ABSTRACT
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 stage Ⅱ MN 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.
Subject(s)
Humans , Autoantibodies , Clinical Relevance , Colonic Neoplasms , EGF Family of Proteins , Glomerulonephritis, Membranous/diagnosis , Nephrotic Syndrome , Receptors, Phospholipase A2/metabolism , Thrombospondins/metabolismABSTRACT
OBJECTIVES@#To evaluate the value of thrombospond in Type I domain-containing 7A (THSD7A) and M-type phospholipase A2 receptor (PLA2R) in primary membranous nephropathy (PMN) and to explore the relationship between their antibody levels and prognosis.@*METHODS@#Renal tissues in 128 patients with membranous nephropathy in the Second Xiangya Hospital of Central South University were collected from February 2015 to August 2017, including 108 patients with primary membranous nephropathy (PMN group) and 20 patients with secondary membranous nephropathy (SMN) (SMN group). Indirect immunofluorescence method was used to detect the expression of PLA2R antigen in kidney tissues,and the glomerular expression of THSD7A antigen was examined by immunohistochemistry and indirect immunofluorescence. The serum levels of anti-PLA2R antibodies and THSD7A antibodies were also detected by ELISA. According to the results of PMN examination,the patients were also divided into a PLA2R-related membranous nephropathy group and a THSD7A-related membranous nephropathy group.@*RESULTS@#The positive rate of PLA2R in the renal tissues in the PMN group was higher than that in the SMN group (78% in the PMN group, 35% in the SMN group, <0.01),while the positive rate of anti-PLA2R antibody in the PMN group was also higher than that in the SMN group (50% in the PMN group, 25% in the SMN group, <0.05).The serum level of anti-PLA2R antibody was positively correlated with 24 h urine protein (=0.254, <0.05) and negatively correlated with serum albumin (=-0.236, <0.05). The expression of THSD7A was positive in glomeruli in 7 cases of the PMN group (6%) by immuno-histochemistry, and which was positive in 1case of the SMN group (5%).The serum levels of anti-THSD7A antibody in the PMN group were higher than those in the SMN group [(0.49±0.26) pg/mL in the PMN group,(0.34±0.27) pg/mL in the SMN group, <0.05]. There was no difference in the clinical characteristics between the PLA2R-related membranous nephropathy group and the THSD7A-related membranous nephropathy group.@*CONCLUSIONS@#PLA2R and THSD7A are the target antigen of PMN, and the associated autoantibodies are helpful for the differential diagnosis of PMN. The anti-PLA2R antibody levels can reflect the severity of the disease and evaluate the effect of treatment. The incidence of THSD7A membranous nephropathy is low, and monitoring the serum anti-THSD7A antibody levels can assess patients' condition and predict disease outcome.
Subject(s)
Humans , Autoantibodies , Glomerulonephritis, Membranous , Immunohistochemistry , Receptors, Phospholipase A2 , ThrombospondinsABSTRACT
Objective To evaluate the diagnostic value of pathological features of atypical membranous nephropathy (AMN). Methods Ninety - one patients with AMN diagnosed by renal biopsy during 2011 and 2017 were enrolled in this study. On the basis of M - type phospholipase A2 receptor (PLA2R) and thrombospondin type - 1 domain - containing 7A protein (THSD7A) by immunohistochemistry, patients were divided into AMN group (25 cases without PLA2R and THSD7A) and idiopathic membranous nephropathy (IMN) group (66 cases with positive PLA2R or THSD7A). The results of immunofluorescence (IF), light microscopy (LM) and electron microscopy (EM) of these two groups were compared, and the parameters with statistical difference were screened out in order to assess their value in the diagnosis of AMN in fourfold table. Results IF results showed that in AMN group the proportions of IgG deposition on capillary wall and mesangial area as well as positive otherIgG subclasses and complement C1q but negative IgG4 were significantly higher than those in IMN group (respectively, 56.0％ vs 12.1％ , 44.0％ vs 0, both P＜0.05). Their diagnostic specificities for AMN were 87.9％ and 100.0％, respectively. However, the positive rates of IgG accompanied with IgA and/or IgM, predominant IgG4 with other IgG subclasses and complement C1q in two groups were not significantly different (all P＞0.05). LM results showed that the proportions of false double track sign on basement membrane and fuchsinophilic proteins under epithelium, endothelium, basement membrane and mesangial region in AMN group were significantly higher than those in IMN group (respectively, 36.0％ vs 0, 44.0％ vs 1.5％, both P＜0.05). Their diagnostic specificities for AMN were 100.0％ and 98.5％ , respectively. However, the scores of mesangial cell proliferation of these two groups showed no significantly difference (P＞0.05). EM results showed that the rate of endothelial electron dense deposits in AMN group was significantly higher than that in IMN group (36.0％ vs 1.5％, P＜0.05), and its diagnostic specificity for AMN was 98.5％. Conclusions IgG deposition on both capillary wall and mesangial area, positive other IgG subclasses and C1q with negative IgG4, false -double contour sign, multi - site fuchsinophilic deposits and endothelial electron dense deposits may help for the AMN diagnosis in the absence of PLA2R and THSD7A related data.
