Identification of human sperm proteins involved in the interaction with homologous zona pellucida.
OBJECTIVE
To identify human sperm proteins involved in homologous zona pellucida (ZP) interaction.


METHODS
Prospective study.


METHODS
Basic research laboratory.


METHODS
Semen samples from normozoospermic donors, tissue sections from surgical pieces, and ZP from nonfertilized oocytes.


METHODS
Antibodies for sperm proteins (HSE; high salt extract) were developed (anti-HSE) and partially characterized. Participation of sperm proteins on ZP-interaction was tested with the hemizona assay (HZA). Antigens were immunolocalized in sperm and tissues.


METHODS
Sperm and tissue immunostaining; Western blotting; and number of sperm bound to the ZP.


RESULTS
Anti-HSE antibodies recognized several polypeptides in HSE (9 to 200 kd). Specific antibodies for 49 and 66 kd proteins (p49, p66) were obtained. Both (anti-p49 and anti-p66) stained the head of ejaculated and capacitated sperm. In the HZA, sperm preincubation with a mixture of anti-p49 and anti-p66 (100 micro g/mL) resulted in a decrease in the number of spermatozoa bound to the ZP. Presence of p66 (10 micro g/mL) inhibited sperm-ZP interaction. In contrast, p49 did not alter sperm binding to the ZP. Immunohistochemical analysis showed that p66 is present in the epididymis. No staining was observed in testicular sections.


CONCLUSIONS
We found that p66 is an epididymal protein that participates in human sperm interaction with homologous ZP.
Lasserre
Andrea
A
Instituto de Biología y Medicina Experimental, CONICET-UBA, Buenos Aires, Argentina.
González-Echeverría
Fernanda
F
Moules
Carolina
C
Tezón
Jorge G
JG
Miranda
Patricia V
PV
Vazquez-Levin
Mónica H
MH
D015153:Blotting, Western; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011506:Proteins / Q000302:isolation & purification* / Q000502:physiology; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000737:chemistry*; D015044:Zona Pellucida / Q000502:physiology*
D011506:Proteins