Ultra-fine micronized human dermal matrix reprograms the chronic pressure-ulcer microenvironment to accelerate...

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Wound Healing Research

Background:

• Chronic pressure ulcers exhibit persistent inflammation, poor vascularization, and excessive extracellular matrix (ECM) degradation.
• Current treatments often struggle with uniform delivery to irregular wound beds, necessitating advanced injectable scaffolds.

Purpose of the Study:

• To evaluate the efficacy of ultra-fine micronized human acellular dermal matrix (UFM-hADM) as an injectable ECM scaffold for pressure ulcer treatment.
• To investigate the underlying mechanisms by which UFM-hADM promotes wound healing in a murine model.

Main Methods:

• Utilized a murine cyclic ischemia-reperfusion pressure-ulcer model to assess perilesional injection of UFM-hADM (∼70 μm) versus saline.
• Analyzed wound closure, re-epithelialization, dermal regeneration, collagen deposition, and molecular markers of inflammation, neovascularization, and ECM remodeling.
• Conducted reanalysis of public transcriptomic data from human pressure ulcers to compare molecular signatures.

Main Results:

• UFM-hADM significantly accelerated early wound closure and improved healing quality by Day 7 compared to saline.
• Demonstrated enhanced re-epithelialization, dermal regeneration, and collagen deposition.
• Mechanistically, UFM-hADM modulated the wound milieu by reducing pro-inflammatory cytokines (TNF-α, IL-6), increasing IL-10, promoting neovascularization (VEGF, CD31, α-SMA), and balancing ECM remodeling (COL1A1, COL3A1, MMP1, MMP3).

Conclusions:

• UFM-hADM acts as a pro-healing injectable ECM scaffold by coordinating immune, vascular, and matrix responses.
• Findings support the adjunctive clinical use of UFM-hADM for pressure ulcer healing.
• Exploratory clinical observations suggest acceptable tolerability and a favorable healing course.