CXCR2 expression on neutrophils is upregulated during the relapsing phase of ocular Behcet disease

Purpose: To search for markers of Behcet disease (BD) activity, we measured CXCR1 and CXCR2 levels on the circulating leukocytes of patients suffering from ocular BD. Methods: Peripheral blood leukocytes were harvested from healthy volunteers (n = 16) and ocular BD patients (n = 35). The patients consisted of 15 individuals in relapsing phase (6 with prednisolone treatment) and 20 individuals in remission phase (9 with prednisolone treatment). Expression of CXC chemokine receptors (CXCRs) on leukocytes (including lymphocytes, monocytes, neutrophils) was measured using flow cytometry. Results: Without prednisolone treatment, CXCR2 expression (on both total leukocytes and neutrophils) in relapsing phase was significantly higher than in remission-phase patients or normal individuals. By contrast, no significant difference was detected in the expression of CXCR1 between any of the groups. Importantly, low-dose prednisolone therapy reduced CXCR2 expression on neutrophils. Conclusions: CXCR2 has a potential role in promoting uveitis during ocular attack and might also be a useful marker for disease activity.