title: Engineering vessel-like networks within multicellular fibrin-based constructs.
abstract: Sufficient vascularization in engineered tissues can be achieved through coordinated application of improved biomaterial systems with proper cell types. In this study, we employed 3D fibrin gels alone or in combination with the synthetic poly(l-lactic acid) (PLLA)/polylactic-glycolic acid (PLGA) sponges to support in-vitro construct vascularization and to enhance neovascularization upon implantation. Two multicellular assays were embedded in these constructs: (a) co-culture of endothelial (EC) and fibroblast cells, and (b) a tri-culture combination of ECs, fibroblasts and tissue specific skeletal myoblast cells. In-vitro vessel network formation was examined under advanced confocal microscopy in various time points from cell seeding. Vessel network maturity levels and morphology were found to be highly regulated by fibrinogen concentrations in-vitro. Combination of PLLA/PLGA sponges with fibrin matrices provided added mechanical strength and featured highly mature vessels-like networks. Implantation studies revealed that the implanted ECs developed into 3D interconnected vessel-like networks in-vivo. The PLLA/PLGA scaffold proved to be a key stimulator of neovascularization and perfusion of implanted grafts. Our findings demonstrate that complex biomaterial platform involving fibrin and PLLA/PLGA synthetic scaffold provide a way to enhancing vascularization in-vitro and in-vivo.
authors.affiliation: Department of Bio-Medical Engineering, Technion-Institute of Technology, Haifa 32000, Israel.
authors.forename: Ayelet
authors.initials: A
authors.lastname: Lesman
authors.forename: Jacob
authors.initials: J
authors.lastname: Koffler
authors.forename: Roee
authors.initials: R
authors.lastname: Atlas
authors.forename: Yaron J
authors.initials: YJ
authors.lastname: Blinder
authors.forename: Zvi
authors.initials: Z
authors.lastname: Kam
authors.forename: Shulamit
authors.initials: S
authors.lastname: Levenberg
mesh_terms: D000818:Animals; D001807:Blood Vessel Prosthesis; D002454:Cell Differentiation / Q000187:drug effects; D002477:Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005337:Fibrin / Q000494:pharmacology*; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D051379:Mice; D018613:Microscopy, Confocal; D032446:Myoblasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D018919:Neovascularization, Physiologic; D010477:Perfusion; D013917:Thrombin / Q000494:pharmacology; D013997:Time Factors; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D005337:Fibrin; D013917:Thrombin