Effects of IDO on the inflammatory response of A. fumigatus keratitis. The corneas of C57BL/6 mice were inoculated with A. fumigatus. The corneas were monitored, photographed under a slit lamp microscope (A–D), and evaluated using the scoring system (E). On the third day after A. fumigatus infection, the severity of corneal disease in the 1-MT+A.F. group (D) was found to be worse than that in the A.F. group (C), although there was no obvious inflammation in the corneas of the 1-MT group (B), compared with the control group (A). The clinical score of the 1-MT+A.F. group was higher than that of A.F. group (P < 0.01), and there was no significant difference between the 1-MT group and the control group (E).