免疫学知识概述课件.ppt

1、资料仅供参考,不当之处，请联系改正。The Origin of Immune ConceptThe term “Immunity” = Latin word “Immunitas” = Protection from legal prosecution (Roman senators)Biological definition = Protection from infectious diseases2. The concept of immunity = existed in ancient Greek & Chinese = the experienced view“天花天花”又名痘疮又名

2、痘疮 中国从宋朝起用人痘接种预防天花资料仅供参考,不当之处，请联系改正。The medical view of immunity = Edward Jenner (1796)Observation = Milkmaids generally get No SmallpoxHypothesis = Pus from vaccinia (cowpox) = Protect milkmaids from smallpox Test = Inoculate materials from cowpox pus = Protect a young boy from smallpox (Protective

3、 immunity)The vaccination against smallpoxExudate from a cowpox pustule on the hand of milkmaid Sarah Nelmes was inserted into scratches on the arms of James Phipps, May 14, 1796. 资料仅供参考,不当之处，请联系改正。Edward JennerEradication of smallpox200 yearsafter JennerWHO announcesmallpox eradicated19651970197519

4、80Countries withmore than onesmallpox caseper month30150资料仅供参考,不当之处，请联系改正。4. The concept of “Immunity” developed gradually over time through many scientific findings: = Robert Koch (1905 Nobel Laureate) = Infectious diseases caused by microorganisms= Louis Pasteur = Vaccines against cholera & rabies

5、= These clinical successes = The search of underlying mechanism of “Protection of Infectious Diseases”= The development of “Immunology” Advances in technology (e.g., Cell culture, Monoclonal Ab, Flow cytometry, Genetic engineeringetc) have facilitated our understanding of the immune system and its f

6、unctions. “Descriptive Science” = “Experimental Science”资料仅供参考,不当之处，请联系改正。免疫（免疫（immunity)immunity)传统概念指免除疫病、免除感染，指机体抗感染的防御能力。现代概念指机体对“自己”或“非己”的识别并排除“非己”的功能。资料仅供参考,不当之处，请联系改正。免疫的基本功能免疫的基本功能功能功能正常表现（有利）正常表现（有利）异常表现（有害）异常表现（有害）免疫防御免疫防御immune defenceimmune defence抗病原微生物抗病原微生物的侵袭的侵袭超敏反应超敏反应易受感染或免疫缺陷易受感染或

7、免疫缺陷病病免疫稳定免疫稳定immune homeostasisimmune homeostasis清除损伤、衰老、清除损伤、衰老、死亡细胞死亡细胞 自身免疫性疾病自身免疫性疾病免疫监视免疫监视immune immune surveillancesurveillance清除突变或畸变的清除突变或畸变的恶性细胞恶性细胞 恶性肿瘤恶性肿瘤 资料仅供参考,不当之处，请联系改正。免疫系统免疫系统 (immune system)(immune system)：机体执行免疫功能的组织、器官、细胞和分子构成免疫系统。资料仅供参考,不当之处，请联系改正。The four kinds of pathogens

8、that cause human disease资料仅供参考,不当之处，请联系改正。Overview of immune responses资料仅供参考,不当之处，请联系改正。固有免疫固有免疫（innate immunity）是机体抵御病原微生物入侵的第一道防线，并启动和参与是机体抵御病原微生物入侵的第一道防线，并启动和参与适应性免疫应答。适应性免疫应答。天然免疫（natural immunity)或非特异性免疫(nonspecific immunity)，是个体出生时就具有的免疫力，通过遗传获得，是生物在长期进化过程中逐渐形成的，其针对外来异物的范围广，反应迅速，其应答模式和强度不因与病原微

9、生物的反复接触而改变。固有免疫应答的作用时相：固有免疫应答的作用时相：瞬时固有免疫应答阶段、早期固有免疫应答阶段、适应性免疫应答诱导阶段瞬时固有免疫应答阶段、早期固有免疫应答阶段、适应性免疫应答诱导阶段资料仅供参考,不当之处，请联系改正。固有免疫系统的组成固有免疫系统的组成屏障屏障细胞细胞分子分子皮肤黏膜屏障：皮肤黏膜屏障：物理、化学、微生物物理、化学、微生物血血-脑屏障、血脑屏障、血-胸腺屏障胸腺屏障血血-胎屏障、气胎屏障、气-血屏障血屏障巨噬细胞、中性粒细胞、树突状细胞、巨噬细胞、中性粒细胞、树突状细胞、T 细胞、细胞、NK细胞、细胞、NKT细胞、细胞、B1细胞、肥大细胞、嗜碱性粒细胞细胞

