Hyaluronic acid binding ability of human sperm reflects cellular maturity and fertilizing potential: selection of sperm for intracytoplasmic sperm injection.
OBJECTIVE
The current concepts of sperm biochemical markers and the central role of the HspA2 chaperone protein, a measure of sperm cellular maturity and fertilizing potential, are reviewed.


RESULTS
Because HspA2 is a component of the synaptonemal complex, low HspA2 levels and increased frequency of chromosomal aneuploidies are related in diminished maturity sperm. We also suggest a relationship between HspA2 expression in elongating spermatids and events of late spermiogenesis, such as cytoplasmic extrusion and plasma membrane remodeling that aid the formation of the zona pellucida binding and hyaluronic acid binding sites. The presence of hyaluronic acid receptor on the plasma membrane of mature sperm, coupled with hyaluronic acid coated glass or plastic surfaces, facilitates testing of sperm function and selection of single mature sperm for intracytoplasmic sperm injection. The frequencies of sperm with chromosomal disomy are reduced approximately fourfold to fivefold in hyaluronic acid selected sperm compared with semen sperm, comparable to the increase in such abnormalities in intracytoplasmic sperm injection offspring. Hyaluronic acid binding also excludes immature sperm with cytoplasmic extrusion, persistent histones, and DNA chain breaks.


CONCLUSIONS
Hyaluronic acid mediated sperm selection is a novel technique that is comparable to sperm zona pellucida binding. Hyaluronic acid selected sperm will also alleviate the risks related to intracytoplasmic sperm injection fertilization with sperm of diminished maturity that currently cause worldwide concern.
Huszar
Gabor
G
The Sperm Physiology Laboratory, Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, Connecticut 06510, USA. gabor.huszar@yale.edu
Ozkavukcu
Sinan
S
Jakab
Attila
A
Celik-Ozenci
Ciler
C
Sati
G Leyla
GL
Cayli
Sevil
S
D033441:Andrology / Q000379:methods; D000782:Aneuploidy; D005306:Fertilization / Q000502:physiology; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D006820:Hyaluronic Acid / Q000378:metabolism*; D007248:Infertility, Male / Q000378:metabolism / Q000628:therapy*; D008297:Male; D020554:Sperm Injections, Intracytoplasmic; D013094:Spermatozoa / Q000378:metabolism* / Q000502:physiology
D018840:HSP70 Heat-Shock Proteins; C091879:HSPA2 protein, human; D006820:Hyaluronic Acid