Fig. 3

Lack of α-synuclein pathology in LB-SG-injected mice. a Immunohistochemistry of human α-synuclein (hSyn, in brown; thionin staining in purple) in the SNpc of LB-SG-injected mice at 24 h post-inoculation. b Left, representative photomicrographs of endogenous murine α-synuclein immunostaining (in brown) in the SN of Ctrl- and LB-SG-injected animals at 6 months post-inoculation. Right, number of α-synuclein-immunopositive neurons in the ipsilateral SNpc of Ctrl- and LB-SG-injected mice, relative to vehicle-injected animals, at 6 months post-inoculations. Ctrl: n = 5; mean = 119.8; SD = 29.38; SEM = 13.14; LB-SG: n = 9; mean = 89.14; SD = 27.94; SEM = 9.313; p = 0.0768, two-tailed t-test. c Quantification of intracellular levels of endogenous murine α-synuclein within ipsilateral SNpc neurons by optical densitometry (OD) in Ctrl- and LB-SG-injected mice, relative to vehicle-injected animals, at 6 months post-inoculations. Ctrl: n = 645; mean = 109.3; SD = 37.06; SEM = 1.459; LB-SG: n = 603; mean = 110.8; SD = 34.27; SEM = 1.396; p = 0.32, Mann-Whitney rank sum test. d Quantification of regional levels of endogenous murine α-synuclein by OD in the ipsilateral SN of Ctrl- and LB-SG-injected mice at 6 months post-inoculations, relative to vehicle-injected animals, after proteinase K (PK) digestion (1 μg/ml for 10 min). Ctrl: n = 6; mean = 106.5; SD = 15.82; SEM = 6.458; LB-SG: n = 12; mean = 114.6; SD = 14.61; SEM = 4.218; p = 0.2959, two-tailed t-test. e Number of phosphorylated α-synuclein (pSyn)-immunopositive neurons in the ipsilateral SNpc of Ctrl- and LB-SG-injected mice, relative to vehicle-injected animals, at 6 months post-inoculations. Ctrl: n = 8; mean = 173.9; SD = 85.39; SEM = 30.19; LS-SG: n = 10; mean = 145.7; SD = 30.83; SEM = 9.749, p = 0.3435, two-tailed t-test. f Quantification of regional levels of pSyn by OD in the striatum and neocortical areas (i.e., cingulate, motor, and somatosensory cortices) of Ctrl- and LB-SG-injected mice, relative to vehicle-injected animals, at 6 months post-inoculations. For striatum, Ctrl: n = 7; mean = 106.1; SD = 10.69; SEM = 4.041; LB-SG: n = 10; mean = 101.5; SD = 13.6; SEM = 4.3; p = 0.47, two-tailed t-test. For cortex, Ctrl: n = 7; mean = 106.9; SD = 16.15; SEM = 6.105; LB-SG: n = 10; mean = 104.9; SD = 12.59; SEM = 3.981; p = 0.773, two-tailed t-test. In all panels, histograms represent average ± standard error of the mean (SEM). Vehicle-injected mice, n = 8–10. Scale bars, 30 μm (a) and 500 μm (b)