Single-cell transcriptomic analysis shows that the macrophage cluster cells that develop in presence of TCDD have a reduced M2 macrophage signature. (A) Expression of select TCDD-treatment induced differentially expressed genes in macrophages on days 21 and 28; ∗Bonferroni adjusted P value <.05. (B) Macrophage cluster was selected, and an M2 macrophage score was calculated based on expression of several genes (refer to “supplemental Methods”). M2 macrophage score within the macrophage cluster, and across time for vehicle and TCDD-treated groups is shown. Statistical significance of differences in M2 macrophage score between treatments at any time point was calculated using a Wilcoxon rank sum test. ∗P < .05. (C) TF activity (calculated with SCENIC) in the macrophage cluster for selected TFs across time is shown. Statistical significance of differences in TF activity between treatments at any time point was calculated using a Wilcoxon rank sum test. ∗P < .05. (D) GSEA using the Hallmark pathways database shows significantly enriched pathways in cells of the macrophage cluster owing to TCDD treatment at day 28. All enriched pathways have a Benjamini-Hochberg adjusted P value <.05. DOWN, downregulated pathways; NES, normalized enrichment score; UP, upregulated pathways.