Adhesion of Myoblasts to RGD-Alginate

Abstract

Several types of alginate have been developed, but none of them alone are able to interact with mammalian cells. Alginate does not provide anchorage points that are essential for cell growth and proliferation. As this hydrogel meets many requirements for tissue engineering, modification of alginate was proposed in order to stimulate cell adhesion. After recognition of RGD binding site in ECM proteins, synthetic RGD peptides were coupled with alginate via aqueous carbodiimide chemistry. I applied this conjugation and optimized it in terms of various parameters of the coupling reaction. Mouse skeletal Myoblasts were cultured on the surface of the modified alginate. They were attached, spread and differentiated to form myotubes. This showed that an RGD containing peptide has the ability to mimic ECM molecule binding sites and stimulate adhesion to materials that are otherwise unable to interact with cells. I also demonstrated that RGD density enhanced proliferation and spreading. Increasing crosslinker density made stiffer gels and controlled cell differentiation. Including free Ca2+ improved swelling properties of alginate gel, enforced cell attachment and enhanced conversion of myoblasts to myotubes.