抗原和抗体的基础知识.ppt

Chapter 4 Antigens and Antibodies;你需要學習的課題: 1.「好」的免疫原 (immunogen) 有些什麼特質？ 2. 什麼叫做抗原決定區 (epitope)？ B-cell epitope 有何特性？ ********************************************************* 4. 抗體分子的基本構造及各部位的名稱。 5. 抗體的種類、特性及功能。 6. 單株抗體與多株抗體。; Outline 1. Immunogenicity versus antigenicity 2. Epitopes ********************************************************** 3. Basic structure of antibodies (Abs) 4. Ab-binding site 5. Ab-mediated effector functions 6. Ab classes and biological activities 7. Antigenic determinants on immunoglobulins (Ig) 8. The B-cell receptor 9. The Ig superfamily 10. Monoclonal Abs;Immunogenicity vs. Antigenicity;Immunogenicity 免疫性: the ability to induce an Ab and/or cell-mediated immune response Antigenicity 抗原性: the ability to combine specifically with Ab and/or cell-surface receptors (Ig/TCR) ;- Although a substance that induces a specific immune response is usually called an antigen, it is more appropriately called an immunogen. - Although all molecules that have the property of immunogenicity also have the property of antigenicity, the reverse is not true. Some small molecules, called haptens, are antigenic but incapable, by themselves, of inducing a specific immune response. In other words, they lack immunogenicity.;DNP: dinitrophenol;Landsteiner’s work demonstrated both the specificity of the immune system for small structural variations on haptens and the enormous diversity of epitopes that the immune system is capable of recognizing.;Factors That Influence Immunogenicity;Intrinsic properties of an immunogen: - Foreignness - Molecular size - Chemical composition and heterogeneity - Susceptibility to antigen processing and presentation The biological system: - Genotype of the recipient animal - Immunogen dosage and route of administration - Adjuvants; Foreignness Generally, the greater the phylogenetic distance between two species, the greater the struc