To analyze the effect of riboflavin UV-A illumination on mRNA and protein expression of healthy (HCFs) and keratoconus human corneal fibroblasts (KC-HCFs), concerning the inflammatory markers NF-κB, iNOS, IL-6, and collagen 1 and 5 (Col 1/Col 5). This evidence concerns the gene NOS2 and keratoconus.