抗ssDNA单克隆抗体的研制和在检测凋亡细胞中的应用

为了制备抗单链DNA单克隆抗体和建立检测细胞凋亡的新方法 ,采用杂交瘤细胞融合技术用于筛选分泌抗单链DNA抗体的单克隆杂交瘤细胞株 ,并用斑点印迹和竞争ELISA法鉴定单抗的特异性 ,进而结合免疫组织化学和免疫荧光方法用于检测凋亡细胞。通过筛选得到单克隆杂交瘤细胞株B17,其分泌的抗体与单链DNA结合而与双链DNA无交叉反应 ,用此单抗建立的凋亡细胞检测方法能够检测出凋亡细胞 ,区分非凋亡细胞和坏死细胞。实验结果表明 ,成功地获得一株分泌特异性抗单链DNA抗体的单克隆杂交瘤细胞株 ,以此建立的凋亡细胞检测方法特异性高、敏感性强     

鼠抗人PD-L1单克隆抗体的研制和生物学活性鉴定

目的 研制鼠抗人PD-L1功能性单克隆抗体,并对其生物学活性进行鉴定.方法 以前期原核表达的人硫氧还原蛋白-（PD-L1）融合蛋白为免疫原免疫BALB/c小鼠,利用杂交瘤技术进行细胞融合,Western-Blot和酶联免疫吸附试验（ELISA）筛选阳性杂交瘤细胞,竞争抑制法ELISA实验鉴定抗体的特异性亲和力,小鼠腹水法作大量抗体制备.结果 获得4株能够稳定分泌特异性抗PD-L1抗体的杂交瘤细胞,经验证所分泌的抗体具有较强的特异性亲和力,经过大量抗体制备和纯化获得效价大于1∶32000的纯化抗体;同时获得1株能稳定分泌抗硫氧还原蛋白抗体的杂交瘤.结论 成功制备了鼠抗人PD-L1单克隆抗体,为下一步应用研究奠定了基础.     

用于制备抗体芯片的抗人甲胎蛋白单克隆抗体的制备及特性分析

目的：制备抗人甲胎蛋白（AFP）单克隆抗体（mAb），并用于制备抗体芯片。方法：利用杂交瘤技术建立能稳定分泌抗人AFPmAb的杂交瘤细胞株；对抗体的亲和力、特异性等特性进行分析；利用抗体相加实验，双抗体夹心ELISA、胶体金免疫层析实验以及抗体芯片技术对抗体表位及其配对情况进行分析研究。结果：共获得16株稳定分泌抗人AFPmAb的杂交瘤细胞株，从中筛选出多组性能优良的配对抗体，结合抗体芯片技术，最终筛选出适合制备抗体芯片的配对抗体。结论：当抗体包被材料或包被方法发生改变时，会引起mAb构象发生变化，从而影响抗体的配对效果。因此，筛选适合制备抗体芯片的配对mAb时，需要对mAb的特性进行综合分析，选取特异性好，亲和力高的mAb进行配对筛选。     

一种狂犬病实验室诊断用单克隆抗体制备新路线的探索

目的 探索采用合成肽作为免疫原制备狂犬病实验室诊断用单克隆抗体的可行性.方法 以狂犬病病毒CVS-11核蛋白355-369位B细胞线性抗原表位合成肽与钥孔戚血蓝蛋白（Keyhole Limpe hemocyanin,KLH）大分子耦联后免疫BALB/c小鼠,利用经典杂交瘤细胞技术制备单克隆抗体.采用间接酶联免疫吸附试验（enzyme-linked immunosorbent assay,ELISA）和间接荧光试验（indirect fluorescent assay,IFA）筛选和鉴定杂交瘤细胞株.结果 经过对杂交瘤细胞株上清的间接ELISA和IFA筛选获得阳性杂交瘤细胞株2B1D11,该杂交瘤细胞株产生的抗体经纯化后在IFA中可以有效检出感染犬脑组织和BHK-21细胞的狂犬病病毒.结论 采用合成肽作为免疫原制备狂犬病实验室诊断用抗体在技术上是可行的.     

