Mesenchymal Stem Cells for Bone Repair and Metabolic Bone Diseases Anita H. Undale, MBBS, PhD, Jennifer J. Westendorf, PhD, Michael J. Yaszemski, MD, PhD, Sundeep Khosla, MD  Mayo Clinic Proceedings  Volume 84, Issue 10, Pages 893-902 (October 2009) DOI: 10.4065/84.10.893 Copyright © 2009 Mayo Foundation for Medical Education and Research Terms and Conditions

FIGURE Developmental hierarchy of stem cells (SCs) and therapeutic potential of human mesenchymal stem cells (MSCs). On fertilization of an egg, a blastocyst forms. The inner cell mass of the blastocyst consists of the most primitive SC or totipotent SC. This totipotent SC can give rise to cells of embryonic and extraembryonic origin. Pluripotent SCs are multipotent SCs that can self-renew and differentiate into hematopoietic SCs, endothelial SCs, and MSCs. Hematopoietic SCs differentiate into blood cells, whereas endothelial progenitors give rise to mature endothelial cells. However, MSCs are characterized by their multilineage differentiation potential, including for bone, cartilage, and adipose tissue. Human MSCs have been tested in several clinical applications to repair bone in different types of bone disease, including fracture nonunion, osteogenesis imperfecta, and hypophosphatasia. Mayo Clinic Proceedings 2009 84, 893-902DOI: (10.4065/84.10.893) Copyright © 2009 Mayo Foundation for Medical Education and Research Terms and Conditions