In this review the authors compared the architecture of the 2 HSC niches …

• Abstract
• Introduction
• Homeostatic regulation of stem cells by the niche
• The role of the osteoblastic niche in supporting HSC maintenance
• The role of the vascular niche in supporting proliferation, differentiation, and transendothelial migration of HSCs
• The relationship between the osteoblastic and vascular niches
• Molecules that mediate signaling and adhesive interactions between stem cells and their niches
• Adhesion molecules in the stem cell niches
• The vascular niche
• Chemokines and other molecules involved in HSC/HPC homing and mobilization
• Not all osteoblasts function as part of the HSC niche
• Conclusion
• Acknowledgments
• References
• Figures

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