Immunologic behavior of human cysteine-rich secretory protein 1 (hCRISP1) in primates: prospects for immunocontraception.
OBJECTIVE
To evaluate the immunologic behavior of human cysteine-rich secretory protein 1 (hCRISP1), a human sperm epididymal protein involved in fertilization, to establish its immunocontraceptive potential.


METHODS
In vivo study in a nonhuman primate model.


METHODS
Animal care facility of an academic research center.


METHODS
Adult (6- to 15-year-old) male and female cynomolgus macaques (Macaca fascicularis) distributed into three groups.


METHODS
Animals received four injections (intramuscularly) of recombinant hCRISP1, recombinant monkey CRISP1 (mkCRISP1), or maltose-binding protein (MBP). Blood and semen samples were obtained before and after immunization.


METHODS
Anti-hCRISP1 and anti-mkCRISP1 levels in sera and seminal plasma were evaluated by enzyme-linked immunosorbent assay (ELISA). The specificity of the immune response was evaluated by Western blot and binding of the antibodies to sperm by immunofluorescence.


RESULTS
Both hCRISP1 and mkCRISP1 raised an immune response that increased as a function of time and specifically recognized mkCRISP1 in sperm extracts. Sperm number, motility, and morphology were not affected by immunization. The presence of both specific antibodies in seminal plasma and a fluorescent labeling in sperm exposed only to second antibody indicated the ability of the anti-hCRISP1 antibodies both to enter into the male reproductive tract and to bind to the cells in vivo.


CONCLUSIONS
These results support the potential involvement of anti-hCRISP1 antibodies in human immunoinfertility and hCRISP1 as a likely candidate for immunocontraception.
Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina.
Diego A
DA
Ellerman
Débora J
DJ
Cohen
Mariana
M
Weigel Muñoz
Vanina G
VG
Da Ros
Juan I
JI
Ernesto
Ted L
TL
Tollner
Patricia S
PS
Cuasnicu
D000818:Animals; D003269:Contraception, Immunologic / Q000379:methods; D005260:Female; D006801:Humans; D008252:Macaca fascicularis / Q000276:immunology*; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology*; D013094:Spermatozoa / Q000276:immunology
C103538:CRISP1 protein, human; D008562:Membrane Glycoproteins