title: B and T lymphocyte attenuator exhibits structural and expression polymorphisms and is highly Induced in anergic CD4+ T cells.
abstract: B and T lymphocyte attenuator (BTLA) was initially identified as expressed on Th1 cells and B cells, but recently reported to be expressed by macrophages, dendritic cells, and NK cells as well. To address this discrepancy we generated a panel of BTLA-specific mAbs and characterized BTLA expression under various activation conditions. We report the existence of three distinct BTLA alleles among 23 murine strains, differing both in Ig domain structure and cellular distribution of expression on lymphoid subsets. The BALB/c and MRL/lpr alleles differ at one amino acid residue, but C57BL/6 has nine additional differences and alters the predicted cysteine bonding pattern. The BALB/c BTLA allele is also expressed by B cells, T cells, and dendritic cells, but not macrophages or NK cells. However, C57BL/6 BTLA is expressed on CD11b+ macrophages and NK cells. Finally, in CD4+ T cells, BTLA is expressed most highly following Ag-specific induction of anergy in vivo, and unlike programmed death-1 and CTLA-4, not expressed by CD25+ regulatory T cells. These results clarify discrepancies regarding BTLA expression, suggest that structural and expression polymorphisms be considered when analyzing BTLA in various murine backgrounds, and indicate a possible role in anergic CD4+ T cells.
authors.affiliation: Department of Pathology, Center for Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Hurchla
authors.forename: John R
authors.initials: JR
authors.lastname: Sedy
authors.forename: Maya
authors.initials: M
authors.lastname: Gavrieli
authors.forename: Maya
authors.initials: M
authors.lastname: Gavrielli
authors.forename: Charles G
authors.initials: CG
authors.lastname: Drake
authors.forename: Theresa L
authors.initials: TL
authors.lastname: Murphy
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Murphy
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D001402:B-Lymphocytes / Q000276:immunology; D001483:Base Sequence; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D017635:Clonal Anergy; D006224:Cricetinae; D018076:DNA, Complementary / Q000235:genetics; D015870:Gene Expression; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D019463:Mice, Inbred MRL lpr; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011110:Polymorphism, Genetic; D011971:Receptors, Immunologic / Q000096:biosynthesis / Q000737:chemistry* / Q000172:deficiency / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity
chemical_list: D000911:Antibodies, Monoclonal; C488868:BTLA protein, mouse; D018076:DNA, Complementary; D011971:Receptors, Immunologic