Beijing Institute of Biotechnology, 20 Dongdajie Street, Fengtai District, Beijing 100071, PR China.
Vaccine. 2010 Jul 19;28(32):5220-7. doi: 10.1016/j.vaccine.2010.05.067. Epub 2010 Jun 9.
To identify linear B-cell epitopes of urease B (UreB), a series of 19 partially overlapping fragments of the UreB gene were expressed. Three MAbs against UreB of Helicobacter pylori (H. pylori), A1H10, A3C10, and B3D9, were tested for their reactivity to the truncated proteins by Western blot and enzyme-linked immunosorbent assay (ELISA). Three linear B-cell epitopes were identified covering a stretch of 15 amino acid (aa) residues and localized in the aa regions 158-172, 181-195, and 349-363 of UreB. ELISA also showed that the three synthetic peptides containing epitope sequences (UP32: GGGTGPADGTNATTI, UP35: WMLRAAEEYSMNLGF, and UP38: TLHDMGIFSITSSDS) were recognized by the corresponding MAbs and H. pylori positive sera from H. pylori infected patients. Mice immunized with glutathione S-transferase (GST) fusion peptides showed that epitope-specific antibodies were capable of inhibiting urease enzymatic activity. These results should be useful in clinical applications and highlight the potential importance of these epitopes as the targets for development of epitope-based vaccines against H. pylori.
为了鉴定脲酶 B (UreB) 的线性 B 细胞表位，我们表达了 UreB 基因的一系列 19 个部分重叠的片段。我们用 Western blot 和酶联免疫吸附试验（ELISA）检测了针对幽门螺杆菌（H. pylori）UreB 的三种单克隆抗体（MAb）A1H10、A3C10 和 B3D9 对截断蛋白的反应性。鉴定出三个线性 B 细胞表位，覆盖 15 个氨基酸（aa）残基，定位于 UreB 的 aa 区域 158-172、181-195 和 349-363。ELISA 还显示，三个含有表位序列的合成肽（UP32：GGGTGPADGTNATTI、UP35：WMLRAAEEYSMNLGF 和 UP38：TLHDMGIFSITSSDS）被相应的 MAb 和来自 H. pylori 感染患者的 H. pylori 阳性血清识别。用谷胱甘肽 S-转移酶（GST）融合肽免疫的小鼠表明，表位特异性抗体能够抑制脲酶的酶活性。这些结果在临床应用中应该是有用的，并突出了这些表位作为开发基于表位的 H. pylori 疫苗的潜在重要性。
