Figure 1.

Schwann cell and axolemmal plasma membrane components within the nodal complex, including glycolipids and cell adhesion molecules act as antigens for autoantibodies in acute and chronic autoimmune neuropathy phenotypes. Antibody binding activates the classical complement cascade resulting in deposition of membrane attack complex (MAC). Calcium influx through MAC pores activates calpain and injures vulnerable membranes whose function depends upon both structural integrity (maintained by glial–axonal adhesion complexes) and ion homeostasis (maintained in part by Nav1.6 and Kv1.1 channels). Noncomplement fixing IgG4 subclass antibodies may disrupt local architecture through blocking effects. Soluble complement products and other inflammatory factors recruit macrophages to the injury site.