Chapter 25 - Morphogenesis, Bone Morphogenetic Proteins, and Regeneration of Bone and Articular Cartilage

Abstract

Morphogenesis is the developmental cascade of pattern formation and body plan establishment, resulting in the final form of the organism. Morphogenesis is the basis of the fields of tissue engineering and regenerative medicine that is founded on the basis of morphogenetic signals, responding stem cells, and the extracellular matrix scaffolds. The goal of tissue engineering is the design and construction of spare parts for the human body to restore function to bone and articular cartilage and other tissues. Although bone has a high potential for regeneration, the adjacent articular cartilage is feeble in its capacity for repair and regeneration. Implantation of demineralized extracellular matrix from bone into subcutaneous sites induces local new bone induction. This experimental model permits the isolation and identification of bone morphogenetic proteins (BMPs), the morphogenetic signals for bone and cartilage morphogenesis. BMPs initiate and promote bone formation and a variety of tissues including articular cartilage, brain, eye, heart, and kidney, leading to the concept of BMPs as body morphogenetic proteins. This chapter will discuss the role of BMPs in bone and articular cartilage regenerative medicine and the remaining challenges. The rules of tissue morphogenesis gleaned from BMPs and bone may be applied universally to morphogenesis and regeneration of other organs and tissues, ushering us into the brave new world of the creation of spare parts for the human body based on signals, stem cells, and scaffolds of extracellular matrix.