EBV-杂交瘤技术制备抗乳癌人单抗的研究

本研究用EBV-杂交瘤技术制备抗乳癌人单抗获得初步成功。实验中首先预选出病人血清对肿瘤相关抗原有强阳性反应的乳癌患者,取其引流区淋巴结细胞,去除T细胞。在体外用EBV转化。筛选出分泌阳性抗体的B细胞,扩增后与一株人-鼠骨髓瘤杂交株HMD-33融合,用含HAT-ouban 1640培基进行选择培养。融合后两周左右见有杂交瘤生长,融合率为38％,从中获得16株稳定分泌抗体的杂交瘤,抗体类型75％为人IgM余为人IgG或混合型,上清     

自身抗体联合体液免疫检测在SLE中的应用价值

目的 探讨联合检测自身抗体、免疫球蛋白和补体在系统性红斑狼疮(SLE)诊断和病情判断中的应用价值.方法 选取SLE患者54例、其他自身免疫性疾病患者32例和正常对照30例,采用间接免疫荧光法测定抗核抗体(ANA)、免疫印迹法测定抗核提取物抗体(抗ENA抗体)、散射免疫比浊法测定免疫球蛋白和补体C3、C4.结果 SLE患者的ANA、抗dsDNA、抗Sm、抗核小体、抗U1-nRNP、抗核糖体P蛋白、抗组蛋白抗体的检测阳性率分别为87.04％、59.26％、27.78％、29.63％,37.04％、12.96％、27.78％;SLE活动组中抗dsDNA和抗核小体抗体的阳性率高于SLE非活动组,差异具有统计学意义(P＜0.05);SLE活动组IgG、IgA、IgM水平高于正常对照组,C3、C4水平低于正常对照组,差异具有统计学意义(P＜0.01).结论 自身抗体联合免疫球蛋白和补体检测对SLE患者的临床诊断和病情判断有良好的参考价值.     

一次融合同时获得抗独特型和抗抗独特型单克隆抗体的杂交瘤

本文在研制带有HBsAg表位内影象的单克隆抗独特型抗体的过程中,用抗-HBs单克隆抗体(Ab_1)免疫同系鼠,除筛选分泌Ab_2β的杂交瘤细胞外,还同时设计了筛选分泌Ab_3的杂交瘤。结果在一次免疫,一只免疫鼠的脾脏细胞,一次融合实验中,同时获得了分泌Ab_2β及Ab_3抗体的杂交瘤细胞株。本文报告筛选Ab_3的方法及对Ab_3所作的免疫化学鉴定。结果获得一株分泌Ab_3单克隆抗体的杂交瘤细胞株,命名为M4。证明Ab_3具有Ab_1的特异性。这一结果不仅提示独特型网络的确在同一个体内客观存在,而且也为研制单克隆抗独特型抗体杂交瘤提供了一条简单、经济、事半功倍的经验。     

抗人红细胞膜抗原非凝集型单克隆抗体的研制及特性鉴定

目的:制备抗人红细胞膜抗原的非凝集型单克隆抗体(mAb)并鉴定其特性。方法:应用杂交瘤技术,以人O型红细胞膜抗原免疫BALB/c小鼠。取免疫小鼠的脾细胞与Sp2/0骨髓瘤细胞融合,用聚凝胺试管法筛选识别红细胞表面共同抗原的抗体,玻片凝集实验剔除凝集型抗体(完全抗体),再将分泌非凝集型mAb(不完全抗体)的杂交瘤细胞株用有限稀释法克隆化3次。对杂交瘤细胞的稳定性和mAb的特性进行鉴定。结果:获得1株可稳定分泌mAb的杂交瘤细胞2E8。mAb2E8为IgG1类,可特异性地识别红细胞膜上的H抗原,没有种属交叉血凝反应。杂交瘤细胞的培养上清与人的A、B、AB和O型红细胞均能产生强凝集,凝集效价为1∶1024,腹水mAb的凝集效价达到1∶64×106。mAb的亲和力用凝集试验检测,出现血凝的时间为7s,3min以内凝块>1mm。结论:成功地制备了针对红细胞膜H抗原的非凝集性mAb,此mAb的凝集效价、相对亲和力及特异性均较良好,为构建双特异性抗体奠定了基础。     

