Urinary excretion of monocyte chemoattractant protein-1: a biomarker of active tubulointerstitial damage in patients with glomerulopathies.
OBJECTIVE
The urinary concentration of the monocyte chemoattractant protein-1 (uMCP-1) chemokine is increased in several proteinuric and/or inflammatory renal diseases. In the present study, we evaluated the association between uMCP-1 and renal function, proteinuria, glomerular and interstitial macrophage infiltration, and renal fibrosis in patients with primary and secondary glomerulopathies diagnosed by renal biopsy.


METHODS
Thirty-seven patients aged 32.6 +/- 7.7 years were studied. uMCP-1 was determined by ELISA. Renal macrophage expression (CD68 positive cells) is reported as number of macrophages/10(4) microm2 of the cortical tubulointerstitial (TI) area or of glomerular capillary tuft area. Cortical interstitial fibrosis was quantitated by PicroSirius red staining under polarized light by a computerized manner.


RESULTS
The uMCP-1 ratio (pg/ml/urinary creatinine mg/ml) was positively correlated (Spearman coefficient) with proteinuria (r = 0.4629; p < 0.005) and number of macrophages in the cortical TI area (r = 0.64; p = 0.0005), and negatively correlated with creatinine clearance (r = -0.4877; p < 0.001). The uMCP-1 ratio was not significantly correlated with number of macrophages/glomerular capillary tuft area (r = 0.27; p = 0.19) or with percent cortical interstitial fibrosis (r = 0.08; p = 0.62).


CONCLUSIONS
The uMCP-1 excretion is a biomarker of the inflammatory activity of the TI area, and does not reflect chronic interstitial damage.
Dantas
Márcio
M
Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil. mdantas@fmrp.usp.br
Romão
Elen Almeida
EA
Costa
Roberto Silva
RS
dos Reis
Marlene Antônia
MA
Vieira Neto
Osvaldo Merege
OM
Ribeiro
Richard Augusto
RA
Ravinal
Roberto Cuan
RC
Rodrigues Júnior
Antônio Luiz
AL
Coimbra
Terezila Machado
TM
D000328:Adult; D015415:Biomarkers / Q000652:urine; D018932:Chemokine CCL2 / Q000652:urine*; D005260:Female; D005921:Glomerulonephritis / Q000473:pathology / Q000652:urine*; D006801:Humans; D007678:Kidney Glomerulus / Q000473:pathology; D007684:Kidney Tubules / Q000473:pathology; D008297:Male; D009395:Nephritis, Interstitial / Q000473:pathology / Q000652:urine*