Effect of intraventricular injection of an anti-Purkinje cell antibody (anti-Yo) in a guinea pig model.

Female guinea pigs had intraventricular injections of either IgG from a patient with paraneoplastic cerebellar degeneration (PCD) and anti-Purkinje cell antibodies (anti-Yo IgG) or control IgG. In animals that received a single injection of control or anti-Yo IgG and were killed at different time intervals, IgG immunoreactivity was present in the cytoplasm of Purkinje cells at 2 h and persisted at 24 h. In guinea pigs injected for 15 days with control or anti-Yo IgG and sacrificed 24 h after the last injection, IgG was detected into the Purkinje cells in both groups, whereas animals killed 7 and 30 days after the last injection had no staining for IgG in the Purkinje cells. Clinical or pathologic evidence of cerebellar involvement was not seen in any of the animals. This study suggests that anti-Yo antibody alone may not be the cause of the Purkinje cell loss in PCD.