Osteogenic potential: Comparison between bone marrow and adipose-derived mesenchymal stem cells.

Bone tissue engineering (BTE) is now a promising research issue to improve the drawbacks from traditional bone grafting procedure such as limited donor sources and possible complications. Stem cells are one of the major factors in BTE due to the capability of self renewal and multi-lineage differentiation. Unlike embryonic stem cells, which are more controversial in ethical problem, adult mesenchymal stem cells are considered to be a more appropriate cell source for BTE. Bone marrow mesenchymal stem cells (BMSCs) are the earliest-discovered and well-known stem cell source using in BTE. However, the low stem cell yield requiring long expansion time in vitro, pain and possible morbidities during bone marrow aspiration and poor proliferation and osteogenic ability at old age impede its' clinical application. Afterwards, a new stem cell source coming from adipose tissue, so-called adipose-derived stem cells (ASCs), is found to be more suitable in clinical application because of high stem cells yield from lipoaspirates, faster cell proliferation and less discomfort and morbidities during harvesting procedure. However, the osteogenic capacity of ASCs is now still debated because most papers described the inferior osteogenesis of ASCs than BMSCs. A better understanding of the osteogenic differences between ASCs and BMSCs is crucial for future selection of cells in clinical application for BTE. In this review, we describe the commonality and difference between BMSCs and ASCs by cell yield, cell surface markers and multiple-differentiation potential. Then we compare the osteogenic capacity in vitro and bone regeneration ability in vivo between BMSCs and ASCs based on the literatures which utilized both BMSCs and ASCs simultaneously in their articles. The outcome indicated both BMSCs and ASCs exhibited the osteogenic ability to a certain extent both in-vitro and in-vivo. However, most in-vitro study papers verified the inferior osteogenesis of ASCs; conversely, in-vivo research reviews revealed more controversies in this issue. We expect the new researchers can have a quick understanding of the progress in this filed and design a more comprehensive research based on this review.