History of Discoveries and Pathogenicity of TT Viruses

  • H. OkamotoEmail author
Part of the Current Topics in Microbiology and Immunology book series (CT MICROBIOLOGY, volume 331)


Since 1997, groups of novel nonenveloped DNA viruses with a circular, single-stranded (negative sense) DNA genome of 3.6–3.9 kb, 3.2 kb, or 2.8–2.9 kb in size have been discovered and designated Torque teno virus (TTV), Torque teno midi virus (TTMDV), and Torque teno mini virus (TTMV), respectively, in the floating genus Anellovirus . These three anelloviruses frequently and ubiquitously infect humans, and the infections are characterized by lifelong viremia and great genetic variability. Although TTV infection has been epidemiologically suggested to be associated with many diseases including liver diseases, respiratory disorders, hematological disorders, and cancer, there is no direct causal evidence for links between TTV infection and specific clinical diseases. The pathogenetic role of TTMV and TTMDV infections remains unknown. The changing ratio of the three anelloviruses to each other over time, relative viral load, or combination of different genotype(s) of each anellovirus may be associated with the pathogenicity or the disease-inducing potential of these three human anelloviruses. To clarify their disease association, polymerase chain reaction (PCR) systems for accurately detecting, differentiating, and quantitating all of the genotypes and/or genogroups of TTV, TTMDV, and TTMV should be established and standardized, as should methods to detect past infections and immunological responses to anellovirus infections.


Idiopathic Pulmonary Fibrosis Polymerase Chain Reaction Assay Torque Teno Virus Chicken Anemia Virus Torque Teno Mini Virus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Akiba J, Umemura T, Alter HJ, et al (2005) SEN virus: epidemiology and characteristics of a transfusion-transmitted virus. Transfusion 45:1084–1088PubMedGoogle Scholar
  2. Andreoli E, Maggi F, Pistello M, et al (2006) Small anellovirus in hepatitis C patients and healthy controls. Emerg Infect Dis 12:1175–1176PubMedGoogle Scholar
  3. Bando M, Ohno S, Oshikawa K, et al (2001) Infection of TT virus in patients with idiopathic pulmonary fibrosis. Respir Med 95:935–942PubMedGoogle Scholar
  4. Bando M, Takahashi M, Ohno S, et al (2008) Torque teno virus DNA titre elevated in idiopathic pulmonary fibrosis with primary lung cancer. Respirology 13:263–269PubMedGoogle Scholar
  5. Barril G, Lopez-Alcorocho JM, Bajo A, et al (2000) Prevalence of TT virus in serum and peripheral mononuclear cells from a CAPD population. Perit Dial Int 20:65–68PubMedGoogle Scholar
  6. Biagini P, Gallian P, Attoui H, et al (2001a) Comparison of systems performance for TT virus detection using PCR primer sets located in non-coding and coding regions of the viral genome. J Clin Virol 22:91–99Google Scholar
  7. Biagini P, Gallian P, Attoui H, et al (2001b) Genetic analysis of full-length genomes and subgenomic sequences of TT virus-like mini virus human isolates. J Gen Virol 82:379–383Google Scholar
  8. Biagini P, Charrel RN, de Micco P, et al (2003) Association of TT virus primary infection with rhinitis in a newborn. Clin Infect Dis 36:128–129PubMedGoogle Scholar
  9. Biagini P, Todd D, Bendinelli M, et al (2005) Anellovirus. In: Fauquet CM, Mayo MA, Maniloff J, Desselberger U, Ball LA (eds) Virus taxonomy: classification and nomenclature of viruses, eight report of the international committee on taxonomy of viruses. Elsevier/Academic Press, London, pp 335–341Google Scholar
