Identifying MHC Class I Epitopes by Predicting the TAP Transport Efficiency of Epitope Precursors

We are able to make reliable predictions of the efficiency with which peptides of arbitrary lengths will be transported by TAP. The pressure exerted by TAP on Ag presentation thus can be assessed by checking to what extent MHC class I (MHC-I)-presented epitopes can be discriminated from random peptides on the basis of predicted TAP transport efficiencies alone. Best discriminations were obtained when N-terminally prolonged epitope precursor peptides were included and the contribution of the N-terminal residues to the score were down-weighted in comparison with the contribution of the C terminus. We provide evidence that two factors may account for this N-terminal down-weighting: 1) the uncertainty as to which precursors are used in vivo and 2) the coevolution in the C-terminal sequence specificities of TAP and other agents in the pathway, which may vary among the various MHC-I alleles. Combining predictions of MHC-I binding affinities with predictions of TAP transport efficiency led to an improved identification of epitopes, which was not the case when predictions of MHC-I binding affinities were combined with predictions of C-terminal cleavages made by the proteasome.

[1]  K. Parker,et al.  Scheme for ranking potential HLA-A2 binding peptides based on independent binding of individual peptide side-chains. , 1994, Journal of immunology.

[2]  Günter J. Hämmerling,et al.  Selectivity of MHC-encoded peptide transporters from human, mouse and rat , 1994, Nature.

[3]  R. Tampé,et al.  A sequential model for peptide binding and transport by the transporters associated with antigen processing. , 1994, Immunity.

[4]  A Sette,et al.  The peptide-binding motif for the human transporter associated with antigen processing , 1995, The Journal of experimental medicine.

[5]  Andrew P. Bradley,et al.  The use of the area under the ROC curve in the evaluation of machine learning algorithms , 1997, Pattern Recognit..

[6]  A. Goldberg,et al.  Two distinct proteolytic processes in the generation of a major histocompatibility complex class I-presented peptide. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[7]  S Uebel,et al.  Recognition principle of the TAP transporter disclosed by combinatorial peptide libraries. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[8]  P. van Endert,et al.  Absence of functional relevance of human transporter associated with antigen processing polymorphism for peptide selection. , 1997, Journal of immunology.

[9]  V Brusic,et al.  Relationship between peptide selectivities of human transporters associated with antigen processing and HLA class I molecules. , 1998, Journal of immunology.

[10]  Vladimir Brusic,et al.  A neural network model approach to the study of human TAP transporter , 1998, Silico Biol..

[11]  P. van Endert,et al.  Substrate selection by transporters associated with antigen processing occurs during peptide binding to TAP. , 1998, Molecular immunology.

[12]  P. Kloetzel,et al.  A theoretical approach towards the identification of cleavage-determining amino acid motifs of the 20 S proteasome. , 1999, Journal of molecular biology.

[13]  F. Chisari,et al.  Human Transporters Associated with Antigen Processing (Taps) Select Epitope Precursor Peptides for Processing in the Endoplasmic Reticulum and Presentation to T Cells , 1999, The Journal of experimental medicine.

[14]  S Uebel,et al.  Specificity of the proteasome and the TAP transporter. , 1999, Current opinion in immunology.

[15]  A. Goldberg,et al.  The Sizes of Peptides Generated from Protein by Mammalian 26 and 20 S Proteasomes , 1999, The Journal of Biological Chemistry.

[16]  P. Paz,et al.  Discrete proteolytic intermediates in the MHC class I antigen processing pathway and MHC I-dependent peptide trimming in the ER. , 1999, Immunity.

[17]  A. Goldberg,et al.  Degradation of cell proteins and the generation of MHC class I-presented peptides. , 1999, Annual review of immunology.

[18]  H. Rammensee,et al.  SYFPEITHI: database for MHC ligands and peptide motifs , 1999, Immunogenetics.

[19]  Christina Kuttler An Algorithm for the Prediction of Proteasomal Cleavages , 2000, German Conference on Bioinformatics.

[20]  Taku Suto,et al.  An automated prediction of MHC class I-binding peptides based on positional scanning with peptide libraries , 2000, Immunogenetics.

[21]  Ferry Ossendorp,et al.  Efficient Identification of Novel Hla-A*0201–Presented Cytotoxic T Lymphocyte Epitopes in the Widely Expressed Tumor Antigen Prame by Proteasome-Mediated Digestion Analysis , 2001, The Journal of experimental medicine.

[22]  K. Hadeler,et al.  PAProC: a prediction algorithm for proteasomal cleavages available on the WWW , 2001, Immunogenetics.

[23]  N. Shastri,et al.  ER aminopeptidases generate a unique pool of peptides for MHC class I molecules , 2001, Nature Immunology.

[24]  A. Goldberg,et al.  The importance of the proteasome and subsequent proteolytic steps in the generation of antigenic peptides. , 2002, Molecular immunology.

[25]  Hermann-Georg Holzhütter,et al.  Assessment of proteasomal cleavage probabilities from kinetic analysis of time-dependent product formation. , 2002, Journal of molecular biology.

[26]  Akira Hattori,et al.  An IFN-γ–induced aminopeptidase in the ER, ERAP1, trims precursors to MHC class I–presented peptides , 2002, Nature Immunology.

[27]  S. Brunak,et al.  Prediction of proteasome cleavage motifs by neural networks. , 2002, Protein engineering.

[28]  William H. Press,et al.  Numerical recipes in C , 2002 .

[29]  N. Shastri,et al.  Producing nature's gene-chips: the generation of peptides for display by MHC class I molecules. , 2002, Annual review of immunology.

[30]  N. Shastri,et al.  ERAAP customizes peptides for MHC class I molecules in the endoplasmic reticulum , 2002, Nature.

[31]  John Sidney,et al.  Examining the independent binding assumption for binding of peptide epitopes to MHC-I molecules , 2003, Bioinform..