SIGLEC1 and COVID-19: CD169/SIGLEC1 expression levels on monocytes were evaluated in 51 hospitalized patients with mild COVID-19 (33/18 male/female, 57.1 ± 2.2 years of age), 51 hospitalized patients with severe COVID-19 (37/14 male/female, 62.5 ± 2.0 years of age) and 27 patients (14/13 male/female, 63.5 ± 3.93 years of age) with exclusion of COVID-19.