A Revised Perspective of Skeletal Stem Cell Biology

Area of Science:

• Stem Cell Biology
• Regenerative Medicine
• Skeletal Biology

Background:

• Bone-related diseases pose a significant health challenge, stemming from imbalanced bone formation and resorption.
• Adult stem cells, particularly skeletal stem cells (SSCs), are a promising therapeutic target for skeletal dysfunction.
• Current understanding of pure SSC populations is limited by inconsistent definitions and isolation methods.

Purpose of the Study:

• To review the current state of skeletal stem cell (SSC) biology.
• To establish a consensus on the definition and terminology of bone-resident stem cells.
• To discuss recent advances in identifying and characterizing pure SSC populations.

Main Methods:

• Literature review of existing studies on skeletal stem cells (SSCs).
• Analysis of conflicting data regarding SSC isolation, detection, and functional evaluation.
• Examination of recent single-cell level investigations into SSC diversity.

Main Results:

• The precise identity and definition of a pure skeletal stem cell (SSC) population remain debated.
• Inconsistent methodologies and terminology (e.g., SSC vs. mesenchymal stromal/stem cell [MSC]) create confusion.
• Overlapping cell populations and unexplored heterogeneity complicate SSC research.

Conclusions:

• Clarifying SSC definition and terminology is essential for advancing skeletal regenerative medicine.
• Standardized criteria for SSC identification are needed to overcome current research hurdles.
• Further research into purified SSCs at the single-cell level will illuminate their diversity and regulation.