Ara J, Ali A, Ali R
Department of Biochemistry, Faculty of Medicine, A. M. U. Aligarh, India.
Immunol Invest. 1992 Oct;21(6):553-63. doi: 10.3109/08820139209069390.
Hydroxyl radical, a prominent entity of reactive oxygen species, is known to modify cellular DNA and has been implicated in several human diseases. In the present studies, the radical was generated by exposure of hydrogen peroxide to 254 nm light in the presence of native calf thymus DNA. Single strand breaks, decrease in Tm and modification of adenine and thymine were some of the modifications observed in nDNA. Antibodies induced in experimental animals against the modified DNA were immunogen specific. These antibodies also recognize native B-conformation. It was observed that naturally occurring anti-native DNA autoantibodies from SLE sera recognize modified DNA in direct binding and competition ELISA. Gel retardation assay reiterated the formation of immune complexes between induced antibodies and DNA fragments of around 300 bp (B-conformation). The possible significance of these findings in the etiology of SLE has been discussed.
羟基自由基是活性氧物种的一个重要实体，已知其会修饰细胞DNA，并与多种人类疾病有关。在本研究中，通过在天然小牛胸腺DNA存在的情况下，将过氧化氢暴露于254 nm光来产生该自由基。单链断裂、熔解温度降低以及腺嘌呤和胸腺嘧啶的修饰是在天然DNA中观察到的一些修饰。在实验动物中诱导产生的针对修饰DNA的抗体具有免疫原特异性。这些抗体也识别天然B构象。据观察，来自系统性红斑狼疮（SLE）血清的天然存在的抗天然DNA自身抗体在直接结合和竞争酶联免疫吸附测定（ELISA）中识别修饰DNA。凝胶阻滞分析再次证实诱导抗体与约300 bp（B构象）的DNA片段之间形成了免疫复合物。已讨论了这些发现对SLE病因学的可能意义。
