肾组织血小板反应蛋白1型结构7A域及神经表皮生长因子样蛋白-1 检测在M型磷脂酶A2受体阴性膜性肾病中的临床意义

Clinical Significance of Thrombospondin Type 1 Domain-Containing 7A and Neural Epidermal Growth Factor-Like 1 Protein in M-Type Phospholipase A2 Receptor-Negative Membranous Nephropathy

目的探讨肾组织血小板反应蛋白1型结构7A域(THSD7A)及神经表皮生长因子样蛋白-1(NELL1)检测在M型磷脂酶A2受体(PLA2R)阴性膜性肾病中的诊断及治疗指导意义。方法选取浙江中医药大学附属杭州市中医院2014至2021年肾穿刺活检确诊为PLA2R阴性膜性肾病共116例,通过免疫组织化学方法检测肾组织THSD7A及NELL1的阳性表达情况,比较各组间临床病理特征及治疗与预后。结果116例PLA2R阴性膜性肾病中THSD7A阳性23例,NELL1阳性9例,其中两者双阳性1例。THSD7A阳性较阴性者IgG4阳性率更高(P=0.010);膜性肾病Ⅰ期占比更少,Ⅱ期占比更多(P=0.002);基底膜增厚更明显(P=0.034)。NELL1阳性较阴性者C1q及IgG2的阳性率更低(P=0.029,P=0.001);炎细胞浸润更多(P=0.033);多部位沉积物更少(P=0.001);基底膜增厚更不明显(P<0.001);不典型膜性肾病比例更低(P=0.010)。继发因素分析显示THSD7A阳性者有1例确诊为乙状结肠癌,NELL1阳性者均未发现恶性肿瘤。生存分析提示THSD7A阳性组肾病复合缓解率(完全缓解或部分缓解)显著低于阴性组(P=0.016),而NELL1阳性组肾病复合缓解率显著优于阴性组(P=0.015),两指标单一阳性组间比较显示NELL1单一阳性组肾病复合缓解率显著优于THSD7A单一阳性组(P<0.001)。结论THSD7A及NELL1阳性膜性肾病更倾向于原发性膜性肾病,且无恶性肿瘤提示价值,但对膜性肾病患者的预后具有一定的预测价值。

Objective To investigate the clinical significance of thrombospondin type 1 domain-containing 7A(THSD7A)and neural epidermal growth factor-like 1 protein(NELL1)in phospholipase A2 receptor(PLA2R)-negative membranous nephropathy(MN).Methods A total of 116 PLA2R-negative MN patients treated in Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University from 2014 to 2021 were enrolled in this study.Immunohistochemistry was employed to detect THSD7A and NELL1 in the renal tissue.The pathological characteristics,treatment,and prognosis were compared between positive and negative groups.Results The 116 PLA2R-negative MN patients included 23 THSD7A-positive patients and 9 NELL1-positive patients.One patient was tested positive for both proteins.The THSD7A-positive group showed higher positive rate of IgG4(P=0.010),more obvious glomerular basement membrane(GBM)thickening(P=0.034),and higher proportion of stageⅡMN and lower proportion of stage I MN(P=0.002)than the THSD7A-negative group.The NELL1-positive group had lower positive rates of C1q and IgG2(P=0.029,P=0.001),less obvious GBM thickening(P<0.001),more extensive inflammatory cell infiltration(P=0.033),lower proportion of deposits on multi-locations(P=0.001),and lower proportion of atypical MN(P=0.010)than the NELL1-negative group.One patient with THSD7A-positive MN was diagnosed with colon cancer,while none of the NELL1-positive patients had malignancy.Survival analysis suggested that THSD7A-positive MN had worse composite remission(either complete remission or partial remission)of nephrotic syndrome than the negative group(P=0.016),whereas NELL1-positive MN exhibited better composite remission of nephrotic syndrome than the negative group(P=0.015).The MN patients only positive for NELL1 showed better composite remission of nephrotic syndrome than the MN patients only positive for THSD7A(P<0.001).Conclusions THSD7A-and NELL1-positive MN is more likely to be primary MN,and there is no significant malignancy indication.However,it might have a predictive value for the prognosis of MN.