  10. Biagini P, de Micco P, de Lamballerie X (2006a) Identification of a third member of the Anellovirus genus (“small anellovirus”) in French blood donors. Arch Virol 151:405–408Google Scholar
  11. Biagini P, Gallian P, Cantaloube JF, et al (2006b) Distribution and genetic analysis of TTV and TTMV major phylogenetic groups in French blood donors. J Med Virol 78:298–304Google Scholar
  12. Biagini P, Uch R, Belhouchet M, et al (2007) Circular genomes related to anelloviruses identified in human and animal samples by using a combined rolling-circle amplification/sequence-independent single primer amplification approach. J Gen Virol 88:2696–2701PubMedGoogle Scholar
  13. Brown KE, Tisdale J, Barrett AJ, et al (1997) Hepatitis-associated aplastic anemia. N Engl J Med 336:1059–1064PubMedGoogle Scholar
  14. Charlton M, Adjei P, Poterucha J, et al (1998) TT-virus infection in North American blood donors, patients with fulminant hepatic failure, and cryptogenic cirrhosis. Hepatology 28:839–842PubMedGoogle Scholar
  15. Christensen JK, Eugen-Olsen J, SLrensen M, et al (2000) Prevalence and prognostic significance of infection with TT virus in patients infected with human immunodeficiency virus. J Infect Dis 181:1796–1799PubMedGoogle Scholar
  16. Chung JY, Han TH, Koo JW, et al (2007) Small anellovirus infections in Korean children. Emerg Infect Dis 13:791–793PubMedGoogle Scholar
  17. de Villiers EM, Schmidt R, Delius H, et al (2002) Heterogeneity of TT virus related sequences isolated from human tumour biopsy specimens. J Mol Med 80:44–50PubMedGoogle Scholar
  18. Deng X, Terunuma H, Handema R, et al (2000) Higher prevalence and viral load of TT virus in saliva than in the corresponding serum: another possible transmission route and replication site of TT virus. J Med Virol 62:531–537PubMedGoogle Scholar
  19. Fanci R, De Santis R, Zakrzewska K, et al (2004) Presence of TT virus DNA in bone marrow cells from hematologic patients. New Microbiol 27:113–117PubMedGoogle Scholar
  20. Fornai C, Maggi F, Vatteroni ML, et al (2001) High prevalence of TT virus (TTV) and TTV-like minivirus in cervical swabs. J Clin Microbiol 39:2022–2024PubMedGoogle Scholar
  21. Foschini MP, Morandi L, Macchia S, et al (2001) TT virus-related acute recurrent hepatitis. Histological features of a case and review of the literature. Virchows Arch 439:752–755PubMedGoogle Scholar
  22. Gallian P, Biagini P, Zhong S, et al (2000) TT virus: a study of molecular epidemiology and transmission of genotypes 1, 2 and 3. J Clin Virol 17:43–49PubMedGoogle Scholar
  23. Garbuglia AR, Iezzi T, Capobianchi MR, et al (2003) Detection of TT virus in lymph node biopsies of B-cell lymphoma and Hodgkin's disease, and its association with EBV infection. Int J Immunopathol Pharmacol 16:109–118PubMedGoogle Scholar
  24. Gerner P, Oettinger R, Gerner W, et al (2000) Mother-to-infant transmission of TT virus: prevalence, extent and mechanism of vertical transmission. Pediatr Infect Dis J 19:1074–1077PubMedGoogle Scholar
  25. Griffiths P (1999) Time to consider the concept of a commensal virus? Rev Med Virol 9:73–74PubMedGoogle Scholar
  26. Hallett RL, Clewley JP, Bobet F, et al (2000) Characterization of a highly divergent TT virus genome. J Gen Virol 81:2273–2279PubMedGoogle Scholar
  27. Handa A, Dickstein B, Young NS, et al (2000) Prevalence of the newly described human circovirus, TTV, in United States blood donors. Transfusion 40:245–251PubMedGoogle Scholar