固定杂交瘤细胞间接免疫荧光法检测抗独特型抗体

<正> 在制备多克隆抗独特型抗体(简称抗Id抗体)过程中,检测抗Id抗体通用方法是用纯化独特型抗体(简称 Id 抗体)的 ELISA或RIA。由于分泌Id抗体的杂交瘤细胞表面表达有均一的Id抗体分子,Kennedy等人曾采用分泌Id抗体的新鲜杂交瘤细胞间接免疫荧光试管法检测抗Id抗体的活性及特异性,以节省纯化Id抗体的用量和提高初步检测的速度。我们在检测自制的多克隆抗Id抗体的过程中,对该法进行了改进,即用固定杂交瘤细胞间接免疫荧光玻片法检     

人博卡病毒VP2蛋白单克隆抗体的制备

目的 表达纯化人博卡病毒( human Bocavirus,HBoV) VP2蛋白,采用杂交瘤方法制备抗HBoV VP2蛋白的单克隆抗体.方法 应用原核表达载体pET-30a和大肠埃希菌表达VP2蛋白,并用固定化金属亲和层析,纯化后的蛋白作为抗原免疫BALB/c小鼠,利用杂交瘤技术和间接ELASA方法筛选阳性的杂交瘤细胞,并对单克隆抗体进行分型检测和滴度测定.结果 表达并纯化获得了重组HBoV VP2蛋白,利用杂交瘤技术得到单克隆IgG抗体,抗体效价达到1∶4×105.结论 利用HBoV VP2蛋白免疫制备了单克隆抗体,并具有较高的效价.本研究为快速诊断和研究HBoV打下基础.     

Polyspecific reactivity of a murine monoclonal antibody that binds to nuclear matrix-associated, chromatin-bound autoantigens

To investigate polyspecific autoantibody interactions, we have characterized the binding of a cloned murine monoclonal IgM antibody termed (RTE-23) of strain BALB/c origin. By indirect immunofluorescence this antibody displayed a nuclear speckled and peripheral pattern in interphase cells from human and rodent cell lines. In contrast, in mitotic cells, antibody RTE-23 bound to the periphery of individual chromosomes. Immunoblot analysis of soluble and insoluble nuclear proteins from purified rat fibroblast nuclei showed that antibody RTE-23 bound to molecules of 28, 29, and 33 kDa. Furthermore, antibody RTE-23 demonstrated marked polyspecificity and reacted with cytoskeletal proteins (vimentin, keratin, actin), single-stranded DNA, specific synthetic polynucleotides, and cardiolipin. Antibody RTE-23 also showed a lupus anticoagulant-like activity. Screening of sera of autoimmune disease patients with antinuclear antibodies revealed two patients, both with SLE, whose sera blocked antibody RTE-23 binding to nuclei and recognized nuclear proteins identical to those recognized by antibody RTE-23. These results suggested that antibody RTE-23 displays a pattern of self-antigen binding that is represented as well in SLE patient sera.     

抗主要组织相容性相关蛋白MICA / B 的单克隆抗体制备及应用

目的:制备抗主要组织相容性相关蛋白A/ B(MICA/ B)的单克隆抗体并对其特异性进行验证。方法:以重组MICA*012 蛋白免疫小鼠后将其脾细胞与SP2/0 细胞进行融合和筛选得杂交瘤细胞株,并用ELISA 对其中9B10 细胞株产生的单克隆抗体进行效价检测以及通过Western blot、Luminex、免疫荧光对其特异性进行检测。结果:获得6 株杂交瘤细胞株,其中9B10 细胞株产生单克隆抗体(mAb)9B10 的最低反应浓度为0.02 ng/ μl,且mAb 9B10 可应用于Western blot、Luminex 和免疫组化荧光试验对MICA 和MICB 分子的检测。结论:成功获得可同时检测MICA 和MICB 表达的单克隆抗体9B10。     

A human monoclonal anti-DNA antibody derived from a patient with polymyositis having the common lupus 16/6 idiotype

