Transplantation of human-induced pluripotent stem cells carried by self-assembling peptide nanofiber hydrogel improves bone regeneration in rat calvarial bone defects.

Takeaki Shiga,Kamichika Hayashi,Shoko Onodera,Hiromi Ochiai-Shino,Akiko Saito,Toshifumi Azuma,Takahiko Shibahara

doi:10.1038/bdjopen.2015.7

Abstract

Objectives/Aims:The requisite conditions for successful bone tissue engineering are efficient stem cell differentiation into osteogenic cells and a suitable scaffold. In this study, we investigated in vivo bone regeneration from transplanted induced pluripotent stem cells (iPSCs).Materials and Methods:Two critical-sized calvarial bone defects were created in 36 rats. The surgical sites were randomly assigned to one of three treatments to test the healing effectiveness of the scaffold alone, scaffold with iPSCs or a salt solution as a control. The effectiveness of the treatments was evaluated after 2 or 4 weeks using radiographic and histological analyses of bone regeneration in the six groups.Results:Micro-computed tomography (CT) analysis of the bone defects found minimal bone regeneration with the salt solution and nanofiber scaffold and increased bone regeneration in defects repaired with iPSCs delivered in the nanofiber scaffold.Conclusion:Transplanted iPSCs encapsulated in a nanofiber scaffold can regenerate bone in critical-sized defects.

Highlights

Bone grafting is often performed to fill bone defects and promote bone regeneration.[1]
As a material that promotes the functioning of cells as an extracellular matrix, we considered the use of self-assembling peptide nanofiber hydrogel, a synthetic peptide consisting of a 16 amino-acid sequence.[24]
The micro-computed tomography (CT) images showed that bone formation occurred uniformly from the bony rims at the lateral edges of the bone defects in the nanofiber+induced pluripotent stem cells (iPSCs)-2w and nanofiber+iPSCs-4w groups

Summary

Introduction

Bone grafting is often performed to fill bone defects and promote bone regeneration.[1] Fresh autologous grafts remain the ‘gold standard’ for stimulating bone repair and regeneration,[2] but their availability may be limited and the procedure used to collect this material is associated with complications. This approach is not suitable for large defects and it has several risks, including donor site morbidity, graft or flap failure, rejection or infection.[3] In general, artificial bones made of various materials[4,5] are used because people still have difficulty in accepting the use of allografts.[6]. It is important to overcome limitations such as limited availability and the invasiveness of the procedures, which are often associated with many problems.[5,8,9]

Methods

Results

Conclusion