Fig. 6: TSPO is increased in microglia in SOD1G93A mice but not in ALS spinal cord.
a Representative images of TSPO expression in microglia and astrocytes in ALS spinal cord. b–d An increase was observed in microglia (P < 0.0001, t = 7.445, df = 19), HLA-DR+ microglia (P < 0.0001, t = 6.007, df = 19), and astrocytes (P < 0.0001, t = 9.024, df = 19) in ALS spinal cord when compared to controls. e A 2.5-fold increase of TSPO+ cells (P < 0.0001, t = 12.88, df = 19) was observed in the ALS spinal cord. f, g Up to a 3.4-fold increase in the density of TSPO+ microglia (TSPO + IBA1+ cell, P < 0.0001, t = 7.541, df = 19) (TSPO + HLA-DR+ cells, P < 0.0001, t = 3.368, df = 19) was observed. h TSPO+ astrocytes were significantly increased (P < 0.0001, t = 11.77, df = 19) in the spinal cord of ALS patients. i The increase in activated microglia and astrocytes was not associated with an increase in TSPO expression in microglia (P = 0.7684, t = 0.3046, df = 8) or in astrocytes (P = 0.5047, t = 0.6985, df = 8). j Representative images of TSPO expression in microglia and astrocytes in SOD1G93A spinal cord. k An increase was observed in microglia in SOD1G93A spinal cord when compared to controls at 16 weeks (P = 0.0115, t = 3.395, df = 7) but not at 10 weeks (P = 0.5334, t = 0.6509, df = 8). l An increase for astrocytes was observed for both 10 weeks (P = 0.0024, t = 4.362, df = 8) and 16 weeks (P = 0.0248, t = 2.848, df = 7). m An increase in TSPO+ cells was observed at 10 weeks (P = 0.0011, t = 4.931, df = 8) but not 16 weeks (P = 0.7299, t = 0.3594, df = 7). n No increase in the number of TSPO+ microglia was observed (10 weeks: P = 0.5244, t = 0.6656, df = 8; 16 weeks, P = 0.0930, t = 1.944, df = 7). o TSPO+ astrocytes were increased up to 15-fold in the spinal cord of SOD1G93A mice (10 weeks: P = 0.0003, t = 6.085, df = 8; 16 weeks: P = 0.382, t = 2.548, df = 7). p Despite no increase in the number of TSPO+ microglia, an increase in the amount of TSPO per cell was observed in microglia (P = 0.0451, t = 2.435, df = 7), but not astrocytes (P = 0.4052, t = 0.8856, df = 7) at 16 weeks. Biologically independent samples were used for all experiments (b–h n = 10 CON and n = 11 ALS) (i n = 5 CON and n = 5 ALS) (k–p 10 weeks: n = 5 WT and n = 5 SOD1G93A, 16 weeks: n = 4 WT and n = 5 SOD1G93A). Statistical significance in b–i, and k–p was determined by a two-tailed unpaired t-test. Box and whiskers mark the 25th to 75th percentiles and min to max values, respectively, with the median indicated. Scale bar = 50 µm, inserts are digitally zoomed in (200%). Source data are provided as a Source data file.
