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The cytoskeleton in phagocytosis and macropinocytosis

Sivakami Mylvaganam1, Spencer A Freeman1, Sergio Grinstein1

  • 1Program in Cell Biology, Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, 686 Bay Street, Toronto, ON M5G 0A4, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada.

Current Biology : CB
|May 25, 2021
PubMed

Insights

Innate immune cells use dynamic membrane protrusions like pseudopodia for phagocytosis and macropinocytosis. Cytoskeletal remodeling drives these processes and vacuolar compartment resolution.

Area of Science:

  • Cell Biology
  • Immunology
  • Biochemistry

Background:

  • Innate immune cells, including macrophages, neutrophils, and dendritic cells, are crucial for host defense and tissue homeostasis.
  • Their functions depend on sensing the environment through membrane protrusions, such as pseudopodia, lamellipodia, and filopodia.
  • These structures mediate the uptake of fluids (macropinocytosis) and particles (phagocytosis).

Purpose of the Study:

  • To elucidate the regulation and functions of cytoskeletal dynamics during macropinocytosis and phagocytosis.
  • To understand how cytoskeletal assembly and remodeling contribute to membrane deformation and vacuolar compartment formation and resolution.

Main Methods:

  • The study focuses on the cytoskeletal mechanisms underlying cellular processes.
  • It involves observing membrane dynamics and cytoskeletal rearrangements during phagocytosis and macropinocytosis.

Main Results:

  • Cytoskeletal polymers undergo coordinated rearrangements to generate forces for membrane protrusions.
  • These rearrangements are essential for plasma membrane deformation during macropinocytosis and phagocytosis.
  • The cytoskeleton also plays a key role in the remodeling and resolution of vacuolar compartments formed by these processes.

Conclusions:

  • Cytoskeletal assembly and remodeling are fundamental to the cellular processes of macropinocytosis and phagocytosis.
  • These dynamic cytoskeletal events enable innate immune cells to perform essential antimicrobial and homeostatic functions.

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