Fol. Biol. 2012, 58, 57-63
Novel Flow Cytometric Method for the Detection of Podocalyxin-Positive Elements in Urine of Patients with Glomerulonephritides – First Promising Results
Glomerulonephritides together create a heterogenic group of supposedly immunologically mediated diseases of glomeruli. They still belong among the most frequent causes of chronic renal failure. Detection of podocytes in urine might serve as an important marker of glomerulonephritides activity. The aim of this study was to develop a novel flow cytometric method for the detection of podocyte fragments and podocytes in urine and assess its possible use in clinical practice. We placed emphasis on the improvement of pre-analytic phase. To suppress the autofluorescence of the background, blocking solutions and magnetic separation were used. An additional surface marker CD10 (nephrilysin) was used together with routinely used podocalyxin (PCX) in order to achieve better identification of podocytes. Based on the surface marker expression, three different element types were identified in the urine samples: PCX+/CD10+ elements (EL) (supposedly podocytes), PCX-/CD10+ EL (supposedly parietal epithelial cells) and PCX+ EL. We examined a total of 36 patients who underwent renal biopsy (non-glomerular nephropathy, MGN, FSGS, IgAN, AAV and MPGN) and 27 healthy controls. Negative results were found in non-glomerular nephropathy and in MGN. In patients with FSGS and IgAN, the levels of urine elements were slightly increased. The highest levels of all elements were found in AAV and MPGN. Our first results suggest that flow cytometric detection may distinguish between glomerular and nonglomerular diseases and that the levels of urine elements might correlate with the degree of glomerular destruction.
Keywords
podocyte, podocalyxin, CD10, glomerulonephritis, flow cytometry.
Funding
The study was supported by the Research Project MSM 0021620807 of the Ministry of Education, Youth and Sports of the Czech Republic, by project No. SVV-2011-262512 from Charles University in Prague and by the grant of the GAUK (Grant Agency of Charles University in Prague) No. 3209.
References
Copyright
This is an open-access article distributed under the terms of the Creative Commons Attribution License.
