纯化和标记抗人轻链β2m单克隆抗体的方法

背景:通过杂交瘤细胞株接种小鼠腹腔可获得含大量抗体的腹水,但以往纯化腹水中单克隆抗的方法较复杂,不易操作。 目的：制备、纯化和标记抗人类白细胞抗原Ⅰ类分子轻链的单克隆抗体,以检测肿瘤细胞表面的人类白细胞抗原Ⅰ类分子的表达。 方法：将杂交瘤细胞接种至小鼠腹腔,获得含抗人轻链β2m抗体的腹水,用改良的辛酸-硫酸铵方法纯化腹水,将纯化后的单克隆抗体标记异硫氰酸荧光素(FITC),标记后的抗体用于检测外周血单个核细胞、表达空载人类白细胞抗原A2分子的T2细胞和白血病K562细胞表面的人类白细胞抗原Ⅰ类分子,并用流式细胞仪和荧光显微镜观察人类白细胞抗原Ⅰ类分子的表达。 结果与结论：纯化后的抗人轻链β2m-FITC单克隆抗体纯度为96%。流式细胞检测结果表明,人类白细胞抗原Ⅰ类分子在外周血单个核细胞表面高表达,在表达空载人类白细胞抗原A2分子的T2细胞表面低表达,而在白血病K562细胞表面不表达。结果证实,用改良的辛酸-硫酸铵方法纯化腹水以此制备的抗人轻链β2m-FITC能有效区别不同细胞表达人类白细胞抗原Ⅰ类分子的强弱,其纯化方法简便易行。     

腹水型单克隆抗体纯化方法的研究

目的：比较不同纯化方法对腹水型抗体的纯化效果,探索出最适合实验室抗体生产的纯化方法。方法制备的 IgG1单克隆抗体腹水（4-D10）分别利用两步硫酸铵沉淀法（AS 法）、辛酸-硫酸铵沉淀法（CA-AS法）、辛酸-硫酸铵沉淀法联合 DEAE 阴离子交换层析法与辛酸-硫酸铵沉淀法联合蛋白 G 亲和层析法纯化处理后,经蛋白纯度、回收率、抗体免疫活性鉴定分析后,比较不同的纯化方法对腹水型抗体的纯化效果。结果① AS 法的蛋白纯度为25%,低于 CA-AS 法（44%）;AS 法回收率为63%,高于 CA-AS 法（41.8%）;比较抗体效价表明,AS 法（1.024×106）与 CA-AS 法（1.024×106）两者相当。②粗提后纯化效果表明,蛋白 G亲和层析法回收率明显降低,DEAE 纯品虽纯度略低,但回收率较高,且效价（5.12×105）高于蛋白 G 亲和层析法（1.28×105）。结论 CA-AS 联合 DEAE 离子交换法是适合实验室生产单抗的低成本、纯化效果和回收效果较佳的方法。     

重组灵芝免疫调节蛋白(rLZ-8)单克隆抗体的制备及鉴定

目的:制备重组灵芝免疫调节蛋白(rLZ-8)单克隆抗体,为rLZ-8的药效学及药代动力学研究奠定基础.方法:以纯度99%的rLZ-8免疫BALB/c小鼠;应用常规的细胞融合技术建立一种能够稳定分泌抗rLZ-8单克隆抗体的杂交瘤细胞株;采用小鼠腹腔接种法制备腹水;Protein A Sepharose 亲和层析柱在AKTA纯化仪上对抗体进行纯化;间接ELISA方法测定单克隆抗体的效价;Western blot胶片曝光方法对rLZ-8单克隆抗体特异性进行分析.结果:筛选出2株可特异性分泌抗rLZ-8单克隆抗体的杂交瘤细胞株.分别命名为clone13-2-3和clone11-4-4.其抗体亚型分别为IgG1亚型和IgG2a亚型.腹水抗体效价分别为1:12 000和1:7 500,细胞培养上清效价分别为1:3 000和1:2 800.Western blot检测证明这两株杂交瘤细胞所分泌的单克隆抗体均具有良好的特异性.结论:成功制备出较高效价和较高特异性的鼠抗rLZ-8的单克隆抗体.     

