title: Degradation characteristics, cell viability and host tissue responses of PDLLA-based scaffold with PRGD and β-TCP nanoparticles incorporation.
abstract: This study is aimed to evaluate the degradation characteristics, cell viability and host tissue responses of PDLLA/PRGD/β-TCP (PRT) composite nerve scaffold, which was fabricated by poly(d, l-lactic acid) (PDLLA), RGD peptide(Gly-Arg-Gly-Asp-Tyr, GRGDY, abbreviated as RGD) modified poly-{(lactic acid)-co-[(glycolic acid)-alt-(l-lysine)]}(PRGD) and β-tricalcium phosphate (β-TCP). The scaffolds' in vitro degradation behaviors were investigated in detail by analysing changes in weight loss, pH and morphology. Then, the 3-(4,5-dimethyl-2-thiazolyl) -2,5-diphenyl-2 -H-tetrazolium bromide (MTT) assay and cell live/dead assay were carried out to assess their cell viability. Moreover, in vivo degradation patterns and host inflammation responses were monitored by subcutaneous implantation of PRT scaffold in rats. Our data showed that, among the tested scaffolds, the PRT scaffold had the best buffering capacity (pH = 6.1-6.3) and fastest degradation rate (12.4%, 8 weeks) during in vitro study, which was contributed by the incorporation of β-TCP nanoparticles. After in vitro and in vivo degradation, the high porosity structure of PRT could be observed using scanning electron microscopy. Meanwhile, the PRT scaffold could significantly promote cell survival. In the PRT scaffold implantation region, less inflammatory cells (especially for neutrophil and lymphocyte) could be detected. These results indicated that the PRT composite scaffold had a good biodegradable property; it could improve cells survival and reduced the adverse host tissue inflammation responses.
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China;
authors.forename: Jiling
authors.initials: J
authors.lastname: Yi
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China;
authors.forename: Feng
authors.initials: F
authors.lastname: Xiong
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China;
authors.forename: Binbin
authors.initials: B
authors.lastname: Li
authors.affiliation: School of Medicine, University of Arizona, Tucson, AZ 85721, USA.
authors.forename: Heping
authors.initials: H
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China;
authors.forename: Yixia
authors.initials: Y
authors.lastname: Yin
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China;
authors.forename: Honglian
authors.initials: H
authors.lastname: Dai
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China;
authors.forename: Shipu
authors.initials: S
authors.lastname: Li
keywords: PDLLA/PRGD/β-TCP scaffold; cell viability; degradation; host tissue responses