Objective To identify the distribution of the laminin α5, α2 andγ1 chains within renal basement membrane in Alport syndrome (AS). Methods Kidney tissues from 11 patients of AS, 9 IgA nephropathy (IgAN), 6 focal segmental glomerular sclerosis (FSGS), 5 thin basement membrane disease (TBMD), 6 minor change glomerulonephritis and 3 normal people were examined by immunofluorescence and confocal microscopy for the expression of laminin α5, α2 andγ1 chains. Among 11 Alport patients, 8 male and 2 female patients inherited as X-linked dominant trait and 1 female inherited as dominant trait. The expression of theα3,5 chains of type Ⅳ collagen in GBM were co-absent in all 8 male Alport patients and were partially absent in 2 female patients, whereas their expression were normal in another female patient. Results Laminin α2 chain was deposited in the mesangium and absent from GBM in normal people, but was abnormally deposited in Alport GBM. GBM lamininα2 chain deposition was not observed in IgAN, FSGS, TBMD and minor change glomerulonephritis. As in normal kidney, Alport kidney revealed similar staining for the lamininα5 and γ1 chains. Conclusions Laminin is one of the main components in GBM and mesangium. Abnormal deposition of lamininα2 chain is of clinical importance in AS diagnosis.

Objective To investigate the effect of purified urinary IgG from patients with minimal change nephrotic syndrome and membranous nephropathy on the expression of macrophage migration inhibitory factor (MIF) in human proximal tubular epithelial cells (HK-2). Methods Proteins were precipitated from urine with (NH4)2SO4, and urinary IgG was purified by protein G column chromatography. SDS-PAGE and Western blotting were performed to analyze the urinary IgG. HK-2 cells were incubated with urinary IgG (0,0.5,1.0,2.5,5.0,10.0 mg/ml) from either minimal change nephrotic or membranous nephropathy patients. The expression of MIF mRNA was assessed by RT-PCR, and MIF protein was assessed by Western blotting. Results SDS-PAGE showed that there were four bands, which were all IgG fractions confirmed by Western blotting. The urinary IgG up-regulated the expression of MIF mRNA and protein in HK-2 cells. The expression increased in a dose-dependent manner. The expression of MIF mRNA and protein in HK-2 cells increased significantly when they were incubated with urinary IgG from membranous nephropathy patients at 1mg/ml (P<0.01). However, a dose of 2.5 mg/ml of urinary IgG from minimal change nephrotic patients was required to increase MIF expression. Conclusions The urinary IgG from nephrotic patients with minimal change and membranous nephropathy can up-regulate expression of MIF in HK-2 cells. Compared to the urinary IgG from minimal change nephrotic syndrome, the urinary IgG from membranous nephropathy is more potent to stimulate MIF synthesis in HK-2 cells. These data suggest that structural and functional discrepancies exist between the urinary IgG from minimal change and the one from membranous nephropathy.

Objective To examine the correlation between the components of metabolic syndrome and chronic kidney disease(CKD) including minor renal dysfunction. Methods A retrospective study was performed with 966 patients who had been treated in our Cardiovasology Division,Nephrology Division and Endocrinology Division during 2003. According to the existence of CKD or not, and minor renal dysfunction, these patients were divided into different groups. The correlation between the components of metabolic syndrome and CKD was examined. T test, Chi-square test and Logistic regression were used in the statistic analysis. Results Elevated levels of BMI, serum triglyceride, total cholesterol, uric acid, blood pressure, and plasma glucose were significantly correlated with increased prevalence of both chronic kidney disease and minor renal dysfunction. In addition, low HDL cholesterol level and abdominal obesity were significantly correlated with increased prevalence of chronic kidney disease. The risk increased as a result of a cumulative effect of the components of metabolic syndrome compared with the single component. Hyperglycemia was the most important risk factor for CKD(OR=7.698). Conclusions Metabolic syndrome and its components are important risk factors for CKD and minor renal dysfunction. The risk of chronic kidney disease elevates progressively as the number of components of the metabolic syndrome increases. In addition to hyperglycemia and hypertension, BMI>25 is also an important impact factor among various components.