Certainly the success of C1s-targeted CP inhibition in CAD, and nascent studies of C2 inhibition in experimental models and patients with neurologic diseases such as multifocal motor neuropathy (Budding et al., 2022) indicates that IgM and complement fixing isotypes of IgG can play important roles in human autoimmune diseases (Gewurz et al., 1995). The gene discussed is CD40LG; the disease is cold agglutinin disease.