A Macrophage-Based Cell Therapy Approach Promotes Collagen Deposition in Diabetic Wounds

Area of Science:

• Regenerative Medicine
• Immunology
• Biochemistry

Background:

• Macrophages are key to wound healing.
• Modulating macrophage activity offers a strategy for immune-mediated tissue regeneration.
• M2 monocytic cells and their secretomes are investigated for therapeutic potential.

Purpose of the Study:

• To investigate the therapeutic potential of M2 monocytic cell secretomes in wound healing.
• To assess the impact of endotoxin tolerization on M2 secretome properties and efficacy.
• To evaluate the effect of M2 secretomes on fibroblast activity and wound repair in vitro and in vivo.

Main Methods:

• Differentiated THP-1 cells were polarized to M2 phenotype with or without endotoxin tolerization.
• Secretomes were collected and analyzed for protein and cytokine content (LC-MS/MS, ELISA).
• In vitro (scratch assay) and in vivo (murine wound model) studies assessed fibroblast activity and wound healing outcomes.

Main Results:

• M2 secretomes, with or without tolerization, stimulated fibroblast migration and hydroxyproline release in vitro.
• In vivo, M2 secretomes significantly increased collagen deposition in wounds.
• No significant differences in healing outcomes were observed between tolerized and non-tolerized secretome treatments.
• Superficial wound closure and overall histology scores were not improved by secretome treatment.

Conclusions:

• M2 monocytic cell secretomes enhance extracellular matrix deposition, specifically collagen, in wound healing.
• Despite promoting collagen synthesis, M2 secretomes did not accelerate wound closure or improve overall healing.
• The data suggest M2 secretomes may increase the risk of excessive scar formation, warranting caution in therapeutic applications.