COVID-19(26) Spike protein(13) Protein(13) IL6(13) Endothelial cell(11) host response(11) SARS-CoV-2(11) endocytosed(10) severe COVID-19(10) expression(10) spike protein.(10) viral spike protein(10) TNFα(9) SARS-CoV2(9) the spike protein(9) spike(9) fatal COVID-19(9) Viral protein(8) caspase 3(7) Viral RNA(7) endothelial(7) immunohistochemistry(7) hematoxylin(7) pseudovirion(7) caspase(7) pseudovirions(7) eosin(7) tissue(7) Hematoxylin and eosin(7) Brain(7)