| 1. |
Hidenori Ogata, Anti‐nodal/paranodal antibodies in human demyelinating disorders., Clinical and Experimental Neuroimmunology, doi:10.1111/cen3.12567, 2020.03. |
| 2. |
Jun-Ichi Kira, Ryo Yamasaki, Hidenori Ogata, Anti-neurofascin autoantibody and demyelination, Neurochemistry International, 10.1016/j.neuint.2018.12.011, 2018.12, Demyelination diseases involving the central and peripheral nervous systems are etiologically heterogeneous with both cell-mediated and humoral immunities playing pathogenic roles. Recently, autoantibodies against nodal and paranodal proteins, such as neurofascin186 (NF186), neurofascin155 (NF155), contactin-1 (CNTN1), contactin-associated protein 1 (CASPR1) and gliomedin, have been discovered in not only chronic demyelinating conditions, such as multiple sclerosis (MS) and chronic inflammatory demyelinating polyradiculoneuropathy, but also in acute demyelinating conditions, such as Guillain-Barré syndrome. Only a minority of these patients harbor anti-nodal/paranodal protein antibodies; however, these autoantibodies, especially IgG4 subclass autoantibodies to paranodal proteins, are associated with unique features and these conditions are collectively termed nodopathy or paranodopathy. Establishing a concept of IgG4-related nodopathy/paranodopathy contributes to diagnosis and treatment strategy because IgG4 autoantibody-related neurological diseases are often refractory to conventional immunotherapies. IgG4 does not fix complements, or internalize the target antigens, because IgG4 exists in a monovalent bispecific form in vivo. IgG4 autoantibodies can bock protein-protein interaction. Thus, the primary role of IgG4 anti-paranodal protein antibodies may be blockade of interactions between NF155 and CNTN1/CASPR1, leading to conduction failure, which is consistent with the sural nerve pathology presenting paranodal terminal loop detachment from axons with intact internodes in the absence of inflammation. However, it still remains to be elucidated how these autoantibodies belonging to the same IgG4 subclass can cause each IgG4 autoantibody-specific manifestation. Another important issue is to clarify the mechanism by which IgG4 antibodies to nodal/paranodal proteins emerge. IgG4 antibodies develop on chronic antigenic stimulation and can block antibodies that alleviate allergic inflammation by interfering with the binding of allergen-specific IgE to allergens. Thus, environmental antigens cross-reacting with nodal and paranodal proteins may warrant future study.. |
| 3. |
Hidenori Ogata, Ryo Yamasaki, Anti-neurofascin 155 antibody-related neuropathy, Clinical and Experimental Neuroimmunology, 10.1111/cen3.12444, 2018.02, Chronic inflammatory demyelinating polyneuropathy (CIDP) is an intractable inflammatory disease affecting peripheral nerves. The etiology of CIDP remains to be established, but it is regarded as a mixture of heterogeneous conditions presenting a variety of clinical and electrophysiological manifestations. In recent years, autoantibodies against paranodal cell adhesion molecules, such as neurofascin 155 (NF155), contactin 1 and contactin-associated protein 1, have been detected in subsets of CIDP patients. The clinical characteristics of anti-NF155 antibody-positive CIDP have been delineated, and include a younger onset age, higher frequency of distal muscle weakness, sensory ataxia and tremor, higher cerebrospinal fluid protein levels, more conspicuous demyelination on nerve conduction studies, and nerve root hypertrophy on magnetic resonance neurography, when compared with anti-NF155 antibody-negative CIDP patients. Predominant elevation of immunoglobulin G4 subclass is also a characteristic of this disease. Sural nerve biopsy specimens of anti-NF155 antibody-positive CIDP patients show axo-glial detachment in paranodes without inflammatory cell infiltrates or onion bulb formation. While intravenous immunoglobulin is not as effective as expected against anti-NF155 antibody-positive CIDP patients, other immunotherapies, such as corticosteroids, plasmapheresis and B-cell depletion therapy, seem to be effective. Early diagnosis and treatment is important for preventing secondary axonal degeneration. The present review summarizes the emerging details of anti-NF155 antibody-related neuropathy.. |