10、、肥大细胞、嗜碱性粒细胞和嗜酸性粒细胞等。和嗜酸性粒细胞等。抗菌肽、溶菌酶、急抗菌肽、溶菌酶、急性期蛋白、补体、细性期蛋白、补体、细胞因子和黏附分子、胞因子和黏附分子、资料仅供参考,不当之处，请联系改正。Epithelial barriers prevent the entry of microbes资料仅供参考,不当之处，请联系改正。固有免疫细胞固有免疫细胞 PhagocyteNKILLs（固有样淋巴细胞）（固有样淋巴细胞）DC MCBasophil Eosinophil T细胞细胞 NKT细胞细胞 B1细胞细胞Monocyte-macrophageNeutrophil资料仅供参考,不当之处

11、，请联系改正。肺部巨噬细胞吞噬大肠杆菌资料仅供参考,不当之处，请联系改正。Phagocytosis by innate immunity资料仅供参考,不当之处，请联系改正。Leukocyte recruitment to sites of inflammationor DC资料仅供参考,不当之处，请联系改正。固有性免疫分子固有性免疫分子指体表分泌液以及血浆和其它体液中能够识别或攻击病原体指体表分泌液以及血浆和其它体液中能够识别或攻击病原体的可溶性分子。的可溶性分子。抗菌肽抗菌肽 antimicrobial peptides溶菌酶溶菌酶 lysozyme急性期蛋白急性期蛋白(acute phas

12、e proteins, APP)脂多糖结合蛋白（脂多糖结合蛋白（LBP）血清淀粉样蛋白（血清淀粉样蛋白（SAP）甘露糖结合蛋白（甘露糖结合蛋白（MBP）C反应蛋白等（反应蛋白等（CRP）补体补体 细胞因子和黏附分子细胞因子和黏附分子资料仅供参考,不当之处，请联系改正。Complement activation pathways 资料仅供参考,不当之处，请联系改正。Elie Mechnikoff:The Pioneer of Innate Immunity1. The Discovery of Phagocytes & Phagocytosis2. The Nobel Laureate in M

13、edicine 1908Adopted from Nature Immunology, July 2008 The development of modern Immunology in 20th century mainly centers on understanding the Adaptive Immune System.资料仅供参考,不当之处，请联系改正。Charles A. Janeway, M.D.Yale Univ. In 1989, Janeway = Immune recognition of microbes = Detection of conserved molecu

14、lar patterns, referred to PAMPs (Pathogen-Associated Molecular Patterns) with features:1. Invariant among a given class of microbes.2. Have essential roles in microbial physiology. 3. Recognized by receptors of the innate immune system, called PRRs (Pattern-Recognition Receptors). 4. Innate immunity

15、 regulates adaptive immunity资料仅供参考,不当之处，请联系改正。 Julie A. Hoffmann, Ph.D.Strasbourg, FranceIn 1996, Hoffmanns group Toll functions as a PRR in Drosophila资料仅供参考,不当之处，请联系改正。Key concepts in innate immunity1. The innate immune system mainly recognizes common structures shared by classes of microbes, = Pat

16、hogen Associated Molecular Patterns (PAMPs), e.g., LPS, Peptidoglycan, Microbial DNA & RNA. 2. Host receptors that recognize PAMPs are called Pattern- Recognition Receptors (PRRs), which are encoded in “Germline” DNA= limited Diversity. 3. Innate immunity not only provide the first line of defenses

17、but link to the program of adaptive immunity.4. PRRs may also recognize components from injured or dead host cells = Autoimmune diseases资料仅供参考,不当之处，请联系改正。Pattern Lipopolysaccharide (LPS) Lipoteichoic acid Bacterial lipopeptides Peptidoglycan Yeast and gram+ bacteria Bacterial DNA (CpG) Flagellin Ter

18、minal mannose/fucose Viral DNA (CpG) ssRNA dsRNAPathogen-AssociatedMolecularPatterns(PAMP)是病原微生物（尤其是原核是病原微生物（尤其是原核生物）表面存在一些人体所生物）表面存在一些人体所没有的，但可为许多相关微没有的，但可为许多相关微生物所共享、结构恒定、进生物所共享、结构恒定、进化保守的分子结构。化保守的分子结构。资料仅供参考,不当之处，请联系改正。损伤相关分子模式损伤相关分子模式（damage-associated molecular patterns，DAMPs）机体自身细胞所释放的内源性分子，即内

