Engineering a Bilayered Hydrogel to Control ASC differentiation

Abstract

Natural polymers over the years have gained more importance because of their host biocompatibility and ability to interact with cells in vitro and in vivo. An area of research that holds promise in regenerative medicine is the combinatorial use of novel biomaterials and stem cells. A fundamental strategy in the field of tissue engineering is the use of three-dimensional scaffold (e.g., decellularized extracellular matrix, hydrogels, micro/nano particles) for directing cell function. This technology has evolved from the discovery that cells need a substrate upon which they can adhere, proliferate, and express their differentiated cellular phenotype and function 2-3 . More recently, it has also been determined that cells not only use these substrates for adherence, but also interact and take cues from the matrix substrate (e.g., extracellular matrix, ECM) 4 . Therefore, the cells and scaffolds have a reciprocal connection that serves to control tissue development, organization, and ultimate function. Adipose-derived stem cells (ASCs) are mesenchymal, non-hematopoetic stem cells present in adipose tissue that can exhibit multi-lineage differentiation and serve as a readily available source of cells (i.e. pre-vascular endothelia and pericytes). Our hypothesis is that adipose-derived stem cells can be directed toward differing phenotypes simultaneously by simply co-culturing them in bilayered matrices 1 . Our laboratory is focused on dermal wound healing. To this end, we created a single composite matrix from the natural biomaterials, fibrin, collagen, and chitosan that can mimic the characteristics and functions of a dermal-specific wound healing ECM environment. Video LinkThe video component of this article can be found at http://www.jove.com/video/3953/ Protocol 1. Isolating Adipose-Derived Stem Cells (ASCs) 1, 5 Note: All procedures were performed at room temperature unless otherwise noted.

Enhancement of Skin Delivery of Drugs Using Proposome Depends on Drug Lipophilicity

“…The RHS preparation process is illustrated in Figure 3. Fibrinogen from bovine plasma, polyethylene glycol-4arm, and succinimidyl glutarate terminated were used to fabricate fibrin gels, following previously published reports [35,36]. Briefly, fabrication of PEG-fibrin gels was conducted by mixing PEG and fibrinogen in a ratio of 40:1, making the final concentration of fibrinogen and PEG to 10 mg/mL and 0.25 mg/mL, respectively.…”