This pathway describes platelet-mediated interactions with vascular or circulating cells. It is adapted from figure 2 in [https://www.ncbi.nlm.nih.gov/pubmed/29348254 Koupenova et al], in collaboration with Dr. Milka Koupenova.
Platelets interact with endothelial and immune cells in the circulation, and control the response to microbes, inflammatory stimuli, and vessel damage.
Through their TLRs or inflammatory signals, platelets can change their surface expression and release their granule content and in that way interact with different immune cells.
Platelets form heterotypic aggregates with other immune cells and initiate innate immune responses in the presence of TLR agonists and viruses (encephalomyocarditis virus, coxsackievirus B, dengue, flu and HIV).
Platelets can also interact with dendritic cells through P-selectin, and activate them to become antigen-presenting through their CD154.
Platelets engage the adaptive immune response by releasing their granule content which leads to IgG production and control of T-cell function.
Similarly, platelets are able to activate the endothelium, make it more permeable, and mediate leukocyte trafficking to the inflamed endothelium.
Description is adapted from Koupenova et al.bb3thrombosisDOID:0060903Human Disease OntologyplateletCL:0000233Cell Ontologyhemostasis pathwayPW:0000475Pathway Ontology29348254PubMedCirculating Platelets as Mediators of Immunity, Inflammation, and Thrombosis.Circ Res2018Koupenova MClancy LCorkrey HAFreedman JE