No increased sperm DNA fragmentation index in semen containing human papillomavirus or herpesvirus

Molecular study of the presence and transcriptional activity of HPV in semen

PURPOSE

Human Papillomavirus (HPV) in semen represents a controversial topic. Recent evidence suggests a correlation with poor semen quality, but its detection is still unstandardized in this biological fluid. Thus, the aims of this study were to verify the ability of nested PCR to reveal HPV-DNA in semen; to evaluate association of seminal HPV with sperm parameters and risk factors for infection; to investigate the rate of HPV-DNA positivity in patients with and without risk factors; to assess HPV transcriptional activity.

METHODS

We enrolled sexually active men and collected clinical and anamnestic data during andrological and sexually transmitted infections (STIs) evaluation. For each patient, we performed semen analysis and nested PCR to detect HPV-DNA in semen. In positive semen samples, we proceeded with genotyping and RNA quantification to detect HPV transcriptional activity.

RESULTS

We enrolled 185 men (36.0 ± 8.3 years), of which 85 with (Group A) and 100 without HPV risk factors (Group B). Nested PCR was able to reveal HPV-DNA in semen, discovering a prevalence of 8.6% (11.8% in Group A and 6% in Group B, respectively). We observed no correlation between sperm quality and seminal HPV. Genital warts and previous anogenital infection were significantly associated with the risk of HPV positivity in semen. Moreover, no viral transcriptional activity was detected in positive semen samples.

CONCLUSIONS

Our study suggests that searching for seminal HPV could be important in patients both with and without risk factors, especially in assisted reproduction where the risk of injecting sperm carrying HPV-DNA is possible.

HPV-related diseases in male patients: an underestimated conundrum

PURPOSE

Human papillomavirus (HPV) infection is the most common sexually transmitted disease, in males and females worldwide. While the role of HPV in female diseases is well known and largely studied, males have negligibly been included in these programs, also because the proportion of women suffering and dying from HPV-related diseases is much larger than men. The aim of this review is to focus on HPV-related diseases in male patients.

METHODS

We performed a literature analysis on the electronic database PubMed. We considered randomized trials, observational and retrospective studies, original articles having as topic the relationship between HPV male infection and the following items: oral, anal penile cancers, warts, condylomas, male infertility, altered sperm parameters, anti-sperm antibodies (ASA). We also included experimental in vitro studies focused on the effects of HPV infection on oocyte fertilization, blastocyst development, and trophoblastic cell invasiveness. In addition, studies describing the adjuvant administration of the HPV vaccination as a possible strategy to promote HPV clearance from semen in infected males were included.

RESULTS

Regarding head and neck HPV-related diseases, the most important non-neoplastic disease is recurrent respiratory papillomatosis (RRP). Regarding neoplastic diseases, the proportion of head and neck cancers attributable to HPV has increased dramatically worldwide. In addition, nowadays, it is thought that half of head and neck squamous cell carcinomas (HNSCCs) cases in the United States are caused by infection with high-risk HPV. HPV is noteworthy in andrological practice too. It was described as having a high HPV prevalence, ranging between 50 and 70%, in male penile shaft, glans penis/coronal sulcus, semen as well as in scrotal, perianal, and anal regions. Moreover, in male patients, HPV infection has been associated, among other diseases, with penile cancers. HPV semen infection has been reported in about 10% in men from the general population and about 16% in men with unexplained infertility, although these data seem widely underestimated according to clinical experience. In particular, HPV semen infection seems to be most related to asthenozoospermia and to anti-sperm antibodies (ASAs).

CONCLUSIONS

HPV infection represents a health problem with a detrimental social and public impact. Despite this evidence, little has been done to date to widely promote vaccination among young males.

Semen human papillomavirus (HPV) shedding in males: frequency, clinical significance, and reproductive outcomes—literature review

Background

The interest in the HPV status of the male has risen after the discovery of HPV shedding in the semen. To date, there is no consensus on the true prevalence of male HPV infection, yet there is a rising body of evidence suggesting that male HPV infection might negatively affect the sperm parameters.

Main body

The concern that HPV can lead to a couple’s infertility and affect reproductive outcomes had increased after the multiple publications of semen criteria perturbations specifically the asthenospermia associated with HPV infection. An extensive literature review was performed to define the actual frequency of male HPV infection as well as the true extent of sperm analysis perturbations related to the HPV illness. We also intended to define the impact of these infections on reproductive outcomes and to highlight any treatment plans for affected couples.

