Immunogenicity Study of Plasmid DNA Encoding Mouse Cysteine‐Rich Secretory Protein‐1 (mCRISP1) as a Contraceptive Vaccine

Abstract

Problem To examine the immunocontraceptive properties of the plasmid pcDNA‐mCRISP1 and compare them to the corresponding recombinant mCRISP1 (r‐mCRISP1). Method of study RT‐PCR and indirect immunofluorescence were performed to observe the mCRISP1 protein expression in COS‐7 cells. Three groups of mice received three injections of r‐mCRISP1, pcDNA‐mCRISP1 or pcDNA vector, respectively. ELISA and Western blot were used to examine the immune responses and immunoreactivity of antisera. Sperm‐egg penetration assay was performed to examine the effect of anti‐mCRISP1 antibodies in vitro fertilization of mouse oocytes. Fertility and mean litter size were analysed by natural mating. Histological analysis was carried out to look for potential immunopathologic effects of the antibodies. Results COS‐7 cells transfected with pcDNA‐mCRISP1 present the expression of mCRISP1. Both r‐mCRISP1 and pcDNA‐mCRISP1 raised an immune response against r‐mCRISP1 protein and native CRISP1 in mouse sperm. The titres of anti‐mCRISP1 antibodies from DNA immunized mice were significantly lower than that of r‐mCRISP1 immunized mice, but it lasted relatively longer. Male and female pcDNA‐mCRISP1 injected animals presented a statistically significant reduction in their fertility with no signs of immunopathologic effects. Conclusion These studies demonstrated the feasibility of generating an immune response to mCRISP1 protein by DNA vaccine and pcDNA‐mCRISP1 plasmid causing significant anti‐fertility potential.

Effect of immunization against prostate- and testis-expressed (PATE) proteins on sperm function and fecundity in the rat

“…This strategy is based on the induction of antibodies against epididymal or testicular proteins so that they do not associate with the sperm surface or mask them to prevent interaction with other proteins for maturation. Examples include: antisperm antibodies (Vazquez-Levin (Luo et al, 2012), eppin (O'Rand et al, 2006), Bin1b (Li et al, 2001), FA-1 (Naz and Zhu, 1998), LDH-C4 (O'Hern et al, 1997), P10G (O'Rand et al, 1993, A9D (Lea et al, 1998), SP56 (Hardy and Mobbs, 1999), 80 kDa HSA (Khobarekar et al, 2008), YLP12 (Naz and Chauhan, 2002), zona pellucida proteins (Eade et al, 2009), and Izumo (Naz, 2008;Wang et al, 2009). We previously demonstrated that the rat PATE proteins are localized on the sperm surface and are predicted to play a role in sperm function (Rajesh and Yenugu, 2012).…”

“…Sperm maturation is facilitated by a number of proteins secreted by the epididymal epithelial cells into the luminal fluid, which then bind on to the sperm surface (Ducheux et al, 2003). Defensins (Yenugu et al, 2004(Yenugu et al, , 2006Travis et al, 2000), members of the sperm-associated antigen 11 family (Hamil et al, 2000), lysozymes Mandal et al, 2003), lipocalins (Hamil et al, 2003), cathelicidins, protease inhibitors Blankenvoorde et al, 1998;Hiemstra et al, 1996), inhibitors of complement lysis (Collard and Griswold, 1987;Griswold et al, 1986), the cysteine-rich proteins such as CRISPs (Jalkanen et al, 2005;Luo et al, 2012), and members of the prostate-and testis-expressed (PATE) family (Bera et al, 2002;Soler-Garcia et al, 2005;Levitin et al, 2008;Turunen et al, 2011) are some examples of a wide range of proteins that bind to the sperm surface . Further, a variety of factors secreted by the seminal vesicles and prostate also aid in the formation of functional http://dx.doi.org/10.1016/j.jri.2015.02.009 0165-0378/© 2015 Elsevier Ireland Ltd. All rights reserved.…”

The preparation and application of N-terminal 57 amino acid protein of the follicle-stimulating hormone receptor as a candidate male contraceptive vaccine

“…Development of contraceptive vaccines for males is of great importance for global population control. Up to the present, many efforts have been put into developing male contraceptive vaccines 4725. Although the hormonal approach to male contraception has made significant progress in the last decade, it has encountered bottlenecks because of the non-ignorable side effects 262728.…”

“…Data from animal experiments and some clinical trials provide several good male contraception targets 5678. Among these, follicle-stimulating hormone (FSH) has been paid more attention for its importance in quantitatively and qualitatively normal spermatogenesis and spermatogonial maturation 910.…”

The Immunogenicity of CRISP1 Plasmid‐Based Contraceptive Vaccine can be Improved When Using Chitosan Nanoparticles as the Carrier

“…In the previous study, our group constructed a genetic immunocontraceptive vaccine‐based mouse CRISP1 (mCRISP1), which then be demonstrated can successfully elicit anti‐mCRISP1 antibodies in both male and female BALB/c mice and the antibodies thus generated recognized native CRISP1 protein in mouse sperm . However, the antifertility effect of the mCRISP1 DNA vaccine on mice is not satisfactory.…”