title: Essential immunoregulatory role for BCAP in B cell development and function.
abstract: BCAP was recently cloned as a binding molecule to phosphoinositide 3-kinase (PI3K). To investigate the role of BCAP, mutant mice deficient in BCAP were generated. While BCAP-deficient mice are viable, they have decreased numbers of mature B cells and B1 B cell deficiency. The mice produce lower titers of serum immunoglobulin (Ig)M and IgG3, and mount attenuated responses to T cell--independent type II antigen. Upon B cell receptor cross-linking, BCAP-deficient B cells exhibit reduced Ca(2+) mobilization and poor proliferative responses. These findings demonstrate that BCAP plays a pivotal immunoregulatory role in B cell development and humoral immune responses.
authors.affiliation: Department of Molecular Genetics, Institute for Liver Research, Kansai Medical University, Moriguchi, Osaka, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Yamazaki
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Takeda
authors.forename: Kumiko
authors.initials: K
authors.lastname: Gotoh
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takeshima
authors.forename: Shizuo
authors.initials: S
authors.lastname: Akira
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kurosaki
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D002352:Carrier Proteins / Q000502:physiology*; D007527:Isoenzymes / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051966:Phospholipase C gamma; D011947:Receptors, Antigen, B-Cell / Q000502:physiology; D010738:Type C Phospholipases / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D007527:Isoenzymes; C487978:Pik3ap1 protein, mouse; D011947:Receptors, Antigen, B-Cell; D019869:Phosphatidylinositol 3-Kinases; D010738:Type C Phospholipases; D051966:Phospholipase C gamma; D002118:Calcium