Conclusion

HPV is a prevalent disease with a rising concern among the male populations given the suggested impact on sperm motility as well as the pregnancy and miscarriage rates post-ART treatment. Vaccines are being studied now as a possible infertility adjunct treatment for males who are already infected.

Human Papillomavirus (HPV) Infection and Its Impact on Male Infertility

Nowadays, the striking numbers of infertile couples that turn to assisted reproductive technologies (ART) drive the research toward a more comprehensive understanding of the underlying causes. Male factors contribute to the inability to conceive in half of the cases, and it has been suggested that sexually transmitted infections could have a role in the onset of spermatozoa impairments. Since the impact of HPV infection on sperm quality and sperm DNA integrity is debated, we wanted to analyze its impact on conventional seminal parameters and the sperm DNA fragmentation index (DFI). Therefore, 117 semen samples of patients undergoing IVF were evaluated for the following characteristics: HPV DNA detection and sperm DNA fragmentation, concentration, motility, and morphology. The results showed a higher rate of HPV-negative patients (59.8% vs. 40.2%) and no HPV-related effect on DFI, sperm concentration, total sperm number, and total motility. Only progressive motility and morphology were found as significantly influenced by HPV positivity. Moreover, we observed a statistically significant difference in DFI when comparing high-risk HPV (HR-HPV) and low-risk HPV (LR-HPV) genotypes. Our data suggest that the presence of any HPV type, whatever the exact localization of the virions, can impair some sperm parameters, while HR-HPVs specifically affect the integrity of spermatozoa DNA.

Negative Impact of Elevated DNA Fragmentation and Human Papillomavirus (HPV) Presence in Sperm on the Outcome of Intra-Uterine Insemination (IUI)

We wanted to determine the sperm DNA fragmentation index (DFI) cutoff for clinical pregnancies in women receiving intra-uterine insemination (IUI) with this sperm and to assess the contribution of Human Papillomavirus (HPV) infection on sperm DNA damage and its impact on clinical pregnancies. Prospective non-interventional multi-center study with 161 infertile couples going through 209 cycles of IUI in hospital fertility centers in Flanders, Belgium. Measurement of DFI and HPV DNA with type specific quantitative PCRs (HPV 6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66 and 68) in sperm before its use in IUI. Clinical pregnancy (CP) rate was used as the outcome to analyze the impact on fertility outcome and to calculated the clinical cutoff value for DFI. A DFI criterion value of 26% was obtained by receiver operating characteristic (ROC) curve analysis. Couples with a male DFI > 26% had significantly less CPs than couples with DFI below 26% (OR 0.0326; 95% CI 0.0019 to 0.5400; p = 0.017). In sperm, HPV prevalence was 14.8%/IUI cycle. Sperm samples containing HPV had a significantly higher DFI compared to HPV negative sperm samples (29.8% vs. 20.9%; p = 0.011). When HPV-virions were present in sperm, no clinical pregnancies were observed. More than 1 in 5 of samples with normal semen parameters (17/78; 21.8%) had an elevated DFI or was HPV positive. Sperm DFI is a robust predictor of clinical pregnancies in women receiving IUI with this sperm. When DFI exceeds 26%, clinical pregnancies are less likely and in vitro fertilization techniques should be considered.

Seminal human papillomavirus infection and reproduction: a systematic review and meta-analysis

BACKGROUND

The impact of human papillomavirus (HPV) on male fertility and associated reproductive outcomes has not been clarified.

OBJECTIVES

To elucidate the prevalence of seminal HPV infection and assess the associated effects on seminal parameters, male infertility, and reproductive outcomes.

MATERIALS AND METHODS

A systematic review and meta-analysis was performed in accordance with PRISMA guidelines. A search was performed using PubMed, MEDLINE, SCOPUS, and Cochrane databases. Studies published until November 2019 were included. HPV prevalence, risk of infertility, seminal parameters, and reproductive outcomes were evaluated among the general population and infertile men.

