2 research outputs found
Development of a 3D tissue-engineered skeletal muscle and bone coāculture system
In vitro threeādimensional (3D) tissue engineered (TE) structures have been shown to better represent in vivo tissue morphology and biochemical pathways than monolayer culture, and are less ethically questionable than animal models. However, to create systems with even greater relevance, multiple integrated tissue systems should be recreated in vitro. In the present study, the effects and conditions most suitable for the coāculture of TE skeletal muscle and bone were investigated. Highāglucose Dulbecco's Modified Eagle Medium (HGāDMEM) supplemented with 20% foetal bovine serum (FBS) followed by HGāDMEM with 2% horse serum was found to enable proliferation of both C2C12 muscle precursor cells and TE85 human osteosarcoma cells, fusion of C2C12s into myotubes, as well as an upāregulation of RUNX2/CBFa1 in TE85s. Myotube formation was also evident within indirect contact monolayer cultures. Finally, in 3D coācultures, TE85 collagen/hydroxyapatite constructs had significantly greater expression of RUNX2/CBFa1 and osteocalcin/BGLAP in the presence of collagenābased C2C12 skeletal muscle constructs; however, fusion within these constructs appeared reduced. This work demonstrates the first report of the simultaneous coāculture and differentiation of 3D TE skeletal muscle and bone, and represents a significant step towards a full in vitro 3D musculoskeletal junction model
Hippo Pathway Effectors Control Cardiac Progenitor Cell Fate by Acting as Dynamic Sensors of Substrate Mechanics and Nanostructure
Stem cell responsiveness to extracellular matrix (ECM) composition and mechanical cues has been the subject of a number of investigations so far, yet the molecular mechanisms underlying stem cell mechano-biology still need full clarification. Here we demonstrate that the paralog proteins YAP and TAZ exert a crucial role in adult cardiac progenitor cell mechano-sensing and fate decision. Cardiac progenitors respond to dynamic modifications in substrate rigidity and nanopattern by promptly changing YAP/TAZ intracellular localization. We identify a novel activity of YAP and TAZ in the regulation of tubulogenesis in 3D environments and highlight a role for YAP/TAZ in cardiac progenitor proliferation and differentiation. Furthermore, we show that YAP/TAZ expression is triggered in the heart cells located at the infarct border zone. Our results suggest a fundamental role for the YAP/TAZ axis in the response of resident progenitor cells to the modifications in microĀenvironment nanostructure and mechanics, thereby contributing to the maintenance of myocardial homeostasis in the adult heart. These proteins are indicated as potential targets to control cardiac progenitor cell fate by materials design