Fig. 5: DC deficiency in the spleen of mice with Hmox1 deficiency or SCD.

A Left: Flow cytometry contour plots of spleen cell suspensions stained for CD11c and MHC class II from Hmox1^fl/fl Cre^neg and Hmox1^fl/fl Cre^pos mice at 6, 8, or 9 weeks after the induction of target gene recombination by tamoxifen treatment. The cells were gated from live CD45⁺ cells. Right: Flow cytometry density plots of the spleen cell suspensions from the mice analyzed at 9 weeks after tamoxifen induction. The suspensions were stained for CD45 and Ly6G. B Hematocrit, reticulocytes, and plasma concentration of heme-adducted albumin in SCD mice and wild-type littermates. C Left: Flow cytometry contour plots of spleen cell suspensions from SCD and wild-type mice stained for neutrophils (CD11b⁺ Ly6G⁺), macrophages (F4/80⁺), and DCs (CD11c⁺ MHC class II^high). The cells were run on a spectral flow cytometer and gated as live CD45⁺ CD3^_ CD19^_ cells. Right: Percentages of neutrophils, macrophages, and DCs in three SCD and control spleens. D Expression heatmap of heme and iron metabolism genes macrophages enriched populations isolated from the spleen of SCD and wild-type mice using anti-F4/80 antibody-coated magnetic dynabeads. The dot size indicates the fraction of cells expressing the genes, and the color indicates the normalized Z-score. E UMAP plot of pooled scRNA-seq data from two sequencing experiments with spleen cell suspensions from SCD and wild-type mice. Before sequencing, the spleen cells were enriched for DCs by negative selection using a DC isolation kit. The colors indicate the marker gene-derived cell-type attribution delineated in Supplementary Fig. 5. F UMAP plot of the scRNA-seq dataset split by genotype and colored by cell type. RNA velocity vectors are superimposed onto the UMAP plots with arrows indicating the velocity direction and magnitude (arrow length). G The stack bar charts illustrate each cell type as a proportion of the whole number of cells per sample. The data in B, C are presented as the means ± SDs. Each dot represents one mouse. t-test (B, C); n.s. not significant, *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001.