Fig. 4. Microglial Lipo-AF co-localizes with engulfed synaptic material within microglia in the young adult mouse brain.

a Representative images of anti-VGluT2+ synaptic material excited (Ex) by a 561 nm laser, lipo-AF excited by a 635 nm laser and anti-IBA1+ microglia excited by a 488 nm laser in layer IV of the somatosensory cortex. Circles highlight engulfed anti-VGluT2+ synaptic material. Scale bar = 10 μm. b Quantification of the volume of VGluT2+ material colocalized with lipo-AF inside microglia., n = 3–4 mice (2 M, 2 F for each for P15, P30, P90; 2 M, 1 F for P5 and P60). One-way ANOVA with Dunnett’s multiple comparisons test (F = 192.1, df = 17, P5 vs P30 p = 0.0060, P5 vs P60 & P90 p < 0.0001). c Quantification of the volume of VGluT2+ material outside anti-IBA1+ microglia co-localized with lipo-AF. n = 3–4 mice (2 M, 2 F for each for P15, P30, P90; 2 M, 1 F for P5 and P60). One-way ANOVA with Dunnett’s multiple comparisons test (F = 13.01, df = 17, p = 0.0003). Representative image of anti-IBA1+ microglia with anti-VGluT2+ (d), anti-VGluT1+ (f), and anti-Homer1+ (h) synapses in the P90 somatosensory cortex. Scale bar = 10 μm. Quantification of the fluorescence intensity in arbitrary (arb.) units of total apparent VGluT2+ (e), VGluT1+ (g), or Homer1+ (i) puncta outside of anti-IBA1+ microglia (VGluT2 out, VGluT1 out, or Homer1 out) and inside of anti-IBA1+ microglia (VGluT2 in, VGluT1 in, Homer1 in) in the 561 nm channel and lipo-AF signal intensity in the 635 nm channel. e n = 3 mice (2 M, 1 F). One-way ANOVA with Tukey’s multiple comparisons test (F = 5.873, df = 8; VG2 out vs Lipo-AF p = 0.0353). g n = 3 mice (3 M). One-way ANOVA with Tukey’s multiple comparisons test (F = 9.090, df = 8; VG1 out vs Lipo-AF p = 0.0121). i n = 3 mice (3 M). One-way ANOVA with Tukey’s multiple comparisons test (F = 58.93, df = 8); *p < 0.05 **p < 0.01 ***p < 0.001 ****p < 0.0001. All data are represented as mean ± SEM. Source data are provided as a Source Data file.