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治疗方式方面，老年病人比较倾向于保守治疗，中、青年病人和复发的患者倾向于（微创）手术治疗。
反映出不同患者有着不同的医疗期望。
4.2 两组病人治疗方法、临床疗效、费用及期望值统计（见表3）无论保守治疗还是手术治疗，医生对绝大部分病人（非手术组94.16%；手术组90.51%）都采取了2种以上的治疗方法。
两组病人治疗有效率没有显著性差异（P ＞0.05）。
5 讨论疾病诊疗超市医疗服务模式符合了当前社会医疗需求，满足了患者了解疾病、掌握疾病的心理，改变了过去一切由医生说了算、病人无条件服从的医疗模式。
由于病人及其亲属参与，可以尽量实现患者的医疗期望值。
随着人们生活和工作方式的改变，慢性疼痛已经成为困扰人们工作、生活的一种主要疾病。
疼痛的原因大多与椎间盘及其周围组织病变有关。
中年人（40～50岁组）仍然是腰椎间盘疾病的高发人群，占发病人群的50%以上。
在选择治疗方法方面，老年病患者（60岁以上）趋向于选择非手术治疗（占70.33%），以缓解疼痛为基本需求。
而年轻病患者（40岁以下）在选择非手术和微创手术治疗方法方面没有明显的趋向性（分别为48.75%、51.25%）。
患有2个以上腰椎间盘突出联合病变的病人，更愿意选择微创手术治疗（分别为34.81%、65.19%）。
这可能与多部位联合病变患者临床症状更重、痛苦更大，要求快速解决痛苦的心情更迫切有关，因而选择快速解决疼痛的方法。
医生走出了“见病不见人”思维方式，真正将患者的躯体疾病与其身心因素、社会因素结合到一起。
虽然在理论上，医疗模式已经从过去的单一躯体疾病诊疗模式转变到了现在的“生理-心理-社会”医疗模式，但是，在很多实际医疗状况下，医生更多的只顾及到患者的躯体疾病，较少考虑病人的身心感受和社会因ADCC效应综述赵海琳 何存兰［摘要］ 参与ADCC （antibody dependent cell-mediated cytotoxicity）的效应细胞主要有NK细胞、吞噬细胞、嗜酸性粒细胞等。
ADCC名词解释免疫学ADCC是一种免疫学概念，其全称为抗体依赖性细胞毒性（Antibody Dependent Cell-mediated Cytotoxicity），是一种细胞介导的免疫反应，可用于控制病原体感染和肿瘤生长等。
下面将从定义、机制、作用、影响因素和意义等方面进行解释。
一、定义抗体依赖性细胞毒性是指针对某种抗原形成的抗体与人体天然杀伤细胞或淋巴细胞膜芽B细胞或TH2辅助细胞通过Fc受体结合并利用细胞毒素或酶进行杀伤的一种免疫反应。
二、机制ADCC是通过刺激天然杀伤细胞或淋巴细胞膜芽B细胞或TH2辅助细胞表面的Fc受体（CD16或CD32或CD64等），使其与特异性抗体的Fc 区域结合，从而激活有效的杀伤器官，如胞吞细胞、NK细胞，使它们成为杀伤目标的主要执行工具。
三、作用1、病原体感染：通过抗体与病原体的结合，刺激天然杀伤细胞的Fc 受体，发挥杀伤作用，控制病原体感染。
2、肿瘤治疗：通过抗体与肿瘤特异性抗原的结合，刺激天然杀伤细胞的Fc受体，发挥杀伤作用，控制肿瘤的生长和扩散。
四、影响因素1、抗体亲和力和数量：亲和力和数量越高，ADCC效应越强。
2、细胞毒性：天然杀伤细胞和淋巴细胞等杀伤效果越强，ADCC效应越强。
3、抗体的结构和类别：不同类型的抗体在ADCC中的效果不同，如IgG1和IgG3具有较强的ADCC效应，而IgG2和IgG4效应较弱。
五、意义ADCC是一种重要的免疫反应，可用于控制病原体感染和肿瘤生长等。
研究ADCC对于基础性疾病的治疗、疫苗研究和抗体及药物的开发具有重要意义。
例如，IgG类抗体治疗癌症、艾滋病等，ADCC机制扮演着重要角色。
因此，ADCC的研究及其相关作用机制等方面的深入研究和应用将为疾病预防和治疗提供新思路和方法。
综上所述，ADCC是一种抗体依赖性的细胞毒性，可用于控制病原体感染和肿瘤生长等。
其机制是通过刺激天然杀伤细胞或淋巴细胞膜芽B细胞或TH2辅助细胞表面的Fc受体，使其与特异性抗体的Fc区域结合，从而激活有效的杀伤器官，如胞吞细胞、NK细胞，从而发挥杀伤作用。
免疫学复习习题1．简述适应性免疫应答的特性。
1) 特异性，对某个特定的异物性抗原能引起特异性免疫应答；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应答； 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； 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；5) 自限性，异物抗原激发免疫应答的程度和水平可以自我调控在一定的范围内，以免扩大和累及正常组织。
2、当代免疫学发展的特点是什么？免疫学当前发展是以广度上的“多边缘性”及深度上的“多层次性”作为其主要特点：一、广度的多交叉性现以单一学科发展为多交叉性学科随着分子生物学、细胞生物学及分子遗传学的发展，已形成了分子免疫学、免疫遗传学等当前的前沿分支学科。
在应哟能够基础方面形成了免疫药理学、免疫病理学、免疫生理学、心理神经免疫学、免疫生物学、神经内分泌免疫学等。
二、深度的多层次性上个世纪70年代以来，免疫学已整体水平向细胞及分子水平迅速迈进。
从抗体检测到细胞检测进入到功能应用。
三、发展上的高速度3.抗原的免疫原性强弱是有哪些因素决定的。
影响抗原分子免疫原性的因素：1) 异物性：是指抗原与自身成分相异或未与宿主胚胎期免疫细胞接触过的物质。
抗原与机体之间种系关系越远、组织结构差异越大、免疫原性越强。
同种异体间，于遗传类型不同、组织细胞结构也有差异，也具有免疫原性。
凡胚胎时期未与免疫活性细胞接触过的自身成分也具有免疫原性。
2) 理化状态：①分子量大小：一般分子量大于10KD 免疫原性较强，在一定范围内分子量越大免疫原性越强；②化学性质：一般蛋白质抗原的免疫原性强，核酸和多糖的抗原性弱，脂质一般没有抗原性；③结构的复杂性：苯环氨基酸能增强抗原的免疫原性；④物理状态：一般聚合状态的蛋白质较其单体免疫原性强，颗粒性抗原强于可溶性抗原；④分子构象和易接近性：BCR易接近的抗原决定簇免疫原性强。
3) 机体因素：遗传因素、年龄、性别和健康状态。
变态反应——百度百科2014-4-24 摘编变态反应也叫超敏反应，是指机体对某些抗原初次应答后，再次接受相同抗原刺激时，发生的一种以机体生理功能紊乱或组织细胞损伤为主的特异性免疫应答。
人们日常遇到的皮肤过敏，皮肤骚痒、红肿，就是一种变态反应。
中文名变态反应别称超敏反应应用学科生物适用领域范围医学适用领域范围生态学表现皮肤过敏目录1概述2发生条件3特点和常见病4流行病学5分类▪Ⅰ型变态反应▪Ⅱ型变态反应▪Ⅲ型变态反应▪Ⅳ型变态反应6鉴别▪疥螨▪肠阿米巴病▪隐孢子虫▪分型免疫成分损伤机制寄生虫感染举例1概述若机体已被某种寄生虫抗原致敏，当再次接触相同抗原时则二次免疫应答增强，或长期受染，早期过去后的机体反应相似于二次免疫应答反应。
因免疫应答过强而导致组织损伤（免疫病理变化），即称为变态反应（allergy），或超敏反应（hypersensitivityreaction）。
1963年起Gell与Coombs按变态反应发生发展的近代知识，首先提出四型分型法，即Ⅰ型——速发型（immediat type），Ⅱ型——细胞毒型（cytotoxic type）/细胞溶解型，Ⅲ型——免疫复合物型（immunecomplex type），以上3型均由抗体所介导；而Ⅳ型——迟发型（delayedtype）或细胞介导型（cellmediated type），由[1]所介导。
2发生条件变态反应[2]的发生需要具备两个主要条件：一是容易发生变态反应的特应性体质，这是先天遗传决定的，并可传给下代，其机率遵循遗传法则；二是与抗原的接触，有特应性体质的人与抗原首次接触时即可被致敏，但不产生临床反应，被致敏的机体再次接触同一抗原时，就可发生反应，其时间不定，快者可在再次接触后数秒钟内发生，慢者需数天甚至数月的时间。
3特点和常见病变态反应的是伴有炎症反应和组织损伤。
2005年，在世界首个过敏性疾病日，世界变态反应组织公布对30个国家进行流行病学调查结果显示：在这些国家的12亿总人口中，22%（2亿5 千万人）患有免疫球蛋白E（IgE）介导的过敏性疾病，如过敏性鼻炎、哮喘、结膜炎、湿疹、食物过敏、药物过敏和严重过敏反应等。
微生物adcc的名词解释微生物ADCC（Antibody-dependent cell-mediated cytotoxicity）是一种免疫细胞功能，在人体免疫系统中起着重要的作用。
本文将解释微生物ADCC的意义、机制和相关应用，并举例说明其在不同领域中的应用前景。
ADCC是一种免疫功能，通过特定抗体和免疫细胞的相互作用来杀死被感染的细胞或异常细胞。
微生物ADCC指的是在与微生物感染相关的免疫过程中发生的这种细胞介导的细胞毒性。
ADCC的机制主要通过免疫效应细胞（主要是自然杀伤细胞，NK细胞）与感染细胞之间的相互作用来实现。
在免疫应答中，当微生物（例如病毒、细菌或寄生虫）进入人体后，免疫系统将启动一系列的免疫反应，并产生与这些微生物特异性结合的抗体。
当这些抗体结合在感染细胞表面时，这些免疫效应细胞（如NK细胞）的Fc受体将与抗体结合并激活效应细胞。
这激活会导致细胞释放毒素，例如穿孔素或引起细胞凋亡的酶，最终导致感染细胞死亡。
微生物ADCC在抗体治疗、疫苗研发和免疫监测等方面具有重要的应用价值。
在抗体治疗中，ADCC可以帮助清除体内异常或恶性细胞。
研究发现，通过调节ADCC反应，可以提高抗体治疗的效果。
通过合成与靶向微生物抗原特异性结合的抗体，可以直接提高细胞对微生物的杀伤能力，从而加速感染的清除。
此外，微生物ADCC还在疫苗研发中发挥着重要作用。
通过诱导高水平的ADCC反应，可以增强疫苗的免疫效果。
例如，通过合成抗原特异性的抗体来诱导ADCC反应，可以减少感染细胞的数量，并加速感染部位的清除。
这为病毒和细菌感染的预防提供了新的策略。
对于免疫监测来说，微生物ADCC也是一个重要的指标。
通过测量体内ADCC活性，可以评估免疫功能的健康状态。
这种监测方法可以用来评估人体对不同感染的免疫状况，并指导临床治疗的选择和效果评估。
微生物ADCC的进一步研究和应用将有助于开发新的免疫治疗策略和疫苗设计。
例如，在癌症治疗领域，已经开始探索免疫细胞与肿瘤细胞之间的ADCC相互作用以提高抗体药物的疗效。
adcc 实验方法全文共四篇示例，供读者参考第一篇示例：ADCC（Antibody-Dependent Cellular Cytotoxicity）是一种重要的免疫细胞毒杀机制，它涉及到自然免疫系统中多种免疫细胞的相互作用。
