抗中性粒细胞胞质抗体的检出率及其靶抗原研究

Detectable rate and target antigens of antineutrophil cytoplasmic antibodies in Chinese patients with clinically suspected small vessel vasculitis

目的 了解抗中性粒细胞胞质抗体 (ANCA)阳性检出率、流行病学特点及其靶抗原。方法 应用间接免疫荧光法 (IIF)、抗髓过氧化物酶 (MPO)和抗蛋白酶 3(PR3)酶联免疫吸附试验(ELISA)对近年送检的怀疑小血管炎的 5 6 0 4例患者血清进行了检测 ,对IIF ANCA阳性而抗MPO和抗PR3抗体均阴性的血清还进行了其他 5种ANCA特异性靶抗原的检测。并初步对ANCA阳性患者流行病学特点进行分析。结果 IIF ANCA检出率为 5 3% ,阳性检出最多在 7、8及 12月份。另外所有血清中有 390例 (7% )ANA阳性。所有血清进行抗MPO和抗PR3 ELISA检测 ,抗MPO抗体阳性 2 13例 ,抗PR3抗体阳性 32例 ,两者同时阳性 5例。 4 8例不识别MPO和PR3而IIF法阳性的血清中 13例识别其他已知靶抗原 ,识别杀菌 /通透性增高蛋白 (BPI)、人弹力蛋白酶 (HLE)、组蛋白酶G (CG)、天青杀素 (AZU)和乳铁蛋白 (LF)等靶抗原的血清分别为 7、5、1、1、0例 ,其中 1例为抗BPI和抗HLE ANCA同时阳性。 85 %的IIF ANCA阳性患者确诊为ANCA相关小血管炎。这些患者中 ,抗MPO和抗PR3的比例约为 7∶1:男女比例为 1∶1 12 ,年龄 7～ 79岁 ,平均 5 3 1岁 ,>6 0岁的老年人男女比例为 1 17∶1,而年龄 <2 0岁患者男女比例为 1∶4。结论 ANCA相关疾病在我国并不少见 ,以IIF法检?

Objective To study the detectable rate of antineutrophil cytoplasmic antibodies (ANCA) in Chinese patients with clinical suspected small vessel vasculitis,and the target antigens.Methods All 5 604 sera sent to the authors′ laboratory for ANCA screening were tested by indirect immunofluorescence (IIF),anti myeloperoxidase (MPO),and anti proteinase 3 (PR3) ELISA.Then the positive sera with IIF ANCA but negetive with MPO and PR3 ANCA were further tested by antigen sepecific ELISA using other five highly purified known ANCA antigens as solidphase ligands.The known antigens included human leukocyte elastase (HLE),lactoferrin (LF),cathepsin G (CG),bactericidal/permeability increasing protein (BPI) and azurocidin (AZU).Results Of the 5 604 sera,298(5 3%) were IIF ANCA positive,and 390/5 604(7%) were ANA positive.Patients′ANCA presented mainly in summer or winter.Of the IIF ANCA positive patients,213 were anti MPO positive,32 were anti PR3 positive and 5 were positive for both.Of the 48 sera positive by IIF,yet negative by MPO and PR3 ANCA,13 sera(27%) recognized other target antigens,7 sera recognized BPI,5 recognized HLE,one recognized CG and one recognized AZU,and none of the sera recognized LF.One serum recognized both BPI and HLE.There was no difference in gender(M∶F=1∶1 12) in ANCA positive patient with a mean age of 53 1 years.However,the M/F ratio was 1 17∶1 for patients over 60 years,and was 1∶4 for patients less than 20 years.Conclusion ANCA related diseases are not rare in China and the major antigens are MPO and PR3.When IIF technique is used to detect ANCA,ANA should be carefully distinguished.Some sera also recognized other known ANCA antigens,but for a few sera the target ANCA antigens are still unkown.