交通大学生物科技系.pptVIP

* * * * * * * * * * * * * * * * POPI: Predicting immunogenicity of MHC class I binding peptides by mining informative physicochemical properties Prof. Shinn-Ying Ho 何信瑩 教授 Institute of Bioinformatics, Department of Biological Science and Technology, National Chiao Tung University 交通大學生物科技系、生物資訊研究所 Chun-Wei Tung and Shinn-Ying HoBioinformatics, vol. 23(8), pp. 942-949, 2007 Guideline Introduction Motivation Materials Human MHC class I binding peptides Physicochemical properties Methods Support vector machine (SVM) Orthogonal experimental design (OED) Inheritable bi-objective genetic algorithm (IBCGA) Results Conclusions Introduction Antigen processing pathway (抗原處理路徑) immune surveillance (免疫監督) by cytotoxic T lymphocytes (CTLs, 細胞毒性T淋巴球) http://www.jr2.ox.ac.uk/ndm/andy/fig12._files/image002.jpg (Dr. Andy Sewell, The T cell Molecular Modulation Group, University of Oxford); Antigen processing pathway (previous works) Step 1- Proteolysis by proteasome (蛋白酶體將抗原水解) Step 2- Transportation of peptides to endoplasmic reticulum (內質網) by TAP (Transporter associated with Antigen Processing) Step 3- Presentation of peptides to cell surface by MHC class I (Major Histocompatibility Complex, 主要組織相容性複合體) Immune surveillance Induction of immune response (this study) Introduction Factors influence peptide immunogenicity Intrinsic factors e.g. physicochemical properties Extrinsic factor e.g. host immunoglobulin repertoire (免疫球蛋白) The definition of peptide immunogenicity The immunogenicity of a peptide is determined by measuring the concentration of peptides giving 50% of maximum specific lysis by CTLs of target cells displaying the peptide, and is given a descriptive value (high, moderate, little and none). Motivation Previous studies only work on prediction of antigen processing pathway (step 1-3) However, peptide immunogenicity is important to: Understand immune system Develop vaccines Goal Use physicochemical properties to predict peptide immunogenicity Materia