| Background and objective: IgA nephropathy (IgAN) is the most common primary glomerular disease in the world and is also one of the important causes of end stage renal failure. 30%-40% patients with IgAN developed end-stage renal disease within 20 years after the diagnosis, which brings heavy burden to family and society. The diagnosis of IgAN still dependent on renal biopsy, However, as renal biopsy is invasive, there are some risks and contraindications for renal biopsy. IgAN's insidious onset easily lead to late treatment. Therefore, early screening, diagnosis and treatment for controlling and reducing the number of patients with ESRD is particularly important. Therefore, it is of great significance to explore the pathogenesis of IgAN and the early noninvasive biomarkers. In this study,Raybiotech cytokine antibody microarray was used to detect the renal tissues of IgAN patients and control group; the urine samples of IgAN patients, idiopathic membranous nephropathy (IMN) patients and normal subjects were compared and analyzed by high-resolution mass spectrometry. The biomarkers of IgAN were screened and their application value was explored to further discuss the potential pathogenesis of IgAN.Methods: (1) 10 patients, 18 to 60 years old, diagnosed as IgAN according to the renal biopsies histology in the PLA General Hospital were chosen, and the renal biopsy was performed to research. A total of 10 cases of renal cell carcinoma in the Department of Urology of General Hospital of Chinese PLA from the age of 18 to 60 years were chosen, and the normal renal tissues 6cm away from cancer tissue were used as controls. Then, collecting the clinical information and laboratory test results of the above population. The renal tissues of these populations were detected by Raybiotech cytokine antibody microarray, the differentially expressed proteins were screened, and the differential proteins were analyzed by GO(Gene Ontology). Based on the results of the analysis, the IL-33 was validated and selected by enzyme linked immune sorbent assay (ELISA).(2 ) Screening patients who were performed renal biopsy in department of Nephrology of Chinese PLA General Hospital. Choosing 48 patients aged 20-60 diagnosed as Lee grade IgAN ? - ?as experience group, 9 patients diagnosed as period IMN ?- ? and also 40 ones aged 20-60 without any basic diseases as control group.Midstream of the first-morning urine from these people were collected. Urine protein in 29 patients with IgAN, 9 patients with IMN and 40 control cases were assayed with Lable free LC/MS. Then, screening out the differential proteins. Finally, analyzing results with GO (Gene Ontology) analysis and pathway enrichment. Based on the data analysis results of LC/MS and the possible pathogenesis of IgAN, transferrin (TF) was tested by enzyme-linked immunosorbent assay (ELISA) in 48 patients with IgAN and normal controls.Results: ( 1 ) A total of 25 differentially expressed proteins were detected between the patients with pathological diagnosis of Lee grade IgAN ?-? and 10 control cases. GO analysis showed that these proteins are related to stress, cell adhesion,protein metabolism and signal transduction. ELISA results determinated that the expression of IL33 in renal tissue of patients with IgAN was significantly higher than that in the control group.(2) Compared with the normal control group, Lable free LC/MS identificated that there were differential expression of 53 proteins between disease group and normal control group (p<0.05). There were differential expression of 15 proteins between IMN group and normal control group, but there is no difference between IgAN group and normal group (p<0.05). There were differential expression of 13 proteins between IgAN group and normal control group, but there is no difference between IMN group and normal control group (p<0.05). Between IMN group and IgAN group,there were 9 proteins differentially expressed. GO analysis showed that these proteins are involved in blood coagulation and thrombosis, inflammation, complement system activation, protein transport, iron metabolism, glucose metabolic process and lipid transport. The expression of C3, EGF and APOD were consistent with previous studies. ORM1 and ORM2 may be biomarkers for diagnosis of IgAN and IMN. The results of ELISA showed that the expression level of TF in urine of patients with IgAN was significantly higher than that in normal control group. This result indicated that it would be of large diagnostic value of TF for IgAN diagnostic.Conclusions: IL-33 is associated with the pathogenesis of IgAN. TF may be superior marker to 24h urinary protein in the early diagnosis of IgAN and IMN. The high concentration level of ORM1 and ORM2, especially ORM2, in the urine of patients with IgAN may be an important marker of distinguishing IMN and IgAN. CETP may be a biomarker for the diagnosis of IgAN. |
PDF Full Text Request