IVD Development: Nucleus Pulposus Development and Sclerotome Specification
Purpose of Review
Intervertebral discs (IVD) are derived from embryonic notochord and sclerotome. The nucleus pulposus is derived from notochord while other connective tissues of the spine are derived from sclerotome. This manuscript will review the past 5 years of research into IVD development.
Over the past several years, advances in understanding the step-wise process that govern development of the nucleus pulposus and the annulus fibrosus have been made. Generation of tissues from induced or embryonic stem cells into nucleus pulposus and paraxial mesoderm derived tissues has been accomplished in vitro using pathways identified in normal development. A balance between BMP and TGF-ß signaling as well as transcription factors including Pax1/Pax9, Mkx, and Nkx3.2 appear to be very important for cell fate decisions generating tissues of the IVD.
Understanding how the IVD develops will provide the foundation for future repair, regeneration, and tissue engineering strategies for IVD disease.
KeywordsAxial skeleton development Sclerotome Notochord Annulus fibrosus Nucleus pulposus
Compliance with Ethical Standards
Conflict of Interest
Bashar Alkhatib, Ga I Ban, Sade Williams, and Rosa Serra declare no conflicts of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major Importance
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