Treadwell E L, Müller U R, Volkman A
Department of Medicine, East Carolina University School of Medicine, Greenville 27858-4354.
J Immunol Methods. 1991 Sep 13;142(2):157-67. doi: 10.1016/0022-1759(91)90102-l.
Antibodies to Su antigen have been reported previously as a distinct antigen-antibody system associated with connective tissue diseases; most specifically systemic lupus erythematosus and undifferentiated connective tissue disease. The Su antigen was first identified by double immunodiffusion using calf thymus nuclear extract (CTNE) as a source for Su antigen. In this report, enhanced extraction of Su antigen was achieved using deoxyribonuclease I (DNase) for preparation of CTNE. Only the Sm antigen was found in comparable quantities in the DNase CTNE. Western immunoblotting and immunoprecipitation employing DNase CTNE and extracts of [35S]methionine-labeled HeLa cells respectively were used for further characterization and differentiation of the Su antigen. Sera from patients positive for Su antibodies by double immunodiffusion were found to react most specifically with antigen components in a molecular weight range of approximately 50-55 kDa. These methods should assist in further understanding the biochemical properties of the Su antigen.
抗Su抗原的抗体先前已有报道，它是一种与结缔组织疾病相关的独特抗原-抗体系统；最典型的是系统性红斑狼疮和未分化结缔组织病。Su抗原最初是通过使用小牛胸腺核提取物（CTNE）作为Su抗原来源的双向免疫扩散法鉴定出来的。在本报告中，使用脱氧核糖核酸酶I（DNase）制备CTNE实现了Su抗原的增强提取。在DNase CTNE中仅发现了等量的Sm抗原。分别采用DNase CTNE和[35S]甲硫氨酸标记的HeLa细胞提取物进行的Western免疫印迹和免疫沉淀，用于Su抗原的进一步表征和鉴别。通过双向免疫扩散检测Su抗体呈阳性的患者血清，被发现与分子量约为50-55 kDa范围内的抗原成分反应最为特异。这些方法应有助于进一步了解Su抗原的生化特性。
