title: Albumin fiber scaffolds for engineering functional cardiac tissues.
abstract: In recent years attempts to engineer contracting cardiac patches were focused on recapitulation of the myocardium extracellular microenvironment. We report here on our work, where for the first time, a three-dimensional cardiac patch was fabricated from albumin fibers. We hypothesized that since albumin fibers' mechanical properties resemble those of cardiac tissue extracellular matrix (ECM) and their biochemical character enables their use as protein carriers, they can support the assembly of cardiac tissues capable of generating strong contraction forces. Here, we have fabricated aligned and randomly oriented electrospun albumin fibers and investigated their structure, mechanical properties, and chemical nature. Our measurements showed that the scaffolds have improved elasticity as compared to synthetic electrospun PCL fibers, and that they are capable of adsorbing serum proteins, such as laminin leading to strong cell-matrix interactions. Moreover, due to the functional groups on their backbone, the fibers can be chemically modified with essential biomolecules. When seeded with rat neonatal cardiac cells the engineered scaffolds induced the assembly of aligned cardiac tissues with high aspect ratio cardiomyocytes and massive actinin striation. Compared to synthetic fibrous scaffolds, cardiac cells cultured within aligned or randomly oriented scaffolds formed functional tissues, exhibiting significantly improved function already on Day 3, including higher beating rate (P = 0.0002 and P < 0.0001, respectively), and higher contraction amplitude (P = 0.009 and P = 0.003, respectively). Collectively, our results suggest that albumin electrospun scaffolds can play a key role in contributing to the ex vivo formation of a contracting cardiac muscle tissue.
authors.affiliation: The Laboratory for Tissue Engineering and Regenerative Medicine, Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Science, Tel Aviv University, Tel Aviv, 69978, Israel; Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv, 69978, Israel.
authors.forename: Sharon
authors.initials: S
authors.lastname: Fleischer
authors.forename: Assaf
authors.initials: A
authors.lastname: Shapira
authors.forename: Omri
authors.initials: O
authors.lastname: Regev
authors.forename: Nora
authors.initials: N
authors.lastname: Nseir
authors.forename: Eyal
authors.initials: E
authors.lastname: Zussman
authors.forename: Tal
authors.initials: T
authors.lastname: Dvir
mesh_terms: D000818:Animals; D055598:Chemical Phenomena; D046911:Macromolecular Substances / Q000737:chemistry / Q000378:metabolism*; D032342:Muscle Cells / Q000502:physiology*; D055503:Protein Multimerization; D051381:Rats; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism*; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds
chemical_list: D046911:Macromolecular Substances; D012710:Serum Albumin, Bovine
keywords: albumin scaffolds; cardiac tissue engineering; electrospinning