SOL-neuron material transfer in the adult mouse brain. (A) Sox10-iCreER ^T2 mice carrying Sun1-sfGFP or Rpl10a-EGFP reporter transgene with an upstream loxP-flanked DNA STOP sequence were used to induce nuclear or ribosomal reporter expression in Sox10-expressing cells by injection of TAM. (B) Experimental timeline and schematic of regional distribution of reporter-positive neurons at 4 d after TAM injection. (C and D) Reporter-positive NeuN⁺ neurons (arrowheads) in cortical layers 2–3 of Sox10-iCreER^T2:Sun1-sfGFP or Sox10-iCreER^T2:Rpl10a-EGFP mice at 4 d after TAM. Note the close positioning of SOL and reporter-positive neuronal nuclei (yellow box). The region of the yellow box is enlarged and shown as maximum intensity projection for individual channels and single plane image with orthogonal projection. (E) Cre expression was specific to Olig2⁺ SOL (arrows) in the cortex of Sox10-iCreER^T2:Sun1-sfGFP mice. No Cre expression was detected in reporter-positive neurons (arrowheads). (F) Quantification of reporter-positive Olig2⁺ SOL in the cortex of Sox10-iCreER^T2:Sun1-sfGFP mice at 4, 8, and 30 d after first TAM injection. (G and H) Quantification of reporter-positive NeuN⁺ neurons in the cortex of Sox10-iCreER^T2:Sun1-sfGFP or Sox10-iCreER^T2:Rpl10a-EGFP mice at 4, 8, and 30 d after first TAM injection. (I) Quantification of Sun1-sfGFP⁺ SOL-neuron nuclear pairs in the cortex of Sox10-iCreER^T2:Sun1-sfGFP mice at 4, 8, and 30 d after first TAM injection. (J) Positive correlation between the numbers of Sun1-sfGFP⁺ neurons and SOL-neuron nuclear pairs in the cortex after TAM injection determined by Pearson correlation analysis. (K) LPS (4 mg/kg) or saline were i.p. injected to 4–6-wk-old transgenic mice 3 d after TAM to induce systemic inflammation. (L) Sun1-sfGFP⁺ neurons (arrowheads), Iba1⁺ microglia, and GFAP⁺ astrocytes in the cortex of Sox10-iCreER^T2:Sun1-sfGFP mice at 24 h and 5 d after saline or LPS injection. (M) Quantification of Iba1⁺ microglia numbers in the cortex after saline or LPS injection. (N) Quantification of GFAP MFI in astrocytes in the cortex after saline or LPS injection. (O–Q) Quantification of reporter-positive NeuN⁺ neurons, SOL-neuron nuclear pairs and oligodendrocyte-lineage cells in the cortex at 24 h and 5 d after LPS injection. All data are presented as mean ± SEM. Each circle represents an individual animal. Data are representative of three independent experiments. P values were determined by one-way ANOVA with Bonferroni post hoc test. ns, P > 0.05; *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001. Scale bar: 50 µm for E and L; 25 µm for C and D and 10 µm for enlargements in C and D. A, amygdala; A.U., arbitrary units; CP, caudate putamen; Cx, cortex; Hip, hippocampus; Hy, hypothalamus; N, neuron; ns, not significant; Th, thalamus.