflammation index scoring. The immune rejection of the grafts was examined using a slit lamp. In addition, the expression of vascular endothelial growth factor A and interleukin‐1β in the transplanted corneas was examined using a real‐time polymerase chain reaction, immunohistochemistry and an enzyme‐linked immunosorbent assay. Results: The outgrowth of the corneal blood vessels in the group A mice was faster than that in the group B and group C mice. The inflammation index levels were highest in the group A mice, intermediate in the group B mice and lowest in the group C mice. Vascular endothelial growth factor and the interleukin‐1β protein and mRNA levels decreased dramatically in the group B mice compared with the group A mice (all p‐values < 0.01). In addition, the mean survival time in the group B mice (27.00 ± 2.00 days) was significantly longer than that in the group A mice (11.67 ± 1.51 days; p < 0.05). Conclusions: Doxycycline may have had a significant role in preventing corneal angiogenesis and inflammation in alkali‐burned corneal beds, which resulted in higher allograft survival rates.