title: Neisserial binding to CEACAM1 arrests the activation and proliferation of CD4+ T lymphocytes.
abstract: Infection with Neisseria gonorrhoeae can trigger an intense inflammatory response, yet there is little specific immune response or development of immune memory. In addition, gonorrhea typically correlates with a transient reduction in T lymphocyte counts in blood, and these populations recover when gonococcal infection is resolved. Such observations suggest that the gonococci have a suppressive effect on the host immune response. We report here that N. gonorrhoeae Opa proteins were able to bind CEACAM1 expressed by primary CD4+ T lymphocytes and suppress their activation and proliferation. CEACAM1 bound by gonococcal Opa52 associated with the tyrosine phosphatases SHP-1 and SHP-2, which implicates the receptor's ITIM (immunoreceptor tyrosine-based inhibitory motif) in this effect.
authors.affiliation: Department of Medical Genetics and Microbiology, University of Toronto, Medical Sciences Building Rm. 4381, 1 Kings College Circle, Toronto, Ontario M5S1A8, Canada.
authors.forename: Ian C
authors.initials: IC
authors.lastname: Boulton
authors.forename: Scott D
authors.initials: SD
authors.lastname: Gray-Owen
mesh_terms: D015703:Antigens, CD / Q000032:analysis / Q000502:physiology*; D000943:Antigens, Differentiation / Q000032:analysis / Q000502:physiology*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000502:physiology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D015815:Cell Adhesion Molecules; D016923:Cell Death; D006069:Gonorrhea / Q000276:immunology*; D006801:Humans; D007108:Immune Tolerance; D047908:Intracellular Signaling Peptides and Proteins; D037181:Lectins, C-Type; D008213:Lymphocyte Activation; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases / Q000502:physiology; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D000945:Antigens, Differentiation, T-Lymphocyte; D015815:Cell Adhesion Molecules; D047908:Intracellular Signaling Peptides and Proteins; D037181:Lectins, C-Type; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases; D000099192:CD69 Antigens; C069847:CD66 antigens; C516724:PTPN11 protein, human; C509249:PTPN6 protein, human