Fig. 6: Macrophage Slamf1 restricts Mtb growth in vivo and in vitro.

A–D Slamf1^fl/fl LysM-Cre+ and Slamf1^fl/fl Cre- mice were infected with ~1000 CFU Mtb (mCherry-H37Rv), and lungs were harvested 4 wpi for flow cytometry, cytokine analysis, and CFU. (A) SLAMF1 positivity on infected myeloid cells. B Lung Mtb burden. C Number of Mtb-infected myeloid subsets. D Cytokine levels in the lung homogenates. A–D n = 17 mice in each group. Each data point represents one mouse. Data from 3 independent experiments. A **** p = 7.7  × 10⁻⁶ for pairwise comparison of CD11c+ non-AMs. C **** p = 1 × 10⁻¹⁵ comparing Cre- to Cre+ mice using Kruskal-Wallis. A–D P values from multiple Mann-Whitney t tests. E Fluorescence microscopy images showing bacteria (smyc’::mCherry-red), reporter (hspX::GFP-green), nuclei (DAPI-blue) and heatmap images of GFP intensity. BMDMs infected with reporter Mtb and co-cultured with or without T cells. Scale bars = 10 μm. F MFI of hspX::GFP signal for each bacterium measured from 10–15 images in each group from 2 independent experiments. Each data point is from one bacteria or a tightly clustered group of bacteria. **** p = 5 × 10⁻⁹. P values are from one-way ANOVA with Tukey multiple comparisons test. G Intracellular ROS production was compared between WT and Slamf1^−/− BMDMs. Macrophages were co-cultured with or without T cells upon P25 treatment. Each data point represents one biological replicate. n = 5-6 biological replicates from 3 independent experiments. P values from two-way ANOVA. H, I WT or Slamf1^−/− BMDMs were treated with IFN-γ, infected with H37Rv Mtb, and co-cultured with P25 TcR Tg T cells. CFU were calculated 4 hpi (day 0) and 3 dpi. I Samples were treated with or without NAC as indicated from five (H) or two (I) independent experiments, each with 6 replicates. P values from paired Student’s t test (H), One-way ANOVA (I). A–D, F–I, Data presented as mean values ± SEM. Source data are provided as a Source Data file.