CD105 protein depletion enhances human adipose-derived stromal cell osteogenesis through reduction of transforming growth factor β1 (TGF-β1) signaling

J Biol Chem. 2011 Nov 11;286(45):39497-509. doi: 10.1074/jbc.M111.256529. Epub 2011 Sep 23.


Clinically available sources of bone for repair and reconstruction are limited by the accessibility of autologous grafts, infectious risks of cadaveric materials, and durability of synthetic substitutes. Cell-based approaches for skeletal regeneration can potentially fill this need, and adipose tissue represents a promising source for development of such therapies. Here, we enriched for an osteogenic subpopulation of cells derived from human subcutaneous adipose tissue utilizing microfluidic-based single cell transcriptional analysis and fluorescence-activated cell sorting (FACS). Statistical analysis of single cell transcriptional profiles demonstrated that low expression of endoglin (CD105) correlated with a subgroup of adipose-derived cells with increased osteogenic gene expression. FACS-sorted CD105(low) cells demonstrated significantly enhanced in vitro osteogenic differentiation and in vivo bone regeneration when compared with either CD105(high) or unsorted cells. Evaluation of the endoglin pathway suggested that enhanced osteogenesis among CD105(low) adipose-derived cells is likely due to identification of a subpopulation with lower TGF-β1/Smad2 signaling. These findings thus highlight a potential avenue to promote osteogenesis in adipose-derived mesenchymal cells for skeletal regeneration.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipose Tissue / cytology
  • Adipose Tissue / metabolism*
  • Adolescent
  • Adult
  • Aged
  • Antigens, CD / metabolism*
  • Bone Regeneration / physiology
  • Cell Differentiation / physiology
  • Cells, Cultured
  • Endoglin
  • Female
  • Gene Expression Regulation / physiology*
  • Humans
  • Male
  • Microfluidic Analytical Techniques
  • Middle Aged
  • Osteogenesis / physiology*
  • Receptors, Cell Surface / metabolism*
  • Signal Transduction / physiology*
  • Smad2 Protein / metabolism
  • Stromal Cells / cytology
  • Stromal Cells / metabolism
  • Transcription, Genetic / physiology
  • Transforming Growth Factor beta1 / genetics
  • Transforming Growth Factor beta1 / metabolism*


  • Antigens, CD
  • ENG protein, human
  • Endoglin
  • Receptors, Cell Surface
  • SMAD2 protein, human
  • Smad2 Protein
  • Transforming Growth Factor beta1