ADCC通常发生在免疫细胞和病原体之间，通过抗体的介导，引起免疫细胞对病原体的杀伤作用。
这种细胞毒杀机制在免疫系统的抗体介导作用中起到重要的作用。
ADCC实验方法是用来研究和评估这种细胞毒杀机制的一种重要工具。
在ADCC实验过程中，研究者会使用抗体来与目标细胞结合，然后通过免疫细胞（通常是自然杀伤细胞）来识别并杀死被抗体标记的目标细胞。
这个实验模型可以帮助研究者了解免疫细胞对抗体标记细胞的杀伤程度，从而评估特定抗体对目标细胞的杀伤效果。
ADCC实验方法通常涉及到以下几个关键步骤：1. 选择合适的抗体和目标细胞：在进行ADCC实验之前，首先需要选择合适的抗体和目标细胞。
抗体可以是单克隆抗体或多克隆抗体，用于与目标细胞特异性结合。
目标细胞通常是肿瘤细胞或感染的细胞，可以选择适当的细胞系用于实验。
2. 准备实验材料：在进行ADCC实验之前，需要准备好所有必要的实验材料，包括细胞培养基、免疫细胞、抗体、目标细胞等。
确保实验材料的纯度和质量符合要求。
3. 进行实验操作：将目标细胞与抗体共培养一段时间，使抗体能够充分与目标细胞结合。
然后将免疫细胞加入混合液中，观察免疫细胞是否能够识别并杀伤目标细胞。
可以根据实验设计选择适当的细胞毒杀指标，如细胞溶解率或细胞凋亡率等来评估实验结果。
4. 数据分析和结果解释：进行实验后，需要对实验数据进行统计分析和结果解释。
通过比较不同实验条件下的细胞毒杀效果，可以评估特定抗体对目标细胞的ADCC效果，并验证抗体的免疫治疗潜力。
ADCC实验方法是一种重要的免疫学实验技术，可用于评估抗体介导的细胞毒杀效应，深入了解免疫细胞对目标细胞的杀伤机制，为研究新型抗体药物及免疫治疗方法提供重要参考依据。
免疫学部分一、概述【A型题】1.免疫的概念是：A.机体的抗微生物感染功能B.机体清除损伤和衰老细胞的功能C.机体排除非自身物质的功能D.机体识别、杀灭与清除外来微生物的功能E.机体识别和排除抗原性物质的功能2.免疫监视功能低下的后果是A.易发生肿瘤B.易发生超敏反应C.易发生感染D.易发生自身免疫病E.易发生免耐受3.免疫应答对机体是：A.有利的反应B.不利的反应C.有时有利，有时不利D.适当时有利，不适当时不利E.以上都不是【X型题】1.免疫功能在正常情况下可表现为A.阻止病原微生物入侵B.对自身组织成分的耐受C.清除体内损伤、衰老细胞D.诱导组织细胞突变E.防止肿瘤发生二、抗原【A型题】1.一般而言，抗原的分子量为多少才具有免疫原性A.<10kDB.< 9kDC.=10kDD.>10kDE.>100kD2.引起同胞兄弟之间移植排斥反应的抗原属于A.异种抗原B.同种异型抗原C.自身抗原D.异嗜性抗原E.感染的微生物抗原－Ag得名，是因为它A.在胸腺中产生B.相应抗体在胸腺中产生C.对此抗原不产生体液免疫D.只引起迟发型变态反应E.相应的抗体产生需T细胞辅助4.决定抗原特异性的物质基础是A.抗原决定基B.抗原的大小C.抗原的电荷性质D.载体的性质E.抗原的物理性状5.下列哪种物质没有免疫原性A.异嗜性抗原B.抗体C.补体D.半抗原E.细菌多糖6.异嗜性抗原广泛存在于：A.人与人之间B.动物与动物之间C.植物与植物之间D.微生物与微生物之间E.不同种属之间7.自身抗原刺激机体产生免疫应答提示：A.自身耐受的终止B.机体易受微生物感染C.免疫监视功能被抑制D.免疫应答被抑制E.抗原的免疫原性增强8.接种牛痘疫苗后机体产生了对天花病毒的免疫力，反映了这两种抗原分子的A.特异性B.交叉反应性C.分子量大D.异种性E.化学结构复杂是人类的A.同种异型抗原B.异嗜性抗原C.自身抗原D.肿瘤抗原E.佐剂10.有关半抗原，下列叙述正确的是A.通常是蛋白质和多糖等大分子B.本身没有免疫原性C.只能诱导体液免疫D.与载体结合后才能与抗体结合E.具有多个表位11.抗原特异性取决于抗原分子的A.物理性状B.分子量大小C.异物性D.结构的复杂性E.表面的特殊化学基团12.同一种属不同个体之间所存在的抗原称A.异种抗原B.同种异体抗原C.自身抗原D.异嗜性抗原E.独特型抗原【X型题】1.使自身成分变为自身抗原的因素可能有A.大面积烧伤B.大面积冻伤C.电离辐射D.药物E.感染2.隐蔽抗原包括A.脑组织B.眼晶状体蛋白C.甲状腺球蛋白D.精子E.干细胞3.关于半抗原的叙述，下列哪项是正确的A.既有免疫原性又有抗原性B.只具有免疫原性而无抗原性C.只具有抗原性而无免疫原性D.与蛋白质载体结合后就具有免疫原性E.与蛋白质载体结合后就具有抗原性三、抗体【A型题】1.抗体与抗原结合的部位是(可变区)和VL2.下列备选答案中，哪个是错误的A.分子量最大的是IgMB.血清含量最高的是lgM (是IgG)C.个体发育中产生最早的是IgMD.血清中含量最低的Ig是IgEE.与抗原结合后激活补体能力最强的Ig是IgM3.能与肥大细胞表面 FcR结合，并介导1型超敏反应的 Ig是4.下面哪一类Ig参与粘膜局部抗感染5.免疫接种后首先产生的抗体是6.新生儿从母乳中获得的Ig是类抗体类抗体类抗体类抗体类抗体7.产生抗体的细胞是细胞细胞 C.浆细胞细胞 E.肥大细胞分子的基本结构是A.由2条重链和2条轻链组成的四肽链结构B.由1条重链和1条轻键组成的二肽链结构C.由2条相同的重链和2条相同的轻链组成的四肽链结构D.由1条重链和2条轻链组成的三肽键结构E.由4条相同的肽链组成的四肽链结构9.人类血清中含量最高、半衰期最长的Ig类别是。
医学adcc的名词解释ADCC（Antibody-dependent cell-mediated cytotoxicity）是一种特殊的免疫反应过程，指在抗体的介导下，由免疫细胞执行的细胞毒杀作用。
该过程在医学领域中被广泛应用于治疗肿瘤和传染病等疾病。
ADCC的基本机制是通过抗体与目标细胞（如肿瘤细胞或感染的细菌）结合，使得免疫细胞（如自然杀伤细胞或巨噬细胞）得以识别并对目标细胞进行杀伤。
ADCC的作用机理涉及多种免疫细胞表面的受体和结合蛋白，以及抗体与受体之间的相互作用。
这些相互作用激活了免疫细胞内的细胞毒杀机制，包括释放细胞毒素、溶酶体的释放和调控性分子的释放等。
ADCC的应用非常广泛，其中最重要的应用之一就是在肿瘤免疫治疗领域。
通过选择性激活免疫细胞对癌细胞进行攻击，ADCC可以在不伤害正常细胞的情况下，精准地杀灭癌细胞。
这种治疗策略可通过靶向性抗体来实现。
抗体可以与癌细胞上过表达的抗原结合，从而引导和激活免疫细胞进行细胞毒杀。
临床上，ADCC已被证明对肿瘤治疗具有很高的潜力，包括对乳腺癌、恶性淋巴瘤和结直肠癌等多种癌症的治疗。
此外，ADCC还可以用于治疗传染病。
一些病原体表面表达的抗原可以作为靶点，由抗体激活免疫细胞执行ADCC杀伤病原体。
这种治疗策略在病毒性感染、细菌感染和寄生虫感染等领域已被研究和应用。
一种常见的ADCC治疗方法是将靶向性抗体与细胞毒素连接起来，形成所谓的免疫毒素。
这种免疫毒素能够同时利用抗体碰撞受体激活免疫细胞，并通过免疫细胞释放细胞毒素杀灭目标细胞。
现代生物技术的发展使得研发和生产这种免疫毒素变得更加有效和可行，为临床应用提供了坚实的基础。
虽然ADCC有着广泛的应用前景，但也面临一些挑战。
首先，ADCC的效果在不同个体间可能会有差异，这与免疫细胞活性和患者体内抗体水平等因素有关。
其次，某些疾病类型可能没有足够的靶点供抗体选择。
此外，抗体疗法还可能面临抗体耐药性和免疫耐受性等问题。
REVIEW ARTICLEpublished:27March2013doi:10.3389/fimmu.2013.00076 Natural killer cell mediated antibody-dependent cellular cytotoxicity in tumor immunotherapy with therapeutic antibodiesUrsula J.E.Seidel,Patrick Schlegel and Peter Lang*Department of General Paediatrics,Oncology/Haematology,University Children’s Hospital Tübingen,Tübingen,GermanyEdited by:Hermann Einsele,University Hospital Würzburg,GermanyReviewed by:Rupali Das,Children’s Hospital of Philadelphia,USAStanislaw Stepkowski,University of Toledo College of Medicine,USA*Correspondence:Peter Lang,Department of General Paediatrics,Oncology/Haematology, University Children’s HospitalTübingen,Hoppe-Seyler-Str.1,72076 Tübingen,Germany.e-mail:ng@med.uni-tuebingen.de In the last decade several therapeutic antibodies have been Federal Drug Administration (FDA)and European Medicines Agency(EMEA)approved.Although their mechanisms of action in vivo is not fully elucidated,antibody-dependent cellular cytotoxicity(ADCC)medi-ated by natural killer(NK)cells is presumed to be a key effector function.A substantial role of ADCC has been demonstrated in vitro and in mouse tumor models.However,a direct in vivo effect of ADCC in tumor reactivity in humans remains to be shown.Several studies revealed a predictive value of FcγRIIIa-V158F polymorphism in monoclonal anti-body treatment,indicating a potential effect of ADCC on outcome for certain indications. Furthermore,the use of therapeutic antibodies after allogeneic