Suzuki Nobuyuki, Wakasugi Masahiko, Nakaya Seigo, Kokubo Naomi, Sato Masami, Kajiyama Hirofumi, Takahashi Ryoki, Hirata Haruhisa, Ezure Yohji, Fukuda Yoshihiro, Shimoyama Takashi
Sagami Research Laboratories, Wakamoto Pharmaceutical Co., Ltd., Ohimachi, Ashigarakami-gun, Kanagawa 258-0018, Japan.
Clin Diagn Lab Immunol. 2002 Jul;9(4):784-8. doi: 10.1128/cdli.9.4.784-788.2002.
Recently, we reported the production of three new monoclonal antibodies with high specificity for a Helicobacter pylori antigen suitable for diagnosis of H. pylori infection. The aim of the present study was to identify the antigen recognized by these monoclonal antibodies concerning both H. pylori and the feces of human subjects infected with H. pylori. The cellular antigen was purified from an H. pylori cell extract by immunoaffinity column chromatography with the monoclonal antibody as a ligand. The amino-terminal amino acid sequences (eight residues) of the purified antigen and H. pylori catalase were the same. The molecular weights of native and subunit, specific catalase activity, and UV and visible spectra of the purified antigen were in good agreement with those of H. pylori catalase. The human fecal antigens were purified from two fecal samples of two H. pylori-positive subjects by ammonium sulfate precipitation, CM-Sephadex C(50) chromatography, and the same immunoaffinity chromatography used for the H. pylori cellular antigen. The fecal antigens had catalase activity. The amino-terminal amino acid sequences (five residues) of the human fecal antigen and H. pylori catalase were the same. The monoclonal antibodies reacted with the native cellular antigen, but did not react with the denatured antigen, human catalase, and bovine catalase. The results show that the target antigen of the monoclonal antibodies is native H. pylori catalase and that the monoclonal antibodies are able to specifically detect the antigen, which exists in an intact form, retaining the catalase activity in human feces.
最近，我们报道了三种新的单克隆抗体的制备，它们对一种适合用于诊断幽门螺杆菌感染的幽门螺杆菌抗原具有高特异性。本研究的目的是确定这些单克隆抗体所识别的与幽门螺杆菌以及感染幽门螺杆菌的人类受试者粪便相关的抗原。通过以单克隆抗体为配体的免疫亲和柱色谱法从幽门螺杆菌细胞提取物中纯化细胞抗原。纯化抗原的氨基末端氨基酸序列（八个残基）与幽门螺杆菌过氧化氢酶的相同。纯化抗原的天然和亚基分子量、比过氧化氢酶活性以及紫外和可见光谱与幽门螺杆菌过氧化氢酶的一致。通过硫酸铵沉淀、CM-葡聚糖凝胶C(50)色谱法以及用于幽门螺杆菌细胞抗原的相同免疫亲和柱色谱法从两名幽门螺杆菌阳性受试者的两份粪便样本中纯化人粪便抗原。粪便抗原具有过氧化氢酶活性。人粪便抗原的氨基末端氨基酸序列（五个残基）与幽门螺杆菌过氧化氢酶的相同。单克隆抗体与天然细胞抗原反应，但不与变性抗原、人过氧化氢酶和牛过氧化氢酶反应。结果表明，单克隆抗体的靶抗原是天然幽门螺杆菌过氧化氢酶，并且单克隆抗体能够特异性检测以完整形式存在、在人粪便中保留过氧化氢酶活性的抗原。
