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Updated: May 16, 2026

Identification and Analysis of Myogenic Progenitors In Vivo During Acute Skeletal Muscle Injury by High-Dimensional Single-Cell Mass Cytometry
11:02

Identification and Analysis of Myogenic Progenitors In Vivo During Acute Skeletal Muscle Injury by High-Dimensional Single-Cell Mass Cytometry

Published on: December 1, 2023

Differentially activated macrophages orchestrate myogenic precursor cell fate during human skeletal muscle

Marielle Saclier1, Houda Yacoub-Youssef, Abigail L Mackey

  • 1INSERM, U1016, Institut Cochin, Paris, France.

Stem Cells (Dayton, Ohio)
|November 22, 2012
PubMed

Insights

Macrophages (MPs) sequentially orchestrate skeletal muscle regeneration by differentially regulating myogenic precursor cells (MPCs). Pro-inflammatory MPs initially inhibit MPC fusion, while anti-inflammatory MPs later promote MPC differentiation and myotube formation.

Area of Science:

  • Cell Biology
  • Immunology
  • Regenerative Medicine

Background:

  • Macrophages (MPs) play a dual role in tissue repair, influencing outcomes based on their activation state.
  • MPs are critical for adult skeletal muscle repair, interacting with myogenic precursor cells (MPCs).
  • The precise mechanisms of MP-MPC interactions in human skeletal muscle regeneration remain incompletely understood.

Purpose of the Study:

  • To investigate the in vitro and in vivo interactions between differentially activated human MPs and MPCs during skeletal muscle regeneration.
  • To elucidate the sequential roles of MPs in orchestrating adult myogenesis.

Main Methods:

  • In vitro co-culture systems to assess MP-MPC interactions.
  • In vivo analysis of regenerating human skeletal muscle tissue.
  • Assessment of cytokine/growth factor secretion by MPs.
  • Evaluation of MPC proliferation, differentiation, and myotube formation.
  • Immunohistochemical analysis of myogenic and MP markers in regenerating muscle.

Main Results:

  • In vitro, pro-inflammatory MPs inhibited MPC fusion, whereas anti-inflammatory MPs promoted MPC differentiation and myotube maturation.
  • In vivo, proliferating MPCs in regenerating muscle were associated with pro-inflammatory MPs.
  • Differentiating myogenin-positive MPCs were preferentially coupled with anti-inflammatory MPs.
  • Demonstrated a sequential orchestration of myogenesis by MPs during skeletal muscle regeneration in humans.

Conclusions:

  • Human macrophages sequentially regulate adult myogenesis during skeletal muscle regeneration.
  • MP activation state critically influences MPC fate, controlling skeletal muscle repair.
  • Inflammation, mediated by MP polarization, is a key regulator of stem cell behavior and tissue repair coordination.

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