hematopoietic stem cell transplantation is an interesting option.Studying the role of the FcγRIIIa-V158F polymor-phism and the influence of Killer-cell Immunoglobuline-like Receptor(KIR)receptor ligand incompatibility on ADCC in this approach may contribute to future transplantation strate-gies.Despite the success of approved second-generation antibodies in the treatment of several malignancies,efforts are made to further augment ADCC in vivo by antibody engi-neering.Here,we review currently used therapeutic antibodies for which ADCC has been suggested as effector function.Keywords:natural killer cells,ADCC,tumor immunotherapy,therapeutic antibodies,allogeneic stem cell transplan-tationINTRODUCTIONNaturally cytotoxic cells against tumor cells werefirst described in humans and mice in the1970s of the last century(Rosenberg et al., 1972;Oldham and Herberman,1973;Herberman et al.,1975a,b; Kiessling et al.,1975a,b).Initially regarded as artifacts,these cells were recognized eventually as a novel lymphocyte population and named natural killer(NK)cells after their natural occurrence and spontaneous capacity to kill lymphomas and leukemic cells in non-immunized animals(Kiessling et al.,1975a,b).Nowadays,NK cells are recognized as a subset of cytotoxic innate lymphoid cells(ILCs) which are able to directly kill virus-infected cells and tumor cells and participate in shaping the adaptive immunity by secretion of cytokines(e.g.,IFN-γ)(Vivier et al.,2011).The role of NK cells in human cancer is highlighted by a study linking low peripheral blood NK cell activity with increased cancer risk(Imai et al.,2000). Furthermore,an association of NK cell infiltration into the tumor site with better disease prognosis has been shown for several malig-nancies(Carrega et al.,2008;Halama et al.,2011;Platonova et al., 2011;Eckl et al.,2012).Human NK cells are defined by the phenotype CD3−CD56+; additionally they are CD19and CD14negative.The only marker that is specific for NK cells is NKp46.NK cells comprise5–15% of all circulating lymphocytes(Lanier et al.,1986;Walzer et al., 2007).They are commonly divided into two major subpopula-tions,CD56dim CD16+and CD56bright CD16−,with each of those possessing distinct effector functions.The CD56dim CD16+subset comprises90%of all peripheral blood NK cells and mediates an early response via direct cellular cytotoxicity induced by perforin and granzyme,FasL,and TRAIL interactions as well as cytokine production(De Maria et al.,2011).One major characteristic of NK cells is their constant state of readiness to respond immedi-ately.In contrast to T cells,NK cells constitutively express perforin. This facilitates the instant polarized delivery of apoptosis-inducing granzymes after formation of a lytic synapse between the NK cell and a target cell(Shresta et al.,1995).The CD56bright CD16−subset mediates a late but sustained effector function via potent pro-inflammatory cytokine and chemokine release of mainly IFN-γ,but is poorly cytotoxic(De Maria et al.,2011).NK cell activation and cytotoxicity is controlled by a complex balance between acti-vating receptors,inhibitory receptors and co-receptors(Lanier, 2003;Leung,2011).Positive and negative downstream signals of these receptors are integrated and decisive for NK cell activa-tion(Figure1).Hence,absence of inhibitory signals on target cells together with engagement of activating receptors as NKG2D, DNAM-1,and2B4as well as the natural cytotoxicity receptors (NCRs),including NKp46,NKp44,and NKp30mediate triggering of resting NK cells(Moretta et al.,2001;Bryceson and Long,2008; Lanier,2008).Whereas for NKG2D,DNAM-1,and2B4multiple ligands are known(Bottino et al.,2005),despite their involvement in tumor cell lysis the NCR ligands have remained rather elusive (Moretta et al.,2006).Nevertheless,NKp30has been shown to recognize a tumor cell ligand of the B7family,B7-H6(Brandt et al.,2009)and NKp44is suggested to recognize proliferating cell nuclear antigen(PCNA),which surprisingly triggers inhibition ofFIGURE1|Antibody-dependent cellular cytotoxicity in therapeutic antibody treatment.(A)Without antibody therapy,NK cells are tolerant to healthy cells and tumor cells,if the strength of activating signal they receive upon encountering activating ligands on these malignant cells does not overcome the inhibitory signaling delivered by inhibitory ligands as,e.g.,MHC class I molecules.