TABLE 1

Effects of platelet mediators on immune cells

	Platelet mediators	Effect on leukocytes	Species	Reference
Innate immunity
Neutrophil	P-selectin	Promotes the adhesion of neutrophils to endothelial cells and enhances neutrophil transendothelial migration	Mouse Human	[37]
	TLR4	Induces neutrophil activation and the release of NETs	Human	[38]
	CD40L	Enhances neutrophil ROS generation	Human	[39]
Monocyte	P-selectin and CCL5	Stimulate monocyte secretion of MCP-1 and IL-8	Human	[40]
	PF4	Enhances monocyte ROS generation	Human	[41]
	Prostaglandin E2	Promotes monocyte anti-inflammatory phenotype	Mouse Human	[42]
	CXCL12	Supports monocyte differentiation towards CD163⁺ macrophages	Human	[43]
Macrophage	GPIb, GPVI and thromboxane receptor	Promote macrophage polarisation toward pro-inflammatory phenotype and the release of pro-inflammatory mediators	Mouse Human	[44, 45]
Macrophage	Prostaglandin E2	Inhibits macrophage production of pro-inflammatory mediators	Mouse	[46]
Dendritic cell	CD40L	Induces DC differentiation and maturation	Human	[47, 48]
Dendritic cell	Nucleotides	Enhance the ability of DCs to induce T-cell proliferation	Human	[49]
NK cell	TGF-β	Inhibits NK cell degranulation and targets cell lysis	Mouse Human	[50–52]
Eosinophil	GM-CSF	Enhances eosinophil survival	Human	[53]
Eosinophil	P-selectin	Increases eosinophil attachment to endothelial cells	Mouse	[54]
Mast cell	PAF	Induces systemic mast cells activation and degranulation	Mouse Human	[55]
Adaptive immunity
CD4⁺ T-cell	PF4, CCL5 and TGF-β	Enhance the differentiation of stimulated CD4⁺ T-cells into Th1, Th17 and Treg	Human	[56]
CD8⁺ T-cell	MHC class I	Activates CD8⁺ T-cells	Mouse	[57]
CD8⁺ T-cell	CD40L	Enhance CD8⁺ T-cell cytotoxic response	Mouse	[58]
B-cell	CD40L	Induces isotype switching by B-cells	Mouse	[58, 59]

NK: natural killer; TLR: Toll-like receptor; NETs: neutrophil extracellular traps; ROS: reactive oxygen species; MCP: monocyte chemoattractant protein; IL: interleukin; PF: platelet factor; GP: glycoprotein; DC: dendritic cell; TGF: transforming growth factor; GM-CSF: granulocyte–macrophage colony-stimulating factor; PAF: platelet-activating factor; Th: T-helper cell; Treg: regulatory T-cell; MHC: major histocompatibility complex.