Infection with high-risk types of papillomavirus in men leads to increased sperm death caused by oxidative stress and a weakened immune response.
- In a recent study, human papillomavirus (HPV) was detected in 19% of semen samples provided by 205 men who underwent initial fertility or urinary tract assessment between 2018 and 2021.
- Patients infected with high-risk human papillomavirus (HR-HPV) types had significantly higher levels of sperm necrosis.
- They also had increased proportions of sperm ROS (reactive oxygen species) and an unexpected reduction in leukocytes in male reproductive cells.
“Human papillomavirus (HPV), a highly prevalent sexually transmitted infection, comprises high-risk (HR-HPV) and low-risk (LR-HPV) viruses. The former pose a high risk of developing malignant tumors, while the latter mainly cause benign warts. Despite increasing awareness of the impact of HPV on men’s health, the influence of HR-HPV and LR-HPV urogenital infections on male fertility potential remains unclear,” said researchers from the Universidad Nacional de Córdoba in Argentina.
HPV: 20 men tested positive for high-risk types of papillomavirus
In a study published in the journal Frontiers in Cellular and Infection Microbiologythey wanted to know whether male urogenital infection with high-risk papillomaviruses is linked to impaired sperm quality, oxidative stress, and inflammation. To find out, the scientists recruited 205 men who had attended a single urology and andrology clinic for an initial assessment of fertility or urinary tract problems between 2018 and 2021. None of them had been vaccinated against papillomavirus. The participants gave a sample of their ejaculate. Then, the presence or absence of HPV and other sexually transmitted infections was determined by PCR.
Of the 205 volunteers, 19% tested positive for HPV. Specifically, 20 men tested positive for high-risk HPV types, while 7 were identified as positive for low-risk HPV types. Most of the HPV-positive adults were infected with only one genotype, but three of them carried two genotypes simultaneously.
Higher levels of sperm necrosis in HR-HPV-infected men
According to the results, men who tested positive for high-risk types of HPV had a higher percentage of dead sperm. The authors also observed that these patients had a significantly lower number of CD45+ white blood cells (leukocytes) in their semen. Another finding was that their sperm could be frequently damaged by oxidative stress, “as judged by their high production of reactive oxygen species (ROS). As a reminder, low levels of ROS are the result of normal sperm function, while high levels can lead to cell membrane rupture, DNA breaks, and uncontrolled, unscheduled cell death.”
Importance of HPV screening
Research has also shown that infections caused by high-risk HPV genotypes have effects on the immune system’s ability to clear the infection. Specifically, the number of immune cells observed in the semen of HR-HPV-positive men was lower, which would lead to reduced movement of leukocytes to the site of infection. “These observations highlight the importance of comprehensive HPV screening, including genotyping, in urology and fertility clinics to understand the progression of infection, potential negative effects on reproductive health, and the oncogenic risks involved,” can be read in the conclusions of the study.
