title: CD5+ B cells and the immune system.
abstract: The CD5+ B-cell population is prominent in early life and may play a key role in the ontogeny of the immune system. Transplantation studies in mice are in support of CD5+ B cells as a separate lineage from CD5- B cells. In both mice and men there is evidence in favour of CD5 being an activation antigen rather than a lineage marker, but the jury is still out! The frequency of CD5+ B cells appears to be under genetic influence. CD5+ B cells are receptive to many cytokines including IL-2 and IL-5 and themselves produce a number of cytokines especially IL-10. The function of the CD5 molecule on B cells is presently unknown but it might be involved in interaction with CD72 on other B cells. CD5+ B cells generally utilise minimally mutated germ-line genes and produce low avidity auto- and polyreactive antibodies (natural antibodies) generally of the IgM class.
authors.affiliation: Department of Immunology, University College of London Medical School, U.K.
authors.forename: P M
authors.initials: PM
authors.lastname: Lydyard
authors.forename: A
authors.initials: A
authors.lastname: Lamour
authors.forename: L E
authors.initials: LE
authors.lastname: MacKenzie
authors.forename: C
authors.initials: C
authors.lastname: Jamin
authors.forename: R A
authors.initials: RA
authors.lastname: Mageed
authors.forename: P
authors.initials: P
authors.lastname: Youinou
mesh_terms: D000818:Animals; D000917:Antibody Formation / Q000502:physiology; D017951:Antigen Presentation; D015703:Antigens, CD / Q000097:blood*; D001323:Autoantibodies / Q000096:biosynthesis; D016175:B-Lymphocyte Subsets / Q000502:physiology*; D015415:Biomarkers; D018956:CD5 Antigens; D005803:Genes, Immunoglobulin; D006801:Humans; D007108:Immune Tolerance; D007130:Immunoglobulin Idiotypes / Q000276:immunology; D017634:Self Tolerance
chemical_list: D015703:Antigens, CD; D001323:Autoantibodies; D015415:Biomarkers; D018956:CD5 Antigens; D007130:Immunoglobulin Idiotypes