Thromb Haemost 2006; 95(05): 815-821
DOI: 10.1160/TH05-07-0524
Platelets and Blood Cells
Schattauer GmbH

Platelets enhance CD4+ lymphocyte adhesion to extracellular matrix under flow conditions: Role of platelet aggregation, integrins, and non-integrin receptors

Alexey Solpov*
1   Department of Physiology, Chita Medical Academy, Chita, Russia
,
Boris Shenkman*
2   Institute of Thrombosis and Haemostasis, Sheba Medical Center, Tel-Hashomer, Israel
,
Yuri Vitkovsky
1   Department of Physiology, Chita Medical Academy, Chita, Russia
,
Grigory Brill
3   Saratov Medical University, Saratov, Russia
,
Alexander Koltakov
4   Laboratory of Immunoregulation, Department of Medicine, Sheba Medical Center and Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
,
Nahid Farzam
5   Goldschleger Eye Research Institute, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
,
David Varon
6   Coagulation Unit, Hadassah Hebrew University Medical Center, Jerusalem, Israel
,
Ilan Bank
4   Laboratory of Immunoregulation, Department of Medicine, Sheba Medical Center and Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
,
Naphtali Savion
5   Goldschleger Eye Research Institute, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
› Author Affiliations
Further Information

Publication History

Received 27 July 2005

Accepted after resubmission 14 March 2006

Publication Date:
01 December 2017 (online)

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Summary

The purpose of this study was to examine the role of platelets in CD4+ T lymphocyte adhesion to subendothelial extracellular matrix (ECM). Herpesvirus saimiri (HVS)-infected CD4+ T cells were incubated on ECM. An image analysis was used to evaluate T cell adhesion. Under static condition, T cell activation with 4-α-Phorbol 12-myristate 13-acetate (PMA) resulted in a 2.6-fold increase in cell adhesion. However, adhesion was not affected by platelets. In contrast, under flow (200s−1), platelets markedly enhanced both resting and PMA-activatedT cell adhesion (33- and 48-fold), forming lymphocyte-platelet co-aggregates that contain approximately 90% of the adherent T cells. Abrogation of platelet aggregation with tirofiban inhibited formation of platelet-T cell co-aggregates under flow and reduced T cell adhesion by 74%. Separate and combined blockade of CD40L and P-selectin glycoprotein-1 (PSGL-1) on PMA-activated lymphocytes reduced adhesion under flow in the presence of platelets by 28%, 33%, and 55%, respectively. Blockade of β1-integrins decreased adhesion under both static and flow conditions (by 35% and 44%, respectively), while blockade of β2-integrin reduced adhesion only under static condition (by 23%). A similar adhesion pattern was observed using CD4+ T cells isolated from normal donor peripheral blood. In conclusion, platelets support CD4+ lymphocyte adhesion to ECM under flow by formation of heterotypic platelet-lymphocyte co-aggregates involving αIIbβ3 integrin and β1-related integrins, as well as CD40L and PSGL-1.

* Contributed equally to the generation of the data presented in this manuscript.