title: BTNL8, a butyrophilin-like molecule that costimulates the primary immune response.
abstract: The role of the B7 family molecules in the regulation of the immune response is well documented. A large body of experimental evidence indicates that costimulatory molecules such as B7-1, B7-2, B7-DC, B7-H1, B7-H2, B7-H3 and B7-H4 are critical for initiation, maintenance and down-regulation of the immune response. However the immunological function of butyrophilin (BTN)-like molecules, which are a part of the expanded B7 family, is not known. Here, we demonstrate that the extracellular portion of human BTNL8 can augment Ag-induced activation of T lymphocytes. BTNL8 has two alternatively spliced forms: B7-like and BTN-like. Both isoforms of BTNL8 were expressed concurrently in various human tissues. A putative BTNL8 receptor was detected only on resting T lymphocytes. Administration of BTNL8Ig fusion protein into mice promoted production of Ag-specific IgG during the primary, but not the secondary immune responses. BTNL8 may therefore play an essential role in priming of naïve T lymphocytes.
authors.affiliation: University of Maryland School of Medicine, Department of Otorhinolaryngology-Head and Neck Surgery, Baltimore, MD 21201, USA; CuraGen Corporation, Branford, CT 06405, USA. Electronic address: chapoval@comcast.net.
authors.forename: Andrei I
authors.initials: AI
authors.lastname: Chapoval
authors.forename: Glennda
authors.initials: G
authors.lastname: Smithson
authors.forename: Linda
authors.initials: L
authors.lastname: Brunick
authors.forename: Mehdi
authors.initials: M
authors.lastname: Mesri
authors.forename: Ferenc L
authors.initials: FL
authors.lastname: Boldog
authors.forename: David
authors.initials: D
authors.lastname: Andrew
authors.forename: Nikolai V
authors.initials: NV
authors.lastname: Khramtsov
authors.forename: Elena A
authors.initials: EA
authors.lastname: Feshchenko
authors.forename: Gary C
authors.initials: GC
authors.lastname: Starling
authors.forename: Peter S
authors.initials: PS
authors.lastname: Mezes
mesh_terms: D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D000941:Antigens / Q000276:immunology*; D060887:B7 Antigens / Q000235:genetics / Q000276:immunology; D000071797:Butyrophilins; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D005260:Female; D057809:HEK293 Cells; D006801:Humans; D007074:Immunoglobulin G / Q000235:genetics / Q000276:immunology; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000276:immunology; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000235:genetics / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D059467:Transcriptome / Q000235:genetics / Q000276:immunology
chemical_list: D000941:Antigens; D060887:B7 Antigens; C584968:BTNL8 protein, human; D000071797:Butyrophilins; D007074:Immunoglobulin G; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D020033:Protein Isoforms; D011993:Recombinant Fusion Proteins
keywords: BTN; Cell activation; Costimulation; Cytokines; T cells; butyrophilin