Thesis (PhD)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: CHAPTER 1 provides literature based background information to emphasize the use of a sequential,
multistep diagnostic schedule for couples in an assisted reproductive program as well as the clinical
importance of sperm morphology as recorded by strict criteria during the diagnostic approach of the
infertile couple. Furthermore, the chapter includes evidence underlining the growing need for the
implementation of the physiologically induced acrosome reaction as an important contribution to the
assisted reproductive program. The zona pellucida-induced acrosome reaction (ZIAR), sperm-zona
interaction as well as computer-assisted semen analyses were investigated. CHAPTER 2 provides
detailed experimental protocols of the materials and methods used in the study. CHAPTERS 3-6 each
represent a separate study that was prepared as a scientific paper and encompass the experimental
research undertaken in the reproductive biology research laboratory at Tygerberg Hospital to address
important aspects of human acrosome processes. In the first study, we aimed to evaluate the
regulatory role of the Gi-like protein during the AR of normal sperm donors and the role of intact
acrosomes during sperm-zona binding. It seems that pertussis toxin-sensitive Gi-like protein in human
spermatozoa plays an important regulatory role in the ZIAR and this underlines the importance of
intact acrosomes during sperm-zona binding. In the second study, we aimed to evaluate the
relationship between the ZIAR and the percentage normal spermatozoa as well as the sperm-ZP
binding potential among men referred for a routine semen analysis. ZIAR testing should become part
of the second level of male fertility investigations, i.e., sperm functional testing, since 15% of the
andrology referrals revealed an impaired AR response to solubilized ZP. In the third study, we aimed
to evaluate the possible relationships between the sperm morphology, the acrosome responsiveness to
solubulized human ZP and the sperm-zona binding potential among consecutive andrology referrals
and randomly selected IVF cases. ZIAR results provide further information regarding dysfunctional
sperm and can be used as an additional diagnostic test since the results predicted fertilization failure
during IVF treatment. In the fourth study, we aimed to evaluate changes in the sperm motion
characteristics and the occurrence of hyperactivated motility after exposure to ZP among andrology
referrals. Solubilized human ZP induces hyperactivated motility among sperm populations that have
been capacitated under laboratory conditions. Capacitated spermatozoa have an elevated percentage
hyperactivated cells that correlate with the percentage normal spermatozoa in the ejaculate.
CHAPTER 7, the general discussion, is brief and concise to avoid unnecessary repetition, underlines
the validity of a sequential, multistep diagnostic approach and concludes with the recommendation that
the ZIAR should form part of the diagnostic tools in the assisted reproductive program. / AFRIKAANSE OPSOMMING: HOOFSTUK 1 bestaan uit ’n omvattende agtergrondstudie wat bestaan uit die ontwikkeling van
diagnostiese toetse, die hantering van die egpaar in die reproduktiewe ondersteunings-program asook
op die kliniese belang van spermmorfologie. Die toenemende behoefte aan die implementering van die
fisiologies-geinduseerde akrosoomreaksie, as ’n belangrike bydrae tot die reproduktiewe
ondersteuningsprogram, word ook beklemtoon. Die zona pellucida geinduseerde akrosoomreaksie
(ZIAR), sperm-zonabinding asook rekenaar-bemiddelde semenanalises is ondersoek. HOOFSTUK 2
dek gedetailleerde eksperimentele protokolle van die materiale en metodes wat in die studie gebruik is.
HOOFSTUKKE 3-6 behandel die eksperimentele navorsing wat in die laboratorium van die
reproduktiewe biologie-eenheid te Tygerberg hospitaal uitgevoer is en wat as ses afsonderlike
wetenskaplike publikasies aangebied word. Die doel van die eerste studie was om die regulerende rol
van Gi-proteiene tydens die AR van normale spermdonors asook die rol van intakte akrosome tydens
sperm-zonabinding te evalueer. Dit kom voor asof Gj-protei'ene in spermatozoa ’n belangrike
regulerende rol in die ZIAR speel. Dit beklemtoon die belangrikheid van intakte akrosome tydens
sperm-zonabinding. Die doel van die tweede studie was om die verhouding tussen die ZIAR en die
persentasie normale spermatozoa asook die sperm-zonabindingspotensiaal tussen mans wat vir ’n
roetine semenanalise verwys is te evalueer. ZIAR-toetsing moet deel uitmaak van die tweede vlak van
manlike fertiliteitsondersoeke, d.w.s. funksionele toetsing, aangesien 15% van die andrologie pasiente
’n verswakte AR respons tot opgeloste ZP openbaar. In die derde studie was die doel om die
moontlike verhoudinge tussen sperm-morfologie, die ZIAR en die sperm-zonabindingspotensiaal
onder opeenvolgende andrologie-pasiente asook lukraak geselekteerde IVB-pasiente te evalueer. Die
ZIAR-resultate bied verdere informasie aangaande disfunksionele spermatozoa en kan gebruik word as
’n addisionele diagnostiese toets aangesien hierdie resultate mislukte bevrugting tydens IVB
behandeling voorspel. Die vierde studie het ten doel gehad om veranderinge in spermmotiliteitseienskappe
asook hiperaktiwiteit na die blootstelling aan opgeloste zona onder andrologiepasiente
te evalueer. Daar is afgelei dat opgeloste menslike zona hiperaktiwiteit induseer in
spermpopulasies wat onder gunstige laboratoriumkondisies gekapasiteer is. Die gekapasiteerde
spermatozoa het ’n verhoogde persentasie gehiperaktiveerde spermatozoa getoon wat met die
persentasie normale spermatozoa in die ejakulaat korreleer. In HOOFSTUK 7 word aangetoon dat dit
noodsaaklik is om die diagnostiese skedule by die hantering van die onvrugbare egpaar te gebruik
asook dat die ontwikkeling van die funksionele toestand belangrik is vir die bepaling van ZIAR.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/53630 |
| Date | 12 1900 |
| Creators | Bastiaan, Hadley Saville |
| Contributors | Franken, D. R., Menkveld, R., Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Obstetrics and Gynaecology. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
| Format | 139 p. : ill. |
| Rights | Stellenbosch University |
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