Platelets Boost Recruitment of CD133+ Bone Marrow Stem Cells to Endothelium and the Rodent Liver-The Role of P-Selectin/PSGL-1 Interactions

Int J Mol Sci. 2020 Sep 3;21(17):6431. doi: 10.3390/ijms21176431.

Abstract

We previously demonstrated that clinical administration of mobilized CD133+ bone marrow stem cells (BMSC) accelerates hepatic regeneration. Here, we investigated the potential of platelets to modulate CD133+BMSC homing to hepatic endothelial cells and sequestration to warm ischemic livers. Modulatory effects of platelets on the adhesion of CD133+BMSC to human and mouse liver-sinusoidal- and micro- endothelial cells (EC) respectively were evaluated in in vitro co-culture systems. CD133+BMSC adhesion to all types of EC were increased in the presence of platelets under shear stress. This platelet effect was mostly diminished by antagonization of P-selectin and its ligand P-Selectin-Glyco-Ligand-1 (PSGL-1). Inhibition of PECAM-1 as well as SDF-1 receptor CXCR4 had no such effect. In a model of the isolated reperfused rat liver subsequent to warm ischemia, the co-infusion of platelets augmented CD133+BMSC homing to the injured liver with heightened transmigration towards the extra sinusoidal space when compared to perfusion conditions without platelets. Extravascular co-localization of CD133+BMSC with hepatocytes was confirmed by confocal microscopy. We demonstrated an enhancing effect of platelets on CD133+BMSC homing to and transmigrating along hepatic EC putatively depending on PSGL-1 and P-selectin. Our insights suggest a new mechanism of platelets to augment stem cell dependent hepatic repair.

Keywords: CD133; P-selectin; bone marrow stem cells; endothelial cells; liver regeneration; platelets.

MeSH terms

  • AC133 Antigen / metabolism*
  • Animals
  • Blood Platelets / physiology*
  • Endothelium, Vascular / cytology*
  • Endothelium, Vascular / metabolism
  • Liver / cytology*
  • Liver / metabolism
  • Male
  • Membrane Glycoproteins / metabolism*
  • Mesenchymal Stem Cells / cytology*
  • Mesenchymal Stem Cells / metabolism
  • Mice
  • Mice, Inbred C57BL
  • P-Selectin / metabolism*
  • Rats
  • Rats, Wistar

Substances

  • AC133 Antigen
  • Membrane Glycoproteins
  • P-Selectin
  • P-selectin ligand protein