Characterization of anti oLH beta-antibodies acting as contraceptives in rhesus monkeys. I. In vitro binding properties.
Female monkeys actively immunized with oLHbeta are infertile when circulation antibody titers become sufficiently high to bind 30% of an iodinated hCG standard. We report here the extensive characterization of the oLHbeta antibodies. Their binding affinity and capacity for human and rhesus gonadotropins were determined. The affinity was high (Ka - 10(9) M-1) and was similar for high, medium and low titer antisera. In contrast, the binding capacity for hCG correlated well with antibody titers (n = 18, r = 0.888, P less than 0.001) and ranged from 0.09 to 8.3 x 10(-7)M. Column chromatographic analysis showed that anti-oLHbeta was mostly IgG. A temporal increase of affinity ('maturation') after booster was absent in the majority of monkeys. Cross-reaction between hCG and hLH as well as rhCG and rhLH was high. The latter, however, did not interfere with regular cycles and ovulation, suggesting that oLHbeta may be a useful antigen for human contraception.
D000818:Animals; D000915:Antibody Affinity; D000936:Antigen-Antibody Complex; D000937:Antigen-Antibody Reactions; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D011232:Chemical Precipitation; D006063:Chorionic Gonadotropin / Q000378:metabolism; D003271:Contraceptive Agents, Female / Q000378:metabolism*; D005260:Female; D006041:Goats; D006801:Humans; D007518:Isoantibodies / Q000145:classification; D007986:Luteinizing Hormone / Q000276:immunology* / Q000378:metabolism; D008253:Macaca mulatta; D011247:Pregnancy; D011956:Receptors, Cell Surface; D011974:Receptors, LH; D013997:Time Factors
D000936:Antigen-Antibody Complex; D006063:Chorionic Gonadotropin; D003271:Contraceptive Agents, Female; D007518:Isoantibodies; D011956:Receptors, Cell Surface; D011974:Receptors, LH; D007986:Luteinizing Hormone