  28. Hijikata M, Iwata K, Ohta Y, et al (1999a) Genotypes of TT virus (TTV) compared between liver disease patients and healthy individuals using a new PCR system capable of differentiating 1a and 1b types from others. Arch Virol 144:2345–2354Google Scholar
  29. Hijikata M, Takahashi K, Mishiro S (1999b) Complete circular DNA genome of a TT virus variant (isolate name SANBAN) and 44 partial ORF2 sequences implicating a great degree of diversity beyond genotypes. Virology 260:17–22Google Scholar
  30. Hsieh SY, Wu YH, Ho YP, et al (1999) High prevalence of TT virus infection in healthy children and adults and in patients with liver disease in Taiwan. J Clin Microbiol 37:1829–1831PubMedGoogle Scholar
  31. Hu YW, Al-Moslih MI, Al Ali MT, et al (2005) Molecular detection method for all known genotypes of TT virus (TTV) and TTV-like viruses in thalassemia patients and healthy individuals. J Clin Microbiol 43:3747–3754PubMedGoogle Scholar
  32. Ikeda H, Takasu M, Inoue K, et al (1999) Infection with an unenveloped DNA virus (TTV) in patients with acute or chronic liver disease of unknown etiology and in those positive for hepatitis C virus RNA. J Hepatol 30:205–212PubMedGoogle Scholar
  33. Ishikawa T, Hamano Y, Okamoto H (1999) Frequent detection of TT virus in throat swabs of pediatric patients. Infection 27:298PubMedGoogle Scholar
  34. Itoh K, Takahashi M, Ukita M, et al (1999) Influence of primers on the detection of TT virus DNA by polymerase chain reaction. J Infect Dis 180:1750–1751PubMedGoogle Scholar
  35. Itoh Y, Takahashi M, Fukuda M, et al (2000) Visualization of TT virus particles recovered from the sera and feces of infected humans. Biochem Biophys Res Commun 279:718–724PubMedGoogle Scholar
  36. Jelcic I, Hotz-Wagenblatt A, Hunziker A, et al (2004) Isolation of multiple TT virus genotypes from spleen biopsy tissue from a Hodgkin's disease patient: genome reorganization and diversity in the hypervariable region. J Virol 78:7498–7507PubMedGoogle Scholar
  37. Jones MS, Kapoor A, Lukashov VV, et al (2005) New DNA viruses identified in patients with acute viral infection syndrome. J Virol 79:8230–8236PubMedGoogle Scholar
  38. Kakkola L, Kaipio N, Hokynar K, et al (2004) Genoprevalence in human tissues of TT-virus genotype 6. Arch Virol 149:1095–1106PubMedGoogle Scholar
  39. Kakkola L, Tommiska J, Boele LC, et al (2007) Construction and biological activity of a full-length molecular clone of human Torque teno virus (TTV) genotype 6. FEBS J 274:4719–4730PubMedGoogle Scholar
  40. Kamahora T, Hino S, Miyata H (2000) Three spliced mRNAs of TT virus transcribed from a plasmid containing the entire genome in COS1 cells. J Virol 74:9980–9986PubMedGoogle Scholar
  41. Kanda T, Yokosuka O, Ikeuchi T, et al (1999) The role of TT virus infection in acute viral hepatitis. Hepatology 29:1905–1908PubMedGoogle Scholar
  42. Kao JH, Chen W, Chen PJ, et al (2002) Prevalence and implication of a newly identified infectious agent (SEN virus) in Taiwan. J Infect Dis 185:389–392PubMedGoogle Scholar
  43. Kazi A, Miyata H, Kurokawa K, et al (2000) High frequency of postnatal transmission of TT virus in infancy. Arch Virol 145:535–540PubMedGoogle Scholar
  44. Khudyakov YE, Cong ME, Nichols B, et al (2000) Sequence heterogeneity of TT virus and closely related viruses. J Virol 74:2990–3000PubMedGoogle Scholar
  45. Kikuchi K, Miyakawa H, Abe K, et al (2000) Indirect evidence of TTV replication in bone marrow cells, but not in hepatocytes, of a subacute hepatitis/aplastic anemia patient. J Med Virol 61:165–170PubMedGoogle Scholar
  46. Leppik L, Gunst K, Lehtinen M, et al (2007) In vivo and in vitro intragenomic rearrangement of TT viruses. J Virol 81:9346–9356PubMedGoogle Scholar
