60000SSA抗原第230-241表位在系统性红斑狼疮中性粒细胞上的表达及意义

The preliminary investigation on the expression and clinical significance of epitope 230-241 of SSA antigen on the neutrophils of systemic lupus erythematosus

目的通过对伴中性粒细胞减少的系统性红斑狼疮（SLE）患者周围血中性粒细胞60000SSA抗原第230-241表位表达水平的检测，并与相关的临床指标分析比较，初步探讨这一表达的临床意义。方法用人工合成的60000SSA抗原第230-241表位（E230-241）寡肽，从课题组已成功构建的SSA噬菌体单链可变区（scFv）抗体库中筛选得相应的scFv单抗，用其标记18例伴粒细胞减少的SLE患者和10名正常人周围血中性粒细胞，流式细胞仪比较检测E230-241的表达程度．分析其与中性粒细胞计数、SLE病情活动指数（SLEDAI）、总病程、病情活动时间之间的关系，并比较重症和轻症SLE患者间这一表达程度的差别。结果SLE组患者E230-241的表达明显高于正常人（20±12 VS 7±5，P=0.001）。且表达程度与粒细胞计数呈负相关（r=-0.686，P=0.002），与SLEDAI呈正相关（r=0．665，P=0．003），与病情活动时间呈正相关（r=0．571，P=0．013），与总病程无显著相关性（r=0．114，P=0．651）；重症患者的表达程度明显高于病情相对较轻者（31±10 VS 12±8,P=0．001）。结论SLE患者周围血中性粒细胞增强表达E230-241,可能是其粒细胞减少的原因之一。并可能参与SLE其他系统的损害。

Objective To investigate preliminarily the clinical significance of the expression of epitope230-241 （E230-241）, one of the 20 epitopes of 60000 SSA antigen, on peripheral neutrophils by examing its expression and assessment of its association with clinical data in systemic lupus erythematosus （SLE） patients with neutropenia. Methods The single-chain fragment V （scFv） monoclone antibody （mAb） against E230- 241 was obtained from the SSA phagemid antibody library. It was constructed successfully and E230-241 oligopeptide was synthesized according to the amino acid sequence of 230 to 240 of 60 000 SSA antigen. Peripheral neutrophils were collected from 18 SLE patients with neutropenia and 10 normal eontrols. The expression of E230-241 on these neutrophils were assessed by flow cytometry using the scFv mAb against E230-241. Correlative analyses was employed to detect the relationship between the E230-241 expression and the neutrophil counts, SLE disease activity index （SLEDAI）, total course of SLE as well as the interval period between episodes of disease flares. The expression in patients with severe clinical condition was also compared with those with mild disease. Results The E230-241 expression in SLE group was more evident than controls （20±12 vs 7±5, P=0.001）. The level of expression was not only inversely correlated with neutrophil counts （r=-0.686, P=0.002）, but also positively correlated with SLEDAI （r=0.665, P=0.003） and the interval period between episodes of disease flare （r=0.571, P=0.013）. No association between the expression and the total course of SLE （r=0.114, P=0.651 ） was found. The patients with severe disease had significantly higher level of expression of E230-241 on their neutrophils than those with mild to moderate disease. Conclusion The enhanced expression of E230-241 on peripheral neutrophils in SLE may be one of the most important causes of neutrooenia.