CD4 and COVID-19: The hilar LNs from COVID-19 autopsies were selected to detect which cell subsets are positive for ACE2, and immunofluorescent double staining showed that ACE2 is expressed by SARS-CoV-2 NP positive cells, CD68+ macrophages and CD11c+ DCs, while it is absent on CD4+ and CD8+ T cells and B220+ B cells (Figure 3B).