Kawase Osamu, Jimbo Mitsuru
Department of Biology, Premedical Sciences, Dokkyo Medical University, Mibu-machi, Shimotsuga-gun, Tochigi 321-0293, Japan.
Department of Marine Biosciences, School of Marine Biosciences, Kitasato University, Kitasato, Sagamihara, Kanagawa 252-0373, Japan.
J Vet Med Sci. 2018 May 18;80(5):802-809. doi: 10.1292/jvms.17-0660. Epub 2018 Mar 16.
Antisperm antibodies potentially inhibit sperm functions causing the sterility in humans and experimentally treated animals. However, there is no information about antisperm antibodies emerging spontaneously in wildlife. In this study, we searched for the sperm-reactive antibodies, spontaneously produced in wild sika deer (Cervus nippon), and identified the sperm antigens. We collected 529 fecal masses of sika deer in Japanese cities, from which we extracted the mucosal antibodies to test them for reactivities to deer sperm proteins by ELISA. Two of the extracts contained IgAs that were highly reactive to the sperm proteins. The molecular weights of the active IgAs, partially purified by DEAE-sephadex A-50, were estimated at more than 100 kDa, suggesting that the IgAs evaded drastic digestion in the gastrointestinal tract. Two-dimensional electrophoresis and immunoblotting detected three major antigens, and the following LC-MS/MS analysis identified them as alpha-enolase, phosphoglycerate kinase 2 and acrosin-binding protein. The antibodies were cross-reactive to a recombinant human acrosin-binding protein. To our knowledge, this is the first research to find that the sperm-reactive antibodies are produced spontaneously in wildlife and they recognize a common antigen found in humans.
抗精子抗体可能会抑制精子功能，导致人类和实验处理动物的不育。然而，关于野生动物自发产生抗精子抗体的情况尚无相关信息。在本研究中，我们搜寻了野生梅花鹿（Cervus nippon）自发产生的精子反应性抗体，并鉴定了精子抗原。我们在日本城市收集了529份梅花鹿粪便样本，从中提取黏膜抗体，通过酶联免疫吸附测定（ELISA）检测其对鹿精子蛋白的反应性。其中两份提取物含有对精子蛋白具有高反应性的免疫球蛋白A（IgA）。经二乙氨基乙基葡聚糖A-50（DEAE-sephadex A-50）部分纯化后的活性IgA分子量估计超过100千道尔顿（kDa），这表明这些IgA在胃肠道中未被剧烈消化。二维电泳和免疫印迹检测到三种主要抗原，随后的液相色谱-串联质谱（LC-MS/MS）分析将它们鉴定为α-烯醇化酶、磷酸甘油酸激酶2和顶体蛋白结合蛋白。这些抗体与重组人顶体蛋白结合蛋白具有交叉反应性。据我们所知，这是首次发现野生动物会自发产生精子反应性抗体，且这些抗体识别出一种在人类中也存在的共同抗原的研究。
