Department of Biosciences, Integral University, Lucknow 226026, India; IIRC-1 Laboratory of Glycation Biology and Metabolic Disorders, Integral University, Lucknow 26026, India.
Department of Botany & Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
Int J Biol Macromol. 2019 Feb 15;123:427-435. doi: 10.1016/j.ijbiomac.2018.11.063. Epub 2018 Nov 13.
Non-enzymatic glycation occurs rapidly which ultimately leads to the formation of advanced glycation endproducts (AGEs). These AGEs have shown to associated with the development of many diseases such as diabetes-mellitus. This study is focused on immunological characterization of glycated-Hb induced by d-ribose. Here, we analysed the immunogenicity of glycated-Hb by direct binding and competitive inhibition ELISA. Direct binding ELISA confirmed that glycated-Hb was highly immunogenic and induced high titre antibodies as compared to native-Hb. The antigen binding specificity and cross reactivity of these antibodies were also screened by competitive inhibition ELISA. The IgG from rabbit sera showed enhanced binding of glycated-Hb than native-Hb. Thus, it is possible that alterations in Hb induced by d-ribose could have generated highly immunogenic neoepitopes. Moreover, induced antibodies were also found to cross-react with other modified/native proteins. On the basis of the results of this study, we presume that this type of structural perturbations in Hb in vivo by d-ribose might take place in untreated diabetic condition that could induce such type of immunogenic auto-antibodies. Furthermore, increased level of these auto-antibodies could serve as a biomarker in diabetes and its progression.
非酶糖基化反应迅速,最终导致晚期糖基化终产物(AGEs)的形成。这些 AGEs 已被证明与许多疾病的发展有关,如糖尿病。本研究专注于 d-核糖诱导的糖化 Hb 的免疫学特性。在这里,我们通过直接结合和竞争抑制 ELISA 分析了糖化 Hb 的免疫原性。直接结合 ELISA 证实,与天然 Hb 相比,糖化 Hb 具有高度的免疫原性,并诱导产生高滴度的抗体。这些抗体的抗原结合特异性和交叉反应性也通过竞争抑制 ELISA 进行了筛选。兔血清中的 IgG 显示出对糖化 Hb 的结合增强,而对天然 Hb 的结合则较弱。因此,d-核糖引起的 Hb 变化可能产生了高度免疫原性的新表位。此外,诱导的抗体也被发现与其他修饰/天然蛋白发生交叉反应。基于这项研究的结果,我们推测 d-核糖在未经治疗的糖尿病状态下可能会在体内引起 Hb 的这种结构改变,从而诱导这种类型的免疫原性自身抗体。此外,这些自身抗体水平的升高可以作为糖尿病及其进展的生物标志物。