Expression of tenascin in normal and diseased human kidneys

Expression of tenascin was studied in normal human adult and fetal kidney specimens, and in renal tissues biopsied from patients with several types of glomerulonephritis. Immunofluorescent staining of the normal kidneys showed that tenascin was present weakly in the mesangial area and interstitium, but was absent from the glomerular capillaries. In the fetal kidney, tenascin was detected in the interstitium, but not in the immature glomeruli. In kidney tissues biopsied from patients with various renal diseases, expression of tenascin was associated with increased mesangial expansion and tubulointerstitial changes. In situ hybridization showed that tenascin mRNA was expressed in the renal tissues, but tenascin mRNA and tenascin protein were occasionally dissociated. These findings indicate that expression of tenascin is associated with mesangial expansion and also with tubulointerstitial changes in human glomerulonephritis. Tenascin expression may contribute to repair of injured glomeruli and interstitium.