Ferro V A, Stimson W H
University of Strathclyde, Department of Immunology, Glasgow, Scotland.
Am J Reprod Immunol. 1998 Sep;40(3):187-97. doi: 10.1111/j.1600-0897.1998.tb00412.x.
Hormone immunoneutralization is hampered by immunologic cross-reactivity caused by close-sequence homology between related molecules. One solution is to use smaller fragments to induce antibodies of greater specificity.
A number of peptides selected from beta-follicle-stimulating hormone (FSH) were conjugated to tetanus toxoid and were used to immunize female rats. The antisera were examined for FSH cross-reactivity by immunoassays and in an in vitro bioassay.
In the immunoassays, the antisera did not react with FSH but did react with their respective peptides. In the bioassay, sera from VYKDPARPC- and CDSLYTYP-immunized animals inhibited FSH-receptor interaction by 73% and 68%, respectively. These animals also showed reduced estradiol levels. Sequences were synthesized around VYKDPARPC and were tested on a FSH-receptor-bearing Chinese hamster ovary cell line. LVYKDPARPC, VYKDPARPC, YKDPARPIC, CLVYKDPARP, and LVYKDPARP inhibited FSH-receptor interaction by greater than 50%. In female mice, TRDLVYKDPARPKI and LVYKDPARP disrupted estrous cycling in all animals; LVYKDPARPC and CLVYKDPARP disrupted cycling in three of five animals, whereas VYKDPARPC disrupted cycling in one of four animals.
Peptides from two areas of beta-FSH (VYKDPARP and DSLYTYP) were shown to raise FSH-neutralizing antibodies, which were able to suppress estradiol levels. An additional leucine residue to VYKDPARP greatly enhanced the peptide's ability to inhibit FSH-receptor binding and caused fertility disruption in vivo.
相关分子之间紧密的序列同源性所导致的免疫交叉反应阻碍了激素免疫中和作用。一种解决方法是使用更小的片段来诱导具有更高特异性的抗体。
从β-促卵泡激素（FSH）中选取的一些肽与破伤风类毒素偶联，并用于免疫雌性大鼠。通过免疫测定和体外生物测定来检测抗血清的FSH交叉反应性。
在免疫测定中，抗血清不与FSH反应，但与各自的肽发生反应。在生物测定中，用VYKDPARPC和CDSLYTYP免疫的动物血清分别抑制FSH受体相互作用73%和68%。这些动物的雌二醇水平也降低。围绕VYKDPARPC合成序列，并在表达FSH受体的中国仓鼠卵巢细胞系上进行测试。LVYKDPARPC、VYKDPARPC、YKDPARPIC、CLVYKDPARP和LVYKDPARP抑制FSH受体相互作用超过50%。在雌性小鼠中，TRDLVYKDPARPKI和LVYKDPARP使所有动物的发情周期紊乱；LVYKDPARPC和CLVYKDPARP使五只动物中的三只发情周期紊乱，而VYKDPARPC使四只动物中的一只发情周期紊乱。
来自β-FSH两个区域（VYKDPARP和DSLYTYP）的肽可产生FSH中和抗体，这些抗体能够抑制雌二醇水平。在VYKDPARP上额外添加一个亮氨酸残基极大地增强了该肽抑制FSH受体结合的能力，并在体内导致生育力紊乱。
