title: Synthetic peptides based on Chlamydia trachomatis antigens identify cytotoxic T lymphocyte responses in subjects from a trachoma-endemic population.
abstract: CD8+ cytotoxic T lymphocytes (CTL) recognize peptide antigens in the context of class I MHC antigen molecules. To identify peptides capable of eliciting anti-Chlamydia trachomatis CTL responses, 13 synthetic peptides conforming to human leucocyte antigen (HLA)-B8- or -B35-predicted binding motifs were synthesized using sequences based on C. trachomatis major outer membrane protein (MOMP) and heat shock protein 60 (hsp60). Two of 11 HLA-B35-predicted binding peptides were able to stabilize HLA-B35 in an in vitro binding assay. All peptides were tested in CTL assays using peripheral blood mononuclear cells (PBMC) isolated from 26 HLA-B8 or -B35 individuals resident in a trachoma-endemic community. Responses to MOMP and hsp60 peptides were identified in a minority of both HLA-B8 and -B35 individuals. Two of 12 HLA-B8 subjects responded to MOMP and 1/13 to hsp60 peptides. Responses in HLA-B35 subjects were similar, 1/13 subjects responding to MOMP and 2/13 to hsp60 peptides. CTL responses were observed only in children resolving current infection and in adults without scarring of the conjunctiva. These results suggest that anti-chlamydial CTL occur at low levels in peripheral blood, but may be important in the resolution of naturally acquired human ocular chlamydial infection.
authors.affiliation: Department of Clinical Sciences, London School of Hygiene and Tropical Medicine, UK.
authors.forename: M J
authors.initials: MJ
authors.lastname: Holland
authors.forename: D J
authors.initials: DJ
authors.lastname: Conway
authors.forename: T J
authors.initials: TJ
authors.lastname: Blanchard
authors.forename: O M
authors.initials: OM
authors.lastname: Mahdi
authors.forename: R L
authors.initials: RL
authors.lastname: Bailey
authors.forename: H C
authors.initials: HC
authors.lastname: Whittle
authors.forename: D C
authors.initials: DC
authors.lastname: Mabey
mesh_terms: D000328:Adult; D000942:Antigens, Bacterial / Q000276:immunology*; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology; D018834:Chaperonin 60 / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D002692:Chlamydia trachomatis / Q000276:immunology*; D015797:HLA-B35 Antigen / Q000378:metabolism; D006801:Humans; D010455:Peptides / Q000138:chemical synthesis* / Q000276:immunology*; D015995:Prevalence; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014141:Trachoma / Q000453:epidemiology* / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D018834:Chaperonin 60; D015797:HLA-B35 Antigen; D010455:Peptides