Electrospun nano fibrous matrix with human bone marrow derived mesenchymal stem cells for bone tissue engineering

Abstract

Tissue engineering is an interdisciplinary approach which combines cell biology newlineand materials science with the purpose of developing implants using live cells and newlinesynthetic extracellular matrix. This thesis attempts this approach in order to newlinedevelop an alternative for autologous bone grafts. Electrospinning is one of the newlinewidely used techniques to fabricate polymeric fibers mimicking the structural newlinedimensions of extracellular matrix for bone tissue engineering applications. newlineHowever current bone tissue engineering approaches using electrospun nanofibers newlinedemand a construct design to address several major challenges in the field. newlineTherefore this thesis work is focussed on developing a construct design which can newlineaddress challenges such as cell infiltration and vascularisation in the construct, newlinecontrolling the degradability of the electrospun fibers, and the scalability of the newlineconstruct. In the first part of this PhD work we have extensively evaluated newlineelectrospun Poly (and#1028;-caprolactone) (PCL) nano-fibers, micro-fibers and human newlinemesenchymal stem cells (hMSCs) for bone tissue engineering purpose. Our results newlineindicated that hMSCs attached and spread rapidly on nano-fibrous scaffolds in newlinecomparison to micro-fibrous PCL. Further, hMSCs proliferated well on the nanofibrous newlinescaffolds. The cells on the nano-fibrous PCL were found to differentiate newlineinto the osteoblast lineage and subsequently mineralize upon addition of in vivo newlineosteogenic regulators. The attachment and spreading of hMSCs were more newlineeffective on the nano-fibers compared with the micro-fibers despite the lower newlineprotein surface coverage (total adsorbed protein per unit fiber surface area) on newlinenano-fibers. Thereafter, nano-fibrous semi-synthetic polymeric nanocomposite newlinescaffolds were engineered by incorporating a maximum of 15 wt. % biopolymeric newlinegelatin nanoparticles (nG) into the synthetic polymer PCL prior to electrospinning newlinein order to impart degradability to the nano-fibers.