  47. Lin HH, Kao JH, Lee PI, Chen DS (2002) Early acquisition of TT virus in infants: possible minor role of maternal transmission. J Med Virol 66:285–290PubMedGoogle Scholar
  48. Lisitsyn N, Lisitsyn N, Wigler M (1993) Cloning the differences between two complex genomes. Science 259:946–951PubMedGoogle Scholar
  49. Lopez-Alcorocho JM, Mariscal LF, de Lucas S, et al (2000) Presence of TTV DNA in serum, liver and peripheral blood mononuclear cells from patients with chronic hepatitis. J Viral Hepat 7:440–447PubMedGoogle Scholar
  50. Luo K, Liang W, He H, et al (2000) Experimental infection of nonenveloped DNA virus (TTV) in rhesus monkey. J Med Virol 61:159–164PubMedGoogle Scholar
  51. Maggi F, Fornai C, Zaccaro L, et al (2001a) TT virus (TTV) loads associated with different peripheral blood cell types and evidence for TTV replication in activated mononuclear cells. J Med Virol 64:190–194Google Scholar
  52. Maggi F, Pistello M, Vatteroni M, et al (2001b) Dynamics of persistent TT virus infection, as determined in patients treated with alpha interferon for concomitant hepatitis C virus infection. J Virol 75:11999–12004Google Scholar
  53. Maggi F, Marchi S, Fornai C, et al (2003a) Relationship of TT virus and Helicobacter pylori infections in gastric tissues of patients with gastritis. J Med Virol 71:160–165Google Scholar
  54. Maggi F, Pifferi M, Fornai C, et al (2003b) TT virus in the nasal secretions of children with acute respiratory diseases: relations to viremia and disease severity. J Virol 77:2418–2425Google Scholar
  55. Maggi F, Pifferi M, Tempestini E, et al (2003c) TT virus loads and lymphocyte subpopulations in children with acute respiratory diseases. J Virol 77:9081–9083Google Scholar
  56. Maggi F, Andreoli E, Riente L, et al (2007) Torquetenovirus in patients with arthritis. Rheumatology (Oxford) 46:885–886Google Scholar
  57. Miyamoto M, Takahashi H, Sakata I, et al (2000) Hepatitis-associated aplastic anemia and transfusion-transmitted virus infection. Intern Med 39:1068–1070PubMedGoogle Scholar
  58. Miyata H, Tsunoda H, Kazi A, et al (1999) Identification of a novel GC-rich 113-nucleotide region to complete the circular, single-stranded DNA genome of TT virus, the first human circovirus. J Virol 73:3582–3586PubMedGoogle Scholar
  59. Moen EM, Huang L, Grinde B (2002) Molecular epidemiology of TTV-like mini virus in Norway. Arch Virol 147:181–185PubMedGoogle Scholar
  60. Moriyama M, Matsumura H, Shimizu T, et al (2001) Histopathologic impact of TT virus infection on the liver of type C chronic hepatitis and liver cirrhosis in Japan. J Med Virol 64:74–81PubMedGoogle Scholar
  61. Muljono DH, Nishizawa T, Tsuda F, et al (2001) Molecular epidemiology of TT virus (TTV) and characterization of two novel TTV genotypes in Indonesia. Arch Virol 146:1249–1266PubMedGoogle Scholar
  62. Mushahwar IK, Erker JC, Muerhoff AS, et al (1999) Molecular and biophysical characterization of TT virus: evidence for a new virus family infecting humans. Proc Natl Acad Sci U S A 96:3177–3182PubMedGoogle Scholar
  63. Nakagawa N, Ikoma J, Ishihara T, et al (2000) Biliary excretion of TT virus (TTV). J Med Virol 61:462–467PubMedGoogle Scholar
  64. Naoumov NV, Petrova EP, Thomas MG, et al (1998) Presence of a newly described human DNA virus (TTV) in patients with liver disease. Lancet 352:195–197PubMedGoogle Scholar
  65. Niel C, Lampe E (2001) High detection rates of TTV-like mini virus sequences in sera from Brazilian blood donors. J Med Virol 65:199–205PubMedGoogle Scholar