ABSTRACT
OBJECTIVE: To investigate the clinicopathological features of phospholipase A2 receptor(PLA2R) negative patents with idiopathic membranous nephropathy(IMN). METHODS: IMN patients diagnosed by renal biopsy were enrolled in this study. Glomerular PLA2 R deposition(GAg) and serum anti-PLA2 R antibodies(SAbs) were detected by immunohistochemical staining and enzyme linked immunosorbent assay, respectively. Patients were divided into two groups. Both GAg and SAbs were negative in patients of Group A. Patients of group B were selected from patients who were positive for GAg and SAbs and were matched with group A in gender and age. The clinical and laboratory data of the two groups were collected. Glomerular thrombospondin type-1 domaincontaining 7A(THSD7A) deposition and serum anti-THSD7 A antibody were also measured by immunohistochemical staining and indirect immunofluorescence in the two groups, respectively. RESULTS:(1) Compared with group B, patients in group A had lower levels of proteinuria, lower proportion of microscopic hematuria, higher remission rate(P<0.05). The positive rate of IgG4 in group A(45.0%) was significantly lower than that in group B(85.0%)(P<0.01).(2) The positive rate of glomerular THSD7 A deposition and serum anti-THSD7 A antibody of group A were 17.5% and 7.5%. Patients in group B showed negative THSD7 A tissue staining and antiTHSD7 A antibodies. CONCLUSION: Compared with patients who were positive for GAg and SAbs, patients who were negative for GAg and SAbs exhibited lower levels of proteinuria and higher remission rate. The positive rate of glomerular THSD7 A deposition and serum anti-THSD7 A antibody was low in patients with IMN.
ABSTRACT
After the research of PLA2R1 and its antibodies, Thrombospondin type-1 domain-containing 7A and its antibodies to membranous nephropathy (MN) has made a new understanding.Some researches have reported that the antibodies of PLA2R1 and THSD7A were mutually exclusive in MN, because THSD7A was found in PLA2R1-negative MN patients.But the latest researcher showed that these antibodies can be both positive in MN patients.Similar to the function of PLA2R1, THSD7A can assist clinical diagnosis, treatment, and monitor of MN.In contrast to PLA2R1, THSD7A was also highly expressed on both human and murine podocytes.We can use the mice model to study the pathogenesis of THSD7A-associated MN in the future.In this review, we describe the structure and function of Thrombospondin type-1 domain-containing 7A and its autoantibodies, highlight its role in MN and suggest possible aspects of its future clinical application.
ABSTRACT
Idiopathic membranous nephropathy(IMN) is one of the main pathology of nephrotic syndrome,and has a rising trend year by year.In recent years that IMN is organ specific autoimmune disease.Phospholipase A2 receptor(PLA2R) and thrombospondin type-1 domain containing 7A(THSD7A) are the two main antigens of IMN,which could be used to distinguish the IMN and secondary membranous nephropathy.The anti-PLA2R antibody and anti-THSD7A antibody are associated with diagnosis,severity and activity of the disease.The antibody titer and its change could be used to help deciding the beginning of therapy and the therapitive courses.
ABSTRACT
Objective To analyze the expression of serum anti M phospholipase A2 receptor (PLA2R)antibody in idiopathic membranous nephropathy (IMN),and to investigate its value in the diagnosis and evaluation of idiopathic membranous ne-phropathy.Methods One hundred and eighteen patients with biopsy-proved glomerular diseases were involved in this study, including 97 cases with IMN,21 cases with IgA nephropathy (IgAN)and 19 healthy people.ELISA was used to detect ser-um anti-PLA2R antibodies.Correlations of anti-PLA2R antibody level with laboratory parameters,including serum albumin, 24-hour urine protein of IMN patients were evaluated.Results The median of anti PLA2R antibody in IMN group,IgAN group and healthy group was 45.2(3.6~705.9)RU/ml,5.9(2.3~10.6)RU/ml and 1.2(0.6~9.3)RU/ml.The levels of serum anti PLA2R antibody in IMN group were higher than those in IgA nephropathy group and healthy control group.The difference was statistically significant (t=-5.027,-3.077;P=0.05).Among 97 cases with IMN,76 cases showed posi-tive anti-PLA2R antibodies (positive rate 78.35%).There was none patient showed positive anti-PLA2R antibody respec-tively in IgAN and healthy people.Furthermore,anti-PLA2R antibody level was negatively correlated with serum albumin (r=-0.453,P=0.000)and positively correlated with CREA,TC,ESR,24 hour urine protein (r=0.233,0.234,0.363, 0.586;P=0.004,0.217,0.021,0.000)in IMN patients.Conclusion Serum anti PLA2R antibody may be used as a IMN specific marker for the diagnosis of IMN,and it has important reference value for evaluating the severity of IMN.