title: Myoblast adhesion, proliferation and differentiation on human elastin-like polypeptide (HELP) hydrogels.
abstract: BACKGROUND
  The biochemical, mechanical and topographic properties of extracellular matrix are crucially involved in determining skeletal muscle cell morphogenesis, proliferation and differentiation. Human elastin-like polypeptides (HELPs) are recombinant biomimetic proteins designed to mimic some properties of the native matrix protein; when employed as myoblast adhesion substrates, they stimulate in vitro myogenesis. Given the influence that the biophysical properties of extracellular matrix have on skeletal muscle cells, the aim of this work was to investigate the effects of HELP hydrogels on myoblasts' viability and functions.
  
  
  METHODS
  We recently synthesized a novel polypeptide, HELPc, by fusing the elastin-like backbone to a 41aa sequence present in the α2 chain of type IV collagen, containing two arginyl-glycyl-aspartic acid (RGD) motifs. To obtain hydrogels, the enzymatic cross-linking of the HELPc was accomplished by transglutaminase. Here, we employed both non-cross-linked HELPc glass coatings and cross-linked HELPc hydrogels at different monomer densities, as adhesion substrates for C2C12 cells, used as a myoblast model.
  
  
  RESULTS
  By comparing cell adhesion, proliferation and differentiation, we revealed several striking differences. Depending on support rigidity, adhesion to HELPc substrates dictated cell morphology, spreading, focal adhesion formation and cytoskeletal organization. Hydrogels greatly stimulated cell proliferation, particularly in low-serum medium, and partially inhibited myogenic differentiation.
  
  
  CONCLUSIONS
  On the whole, the results underline the potential of these genetically engineered polypeptides as a tool for dissecting crucial steps in myogenesis.
authors: Department of Life Sciences, University of Trieste, Trieste - Italy.
authors: Paola
authors: P
authors: D'Andrea
authors: Department of Life Sciences, University of Trieste, Trieste - Italy.
authors: Deborah
authors: D
authors: Civita
authors: Department of Life Sciences, University of Trieste, Trieste - Italy.
authors: Michela
authors: M
authors: Cok
authors: Department of Life Sciences, University of Trieste, Trieste - Italy.|NanoInnovation Lab at ELETTRA Synchrotron Light Source, Basovizza, Trieste - Italy.
authors: Luisa
authors: L
authors: Ulloa Severino
authors: Department of Life Sciences, University of Trieste, Trieste - Italy.
authors: Francesca
authors: F
authors: Vita
authors: Department of Life Sciences, University of Trieste, Trieste - Italy.|NanoInnovation Lab at ELETTRA Synchrotron Light Source, Basovizza, Trieste - Italy.
authors: Denis
authors: D
authors: Scaini
authors: NanoInnovation Lab at ELETTRA Synchrotron Light Source, Basovizza, Trieste - Italy.
authors: Loredana
authors: L
authors: Casalis
authors: Department of Life Sciences, University of Trieste, Trieste - Italy.|B.R.A.I.N. Centre for Neuroscience, University of Trieste, Trieste - Italy.
authors: Paola
authors: P
authors: Lorenzon
authors: Department of Life Sciences, University of Trieste, Trieste - Italy.
authors: Ivan
authors: I
authors: Donati
authors: Department of Life Sciences, University of Trieste, Trieste - Italy.
authors: Antonella
authors: A
authors: Bandiera
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002454:Cell Differentiation; D049109:Cell Proliferation; D024141:Collagen Type IV / Q000737:chemistry; D004549:Elastin / Q000737:chemistry*; D005109:Extracellular Matrix / Q000737:chemistry*; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D051379:Mice; D032446:Myoblasts / Q000166:cytology / Q000378:metabolism*; D009842:Oligopeptides / Q000737:chemistry
chemical_list: D024141:Collagen Type IV; D020100:Hydrogels; D009842:Oligopeptides; C047981:arginyl-glycyl-aspartic acid; D004549:Elastin