Figure 9.

Representative examples of medullary acid-α glucosidase (GAA) immunostaining 12 months following intralingual injection with AAV1-hGAA in a Gaa^−/− mouse. Positive immunostaining for GAA is restricted to the XII motor nucleus in the rostral medulla at 12 months following intralingual injection of (a) AAV1-hGAA. A representative section caudal to the XII motor nucleus with no GAA labeling is shown in (b). Panels c and d show examples of “clustering” of GAA-positive motoneurons which was typical at 12 months postinjection. The contrast in the histological appearance of GAA-positive versus negative cells is illustrated in (e–f). The GAA-positive motoneurons have a central nucleus without evidence of vacuoles. In contrast, cells not expressing GAA (*) in panels e and f have an eccentric nucleus with an enlarged vacuole filled soma. Scale bars = a: 50 µm; b: 200 µm.