ACE2 and COVID-19: Overall, the above data confirm the hypothesis that altered anti-spike IgG glycosylation is sufficient to lead to platelet hyperreactivity and thrombosis in a manner similar to that caused by circulating MKs themselves [3], direct binding of SARS-CoV-2 spike protein to platelet ACE2 [39], SARS-CoV-2 RNA [37], or the virus itself [40] in severe cases of COVID-19.