title: Immunogenic comparison for two different recombinant chimeric peptides (CP12 and CP22) containing one or two copies of three linear B cell epitopes from β-hCG subunit.
abstract: To develop a superior chimeric peptide (CP) vaccine of human chorionic gonadotropin (hCG), two CP antigens (named CP12 and CP22) encoding one or two copies of three linear B cell epitopes from the β-hCG subunit and six foreign T cell epitopes, including two promiscuous TCEs from hepatitis B surface antigen and tetanus toxoid, were constructed and biosynthesized. The hCG CP12 and CP22 of 21 or 23 kDa, respectively, were expressed in Escherichia coli at the level of ~1% of total cell proteins when inserted into thermo-inducible pBV221 expression vector. The purified CP12 and CP22 proteins with >95% relative homogeneity are immunogenic, and elicited antibodies against the β5, β9 and β8 BCEs of β-hCG in both rabbits and three different inbred strains of mice. A mouse uterine weight study in Balb/c mice demonstrated that the CP12 and CP22 antigens with an additional β5 neutralizing epitope enhanced the in vivo bio-neutralization capacity of the induced antibodies compared to the C-terminal immunogen of β-hCG. We propose that the biosynthesized CP22, possessing with two copies of three BCEs, represents a novel candidate antigen for an hCG contraceptive or tumor therapeutic vaccine.
authors.affiliation: Department of Reproductive Biology, Shanghai Institute of Planned Parenthood Research, 2140 Xie Tu Road, Shanghai 200032, PR China.
authors.forename: Ya-ping
authors.initials: YP
authors.lastname: He
authors.forename: Wan-xiang
authors.initials: WX
authors.lastname: Xu
authors.forename: Ai-zhen
authors.initials: AZ
authors.lastname: Hong
authors.forename: Mao-chuan
authors.initials: MC
authors.lastname: Liao
authors.forename: Chao-neng
authors.initials: CN
authors.lastname: Ji
authors.forename: Shao-hua
authors.initials: SH
authors.lastname: Gu
authors.forename: Jin-zhong
authors.initials: JZ
authors.lastname: Chen
authors.forename: Yi
authors.initials: Y
authors.lastname: Xie
mesh_terms: D000818:Animals; D015153:Blotting, Western; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D018985:Epitopes, B-Lymphocyte / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D004926:Escherichia coli; D005260:Female; D051379:Mice; D009929:Organ Size; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D012680:Sensitivity and Specificity; D013237:Stereoisomerism; D014599:Uterus / Q000378:metabolism; D022223:Vaccines, Subunit / Q000737:chemistry / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D014614:Vaccines, Synthetic / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human; D018985:Epitopes, B-Lymphocyte; D011993:Recombinant Fusion Proteins; D022223:Vaccines, Subunit; D014614:Vaccines, Synthetic