  66. Niel C, de Oliveira JM, Ross RS, et al (1999) High prevalence of TT virus infection in Brazilian blood donors. J Med Virol 57:259–263PubMedGoogle Scholar
  67. Ninomiya M, Nishizawa T, Takahashi M, et al (2007a) Identification and genomic characterization of a novel human torque teno virus of 3.2 kb. J Gen Virol 88:1939–1944Google Scholar
  68. Ninomiya M, Takahashi M, Shimosegawa T, et al (2007b) Analysis of the entire genomes of fifteen torque teno midi virus variants classifiable into a third group of genus Anellovirus. Arch Virol 152:1961–1975Google Scholar
  69. Ninomiya M, Takahashi M, Nishizawa T, et al (2008) Development of PCR assays with nested primers specific for differential detection of three human anelloviruses and early acquisition of dual or triple infection during infancy. J Clin Microbiol 46:507–514PubMedGoogle Scholar
  70. Nishizawa T, Okamoto H, Konishi K, et al (1997) A novel DNA virus (TTV) associated with elevated transaminase levels in posttransfusion hepatitis of unknown etiology. Biochem Biophys Res Commun 241:92–97PubMedGoogle Scholar
  71. Ohbayashi H, Tanaka Y, Ohoka S, et al (2001) TT virus is shown in the liver by in situ hybridization with a PCR-generated probe from the serum TTV-DNA. J Gastroenterol Hepatol 16:424–428PubMedGoogle Scholar
  72. Okamoto H, Akahane Y, Ukita M, et al (1998a) Fecal excretion of a nonenveloped DNA virus (TTV) associated with posttransfusion non-A-G hepatitis. J Med Virol 56:128–132Google Scholar
  73. Okamoto H, Nishizawa T, Kato N, et al (1998b) Molecular cloning and characterization of a novel DNA virus (TTV) associated with posttransfusion hepatitis of unknown etiology. Hepatol Res 10:1–16Google Scholar
  74. Okamoto H, Kato N, Iizuka H, et al (1999a) Distinct genotypes of a nonenveloped DNA virus associated with posttransfusion non-A to G hepatitis (TT virus) in plasma and peripheral blood mononuclear cells. J Med Virol 57:252–258Google Scholar
  75. Okamoto H, Nishizawa T, Ukita M (1999b) A novel unenveloped DNA virus (TT virus) associated with acute and chronic non-A to G hepatitis. Intervirology 42:196–204Google Scholar
  76. Okamoto H, Nishizawa T, Ukita M, et al (1999c) The entire nucleotide sequence of a TT virus isolate from the United States (TUS01): comparison with reported isolates and phylogenetic analysis. Virology 259:437–448Google Scholar
  77. Okamoto H, Takahashi M, Nishizawa T, et al (1999d) Marked genomic heterogeneity and frequent mixed infection of TT virus demonstrated by PCR with primers from coding and noncoding regions. Virology 259:428–436Google Scholar
  78. Okamoto H, Nishizawa T, Tawara A, et al (2000a) Species-specific TT viruses in humans and nonhuman primates and their phylogenetic relatedness. Virology 277:368–378Google Scholar
  79. Okamoto H, Nishizawa T, Tawara A, et al (2000b) TT virus mRNAs detected in the bone marrow cells from an infected individual. Biochem Biophys Res Commun 279:700–707Google Scholar
  80. Okamoto H, Takahashi M, Kato N, et al (2000c) Sequestration of TT virus of restricted genotypes in peripheral blood mononuclear cells. J Virol 74:10236–10239Google Scholar
  81. Okamoto H, Takahashi M, Nishizawa T, et al (2000d) Replicative forms of TT virus DNA in bone marrow cells. Biochem Biophys Res Commun 270:657–662Google Scholar
  82. Okamoto H, Ukita M, Nishizawa T, et al (2000e) Circular double-stranded forms of TT virus DNA in the liver. J Virol 74:5161–5167Google Scholar
  83. Okamoto H, Nishizawa T, Takahashi M, et al (2001) Heterogeneous distribution of TT virus of distinct genotypes in multiple tissues from infected humans. Virology 288:358–368PubMedGoogle Scholar
