Detection of Osteopontin mRNA in Epithelial Cells of Bowman’s Capsule as Revealed by in situ Hybridization
Recent Studies have revealed that tubulointerstitial damage with infiltration of macrophage occurs in the interstitium adjacent to tubules producing osteopontin mRNA and proteins. In this study, we examined the expression of the osteopontin gene in epithelial cells of Bowman's capsule in various glomerular injuring models, because these cells exist between the glomerular capillary tufts and interstitium. This result demonsrated that the osteopontin gene was expressed in the damaged tubular epithelial cells and epithelial cells of Bowman's capsule in three different models of glomerular diseases. These lesions were followed by a monocyte-macrophage influx. Given the evidence that osteopontin expression of the epithelial cells of Bowman's capsule appears with glomerular damage, and that it may be a monocyte-macrophage adhesive/chemotactic factor, our dara are consistent with the hypothesis that osteopontin may play an important role in monocyte-macrophage accumulation and glomerular damage, mainly extracapillary lesions.
