CXCL8 and thromboangiitis obliterans: However, the levels of IL-1β-induced IL-8 secretion varied depending on the strains of orbital fibroblasts from TAO (range: 35,430–48,770 pg/ml, mean: 43,402 pg/ml) and non-TAO patients (range: 26,805–46,872 pg/ml, mean: 37,885 pg/ml) (Fig 2).