抗人Flt-1单克隆抗体的制备和活性鉴定

目的:制备小鼠抗人血管内皮生长因子受体-1(Flt-1)的单克隆抗体(mAb),并鉴定其免疫学特性。方法:以重组人Flt-1胞外Ⅲ区蛋白为抗原,通过经典的杂交瘤制备和活性筛选方法建立能稳定分泌抗Flt-1蛋白的mAb杂交瘤细胞株。结果:经传统的小鼠腹水型抗体的制备和纯化方法获得了高纯度的抗人Flt-1胞外Ⅲ区蛋白的mAb。ELISA方法测定出该抗体的免疫球蛋白亚型为IgG1,轻链为κ链。West-ern blot结果显示该抗体能特异性地识别重组人Flt-1胞外Ⅲ区蛋白,FACS结果表明该抗体能结合到Flt-1阳性的脐静脉内皮细胞和K562/A02细胞表面,并呈现出抗体浓度依赖性。结论:成功建立了1株能够稳定分泌抗重组人Flt-1胞外Ⅲ区蛋白的mAb细胞株XA12,为今后进一步开展Flt-1及其胞外Ⅲ区蛋白的生物学功能研究以及基因工程抗体研究奠定了基础。     

鲢鱼小清蛋白的分离纯化及其单克隆抗体的制备与鉴定

目的:制备抗鲢鱼主要过敏原小清蛋白的单克隆抗体,并对其基本特性进行鉴定。方法:采用硫酸铵盐析、离子交换柱层析和凝胶过滤柱层析等方法纯化鲢鱼小清蛋白;以纯化的小清蛋白免疫BALB/c小鼠,采用杂交瘤技术制备抗鲢鱼小清蛋白单克隆抗体;通过ELISA法确定抗体亚型;通过腹水诱生法大量制备单克隆抗体;以Protein G Sepharose亲和层析柱纯化制备的单克隆抗体;运用Western blot鉴定单克隆抗体的特异性;以ELISA法分析单克隆抗体的结合位点。结果:从100 g鲢鱼肌肉中可获得约30 mg高纯度小清蛋白;SDS-PAGE结果表明,得到的抗小清蛋白单克隆抗体(A4-C1)纯度较高,亚类为IgG1;Western blot结果显示,A4-C1只与鱼肉粗提物中的小清蛋白产生反应,特异性良好;ELISA分析表明,制备的抗鲢鱼小清蛋白单克隆抗体与商品化抗蛙小清蛋白单克隆抗体(PARV-19)的结合位点可能具有很大部分的重叠,或者存在较大的空间位阻效应。结论:研究中制备的杂交瘤细胞株能稳定分泌高特异性的抗鲢鱼小清蛋白单克隆抗体,可用于后续淡水鱼类小清蛋白检测方法的建立。     

抗人AFP单抗及多抗与丝裂霉素联接物对肝癌细胞的杀伤作用

用本室制备的分泌IgG AFP McAb的杂交瘤株G2及G10,接种于BALB/c小鼠腹腔,取其腹水经硫酸铵及Sepharose 4B柱亲和层析纯化,获得抗人AFP单抗。将马抗人AFP血清经硫酸铵及Sepharose 4B柱亲和层析提取AFP抗体IgG,得到AFP多抗。将纯化     

