title: Engineering 3D Cellularized Collagen Gels for Vascular Tissue Regeneration.
abstract: Synthetic materials are known to initiate clinical complications such as inflammation, stenosis, and infections when implanted as vascular substitutes. Collagen has been extensively used for a wide range of biomedical applications and is considered a valid alternative to synthetic materials due to its inherent biocompatibility (i.e., low antigenicity, inflammation, and cytotoxic responses). However, the limited mechanical properties and the related low hand-ability of collagen gels have hampered their use as scaffold materials for vascular tissue engineering. Therefore, the rationale behind this work was first to engineer cellularized collagen gels into a tubular-shaped geometry and second to enhance smooth muscle cells driven reorganization of collagen matrix to obtain tissues stiff enough to be handled. The strategy described here is based on the direct assembling of collagen and smooth muscle cells (construct) in a 3D cylindrical geometry with the use of a molding technique. This process requires a maturation period, during which the constructs are cultured in a bioreactor under static conditions (without applied external dynamic mechanical constraints) for 1 or 2 weeks. The "static bioreactor" provides a monitored and controlled sterile environment (pH, temperature, gas exchange, nutrient supply and waste removal) to the constructs. During culture period, thickness measurements were performed to evaluate the cells-driven remodeling of the collagen matrix, and glucose consumption and lactate production rates were measured to monitor the cells metabolic activity. Finally, mechanical and viscoelastic properties were assessed for the resulting tubular constructs. To this end, specific protocols and a focused know-how (manipulation, gripping, working in hydrated environment, and so on) were developed to characterize the engineered tissues.
authors.affiliation: Laboratory for Biomaterials and Bioengineering, Department Min-Met-Materials Eng & CHU de Québec Research Center, Canada Research Chair I for the Innovation in Surgery, Laval University.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Meghezi
authors.affiliation: Laboratory for Biomaterials and Bioengineering, Department Min-Met-Materials Eng & CHU de Québec Research Center, Canada Research Chair I for the Innovation in Surgery, Laval University; NSERC CREATE Program for Regenerative Medicine (NCPRM), Laval University.
authors.forename: Dawit G
authors.initials: DG
authors.lastname: Seifu
authors.affiliation: Laboratory for Biomaterials and Bioengineering, Department Min-Met-Materials Eng & CHU de Québec Research Center, Canada Research Chair I for the Innovation in Surgery, Laval University; Department Electronics, Information and Bioengineering, Politecnico di Milano.
authors.forename: Nina
authors.initials: N
authors.lastname: Bono
authors.affiliation: NSERC CREATE Program for Regenerative Medicine (NCPRM), Laval University; Department of Chemical and Materials Engineering, University of Alberta; National Institute for Nanotechnology, National Research Council (Canada).
authors.forename: Larry
authors.initials: L
authors.lastname: Unsworth
authors.affiliation: Department of Chemical and Biochemical Engineering, University of Western Ontario.
authors.forename: Kibret
authors.initials: K
authors.lastname: Mequanint
authors.affiliation: Laboratory for Biomaterials and Bioengineering, Department Min-Met-Materials Eng & CHU de Québec Research Center, Canada Research Chair I for the Innovation in Surgery, Laval University; NSERC CREATE Program for Regenerative Medicine (NCPRM), Laval University; diego.mantovani@gmn.ulaval.ca.
authors.forename: Diego
authors.initials: D
authors.lastname: Mantovani
mesh_terms: D000818:Animals; D019149:Bioreactors; D001807:Blood Vessel Prosthesis; D001808:Blood Vessels / Q000502:physiology*; D018929:Cell Culture Techniques / Q000379:methods; D003094:Collagen; D005782:Gels; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D012038:Regeneration / Q000502:physiology*; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D005782:Gels; D003094:Collagen