Furthermore, there were no significant differences in total N RNA levels at early times post infection (up to 6 hpi) between CD169+, ACE2+ or CD169+/ACE2+ THP1/PMA macrophages suggesting an absence of cell-intrinsic restrictions to early steps of SARS-CoV-2 replication, such as attachment and fusion, in CD169+ THP1/PMA macrophages. This evidence concerns the gene SIGLEC1 and infection.