Autoantibodies in chronic inflammatory demyelinating polyradiculoneuropathy

Purpose of review Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a heterogeneous disorder that includes diverse clinical presentations and immunopathological mechanisms. Antibodies targeting proteins of the node of Ranvier are present in a subset of CIDP patients. These autoantibodies are pathogenic and associate with specific clinical phenotypes and therapeutic peculiarities. This review summarizes the novel insights that the discovery of novel autoantibodies has brought to the understanding of CIDP. Recent findings Several reports have confirmed the association of the antineurofascin 155 (NF155) antibodies with tremor, ataxia and poor response to IVIG, and with novel pathological features in CIDP patients. The association of nephrotic syndrome with anticontactin 1 (CNTN1) and antinodal neurofascin antibodies has also been described. Also, complement-fixing IgG3 antibodies targeting paranodal proteins have been associated with acute-onset CIDP. Importantly, detection of these autoantibodies has helped selecting CIDP patients for rituximab treatment. Finally, anti-CNTN1 and anti-NF155 antibodies have proven to be the first pathogenic autoantibodies described in CIDP. The discovery of autoantibodies against nodal and paranodal proteins has proven useful in clinical practice, has uncovered novel pathophysiological mechanisms, clinical phenotypes, therapeutic response and prognosis within the CIDP disease spectrum and has boosted the search for other clinically relevant autoantibodies.