Human papillomavirus sperm infection and assisted reproduction: a dangerous hazard with a possible safe solution.
BACKGROUND
Human papillomavirus (HPV) infection has been demonstrated in the sperm of a large percentage of sexually active males and is associated with an impairment of sperm parameters, with a particular negative impact on sperm motility, suggesting a possible role in male infertility. Conventional sperm selection techniques have a low efficiency in removing HPV.


METHODS
Evaluation of sperm parameters, terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling test to evaluate DNA fragmentation and fluorescence in situ hybridization or immunohistochemistry for HPV were performed on semen samples from infected patients (n= 22), control subjects (n= 13) and on pooled control sperm samples incubated with HPV16-L1 (HPV capsid), before and after direct swim-up and modified swim-up (with added Heparinase-III). Moreover, cytofluorimetry for HPV detection was performed in pooled sperm pre- and post-incubation with HPV 16-L1 before and after direct and modified swim-up. Statistical analysis was performed with a two-tailed Student's t-test.


RESULTS
Direct swim-up reduces the number of HPV-infected sperm by ~24% (P< 0.01), while modified swim-up is able to remove completely HPV DNA both from naturally and artificially infected sperm. Enzymatic treatment with Heparinase-III tended to decrease sperm motility, viability and DNA integrity but the effects were not significant.


CONCLUSIONS
This study shows that Heparinase-III treatment seems not to affect spermatozoa in vitro and suggests that this treatment should be investigated further as a means of preparing sperm from patients who are infected with HPV in order to reduce the risk of HPV infection when using assisted reproduction techniques.
Pathology of Human Reproduction Unit, Section of Clinical Pathology and Centre for Male Gamete Cryopreservation, Department of Histology, Microbiology, and Medical Biotechnologies, University of Padova, Via Gabelli 63, 35121 Padova, Italy.
Andrea
A
Garolla
Andrea
A
Lenzi
Giorgio
G
Palù
Damiano
D
Pizzol
Alessandro
A
Bertoldo
Luca
L
De Toni
Carlo
C
Foresta
D000328:Adult; D000998:Antiviral Agents / Q000494:pharmacology; D004279:DNA, Viral / Q000187:drug effects; D005260:Female; D005307:Fertilization in Vitro / Q000009:adverse effects / Q000379:methods*; D052162:Human papillomavirus 16 / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D020287:In Situ Nick-End Labeling; D008297:Male; D030361:Papillomavirus Infections / Q000517:prevention & control / Q000635:transmission*; D011133:Polysaccharide-Lyases / Q000009:adverse effects / Q000494:pharmacology; D055101:Semen Analysis; D013094:Spermatozoa / Q000187:drug effects / Q000821:virology*
D000998:Antiviral Agents; D004279:DNA, Viral; D011133:Polysaccharide-Lyases; C021349:heparitinsulfate lyase