Jung F, Neuer G, Bautz F A
University of Heidelberg, Germany.
Arthritis Rheum. 1997 Oct;40(10):1803-9. doi: 10.1002/art.1780401012.
To extend our work on the mapping of B cell epitopes on nucleosomal high mobility group (HMG) proteins in the sera of patients with juvenile rheumatoid arthritis (JRA).
Seventy-seven pauciarticular-onset JRA serum samples from antinuclear antibody (ANA)-positive patients and 42 polyarticular-onset JRA patient sera found to react with HMG-2 by immunoblotting were used in this study. To identify B cell epitopes on HMG-2, recombinant HMG-2 protein fragments were used in enzyme-linked immunosorbent assay (ELISA) and in competition ELISA experiments with a set of overlapping synthetic peptides. Fine epitope mapping was achieved by oligopeptide synthesis, followed by immunoblotting.
Pauciarticular, but not polyarticular, JRA patient sera were found to recognize a lysine-rich major epitope (KKGKKKDP), which is located in the linker region of the HMG box domains of the HMG-2 nonhistone chromosomal protein. No significant immunoreactions were observed in sera from ANA-negative JRA patients and in sera from children with nonrheumatic diseases, indicating that this epitope seems to be specific for pauciarticular-onset JRA.
In addition to our previous finding that JRA sera will react with a defined epitope on HMG-17, pauciarticular JRA patient sera were also found to recognize a defined epitope on the HMG-2 protein, thus suggesting the importance of this epitope in the etiology of JRA.
扩展我们关于幼年类风湿关节炎（JRA）患者血清中核小体高迁移率族（HMG）蛋白上B细胞表位图谱的研究工作。
本研究使用了77份来自抗核抗体（ANA）阳性的少关节起病型JRA患者血清样本以及42份经免疫印迹法检测发现与HMG - 2发生反应的多关节起病型JRA患者血清。为了鉴定HMG - 2上的B细胞表位，将重组HMG - 2蛋白片段用于酶联免疫吸附测定（ELISA）以及与一组重叠合成肽进行竞争ELISA实验。通过寡肽合成，随后进行免疫印迹实现精细表位图谱绘制。
发现少关节起病型而非多关节起病型JRA患者血清能够识别一个富含赖氨酸的主要表位（KKGKKKDP），该表位位于HMG - 2非组蛋白染色体蛋白的HMG盒结构域的连接区。在ANA阴性的JRA患者血清以及非风湿性疾病儿童的血清中未观察到明显的免疫反应，表明该表位似乎对少关节起病型JRA具有特异性。
除了我们之前发现JRA血清会与HMG - 17上的一个特定表位发生反应外，还发现少关节起病型JRA患者血清也能识别HMG - 2蛋白上的一个特定表位，因此提示该表位在JRA病因学中的重要性。
