title: Soft substrates drive optimal differentiation of human healthy and dystrophic myotubes.
abstract: The in vitro development of human myotubes carrying genetic diseases, such as Duchenne Muscular Dystrophy, will open new perspectives in the identification of innovative therapeutic strategies. Through the proper design of the substrate, we guided the differentiation of human healthy and dystrophic myoblasts into myotubes exhibiting marked functional differentiation and highly defined sarcomeric organization. A thin film of photo cross-linkable elastic poly-acrylamide hydrogel with physiological-like and tunable mechanical properties (elastic moduli, E: 12, 15, 18 and 21 kPa) was used as substrate. The functionalization of its surface by micro-patterning in parallel lanes (75 microm wide, 100 microm spaced) of three adhesion proteins (laminin, fibronectin and matrigel) was meant to maximize human myoblasts fusion. Myotubes formed onto the hydrogel showed a remarkable sarcomere formation, with the highest percentage (60.0% +/- 3.8) of myotubes exhibiting sarcomeric organization, of myosin heavy chain II and alpha-actinin, after 7 days of culture onto an elastic (15 kPa) hydrogel and a matrigel patterning. In addition, healthy myotubes cultured in these conditions showed a significant membrane-localized dystrophin expression. In this study, the culture substrate has been adapted to human myoblasts differentiation, through an easy and rapid methodology, and has led to the development of in vitro human functional skeletal muscle myotubes useful for clinical purposes and in vitro physiological study, where to carry out a broad range of studies on human muscle physiopathology.
authors.affiliation: Dipartimento di Principi e Impianti di Ingegneria Chimica DIPIC, University of Padova, Padova, Italy. nicola.elvassore@unipd.it.
authors.forename: Elena
authors.initials: E
authors.lastname: Serena
authors.forename: Susi
authors.initials: S
authors.lastname: Zatti
authors.forename: Elena
authors.initials: E
authors.lastname: Reghelin
authors.forename: Alessandra
authors.initials: A
authors.lastname: Pasut
authors.forename: Elisa
authors.initials: E
authors.lastname: Cimetta
authors.forename: Nicola
authors.initials: N
authors.lastname: Elvassore
mesh_terms: D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation; D002478:Cells, Cultured; D006801:Humans; D018485:Muscle Fibers, Skeletal / Q000473:pathology*; D009136:Muscular Dystrophies / Q000473:pathology*; D012016:Reference Values; D023822:Tissue Engineering / Q000379:methods*