Bone Regeneration Using Adipose-Derived Stem Cells in Injectable Thermo-Gelling Hydrogel Scaffold Containing Platelet-Rich Plasma and Biphasic Calcium Phosphate.

Han Liao,Ming-Jin Tsai,Manuri Brahmayya,Jyh-Ping Chen

doi:10.3390/ijms19092537

Abstract

For bone regeneration, a biocompatible thermo-gelling hydrogel, hyaluronic acid-g-chitosan-g-poly(N-isopropylacrylamide) (HA-CPN) was used as a three-dimensional organic gel matrix for entrapping rabbit adipose-derived stem cells (rASCs). Biphasic calcium phosphate (BCP) ceramic microparticles were embedded within the gel matrix as a mineralized bone matrix, which was further fortified with platelet-rich plasma (PRP) with osteo-inductive properties. In vitro culture of rASCs in HA-CPN and HA-CPN/PRP/BCP was compared for cell proliferation and osteogenic differentiation. Overall, HA-CPN/PRP/BCP was a better injectable cell carrier for osteogenesis of rASCs with increased cell proliferation rate and alkaline phosphatase activity, enhanced calcium deposition and mineralization of extracellular matrix, and up-regulated expression of genetic markers of osteogenesis. By implanting HA-CPN/PRP/BCP/rASCs constructs in rabbit critical size calvarial bone defects, new bone formation at the defect site was successfully demonstrated from computed tomography, and histological and immunohistochemical analysis. Taken together, by combining PRP and BCP as the osteo-inductive and osteo-conductive factor with HA-CPN, we successfully demonstrated the thermo-gelling composite hydrogel scaffold could promote the osteogenesis of rASCs for bone tissue engineering applications.

Highlights

Autogenous bone graft and bone substitutes are current approaches for bone defect repair after trauma, tumor ablation or infection [1]
We evaluate the biological response of rabbit adipose-derived stem cells in hyaluronic acid-gchitosan-g-poly(N-isopropylacrylamide) (HA-CPN) and Hyaluronic acid (HA)-CPN/platelet-rich plasma (PRP)/biphasic calcium phosphate (BCP) scaffolds in this study
The platelet concentration in our prepared PRP was determined to contain 3.2 ± 0.4 × 109 platelet/mL, which is ~10 times that in the blood collected for preparing PRP

Summary

Introduction

Autogenous bone graft and bone substitutes are current approaches for bone defect repair after trauma, tumor ablation or infection [1] These approaches all have drawbacks such as an unpredictable absorption rate, donor site morbidity, foreign body reaction, possible infection and unpredictable bone regeneration [2]. Bone tissue engineering (BTE) is a popular research topic for bone defect repair/regeneration, which consists of three main factors, i.e., cells, scaffolds and growth factors [3]. The revelation of such an idea is that stem cells could be osteo-induced into the osteoblast lineage by the action of growth factors that function as signaling molecules within the bone-mimetic three-dimensional (3D) scaffold for bone tissue formation [4]. The dispersion of calcium phosphate particles during implantation may be difficult in both ectopic and bony sites [13]

Methods

Results

Conclusion