Millar S E, Chamow S M, Baur A W, Oliver C, Robey F, Dean J
Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD 20892.
Science. 1989 Nov 17;246(4932):935-8. doi: 10.1126/science.2479101.
The zona pellucida surrounding mouse oocytes is an extracellular matrix composed of three sulfated glycoproteins, ZP1, ZP2, and ZP3. It has been demonstrated that a monoclonal antibody to ZP3 injected into female mice inhibits fertilization by binding to the zona pellucida and blocking sperm penetration. A complementary DNA encoding ZP3 was randomly cleaved and 200- to 1000-base pair fragments were cloned into the expression vector lambda gt11. This epitope library was screened with the aforementioned contraceptive antibody, and the positive clones were used to map the seven-amino acid epitope recognized by the antibody. Female mice were immunized with a synthetic peptide containing this B cell epitope coupled to a carrier protein to provide helper T cell epitopes. The resultant circulating antibodies to ZP3 bound to the zona pellucida of immunized animals and produced long-lasting contraception. The lack of ovarian histopathology or cellular cytotoxicity among the immunized animals may be because of the absence of zona pellucida T cell epitopes in this vaccine.
围绕小鼠卵母细胞的透明带是一种由三种硫酸化糖蛋白ZP1、ZP2和ZP3组成的细胞外基质。已经证明，将针对ZP3的单克隆抗体注射到雌性小鼠体内，通过与透明带结合并阻止精子穿透来抑制受精。编码ZP3的互补DNA被随机切割，200至1000个碱基对的片段被克隆到表达载体λgt11中。用上述避孕抗体筛选该表位文库，阳性克隆用于定位该抗体识别的七氨基酸表位。用与载体蛋白偶联的含有该B细胞表位的合成肽免疫雌性小鼠，以提供辅助性T细胞表位。由此产生的针对ZP3的循环抗体与免疫动物的透明带结合，并产生长效避孕作用。免疫动物中缺乏卵巢组织病理学改变或细胞毒性可能是因为该疫苗中不存在透明带T细胞表位。