19、源性危险信号，来源于受损或坏死组织和某些激活的免疫细胞。主要有HMGB1、热体克蛋白等。资料仅供参考,不当之处，请联系改正。PAMP vs DAMPSterile inflammationconserved microbial motifs VS non-microbial signals 资料仅供参考,不当之处，请联系改正。Toll-like Receptors资料仅供参考,不当之处，请联系改正。Locations of Different PRRsBody fluids-Soluble PRRsCellular PRRs- Cell surface- Endosomes- Cytosol资

20、料仅供参考,不当之处，请联系改正。Surface receptors of macrophagesMac-1、CR3资料仅供参考,不当之处，请联系改正。PRR甘露聚糖凝集素（甘露聚糖凝集素（MBL）C反应蛋白（反应蛋白（CRP）脂多糖结合蛋白（脂多糖结合蛋白（LBP）可溶性：体液和血液可溶性：体液和血液细胞吞噬型：细胞膜细胞吞噬型：细胞膜甘露糖受体（甘露糖受体（MR）清道夫受体（清道夫受体（SR）补体受体（补体受体（CR）Fc受体（受体（FcR）甲酰甲硫氨酰肽受体（甲酰甲硫氨酰肽受体（fMLPR）信号转导型信号转导型细胞膜细胞膜内体、溶酶体内体、溶酶体细胞质细胞质TLR1、2、4、5、6、10

21、、11TLR3、7、8、9NLRs、RLRs、ALRs固有免疫细胞表面、内体、溶酶体、细胞质中、可识别一种或固有免疫细胞表面、内体、溶酶体、细胞质中、可识别一种或多种多种PAMPs或或DAMPs的识别分子。的识别分子。Diversity of pattern recognition receptors资料仅供参考,不当之处，请联系改正。Toll-Like Receptors (TLRs)资料仅供参考,不当之处，请联系改正。MyD88-Dependent and independent Signaling资料仅供参考,不当之处，请联系改正。NLRs are cytoplasmic bacteri

22、al sensors that activate inflammasomes资料仅供参考,不当之处，请联系改正。资料仅供参考,不当之处，请联系改正。1Viral Pattern Recognition Receptors: Signaling and Consequences资料仅供参考,不当之处，请联系改正。Interaction between innate and& adaptive immunity1. Innate immunity = Ag presentation (by Dendritic cells)2. Adaptive immunity = Ag recognition

23、(by T & B lymphocytes)资料仅供参考,不当之处，请联系改正。适应性免疫（adaptive immunity）是机体获得性、抗原特异性、抵抗病原微生物感染是机体获得性、抗原特异性、抵抗病原微生物感染的高效防御机制。的高效防御机制。获得性免疫（获得性免疫（acquired immunity)或特异性或特异性免疫免疫(specific immunity)，是个体出生后，在，是个体出生后，在环境中受抗原刺激所产生的免疫力，针对特定抗原，环境中受抗原刺激所产生的免疫力，针对特定抗原，有特异性、多样性、记忆性和耐受性。有特异性、多样性、记忆性和耐受性。1) 特异性，对某个特定的异物性抗

24、原能引起特异性免疫应答；指抗原特异性。特异性，对某个特定的异物性抗原能引起特异性免疫应答；指抗原特异性。2) 多样性，机体可针对环境中多种多样的抗原，分别建立起不同的特异性免疫多样性，机体可针对环境中多种多样的抗原，分别建立起不同的特异性免疫应答；多样性是特异性产生的基础。应答；多样性是特异性产生的基础。 3) 记忆性，当异物抗原再次入侵时，可产生快而强的再次免疫应答效应；记忆记忆性，当异物抗原再次入侵时，可产生快而强的再次免疫应答效应；记忆性淋巴细胞性淋巴细胞。4) 耐受性，正常情况下，免疫系统对自身成分有保护性的免疫耐受；耐受性，正常情况下，免疫系统对自身成分有保护性的免疫耐受； 资料仅供

25、参考,不当之处，请联系改正。抗原决定簇抗原决定簇Antigenic determinant，AD抗原分子表面具有特殊立体构型和免疫活性的化抗原分子表面具有特殊立体构型和免疫活性的化学基团称为学基团称为抗原决定簇或抗原决定基抗原决定簇或抗原决定基。由于抗由于抗原决定簇通常位于抗原分子表面，因而又称为原决定簇通常位于抗原分子表面，因而又称为抗原表位抗原表位( (epitope) )。 抗原决定簇抗原决定簇抗原决定基抗原决定基 抗原表位抗原表位 抗原决定簇决定抗原的特异性，即决定抗原与抗抗原决定簇决定抗原的特异性，即决定抗原与抗体发生特异性结合的能力体发生特异性结合的能力（实际是抗原（实际是抗原决定

