Guerreiro Susana G, Oliveira Maria J, Barbosa Mário A, Soares Raquel, Granja Pedro L
INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal.
Cell Transplant. 2014;23(8):945-57. doi: 10.3727/096368913X670183. Epub 2013 Jul 17.
Promoting angiogenesis in a damaged tissue is a major challenge for tissue regeneration. Recent findings in tissue engineering suggest that fibroblasts (FBs) play an important role in orchestrating the angiogenic process. Fibroblasts maintain the structural integrity of connective tissue by continuously secreting growth factors and extracellular matrix precursors, which are essential for endothelial cell (EC) adhesion and spreading, thus playing a crucial role in angiogenesis. We hypothesized that FBs immobilized in alginate gels grafted with the RGD peptidic sequence could influence the recruitment of ECs to improve vascularization. In this work, the modulation of immobilized human FBs within the 3D synthetic extracellular matrix was assessed. Experiments using cocultures of ECs and FBs in indirect contact as well as angiogenic assays were performed to assess the influence of FBs immobilized in RGD-alginate in ECs' viability, stabilization, sprouting, and assembly into capillary-like structures. This study demonstrates the ability of FBs immobilized within RGD-alginate microspheres to modulate and support capillary-like structures' assembly. These findings indicate that the microenvironment created by these stromal cells in the scaffold modulates capillary morphogenesis, thus stimulating angiogenesis in situ and can potentially be used in regenerative medicine in clinical scenarios where vascularization is essential.
促进受损组织中的血管生成是组织再生面临的一项重大挑战。组织工程学的最新研究结果表明，成纤维细胞（FBs）在协调血管生成过程中发挥着重要作用。成纤维细胞通过持续分泌生长因子和细胞外基质前体来维持结缔组织的结构完整性，这些因子和前体对于内皮细胞（ECs）的黏附和铺展至关重要，因此在血管生成中起着关键作用。我们假设固定在接枝有RGD肽序列的藻酸盐凝胶中的成纤维细胞能够影响内皮细胞的募集，从而改善血管化。在这项工作中，评估了三维合成细胞外基质中固定化人成纤维细胞的调节作用。进行了内皮细胞与成纤维细胞间接接触共培养的实验以及血管生成测定，以评估固定在RGD - 藻酸盐中的成纤维细胞对内皮细胞活力、稳定性、芽生以及组装成毛细血管样结构的影响。本研究证明了固定在RGD - 藻酸盐微球中的成纤维细胞能够调节并支持毛细血管样结构的组装。这些发现表明，支架中这些基质细胞所创造的微环境能够调节毛细血管形态发生，从而在原位刺激血管生成，并有可能用于血管化至关重要的临床再生医学场景中。
