Both humoral and cell-mediated immunity are involved and 10% of patients with CIDP are seropositive for IgG4 and IgM auto-Abs mainly against neurofascin (NF) isoforms (NF155, NF140, NF186) or contactin-1 (CNTN1); all of them are proteins in nodal and paranodal Ranvier regions. The gene discussed is CNTN1; the disease is chronic inflammatory demyelinating polyradiculoneuropathy.