"Epithelial and Neural cadherins are present in spermatozoa and oocytes and participate in fertilization-related events. Studies in human, murine and bovine models

VAZQUEZ LEVIN, M; MARIN BRIGGILER, CI; EDELSZTEIN, NY; VEIGA, FLORENCIA; CABALLERO, J; ARZONDO, MM; ROSSO, M; MATOS, ML; LAPYCKYJ, L; DEL POZO, M

Melbourne

Congreso; 10th International Congress of Andrology; 2013

International Society of Andrology

Epithelial(E-cad) and Neural(N-cad) cadherins are involved in Ca+2-dependent cell-cell    adhesion/signalling in somatic cells. Fertilization depends on Ca+2 and involves somatic cell and sperm-oocyte interactions, but participation of cadherins in these events has not been characterized. This study aimed to evaluate E-cad and N-cad expression in reproductive tissues and gametes and to evaluate their involvement in fertilization using human/murine/bovine models. E-cad was immunolocalized to the plasma membrane of sperm, cumulus cells and oocytes, and the 120 KDa mature protein was immunodetected in all cases. Its expression (mRNA/protein) was characterized in the oviduct, ovary and epididymis. In the three models, gamete preincubation with anti E-cad antibodies inhibited sperm-ZP (P<0.05) and sperm-oolemma (P<0.05) adhesion, as well as mouse and bovine in vitro fertilization (P<0.001). Moreover, E-cad antibodies inhibited bovine sperm interaction with epithelial oviductal cells (OEC) in culture (P<0.05) and sperm released from co-cultures showed E-cadherin redistribution, with the same localization found after in vitro capacitation under defined conditions. N-cad immunolocalized to the plasma membrane of sperm and oocytes and the 135 KDa moiety was immunodetected in these cells; its expression in the male gonad was also verified (mRNA/protein). A high proportion of acrosome-reacted spermatozoa depicted a specific strong N-cad signal in the equatorial segment, and anti N-cad antibodies impaired sperm-oolemma interaction (P<0.05). We have characterized the expression of E-cad and N-cad in the male/female reproductive tract and gametes in human/mouse/bovine models and have demonstrated the ability of specific antibodies to block sperm-OEC and sperm-oocyte interactions, suggesting their involvement in fertilization-related events.