重组人α干扰素单克隆抗体的研制及其应用

目的　研制抗干扰素的单克隆抗体 (McAb)及其应用。方法　应用杂交瘤技术 ,获得 4 0株抗重组人α干扰素的单克隆抗体细胞株 ;用ELISA方法检测腹水滴度 ,用辛酸法纯化McAb。结果　 4 0株细胞中 2E9、4G1能稳定分泌抗重组人α1b干扰素的单克隆抗体 ,2C9为抗重组新型干扰素 ,2A7、4G10分泌抗重组人α干扰素 (α1b、α2b、α2a、)和重组集成干扰素、重组新型干扰素的单克隆抗体细胞系 ;体外连续传代 6个月 ,分泌抗体能力不变 ,特异性专一。 5株单克隆抗体均为IgG。采用辛酸方法提纯抗体纯度达到 95 %以上。粗制的重组人α干扰素经 4G10单克隆抗体亲和层析柱提纯后 ,获得的干扰素纯度 95 %以上 ,平均收率 93% ,残余鼠IgG含量 <10 0ng 剂量 (5 0 μg)。 2C9单克隆抗体亲和层析柱适用于纯化新型干扰素。结论　 4G10单克隆抗体亲和层析柱可以应用于大规模重组人α干扰素生产。     

抗重组人γ干扰素单克隆抗体的纯化研究

取本实验室制备的抗重组人γ干扰素单克隆抗体(rHu IFN-γ/McAb)A_3和B_3E_7粗制品(BALB/c小鼠腹腔分泌液),分别用饱和硫酸铵盐析法和葡萄球菌A蛋白(SPA)亲和层析法进行纯化。结果发现,虽两者都能部分纯化A_3和B_3E_7-McAb,但后者(SPA亲和层析法)的纯化效果比前者(硫酸铵盐析法)好。纯化后的产品经冷冻干燥后置低温贮存,其活性(抗体滴度)不受影响.     

抗人肝再生增强因子单克隆抗体的研制

目的　利用纯化的重组人肝再生增强因子(hALR)制备抗hALR的单克隆抗体,建立hALR的检测方法。方法 采用杂交瘤技术制备单克隆抗体,经ELISA和免疫印迹证明其特异性。结果获得了4株分泌抗hALR特异性抗体的杂交瘤 细胞系;无血清培养液效价为1×10-2,腹水效价为1×10-5;亚类鉴定表明2株单克隆抗体为IgGl,另2株为IgG2b;免疫印迹 显示抗体结合抗原的分子量与hALR相符,为特异性抗hALR抗体。结论通过杂交瘤技术,获得了抗hALR的单克隆抗体 为以后的工作奠定了基础。     

应用于胶体金免疫层析的MDMA单克隆抗体的制备与鉴定

目的：制备高特异性的抗3,4亚甲二氧基甲基苯丙胺（MDMA）单克隆抗体,用于建立快速检测MDMA的胶体金免疫层析方法。方法：用MDMA人工抗原免疫BALB/c小鼠,将小鼠脾细胞与骨髓瘤细胞SP2/0融合,经亚克隆筛选得到稳定分泌抗MDMA单克隆抗体的杂交瘤细胞株。制备腹水,辛酸-饱和硫酸铵法纯化得到抗MDMA单克隆抗体（mAb）,并用胶体金免疫层析筛选出适用的抗MDMA单克隆抗体（mAb）,并对其进行特异性、纯度、亚类的鉴定分析。结果：经多次亚克隆后筛选得到4C10、4D10、7D11、8D4 4株分泌抗MDMA单克隆抗体的杂交瘤细胞株。其中细胞株8D4分泌的抗体适用于胶体金免疫层析。结论：成功筛选出能稳定分泌mAb的细胞株,为MDMA快速检测试剂的研制提供了关键材料。     

A monoclonal antibody to tissue plasminogen activator with affinity for the Kringle regions: Implications for fibrin affinity and enzymatic mechanism

