title: The function and regulation of immunoglobulin D.
abstract: Recent discoveries of IgD in ancient vertebrates suggest that IgD has been preserved in evolution from fish to human for important immunological functions. A non-canonical form of class switching from IgM to IgD occurs in the human upper respiratory mucosa to generate IgD-secreting B cells that bind respiratory bacteria and their products. In addition to enhancing mucosal immunity, IgD class-switched B cells enter the circulation to 'arm' basophils and other innate immune cells with secreted IgD. Although the nature of the IgD receptor remains elusive, cross-linking of IgD on basophils stimulates release of immunoactivating, proinflammatory and antimicrobial mediators. This pathway is dysregulated in autoinflammatory disorders such as hyper-IgD syndrome, indicating that IgD orchestrates an ancestral surveillance system at the interface between immunity and inflammation.
authors.affiliation: Immunology Institute, Department of Medicine, Mount Sinai School of Medicine, One Gustave, L. Levy Place, New York, NY 10029, USA.
authors.forename: Kang
authors.initials: K
authors.lastname: Chen
authors.forename: Andrea
authors.initials: A
authors.lastname: Cerutti
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D019143:Evolution, Molecular; D006801:Humans; D017578:Immunoglobulin Class Switching; D007072:Immunoglobulin D / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D007072:Immunoglobulin D