(B)Upon treatment with tumor antigen-associated(TAA) specifc antibody,the activating stimulus from FcγRIIIa induced by antibodies cross-linking NK cells with TAA-expressing healthy and malignant cells overcomes inhibitory signals.This leads to the activation of NK cells and ADCC is mediated by releasing cytotoxic granules containing perforin and granzyme.NK cells(Rosental et al.,2011).However,several of those receptors need to be triggered by target cells for activating downstream sig-nals to prevail over inhibitory signals and NK cells to be activated and to mediate target cell lysis(Moretta et al.,2001;Bryceson et al., 2006).ANTIBODY-DEPENDENT CELLULAR CYTOTOXICITYMost hematopoietic cells,except most T cell subsets,express Fcγreceptors(FcγRs)(Nimmerjahn and Ravetch,2008).There are three types of FcγRs which recognize the Fc part of IgG antibody subclasses with different affinities.The activating FcγRI(CD64) binds to human IgG1and IgG3with high affinity,is expressed on macrophages and neutrophils,and mediates phagocytosis of target cells.The FcγRII(CD32)class comprises activating low affinity FcγRIIa(which binds human IgG1,IgG2,and IgG3)and inhibitory FcγRIIb(which recognizes human IgG1and IgG3with low affinity)and may attenuate signaling from activating receptors as FcγRI if engaged in phagocytes.FcγRIIIb is a protein expressed by neutrophils and may play a role in neutrophil activation.Acti-vating low affinity FcγRIIIa(type III receptor for IgG;CD16) mediates antibody-dependent cellular cytotoxicity(ADCC)and is highly expressed on the cytotoxic CD56dim CD16+NK cell subset as well as on other hematopoietic cells.Nevertheless,NK cells are thought to be the key mediators of ADCC,since only NK cells do not co-express the inhibitory FcγRIIb.In contrast, all other FcγR-expressing cells are tightly controlled by the bal-ance between activating and inhibitory FcγRs.Efficient FcγRIIIa signaling depends on high avidity for specific binding to anti-bodies which ensures that NK cells are activated when antibodies have bound to a multimeric or multivalent cognate antigen only (Banks et al.,2002).These antibodies of the subclasses IgG1and IgG3binding to FcγRIIIa induce a potent activating signal which overcomes inhibitory signals and results in both cytotoxicity and a cytokine response(Chan et al.,2012)(Figure1).Co-engagement of other activating receptors has a synergistic effect and may enhance NK cell activation(Bryceson et al.,2006).Several mouse model studies postulated the impact of activat-ing FcγRs on anti-tumor effects in antibody therapy indicating that ADCC has a substantial effect on tumor rejection.A study using a xenograft breast carcinoma model has shown that an antibody engineered to prevent Fc binding to FcγRIIIa and spe-cific to Her2/neu[Human Epidermal Growth Factor Receptor (EGFR)2,CD340]which is overexpressed in certain aggressive types of breast cancer,was,in contrary to its murine parental anti-body targeting Her2/neu,unable to arrest tumor growth in vivo (Clynes et al.,2000).Additionally,this study in mice showed in a murine lymphoma model that treatment with CD20-specific anti-body rituximab was capable of preventing tumor growth in FcR wild-type mice whereas FcR knock-out mice failed to mediate antibody-dependent tumor protection.Another study demon-strated ADCC in mice in vivo by showing formation of ADCC synapses in immunocompetent mice bearing a murine breast tumor treated with an antibody specific to Tn,a glycopeptidic antigen which is expressed by breast cancer and a variety of other epithelial tumors in mice and humans(Hubert et al.,2011). Additionally,tumor rejection was abolished in mice deficient for FcγRs–emphasizing the potential role of ADCC(Hubert et al., 2011).Another study investigated the relative contributions of complement-dependent cytotoxicity(CDC)and ADCC in a murine GD2-expressing metastatic lymphoma model treated with an antibody specific to the disialoganglioside GD2utilizing wild-type,complement-deficient,complement-receptor-deficient,and FcγRI/III-deficient mice.Outcome after treatment with the ADCC and CDC mediating GD2antibody was unaffected in mice inca-pable for CDC but was almost completely abrogated in FcγRI/III-deficient mice that were disqualified for ADCC(Imai et al.,2005). These results further highlight the key role of ADCC in anti-tumor effects in mice in vivo.In men it has been shown,that breast can-cer patients who responded with partial or complete remission to Her2/neu-specific antibody trastuzumab have a higher capacity to mediate ADCC in vitro than patients which failed to respond to antibody therapy(Musolino et al.,2008).These studies indicate that,at least in murine models,ADCC is a considerable component of the in vivo activity of therapeu-tic antibodies