[Frontiers in Bioscience S3, 61-68, January 1, 2011]

Tissue engineering of bone: an ectopic rat model

Itzhak Binderman1, Avinoam Yaffe2, Ron Zohar1, Dafna Benayahu3, Hila Bahar1

1Department of Oral Biology, Maurice and Gabriela Goldschleger School of Dental Medicine, 3Sackler Faculty of Medicine, Tel Aviv University, and 2Haddasah School of Dental Medicine, Hebrew University, Jerusalem

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Animal model for testing tissue engineering components
4. In vitro selection and expansion of progenitor cells and their transplantation to form bone, in vivo
5. Conclusions
6. Acknowledgment
7. References

1. ABSTRACT

Tissue engineering is attempting to recreate the complexity of living tissues. In order to test a variety of scaffolds or cells that are constantly being developed, we describe here a model where tissue engineering of bone in a non-osseous environment at subcutaneous thoracic site of DA rats generates. In this model, cell - matix interactions can mimic the normal cascade of bone development into a well organized ossicle like structure including newly formed bone marrow, during 3-4 weeks. Histogenesis of cartilage, bone and bone marrow is closely related to changes in molecular expression of essential early transcriptional regulators of osteoblast differentiation. We tested different organic, anorganic and polymeric scaffolds and their interaction with mesenchymal stem cells present in fresh bone marrow. In another series of experiments we tested mesenchymal populations separated from cultures of calvaria and periosteum for their ability to form bone in the same rat model. It is concluded that this in vivo model is very potent in studying cell-scaffold interactions affecting the temporal and spatial tissue engineering of bone.