PDF(Pubmed)
Abstract：
Antibodies to DNA are a diverse set of antibodies that bind sites on DNA, a polymeric macromolecule that displays various conformations. In a previous study, we showed that sera of normal healthy subjects (NHS) contain IgG antibodies to Z-DNA, a left-handed helix with a zig-zig backbone. Recent studies have demonstrated the presence of Z-DNA in bacterial biofilms, suggesting a source of this conformation to induce responses. To characterize further antibodies to Z-DNA, we used an ELISA assay with brominated poly(dGdC) as a source of Z-DNA and determined the isotype of these antibodies and their binding properties. Results of these studies indicate that NHS sera contain IgM and IgA as well as IgG anti-Z-DNA antibodies. As shown by the effects of ionic strength in association and dissociation assays, the anti-Z-DNA antibodies bind primarily by electrostatic interactions; this type of binding differs from that of induced anti-Z-DNA antibodies from immunized animals which bind by non-ionic interactions. Furthermore, urea caused dissociation of NHS anti-Z-DNA at molar concentrations much lower than those for the induced antibodies. These studies also showed IgA anti-Z-DNA antibodies in fecal water. Together, these studies demonstrate that antibodies to Z-DNA occur commonly in normal immunity and may arise as a response to Z-DNA of bacterial origin.
摘要：
DNA抗体是一组不同的抗体，可以结合DNA上的位点，显示各种构象的聚合物大分子。在之前的研究中,我们表明，正常健康受试者的血清（NHS）含有IgG抗体Z-DNA，左旋螺旋，有拉链-拉链骨架。最近的研究表明，细菌生物膜中存在Z-DNA，提示这种构象的来源来诱导反应。为了进一步表征Z-DNA的抗体，我们使用溴化poly(dGdC)作为Z-DNA来源的ELISA测定法,并测定了这些抗体的同种型及其结合特性.这些研究的结果表明NHS血清含有IgM和IgA以及IgG抗Z-DNA抗体。如缔合和解离测定中离子强度的影响所示，抗Z-DNA抗体主要通过静电相互作用结合;这种类型的结合不同于通过非离子相互作用结合的来自免疫动物的诱导的抗Z-DNA抗体。此外，尿素导致NHS抗Z-DNA解离的摩尔浓度远低于诱导抗体的摩尔浓度。这些研究还显示了粪便水中的IgA抗Z-DNA抗体。一起,这些研究表明，Z-DNA抗体通常发生在正常免疫中，可能是对细菌来源的Z-DNA的反应。
