Our scRNA-seq of COVID-19 lung tissues, together with previous RNA-seq and tissue staining data, has revealed the presence of SARS-CoV-2 transcripts in CD14+ monocytes and macrophages infiltrating the lungs, the spleen, lymph nodes, and the kidneys.37,41,42 How monocytes and macrophages became infected remains unclear. Here, CD14 is linked to COVID-19.