Department of Biomedical Engineering, 415 Lane Road, Charlottesville, VA, 22903, USA.
Department of Chemical Engineering, 102 Engineer's Way, Charlottesville, VA, 22903, USA.
J Mater Chem B. 2021 Sep 15;9(35):7132-7139. doi: 10.1039/d1tb00715g.
Microporous annealed particle (MAP) hydrogel has been a promising scaffold platform technology to promote immediate tissue integration in injured tissue environments. The addition of growth factors has the potential to accelerate tissue integration and enhance scaffold-mediated healing. Growth factor releasing scaffolds face the translational hurdle of limited solubilized protein shelf stability; however, to address this hurdle we present a lyophilized MAP scaffold which can be effectively rehydrated directly prior to use. Our new approach includes a heterogenous MAP scaffold wherein 5% of the microgels contain immobilized heparin loaded with epidermal growth factor (EGF) at 1 μg mL. We demonstrate that these scaffolds, which are directly loaded with EGF following lyophilization maintain equivalent properties to scaffolds loaded passively diffusion into water-swollen microgels, including EGF release profiles and cell migration studies that did not significantly differ. Further, these heterogeneous scaffolds exhibit a significant increase in cellular migration and quicker re-epithelialization . This progress on spatially heterogenous growth factor release from MAP scaffolds has great potential to improve complex wound treatment and advance the field of growth factor releasing scaffolds.
微孔退火颗粒 (MAP) 水凝胶是一种很有前途的支架平台技术，可促进受伤组织环境中组织的即刻整合。添加生长因子有可能加速组织整合并增强支架介导的愈合。生长因子释放支架面临着可溶蛋白货架稳定性有限的转化障碍；然而，为了解决这个障碍，我们提出了一种冻干的 MAP 支架，它可以在使用前有效地重新水合。我们的新方法包括一种异质 MAP 支架，其中 5%的微凝胶含有固定化肝素，负载有 1μg/ml 的表皮生长因子 (EGF)。我们证明，这些支架在冻干后直接负载 EGF，保持与通过扩散被动加载到水膨胀微凝胶中的支架等效的特性，包括 EGF 释放曲线和细胞迁移研究，没有显著差异。此外，这些异质支架表现出细胞迁移的显著增加和更快的再上皮化。从 MAP 支架中空间异质释放生长因子的这一进展具有很大的潜力，可以改善复杂的伤口治疗并推动生长因子释放支架领域的发展。
