Affiliations: Department of Pathology, Faculty of Medicine of
Ribeirão Preto, University of São Paulo, Brazil | Department of General Pathology, Faculty of Medicine
of Triângulo Mineiro, Uberaba, MG, Brazil | Division of Nephrology, Faculty of Medicine of
Ribeirão Preto, University of São Paulo, Brazil | Department of Physiology, Faculty of Medicine of
Ribeirão Preto, University of São Paulo, Brazil
Note: [] Corresponding author: R.S. Costa, Department of Pathology,
Faculty of Medicine of Ribeirão Preto, Av. Bandeirantes 3900, CEP
14049-900, SP, Brazil. Tel.:/Fax: +55 16 3633 1068; E-mail: rscosta@fmrp.usp.br
Abstract: IgA nephropathy (IgAN) is a kidney disease with a varying renal
prognosis. Recently, many studies have demonstrated that renal α-smooth muscle actin (α-SMA) and
transforming growth factor (TGF-β1) expression, as well
interstitial mast cell infiltrates could represent a prognostic marker in
several renal diseases. The aim of our study was to analyze the prognostic
value of mast cell, TGF-β1 and α-SMA expression in IgAN. A survey of the medical records and renal
biopsy reports of 62 patients with a diagnosis of IgAN followed-up from 1987 to
2003 was performed. The mean follow-up time was 74.7 ±
50.0 months. The immunohistochemical studies were performed using a monoclonal
antibody anti-human mast cell tryptase, a polyclonal antibody anti-human
TGF-β1, and a monoclonal antibody anti-human
α-SMA. An unfavorable clinical course of IgAN was
related to interstitial mast cell infiltrates and α-SMA expression in the tubulointerstitial area. Expression of
glomerular TGF-β1 and α-SMA,
and interstitial TGF-β1 is not correlated with clinical
course in IgAN. In conclusion, the increased number of mast cells and higher
α-SMA expression in the tubulointerstitial area may be
predictive factors for the poor prognosis of patients with IgAN.
Keywords: IgA nephropathy, TGF-β1, mast cells, α-SMA, renal fibrosis
