title: Role of HLA-DP in the Presentation of Epitopes from the Truncated Bacterial PE38 Immunotoxin.
abstract: Identification of helper T-cell epitopes is important in many fields of medicine. We previously used an experimental approach to identify T-cell epitopes in PE38, a truncated bacterial toxin used in immunotoxins. Here, we evaluated the ability of antibodies to DR, DP, or DQ to block T-cell responses to PE38 epitopes in 36 PBMC samples. We predicted the binding affinities of peptides to DR, DP, and DQ alleles using computational tools and analyzed their ability to predict the T-cell epitopes. We found that HLA-DR is responsible for 65% of the responses, DP 24%, and DQ 4%. One epitope that is presented in 20% of the samples (10/50) is entirely DP restricted and was not predicted to bind to DR or DP reference alleles using binding algorithms. We conclude that DP has an important role in helper T-cell response to PE38.
authors: Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Room 5106, Bethesda, Maryland, 20892-4264, USA.
authors: Ronit
authors: R
authors: Mazor
authors: Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Room 5106, Bethesda, Maryland, 20892-4264, USA.
authors: Selamawit
authors: S
authors: Addissie
authors: Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Room 5106, Bethesda, Maryland, 20892-4264, USA.
authors: Youjin
authors: Y
authors: Jang
authors: Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Room 5106, Bethesda, Maryland, 20892-4264, USA.
authors: Chin-Hsien
authors: CH
authors: Tai
authors: Experimental Transplantation and Immunology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA.
authors: Jeremy
authors: J
authors: Rose
authors: Experimental Transplantation and Immunology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA.
authors: Fran
authors: F
authors: Hakim
authors: Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Room 5106, Bethesda, Maryland, 20892-4264, USA. pastani@mail.nih.gov.
authors: Ira
authors: I
authors: Pastan
mesh_terms: D000465:Algorithms; D000483:Alleles; D000595:Amino Acid Sequence; D001427:Bacterial Toxins / Q000276:immunology*; D001665:Binding Sites; D002478:Cells, Cultured; D018984:Epitopes, T-Lymphocyte / Q000235:genetics / Q000276:immunology*; D005434:Flow Cytometry; D005802:Genes, MHC Class II; D006682:HLA-DP Antigens / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D006801:Humans; D000922:Immunotoxins / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008213:Lymphocyte Activation; D010455:Peptides / Q000737:chemistry* / Q000276:immunology
chemical_list: D001427:Bacterial Toxins; D018984:Epitopes, T-Lymphocyte; D006682:HLA-DP Antigens; D000922:Immunotoxins; D010455:Peptides
keywords: DP; HLA class II; MHC class II; T-cell epitopes; epitope prediction; in silico