Dissociation of tubular cell detachment and tubular cell death in clinical and experimental 'acute tubular necrosis'

L. C. Racusen, B. A. Fivush, Y. L. Li, I. Slatnik, K. Solez, A. Zapata, E. Monckton, D. Peteya, P. Atkins

Research output: Contribution to journalArticlepeer-review

Abstract

'Acute tubular necrosis' in humans is often characterized histologically by tubular cell loss and nonreplacement rather than by frank cellular necrosis. It has been assumed that tubular cells detach from the tubular basement membrane after the occurrence of irreversible cell injury and/or cell death. We examined voided urine from patients with native kidney and transplant kidney 'acute tubular necrosis' and found significant tubular cell shedding with up to 100% viability of voided tubular cells, as determined by exclusion of trypan blue. Histochemical stains for the brush border enzyme γ-glutamyl transpeptidase and electron microscopy of cell isolates demonstrated that 30 to 100% of the voided cells were of proximal tubule origin. Moreover, epithelial cell cultures were readily established from noncontaminated voided specimens, and more than 80% of the cells in monolayers expressed γ-glutamyl transpeptidase activity in vitro. Electron microscopy of cell monolayers confirmed proximal tubular differentiation in the majority of cells in the monolayer, with the remainder having an appearance more consistent with distal origin. In rabbit models of acute ischemic (pedicle clamp) and toxic (HgCl2 and glycerol-induced) injury, tubular cell shedding was also significant, with a mean of 25 to 30% of the voided cells viable. Epithelial cells were successfully cultured and passed from animals with ischemic renal injury. In vitro studies were carried out in cultured human proximal tubular cells to assess suitability of this system for more direct study of the phenomenon of cell detachment in response to injury. We found significant changes in cell shape in response to exposure to anoxia and HgCl2 in these cultures, with extensive cell rounding and retraction at times when cell viability remained high. This in vitro system could prove useful for defining mechanisms of renal tubular cell detachment in response to injury and for examining potential interventions to prevent epithelial disruption and loss of functional integrity. These strategies may ultimately have clinical relevance in patients with 'acute tubular necrosis.'

Original languageEnglish (US)
Pages (from-to)546-556
Number of pages11
JournalLaboratory Investigation
Volume64
Issue number4
StatePublished - Dec 1 1991

Keywords

  • Cell culture
  • Epithelial cells
  • Exfoliation
  • Ischemia
  • Nephrotoxins
  • Renal failure
  • Tubule

ASJC Scopus subject areas

  • Pathology and Forensic Medicine
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Dissociation of tubular cell detachment and tubular cell death in clinical and experimental 'acute tubular necrosis''. Together they form a unique fingerprint.

Cite this