{"title":"[IgM Antibody against IgG Antibody Binding to Antigen, So-Called Anti-Antibody, Reacts Mainly with F (ab')₂ Fragment Possessing Antibody Activity].","authors":"Tatsuya Matsuura, Aya Imamura, Toshiyuki Ota","doi":"","DOIUrl":null,"url":null,"abstract":"<p><strong>Objective: </strong>To develop enzyme-linked immunosorbent assay (ELISA) for measurement of IgM antibody (anti-antibody) against human IgG antibody that is binding to antigen, to distinguish anti-antibody from other antiglobulins, e.g. rheumatoid factor (RF), and to search their localization of epitope on IgG molecule.</p><p><strong>Methods: </strong>We chose purified human IgG anti-dsDNA antibody from a patient with systemic lupus erythematosus as IgG antibody and calf thymus dsDNA as antigen. IgG F (ab')₂ fragment was obtained by digestion of the IgG with pepsin. Those IgG and IgG F (ab') 2 with anti-dsDNA antibody were reacted with pre-coated dsDNA and formed immune complex on ELISA plate. On the other hand we prepared ELISA plate on which those IgG and IgG F (ab') 2 were coated directly for measurement of IgM RF and IgM antihinge antibody. Twenty-three sera from patients with rheumatoid arthritis were tested.</p><p><strong>Results: </strong>Correct IgM anti-antibodies were obtained after subtraction of absorbance of IgM anti-dsDNA anti- bodies. Remarkable correlation between IgM anti-antibodies obtained by using whole IgG and those by using IgG F(ab')₂(n=23, r²=0.914, p=1.11X10-12). There were correlations neither between IgM antiantibodies and IgM RF(n=23, r²=0.001, p=0.889) nor between IgM antiantibodies and IgM antihinge antibodies (n=23, r²=0.063, p=0.249).</p><p><strong>Conclusions: </strong>IgM molecule with anti-antibody specificity seems to be different from IgM RF and IgM antihinge antibody. Moreover, epitope recognized by IgM anti-antibody seems to localize on IgG F (ab') 2 but not on hinge region. [Original].</p>","PeriodicalId":21457,"journal":{"name":"Rinsho byori. The Japanese journal of clinical pathology","volume":"65 1","pages":"13-18"},"PeriodicalIF":0.0000,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Rinsho byori. The Japanese journal of clinical pathology","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Objective: To develop enzyme-linked immunosorbent assay (ELISA) for measurement of IgM antibody (anti-antibody) against human IgG antibody that is binding to antigen, to distinguish anti-antibody from other antiglobulins, e.g. rheumatoid factor (RF), and to search their localization of epitope on IgG molecule.
Methods: We chose purified human IgG anti-dsDNA antibody from a patient with systemic lupus erythematosus as IgG antibody and calf thymus dsDNA as antigen. IgG F (ab')₂ fragment was obtained by digestion of the IgG with pepsin. Those IgG and IgG F (ab') 2 with anti-dsDNA antibody were reacted with pre-coated dsDNA and formed immune complex on ELISA plate. On the other hand we prepared ELISA plate on which those IgG and IgG F (ab') 2 were coated directly for measurement of IgM RF and IgM antihinge antibody. Twenty-three sera from patients with rheumatoid arthritis were tested.
Results: Correct IgM anti-antibodies were obtained after subtraction of absorbance of IgM anti-dsDNA anti- bodies. Remarkable correlation between IgM anti-antibodies obtained by using whole IgG and those by using IgG F(ab')₂(n=23, r²=0.914, p=1.11X10-12). There were correlations neither between IgM antiantibodies and IgM RF(n=23, r²=0.001, p=0.889) nor between IgM antiantibodies and IgM antihinge antibodies (n=23, r²=0.063, p=0.249).
Conclusions: IgM molecule with anti-antibody specificity seems to be different from IgM RF and IgM antihinge antibody. Moreover, epitope recognized by IgM anti-antibody seems to localize on IgG F (ab') 2 but not on hinge region. [Original].
目的:建立酶联免疫吸附法(ELISA)测定人IgG抗体与抗原结合的IgM抗体(抗抗体),区分抗抗体与其他抗球蛋白,如类风湿因子(RF),并寻找其在IgG分子上的表位定位。方法:选择1例系统性红斑狼疮患者的纯化人IgG抗dsDNA抗体作为IgG抗体,小牛胸腺dsDNA作为抗原。用胃蛋白酶酶切得到IgG F (ab’)2片段。将含有抗dsDNA抗体的IgG和IgG F (ab’)2与预包被的dsDNA反应,在ELISA板上形成免疫复合物。另一方面制备了直接包被IgG和IgG F (ab’)2的ELISA板,用于检测IgM RF和IgM抗铰链抗体。对23例类风湿性关节炎患者的血清进行了检测。结果:将IgM抗dsdna抗体吸光度相减,得到正确的IgM抗抗体。用全IgG与用IgG F(ab’)2获得的IgM抗体具有显著的相关性(n=23, r²=0.914,p=1.11X10-12)。IgM抗体与IgM RF无相关性(n=23, r²=0.001,p=0.889), IgM抗体与IgM antihinge抗体无相关性(n=23, r²=0.063,p=0.249)。结论:IgM分子具有不同于IgM RF和IgM抗铰链抗体的抗抗体特异性。此外,IgM抗抗体识别的表位似乎定位在IgG F (ab') 2上,而不是在铰链区。(最初的)。