S100A12 and COVID-19: Analysis of the SPP1 (CD44/integrins) and S100A12 (TLR4/CD36) receptor distribution in the lungs of COVID-19 patients demonstrated that many cell types expressed receptors for SPP1, including macrophages, neutrophils, T cells, and epithelial cells, whereas predominantly macrophages expressed receptors for S100A12 (Supplemental Figure 5).