Fig. 3: TMEM175 conditional knockout suppresses B16-F10 lung metastasis through activating anti-tumor immunity.

B16-F10 cells (2 × 10⁵) were intravenously injected into WT and Tmem175^−/− sex-matched mice at 6–8 weeks old (n = 6 mice). Mice were euthanized on day 21. The lungs were weighed, and the metastatic nodules were counted. Then the lungs were minced and digested to prepare the single-cell suspension for FCM analysis. a TMEM175 conditional knockout inhibited B16-F10 lung metastasis. Scale bars indicate 1 cm. b, c Tmem175^−/− mice showed fewer lung metastatic nodules (b). Lung weights in Tmem175^−/− mice were decreased (c). d MHC-II^high AMs (gated from CD45⁺ CD11c⁺ CD11b⁻ CD64⁺ cells) were increased in Tmem175^−/− mice. e CD206^high AMs (gated from CD45⁺ CD11c⁺ CD11b⁻ CD64⁺ cells) were decreased in Tmem175^−/− mice. f MHC-II^high IMs (gated from CD45⁺ CD11b⁺ CD24⁻ CD64⁺ cells) were increased in Tmem175^−/− mice. g CD206^high IMs (gated from CD45⁺ CD11b⁺ CD24⁻ CD64⁺ cells) were decreased in Tmem175^−/− mice. h Subsets of IMs (IM1, IM2, and IM3) were altered by TMEM175 conditional knockout. i CD11c^low MHC-II^low IM1 (gated from CD45⁺ CD11b⁺ CD24⁻ CD64⁺ cells) were decreased in Tmem175^−/− mice. j CD11c^low MHC-II^high IM2 (gated from CD45⁺ CD11b⁺ CD24⁻ CD64⁺ cells) were decreased in Tmem175^−/− mice. k CD11c⁺ MHC-II^high IM3 (gated from CD45⁺ CD11b⁺ CD24⁻ CD64⁺ cells) were increased in Tmem175^−/− mice. CD4⁺ T cells (l), CD4⁺ CD69⁺ T cells (m), and CD4⁺ IFN-γ⁺ T cells (n) (gated from CD3⁺ cells) were increased in Tmem175^−/− mice. CD8⁺ T cells (o), CD8⁺ CD69⁺ T cells (p), CD8⁺ IFN-γ⁺ T cells (q), and CD8⁺ p15E-tetramer⁺ T cells (r) (gated from CD3⁺ cells) were increased in Tmem175^−/− mice. s Single cell sequencing was applied to evaluate the changes in the cell subsets and the transcriptome (n = 3 mice). Representative results from two independent experiments are presented as mean ± SEM, ns denotes not significant. Statistical significances in (b–g and i–r) were determined by two-sided unpaired t-test. Source data are provided as a Source data file.