An altered total seminal plasma glycosylation has been associated with male infertility, and the highly abundant seminal plasma glycoprotein prostate-specific antigen (PSA) plays an important role... Show moreAn altered total seminal plasma glycosylation has been associated with male infertility, and the highly abundant seminal plasma glycoprotein prostate-specific antigen (PSA) plays an important role in fertilization. However, the exact role of PSA glycosylation in male fertility is not clear. To understand the involvement of PSA glycosylation in the fertilization process, analytical methods are required to study the glycosylation of PSA from seminal plasma with a high glycoform resolution and in a protein-specific manner. In this study, we developed a novel, high-throughput PSA glycopeptide workflow, based on matrix-assisted laser desorption/ionization-mass spectrometry, allowing the discrimination of sialic acid linkage isomers via the derivatization of glycopeptides. The method was successfully applied on a cohort consisting of seminal plasma from infertile and fertile men (N = 102). Forty-four glycopeptides were quantified in all samples, showing mainly complex-type glycans with high levels of fucosylation and sialylation. In addition, N,N-diacetyllactosamine (LacdiNAc) motives were found as well as hybrid-type and high mannose-type structures. Our method showed a high intra- and interday repeatability and revealed no difference in PSA glycosylation between fertile and infertile men. Next to seminal plasma, the method is also expected to be of use for studying PSA glycopeptides derived from other biofluids and/or in other disease contexts. Show less
Overbeek, A.; Berg, M. van den; Louwe, L.; Wendel, E.; Kuile, M. ter; Kaspers, G.; ... ; Hilders, C. 2014
In this thesis two studies are presented dealing with diagnostic and therapeutic strategies in reproductive medicine. The first subject is to investigate whether hysterosalpingography (HSG) prior... Show moreIn this thesis two studies are presented dealing with diagnostic and therapeutic strategies in reproductive medicine. The first subject is to investigate whether hysterosalpingography (HSG) prior to laparoscopy and dye should be maintained as a diagnostic procedure in the routine fertility workup. The results of a randomized controlled trial with or without HSG showed that routine use of HSG at an early stage in the fertility workup prior to laparoscopy and dye does not influence cumulative pregnancy rate compared to routine use of laparoscopy without HSG. HSG can be omitted form the routine investigation in the fertility workup and should only be applied for specific conditions like contraindication for laparoscopy or examining tubal mucosal fold configuration when tubal microsurgery is considered. Chlamydia antibody testing and endovaginal ultrasound may replace HSG as screening test prior to laparoscopy. The second subject focuses on therapy in reproductive medicine with the clinically relevant question whether adverse perinatal outcome is related to assisted conception in both singleton and twin pregnancies. We describe the results of a systematic review of 25 controlled studies. We concluded that singleton pregnancies conceived after assisted conception have significantly worse perinatal outcomes than naturally conceived singletons, but this is substantially less so for twins. Show less