against tumors.However,studies with therapeutic antibodies in humans which demonstrate the direct influence of ADCC,as,e.g.,ADCC as the single effector mechanism,remain to be conducted.Therefore,the direct in vivo effect of ADCC in tumor reactivity in humans remains to be shown. INFLUENCE OF FcγRIIIa POLYMORPHISM AND KILLER-CELL IMMUNOGLOBULINE-LIKE RECEPTOR(KIR)RECEPTOR LIGAND INCOMPATIBILITY ON ADCC IN PATIENTSIn the past15years,12therapeutic antibodies have reached FDA approval for hematological malignancies as well as solid tumors (Scott et al.,2012).Their mechanisms of action include direct anti-tumor effects as induction of apoptosis,blocking receptor signaling or acting as an agonist,delivery of a cytotoxic agent, immune-mediated effects as CDC and ADCC as well as effects on the tumor microenvironment.At leastfive of these antibod-ies mediate efficient ADCC and a large number of new con-structs are currently under investigation in early and late phase clinical trials(Table1).In this review we will use anti-CD20-specific monoclonal antibody(mAb)rituximab,CD52-specific mAb alemtuzumab,Her2/neu-specific mAb trastuzumab,EGFR-specific mAb cetuximab,and anti-GD2antibodies to discuss the influence of ADCC in treatment with therapeutic antibodies.The CD16encoding gene FCGR3A bears a single nucleotide polymorphism(SNP)at nucleotide526[thymidine (T)→guanine(G)]resulting in an amino acid(aa)exchange at aa position158of phenylalanine(F)to valine(V).It has been demonstrated that human IgG1binds more efficiently to NK cells expressing the FcγRIIIa-158V allotype than to the FcγRIIIa-158F allotype(Koene et al.,1997;Wu et al.,1997).In vitro studies have shown that the increased binding is caused by a significantly higher affinity of IgG antibodies to FcγRIIIa-158V receptors,whereas expression levels of FcγRIIIa on NK cells are not influenced by the FcγRIIIa polymorphism(Dall’Ozzo et al.,2004;Congy-Jolivet et al.,2008).Furthermore,the adequate rituximab concentration exciting50%lysis of a CD20+tumor cell line has been shown to be significantly lower in FcγRIIIa-158V/V donors compared to FcγRIIIa-158F/F donors(Dall’Ozzo et al.,2004).Several clinical studies investigating antibodies which utilize an ADCC-mediating therapeutic antibody suggest that patients with the FcγRIIIa-158V allotype have a better clinical outcome. However,conflicting data have been published.First,we will dis-cuss the chimeric IgG1CD20-specific antibody rituximab which is approved for treatment of CD20+B-cell non-Hodgkin’s lym-phoma(NHL),CD20+follicular NHL,and chronic lymphocytic leukemia(CLL).Rituximab is the most extensively studied anti-body mediating ADCC as its key effector mechanism(Cheson and Leonard,2008;Alduaij and Illidge,2011).Thefirst study by Cartron et al.(2002)suggested that the homozygous FcγRIIIa-158V/V genotype is beneficial in patients with follicular NHL regarding clinical and molecular responses to single agent ritux-imab.These results were confirmed in a larger follicular lymphoma patient cohort treated with rituximab as monotherapy and an association of the FcγRIIIa-158V/V genotype with progression-free survival could be shown(Weng and Levy,2003).Another study analyzing the effect of the FcγRIIIa genotype on the outcome of patients to single agent rituximab promoted some of the above mentioned reports by suggesting a significant improvement in event-free survival in FcγRIIIa-158V/V patients(Ghielmini et al., 2005).Furthermore,it has been postulated that NK cells from lymphoma patients with the FcγRIIIa-158V allotype but not from patients that are homozygous for FcγRIIIa-158F/F were activated after rituximab application(Veeramani et al.,2011).On the contrary,no influence of the FcγRIIIa-F158V polymor-phism on the outcome of follicular lymphoma patients treated with risk-adapted chemotherapy and rituximab has been shown (Prochazka et al.,2011).Similarly,in relapsed or refractory CLLT able1|ADCC-mediating therapeutic antibodies currently FDA approved for cancer therapy.Antibody Antigen Cancer indication Mechanisms of actionRituximab CD20CD20+B cell NHL,CD20+follicular NHL,CLL ADCC,CDC,direct induction of apoptosis Ofatumumab CD20CLL ADCC,CDCTrastuzumab Her2/neu Breast cancer ADCC,abrogation of tumor cell signaling Cetuximab EGFR colorectal cancer,SCCHN ADCC,abrogation of tumor cell signaling Alemtuzumab*CD52CLL ADCC,CDC,direct induction of apoptosisNHL,non-Hodgkin’s lymphoma;CLL,chronic lymphocytic leukemia;ADCC,antibody-dependent cellular cytotoxicity;CDC,complement-dependent cytotoxicity; SCCHN,squamous cell carcinoma of the head and neck.