title: Discovery of CD8+ T cell epitopes in Chlamydia trachomatis infection through use of caged class I MHC tetramers.
abstract: Class I MHC tetramers allow direct phenotypic identification of CD8(+) T cell populations, but their production remains laborious. A peptide exchange strategy that employs class I MHC products loaded with conditional ligands (caged MHC molecules) provides a fast and straightforward method to obtain diverse arrays of class I MHC tetramers and facilitates CD8(+) T cell epitope discovery. Here, we describe the development of photocleavable analogs of the FAPGNYPAL (SV9) epitope that bind H-2K(b) and H-2D(b) with full retention of their structural and functional integrity. We ranked all possible H-2K(b) octameric and H-2D(b) nonameric epitopes that span the genome of Chlamydia trachomatis and prepared MHC tetramers from approximately 2,000 of the highest scoring peptides by replacement of the SV9 analog with the peptide of choice. The resulting 2,000-member class I MHC tetramer array allowed the discovery of two variants of an epitope derived from polymorphic membrane protein I (PmpI) and an assessment of the kinetics of emergence and the effector function of the corresponding CD8(+) T cells.
authors.affiliation: Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02139, USA.
authors.forename: Gijsbert M
authors.initials: GM
authors.lastname: Grotenbreg
authors.forename: Nadia R
authors.initials: NR
authors.lastname: Roan
authors.forename: Eduardo
authors.initials: E
authors.lastname: Guillen
authors.forename: Rob
authors.initials: R
authors.lastname: Meijers
authors.forename: Jia-Huai
authors.initials: JH
authors.lastname: Wang
authors.forename: George W
authors.initials: GW
authors.lastname: Bell
authors.forename: Michael N
authors.initials: MN
authors.lastname: Starnbach
authors.forename: Hidde L
authors.initials: HL
authors.lastname: Ploegh
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000528:radiation effects; D002690:Chlamydia Infections / Q000276:immunology*; D002692:Chlamydia trachomatis / Q000276:immunology* / Q000528:radiation effects; D019295:Computational Biology; D018360:Crystallography, X-Ray; D018984:Epitopes, T-Lymphocyte / Q000737:chemistry / Q000276:immunology*; D006183:H-2 Antigens / Q000737:chemistry / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000737:chemistry* / Q000276:immunology*; D008024:Ligands; D008027:Light; D051379:Mice; D008810:Mice, Inbred C57BL; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000276:immunology; D020836:Protein Structure, Quaternary; D015203:Reproducibility of Results; D012995:Solubility / Q000528:radiation effects; D013237:Stereoisomerism
chemical_list: D018984:Epitopes, T-Lymphocyte; D006183:H-2 Antigens; D015395:Histocompatibility Antigens Class I; D008024:Ligands; D010455:Peptides