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Updated: Aug 27, 2026

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

Engulfment of apoptotic cells is negatively regulated by Rho-mediated signaling

Annie-Carole Tosello-Trampont1, Kumiko Nakada-Tsukui, Kodi S Ravichandran

  • 1Beirne Carter Center for Immunology Research and the Department of Microbiology, University of Virginia, Charlottesville, Virginia 22908, USA.

The Journal of Biological Chemistry
|September 30, 2003
PubMed

Insights

Phagocytosis of apoptotic cells is crucial for health. This study reveals that inhibiting Rho-kinase signaling enhances the engulfment of cellular debris, offering new therapeutic avenues.

Area of Science:

  • Cell biology
  • Immunology
  • Molecular signaling

Background:

  • Phagocytosis of apoptotic cells is essential for tissue homeostasis and immune regulation.
  • The molecular mechanisms governing efficient cellular clearance are not fully understood.
  • Previous research implicated Rac and Cdc42, but Rho's role in phagocytosis remained unclear.

Purpose of the Study:

  • To investigate the role of Rho GTPases, specifically RhoA, in the process of apoptotic cell engulfment.
  • To determine the downstream effectors of RhoA involved in regulating phagocytosis.
  • To assess the therapeutic potential of modulating Rho signaling in phagocytic processes.

Main Methods:

  • Measurement of Rho-GTP levels during apoptotic cell engulfment.
  • Inhibition of Rho-mediated signaling using pharmacological inhibitors.
  • Overexpression of RhoA and its mutants in phagocytic cells.
  • Assessment of apoptotic cell uptake using quantitative assays.

Main Results:

  • Rho-GTP levels were found to decrease during the engulfment of apoptotic cells.
  • Inhibition of RhoA signaling significantly enhanced the uptake of apoptotic cells.
  • Activation or overexpression of RhoA inhibited phagocytosis.
  • Rho-kinase was identified as the primary downstream effector mediating RhoA's inhibitory effect.

Conclusions:

  • RhoA and its effector Rho-kinase negatively regulate the phagocytosis of apoptotic cells.
  • Inhibition of Rho/Rho-kinase signaling pathways enhances cellular clearance.
  • Targeting Rho-kinase may represent a viable therapeutic strategy for conditions involving impaired phagocytosis.

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