The Relationship Between Serum Anti-PLA2R Antibody And Glomerular PLA2R Antigen In The Clinicopathology Of Idiopathic Membranous Nephropathy

Objective : To further appraise the clinicopathological significance of serum anti-PLA2 R antibody and glomerular PLA2 R antigen in idiopathic membranous nephropathy and the possible correlation between this two factors.Methods : 122 cases of IMN patients diagnosed by renal biopsy and clinical data were enrolled and they all did not have a history of hormones and immunosuppressive agents before renal biopsy.serum anti-PLA2 R antibody and glomerular PLA2 R antigen were detected by enzyme-linked immunosorbent assay and indirect immunofluorescence respectly.Simultaneously,their clinical and laboratory results were collected.27 cases were selected from patients who were diagnosed as membranous nephropathy by renal biopsy and their serum anti-THSD7 A antibody and serum anti-PLA2 R antibody were measured by ELISA.Results :1.In 122 patients with IMN,the positive rate of S-PLA2 R and G-PLA2 R were77.9% and 92.6%,respectively.The proportion of patients in G-PLA2 R positive group was significantly higher than that in S-PLA2 R positive group(P=0.001).2.Compared with the S-PLA2 R negtive group,S-PLA2 R positive group showed lower serum albumin levels,more severe proteinuria,lower IgG levels,and higher lipid levels,with a larger proportion of male patients and more nephrotic syndromes.3.The positive rate and intensity of PLA2R?the positive rate of IgG1 and the early stage of the Membranous nephropathy in the S-PLA2 R positive group and the S-PLA2 R negative group were significantly different.4.Compared with the G-PLA2 R negative group,the G-PLA2 R positvve group showed higher serum anti-PLA2 R antibody positive rate and higher serum anti-PLA2 R antibody titer,but there were no differences in clinical indicator ssuch as serum albumin,proteinuria renal function,eGFR,etc.5.In terms of pathology,G-PLA2 R negative group have more patients in the earlystage of membranous nephropathy,and no significant difference is detected in deposition of IgG1,IgG4,C3 and C1 q in the two groups.6.With the increase of serum anti-PLA2 R antibody titer,the positive rate and intensity of tissue PLA2 R,IgG1,IgG4,C3,and membrane stage and segmental sclerosis did not show linear changes.7.As the intensity of PLA2 R deposition in renal tissue increased,serum anti-PLA2 R antibody levels increased first and then decreased.8.In 6 cases of IMN patients with negative S-PLA2 R and G-PLA2 R,the expression of glomerular THSD7 A antigen was negative.Among the 23 patients with IMN,1(4.3%)was positive for anti-THSD7 A antibody and anti-PLA2 R antibody.Conclusion :Renal tissue PLA2 R antigen is more sensitive in the diagnosis of idiopathic membranous nephropathy.Combining serum anti-PLA2 R antibody and renal tissue PLA2 R antigen will greatly improve the diagnosis rate of idiopathic membranous nephropathy.Serum anti-PLA2 R antibodies are more likely to reflect the severity and activity of the disease than the renal tissue PLA2 R antigen.Patients with negative serum anti-PLA2 R antibody or patients with negative PLA2 R in renal tissue were more likely to be in the early stage of membranous nephropathy,and there was no significant correlation between membrane staging and onset time.With the increase of serum anti-PLA2 R antibody titer,the positive rate and intensity of PLA2 R antigen,the positive rate and intensity of IgG subtypes(IgG1 and IgG4)and other pathological parameters did not show obvious linear trend.Serum anti-PLA2 R antibody levels showed a trend of increasing first and then decreasing as the intensity of PLA2 R antigen in kidney tissue increased.The incidence of THSD7A-associated membranous nephropathy is low in Chinese patients,and anti-THSD7 A antibodies may play an important role in reflecting the severity of IMN and predicting prognosis.