Serum cytokine measurements showed comparable levels of proinflammatory cytokines IL1β, IL-6, TNFα, IL-8 and IFN-γ for 2.II.1 (sample obtained at a time of remission, yet no sample was available during disease activity for comparison) and high levels for 2.III.1 (sample obtained during active keratitis) compared to healthy controls. Here, IL1B is linked to keratitis.