Efficacy of Crosslinking on Tailoring In Vivo Biodegradability of Fibro-Porous Decellularized Extracellular Matrix and Restoration of Native Tissue Structure: A Quantitative Study using Stereology Methods

Cholecyst‐derived extracellular matrix (CEM) is a fibro‐porous decellularized serosal layer of porcine gall‐bladder. CEM loses 90% of its weight at 48 h of in vitro collagenase digestion, but takes two months to be completely resorbed in vivo. Carbodiimide (EDC) crosslinking helps tailoring CEM's in vitro collagenase susceptibility. Here, the efficacy of EDC crosslinking on tailoring in vivo biodegradability of CEM is reported. CEM crosslinked with 0.0005 and 0.0033 × 103 M of EDC/mg that lose 80% and 0% of their weight respectively to in vitro collagenase digestion, were present even after 180 days in vivo. Quantitative histopathology using stereology methods confirmed our qualitative observation that even a tiny degree of crosslinking can significantly prolong the rate of in vivo degradation and removal of CEM. Non‐crosslinked CEM shows the phases of 1) granulation tissue deposition within its porous network, 2) resorption of scaffold, 3) concomitant replacement with host tissue (remodelling), and 4) restoration of native adipose tissue composition. The phases are significantly delayed even with minimal crosslinking using EDC.