Scientists Nicole Sampson and Hui Chen of the State University of New York at Stony Brook have made a discovery that could lead to a new kind of contraceptive that would enable human eggs to keep sperm cells at a distance.
The new method would make an unfertilized egg act as if it had already been fertilized. When an egg is fertilized by a sperm cell, biochemical interactions between that egg and sperm cell spur the egg to form a protective outer coating that blocks out other surrounding sperm cells. By preventing sperm cells from interacting with the egg, this protective coating would effectively prevent fertilization.
Sampson and Chen are credited with identifying an egg receptor which interacts with a sperm protein called fertilin-beta during fertilization. So far, researchers have discovered three binding proteins within sperm cells, and believe that an egg cell receptor called alpha-6/beta-1 integrin may be the best focus for attempts to block fertilization.
University of Pennsylvania at Philadelphia researcher Richard Schultz disagrees, noting that the alpha-6/beta-1 integrin receptor is found on cells other than the egg, and argues that attempts to disrupt this receptor’s normal functioning could produce significant side effects. Schultz contends that sperm proteins would be a better target for researchers.
See New Scientist magazine for article profiling the prospects for new fertilization-blocking contraceptives.