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Updated: Oct 19, 2026

Experimental Analysis of Apoptotic Thymocyte Engulfment by Macrophages
06:47

Experimental Analysis of Apoptotic Thymocyte Engulfment by Macrophages

Published on: May 24, 2019

Escherichia coli promotes macrophage apoptosis

K G Stravodimos1, P C Singhal, S Sharma

  • 1Department of Urology, Long Island Jewish Medical Center, New Hyde Park, New York, USA.

Journal of Endourology
|July 16, 1999
PubMed
Abstract

Insights

Escherichia coli strains can induce programmed cell death (apoptosis) in immune cells. This bacterial ability may contribute to virulence and kidney scarring in urinary tract infections (UTI).

Area of Science:

  • Microbiology
  • Immunology
  • Pathogenesis

Background:

  • Escherichia coli is a common cause of urinary tract infections (UTI).
  • Recurrent UTIs can lead to renal interstitial scarring.
  • Mononuclear cell infiltration is implicated in renal fibrosis and scarring.

Purpose of the Study:

  • To investigate the effects of pathogenic and non-pathogenic Escherichia coli strains on immune cell apoptosis.
  • To understand the role of bacterial virulence in inducing cell death relevant to UTI pathogenesis.

Main Methods:

  • Evaluation of two Escherichia coli strains: pathogenic BH-5 and non-pathogenic HB-101.
  • Assessment of the impact on human monocyte and murine macrophage apoptosis.
  • Analysis of apoptosis and necrosis induction in a time- and dose-dependent manner.

Main Results:

  • Pathogenic E. coli BH-5 significantly enhanced both apoptosis and necrosis in immune cells.
  • Non-pathogenic E. coli HB-101 also induced monocyte apoptosis, but to a lesser extent than BH-5.
  • Apoptosis and necrosis induction by E. coli BH-5 were time- and dose-dependent.

Conclusions:

  • Escherichia coli's capacity to induce apoptosis may be a key virulence factor.
  • Bacterial-induced apoptosis could play a significant role in the renal interstitial scarring associated with recurrent UTIs.

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