RESULTS

Fifty studies met the inclusion criteria. The prevalence of seminal HPV infection is significantly higher in infertile compared to the general population (20.9% versus 8.2%). A significant association between seminal HPV infection and male infertility (OR 3.30, 95% CI 1.87-5.84), even when adjusting for female infertility (OR 3.02, 95% CI = 2.11-4.33) was founded. In addition, HPV infection is related to a significant decrease in progressive motility (DM -10.35, IC -13.75, -6.96), a low sperm morphology score (DM -2.46, 95% CI -3.83, -1.08), and a significant increase in the sperm DNA fragmentation index (7.24, 95% CI 4.44.10.03) compared with HPV-negative patients. It was also observed an increased risk of miscarriage (OR 5.13, 95% CI 2.40,10.94), and a reduced chance of ongoing pregnancy (OR 0.33, IC 95% 0.13,0,82) in patients undergoing ART with seminal HPV infection.

DISCUSSION

Infertile men have a higher prevalence of seminal HPV infection compared to the general population, regardless of the HPV genotype detected.

CONCLUSIONS

HPV in semen may have an impact in sperm quality and reproductive outcomes. Additional well-designed studies are warranted to improve the quality of evidence.

High-risk human papillomavirus in semen is associated with poor sperm progressive motility and a high sperm DNA fragmentation index in infertile men

STUDY QUESTION

Does the presence of human papillomavirus (HPV) in semen impact seminal parameters and sperm DNA quality in white European men seeking medical help for primary couple's infertility?

SUMMARY ANSWER

HPV seminal infections involving high-risk (HR) genotypes are associated with impaired sperm progressive motility and sperm DNA fragmentation (SDF) values.

WHAT IS KNOWN ALREADY

HPV is commonly present in semen samples. However, whether the presence of HPV in semen is actually associated with impaired sperm parameters and SDF values have yet to be elucidated.

STUDY DESIGN, SIZE, DURATION

In this cross-sectional study, complete demographic, clinical and laboratory data from 729 infertile men were analysed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Health-significant comorbidities were scored with the Charlson comorbidity index (CCI). Serum hormones and SDF index (measured by the sperm chromatin structure assay [SCSA]) were measured in every patient (SDF ≥30% was defined as pathological). Semen analysis was based on 2010 World Health Organisation reference criteria. Amplification by nested PCR was used to detect HPV-DNA sequences in semen samples. Descriptive statistics and linear regression models were used to test the association between the presence of HPV and clinical and seminal characteristics in the whole cohort.

MAIN RESULTS AND THE ROLE OF CHANCE

The overall rate of HPV positivity was 15.5% (113/729). Overall, 78/729 (10.7%) and 35/729 (4.8%) patients had HR HPV+ and low-risk HPV+, respectively. HPV16 was the most prevalent type (22.1%), followed by HPV43 (10.6%), HPV56 and HPV42 (both 8.8%). No differences were found in terms of clinical and hormonal characteristics between patients with or without seminal HPV. Sperm progressive motility was significantly lower (P = 0.01) while SDF values were higher (P = 0.005) in HPV+ men compared to those with no HPV. In particular, HR HPV+ men had lower sperm progressive motility (P = 0.007) and higher SDF values (P = 0.003) than those with a negative HPV test. Univariable analysis showed that HR HPV+ was associated with impaired sperm progressive motility (P = 0.002) and SDF values (P = 0.003). In the multivariable analysis, age, FSH levels and testicular volume were significantly associated with impaired sperm progressive motility (all P ≤ 0.04). Conversely BMI, CCI, smoking habits and HPV status were not. Only age (P = 0.02) and FSH (P = 0.01) were significantly associated with SDF, after accounting for BMI, CCI, testicular volume, smoking habits and HPV status.

LIMITATIONS, REASONS FOR CAUTION

Main limitations are the cross-sectional design of our study and the relatively small sample size of the subgroups. Additional limitations are the lack of a control group of normal fertile men and the lack of follow-up testing to check the clearance or the persistence of HPV in semen after a 6-12 months.

WIDER IMPLICATIONS OF THE FINDINGS

Overall, these observations point out the importance of an accurate investigation of seminal HPV presence in everyday clinical practice in the diagnostic work-up of infertile men.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used. There are no competing interests.

