Modulating TRPV4 Channel Activity in Pro-Inflammatory Macrophages within the 3D Tissue Analog

Area of Science:

• Biomedical Engineering
• Cell Biology
• Immunology

Background:

• Macrophage plasticity is key for tissue regeneration.
• Transient Receptor Potential Vanilloid 4 (TRPV4) channels regulate cellular responses.
• Pharmacological modulation of TRPV4 in 3D macrophage models is understudied.

Purpose of the Study:

• To investigate the effects of TRPV4 modulators on macrophages in 3D matrices.
• To elucidate how TRPV4 modulation impacts macrophage phenotype, cytoskeletal structure, and gene expression.
• To explore TRPV4's potential in regulating inflammation for tissue regeneration.

Main Methods:

• U937-differentiated macrophages were cultured in 3D collagen matrices.
• Cells were treated with a TRPV4 agonist (GSK1016790A) and antagonist (RN-1734).
• Evaluated using structural (SEM, Masson's trichrome, CHP), morphological, and genotypic (qRT-PCR, IHC) techniques.

Main Results:

• TRPV4 modulation altered macrophage cytoskeletal structure and the surrounding 3D matrix.
• Agonist and antagonist treatments differentially modulated pro- and anti-inflammatory gene expression.
• TRPV4 antagonist significantly upregulated CD206 gene (9-fold) and surface marker (2.5-fold).

Conclusions:

• TRPV4 channel modulation effectively shifts macrophage phenotype within 3D matrices.
• This provides a novel strategy for controlling macrophage behavior in tissue regeneration.
• Potential applications in managing inflammation in musculoskeletal tissues.