CXCL8 and keratoconus: Apart from the elements of the proteolytic and fibrinolytic systems, we have examined different cytokines, such as the proinflammatory IL-6 and chemokine CXCL8/IL-8 and the anti-inflammatory Th2 cytokine IL-10 [13]; we found that all of these cytokines cooperate with each other and play a crucial role in the pathogenesis of KC.