Human Sperm Immotility Caused by Degeneration in the Epididymis

Objective To investigate whether sperm immotility was caused by degeneration in the epididymis Methods Five patients with totally immotile sperm were selected in this study. Testicular biopsy was used to obtain testicular sperm to evaluate sperm motility. The combined hypoosmotic swelling eosin Y exclusion test was carried out to determine the sperm head and tail membrane integrity for the ejaculated and the testicular sperm. The ultrastructure of ejaculated sperm was examined by transmission electron microscope. Results No motile sperm were found in the ejaculated semen samples from 5 patients, whereas 2% to 11% motile testicular sperm extracted from the testicular biopsy tissues were observed. The percentage of testicular sperm with intact head and tail membranes was higher than that of the ejaculated sperm (P<0.01). Ultrastructure of the ejaculated sperm showed marked degenerative features. Seminal plasma from patients did not influence the motility of normal donor sperm. Conclusion Sperm could undergo degenerative changes during transit through and /or storage in the epididymis, which led to lose sperm motility in these patients. Using motile testicular sperm would benefit the treatment for such cases.

Novel mutation in ODF2 causes multiple morphological abnormalities of the sperm flagella in an infertile male

Numerous genes have been associated with multiple morphological abnormalities of the sperm flagella(MMAF),which cause severe asthenozoospermia and lead to male infertility,while the causes of approximately 50%of MMAF cases remain unclear.To reveal the genetic causes of MMAF in an infertile patient,whole-exome sequencing was performed to screen for pathogenic genes,and electron microscope was used to reveal the sperm flagellar ultrastructure.A novel heterozygous missense mutation in the outer dense fiber protein 2(ODF2)gene was detected,which was inherited from the patient’s mother and predicted to be potentially damaging.Transmission electron microscopy revealed that the outer dense fibers were defective in the patient’s sperm tail,which was similar to that of the reported heterozygous Odf2 mutation mouse.Immunostaining of ODF2 showed severe ODF2 expression defects in the patient’s sperm.Therefore,it was concluded that the heterozygous mutation in ODF2 caused MMAF in this case.To evaluate the possibility of assisted reproductive technology(ART)treatment for this patient,intracytoplasmic sperm injection(ICSI)was performed,with the help of a hypo-osmotic swelling test and laser-assisted immotile sperm selection(LAISS)for available sperm screening,and artificial oocyte activation with ionomycin was applied to improve the fertilization rate.Four ICSI cycles were performed,and live birth was achieved in the LAISS-applied cycle,suggesting that LAISS would be valuable in ART treatment for MMAF.

Homogeneous Microscopic Abnormalities in Sperm Morphology and Immotility as A Cause of Male Infertility

Objective To study the identification of the cause of specific sperm abnormatities. Methods Two adult men with specific alterations in sperm morphology causing 100% immobility were included in this study. The study of sperm used： transmission electron microscopy （both patients）; apoptotic markers, DNA fragmentation test and fluorescence in-situ hybridization （patient 1） and immunoeytochemistry study of sperm flagellum using anti-β tubulin antibodies and ciliary activity test （patient 2）.Results Increased DNA fragmentation （52.6%） and apoptosis biomarkers were detected in patient 1, and loss of the central pair of mierotubules in patient 2 （‘9＋0＇ axoneme）; the nasal ciliary activity was normal. Conclusion Results suggest an apoptotic origin of the abnormalities in the sperm from patient 1 and dysplasia of the fibrous sheath in patient 2.