Purkinje Cell Cytoplasmic Autoantibody Type 1 Accompaniments:  The Cerebellum and Beyond

Figure 1. Autoimmune myelopathy associated with Purkinje cell cytoplasmic autoantibody type 1 IgG. An axial T2-weighted magnetic resonance imaging scan of the cervical spine (C5 level) reveals bilateral symmetric signal abnormalities in the cord of a 66-year-old woman with motor neuronopathy (patient 7 in Table 1).

Figure 2. Distribution of Purkinje cell cytoplasmic autoantibody type 1 immunoreactivity in mouse neural tissues. Neural-specific staining was ensured by the absorption of bovine liver powder in serum samples (3 times at 1:240 or greater dilution).⁹ The patient's IgG binds to discrete cytoplasmic elements: A, Purkinje (P), molecular (M), and Golgi (G) neurons in the cerebellar cortex; B, cerebellar dentate neurons; C, the myenteric plexus and ganglionic neurons; D, hippocampal neurons; E, midbrain neurons; F, spinal cord neurons (SC), the nerve root (NR), and the dorsal root ganglion (DRG). Scale bars represent 40 μm (A-F).

Figure 3. Representative images from brain and spinal cord findings in 2 autopsied cases (patient 9 [A-F] and patient 10 [G-I]). Neuropathology associated with Purkinje cell cytoplasmic autoantibody type 1 IgG is not restricted to the cerebellum. A, In the cerebellum, prominent loss of neurons in the Purkinje cell (PC) layer, between the molecular layer (ML) and the granular layer (GL), can be seen. White matter (WM) is gliotic (hematoxylin-eosin stain). B, In the cerebellum, Purkinje neurons (PC layer) are absent; WM gliosis is marked, and the GL is largely preserved (hematoxylin-eosin stain). C, In the pons, neuronophagia in the pontine tegmentum can be seen (hematoxylin-eosin stain). D, In the pons, gliosis and perivascular lymphocytic cuffs in the basis pontis can be seen (hematoxylin-eosin stain). E, In the lower medulla, microglial activation and marked gliosis can be seen (hematoxylin-eosin stain). F, In the thoracic cord, anterior horn neuronal loss and marked gliosis can be seen (hematoxylin-eosin stain). G, In the spinal cord (T8), CD3⁺ perivascular and parenchymal lymphocytes can be seen. H, In the spinal cord (T8), many perivascular and parenchymal lymphocytes are CD8⁺. I, In the L1 dorsal root ganglion, dense lymphocytic infiltrates can be seen (hematoxylin-eosin stain). Scale bars represent 250 μm (A-I).