Premium
Immunocontraception in mice using repeated, multi‐antigen peptides: immunization with purified recombinant antigens
Author(s) -
Hardy Christopher M.,
Beaton Sandra,
Hinds Lynette A.
Publication year - 2008
Publication title -
molecular reproduction and development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.745
H-Index - 105
eISSN - 1098-2795
pISSN - 1040-452X
DOI - 10.1002/mrd.20745
Subject(s) - biology , antigen , recombinant dna , epitope , antibody , peptide , microbiology and biotechnology , maltose binding protein , escherichia coli , immunology , genetics , biochemistry , gene , fusion protein
Two immunocontraceptive antigens (AgE and AgF) were constructed that included different combinations of highly species‐specific peptides from the mouse reproductive antigens SP56, ZP3, ZP2, and ZP1 in the form of multi‐antigen peptides (MAPs). Both AgE and AgF contained three tandem repeats each of ZP2 and ZP3 peptide epitopes and a single copy of a ZP1 peptide sequence all of which had previously been demonstrated to individually have immunodominant or contraceptive effects. In addition, AgF contained a single contraceptive peptide derived from SP56, the putative ZP3 receptor protein on sperm. The antigens were expressed and affinity purified as recombinant repeated multi‐antigen (polyepitope) peptides using an Escherichia coli maltose binding protein (MBP) expression system. Female BALB/c mice actively immunized with these antigens in Freund's adjuvants produced variable serum antibody responses to the component peptides. Fertility rates for animals immunized with AgE (40%) and AgF (20%) were significantly reduced compared to MBP immunized mice (90%), but the reduction in fertility did not correlate with peptide‐specific serum antibody levels. Ovaries from all immunized mice appeared histologically normal with no evidence of oophoritis. These results demonstrate that high levels of immunocontraception can be achieved in mice, without apparent side‐effects, using species‐specific immunogens that include repeated peptides from proteins involved in fertilization. Mol. Reprod. Dev. 75: 126–135, 2008. © 2007 Wiley‐Liss, Inc.