Jawbone-like organoids generated from human pluripotent stem cells

Area of Science:

• Developmental Biology
• Stem Cell Biology
• Tissue Engineering

Background:

• Engineering jawbone tissue from pluripotent stem cells is difficult due to challenges in inducing specific progenitor cells and creating 3D osteocyte networks.
• The first pharyngeal arch ectomesenchyme (PA1) is the key progenitor for jawbone development.

Purpose of the Study:

• To develop a method for generating jawbone-like organoids from human induced pluripotent stem cells (hiPSCs).
• To investigate the recapitulation of mandibular development and osteogenesis imperfecta phenotypes.
• To assess the potential for bone regeneration using these engineered organoids.

Main Methods:

• A 3D culture system was used to differentiate hiPSCs into neural crest cells and then into mandibular prominence ectomesenchyme (mdEM).
• Exogenous pharyngeal epithelial signals were introduced to induce regional patterning in the mdEM.
• Osteogenic conditions were applied to promote the formation of jawbone-like organoids with osteoblasts and osteocytes.

Main Results:

• The mdEM exhibited proximal-distal patterning, mirroring natural mandibular development.
• Jawbone-like organoids formed, containing osteoblasts and network-forming osteocytes within mineralized bone matrices.
• Transplantation of organoids promoted bone regeneration in jaw defects and recapitulated osteogenesis imperfecta phenotypes using patient-derived hiPSCs.

Conclusions:

• The developed protocol successfully generates jawbone-like organoids from hiPSCs, mimicking key aspects of mandibular development.
• These organoids serve as a valuable model for studying human jaw embryology, bone pathophysiology, and genetic bone disorders like osteogenesis imperfecta.
• The findings provide a foundation for regenerative medicine approaches to jawbone repair.