SIGLEC1 and COVID-19: Of the five proteins differentially expressed in cMs, four [transferrin receptor (TFRC), sialic acid binding Ig-like lectin 1 (SIGLEC1), Fc fragment of IgG receptor 1a (FCGR1A), and leukocyte-associated Ig-like receptor 1 (LAIR1)] were higher expressed in COVID-19+ cases.