ABSTRACT
COVID-19 is characterized by dysregulated thrombosis and coagulation that can increase mortality in patients. Platelets are fast responders to pathogen presence, alerting the surrounding immune cells and contributing to thrombosis and intravascular coagulation. The SARS-CoV-2 genome has been found in platelets from patients with COVID-19, and its coverage varies according to the method of detection, suggesting direct interaction of the virus with these cells. Antibodies against Spike and Nucleocapsid have confirmed this platelet-viral interaction. This review discusses the immune, prothrombotic, and procoagulant characteristics of platelets observed in patients with COVID-19. We outline the direct and indirect interaction of platelets with SARS-CoV-2, the contribution of the virus to programmed cell death pathway activation in platelets and the consequent extracellular vesicle release. We discuss platelet activation and immunothrombosis in patients with COVID-19, the effect of Spike on platelets, and possible activation of platelets by classical platelet activation triggers as well as contribution of platelets to complement activation. As COVID-19-mediated thrombosis and coagulation are still not well understood in vivo, we discuss available murine models and mouse adaptable strains.
Subject(s)
COVID-19 , Thrombosis , Mice , Animals , COVID-19/metabolism , SARS-CoV-2 , Blood Platelets/metabolism , Platelet ActivationABSTRACT
For the past 150 years, platelets have been recognized as the major blood component that mediates hemostasis and thrombosis. In more recent years, however, we have come to appreciate that platelets also perform profound immune functions during infection with various pathogens. We now recognize that platelets can also mediate a response to various RNA viruses such as influenza and that many viral infections, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can affect platelet count. Thrombocytopenia and increased coagulation have been independently associated with increased mortality. This article provides a perspective on the potential roles of platelets during coronavirus disease 2019.
ABSTRACT
[Figure: see text].