Characterization of human sperm populations using conventional parameters, surface ubiquitination, and apoptotic markers.
OBJECTIVE
To directly compare distinct assays proposed to monitor human sperm quality and possibly preselect sperm populations for assisted reproductive technology (ART).


METHODS
Analysis of human sperm sample quality using several methodologies.


METHODS
Academic and clinical institutions.


METHODS
Samples from consenting patients undergoing routine semen analysis or ART.


METHODS
Human sperm samples were analyzed in terms of World Health Organization parameters and processed for annexin V, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling of DNA (TUNEL), and the sperm-ubiquitin tag immunoassay (SUTI). Samples were analyzed both by flow cytometry and fluorescence microscopy.


METHODS
Correlations among apoptotic markers (outer leaflet phosphatidylserine exposure, membrane integrity, and DNA fragmentation), external ubiquitination, and semen parameters in human spermatozoa.


RESULTS
Nonviable sperm, TUNEL-positive cells, and ubiquitin fluorescence intensity means inversely correlate with semen parameters. Apoptotic markers do not correlate with sperm surface ubiquitination. Normozoospermic samples have a higher number of viable cells and lower DNA fragmentation compared with samples with abnormal parameters. Nonviable sperm are more prevalent in samples with low counts and poor morphology but not low motility. Not all sperm with morphologic abnormalities present surface ubiquitination.


CONCLUSIONS
Sperm quality is inversely correlated with lack of viability, DNA fragmentation, and ubiquitin fluorescence intensity means. However, none of the apoptotic markers correlate with ubiquitin labeling. Elimination of defective sperm cells prior to ART using surface markers (annexin V, ubiquitin) seems unwarranted at this stage.
Varum
Sandra
S
Center for Neuroscience and Cell Biology, Department of Zoology, University of Coimbra, Coimbra, Portugal.
Bento
Carla
C
Sousa
Ana Paula M
AP
Gomes-Santos
Carina S S
CS
Henriques
Paula
P
Almeida-Santos
Teresa
T
Teodósio
Cristina
C
Paiva
Artur
A
Ramalho-Santos
João
J
D017304:Annexin A5 / Q000032:analysis; D017209:Apoptosis / Q000502:physiology*; D002470:Cell Survival; D053938:DNA Fragmentation; D005434:Flow Cytometry; D006801:Humans; D020287:In Situ Nick-End Labeling; D008297:Male; D008856:Microscopy, Fluorescence; D010718:Phosphatidylserines / Q000378:metabolism; D011744:Pyrimidinones; D013081:Sperm Motility; D013094:Spermatozoa / Q000737:chemistry / Q000276:immunology / Q000502:physiology*; D025801:Ubiquitin / Q000032:analysis
D017304:Annexin A5; D010718:Phosphatidylserines; D011744:Pyrimidinones; D025801:Ubiquitin; C003954:merocyanine dye