title: A single peptide from the major outer membrane protein of Chlamydia trachomatis elicits T cell help for the production of antibodies to protective determinants.
abstract: The protective immune response to infection with Chlamydia trachomatis is associated with antibody reactivity to serovar-specific determinants on the major outer membrane protein (MOMP). Because this immunity is T cell dependent, it is essential to define those Th cell determinants that promote natural boosting of the protective antibody response. The gene for MOMP of serovar B was separated into nine overlapping fragments that represent the five C and four V regions. These fragments were expressed as fusion peptides with GST and used to identify the regions of the MOMP that contain T cell determinants recognized in BALB/c mice. We identified peptides that elicit a T cell response to Chlamydia by immunizing mice with the fusion peptides and testing the proliferative response of T cells in vitro to intact organism. For analysis of determinants seen after infection, animals were inoculated with live organism and the T cell proliferative response to each fusion peptide was measured in vitro. In contrast to proliferative analysis in which several regions of the MOMP elicited T cell responses, functional analysis demonstrated that a single fusion peptide, containing V segment three, elicited T cell help in vivo for the production of high titered antisera, specific for protective determinants on the MOMP.
authors.affiliation: Department of Biomedical and Environmental Health Sciences, University of California, Berkeley 94720.
authors.forename: J E
authors.initials: JE
authors.lastname: Allen
authors.forename: R M
authors.initials: RM
authors.lastname: Locksley
authors.forename: R S
authors.initials: RS
authors.lastname: Stephens
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000276:immunology*; D001483:Base Sequence; D002692:Chlamydia trachomatis / Q000276:immunology*; D000939:Epitopes; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009841:Oligonucleotides / Q000737:chemistry; D010455:Peptides / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000276:immunology / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D000939:Epitopes; D009841:Oligonucleotides; D010455:Peptides; D011993:Recombinant Fusion Proteins