title: Prior immunity to a carrier enhances antibody responses to hCG in recipients of an hCG-carrier conjugate vaccine.
abstract: Pre-sensitization with carrier often leads to epitopic suppression of subsequent anti-hapten antibody responses. To ascertain whether epitopic suppression occurs in humans, we examined the effect of pre-existing anti-carrier immunity on antibody responses to hCG in volunteers of a clinical trial of an hCG-based conjugate birth-control vaccine. When we studied the correlation between pre-vaccination anti-carrier immunity and post-vaccination anti-hCG responses, we found that prior immunity to the carriers did not lead to epitopic suppression of anti-hCG responses. On the contrary, it was found that prior immunity to TT, one of the two carriers used in this vaccine, led to enhancement of anti-hCG responses. Our data indicates that prior immunity to the carriers may not be detrimental to the performance of conjugate vaccines, and may actually be beneficial in some cases.
authors.affiliation: National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, India. infonccs@giaspn01.vsnl.net.in
authors.forename: S
authors.initials: S
authors.lastname: Shah
authors.forename: R
authors.initials: R
authors.lastname: Raghupathy
authors.forename: O
authors.initials: O
authors.lastname: Singh
authors.forename: G P
authors.initials: GP
authors.lastname: Talwar
authors.forename: A
authors.initials: A
authors.lastname: Sodhi
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000096:biosynthesis / Q000097:blood; D002352:Carrier Proteins / Q000276:immunology*; D006063:Chorionic Gonadotropin / Q000276:immunology*; D003269:Contraception, Immunologic / Q000379:methods; D004168:Diphtheria Toxoid / Q000276:immunology; D005260:Female; D006801:Humans; D007115:Immunization Schedule; D007986:Luteinizing Hormone / Q000276:immunology; D013745:Tetanus Toxoid / Q000276:immunology; D018074:Vaccines, Conjugate / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D002352:Carrier Proteins; D006063:Chorionic Gonadotropin; D004168:Diphtheria Toxoid; D013745:Tetanus Toxoid; D018074:Vaccines, Conjugate; D007986:Luteinizing Hormone