*Withdrawn from the market in August,2012.patients treated with chemotherapy and rituximab,no significant influence of the FcγRIIIa-F158V polymorphism was demon-strated(Dornan et al.,2010).Another study evaluated the impact of the FcγRIIIa-F158V polymorphism on the response to rit-uximab in combination with a chemotherapy regimen(ritux-imab with cyclophosphamide,hydroxydaunorubicin,oncovin, and predniso(lo)ne,R-CHOP)in diffuse large B cell lymphoma (DLBCL)patients.The FcγRIIIa-158V allotype was shown to be significantly correlated with a higher complete response rate com-pared with the FcγRIIIa-158F allotype(Kim et al.,2006).However, overall survival did not correlate with the FcγRIIIa-158V/V geno-type and several other studies investigating the impact of the FcγRIIIa-F158V polymorphism in DLBCL found no association with the response to R-CHOP(Carlotti et al.,2007;Mitrovic et al., 2007;Varoczy et al.,2012).Interestingly,all studies conducted with rituximab as monotherapy show an impact of the FcγRIIIa-F158V polymorphism and therefore indicate an important influence of ADCC on clinical outcome.However,the picture is less clear when rituximab is combined with chemotherapy.Since combined chemotherapy may hamper ADCC due to impaired NK cell func-tion the combination of rituximab with chemotherapy might mask the influence of the FcγRIIIa genotype and ADCC.Nevertheless,a combination of rituximab with chemotherapy generally improves clinical results.The humanized IgG1mAb alemtuzumab was approved for treatment of B-CLL and is directed against the glycoprotein CD52 (Hillmen et al.,2007).The therapeutic antibody was withdrawn from the market in2012in order to optimize the pending launch of the agent as a treatment for multiple sclerosis.The predomi-nant mechanism of action of alemtuzumab in vivo has not been clearly defined but involvement of ADCC mediated by NK cells and neutrophils has been suggested by studies employing a human CD52transgenic mouse model and a xenograft model(Hu et al., 2009;Siders et al.,2010).In addition,CDC and direct induction of apoptosis have been identified as other potential mechanisms of action in in vitro studies(Table1)(Crowe et al.,1992;Mone et al.,2006).A study exploiting the predictive value of FcγRIIIa polymorphism in a small CLL patient cohort(n=33)treated with alemtuzumab found no association of responsiveness to the mAb with a FcγRIIIa-F158V allotype(Lin et al.,2005).However,further studies with larger patient cohorts are required in order to deter-mine the potential influence of FcγRIIIa-F158V polymorphism and ADCC in treatment with alemtuzumab.The humanized IgG1mAb trastuzumab is applicable in HER2/neu-positive breast cancer patients and mediates abroga-tion of tumor cell signaling and ADCC(Table1)(Hudis,2007).A study investigating breast cancer patients treated with trastuzumab and a chemotherapeutic agent postulated a higher response rate and longer progression-free survival in homozygous FcγRIIIa-158V/V patients compared to patients with the FcγRIIIa-158F allotype(Musolino et al.,2008).In contrast,another study sug-gested a correlation of the FcγRIIa-131H/H genotype with objec-tive response and progression-free survival in HER2/neu-positive non-metastatic and metastatic breast cancer patients treated with chemotherapy and trastuzumab but no significant correlation was observed for the FcγRIIIa-F158V/V genotype(Tamura et al., 2011).Furthermore,another recent study postulated a lack of correlation between FcγRIIIa genotypes and trastuzumab efficacy in HER2/neu-positive non-metastatic breast cancer patients treated with a combined trastuzumab-chemotherapy(Hurvitz et al.,2012).Since no studies with trastuzumab as single agent have been published and besides ADCC abrogation of tumor cell signaling being a major effector mechanism of trastuzumab the influence of FcγRIIIa-F158V polymorphism and ADCC on clinical outcome is hard to substantiate.The chimeric IgG1therapeutic antibody cetuximab targets EGFR in colorectal cancer(CRC)and has like trastuzumab ADCC and abrogation of tumor cell signaling as the modes of action (Table1)(Van Cutsem et al.,2009).A study suggested a signifi-cantly higher clinical benefit after treatment with cetuximab and chemotherapy in homozygous FcγRIIIa-158V/V and or FcγRIIa-131H/H patients.These results were independent from the GTPase KRas(KRAS)mutation status in metastatic CRC(mCRC)(Bibeau et al.,2009).Furthermore,a higher disease control rate in KRAS-mutated mCRC patients harboring the FcγRIIa-131H/H genotype and treated with combined cetuximab-chemotherapy has