title: Frequent detection of Merkel cell polyomavirus DNA in sera of HIV-1-positive patients.
abstract: BACKGROUND
  Merkel cell polyomavirus (MCPyV), human polyomavirus-6 (HPyV6), and human polyomavirus-7 (HPyV7) were identified as viruses shed from the skin. Serological analysis revealed that these viruses are common among the general population. However, there is little information about the presence of MCPyV, HPyV6, and HPyV7 in the sera and tissues of immunocompromised individuals. The aims of this study are to know if immune status affects the presence of MCPyV, HPyV6, and HPyV7 in the serum, and to reveal the presence of these viruses in diseased tissues of unknown etiology.
  
  
  METHODS
  Sera from HIV-1-positive and -negative patients were examined by real-time PCR and nested PCR detecting MCPyV, HPyV6 and HPyV7. In addition, diseased tissue samples of unknown etiology were examined.
  
  
  RESULTS
  Nine out of 23 serum samples (39.1%) from HIV-1-positive patients who had not received anti-retroviral therapy were positive for MCPyV, which is significantly higher than HIV-1-negative patients (6/110, 5.5%, P<0.01, Chi-square test). MCPyV DNA was detected in tissue samples of Merkel cell carcinoma (22/30 [73%]), encephalitis (4/19 [21%]), pneumonia (3/17 [18%]), and myocarditis (8/14 [57%]). With the exception of Merkel cell carcinoma samples, MCPyV-positive tissues showed low copy numbers of MCPyV DNA by real-time PCR and no expression of the MCPyV large T antigen by immunohistochemistry. HPyV6 and HPyV7 were rarely detected in serum and tissue samples.
  
  
  CONCLUSIONS
  These results suggest that MCPyV viremia is associated with host immunity, and that circulation of HPyV6 and HPyV7 in the serum is rare.
authors.affiliation: Department of Pathology, National Institute of Infectious Diseases, Shinjuku, Tokyo, 162-8640, Japan.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Fukumoto
authors.forename: Yuko
authors.initials: Y
authors.lastname: Sato
authors.forename: Hideki
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Harutaka
authors.initials: H
authors.lastname: Katano
mesh_terms: D000914:Antibodies, Viral / Q000276:immunology; D004279:DNA, Viral / Q000097:blood* / Q000235:genetics; D015658:HIV Infections / Q000097:blood* / Q000150:complications / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000502:physiology; D006801:Humans; D059965:Merkel cell polyomavirus / Q000235:genetics / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D027601:Polyomavirus Infections / Q000150:complications / Q000276:immunology / Q000821:virology*; D014412:Tumor Virus Infections / Q000150:complications / Q000276:immunology / Q000821:virology*
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral