In a previous study of our research group, increased nuclear factor kappa B p65 (NF-κB) mRNA and protein expression, and an increased inducible NO synthase (iNOS) mRNA expression could be verified in human keratoconus fibroblasts (KC-HCFs), compared to healthy controls, which refers to corneal inflammation in KC [6]. Here, NOS2 is linked to keratoconus.