结缔组织病相关肺动脉高压抗内皮细胞抗体检测及其靶抗原研究

Specific anti-moesin antibodies could be detected in patients with pulmonary arterial hypertension associated with connective tissue diseases

目的 检测抗内皮细胞抗体（AECA）在结缔组织病（CTD）相关肺动脉高压（PAH）患者中的阳性率,探讨其可能的致病机制.方法 试验组选取68例CTD相关PAH患者,对照组为12例特发性肺动脉高压患者、61例CTD无PAH的患者、20例慢性阻塞性肺疾病合并肺源性心脏病患者及20名健康人.提取EA.hy926内皮细胞株的膜蛋白质,免疫印迹法检测以上各组患者血清中AECA阳性率,采用X2检验确定特异性的条带.进而应用液相色谱-电喷雾离子阱质谱分析,分离和鉴定AECA特定的靶抗原.结果免疫印迹法检测结果显示,AECA-78 000条带的阳性率在CTD相关PAH患者79%（54/68）和CTD合并肾小球病变的患者71%（15/21）,明显高于特发性PAH患者8%（1/12）、CTD无内脏受累患者50%（10/20）、CTD单纯合并肺间质纤维化患者15%（3/20）和健康对照组（P〈0.05或P〈0.01）.经蛋白质组学方法 分离鉴定,AECA-78 000的靶抗原成分为膜突蛋白.结论 CTD不同靶器官受累的患者AECA78 000条带的阳性率不同,CTD合并PAH患者和CTD合并肾小球病变的患者可能存在有共同的靶抗原（78 000内皮细胞蛋白质）,其成分为膜突蛋白.

Objective To detect the positive rate of anti-endothelial cell antibody （AECA） in patients with pulmonary arterial hypertension （PAH） associated with connective tissue diseases（CTD）and to investigate the specific target antigen.Methods Sera of 68 patients with CTD associated PAH were collected to detect AECA by Western blotting with extracted membrane protein of the endothelial cell line EA.hy926.Sera of 61 CTD patients without PAH,20 with idiopathic pulmonary arterial hypertension（IPAH）,20 with chronic obstructive pulmonary diseases and pulmonary arterial hypertension （COPD-PAH） and 20 healthy donors were collected as controls.The correlation between PAH and specific bands of AECA was studied by X2 test.Liquid chromatography-electrospray ionization mass spectrography was used to detect the target antigens related to PAH associated with CTD.Results The specific molecular size of antigen was 78 000.The AECA-78 000positive rate of CTD patients with PAH was 79% （54/68）.not significantly ditierent from that of CTD with glomerulonephritis（71%,15/21）,but significantly higher than those of CTD with interstitial lung disease （ILD）（15%,3/20）and CTD without systemic involvement（P〈0.01 and P〈0.05 respectively）.also higher than those of IPAH（8%,1/12）.The AECA-78 000 was negative in COPD-PAH and healthy controls.The target antigen of AECA-78 000 was identified by proteomic techniques as moesin.Conclusion CTD patients with different target organ involvement have different AECA-78 000 positive rates,which could be frequently detected in CTD associated PAH and those with glomerulonephritis.The common antigen is moesin.