Berillo Dmitriy
Aarhus University, Denmark
Title: Cryogel based on polyelectrolyte complex for growth factor delivery
Biography
Biography: Berillo Dmitriy
Abstract
Bone regeneration is one of the most actively researched fields of regenerative medicine and bone fractures are the most common injuries of all large organs, especially in the aging population. Critical size defects require large-scale surgical interventions and auto-grafting is accepted as the gold standard treatment due to its osteogenic, osteoconductive and osteoinductive potentials. Issues such as a shortage of allografts, rejection issues and associated pain and morbidity from autografts require the development of alternative tissue engineering approaches that combine the principles of engineering and biology to create biomaterials, which are able to mimic or regenerate functionally active tissues. In this study a variety of natural polymer-based macroporous materials (biomaterials) were developed. Cryogels composed of chitosan (CHI), hydroxyapatite (HA), heparin (Hep) and polyvinyl alcohol (PVA) were prepared cross-linked by glutaraldehyde (GA) and treated with glycine. Addition of PVA into the reaction mixture slowed down the formation of a polyelectrolyte complex (PEC) between chitosan and heparin, allowing proper mixing, and producing to homogeneous preparation. Freezing of the CHI-HA-GA and PVA-Hep-GA mixture led to the formation of a non-stoichiometric PEC between opposite charged groups of CHI and Hep, which makes further efficient immobilization of bone morphogenic protein 2 (BMP-2) possible, due to electrostatic interactions. It was shown that the obtained cryogel matrix, loaded with BMP-2, stimulates the differentiation of rat BMSCs into the osteogenic lineage. Rat BMSCs attach to cryogel loaded with BMP-2 and express osteocalcin in vitro. Obtained composite cryogel with PEC may have a high potential for bone regeneration applications. In our future work, we plan to demonstrate the clinical efficacy of prepared cryogel for bone regeneration in an animal model. The following work is devoted to exploration of similar PEC and other biocompatible scaffolds for efficient attachment, migration and differentiation of BMSCs into chondrocytes for efficient regeneration of intervertebral disc.