26、簇决定簇与抗体的结合与抗体的结合）。）。ADAD的数目、性质和空间构象决定抗原特异性的数目、性质和空间构象决定抗原特异性抗原以抗原以ADAD与相应抗原受体及抗体特异性结合与相应抗原受体及抗体特异性结合资料仅供参考,不当之处，请联系改正。 T T细胞表位和细胞表位和B B细胞表位细胞表位T T细胞表位细胞表位： TCRTCR识别识别 必须经降解加工处理后才能被必须经降解加工处理后才能被T T细胞识别细胞识别 线性决定簇线性决定簇B B细胞表位细胞表位： BCRBCR识别或抗体识别并结合识别或抗体识别并结合 直接识别直接识别 构象决定簇或线性决定簇构象决定簇或线性决定簇 资料仅供参考,不当之处，请

27、联系改正。抗原提呈细胞(antigen-presenting cell, APC)是指能摄取是指能摄取, 加工处理抗原加工处理抗原, 并将抗原信息提呈给淋并将抗原信息提呈给淋巴细胞的一类免疫细胞，在机体免疫应答过程中发巴细胞的一类免疫细胞，在机体免疫应答过程中发挥重要作用。挥重要作用。此类细胞能辅助和调节此类细胞能辅助和调节T细胞、细胞、B细胞识别抗原并对细胞识别抗原并对其产生应答，故又称为辅佐细胞其产生应答，故又称为辅佐细胞(accessory cell)，简，简称称A细胞。细胞。资料仅供参考,不当之处，请联系改正。APC加工处理的抗原种类加工处理的抗原种类: 外源性抗原外源性抗原(exog

28、enous antigen): 通过吞噬或吞通过吞噬或吞饮等作用被饮等作用被APC从细胞外摄入的抗原，以抗原肽从细胞外摄入的抗原，以抗原肽-MHC I I类分子复合物形式提呈给类分子复合物形式提呈给CD4+T细胞细胞 。 内源性抗原内源性抗原(endogenous antigen): 细胞内合成的细胞内合成的抗原，以抗原肽抗原，以抗原肽-MHC I类分子复合物形式提呈给类分子复合物形式提呈给CD8+T细胞细胞 。 资料仅供参考,不当之处，请联系改正。外源性抗原加工，处理及提呈外源性抗原加工，处理及提呈资料仅供参考,不当之处，请联系改正。内源性抗原加工，处理及提呈内源性抗原加工，处理及提呈内源性

29、抗原经蛋白酶体降解成肽，通过抗原加工相关转运体(TAP1、TAP2)转运进入内质网，与 MHC类分子(在内质网合成)结合成肽-MHCI类复合物，通过高尔基体表达于细胞表面。TAP是内质网上的异源性二聚体，由TAP-1及TAP-2基因编码胞浆中蛋白酶体（proteasomes, 核心成分为低分子量多肽LMP细胞被病毒感染后出现的病毒蛋白，基因突变后产生的肿瘤抗原 资料仅供参考,不当之处，请联系改正。脂类抗原的CD1分子提呈 CD1分子：非经典分子：非经典MHC I类分子，类分子，30%同源性。同源性。提呈抗原：提呈糖脂或脂类抗原，供提呈抗原：提呈糖脂或脂类抗原，供CD1限制性限制性T细胞识别细胞

30、识别CD1分子提呈微生物的分子提呈微生物的脂质抗原，脂质抗原，脂质抗原由脂质抗原由CD1分子提呈后激活分子提呈后激活CD1限制性限制性T细胞。细胞。资料仅供参考,不当之处，请联系改正。Adaptive immunityMain effectors:lAntibodylT cell receptorsBBCRTTCR资料仅供参考,不当之处，请联系改正。THE ADAPTIVE IMMUNE RESPONSEAntibody-Mediated Immunity (AMI)lInvolves B lymphocytes, plasma cells and antibodieslHumoral imm

31、unityName derives from antibodies found in body fluids (humors - old medical term)Cell-Mediated Immunity (CMI)lInvolves T lymphocytes, antigen-presenting cells and MHC (major histocompatibility complex) moleculeslCellular immunity资料仅供参考,不当之处，请联系改正。Types of adaptive immunity1. Humoral immunity = Mole

