Les polyomavirus humains : la famille s'agrandit…!!!

The first identified polyomaviruses were oncogenic viruses in animals, whereas the two historical human representatives within this family, the BK and JC viruses, were isolated later in immunocompromized patients. In the context of immunosuppression the BK virus (BKPyV) and the JC virus (JCPyV) may reactivate and cause serious illness known as polyomavirus-induced nephropathy and progressive multifocal leucoencephalopathy, respectively. In human, transforming and oncogenic capabilities of these viruses were often suspected but never clearly demonstrated. The recent use of high-throughput sequencing and improved metagenomic approaches have allowed for the identification of several new human polyomaviruses. One of the most striking achievements is the recent identification of the Merkel cell polyomavirus (MCPyV), primarily isolated and likely involved in an aggressive neuro-endocrine skin tumor, the Merkel cell carcinoma. However, several other human polyomaviruses were described in respiratory samples for the KI and WU polyomaviruses (KIPyV, WUPyV) and in cutaneous samples for the human polyomaviruses 6, 7 and 9 (HPyV6, HPyV7, HPyV9) and the Trichodysplasia Spinulosa-associated polyomavirus (TSPyV).