A human IgM monoclonal antibody (Pol-1, SA-1) was generated by the human hybridoma technique from the peripheral blood lymphocytes (PBL) of a patient with active polymyositis. The antibody was found to bind to ssDNA, dsDNA, poly(I) and poly(G) and to carry the common lupus anti-DNA antibody idiotype (16/6 Id). Another human IgM monoclonal antibody (Pol-2, SA-2) produced by similar methods from the PBL of the same patient while in remission lacked the ligand-binding capacities of Pol-1 SA-1 and did not have the 16/6 Id. Analyses of 19 sera samples from patients with polymyositis showed no antinuclear antibodies, excluding a 40% prevalence of the 16/6 Id. The serum of the patient whose lymphocytes were employed to generate the hybridoma was negative for anti-DNA activity as well as for the 16/6 Id. This study suggests that the hybridoma technique may enable expression of dormant idiotypic affinities which do not normally appear in sera.     

A central anti-DNA idiotype in human and murine systemic lupus erythematosus

The monoclonal anti-DNA autoantibody A52 (IgG2b) was obtained from a (NZB X NZW)F1 (B/W) hybridoma. Two rabbits were immunized with the pure monoclonal antibody and produced anti-idiotypic (Id) antibodies. The purified anti-Id reacted with three different B/W monoclonal anti-DNA antibodies at or close to their DNA binding sites. Moreover, the rabbit antibodies had a profound inhibitory effect on the polyclonal anti-DNA activity in the majority of sera derived from B/W mice and human systemic lupus erythematosus (SLE) patients. The A52 IgG must, therefore, represent a major cross-reactive Id of anti-DNA immunoglobulins. In addition, the rabbit anti-Id antibodies may act as the "internal image" of antigen and should prove useful in modulation of the autoimmune response to DNA in SLE.     

Binding of cytoskeletal proteins by monoclonal anti-DNA lupus autoantibodies

Monoclonal anti-DNA antibodies produced by hybridomas derived from MRL-lpr/lpr mice and human lupus patients were found to bind to the cytoskeleton of mink lung cells. When tested by indirect immunofluorescence, 17/29 human monoclonal anti-DNA antibodies reacted with the cytoskeleton; 4 of the 29 also produce antinuclear reactions with epithelial cells. The cytoskeletal staining was not inhibited by prior treatment of the cells with DNase, but it was completely blocked by prior incubation of the monoclonal antibodies with DNA and other nucleic acids. The ability of the polynucleotides to inhibit the cytoskeletal staining corresponded to their ability to bind to the antibodies in competitive immunoassays. An (Fab')2 preparation of a monoclonal antibody bound to the cytoskeleton as well as the whole immunoglobulin. The effect of colcemid on the staining pattern, the blocking effect of a monoclonal antivimentin antibody, and results with nitrocellulose blots of cellular proteins indicated that the cytoskeletal protein to which the antibodies bound was vimentin.     

Functional Property of la-Positive T Cells in Peripheral Blood from Patients with Systemic Lupus Erythematosus

Ia-positive (Ia+) T cells in peripheral blood and their functional property were examined in patients with systemic lupus erythematosus (SLE). Binding of specific monoclonal antibodies was assessed by indirect immunofluorescence. Functional study of Ia+ T cells was carried out in coculture experiments by measuring the IgG secreted into the culture supernatant. We found that the percentage of Ia+ T cells in peripheral blood from patients with SLE was raised and the rise correlated positively with serum gamma globulin and IgG level. The elevation was further increased after stimulation with DNA in vitro, indicating the presence of DNA-sensitive T cells. Functionally, Ia+ T cells acted as helper cells in spontaneous IgG synthesis of SLE B cells, and were enriched in the OKT4 subset. These results indicate that SLE T cells are activated in vivo and that the Ia+ T cells may play a crucial role in the immunoregulatory function. Accordingly, demonstration of Ia antigens on T cells by monoclonal antibody may provide a useful tool for the measurement of immunological activity in patients with SLE.     