been shown(Rodriguez et al.,2012).It has been suggested that the pre-dictive value of FcγRIIa-H131R polymorphism may result from linkage disequilibrium between FcγRIIIa-V158F and FcγRIIa-H131R and therefore nevertheless indicates an effect of ADCC (Lejeune et al.,2008).Similarly,the association of the FcγRIIIa-F158V polymorphism with progression-free survival has been sug-gested for single agent cetuximab treated mCRC patients(Zhang et al.,2007).However,in this study and in another study from Dahan et al.investigating combined cetuximab-chemotherapy treatment,the FcγRIIIa-158F allele rather than the FcγRIIIa-158V allele had a favorable influence on overall and progression-free sur-vival(Zhang et al.,2007;Dahan et al.,2011).Beyond that,a recent study found no association of clinical outcome in a patient cohort of107mCRC patients treated with cetuximab and chemother-apy and FcγRIIIa-F158V and FcγRIIa-H131R polymorphisms (Park et al.,2012).These discrepancies related to the predictive value of the FcγRIIIa-F158V polymorphism on cetuximab treat-ment are difficult to explain and indicate a demand for further elaborated investigations in larger patient cohorts.Interestingly, mutated KRAS induces a ligand-independent activation of EGFR downstream signaling pathways.Hence,the key effector mecha-nism of cetuximab besides ADCC,namely abrogation of tumor signaling,is invalidated by KRAS mutations.Clinical benefit of cetuximab yet seen in these patients and the predictive value of FcγRIIIa-V158F genotype emphasizes the impact of ADCC.Disialoganglioside GD2is a sialic acid containing glycosphin-golipid which is uniformly expressed in neuroblastoma and most melanomas but also to a variable degree in some other tumors (Navid et al.,2010).Due to its tumor-associated expression,several anti-GD2antibodies such as the chimeric IgG1antibody ch14.18 and its humanized counterpart hu14.18as well as3F8have been developed and deployed in the clinic.The mechanisms of actions of these antibodies are ADCC and CDC.Several years ago,a phase I study with pediatric neuroblastoma patients treated with anti-GD2antibody ch14.18was conducted at our institute and elicited some complete and partial tumor responses in neuroblastoma patients(Handgretinger et al.,1995).Currently,we are conducting an ongoing phase I/II-trial for relapsed metastatic neuroblastomawith subsequent immunotherapy with ch14.18/Chinese hamster ovary(CHO)after HLA mismatched,haploidentical stem cell transplantation(SCT)at our institution.Preliminary results show effective ADCC and complement-mediated anti-tumor effects against neuroblastoma cells with donor-derived NK cells in vitro as well as significant anti-tumor effects in vivo(unpublished data). Due to yet small patient cohorts,the role of FcγRIIIa-F158V poly-morphism in treatment with GD2antibodies has not been studied up to now.However,there are a variety of further studies ongoing which investigate the in vivo efficacy of GD2antibodies(Navid et al.,2010;Shusterman et al.,2010;Yu et al.,2010;Alderson and Sondel,2011;Simon et al.,2011).Yu et al.demonstrated in a ran-domized trial a significantly better event-free survival for patients who received a combination of ch14.18,GM-CSF,and interleukin 2than patients without ch14.18.Additionally,the third-generation antibody hu14.18K322A,which bears an aa substitution in the CH2part,has been suggested to induce increased dose-dependent ADCC compared to ch14.18and hu14.18,whereas dose-limiting CDC is intercepted by the Fc modification(Navid et al.,2010). In fact,results from studies conducted with this antibody in vivo will be interesting regarding anti-tumor effects caused by ADCC as single mode of action without involvement of any other effector mechanisms.In adult acute myeloid leukemia(AML)and pediatric acute lymphoblastic leukemia(ALL)donor versus recipient NK cell alloreactivity is a key mechanism after HLA mismatched,hap-loidentical SCT,and has been reviewed elsewhere(Velardi et al., 2012).These“unlicensed”NK cells are characterized in the autol-ogous setting by lacking self-KIRs and are thought to be beneficial in patients with neuroblastoma as well(Venstrom et al.,2009; Delgado et al.,2010).Interestingly,a recent study investigating the differential potential for ADCC of“licensed”and“unlicensed”NK cells in neuroblastoma,showed that“unlicensed”NK cells mediate ADCC most effectively against neuroblastoma cell lines under inflammatory conditions(Tarek et al.,2012).Based on these studies and our ongoing trial with HLA mismatched,haploiden-tical stem cell transplanted neuroblastoma patients