《病原生物与免疫学实验:免疫学概述》由会员分享,可在线阅读,更多相关《病原生物与免疫学实验:免疫学概述(26页珍藏版)》请在金锄头文库上搜索。
1、Immunity1.Immunity: refers to all mechanisms used by the body as protection against environmental agents that are foreign to the body. (to recognize and eliminate foreign substances)2.Agents:microorganisms (viruses, bacteria etc) and their products, foods, chemicals, pollen, tumor cells, etc.3.Immun
2、e system: immune tissues and organs, immune cells, immune moleculesIntroductionThree functions of immune system: (1) immunologic defence (2) immunologic surveillance (3) immunologic homeostasisThe Danger Model: A RenewedSense of SelfPolly MatzingerThe Self-Nonself ModelsThe Infectious-Nonself (INS)
3、ModelThe Danger ModelImmune ResponseIntroduction Innate immune response natural immune response non-specific immune response Adaptive immune response acquired immune response specific immune responseInnate immunityIt refers to any inborn immunity that is already present the first time a pathogen is
4、encountered.It does not require prior exposure and is not modified significantly by repeated exposures to the pathogen over the life of an individual.IntroductionThe principal mechanisms of innate and adaptive immunityInnate immunity mechanism of recognitionPathogen associated molecules patterns(PAM
5、Ps): LPS, DNA, RNA, ProteinDanger-associated molecular patterns (DAMPS): DNA, HSPPattern recognition receptors (PRR): Toll-like receptor(TLR) ,C-lectin recptor(CLR),RIG-I-Like recptor(RLR),NOD-like Receptor(NLR)Toll-like receptor (TLR)TLRInnate immune responseIntroductionMacrophage Attacking E.coli
6、Adaptive immune responseThe T cells and B cells in the body recognize the antigen and, in turn, become activated. The activated lymphocytes then proliferate and carry out their specific effector functions. Types of adaptive immunityTwo types of adaptive immunityHumoral immunity: mediated by B cells
7、and defense against extracellular microbes. Cell-mediated immunity: mediated by T cells and defense against intracellular microbes.Cell-mediated immunity:Phagocytosis (cellular eating)cytotoxcity (cellular killing)Humoral immunity:antibodies: (also called immunoglobulin) proteins secreted by B cells
8、 that bind directly and specifically to pathogens. Antibodies target pathogens by marking them for destruction by other components of the immune system. complement: group of serum proteins that can directly kill pathogens.Immune Effector Mechanisms 2005 Elsevier Types of adaptive immunity.Adaptive i
9、mmune responseIntroduction1. The activation of lymphocytes antigen interacts with specific receptors: B cell- BCR (B cell receptor): membrane Ig T cell- TCR (T cell receptor), co-stimulatory signal2. Proliferation and differentiation of lymphocytes B cell-cytokines (IL-4,etc.) T cell-Antigen-TCR; co
10、-stimulatory signal; cytokines(IL-2,IL-7,IL-15)3. Effector cells and their functions B cell-Antibody; T cell-Th, CTL4. Memory cellsDownloaded from: StudentConsult (on 31 May 2006 05:26 PM) 2005 Elsevier Downloaded from: StudentConsult (on 31 May 2006 05:26 PM) 2005 Elsevier Links between innate and
11、adaptive immunityThe clonal selection hypothesisThe Nobel Prize in Physiology or Medicine 1987for his discovery of the genetic principle for generation of antibody diversitySusumu Tonegawa(利川根进)(利川根进) Gene rearrangement of Ig Gene rearrangement of Ig Most blood cells act to fight infection.Adaptive immunityInnate immunityBlood cells lineages.Properties of TH1, TH2, and TH17 subsets of CD4+ helper T cells. B LymphocytesIntroduction