A monoclonal antibody against migration inhibitory factor (MIF) obtained by immunization with MIF from the human lymphoblast cell line Mo

A monoclonal antibody-secreting hybrid cell line, E7, was constructed from myeloma cells and spleen cells from BALB/c mice immunized with partially purified human MIF from culture fluid of the human T-lymphoblast cell line Mo. The hybrid cell line E7 was selected by screening hybridoma cultures for their capacity to adsorb added MIF activity when assayed together with rabbit anti-mouse IgG-coupled to protein A-Sepharose. The monoclonal antibody produced by the cloned hybridoma E7 also directly neutralized MIF activity from Mo cells and two species of MIF from the culture fluid of human peripheral blood lymphocytes, but did not neutralize IFN-gamma from Mo cells and from human peripheral blood lymphocytes. This antibody reacted also with a component in phytohemagglutinin preparations with an apparent molecular weight of 60,000; however, it did not react with the active tetramer of phytohemagglutinin.     

A monoclonal anti-neuroblastoma antibody that discriminates between human nonhematopoietic and hematopoietic cell types

A murine IgG2a monoclonal antibody, termed 6-19, was characterized in terms of its ability to bind to human cell lines and tissues. The hybridoma was selected for antibody binding to multiple human neuroblastoma cultured cell lines but not to peripheral blood mononuclear cells. 6-19 binds to the cell surface of all cultured human nonhematopoietic tumor cell lines tested, to cultured human fibroblasts and endothelial cells, and to nonhematopoietic tumors of many types. It does not bind detectably to any hematopoietic cells, leukemia cells, or lymphomas. In the presence of complement, 6-19 is very cytotoxic to cultured human neuroblastoma cells but not to bone marrow granulocyte-macrophage colony-forming cells. The 6-19 monoclonal antibody may prove useful in the identification or destruction of tumor and stromal cells in bone marrow.     

A systemic lupus erythematosus-derived human hybridoma autoantibody reactive with antigens expressed on ADP-activated platelets

Hematological complications seen in systemic lupus erythematosus (SLE) patients may be caused by the binding of specific autoantibodies to platelets, but the epitopes on platelets responsible for antibody binding and the mechanisms by which autoantibodies induce hemostatic abnormalities in SLE patients remain unknown. We have previously demonstrated that polyspecific platelet-binding antibodies can be derived from SLE patients. In the present study, we have characterized an SLE-derived polyspecific hybridoma antibody, 9604, which was previously shown to be strongly cytotoxic to platelets in vitro and to have weak lupus anticoagulant activity. We demonstrated that this antibody does not bind to fixed intact platelets in an enzyme-linked immunoassay (ELISA), but does react with lysed, washed or ADP-activated platelets. By Western blotting analysis, antibody 9604 was unique among other platelet-binding autoantibodies in that it reacted mainly with polypeptides of approximately 200,000 and 32,000 molecular weight (MW) in platelets. In blots of endothelial cell proteins, 9604 reacted with a band of approximately 200,000 MW, but no 32,000 MW reactive band was observed. Based on these findings, we postulate that antibody 9604 may bind to a protein or proteins of 32,000 MW exposed on the platelet surface during activation. To our knowledge, this is the first demonstration of a human hybridoma monoclonal antibody derived from an SLE patient which distinguishes between activated and resting platelets. Further characterization of the proteins recognized by this autoantibody may provide insight into the mechanisms responsible for the production and pathogenesis of anti-platelet autoantibodies in patients with SLE.     

Neutralization of lymphocyte immortalization by different strains of Epstein-Barr virus with a murine monoclonal antibody.

A murine monoclonal antibody was raised against the B95-8 strain of Epstein-Barr virus (EBV), which was isolated from a case of mononucleosis after blood transfusion (Hoffman et al. Proc. Natl. Acad. Sci. U.S.A. 77:2979, 1980). We provide evidence that neutralization of immortalization by this monoclonal antibody is virus specific, since its potency was inversely related to the dose of challenge virus. Furthermore, the monoclonal antibody recognized antigens on viruses grown in human as well as in marmoset cells. We show that this monoclonal antibody neutralized three other transforming strains of EBV originating, respectively, from American patients with mononucleosis and fatal polyclonal lymphoma and from an African child with Burkitt lymphoma. However the antibody did not neutralize or detect antigens by immunofluorescence in the W91 strain of EBV. The hybridoma antibody did neutralize other EBV strains derived from the same Burkitt lymphoma cell line (Nyevu), as was the case with the W91 strain. This monoclonal antibody provides clear evidence of antigenic differences on the surface of EBVs and will ultimately prove useful in defining the antigenic site on EBV which elicits neutralizing antibody.