Pisetsky D S, Gonzalez T C
Medical Research Service, Department of Veterans Affairs Medical Center, Division of Rheumatology, Allergy and Clinical Immunology, Duke University Medical Center, Durham, NC, USA.
Clin Exp Immunol. 1999 May;116(2):354-9. doi: 10.1046/j.1365-2249.1999.00875.x.
To elucidate antibody recognition of DNA in normal and aberrant immunity, the binding of sera of normal human subjects (NHS) and patients with SLE was tested with mammalian and bacterial DNA varying in size. Klebsiella pneumoniae (KP) and calf thymus (CT) single-stranded DNA (ssDNA) were investigated as model antigens using the restriction enzyme HinfI to generate fragments with the size range of 800-5000 base pairs. The influence of size on activity was assessed by ELISA by both titration of serum as well as coating antigen concentration. In both assay formats, SLE sera bound equivalently to intact CT and KP DNA, but had dramatically reduced reactivity to fragments of both antigens. In contrast, NHS bound similarly to intact KP DNA and its fragments but had low reactivity to CT DNA. These results suggest that SLE and NHS anti-DNA react with different antigenic determinants on DNA, as shown by cross-reactivity as well as size dependency in solid-phase assays.
为阐明正常免疫和异常免疫中抗体对DNA的识别情况，我们检测了正常人血清（NHS）和系统性红斑狼疮（SLE）患者血清与不同大小的哺乳动物和细菌DNA的结合情况。使用限制性内切酶HinfI将肺炎克雷伯菌（KP）和小牛胸腺（CT）单链DNA（ssDNA）作为模型抗原进行研究，以产生大小范围为800 - 5000个碱基对的片段。通过ELISA，通过血清滴定以及包被抗原浓度来评估大小对活性的影响。在两种检测形式中，SLE血清与完整的CT和KP DNA等效结合，但对两种抗原的片段反应性显著降低。相比之下，NHS与完整的KP DNA及其片段结合相似，但对CT DNA反应性较低。这些结果表明，如固相分析中的交叉反应性和大小依赖性所示，SLE和NHS抗DNA与DNA上不同的抗原决定簇发生反应。
