No abstract

The testis-expressed chaperone protein, HspA2 (previously creatine kinase M isoform) was established as a measure of human sperm cellular maturity, function and fertility. The presence of HspA2 in the synaptonemal complex is likely to link low HspA2 expression and increased frequency of chromosomal aneuploidies in arrested-maturity spermatozoa. A relationship also exists between HspA2 expression in elongating spermatids and the associated spermatogenetic events, including plasma membrane remodelling and the formation of zona pellucida and hyaluronic acid (HA) binding sites. The HA receptor of mature spermatozoa, when coupled with HA-coated slides and/or Petri dishes, allows visual observation of sperm-HA binding, providing a basis for sperm maturity testing, a major improvement in semen evaluation, and selection of mature spermatozoa for intracytoplasmic sperm injection (ICSI). Thus, in HA-selected spermatozoa the frequency of chromosomal disomy and diploidy is reduced 4- to 6-fold compared with semen sperm fractions. This reduction is similar to the increase in numerical chromosomal aberrations in ICSI children. Combined studies of sperm shape and chromosome probes demonstrated that sperm morphology does not aid selection of haploid spermatozoa. The HA-mediated sperm selection is a novel and efficient technique that may alleviate potential problems related to ICSI fertilization with visually selected spermatozoa.

In order to estimate the impact of laparoscopic stripping of endometriomas on the ovarian follicular reserve, 43 normo-ovulatory women were studied by endocrine (anti-Müllerian hormone (AMH), FSH, LH, inhibin B, oestradiol) and ultrasonographic (antral follicle count (AFC)) methods before surgery, and 3 and 9 months after surgery. The operation was performed by experienced laparoscopists, particularly aware of the need to avoid damaging the healthy part of the ovary. Serum AMH concentrations significantly decreased after the operation (1.4±0.2 ng/ml after 3 months and 1.3±0.3 ng/ml after 9 months versus 3.0±0.4 ng/ml before surgery; P<0.0001), whereas basal FSH, LH, oestradiol and inhibin B concentrations remained unchanged. The volume of the operated ovary significantly diminished after surgery (P<0.0001), whereas the AFC was not significantly altered. Overall, the data show that laparoscopic stripping of endometriomas reduces ovarian reserve. The significant decrease of AMH after surgery confirms that part of the healthy ovarian pericapsular tissue, containing primordial and preantral follicles, is removed or damaged despite all the surgical efforts to be atraumatic. This must be carefully considered when laparoscopic cystectomy surgery is scheduled for patients with no relevant symptoms besides infertility or with already small ovarian reserve.

The expression of a 70 kDa chaperone protein, HspA2 (formerly called CK-M), has been identified in mature human spermatozoa. The central role of HspA2 has been established, as the expression level of this protein is related to sperm cellular maturity, DNA integrity, chromatin maturity, chromosomal aneuploidy frequency and sperm function, including fertilizing potential. The spermiogenetic events of cytoplasmic extrusion and remodelling of the plasma membrane, which facilitate the formation of zona pellucida binding site(s) in human spermatozoa, are related. Finally, the presence of the hyaluronic acid (HA) receptor on the plasma membrane of mature sperm coupled with the HA-coated slide sperm-binding assay, facilitates the testing of infertile men and the selection of single mature spermatozoa for ICSI. Because mature spermatozoa have no residual cytoplasm, the HA-bound sperm fraction is also enriched in spermatozoa that are normal by the Kruger strict morphology method.

No abstract