DETERMINATION OF URINARY EXCRETION OF MONOCYTE CHEMOTACTIC PROTEIN-1 (MCP-1) AND TRANSFORMING GROWTH FACTOR-β1 (TGF-β1) IS AN INVASIVE METHOD OF ASSESSMENT OF TUBULOINTERSTITIAL FIBROSIS WITH CHRONIC GLOMERULONEPHRITIS

THE AIM of the investigation was to determine the concentration in urine and renal tissue of CGN patients of fibrinogenic mediators - monocyte chemotactic protein-1 (MCP-1) and transforming growth factor-β1 (TGF-β1) and to specify their significance for the assessment of processes of inflammation and fibrosis in the kidney and as the prognosis criteria. PATIENTS AND METHODS. Urinary excretion of MCP-1 and TGF-β1 using the immunoenzyme method (ELISA), and expression of TGF-β1 in kidney tissue using the immunohistochenical method were studied in 63 patients with active proteinuric forms of CGN. The interstitium area was measured by the morphometric method. RESULTS. Patients with active proteinuric forms of CGN unlike healthy subjects had higher urinary excretion of MCP-1 and TGF-β1. It was found that the level of urinary excretion of MCP-1 in patients with nephrotic syndrome was reliably higher than that in patients with a mild urinary syndrome. The urinary index MCP-1 was particularly high in patients with a stable renal failure. TGF-β1 excretion depended mainly on the creatininemia value, being the highest in patients with pronounced proteinuria and stable impairment of the kidney function. Intensive urinary excretion of TGF-β1 was observed in patients with CGN in whom expression of this cytokine in the kidney interstitium was revealed which confirmed its local-renal origin. The relationship of the urinary indices of MCP-1 and TGF-β1 was determined with the value of tubule-interstitial fibrosis. For the first time, high informative value (sensitivity and specificity) of urinary indices of MCP-1 and TGF-β1 as markers of the interstitial fibrosis degree was demonstrated and their significance in the prognosis of CGN. CONCLUSION. The investigation has demonstrated an important role of MCP-1 and TGF-β1 in the process of remodeling of tubulointerstitium. The indices under study are markers of TIF, and the determination of the level of MCP-1 and TGF-β1 in urine is an informative noninvasive method allowing activity of the disease and fibrosis stage to be monitored, and to estimate the prognosis of CGN.

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