The role of ATP in the differential ability of Sr2+ to trigger Ca2+ oscillations in mouse and human eggs.

At fertilization in mice and humans, the activation of the egg is caused by a series of repetitive Ca2+ oscillations which are initiated by phospholipase-C(zeta)ζ that generates inositol-1,4,5-trisphophate (InsP3). Ca2+ oscillations and egg activation can be triggered in mature mouse eggs by incubation in Sr2+ containing medium, but this does not appear to be effective in human eggs. Here, we have investigated the reason for this apparent difference using mouse eggs, and human eggs that failed to fertilize after IVF or ICSI.

Non-invasive molecular assessment of human embryo development and implantation potential.

In vitro fertilization (IVF) is the most common assisted reproductive technology used to treat infertility. Embryo selection for transfer in IVF cycles relies on the morphological evaluation by embryologists, either by conventional microscopic assessment or more recently by time-lapse imaging systems. Despite the introduction of time-lapse imaging improvements in IVF success rates have failed to materialize, therefore alternative approaches are needed.

Antigen unmasking enhances visualization efficacy of the oocyte activation factor, phospholipase C zeta, in mammalian sperm.

Study Question: Is it possible to improve clinical visualization of phospholipase C zeta (PLCζ) as a diagnostic marker of sperm oocyte activation capacity and male fertility?

Summary Answer: Poor PLCζ visualization efficacy using current protocols may be due to steric or conformational occlusion of native PLCζ, hindering antibody access, and is significantly enhanced using antigen unmasking/retrieval (AUM) protocols.

What Is Known Already: Mammalian oocyte activation is mediated via a series of intracellular calcium (Ca) oscillations induced by sperm-specific PLCζ. PLCζ represents not only a potential clinical therapeutic in cases of oocyte activation deficiency but also a diagnostic marker of sperm fertility.

Functional disparity between human PAWP and PLCζ in the generation of Ca2+ oscillations for oocyte activation.

Mammalian oocyte activation is mediated by cytosolic calcium (Ca(2+)) oscillations initiated upon delivery of a putative 'sperm factor' by the fertilizing sperm. Previous studies suggest the identity of this sperm factor as the testis-specific phospholipase C-zeta (PLCζ). Recently, a post-acrosomal sheath WW domain-binding protein (PAWP) has been proposed as an alternative sperm factor candidate, following a report that human PAWP protein and cRNA elicited Ca(2+) oscillations in mouse and human oocytes.

Improved FSH sensitisation and aromatase assay in human granulosa-lutein cells.

Granulosa-lutein (GL) cells from follicular aspirates from women undergoing in-vitro fertilization (IVF) treatment are usually refractory to follicle stimulating hormone (FSH) regarding the induction and/or maintenance of aromatase activity which converts androgens (e.g. testosterone) to oestrogens.