The monoclonal antibody SH-2, raised against human mesenchymal stem cells, recognizes an epitope on endoglin (CD105)

Biochem Biophys Res Commun. 1999 Nov;265(1):134-9. doi: 10.1006/bbrc.1999.1620.


Mesenchymal stem cells are multipotent cells resident in the bone marrow throughout adulthood which have the capacity to differentiate into cartilage, bone, fat, muscle, and tendon. A number of monoclonal antibodies raised against human MSCs have been shown to react with surface antigens on these cells in vitro. A protein of molecular mass 92 kDa was immunoprecipitated using the SH-2 monoclonal antibody. This was purified and identified by peptide sequencing analysis and mass spectrometry as endoglin (CD105), the TGF-beta receptor III present on endothelial cells, syncytiotrophoblasts, macrophages, and connective tissue stromal cells. Endoglin on MSCs potentially plays a role in TGF-beta signalling in the control of chondrogenic differentiation of MSCs and also in mediating interactions between MSCs and haematopoietic cells in the bone marrow microenvironment.

MeSH terms

  • Adult
  • Amino Acid Sequence
  • Antibodies, Monoclonal
  • Antigens, CD / analysis
  • Bone Marrow Cells / cytology*
  • Endoglin
  • Fetus
  • Humans
  • Macromolecular Substances
  • Mesoderm / cytology*
  • Molecular Sequence Data
  • Molecular Weight
  • Peptide Fragments / chemistry
  • Proteoglycans / analysis*
  • Proteoglycans / chemistry
  • Receptors, Cell Surface
  • Receptors, Transforming Growth Factor beta / analysis*
  • Receptors, Transforming Growth Factor beta / chemistry
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Stem Cells / cytology*
  • Trypsin
  • Vascular Cell Adhesion Molecule-1 / analysis*
  • Vascular Cell Adhesion Molecule-1 / chemistry


  • Antibodies, Monoclonal
  • Antigens, CD
  • ENG protein, human
  • Endoglin
  • Macromolecular Substances
  • Peptide Fragments
  • Proteoglycans
  • Receptors, Cell Surface
  • Receptors, Transforming Growth Factor beta
  • Vascular Cell Adhesion Molecule-1
  • betaglycan
  • Trypsin