Fig. 4: Leukocyte infiltration at presymptomatic and early symptomatic stages in the innervation zone of the severely affected gastrocnemius (GC) muscle.

A, B Immunohistochemical analysis of CD45⁺ leukocytes in the innervation zone of the GC muscle in presymptomatic (A) and early symptomatic (B) hTDP-43^Tg/Tg mice (Tg/Tg) and age-matched wild-type (WT) littermates. NMJs were visualised with α-bungarotoxin (BTX), nuclei were labeled with DAPI (blue). Scale bar = 40 µm. C Violin plots showing quantitative analysis of CD45⁺ in the innervation zone of the GC muscle of presymptomatic (postnatal day 7; WT n = 4; Tg/Tg n = 3) and early symptomatic mice (postnatal day 15; WT n = 3; Tg/Tg n = 3), compared to late symptomatic mice (postnatal day 19 – data from Fig. 2). Each time point represents a separate cohort of mice. Bold dashed line represents median, thin dashed lines represent quartiles. D Violin plots showing quantitative analysis of CD68⁺ in the innervation zone of the GC muscle of presymptomatic (postnatal day 7; WT n = 4; Tg/Tg n = 3) and early symptomatic mice (postnatal day 15; WT n = 3; Tg/Tg n = 3), compared to late symptomatic mice (postnatal day 19 – data from Fig. 3). Each time point represents a separate cohort of mice. Bold dashed line represents median, thin dashed lines represent quartiles. Data analysis: (C) P7: unpaired, two-tailed t-test, p = 0.0003; (C) P15: unpaired, two-tailed t-test, p < 0.0001; (C) P19: two-tailed Mann-Whitney test [Shapiro-Wilk normality test, WT group: p = 0.0328, Tg/Tg group: p = 0.6879], p = 0.0286; (D) P7: unpaired, two-tailed t-test, (D) P15: unpaired, two-tailed t-test, (D) P19: unpaired, two-tailed t-test, p = 0.0034. n.s. = non-significant; * = p < 0.05; ** = p < 0.01; *** = p < 0.001.