Marginal zone B-cell

Marginal zone B cells are noncirculating mature B cells that in humans segregate anatomically into the marginal zone (MZ) of the spleen[1] and certain other types of lymphoid tissue.[2] The spleen's marginal zone contains multiple subtypes of macrophages and dendritic cells interlaced with the MZ B cells; it is not fully formed until 2 to 3 weeks after birth in rodents and 1 to 2 years in humans.[3] The MZ B cells within this region typically express high levels of IgM, CD21, CD1, CD9 with low to negligible levels of secreted-IgD, CD23, CD5, and CD11b that help to distinguish them phenotypically from follicular (FO) B cells and B1 B cells. In humans the splenic marginal zone B cells have evidence of somatic hypermutation in their immunoglobulin genes, indicating that they have been generated through a germinal centre reaction to become memory cells. [4] In humans, but not rodents, marginal zone B cells are also located in the inner wall of the subcapsular sinus of lymph nodes, the epithelium of tonsillar crypts, and the sub-epithelial area of mucosa-associated lymphoid tissues including the sub-epithelial dome of intestinal Peyer's patches.[2]

Similar to B1 B cells, MZ B cells can be rapidly recruited into the early adaptive immune responses in a T cell independent manner.[5] The MZ B cells are especially well positioned as a first line of defense against systemic blood-borne antigens that enter the circulation and become trapped in the spleen.[6] It is believed they are especially reactive to bacterial cell wall components and self-antigens which are the products of aging.[5] MZ B cells also display a lower activation threshold than their FO B cell counterparts with heightened propensity for plasma cell differentiation that contributes further to the accelerated primary antibody response.[7]

In specimens where the tyrosine kinase for Pyk-2 has been knocked-out, marginal zone B-cells will fail to develop while B-1 cells will still be present.[5]

MZ B-cells are the only B-cells dependent on NOTCH2 signaling for proliferation.[5]

Marginal zone B cells are the malignant cells in marginal zone lymphomas, a heterogeneous group of generally indolent lymphomas.[8]

References
  1. Martin F, Kearney JF. Marginal-zone B cells. Nat Rev Immunol. 2002;2(5):323–335.
  2. Cerutti A, Cols M, Puga I (February 2013). "Marginal zone B cells: virtues of innate-like antibody-producing lymphocytes". Nature Reviews. Immunology. 13 (2): 118–32. doi:10.1038/nri3383. PMC 3652659. PMID 23348416.
  3. MacLennan IC, Bazin H, Chassoux D, et al. Comparative analysis of the development of B cells in marginal zones and follicles. Adv Exp Med Biol. 1985;186:139–144.
  4. Dunn-Walters, DK; Isaacson, PG; Spencer, J (1995). "Analysis of mutations in immunoglobulin heavy chain variable region genes of microdissected marginal zone (MGZ) B cells suggests that the MGZ of human spleen is a reservoir of memory B cells". J. Exp. Med. 182: 559–566. doi:10.1084/jem.182.2.559. PMC 2192131.
  5. Hardy, Richard (2008). "Chapter 7: B Lymphocyte Development and Biology". In Paul, William (ed.). Fundamental Immunology (Book) (6th ed.). Philadelphia: Lippincott Williams & Wilkins. pp. 237–269. ISBN 0-7817-6519-6.
  6. Balazs M, Martin F, Zhou T, et al. "Blood dendritic cells interact with splenic marginal zone B cells to initiate T-independent immune responses". Immunity. 2002;17(3):341–352.
  7. Lopes-Carvalho T, Foote J, Kearney JF. Marginal zone B cells in lymphocyte activation and regulation. Curr Opin Immunol. 2005; 17(3):244–250
  8. Bron D, Meuleman N (September 2019). "Marginal zone lymphomas: second most common lymphomas in older patients". Current Opinion in Oncology. 31 (5): 386–393. doi:10.1097/CCO.0000000000000554. PMID 31246587.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.