From Ancient to Emerging Infections: The Odyssey of Viruses in the Male Genital Tract

The male genital tract (MGT) is the target of a number of viral infections that can have deleterious consequences at the individual, offspring, and population levels. These consequences include infertility, cancers of male organs, transmission to the embryo/fetal development abnormalities, and sexual dissemination of major viral pathogens such as human immunodeficiency virus (HIV) and hepatitis B virus. Lately, two emerging viruses, Zika and Ebola, have additionally revealed that the human MGT can constitute a reservoir for viruses cleared from peripheral circulation by the immune system, leading to their sexual transmission by cured men. This represents a concern for future epidemics and further underlines the need for a better understanding of the interplay between viruses and the MGT. We review here how viruses, from ancient viruses that integrated the germline during evolution through old viruses (e.g., papillomaviruses originating from Neanderthals) and more modern sexually transmitted infections (e.g., simian zoonotic HIV) to emerging viruses (e.g., Ebola and Zika) take advantage of genital tract colonization for horizontal dissemination, viral persistence, vertical transmission, and endogenization. The MGT immune responses to viruses and the impact of these infections are discussed. We summarize the latest data regarding the sources of viruses in semen and the complex role of this body fluid in sexual transmission. Finally, we introduce key animal findings that are relevant for our understanding of viral infection and persistence in the human MGT and suggest future research directions.

Seminal human papillomavirus originates from the body surface and is not a frequent aetiological factor in azoospermia

Human papillomavirus (HPV) DNA has been detected in the testis tissue of 6.5% of 185 men with non‐obstructive azoospermia (NOA). Others have suggested that seminal HPV originates from contamination from the genital skin and mucosa. One hundred unselected azoospermic men and 43 normal men undergoing vasectomy were recruited. Testicular biopsies for HPV examination were collected from all the men. Additionally, the normal men undergoing vasectomy delivered a semen sample and had a swab for HPV examination taken from the genital skin before vasectomy. A piece of each Vas deferens obtained during the vasectomy was examined for the presence of HPV. Two of the primarily azoospermic men were shown to have cryptozoospermia. It was not possible to detect HPV in the testis tissue of any of the included 98 azoospermic men or the 43 proven fertile men. In the proven fertile men, HPV DNA was detected in the semen of 15 men (35%), on the genital skin of 28 men (65%), and in the Vas deferens in three cases (7%). In 13 (87%) men with HPV‐positive semen samples, HPV DNA was also detected in the skin swabs, and in 11 men (73%), identical HPV genotypes were found in the two locations.

DNA fragmentation index and human papilloma virus in males with previous assisted reproductive technology failures

OBJECTIVE

This study was designed to evaluate the prevalence of Human Papilloma Virus (HPV) in semen and document the cycle outcomes in couples with previous intra-cytoplasmic sperm injection (ICSI) failures.

MATERIAL AND METHODS

One hundred and seventeen couples with at least two ICSI attempts were included in the study. HPV infection in semen and DNA fragmentation in samples were analyzed by commercially available kits. The percentage of spermatozoa with fragmented DNA (DNA fragmentation index: DFI) was determined during fluorescence microscopic examination as previously described. The cycle outcomes of couples with or without HPV infected male partners were recorded.

RESULTS

According to our results, the prevalence of HPV was 7.7% in asymptomatic males with at least two previous ICSI failures. The increased DFI (>30%) was observed in 82.9% of the cases. In HPV-positive cases significantly lower number of good quality embryos were obtained. The implantation and pregnancy rates were similar in infected and non-infected males (p>0.05). The early miscarriage rate was slightly higher in HPV- positive group (33% vs. 10%, p>0.05).

CONCLUSION

In cases with previous ICSI failures, the prevalence of HPV infection in semen is not higher than previously reported infertile populations. The reproductive outcome might be impaired in HPV-positive semen due to lower number of good quality embryos, which needs to be clarified by further large population-based studies.

