Fig. 3: Clinical trial meets safety endpoint and shows cell product survival and GDNF production.
a, MRI scans were normal throughout the study for all participants, apart from one with mild increased T2 hyperintensity in the area of the graft, that resolved after surgery. b, Measuring the decline in strength for the quadriceps (knee extension) over time for all participants from both dose cohorts showed that both legs became weaker, at varying rates. c, Although not statistically significant, the largest relative difference in the treated leg compared with the untreated leg in the low-dose cohort occurred at 12 months. The high-dose cohort showed a consistently slower rate of decline in the treated leg at all time points. d, Cell survival was shown in all participants by nested PCR, performed on four quadrants of the spinal cord for dorsal (D) and ventral (V) on both the treated (asterisk) and untreated sides. e, Immunohistochemistry revealed GDNF production in all participants. f,g, H&E staining demonstrated an (f) exophytic mass composed of (g) spindle cells arranged in a haphazard and intersecting fascicular growth pattern. h, Immunohistochemistry showed that the spindle cells were positive for S100, consistent with a Schwann cell origin. i, Neurofilament staining showed numerous punctae and irregularly shaped structures consistent with disorganized and regenerative axons mixed with the Schwann cells. j,k, CD34 staining showed (j) normal-appearing blood vessels within the mass and (k) cells were only infrequently Ki67-positive. Scale bar, 1 mm (e, f); 100 µm (g–k).
