Anti-C1q antibodies and IgG subclass distribution in sera from Chinese patients with lupus nephritis
Anti-C1q antibodies and IgG subclass distribution in sera from Chinese patients with lupus nephritis
复制标题
DOI：
10.1093/ndt/gfn453
复制
发表时间：
2009-01-01
影响因子：
6.1
通讯作者：
Zhao, Ming-hui
中科院分区：
文献类型：
--
作者：
Fang, Qi-Ying;Yu, Feng;Zhao, Ming-hui
客观的。抗 C1q 抗体在狼疮性肾炎 (LN) 患者的血清中很常见，并且与疾病活动性相关。本研究旨在进一步探讨LN患者血清IgG抗C1q抗体的患病率、其亚类分布及其临床病理关联。方法。血清采集自2000年至2006年在我院诊断的150例经肾活检证实的LN患者、30例无肾脏受累临床证据的系统性红斑狼疮(SLE)患者(非肾性SLE、NR-SLE)和63名健康供者。采用ELISA法检测血清IgG抗C1q抗体及其亚类。进一步分析了它们的临床和病理关联。结果。 LN 中 IgG 抗 C1q 抗体的患病率（84/150，56%）显着高于 NR-SLE（6/30，20%）和健康对照（3/63，4.8%）（分别为 P < 0.005、P < 0.001）。弥漫性增生性肾病灶（IV级）患者抗C1q抗体检出率（59/82，71.95%）显着高于非弥漫性增生性肾病灶（II+III级）（12/26，46.15%，P=0.016）和V级（13/42，30.95%，P<0.001）。 IgG2（60/135，44.44％）的患病率显着高于IgG1（37/135，27.41％）和IgG3（25/135，18.52％）（分别P <0.005，P <0.001）。 IgG2与关节炎的发生（P < 0.05）、较高的血清肌酐（P < 0.05）和较低的血清C3（P < 0.05）相关。 38例LN患者活动期和缓解期血清中，活动期抗C1q抗体阳性17例，缓解期抗体水平全部下降，9例（52.94%）转为阴性。同时，IgG1、IgG2和IgG3抗C1q转阴比例分别为33%（2/6）、53.85%（7/13）和100%（7/7）。结论。抗 C1q 抗体在 LN 中普遍存在，与弥漫性增殖性病变密切相关。 IgG2 抗 C1q 可能具有致病性，而 IgG3 抗 C1q 可能是监测疾病活动性的更特异的生物标志物。
Objective. Anti-C1q antibodies are common in sera from patients with lupus nephritis (LN) and are associated with disease activity. The current study aimed to further investigate the prevalence of serum IgG anti-C1q antibody, its subclass distribution and their clinical and pathological association in patients with LN.Methods. Sera were collected from 150 patients with renal biopsy-proven LN, diagnosed from 2000 to 2006 in our hospital, 30 patients with systemic lupus erythematosus (SLE) without clinical evidence of renal involvement (non-renal SLE, NR-SLE) and 63 healthy donors. ELISA was used to detect serum IgG anti-C1q antibody and its subclass. Their clinical and pathological associations were further analysed.Results. The prevalence of IgG anti-C1q antibody in LN (84/150, 56%) was significantly higher than that in NR-SLE (6/30, 20%) and healthy controls (3/63, 4.8%) (P < 0.005, P < 0.001, respectively). The prevalence of anti-C1q antibody in patients with diffuse proliferative renal lesions (class IV) (59/82, 71.95%) was significantly higher than that in those with non-diffuse proliferative renal lesions (class II + III) (12/26, 46.15%, P = 0.016) and class V (13/42, 30.95%, P < 0.001). The prevalence of IgG2 (60/135, 44.44%) was significantly higher than that of IgG1 (37/135, 27.41%) and IgG3 (25/135, 18.52%) (P < 0.005, P < 0.001, respectively). IgG2 was associated with the occurrence of arthritis (P < 0.05), higher serum creatinine (P < 0.05) and lower serum C3 (P < 0.05). Of the 38 LN patients with sera both in active phase and in remission, 17 were anti-C1q antibody-positive in active phase and the antibody levels decreased in all and turned to negative in 9 (52.94%) in remission. Meanwhile, the ratio of turning negative of IgG1, IgG2 and IgG3 anti-C1q was 33%(2/6), 53.85% (7/13) and 100% (7/7), respectively.Conclusions. Anti-C1q antibodies are prevalent in LN and are closely associated with diffuse proliferative lesions. IgG2 anti-C1q might be pathogenic and IgG3 anti-C1q might be a more specific biomarker for monitoring disease activity.