title: Cutting edge: BAFF regulates CD21/35 and CD23 expression independent of its B cell survival function.
abstract: Herein we demonstrate that B cell-activating factor of the TNF family (BAFF), a B cell survival factor, also regulates CD21/35 and CD23 expression. BAFF blockade in wild-type mice down-modulates CD21/35 and CD23 on B cells while survival remains intact, and BAFF exposure causes elevated CD21/35 and CD23 expression. Similar down-modulation is observed in bcl-2-transgenic mice treated with a BAFF inhibitor. This is the first evidence that BAFF has a function independent of B cell survival. Reports using CD21/35 and CD23 expression to assess splenic B cell subsets in BAFF-null mice concluded a lack of B cells beyond the immature stage. Since CD21/35 and CD23 are inadequate for delineating B cell subpopulations in BAFF-null mice, we used expression of BAFF-R and several B cell markers to identify more mature splenic B cells in these mice. These data broaden our understanding of BAFF function and correct the view that BAFF-null mice lack mature B cells.
authors.affiliation: Department of Immunology and Inflammation, Biogen Idec Inc., 12 Cambridge Center, Cambridge, MA 02142, USA.
authors.forename: Leonid
authors.initials: L
authors.lastname: Gorelik
authors.forename: Anne H
authors.initials: AH
authors.lastname: Cutler
authors.forename: Greg
authors.initials: G
authors.lastname: Thill
authors.forename: Steven D
authors.initials: SD
authors.lastname: Miklasz
authors.forename: Dianna E
authors.initials: DE
authors.lastname: Shea
authors.forename: Christine
authors.initials: C
authors.lastname: Ambrose
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Bixler
authors.forename: Lihe
authors.initials: L
authors.lastname: Su
authors.forename: Martin L
authors.initials: ML
authors.lastname: Scott
authors.forename: Susan L
authors.initials: SL
authors.lastname: Kalled
mesh_terms: D000818:Animals; D053264:B-Cell Activating Factor; D053265:B-Cell Activation Factor Receptor; D016175:B-Lymphocyte Subsets / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D002470:Cell Survival / Q000235:genetics / Q000276:immunology; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007072:Immunoglobulin D / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D008822:Mice, Transgenic; D017463:Receptors, Complement 3b / Q000096:biosynthesis*; D017464:Receptors, Complement 3d / Q000096:biosynthesis*; D017455:Receptors, IgE / Q000096:biosynthesis*; D018124:Receptors, Tumor Necrosis Factor / Q000096:biosynthesis; D013154:Spleen / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D015854:Up-Regulation / Q000235:genetics / Q000276:immunology
chemical_list: D053264:B-Cell Activating Factor; D053265:B-Cell Activation Factor Receptor; D007072:Immunoglobulin D; D007075:Immunoglobulin M; D008565:Membrane Proteins; D017463:Receptors, Complement 3b; D017464:Receptors, Complement 3d; D017455:Receptors, IgE; D018124:Receptors, Tumor Necrosis Factor; C435926:TNFRSF13C protein, human; C505719:TNFSF13B protein, human; C486662:Tnfrsf13c protein, mouse; C505720:Tnfsf13b protein, mouse; D014409:Tumor Necrosis Factor-alpha