treated with ch14.18/CHO we suggest that in the allogeneic,HLA mismatched SCT setting,KIR receptor ligand incompatibility may have syn-ergistic effects with subsequent antibody therapy and propose further exploration of this hypothesis in larger clinical trials. ENHANCED ADCC BY THIRD-GENERATION MONOCLONAL ANTIBODIESPresuming that ADCC is a key mediator of anti-tumor effects in vivo,enhancing ADCC by engineering mAbs is expected to markedly improve clinical efficacy of therapeutic antibodies.Two main approaches of optimizing FcγRIIIa binding by enhancing the affinity of mAbs have been suggested and shown to induce 5-to100-fold increased ADCC in vitro in recent years:molecular modifications in the Fc portion leading to aa substitutions(Shields et al.,2001;Lazar et al.,2006;Stavenhagen et al.,2007)and mod-ifying Fc-linked glycosylation(Umana et al.,1999;Davies et al., 2001;Shinkawa et al.,2003).The approach of optimizing the Fc portion of a therapeutic antibody via aa substitutions predominantly intends to enhance ADCC by increasing the affinity to activating FcγRIIIa and reducing the affinity to inhibitory FcγRIIb.A considerable number of these third-generation monoclonal antibodies are currently under early clinical investigation.These therapeutic antibodies target among others CD19,CD20,CD30,CD40,and FLT3in hematological malignancies and all of them aim at achieving highly augmented ADCC in vivo(Awan et al.,2010;Foyil and Bartlett,2010;Horton et al.,2010;Le Garff-Tavernier et al.,2011; Hofmann et al.,2012;Kellner et al.,2013).Furthermore,a CD19-specific Fc-optimized therapeutic antibody is currently evaluated in pediatric patients with refractory acute B-lineage leukemia after allogeneic SCT within the scope of a compassionate use program at our institution.In four out of six patients at very high risk of relapse,minimal residual disease could be significantly reduced or completely eradicated with a longest follow up of15months (unpublished data).Other attempts aim at reduction of CDC related toxicity as applied in GD2targeting hu14.18K322A in neu-roblastoma(Lazar et al.,2006;Sorkin et al.,2010)or enhancing affinity to low affinity allele FcγRIIIa-158F(Bowles et al.,2006; Nordstrom et al.,2011).Recently,a phase I trial investigating a Fc-engineered antibody targeting CD20in follicular lymphoma patients has suggested encouraging results even in patients with the less favorable FcγRIIIa-F allotype(Forero-Torres et al.,2012).Glyco-engineered therapeutic antibodies either bear oligosac-charides modified by bisecting GlcNAc,aβ1,4-GlcnAc residue attached to a coreβ-mannose residue,or lack the core fucose of the Fc oligosaccharides and have been found to exhibit significantly higher ADCC than their unmodified counterparts(Lifely et al., 1995;Shinkawa et al.,2003).These modifications of oligosaccha-rides are mainly obtained by either transfecting CHO cell line with N-acetylglucosaminyltransferase III(GnTIII)or eliminat-ing its intrinsicα-1,6-fucosyltransferase(FUT8)activity.Alter-native expression systems such as Sf21insect cells,resulting in fucosylated paucimannosidic N-linked glycosylation,have been suggested to elicit an enhanced ADCC and have been investigated with a chimeric CD19antibody at our institution(Lang et al., 2004;Barbin et al.,2006).Several other glyco-engineered antibod-ies targeting a variety of different tumor associated antigens like CD19,CD20,EGFR,and GD2are currently investigated in early clinical studies(Robak,2009;Navid et al.,2010;Paz-Ares et al., 2011;Ward et al.,2011).All glyco-engineered antibodies in clini-cal trials have been reviewed in more detail elsewhere(Beck and Reichert,2012).Recently,the C–C chemokine receptor4(CCR4) targeting glyco-engineered antibody mogamulizumab has been approved in Japan for use in patients with relapsed and refrac-tory CCR4-positive adult T cell leukemia/lymphoma(ATL)(Beck and Reichert,2012).Clinical superiority of these third-generation mAbs over clinically established therapeutic antibodies remains to be shown and may further portend the key role of ADCC for clinical use.CONCLUSIONThe studies discussed here clearly demonstrate a substantial role of ADCC in vitro and in mouse tumor models.However,the direct in vivo effect of ADCC in tumor reactivity in humans remains to be shown since no therapeutic antibody with ADCC as single mechanism of action has been investigated in clini-cal trials to date.Conflicting results have been obtained about the role of FcγRIIIa-V158F polymorphism in mAb treatment. Several studies have shown a predictive value,which underlines。
