In 1979 one of the first Zweig Fund grants was awarded to Dr. Antczak, who had just begun his faculty appointment at Cornell. That project, on maternal immune recognition of pregnancy, began a 35 year collaboration and friendship between Dr. Antczak and Dr. W. R. Allen, whose background came from directing the British Thoroughbred Breeders' Association Equine Fertility Unit in Cambridge, England.
In the following years Antczak and Allen and their students and staff discovered how the cells of the placenta, particularly the endometrial cups, control the expression of their histocompatibility genes to avoid destruction by the mother's immune system. They also learned how the mother's immune system is regulated during pregnancy to ensure that deleterious anti-fetal immune reactions are not produced. Finally, the group developed and characterized unique models of pregnancy failure using embryo transfer between horses and donkeys and the use of sterile hybrid mules as embryo recipients. Taken together, these studies have advanced our understanding of how mother, fetus, and placenta communicate and compromise during pregnancy to bring about the miracle of birth.