32、cules in body fluid, e.g. Antibody (Ab) = Key player = B cells = Target extracellular microbes & toxins2. Cell-mediated immunity = Key player = T cells = regulate other immune cells = Target intracellular microbes, e.g. viruses, bacteriaFor innate immunity, it also includes Humoral & Cellular compon

33、ents for immune defense资料仅供参考,不当之处，请联系改正。1 1、抗原提呈与识别阶段（感应阶段）：、抗原提呈与识别阶段（感应阶段）：2 2、活化、增殖、分化阶段（反应阶段）：、活化、增殖、分化阶段（反应阶段）： T T细胞活化、增殖分化为效应细胞活化、增殖分化为效应T T细胞；细胞； B B细胞活化、增殖分化为浆细胞；细胞活化、增殖分化为浆细胞； 部分细胞发育为记忆细胞。部分细胞发育为记忆细胞。3 3、效应阶段：、效应阶段： 效应效应T T细胞对抗原的清除；细胞对抗原的清除； 浆细胞分泌抗体清除抗原。浆细胞分泌抗体清除抗原。免疫应答的三个阶段资料仅供参考,不当之处，请联

34、系改正。Overview of adaptive immune responses资料仅供参考,不当之处，请联系改正。CELL-MEDIATED IMMUNITY (CMI)Directed against intracellular microorganisms lNon-phagocytic cells and phagocytic cellsT-lymphocytes (T cells)lDifferentiate into effector cells following antigen presentation by antigen presenting cells (APCs)Fu

35、nctional types of T cellslHelper (CD4 T cells)TH1 and TH2 cellslCytotoxic (CD8 T cells)资料仅供参考,不当之处，请联系改正。T cells develop in the thymus T cells develop in bone marrow, but in order to mature, they need to migrate to thymus = thymus-(T)-dependent lymphocytes Thymus is a primary lymphoid organ located

36、in the upper thorax (chest), just above the heart. Progenitor (precursor) T cells enter the thymus, where they mature (= produce T cell receptors). Mature T cells leave the thymus and enter the secondary lymphoid tissues, where they become activated after exposure to antigen.T cells develop in bone

37、marrow and then migrate to thymus where they matureMature T cells enter the blood stream, and after infection accumulate in the secondary lymphoid tissues where they are activated. 资料仅供参考,不当之处，请联系改正。T cell development资料仅供参考,不当之处，请联系改正。TSCCD4 RTEDNPre-TCRDPTCRCD4CD8TCRTCRCD8CD4 SPTCRCD4CD4b b-selecti

38、onPositiveselectionNegative selectionFunctional maturationTCR-b b rearrangementTCR-a a rearrangementTCRCD8CD8 SPCD8 RTEDevelopment of ThymocytesDoublenegativeDoublepositiveSinglepositive资料仅供参考,不当之处，请联系改正。Notch Signal and T-lineage Commitment受体受体: Notch 1-4；胸腺细胞表达；胸腺细胞表达Notch1-3；全部效应由；全部效应由Notch 1介导介

39、导 配体：配体：Dll1，3，4， Jagged 1，2；胸腺上皮细胞表达全部配体；胸腺上皮细胞表达全部配体；Dll4 可能为生理性配体可能为生理性配体 T系定向：系定向：始于始于DN1，完成于，完成于DN3；绝对依赖；绝对依赖Notch1信号信号资料仅供参考,不当之处，请联系改正。T cells undergo further differentiation in secondary lymphoid tissues after encounter with antigenOnly a small fraction of naive T cells (mature T cells befor

40、e they encounter antigen) survives the positive and negative selection, and leaves the thymus.Mature naive T cells can re-circulate between blood and lymphoid tissues for many years (in contrast to B cells, which have shorter life span).In secondary lymphoid tissues, T cells accumulate in T cell are

41、as, where they become activated by their specific antigens.Encounter with antigen induces the final stage of T cell development: their differentiation into effector T cells. Some effector T cells stay in the lymphoid tissues (CD4-TH2 cells), while others migrate to site of infection (CD8 and CD4-TH1

42、 cells).资料仅供参考,不当之处，请联系改正。T细胞受体复合物细胞受体复合物由由TCR和和CD3组成。前组成。前者识别和结合抗原肽者识别和结合抗原肽, 后者后者将将TCR获得的抗原信号传递获得的抗原信号传递至细胞内。至细胞内。T细胞对抗原的识别 APCT细胞细胞资料仅供参考,不当之处，请联系改正。 MHC- MHC-B7 CD40 CD58 CD2 资料仅供参考,不当之处，请联系改正。信信 号号第一信号第一信号第二信号第二信号T细胞细胞TCR和和CD4/CD8 CD28APCMHC-肽肽复合物复合物B7(B7.1、B7.2)T细胞活化的双信号刺激细胞活化的双信号刺激 第一信号：TCR对M

