CD34+ cells homing: Quantitative expression of adhesion molecules and adhesion of CD34+ cells to endothelial cells exposed to shear stress

Issue title: Selected papers of the Euromech Colloquium No. 420, Mechanobiology of Cells and Tissues

Article type: Research Article

Authors: Gigant, C.^; | Latger‐Cannard, V.^; | Bensoussan, D.^; | Fawzi, S. | Feugier, P.^; | Bordigoni, P. | Stoltz, J.F.^;

Affiliations: Mécanique et Ingénierie Cellulaire et Tissulaire, LEMTA, UMR CNRS 7563 Faculté de Médecine, 54505 Vandoeuvre‐lès‐Nancy, France | Service d'Hématologie Biologique, CHU Nancy, 54511 Vandoeuvre‐lès‐Nancy, France | Unité de Thérapie Cellulaire et Tissus, CHU Nancy, 54511 Vandoeuvre‐lès‐Nancy, France | Hématologie Adulte, CHU Nancy, 54511 Vandoeuvre‐lès‐Nancy, France | Hématologie Pédiatrique, CHU Nancy, 54511 Vandoeuvre‐lès‐Nancy, France

Note: [] Address for correspondence: Céline Gigant, Angiohématologie‐Hémorhéologie ‐ UMR CNRS 7563 ‐ LEMTA, Faculté de Médecine ‐ B.P. 184, 54505 Vandoeuvre‐lès‐Nancy Cedex, France. Tel.: +33 03 83 59 26 41; Fax: +33 03 83 59 26 84; E‐mail: [email protected]‐nancy.fr.

Abstract: To investigate the function of the main adhesion receptors (CD62L, CD49d, CD49e, CD11b and CD18) on CD34+ cells during homing, their expression was quantified by flow cytometry using calibration beads. CD34+ cells were isolated from bone‐marrow (BM), cord blood (CB) or peripheral blood (PB) from patients with myeloma. As this process might mimic the mature leukocyte migration, we also observed the effect of exposing endothelial cells to shear stress (7 dyn/cm2) on the adhesion of CB CD34+ cells. The proportion of CD34+/CD62L+ cells was greater in PB than in BM (p<0.05). Likewise, we found a significantly greater expression of CD62L receptor on PB cells compared to BM cells (p<0.05) and on BM cells compared to CB cells (p<0.05). The proportions of CD34+/CD49d+ cells and CD34+/CD49e+ cells were significantly higher in the BM and CB than in PB. However, no significant difference in CD49d or CD49e antigen densities was observed. The β2 integrins (CD11b and CD18) receptors are also implicated in CD34+ cells homing to BM. No significant variation in CD34+/CD11b+ and CD34+/CD18+ cells frequency was noted. However quantitative analysis revealed that CD18 was more strongly expressed on BM cells than on PB and CB cells. The adhesion assay showed that fluid flow may favour a firm adhesion of CB CD34+ cells to endothelial cells whereas static conditions just allowed CD34+ cells sedimentation. In conclusion, quantitative expression of the main receptors on CD34+ cells indicates that the three main sources of CD34+ cells currently used for transplantation have neither the same phenotype nor the same number of antigenic sites for a receptor. So, we hypothesize that migrational capacity of these cells might be different. Moreover, it seems that shear stress could favor adhesion of CD34+ cells to endothelial cells.

Keywords: Adhesion molecules, CD34+ cells, endothelial cells, hematopoietic stem cell transplantation, quantitative expression, shear flow

Journal: Biorheology, vol. 40, no. 1-3, pp. 189-195, 2003