Interactions Between Platelets and Liver Sinusoidal Endothelial Cells Initiate Liver Regeneration
1Division of Digestive and Transplantation Surgery, University Hospitals of Geneva, Geneva, Switzerland
2Geneva Medical School, Geneva, Switzerland
3Division of Angiology and Haemostasis, University Hospitals of Geneva, Geneva, Switzerland.
Meeting: 2015 American Transplant Congress
Abstract number: C1
Keywords: Effector mechanisms, Endothelial cells, Liver
Session Information
Session Name: Poster Session C: Antigen Presenting Cells in Alloimmune Responses/B Cells and Antibody in Alloimmune Responses
Session Type: Poster Session
Date: Monday, May 4, 2015
Session Time: 5:30pm-6:30pm
Presentation Time: 5:30pm-6:30pm
Location: Exhibit Hall E
Objectives
Platelets and liver sinusoidal endothelial cells (LSEC) were shown to be important contributors to liver regeneration. Several recent studies suggested that their interactions might be the key initiator of the regenerative process. The aim of this study was to investigate the interactions between platelets and LSEC that occur during liver regeneration.
Methods
To investigate the effects of contact between platelets and LSEC in vitro, mouse and human LSEC were isolated using collagenase digestion combined with density gradient centrifugation and magnetic sorting with anti-CD146 beads. CFSE-stained platelets, activated or not with thrombin, were co-cultured with LSEC for 1 hour and platelet internalization was assessed using confocal microscopy. IL-6 and EGF were measured by ELISA in the medium. To quantify the interactions between platelets and LSEC in vivo, mice were injected with PE anti-CD49b and AF488 CD146 antibodies and analyzed by intravital confocal microscopy. The proportions of adherent platelets within the liver vasculature were quantified after 30 minutes in mice subjected to 70% partial hepatectomy and in controls.
Results
Mouse and human platelets were internalized by species-specific LSEC, dependently on platelet activation (results are expressed as the number of internalized platelets per 100 LSEC: for mouse, resting platelets vs activated platelets: 32 vs 62, p<0.05, and for human: 45 vs 132, p<0.05). Increased levels of EGF were measured in the medium when human LSEC were co-cultured with activated platelets. Levels of IL-6 were similarly enhanced but the difference did not reach significance. After partial hepatectomy, platelets were significantly more adherent to LSEC than controls (results are expressed as the proportion of adherent platelets by the total number of platelets per FOV : 132/432 vs 41/214, p<0.05).
Conclusion
Platelet activation increases internalization by LSEC and promotes the secretion of EGF. After partial hepatectomy, platelets strongly adhere to LSEC.
To cite this abstract in AMA style:
Meyer J, Lejmi E, Fontana P, Morel P, Gonelle-Gispert C, Bühler L. Interactions Between Platelets and Liver Sinusoidal Endothelial Cells Initiate Liver Regeneration [abstract]. Am J Transplant. 2015; 15 (suppl 3). https://atcmeetingabstracts.com/abstract/interactions-between-platelets-and-liver-sinusoidal-endothelial-cells-initiate-liver-regeneration/. Accessed May 16, 2025.« Back to 2015 American Transplant Congress