An IgA class monoclonal antibody (2:2 G:5) to tissue plasminogen activator (t-PA) was raised by standard immunisation and cloning procedures. It was purified from ascites using ammonium sulfate precipitation, Sepharose-protein A chromatography, Sepharose-lysine treatment, DEAE Affi-Blue ion exchange chromatography and affinity chromatography on Sepharose-t-PA. After purification, the existence of free light and heavy chains and light—chain dimers, under denaturing but non-reducing conditions, indicated that the antibody preparation contained IgA type 2.The antibody inhibited t-PA mediated plasminogen activation but not amidolytic activity on low molecular weight chromogenic substrates. The antibody precipitated t-PA both in agarose double-diffusion and in solution. This suggests that t-PA may have two similar epitopes, and these are likely to be situated in the kringle regions. Kringle-binding ligands, e.g. arginine, inhibits the precipitation reaction, with half-maximal inhibition at 100 mmol. At this concentration of arginine, one-chain t-PA is also dissociated from fibrin, evidenced by a decrease in the fibrin-caused stimulation of amidolytic activity. Thus, the antibody might be used to study the fibrin binding of tissue plasminogen activator.     

Isolation of decay-accelerating factor (DAF) from rabbit erythrocyte membranes

A simple, non-chromatographic purification procedure for monoclonal antibodies from mouse ascites fluid is described. This procedure, which is rapid, inexpensive, and has high capacity involves the precipitation of contaminating proteins with caprylic acid followed by precipitation of immunoglobulin using ammonium sulfate. This two-step procedure is shown to be effective for the purification of various immunoglobulins including IgG1, IgG2a and IgG2b. In the present report, more than 30 monoclonal antibodies directed against cytochrome P450 isozymes have been purified by this method and characterized.     

一种利用HCIC快速纯化抗rhTF_(243)单克隆抗体方法的研究

目的:建立从小鼠腹水中快速纯化抗人重组组织因子243(recombine human tissue factor243,rhTF243)单克隆抗体(monoclonal antibody,mAb)的方法。方法:含抗rhTF243单克隆抗体的腹水经离心、过滤及缓冲溶液变换等预处理后,先经疏水电荷诱导层析纯化处理,去除大部分杂蛋白,再经Protein A-Sepharose CL-4B亲和层析柱进一步纯化。结果:经两步纯化后获得抗rhTF243单克隆抗体,其生物学活性高、纯度大于95%,抗体效价保持良好,抗体总回收率达73%,且具有明显的抗促凝作用。结论:建立的单克隆抗体纯化方法简便、高效,所得mAb的纯度高、生物学活性好。     

高效液相色谱纯化抗肾综合征出血热病毒血凝素单克隆抗体及特性鉴定

本文报告从BALB/c小鼠免疫腹水及该腹水经40％饱和硫酸铵盐析沉淀的γ球蛋白用高效液相色谱层析技木(HPLC)纯化、制备抗肾综合征出血热病毒血凝素单克隆抗体。HPLC一步法对IgG1的回收率为52％,纯度97.4％;HPLC二步法回收率为67％～73％,纯度98.1％;盐析法回收率为85％,纯度≥70％。间接免疫荧光法测定HPLC纯化样品(二步法)的比活性提高49～51倍,血凝抑制滴度为1:5120。     

Isolation and Purification of Murine Monoclonal IgG1 Employing Specific Immuno-Affinity Chromatography

Studies were performed to determine if murine monoclonal immunoglobulin G1 (IgG1) could be purified from ascites fluid employing specific immuno-affinity chromatography. Murine polyclonal IgG was first removed from the ascites fluid by passage over immobilized protein A at pH 7.0. Analysis of the ascites fluid after this procedure revealed that murine monoclonal IgG1 did not bind to the protein A under the conditions employed. Additional analyses revealed that murine polyclonal IgG bound to and could be eluted from the immobilized protein A. Subsequent passage of the ascites fluid through an immunoadsorbent containing sheep antibody to murine monoclonal IgG1 revealed that the murine monoclonal IgG1 isotype was specifically removed. Analyses of the immunoglobulin eluted from the immuno-affinity matrix revealed the presence of murine monoclonal IgG1 with purities equal to or greater than 95%.     

