TREM2 and cancer: Figure 3e and f shows the marker genes in each subpopulation of macrophages. Enrichment scores of the two subpopulations in each cell are shown by t-SNE plots (Figure 3g and h). Moreover, the enrichment score of TREM2 + MAC and FOLR2 + MAC were significantly negatively correlated (r=−0.779) (Figure 3i). Communication between these two subpopulations and cancer epithelial cells is vigorous (Figure 3j). In addition, detection of TFs activity in each macrophage cell revealed that most of TFs had higher activity in FOLR2 + MAC cells (Figure 3—figure supplement 1).