43、HCII抗原肽复合物的识别，CD3分子将第一信号传递到细胞内。 第二信号：CD28识别专职APC上的B7分子,又称协同刺激信号。 资料仅供参考,不当之处，请联系改正。资料仅供参考,不当之处，请联系改正。Effector T cells In contrast to terminally differentiated B cells (plasma cells), there are several types of terminally differentiated effector T cells.CD8 T cells Cytotoxic T cells (recognize MHC cl

44、ass I molecules)CD4 T cellsTH1 helper cells (activate macrophages)TH2 helper cells (induce differentiation of B cells into plasma cells and production of antibodies)Activation (cytokines)(recognize MHC II molecules)资料仅供参考,不当之处，请联系改正。资料仅供参考,不当之处，请联系改正。The immune system is maintained in a carefully re

45、gulated balance between the two polarised control arms, Th1 (cellular immunity) and Th2 (humoral immunity).资料仅供参考,不当之处，请联系改正。In disease states the balance is skewed. multiple sclerosis, rheumatoid arthritis and type I diabetes, have a Th1 bias, whereas cancer patients have a Th2 bias. 资料仅供参考,不当之处，请联

46、系改正。资料仅供参考,不当之处，请联系改正。More T helper subsetsTh3: TGF-producing CD4 T cellsTr1: IL-10-producing CD4 T cellsTh9: IL-9-producing CD4 T cellsTfh: follicular helper T cells, located in the follicular regions of lymph nodes and spleen,follicular Th1/Th2/Th17 cells资料仅供参考,不当之处，请联系改正。ANTIBODY-MEDIATED (HUMORA

47、L) IMMUNITYDirected against extracellular microorganisms and toxinsB-lymphocytes (B cells)lDifferentiate into plasma cells which produce antibodieslFunction as antigen-presenting cells (APCs)Classification of Antibodies (Immunoglobulins)lImmunoglobulin M (IgM)lImmunoglobulin G (IgG)lImmunoglobulin A

48、 (IgA)lImmunoglobulin D (IgD)lImmunoglobulin E (IgE)资料仅供参考,不当之处，请联系改正。Paul Ehrlich: One of the fathers of humoral adaptive immunity1. The Discovery of Antibody functions2. The Nobel Laureate in Medicine 1908Adopted from Nature Immunology, July 2008 资料仅供参考,不当之处，请联系改正。 抗体的功能抗体的功能V区的功能区的功能 识别并特异性结合抗原识别

49、并特异性结合抗原 单体（单体（IgG, IgE) 2价价 二聚体二聚体(分泌型分泌型IgA) 4价价 五聚体五聚体(IgM) 10价价 中和效应中和效应 中和毒素和病毒中和毒素和病毒 与与Ag结合结合 促吞噬细胞吞噬促吞噬细胞吞噬资料仅供参考,不当之处，请联系改正。C区的功能区的功能 1.1.激活补体系统激活补体系统 Ab(IgM、IgG) + Ag C1q 补体经典途径补体经典途径 IgG4、IgA和和 IgE的凝聚物的凝聚物 补体旁路途径补体旁路途径 2.2.介导免疫细胞活性介导免疫细胞活性 (1)(1)调理作用（调理作用（opsonization）：IgG + + 抗原抗原( (颗粒性颗

50、粒性) ) FcR（单核、巨噬细胞及中性粒细胞）（单核、巨噬细胞及中性粒细胞） 促促吞噬细胞吞噬；吞噬细胞吞噬； (2)(2)ADCC：IgG + + 抗原抗原( (靶细胞靶细胞) ) Fc R（NK 细细胞）胞） 杀伤杀伤靶细胞；靶细胞； (3)(3)介导超敏反应介导超敏反应：型型、型型和和型超敏反应。型超敏反应。 3.3.穿越胎盘和粘膜穿越胎盘和粘膜资料仅供参考,不当之处，请联系改正。Antibody-Dependent Cellular Cytotoxicity (ADCC) 资料仅供参考,不当之处，请联系改正。Th2与与B细胞的相互作用，获得第二信号：协同刺激信号细胞的相互作用，获得第