Structural evaluation of new human polyomaviruses provides clues to pathobiology

摘要

In the past three years remarkable discoveries have added three new human polyomaviruses (KIV, WUV and MCV) to a class that previously had two disease-causing members (BKV and JCV). Two monkey polyomaviruses, simian virus 40 (SV40) and B-cell lymphotropic polyomavirus (LPV) are also present in humans. KIV and WUV lack the agnoprotein coding sequence and regulatory microRNA clusters of BKV, JCV and SV40. MCV lacks the agnoprotein sequence but generates microRNAs. KIV, WUV and MCV are all widespread in humans. Although they have distinctive tissue tropisms, they are all likely acquired in childhood. Of these viruses, only MCV has thus far been strongly linked to cancer. Marshalled evidence from diverse sources implicates MCV as an etiological agent of Merkel cell carcinoma. This review compares structural features of the new and previously-known polyomaviruses with the aim of identifying approaches to molecular pathology.