title: Transitional B cells: how well are the checkpoints for specificity understood?
abstract: It is crucial for the immune system to minimise the number of circulating mature self-reactive B cells, in order to reduce the potential for the development of autoantibody-related autoimmune diseases. Studies of animal models have identified two major checkpoints that ensure that such cells do not contribute to the naïve B cell repertoire. The first is in the bone marrow as B cells develop and the second is in the spleen; B cells that are released from the bone marrow as transitional B cells go through more stringent selection in the spleen before they develop into mature naïve B cells. Transitional B cells and their maturation have mostly been studied in mice. However, recent studies characterised human transitional B cells and found considerable differences to current models. In this review, we will consider these differences alongside known differences in mouse and human splenic function and ask whether human transitional B cells might develop along a different pathway.
authors.affiliation: Centre for Immunology and Infectious Disease, Barts and The London School of Medicine and Dentistry, Blizard Institute, UK. a.vossenkaemper@qmul.ac.uk
authors.forename: Anna
authors.initials: A
authors.lastname: Vossenkämper
authors.forename: Jo
authors.initials: J
authors.lastname: Spencer
mesh_terms: D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology / Q000378:metabolism; D015551:Autoimmunity / Q000276:immunology; D016175:B-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism; D001853:Bone Marrow / Q000378:metabolism; D002454:Cell Differentiation / Q000276:immunology*; D006801:Humans; D051379:Mice; D008954:Models, Biological; D054448:Precursor Cells, B-Lymphoid / Q000276:immunology / Q000378:metabolism; D015398:Signal Transduction; D013154:Spleen / Q000276:immunology* / Q000378:metabolism
chemical_list: D000944:Antigens, Differentiation, B-Lymphocyte