Functional Properties of a Purified Reconstituted Bilayer Matrix Design Support Natural Wound Healing Activities

Background: Advanced biomaterial engineering has produced unique wound care matrices using various tissue sources and processing methods. Source and process may impact the ability of the materials to assist in chronic wound healing. Recently we observed positive clinical outcomes when using an advanced Purified Reconstituted Bilayer Matrix (PRBM) to treat patients with chronic diabetic foot ulcers1.

This matrix consists of an upper compact layer and a lower porous layer, which mimic the structure of the basement membrane and dermis of human skin2.

Methods: This study evaluated the structural and functional characteristics of the PRBM biomaterial in vitro to determine how it may influence the chronic wound environment and key physiologic mechanisms necessary for healing. Investigations included scanning electron microscopy, cell culture analyses, gene expression assays, matrix metalloproteinase (MMP) activity assessment and measurement of pH. 

Results: Cross sectional scanning microscopy demonstrated a distinct bilayer scaffold with compact and porous layers. This PRBM structure allowed cell types involved in wound healing to bind and proliferate over time. Expression analyses of growth factor-responsive genes demonstrated binding and preservation of bioactive growth factors TGF-b1, bFGF, and VEGF by PRBM. Boyden chamber migration assay revealed increased migration compared to control.  In the presence of PRBM, MMP-1, MMP-2, and MMP-9 activity was significantly lower when compared to control samples. pH of the PRBM material extract solution was slightly acidic.

Conclusions: Based on in vitro evaluations, the PRBM possesses key characteristics to induce and support the natural wound healing process. These data support the promising clinical outcomes in diabetic foot ulcers.