Oxygen diffusivity of biologic and synthetic scaffold materials for tissue engineering

Abstract

Scaffolds for tissue engineering and regenerative medicine applications are commonly manufactured from synthetic materials, intact or isolated components of extracellular matrix (ECM), or a combination of such materials. After surgical implantation, the metabolic requirements of cells that populate the scaffold depend upon adequate gas and nutrient exchange with the surrounding microenvironment. The present study measured the oxygen transfer through three biologic scaffold materials composed of ECM including small intestinal submucosa (SIS), urinary bladder submucosa (UBS), and urinary bladder matrix (UBM), and one synthetic biomaterial, Dacron. The oxygen diffusivity was calculated from Fick's first law of diffusion. Each material permitted measurable oxygen diffusion. The diffusivity of SIS was found to be dependent on the direction of oxygen transfer; the oxygen transfer in the abluminal-to-luminal direction was significantly greater than the luminal-to-abluminal direction. The oxygen diffusivity of UBM and UBS were similar despite the presence of an intact basement membrane on the luminal surface of UBM. Dacron showed oxygen diffusivity values seven times greater than the ECM biomaterials. The current study showed that each material has unique oxygen diffusivity values, and these values may be dependent on the scaffold's ultrastructure.

Native extracellular matrix: a new scaffolding platform for repair of damaged muscle

“…Processing methods play a critical role in determining the type of host response (Valentin et al, 2009; Faulk et al, 2014a,b). The challenge faced by each decellularization method is to completely remove the cellular component and DNA content (less than 50ng of dsDNA per 1 mg dry weight of ECM scaffold) while preserving the ECM biochemical features, architecture, ultrastructure, and porosity (Crapo et al, 2011).…”

“…In particular, these factors are hypothesized to polarize the macrophage phenotype toward an M2 anti-inflammatory phenotype (Turner and Badylak, 2013), rather than toward an M1 pro-inflammatory phenotype, and to recruit different stem or progenitors cells that may give rise to new tissue formation (Agrawal et al, 2011a,b), vasculature and innervation (Agrawal et al, 2009; Sicari et al, 2012; Turner et al, 2012). Indeed, it has recently been demonstrated that native ECM scaffolds from skeletal muscle elicit M2 macrophage polarization during the host inflammatory response (Valentin et al, 2009; Turner and Badylak, 2013). M2 macrophages play a key role in the resolution of inflammation as well as in the activation of satellite cells during skeletal muscle regeneration (Kharraz et al, 2013).…”

Mass Transfer Analysis of Growth and Substance Metabolism of NSCs Cultured in Collagen-Based Scaffold In Vitro

“…It is well known that sufficient oxygen supplying can support cell survival and growth; this is especially true in the center of large scaffolds [56][57][58].…”

Engineering a stem cell house into a home

“…A first design concern is the nutrient and oxygen requirements of fully encapsulated stem cells [55,56]. Hydrogel systems with the flexibility to optimize matrix porosity can easily meet this design challenge and provide adequate energy requirements to maintain viability.…”