关键词: 肾小球肾炎, 膜性；增殖诱导配体；病理状态, 体征和症状

Abstract: Background　Membranous nephropathy，a common cause of nephrotic syndrome in adults，is considered to be an antibody-mediated autoimmune disease.Serum a proliferation-inducing ligand（APRIL） has been shown to be involved in the pathogenesis of a variety of autoimmune diseases，but whether it plays a role in the pathogenesis of idiopathic membranous nephropathy（IMN） is unknown.Objective　To examine the relationships of APRIL level with clinicopathological manifestations，and treatment effect in patients with IMN.Methods　Participants were recruited from The First Affiliated Hospital of Zhengzhou University between February 2015 and February 2016，including 108 with IMN from Department of Nephrology，and 20 sex- and age-matched health examinees from Physical Examination Center.10 ml whole blood sample was collected from IMN patients on the day of undergoing nephrocentesis，and from the controls on the same day.ELISA was used to measure serum APRIL level.By the median APRIL level，IMN patients were stratified into high APRIL expression group（n=54） and low APRIL expression group（n=54）．Clinical and pathological data of IMN patients were collected.A 6-month follow-up was given to the patients，and at the end of which，urinary protein outcome was measured and was used to stratify the patients into responsive and nonresponsive groups.Mean serum APRIL level was compared between IMN and control groups，between high and low APRIL expression groups，and between responsive and nonresponsive groups.Results　The mean serum APRIL level was significantly higher in IMN group compared with that of healthy controls〔（14.3±4.1） μg/L vs（7.7±4.8）μg/L，t=6.383，P<0.001〕.High APRIL expression group showed higher mean serum levels of BUN，Scr，and UA than low APRIL expression group（P<0.05）．What is more，the intensity of IgG deposition in renal specimen significantly increased in high APRIL expression group compared with low APRIL expression group（P<0.05）．Among the 54 patients who completed the follow-up，29 were responsive to the treatment，and other 25 were nonresponsive.However，there was no difference in mean APRIL level between these two groups〔15.7（13.0，17.9）μg/L vs 14.4（11.5，16.5）μg/L，Z=0.950，P=0.327〕.Conclusion　Serum APRIL level was closely associated with the severity of IMN，and was positively correlated with the intensity of deposited IgG in the renal specimen，indicating APRIL may participate in the pathogenesis of IMN.

Key words: Glomerulonephritis, membranous；A proliferation-inducing ligand；Pathological conditions, signs and symptoms