title: Monoclonal antibodies to B and T lymphocyte attenuator (BTLA) have no effect on in vitro B cell proliferation and act to inhibit in vitro T cell proliferation when presented in a cis, but not trans, format relative to the activating stimulus.
abstract: B and T lymphocyte attenuator (BTLA) is an immunoglobulin superfamily member surface protein expressed on B and T cells. Its ligand, herpesvirus entry mediator (HVEM), is believed to act as a monomeric agonist that signals via the CRD1 of HVEM to inhibit lymphocyte activation: HVEM is also the receptor for lymphotoxin-α and LIGHT, which both bind in the CRD2 and CRD3 domains of the HVEM molecule, and for CD160 which competes with BTLA. We have shown that recombinant HVEM and a panel of different monoclonal antibodies specifically bind murine BTLA on both B and T cells and that some antibodies inhibit anti-CD3ε-induced T cell proliferation in vitro, but only when constrained appropriately with a putatively cross-linking reagent. The antibodies had no significant effect on in vitro T cell proliferation in a mixed lymphocyte reaction (MLR) assay nor on in vitro DO11.10 antigen-induced T cell proliferation. None of these antibodies, nor HVEM-Fc, had any significant effect on in vitro B cell proliferation induced by anti-immunoglobulin M antibodies (±anti-CD40) or lipopolysaccharide. We further elucidated the requirements for inhibition of in vitro T cell proliferation using a beads-based system to demonstrate that the antibodies that inhibited T cell proliferation in vitro were required to be presented to the T cell in a cis, and not trans, format relative to the anti-CD3ε stimulus. We also found that antibodies that inhibited T cell proliferation in vitro had no significant effect on the antibody captured interleukin-2 associated with the in vivo activation of DO11.10 T cells transferred to syngeneic recipient BALB/c mice. These data suggest that there may be specific structural requirements for the BTLA molecule to exert its effect on lymphocyte activation and proliferation.
authors.affiliation: Amgen Inc., Thousand Oaks, CA 91320, USA.
authors.forename: M
authors.initials: M
authors.lastname: Zhang
authors.forename: K
authors.initials: K
authors.lastname: Howard
authors.forename: A
authors.initials: A
authors.lastname: Winters
authors.forename: S
authors.initials: S
authors.lastname: Steavenson
authors.forename: S
authors.initials: S
authors.lastname: Anderson
authors.forename: S
authors.initials: S
authors.lastname: Smelt
authors.forename: G
authors.initials: G
authors.lastname: Doellgast
authors.forename: C
authors.initials: C
authors.lastname: Sheelo
authors.forename: J
authors.initials: J
authors.lastname: Stevens
authors.forename: H
authors.initials: H
authors.lastname: Kim
authors.forename: A
authors.initials: A
authors.lastname: Hamburger
authors.forename: A
authors.initials: A
authors.lastname: Sein
authors.forename: D J
authors.initials: DJ
authors.lastname: Caughey
authors.forename: F
authors.initials: F
authors.lastname: Lee
authors.forename: H
authors.initials: H
authors.lastname: Hsu
authors.forename: G
authors.initials: G
authors.lastname: Siu
authors.forename: F R
authors.initials: FR
authors.lastname: Byrne
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D017252:CD3 Complex / Q000276:immunology; D019013:CD40 Antigens / Q000276:immunology; D003432:Cross-Linking Reagents / Q000737:chemistry; D007075:Immunoglobulin M / Q000276:immunology; D007376:Interleukin-2 / Q000097:blood / Q000276:immunology; D008213:Lymphocyte Activation; D008233:Lymphotoxin-alpha / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D011971:Receptors, Immunologic / Q000037:antagonists & inhibitors* / Q000276:immunology*; D053240:Receptors, Tumor Necrosis Factor, Member 14 / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; C488868:BTLA protein, mouse; D017252:CD3 Complex; D019013:CD40 Antigens; D003432:Cross-Linking Reagents; D007075:Immunoglobulin M; D007376:Interleukin-2; D008233:Lymphotoxin-alpha; D011971:Receptors, Immunologic; D053240:Receptors, Tumor Necrosis Factor, Member 14