Carron C P, Mathias A, Saling P M
Department of Obstetrics and Gynecology, Duke University Medical Center, Durham, North Carolina 27710.
Biol Reprod. 1989 Jul;41(1):153-62. doi: 10.1095/biolreprod41.1.153.
Antibodies to components of sperm can interfere with sperm function and prevent fertilization by blocking specific steps of gamete interaction. It can be proposed that anti-idiotype antibodies (anti-Ids) that recognize determinants located close to or within the antigen-binding site of an anti-sperm antibody could block antibody binding to sperm antigen and antibody-mediated inhibition of fertilization. To test this hypothesis, rabbit polyclonal antibodies to idiotypic determinants of the monoclonal anti-sperm antibody M42.15 were developed and characterized. Previous studies demonstrated that M42.15 monoclonal antibody (mAb) inhibits fertilization in vitro and in vivo by inhibiting sperm-zona pellucida interaction. Anti-idiotype antibodies to M42.15 mAb (anti-Id M42) were isolated by affinity chromatography on immobilized M42.15 mAb. Binding specificity of anti-Id M42.15 was demonstrated in a solid-phase radioimmune binding assay and by specific immunoprecipitation of soluble M42.15 mAb. Anti-Id M42 competitively inhibited M42.15 mAb, but not P220.2 mAb, binding to mouse sperm, confirming that the anti-Id preparation contained antibodies directed against idiotopes within or adjacent to the antigen-binding site of the mAb. At equimolar concentrations, anti-Id M42 inhibited binding of 125I-labeled M42.15 mAb to sperm by greater than 80%. These results showed that anti-Id M42 efficiently blocked antibody binding to sperm and suggested that anti-Id M42 could be used to neutralize the anti-fertility activity of the M42.15 mAb. When tested in in vitro fertilization assays, anti-Id M42, but not rabbit immunoglobulin, prevented M42.15 mAb-induced inhibition of fertilization. Together, these results show that the inhibitory activity of anti-sperm antibodies capable of interfering with gamete interaction can be neutralized by anti-Id that recognize determinants close to the antigen-combining site of the anti-sperm antibody.
针对精子成分的抗体可干扰精子功能，并通过阻断配子相互作用的特定步骤来阻止受精。可以提出，识别位于抗精子抗体抗原结合位点附近或内部的决定簇的抗独特型抗体（抗Id）可阻断抗体与精子抗原的结合以及抗体介导的受精抑制。为了验证这一假设，制备并鉴定了针对单克隆抗精子抗体M42.15独特型决定簇的兔多克隆抗体。先前的研究表明，M42.15单克隆抗体（mAb）通过抑制精子与透明带的相互作用在体外和体内抑制受精。通过在固定化M42.15 mAb上进行亲和层析分离出针对M42.15 mAb的抗独特型抗体（抗Id M42）。抗Id M42.15的结合特异性在固相放射免疫结合试验以及可溶性M42.15 mAb的特异性免疫沉淀中得到证实。抗Id M42竞争性抑制M42.15 mAb与小鼠精子的结合，但不抑制P220.2 mAb与小鼠精子的结合，这证实抗Id制剂包含针对mAb抗原结合位点内或附近独特位的抗体。在等摩尔浓度下，抗Id M42抑制125I标记的M42.15 mAb与精子的结合达80%以上。这些结果表明，抗Id M42有效地阻断了抗体与精子的结合，并提示抗Id M42可用于中和M42.15 mAb的抗生育活性。在体外受精试验中进行测试时，抗Id M42而非兔免疫球蛋白可阻止M42.15 mAb诱导的受精抑制。总之，这些结果表明，能够干扰配子相互作用的抗精子抗体的抑制活性可被识别抗精子抗体抗原结合位点附近决定簇的抗Id中和。