HPV-DNA sperm infection and infertility: from a systematic literature review to a possible clinical management proposal

The objectives of this study were to investigate the implications of human papillomavirus (HPV) sperm infection on male fertility, impairment of sperm parameters, and possible alteration of sperm nuclear status and to identify a possible effective management of infertile men with HPV sperm infection. We employed a systematic review and clinical management proposal at the Centers for Reproductive and Health care for treating infertile male patients with HPV infection. Literature search was carried out in electronic databases in the last two decades. We focused our attention on: (i) HPV sperm prevalence (ii) HPV-related alteration of sperm parameters; (iii) molecular mechanisms of HPV semen infection and infertility. The main outcome measures were HPV prevalence in infertile male patients and semen parameters. The prevalence of HPV sperm infection ranges between 2 and 31% in men from general population and between 10 and 35.7% in men affected by unexplained infertility. The presence of HPV in semen is associated with an impairment of sperm motility and the presence of anti-sperm antibodies. The molecular mechanisms underlying impairment of sperm motility apparatus need further evaluations. A greater attention should be applied to assess HPV sperm infection, particularly in men undergoing assisted reproduction techniques cycle for male infertility or sperm banking. It would be useful to perform HPV test and fluorescent in situ hybridization analysis for HPV in semen from these patients both at first admission, to define the possible presence and localization of semen infection, and after 6 months, to assess the possible virus clearance retrieval on normal sperm parameters.

Prevalence of human papillomaviruses in semen: a systematic review and meta-analysis

STUDY QUESTION

What is the prevalence of human papillomavirus (HPV) in semen?

SUMMARY ANSWER

HPV is present in the semen of asymptomatic men, with a pooled prevalence in a random effects meta-analysis of populations seeking fertility evaluation/treatment of 16%, versus 10% in other populations.

WHAT IS KNOWN ALREADY

The main risk of donor insemination (DI) is known to be contamination with an infectious agent. HPV is the necessary cause of cervical cancer, and plays an etiologic role in other anogenital cancers. Although it is known to be prevalent and sexually transmitted, donor semen specimens are not tested for the presence of HPV.

STUDY DESIGN, SIZE, DURATION

A systematic review and meta-analysis of studies published between January 1980 and June 2013 were performed. Variables collected included characteristics of study populations, method of semen preparation, HPV DNA detection and genotyping, HPV types targeted and proportion of HPV positivity.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Two investigators independently assessed the studies for inclusion in the review and abstracted the data, while others reviewed the extracted data in detail. Studies were included if they provided data on HPV DNA prevalence in semen and PCR-based methods were used. For the meta-analysis, reports were separated according to the study populations, creating two distinct subgroups: populations seeking fertility evaluation/treatments, and other populations. Data were analysed using a random effects model for each subpopulation.

MAIN RESULTS AND THE ROLE OF CHANCE

The literature search identified 285 studies, and in the 27 studies that were included the HPV DNA prevalence in 4029 semen samples varied from 0 to 100%. The three studies focusing on sperm donors identified HPV DNA in 26.3, 7.5 and 16.0% of semen samples. HPV-16 was the most common type overall. The pooled prevalence in a random effects meta-analysis of seven studies focusing on infertile populations was 16% [95% confidence interval (CI): 10-23%] versus 10% (95% CI: 7-14%) in 11 reports focusing on other populations.

LIMITATIONS, REASONS FOR CAUTION

First, despite defining clinically relevant subgroups, substantial heterogeneity remained. Secondly, although we retrieved data from reports in English or French only, after reviewing the five reports in other languages only two more could have been added and, as their prevalence estimates were similar to those of studies included in our review, we do not believe that exclusion of these reports biased our results or conclusions.

WIDER IMPLICATIONS OF THE FINDINGS

HPV DNA can be found in donor semen and preliminary studies confirm genome activity. For this reason, and although the exact consequences of insemination with HPV-infected semen (cervical infections/lesions, impact on success rate of DI) remain to be clarified, we believe that HPV-infected sperm should be considered a health risk unless well-designed studies prove otherwise. The development and validation of adequate sperm washing techniques before DI appears to be a promising option.

STUDY FUNDING/COMPETING INTEREST(S)

C.L. and P.M. have no conflicts of interests relevant to the submitted work. H.T. has served as a consultant and on advisory boards and has received speaker fees and travel assistance from Merck-Frosst Canada, Glaxo SmithKline Pharmaceuticals, Belgium and Gilead Sciences. F.C. has received grants through his institution from Merck and Roche, as well as honoraria from Merck and Roche for lectures on HPV. M.-H.M. has received grants though her institution from Merck and Qiagen and lecture honoraria from Merck and GSK for conferences on HPV and best practices in cervical cancer prevention.

TRIAL REGISTRATION NUMBER

N/A.