TY - JOUR
T1 - Antagonistic Roles of Human Platelet Integrin aIIbβ3 and Chemokines in Regulating Neutrophil Activation and Fate on Arterial Thrombi Under Flow
AU - Schönichen, Claudia
AU - Montague, Samantha J
AU - Brouns, Sanne L N
AU - Burston, James J
AU - Cosemans, Judith M E M
AU - Jurk, Kerstin
AU - Kehrel, Beate E
AU - Koenen, Rory R
AU - Ní Áinle, Fionnuala
AU - O'Donnell, Valerie B
AU - Soehnlein, Oliver
AU - Watson, Steve P
AU - Kuijpers, Marijke J E
AU - Heemskerk, Johan W M
AU - Nagy, Magdolna
PY - 2023/9
Y1 - 2023/9
N2 - BACKGROUND: Platelets and neutrophils are the first blood cells accumulating at sites of arterial thrombus formation, and both cell types contribute to the pathology of thrombotic events. We aimed to identify key interaction mechanisms between these cells using microfluidic approaches. METHODS: Whole-blood perfusion was performed over a collagen surface at arterial shear rate. Platelet and leukocyte (in majority neutrophil) activation were microscopically visualized using fluorescent markers. The contributions of platelet-adhesive receptors (integrin, P-selectin, CD40L) and chemokines were studied by using inhibitors or antibodies and using blood from patients with Glanzmann thrombasthenia lacking platelet-expressed aIIbß3. RESULTS: We observed (1) an unknown role of activated platelet integrin aIIbß3 preventing leukocyte adhesion, which was overcome by short-term flow disturbance provoking massive adhesion; (2) that platelet-expressed CD40L controls the crawling pattern and thrombus fidelity of the cells on a thrombus; (3) that continued secretion of platelet substances promotes activation of identified neutrophils, as assessed by (fMLP induced) [Ca ] rises and antigen expression; (4) and that platelet-released chemokines activate the adhered cells in the order of CXCL7>CCL5>CXCL4. Furthermore, postsilencing of the platelets in a thrombus suppressed the leukocyte activation. However, the leukocytes on thrombi did no more than limitedly form neutrophil extracellular traps, unless stimulated with phorbol ester of lipopolysaccharide. CONCLUSIONS: Together, these findings reveal a multifaceted regulation of adhesion and activation of neutrophils by platelets in a thrombus, with a balanced role of several platelet-adhesive receptors and a promoting role of platelet-released substances. This multivalent nature of neutrophil-thrombus interactions offers novel prospects for pharmacological intervention.
AB - BACKGROUND: Platelets and neutrophils are the first blood cells accumulating at sites of arterial thrombus formation, and both cell types contribute to the pathology of thrombotic events. We aimed to identify key interaction mechanisms between these cells using microfluidic approaches. METHODS: Whole-blood perfusion was performed over a collagen surface at arterial shear rate. Platelet and leukocyte (in majority neutrophil) activation were microscopically visualized using fluorescent markers. The contributions of platelet-adhesive receptors (integrin, P-selectin, CD40L) and chemokines were studied by using inhibitors or antibodies and using blood from patients with Glanzmann thrombasthenia lacking platelet-expressed aIIbß3. RESULTS: We observed (1) an unknown role of activated platelet integrin aIIbß3 preventing leukocyte adhesion, which was overcome by short-term flow disturbance provoking massive adhesion; (2) that platelet-expressed CD40L controls the crawling pattern and thrombus fidelity of the cells on a thrombus; (3) that continued secretion of platelet substances promotes activation of identified neutrophils, as assessed by (fMLP induced) [Ca ] rises and antigen expression; (4) and that platelet-released chemokines activate the adhered cells in the order of CXCL7>CCL5>CXCL4. Furthermore, postsilencing of the platelets in a thrombus suppressed the leukocyte activation. However, the leukocytes on thrombi did no more than limitedly form neutrophil extracellular traps, unless stimulated with phorbol ester of lipopolysaccharide. CONCLUSIONS: Together, these findings reveal a multifaceted regulation of adhesion and activation of neutrophils by platelets in a thrombus, with a balanced role of several platelet-adhesive receptors and a promoting role of platelet-released substances. This multivalent nature of neutrophil-thrombus interactions offers novel prospects for pharmacological intervention.
KW - chemokines
KW - integrins
KW - neutrophils
KW - thrombasthenia
KW - thrombosis
U2 - 10.1161/ATVBAHA.122.318767
DO - 10.1161/ATVBAHA.122.318767
M3 - Article
SN - 1079-5642
VL - 43
SP - 1700
EP - 1712
JO - Arteriosclerosis Thrombosis and Vascular Biology
JF - Arteriosclerosis Thrombosis and Vascular Biology
IS - 9
ER -