title: Merkel cell polyomavirus and trichodysplasia spinulosa-associated polyomavirus DNAs and antibodies in blood among the elderly.
abstract: BACKGROUND
  Merkel cell polyomavirus (MCPyV) and trichodysplasia spinulosa-associated polyomavirus (TSPyV) are recently found pathogens causing two rare skin disorders, Merkel cell carcinoma (MCC) and trichodysplasia spinulosa (TS). MCC is proportionally common in the elderly and most often is associated with immunosuppression. TS is a folliculocentric infection seen in patients in an immunocompromised state. Little or no baseline information exists, however, on the prevalences of these two viruses among the elderly. Epidemiologic data on this population could help in understanding their natural biology. We wished to determine the occurrences and blood levels of MCPyV and TSPyV DNAs among the elderly and any association between the prevalences of their corresponding antiviral IgG antibodies.
  
  
  METHODS
  From 394 hospitalized elderly individuals (age ≥65 years) with respiratory symptoms, cardiovascular, and other diseases, we studied 621 serum samples by four different real-time quantitative (q) PCRs, two for the DNAs of MCPyV and two for TSPyV. The IgG antibodies for both viruses among 481 serum samples of 326 subjects were measured with enzyme immunoassays (EIAs), using as antigen recombinant virus-like particles (VLPs).
  
  
  RESULTS
  Of the 394 patients, 39 (9.9%) were positive at least once for MCPyV DNA by the LT PCR, and 33 (8.4%) by the VP1 PCR, while 6 (1.5%) were positive by both PCR assays. In general, the viral DNA copy numbers were low. In sharp contrast, no TSPyV DNA was detectable with qPCRs for the corresponding genomic regions. The IgG seroprevalence of MCPyV was 59.6% and of TSPyV, 67.3%.
  
  
  CONCLUSIONS
  MCPyV DNA, unlike TSPyV DNA, occurs in low copy number in serum samples from a notable proportion of aging individuals. Whether this reflects enhanced viral replication possibly due to waning immune surveillance, and is associated with increased MCC risk, deserves exploration.
authors.affiliation: Department of Virology, Haartman Institute, University of Helsinki, Helsinki, Finland. reza.sadeghi@helsinki.fi
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Sadeghi
authors.forename: Matti
authors.initials: M
authors.lastname: Aronen
authors.forename: Tingting
authors.initials: T
authors.lastname: Chen
authors.forename: Laura
authors.initials: L
authors.lastname: Jartti
authors.forename: Tuomas
authors.initials: T
authors.lastname: Jartti
authors.forename: Olli
authors.initials: O
authors.lastname: Ruuskanen
authors.forename: Maria
authors.initials: M
authors.lastname: Söderlund-Venermo
authors.forename: Klaus
authors.initials: K
authors.lastname: Hedman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood*; D004279:DNA, Viral / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D059965:Merkel cell polyomavirus / Q000235:genetics* / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral