Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
J Biomed Mater Res A. 2022 Feb;110(2):245-256. doi: 10.1002/jbm.a.37280. Epub 2021 Jul 29.
The host immune response to an implanted biomaterial, particularly the phenotype of infiltrating macrophages, is a key determinant of biocompatibility and downstream remodeling outcome. The present study used a subcutaneous rat model to compare the tissue response, including macrophage phenotype, remodeling potential, and calcification propensity of a biologic scaffold composed of glutaraldehyde-fixed bovine pericardium (GF-BP), the standard of care for heart valve replacement, with those of an electrospun polycarbonate-based supramolecular polymer scaffold (ePC-UPy), urinary bladder extracellular matrix (UBM-ECM), and a polypropylene mesh (PP). The ePC-UPy and UBM-ECM materials induced infiltration of mononuclear cells throughout the thickness of the scaffold within 2 days and neovascularization at 14 days. GF-BP and PP elicited a balance of pro-inflammatory (M1-like) and anti-inflammatory (M2-like) macrophages, while UBM-ECM and ePC-UPy supported a dominant M2-like macrophage phenotype at all timepoints. Relative to GF-BP, ePC-UPy was markedly less susceptible to calcification for the 180 day duration of the study. UBM-ECM induced an archetypical constructive remodeling response dominated by M2-like macrophages and the PP caused a typical foreign body reaction dominated by M1-like macrophages. The results of this study highlight the divergent macrophage and host remodeling response to biomaterials with distinct physical and chemical properties and suggest that the rat subcutaneous implantation model can be used to predict in vivo biocompatibility and regenerative potential for clinical application of cardiovascular biomaterials.
宿主对植入生物材料的免疫反应,特别是浸润巨噬细胞的表型,是决定生物相容性和下游重塑结果的关键因素。本研究采用皮下大鼠模型,比较了由戊二醛固定牛心包(GF-BP)组成的生物支架的组织反应,包括巨噬细胞表型、重塑潜力和钙化倾向,GF-BP 是心脏瓣膜置换的标准治疗方法,与静电纺丝聚碳酸酯基超分子聚合物支架(ePC-UPy)、尿囊膜细胞外基质(UBM-ECM)和聚丙烯网(PP)的组织反应。ePC-UPy 和 UBM-ECM 材料在 2 天内诱导单核细胞渗透到支架的整个厚度,并在 14 天内诱导新生血管形成。GF-BP 和 PP 诱导产生了促炎(M1 样)和抗炎(M2 样)巨噬细胞的平衡,而 UBM-ECM 和 ePC-UPy 在所有时间点都支持占主导地位的 M2 样巨噬细胞表型。与 GF-BP 相比,ePC-UPy 在研究的 180 天内明显不易钙化。UBM-ECM 诱导了以 M2 样巨噬细胞为主的典型建设性重塑反应,而 PP 引起了以 M1 样巨噬细胞为主的典型异物反应。这项研究的结果强调了具有不同物理和化学性质的生物材料对巨噬细胞和宿主重塑反应的差异,并表明大鼠皮下植入模型可用于预测心血管生物材料的体内生物相容性和再生潜力。