Pre-treatment with EGCG reduced the secretion of IL-6 in IL-1β-treated orbital fibroblasts slightly, in all patients with non-TAO (reduction level: range: 3.7–17.0%, mean: 11.4%, Fig 1B) and two patients with TAO (reduction level: 3.8% in #53 and 15.2% in #58)(Fig 1A), whereas a significant inhibitory effect of EGCG on IL-6 secretion was observed in orbital fibroblasts form two TAO patients (reduction level: 60.0% in #55 and 75.9% in #59)(Fig 1A). Here, IL1B is linked to thromboangiitis obliterans.