The Effect Of Polyhydroxyalkanoates Coated With PhaP-RGD On Human Bone Marrow Mesenchymal Stem Cells Adhesion And Proliferation

Polydroxyalkanoates(PHAs) is a family of microbially synthesized polyesters with over 150 different monomer unites reported so far. PHA polyesters with biodegradability, good biocompability and good mechanical properties is suitable for tissue engineering biomaterials. Human bone marrow-derived mesenchymal stem cells (hBMMSCs) can self-renew, have multiple differentiation potential and represent as an attractive cell source for regeneration of damaged tissues in tissue engineering. Amphiphilic PHA granule binding protein PhaP has been shown to be able to bind to hydrophobic surfaces of polymers, especially PHA, via strong hydrophobic interaction. The three tripeptide Arg-Gly-Asp(RGD) is a cell adhesion motif can be recgnized by many integrins , which is a family of cell-surface proteins, act as receptors for cell adhesion molecules. In this study, PhaP-RGD was successfully expressed and gained as a pure fusion protein in Escherichia coli BL21(DE3). PhaP-RGD protein can be successfully coated on surface of poly(3-hydroxybutyrate-co-3-hydroxy-hexanoate)(PHBHHx), poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(PHBV) and polylactic acid (PLA). Among the three kinds of films, PHBHHx film was demonstrated to have the strongest affinity to PhaP. In virto study showed that hBMMSCs attached better and grew faster on PhaP-RGD coated films (PHBHHx, PHBV and PLA) compared with their corresponding behaviors on Non-coated and PhaP coated films, respectively. There was no obvious difference result between PhaP coated and Non-coated films. These results demonstrated that PhaP-RGD could be used as a surface modification material to improve cell growth on hydrophobic biopolyester, which is a good method for some biomaterials to successfully apply to implant tissue engineering.