Our knowledge of the released human ovulatory components, the cumulus-oocyte complex (COC) and follicular fluid, and their physiological effects on spermatozoa and roles in fertilisation remain poorly characterised. The aim of this study was to use a multi-pronged approach to begin to unravel these interactions and their relation to fertilisation success. Experiments designed to better replicate the physiological environment of the female tract showed environmental modulation of sperm motility. Mean sperm velocity values VSL, VAP and VCL increased by 12.4%, 15%, 16.5% respectively, when exposed to cumulus cells from pregnancy-positive donors, compared to pregnancy-negative donors. Follicular fluid elicited a [Ca2+]i response in spermatozoa that was independent of treatment outcome. The response of spermatozoa exposed to follicular fluid at a 50% (v/v) dilution was a large spike on the front of the ‘classical’ progesterone transient response, which has not been previously reported. Human sperm-zona binding (SZB) studies are hampered by the shortage of oocytes, and thus zona pellucida (ZP) available for research. As a possible source of ZP this study investigates the development of an in vitro model for oogenesis, utilising follicular fluid and cumulus cell co-culture with human embryonic stem cells. The feasibility of SPR technology, using both native and recombinant sources of ZP, to measure SZB and identify possible binding candidates is also assessed. The data in this study addresses just some of the potential effects of the COC and follicular fluid on spermatozoa. Further developments within this area may lead to better diagnostics and treatments for patients undergoing ART, in addition to providing targets for novel contraceptives.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:553220 |
| Date | January 2012 |
| Creators | Frettsome, Rebecca Louise |
| Publisher | University of Birmingham |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://etheses.bham.ac.uk//id/eprint/3512/ |
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