1. Academic Validation
  2. Reprogramming of Myeloid Responses to Volumetric Muscle Loss via Engineered Protein Nanoparticles

Reprogramming of Myeloid Responses to Volumetric Muscle Loss via Engineered Protein Nanoparticles

  • ACS Nano. 2025 Aug 26;19(33):30441-30454. doi: 10.1021/acsnano.5c10604.
Jesus A Castor-Macias 1 2 Celeste Piotto 1 2 Paige Rudy 1 2 Steve D Guzman 1 2 Albert Chang 2 3 Jacqueline A Larouche 1 2 Yifei He 1 2 Benjamin Levi 4 Joerg Lahann 1 2 5 3 Carlos A Aguilar 1 2 6
Affiliations

Affiliations

  • 1 Dept. of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States.
  • 2 Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States.
  • 3 Dept. of Materials Science & Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States.
  • 4 Center for Organogenesis and Trauma, Department of Surgery, University of Texas Southwestern, Dallas, Texas 75235, United States.
  • 5 Dept. of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States.
  • 6 Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, Michigan 48109, United States.
Abstract

The acute loss of muscle tissue from trauma or surgery or volumetric muscle loss (VML) is a significant injury that results in chronic and sustained inflammatory responses that in turn impinge on recovery of neuromuscular function. Understanding and manipulating the immune response to volumetric muscle loss thus hold promise for limiting tissue damage and improving regenerative outcomes. Herein, we analyzed the monocyte and macrophage response to volumetric muscle loss injuries that result in fibrosis or regeneration and observed increased numbers of total immune cells, pro-inflammatory monocytes and macrophages, and scar-associated macrophages for VML injuries that result in fibrosis. Administration of the AMPK agonist AICAR reduced neutrophils and macrophages post-VML injury. Since AICAR possesses poor bioavailability, synthetic protein nanoparticles containing AICAR were created and showed strong uptake by immune cells after injury. Treatment of VML injuries with synthetic protein nanoparticles containing AICAR showed minimal trafficking to Other distal tissues and manipulation of macrophage phenotypes through phagocytosis and inflammatory signaling to Other cell types. These results establish a paradigm through which immune dysfunction can be targeted and controlled after volumetric muscle loss.

Keywords

Trem2; fibrosis; muscle stem cells; phagocytosis; single-cell RNA-Seq.

Figures
Products