Project 172320

In Canada about one in eight couples suffer from some form of infertility. Data obtained over the past twenty years revealed that approximately 30% of cases of infertility are found in the man alone, and another 20% involve abnormality found in both man and woman. Taken together, the male factor is at least partly responsible in about 50% of infertile couples. To date, reliable clinical assays for sperm fertilizing ability are not available mainly due to ethical restrictions in obtaining human eggs for this purpose. Without this information, infertile male patients, including those with mild male factors, tend to choose intracytoplasmic sperm injection (ICSI) as an assisted reproductive technology (ART) procedure to achieve fertilization in vitro. Despite the relatively high fertilization rate of ICSI, reports on the association of increased birth defects in ICSI concepti have begun to surface. This may due partly to damages to gamete chromosomes caused by the invasive and unnatural ICSI procedures. To encourage the use of standard in vitro fertilization (IVF) and intrauterine insemination (IUI), the less invasive ART procedures, for male infertility treatment, there is a need to improve fertilization of human gametes by increasing the fertilization rate of standard IVF and IUI. One possible approach is to treat sperm with oviductin, a protein secreted by the Fallopian tube which has been implicated in enhancing the fertilizing ability of sperm. The main objective of the present proposal is to define sperm quality and fertilizing competence for proper and ethical use of ART in alleviating male infertility utilizing human oviductin. To achieve this goal, a series of interrelated experiments have been designed to produce large amounts of human oviductin from an immortalize cell line originated from the Fallopian tube. The ultimate goal is to improve the fertilziation rate of the less invasive standard IVF and IUI procedures involving couples with male infertility.