Of note, most of these investigations have compared active with inactive uveitis or a healthy control group showing increased serum levels of different cytokines in the active group, such as the IL-8 [39,40], IL-6 [39], TNF-α [41], IL-17 [42], IL-21 [43], IL-23 [42,44]. Here, CXCL8 is linked to uveitis.