title: A Dual-Mode Bioreactor System for Tissue Engineered Vascular Models.
abstract: In the past decades, vascular tissue engineering has made great strides towards bringing engineered vascular tissues to the clinics and, in parallel, obtaining in-lab tools for basic research. Herein, we propose the design of a novel dual-mode bioreactor, useful for the fabrication (construct mode) and in vitro stimulation (culture mode) of collagen-based tubular constructs. Collagen-based gels laden with smooth muscle cells (SMCs) were molded directly within the bioreactor culture chamber. Based on a systematic characterization of the bioreactor culture mode, constructs were subjected to 10% cyclic strain at 0.5 Hz for 5 days. The effects of cyclic stimulation on matrix re-arrangement and biomechanical/viscoelastic properties were examined and compared vs. statically cultured constructs. A thorough comparison of cell response in terms of cell localization and expression of contractile phenotypic markers was carried out as well. We found that cyclic stimulation promoted cell-driven collagen matrix bi-axial compaction, enhancing the mechanical strength of strained samples with respect to static controls. Moreover, cyclic strain positively affected SMC behavior: cells maintained their contractile phenotype and spread uniformly throughout the whole wall thickness. Conversely, static culture induced a noticeable polarization of cell distribution to the outer rim of the constructs and a sharp reduction in total cell density. Overall, coupling the use of a novel dual-mode bioreactor with engineered collagen-gel-based tubular constructs demonstrated to be an interesting technology to investigate the modulation of cell and tissue behavior under controlled mechanically conditioned in vitro maturation.
authors.affiliation: μBS Lab, Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133, Milan, Italy.|Laboratory for Biomaterials and Bioengineering (CRC-I), Department of Min-Met-Materials & CHU de Québec Research Center, Laval University, Pavillon Pouliot, Quebec City, QC, G1V 0A6, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Bono
authors.affiliation: Laboratory for Biomaterials and Bioengineering (CRC-I), Department of Min-Met-Materials & CHU de Québec Research Center, Laval University, Pavillon Pouliot, Quebec City, QC, G1V 0A6, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Meghezi
authors.affiliation: μBS Lab, Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133, Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Soncini
authors.affiliation: μBS Lab, Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133, Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Piola
authors.affiliation: Laboratory for Biomaterials and Bioengineering (CRC-I), Department of Min-Met-Materials & CHU de Québec Research Center, Laval University, Pavillon Pouliot, Quebec City, QC, G1V 0A6, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Mantovani
authors.affiliation: μBS Lab, Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133, Milan, Italy. gianfranco.fiore@polimi.it.
authors.forename: Gianfranco Beniamino
authors.initials: GB
authors.lastname: Fiore
mesh_terms: D019149:Bioreactors; D002478:Cells, Cultured; D003094:Collagen; D004548:Elasticity; D005782:Gels; D006801:Humans; D032389:Myocytes, Smooth Muscle / Q000502:physiology; D011651:Pulmonary Artery / Q000166:cytology; D023822:Tissue Engineering; D014783:Viscosity
chemical_list: D005782:Gels; D003094:Collagen
keywords: Bioreactor; Collagen; Cyclic strain; Mechanical properties; Smooth muscle cells; Vascular tissue engineering