背景:狼疮性肾炎(LN)是一种以针对补体成分的自身抗体为特征的疾病。针对负补体调节因子H(抗FH)的自身抗体在aHUS中普遍存在,与因子H相关蛋白1(FHR1)基因缺失有关,并有明显的功能后果。在C3肾小球疾病中也观察到它们。LN中抗FH的频率和相关性研究甚少。
目的:我们研究的目的是筛选LN患者队列中抗FH和FHR1基因缺失的存在,并评估它们与LN活性的相关性。
方法:采用ELISA和Westernblot检测抗FH和FHR1缺失,分别。通过统计分析处理患者关于抗FH作用的临床和实验室参数。
结果:在少数LN患者中发现了低水平的抗FH-11.7%(7/60),并且与FHR1的缺失无关。抗FH与ANA滴度不相关,抗dsDNA,C3/C4低补体血症,eGFR,蛋白尿,或LN患者的尿沉渣活性。在抗FH和抗C3水平之间发现弱相关性。抗FH与毛细血管内增殖和组织学活性指数相关。根据BILAG肾脏评分,四名抗FH阳性患者患有重度至中度LN。
结论:抗FH自身抗体是LN中的辅助发现,在疾病的活动期更有可能出现。由于它们的低频率和血浆水平,它们似乎不适合LN患者的常规实验室检查.
BACKGROUND: Lupus nephritis (LN) is a disease marked by autoantibodies against complement components. Autoantibodies against negative complement regulator factor H (anti-FH) are prevalent in aHUS, are associated with deletion of factor H-related protein 1 (FHR1) gene, and have overt functional consequences. They are also observed in C3 glomerulopathies. The frequency and relevance of anti-FH in LN are poorly studied.
OBJECTIVE: The aim of our investigation was to screen for the presence of anti-FH and FHR1 gene deletion in a cohort of LN patients and to evaluate their association with LN activity.
METHODS: ELISA test and Western blot for detection of anti-FH and FHR1 deletion were used, respectively. Patients\' clinical and laboratory parameters regarding anti-FH role were processed by statistical analysis.
RESULTS: Anti-FH were found at low level in a small number of LN patients - 11.7% (7/60) and were not associated with deletion of FHR1. Anti-FH did not correlate with ANA titers, anti-dsDNA, C3/C4 hypocomplementemia, eGFR, proteinuria, or active urinary sediment in LN patients. A weak correlation was found between anti-FH and anti-C3 levels. Anti-FH were linked with endocapillary proliferation and histological activity index. Four anti-FH positive patients had severe to moderate LN as per the BILAG renal score.
CONCLUSIONS: Anti-FH autoantibodies are an accessory finding in LN and are more likely to manifest during the active phase of the disease. Due to their low frequency and plasma levels, they do not seem suitable for routine laboratory investigation in patients with LN.