生物素化抗细胞因子单克隆抗体的制备

目的 探讨生物素化单克隆抗体的制备方法。方法 应用经超滤、硫酸铵沉淀、ProteinG亲和层析纯化的来源于杂交瘤细胞培养上清中的大鼠抗小鼠IL-5、IL-4和IFN-γ单克隆抗体，以每mg抗体加入生物素制剂80ug室温反应60min，其反应液经SephadexG-25层析纯化，然后用生物素-亲和素ELISA法测定所制备的生物素化抗体活性。结果 该法制备的生物素化抗体活性高，用于检测感染巴西钩虫的IL-5转基因小鼠和非转基因小鼠的血清标本敏感性好。结论 该生物素化抗体的抗备方法具有制备简单、稳定性好等优点。     

抗SARS病毒N蛋白单克隆抗体的制备和初步应用

目的 制备抗SARS病毒N蛋白的单克隆抗体并研究其初步应用。方法 用基因重组N蛋白免疫小鼠，取免疫后的鼠脾细胞与骨髓瘤细胞融合，筛选分泌抗SAPS病毒N蛋白单克隆抗体细胞株。将阳性细胞株接种小鼠腹腔制备单克隆抗体腹水并对抗体进行纯化，分析纯化抗体的相对亲和力。选择亲和力较高的抗体制备检测SARS病毒抗原的酶联免疫诊断试剂，并对其敏感性和特异性进行分析。结果 共获得11株单克隆抗体细胞株，其中3株单抗与N蛋白具有较高的亲和力，4株纯化单抗与N蛋白反应很弱，其余4株单抗介于两者之间。用亲和力较高的单抗制备检测SARS病毒抗原的诊断试剂，其敏感性可达31PFU／ml，而且与其他呼吸道病毒无交叉反应。结论 该试剂特异性较好，可用于SARS病毒抗原的检测，其敏感性仍需用临床急性期样品进行评价。     

Activation of hemolytic complement by mouse monoclonal IgG1 antibody: comparison with rabbit IgG

We investigated the ability of a mouse anti-hapten monoclonal IgG1 antibody (Ab) to bind to cell-bound specific hapten and to fix and activate C1 and thus the lytic sequence of complement (C). In a comparative study with polyclonal rabbit anti-hapten IgG Ab, we found that about 6 times more monoclonal Ab molecules than polyclonal were necessary for the generation of 1 hemolytic site/cell: the data were interpreted to mean that a cluster of four cell-bound monoclonal Ab molecules was necessary to bind C1 and activate C-mediated hemolysis. Experiments performed under conditions of low density of cell-bound hapten and excess of antibody showed that both monoclonal and polyclonal IgG Abs were able to react only with 20-30% of the cell-bound hapten and that both Abs recognized the same hapten specificity. We also found that even though monoclonal IgG1 Ab was able to bind strongly to a protein A-Sepharose column and could be eluted only by a low-pH buffer, the purified Ab, when bound to cell surface hapten, showed a weak ability to react with free protein A.     

A simple, non-chromatographic procedure to purify immunoglobulins from serum and ascites fluid

A simple, two-step procedure to purify the immunoglobulin G (IgG) fraction from mammalian sera and ascites fluid is described. In the first step, albumin and other non-IgG proteins are precipitated with caprylic acid (octanoic acid). In the second, the IgG fraction is precipitated with ammonium sulfate. Factors influencing the precipitation of serum proteins by caprylic acid are described, as are procedural modifications to purify the IgG fraction from sera with a high lipid content. The procedure can be used to purify the IgG fraction of serum from rabbit, sheep, goat, horse, rat and mouse, as well as monoclonal antibodies from mouse ascites fluid. Greater than 80% of the IgG in rabbit serum could be isolated by this procedure, with a purity equal to rabbit IgG purified by anion-exchange chromatography. In addition to its simplicity and low cost, the procedure described offers several advantages over other methods to purify IgG.