Fig 1: Brain-specific delivery of IL-2 drives microglial transcriptional divergence during TBI.a–h, Wild-type mice, treated with PHP.GFAP-IL-2 (or PHP.GFAP-GFP control vector) on day -14 were subjected to controlled cortical impacts to induce moderate TBI or sham surgery. At 14 d after TBI, T cells and microglia were sorted from the ipsilateral hemisphere of the perfused brains for 10x single-cell transcriptomics. a, T cells were clustered and annotated, based on markers defined in Extended Data Fig. 10a,b. Quantification of the Treg cell cluster based on group. b, Volcano plot showing differential gene expression in the Treg cell cluster between PHP.GFAP-GFP-treated mice and PHP.GFAP-IL-2-treated mice, for sham and TBI groups. c, Microglia uniform manifold approximation and projection (UMAP) representation, showing the location of cells per cluster for each treatment group. d, Cluster annotation based on expression of Apoe and H2-Eb1; expression of additional inflammatory markers is shown in Extended Data Fig. 10e. e, Quantification of the homeostatic and activated microglial clusters, and, within the activated microglial cluster, the relative contribution of the DAM and MHCIIhi subclusters. f, Volcano plot showing differential gene expression in the activated microglial cluster between PHP.GFAP-GFP-treated mice and PHP.GFAP-IL-2-treated mice, for TBI. g, Volcano plot showing differential gene expression, independent of treatment group, for the DAM versus MHCIIhi subclusters. h, Representative immunofluorescence staining of the cortical tissue at 14 d after TBI (n = 5, 6). NeuN, MHCII, DAPI and Iba1. Scale bar, 50 µm. Data from a and e are shown as the mean ± s.d.; n = 3 per group for TBI and n = 1 per group for sham. Statistical analyses were performed using unpaired two-tailed Student’s t-test (a and e) and volcano plots used the negative binomial test for differential expression (b, f and g).Source data