title: The 1A4 molecule (CD27) is involved in T cell activation.
abstract: We developed a new mAb, anti-1A4, which recognizes an epitope on the CD27 molecule distinct from those recognized by several known anti-CD27 mAb. Although it has been suggested that the CD27 molecule is a T cell activation Ag, there was little direct evidence that the structure was involved in the T cell activation process. In this study, we showed that anti-1A4 inhibited anti-CD2, anti-CD3, mitogens, or soluble Ag-induced T cell proliferation as well as PWM-driven B cell IgG synthesis. Interestingly, anti-1A4 inhibited IL-2 secretion without affecting IL-2R expression. In addition, pretreatment of T cells with anti-1A4 inhibited the normally sustained intracellular calcium mobilization seen after triggering of T cells via the CD2 or CD3 pathways. Thus, binding of anti-1A4 to the CD27 molecule appears to induce a negative effect on T cell activation. This may be due to either a direct signal to T cells or the blocking of an interaction between T cells and accessory cells or both. These findings support the notion that the CD27 molecule plays an integral role in the process of T cell activation.
authors.affiliation: Division of Tumor Immunology, Dana-Farber Cancer Institute, Boston, MA 02115.
authors.forename: K
authors.initials: K
authors.lastname: Sugita
authors.forename: Y
authors.initials: Y
authors.lastname: Torimoto
authors.forename: Y
authors.initials: Y
authors.lastname: Nojima
authors.forename: J F
authors.initials: JF
authors.lastname: Daley
authors.forename: S F
authors.initials: SF
authors.lastname: Schlossman
authors.forename: C
authors.initials: C
authors.lastname: Morimoto
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000276:immunology / Q000502:physiology*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology / Q000502:physiology*; D018801:CD2 Antigens; D002118:Calcium / Q000378:metabolism; D000939:Epitopes / Q000032:analysis; D007376:Interleukin-2 / Q000378:metabolism; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D011971:Receptors, Immunologic / Q000502:physiology; D015375:Receptors, Interleukin-2 / Q000032:analysis; D013601:T-Lymphocytes / Q000276:immunology*; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D000939:Epitopes; D007376:Interleukin-2; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7; D002118:Calcium