bromochloroacetic-acid and Glomerulosclerosis--Focal-Segmental

A link between the number of podocytes excreted in the urine and activity of glomerular disease has been established. The aim of this study was to investigate possible correlations between urinary cells' phenotype and the progression of focal segmental glomerulosclerosis (FSGS).. Forty patients with newly diagnosed FSGS were included. Cells were isolated from urine by adherence to collagen-coated cover slips and assessed for the expression of podocalyxin (PDX), CD68 and Ki67 antigens by indirect immunofluorescence. In addition, double-staining procedures were performed in combinations of the above antigens plus cytokeratin, WT1 and CD-105. Twenty-two patients in whom urinary protein to creatinine ratio exceeded 2.0 at diagnosis were followed for 36 months, with assessments of renal function and proteinuria every 3 months. During observation, patients were subjected to standard therapy.. Significantly higher numbers of Ki67 positive cells at the onset of the study were observed in patients who have doubled serum creatinine (SCr) in follow-up, than in those who have not (p = 0.0149). By logistic regression analysis, both CD68 and Ki67, but not anti-PDX positive cell numbers at diagnosis were found to be predictors of doubling SCr concentration in 36 months' follow-up. Results of double staining indicate that PDX positive cells could be identified as podocytes or their precursors and parietal epithelial cells.. Urinary sediment PDX positive cell numbers do not predict the progression of FSGS, whereas CD68 and Ki67 phenotype of urinary podocytic lineage clearly has a prognostic significance in 36 months' observation of primary FSGS.

Topics: Adult; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Creatinine; Disease Progression; Endoglin; Female; Follow-Up Studies; Glomerulosclerosis, Focal Segmental; Humans; Keratins; Ki-67 Antigen; Male; Middle Aged; Podocytes; Predictive Value of Tests; Proteinuria; Receptors, Cell Surface; Sialoglycoproteins; Urine; WT1 Proteins

The detection of viable podocytes in the urine of patients with proteinuric diseases has been described as a non-invasive method to monitor disease activity. Most of the published studies use podocalyxin (PDX) as a podocyte specific marker.. We examined the excretion of viable PDX-positive cells in a random set of spot urine from patients with biopsy-proven focal segmental glomerulosclerosis (FSGS), membranous nephropathy (MGN) or membranoproliferative glomerulonephritis (MPGN) and characterized the excreted cells for podocyte and parietal epithelia markers as well as for proliferation activity.. We found that untreated patients with active disease excrete high numbers of PDX-positive cells in their urine. In contrast to that we were not able to detect significant amounts of PDX-positive cells in the urine of patients with active minimal change disease (MCD) and patients with FSGS or MGN in full remission. When we further characterized the cells we rarely detected expression of podocyte specific markers in the PDX-positive cells, but at least 50% of the PDX-positive cells were double positive for cytokeratin (CK8-18). Immunohistochemistry of the corresponding renal biopsies showed that 100% of podocytes and parietal cells stained positive for PDX. Semiquantitative analysis revealed that 45% of parietal cells were positive for CK8-18 and 100% of proximal tubular cells. No cells of the glomerular epithelial layer stained positive for CK8-18.. PDX-positive cells are lost in the urine in disease states that require podocyte regeneration and are a useful non-invasive marker for glomerular disease activity. These cells are possibly derived from the parietal epithelial layer.

Topics: Adolescent; Adult; Aged; Case-Control Studies; Child; Child, Preschool; Female; Glomerulonephritis, Membranoproliferative; Glomerulonephritis, Membranous; Glomerulosclerosis, Focal Segmental; Humans; Keratins; Kidney; Male; Middle Aged; Podocytes; Sialoglycoproteins; Staining and Labeling; Urine; Young Adult

WT1 and Pax2 are transcription factors involved in kidney development and phenotypic regulation of glomerular epithelial cells. In primary focal segmental glomerulosclerosis (FSGS), the alteration of the podocyte is important for the development of the cellular lesion (CL) and glomerular scar formation. To investigate the contribution of WT1 and Pax2 to the development of the CL in primary FSGS, immunohistological studies were performed using renal biopsy specimens on the expression of WT1, Pax2 and cytokeratin (CK), which is an epithelial marker but never found in normal podocytes. The expression of WT1 was decreased in the CL compared with unaffected podocytes, but Pax2 and CK were expressed significantly in the CL and also in the cells morphologically recognized as podocytes in cases with CL. Our results suggest that re-expression of Pax2 resulting in phenotypic change of podocytes to a different epithelial form is important for the development of the CL in primary FSGS. Normal podocytes resemble mesenchymal cells since they express both vimentin and WT1. In contrast, epithelial cells including parietal epithelial cells of the Bowman's capsule express both Pax2 and CK. Therefore, the mechanism of phenotypic change of podocytes in the CL in primary FSGS might be mesenchymal-epithelial transformation and a developmental paradigm.

Topics: Adult; Aged; Aged, 80 and over; DNA-Binding Proteins; Female; Glomerulosclerosis, Focal Segmental; Humans; Keratins; Kidney; Kidney Glomerulus; Male; Middle Aged; PAX2 Transcription Factor; Phenotype; Reference Values; Transcription Factors; WT1 Proteins

In primary focal segmental glomerulosclerosis (FSGS), phenotypic alteration of podocytes is important for the development of cellular lesions (CLs), which precede glomerular scar formation. WT1 and Pax2 are transcription factors involved in kidney development and phenotypic regulation of glomerular epithelial cells. However, the role of WT1 and Pax2 in the development of CLs in primary FSGS is unclear. Using immunohistochemistry, the expression of WT1, Pax2, and cytokeratin (CK), an epithelial marker never found in normal podocytes, was examined in 35 biopsy samples of primary FSGS. Segmental lesions were categorized as: (1) classic segmental scar (CS), (2) CL, and (3) monolayer epithelial (ME) lesion. In normal glomeruli, WT1 was strongly positive in podocytes and weakly positive in parietal epithelium of Bowman's capsule. Pax2 was strongly positive in parietal epithelium of Bowman's capsule, but never expressed in podocytes. Expression of WT1, Pax2, and CK was scantly positive in CSs. WT1 expression was decreased in CLs compared with unaffected podocytes, but Pax2 and CK were strongly expressed in CLs and podocytes of morphologically unaffected tufts in cases with CLs. WT1 expression was strong, as well as Pax2 and CK, in ME lesions. Clinically, urinary protein levels were significantly greater, and the interval from clinical onset to biopsy was significantly shorter in patients with CLs. These results suggest that re-expression of Pax2 in podocytes resulting in phenotypic change to a different epithelial form is one of the important changes for the development of CLs and ME lesions. Alteration from WT1 to Pax2 in podocytes may have an important role in the initiation of glomerular injury in primary FSGS.

Topics: Aged; DNA-Binding Proteins; Female; Glomerulosclerosis, Focal Segmental; Humans; Immunoenzyme Techniques; Keratins; Kidney; Male; Middle Aged; PAX2 Transcription Factor; Phenotype; Transcription Factors; WT1 Proteins