Growth of embryonic stem cells in self-assembling scaffolds

Chavez, Ferman A
Department of Chemistry, Oakland University, Rochester, MI 48309

Abstract:

Self-assembling biocompatible and biodegradable nanomaterials have promising applications in tissue engineering and regenerative medicine as well as drug delivery.   Ideally suitable and active biological scaffolds will stimulate and promote cell differentiation.  Self-assembling scaffolds could help repair tissues which are difficult to regenerate and structures such as spinal cord, tendon and cartilage. We have investigated several synthetic nanomaterials (such as polycaprolactone, poly (ethylene oxide), poly(lactic acid), and poly(lactic acid co-glycolic acid) and biomolecules (such as proteins, peptides, and carbohydrates) for use in developing scaffolds that mimic in vivo microenvironments for 3-D tissue engineering.  The scaffolds promoted cellular growth of embryonic and cord blood stem cells and their differentiation into osteogenic, chondrogenic, and neural lineages.  We are currently developing nanomaterials that self-assemble to produce scaffolds for generating tissues of various organs such as heart and liver.   In this study we synthesized thiol-functionalized dextran (Dex-SH, Mn 25K) and investigated it for in situ hydrogel scaffold formation via Michael type addition using poly(ethylene glycol)tetra-acrylate (PEG-4-Acr).  Dex-SH was prepared by activation of the hydroxyl groups of dextran with 4-nitrophenyl chloroformate and the subsequent reaction with cysteamine. The Dex-SH is highly air sensitive in aqueous solution and must be handled under nitrogen.