P-031 Presence of HPV 16 and HPV 18 in spermatozoa and embryos of mice

Abstract Study question The clarification of Human Pappiloma Virus (HPV) internalization in spermatozoa and early preimplantation embryos. Summary answer Spermatozoa are able to internalize constructs of cloned high risk HPV viruses either as integrated or as episomal DNA. What is known already Human Pappiloma Virus (HPV) is a non-enveloped, circular, double stranded DNA virus. Persistent infection with oncogenic HPV genotypes triggers HPV DNA integration into the host genome, eventually leading to chromosomal damage accumulation and genome destabilization in infected cells. Living spermatozoa of almost all species are able to take up spontaneously exogenous DNA and internalize a part of it into their nucleus. Study design, size, duration Taking into account the capability of sperm cells to integrate exogenous DNA into their genome, we sought to clarify HPV internalization into sperm genome. A total of 26 sperm samples were studied. The control group included 97 embryos. As for the HPV 16 and HPV 18 group, a total of 89 embryos were studied. Participants/materials, setting, methods Sperm was incubated with plasmid vectors containing the complete genome of human HPV 16 and HPV 18 tagged with the green fluorescent protein (GFP) gene, to investigate HPV 16 and HPV 18 integration in mouse spermatozoa. Oocytes were in vitro fertilized with preincubated spermatozoa to investigate HPV 16 and HPV 18 potential transfer to mouse embryos. Main results and the role of chance Spermatozoa were able to internalize constructs of cloned high-risk HPV either as integrated or as episomal DNA. Constructs of cloned HPV can also be transferred to mouse embryos, through in vitro fertilization of the oocytes by mouse spermatozoa. Limitations, reasons for caution Viral DNA integration into the sperm nucleus could not be directly demonstrated, but nevertheless integration is evident by GFP gene expression. Wider implications of the findings This study highlights the possibility of viral DNA transmission to the early embryo via sperm, opening new perspectives on the effect of HPV in reproductive cells. HPV persistence may impair sperm parameters, suggesting caution in the use of these cells for assisted reproduction techniques or sperm banking. Trial registration number Not applicable