  84. Okamoto H, Nishizawa T, Takahashi M (2004) Torque teno virus (TTV): molecular virology and clinical implications. In: Mushahwar IK (ed) Viral hepatitis: molecular biology, diagnosis, epidemiology and control. Elsevier, AmsterdamGoogle Scholar
  85. Okamura A, Yoshioka M, Kubota M, et al (1999) Detection of a novel DNA virus (TTV) sequence in peripheral blood mononuclear cells. J Med Virol 58:174–177PubMedGoogle Scholar
  86. Okamura A, Yoshioka M, Kikuta H, et al (2000) Detection of TT virus sequences in children with liver disease of unknown etiology. J Med Virol 62:104–108PubMedGoogle Scholar
  87. Ott C, Duret L, Chemin I, et al (2000) Use of a TT virus ORF1 recombinant protein to detect anti-TT virus antibodies in human sera. J Gen Virol 81:2949–2958PubMedGoogle Scholar
  88. Peng YH, Nishizawa T, Takahashi M, et al (2002) Analysis of the entire genomes of thirteen TT virus variants classifiable into the fourth and fifth genetic groups, isolated from viremic infants. Arch Virol 147:21–41PubMedGoogle Scholar
  89. Pifferi M, Maggi F, Andreoli E, et al (2005) Associations between nasal torquetenovirus load and spirometric indices in children with asthma. J Infect Dis 192:1141–1148PubMedGoogle Scholar
  90. Pifferi M, Maggi F, Caramella D, et al (2006) High torquetenovirus loads are correlated with bronchiectasis and peripheral airflow limitation in children. Pediatr Infect Dis J 25:804–808PubMedGoogle Scholar
  91. Pistello M, Morrica A, Maggi F, et al (2001) TT virus levels in the plasma of infected individuals with different hepatic and extrahepatic pathology. J Med Virol 63:189–195PubMedGoogle Scholar
  92. Poovorawan Y, Tangkijvanich P, Theamboonlers A, et al (2001) Transfusion transmissible virus TTV and its putative role in the etiology of liver disease. Hepatogastroenterology 48:256–260PubMedGoogle Scholar
  93. Prati D, Lin YH, De Mattei C, et al (1999) A prospective study on TT virus infection in transfusion-dependent patients with beta-thalassemia. Blood 93:1502–1505PubMedGoogle Scholar
  94. Rodríguez-Iñigo E, Casqueiro M, Bartolomé J, et al (2000) Detection of TT virus DNA in liver biopsies by in situ hybridization. Am J Pathol 156:1227–1234PubMedGoogle Scholar
  95. Safadi R, Or R, Ilan Y, et al (2001) Lack of known hepatitis virus in hepatitis-associated aplastic anemia and outcome after bone marrow transplantation. Bone Marrow Transplant 27:183–190PubMedGoogle Scholar
  96. Saitou N, Nei M (1987) The neighbor-joining method: a new method for reconstructing phylogenetic trees. Mol Biol Evol 4:406–425PubMedGoogle Scholar
  97. Schroter M, Laufs R, Zollner B, et al (2003) A novel DNA virus (SEN) among patients on maintenance hemodialysis: prevalence and clinical importance. J Clin Virol 27:69–73PubMedGoogle Scholar
  98. Shibata M, Morizane T, Baba T, et al (2000) TT virus infection in patients with fulminant hepatic failure. Am J Gastroenterol 95:3602–3606PubMedGoogle Scholar
  99. Shibayama T, Masuda G, Ajisawa A, et al (2001) Inverse relationship between the titre of TT virus DNA and the CD4 cell count in patients infected with HIV. Aids 15:563–570PubMedGoogle Scholar
  100. Simmonds P, Prescott LE, Logue C, et al (1999) TT virus—part of the normal human flora? J Infect Dis 180:1748–1750PubMedGoogle Scholar
  101. Sugiyama K, Goto K, Ando T, et al (2000) TT virus infection in Japanese children: isolates from genotype 1 are overrepresented in patients with hepatic dysfunction of unknown etiology. Tohoku J Exp Med 191:233–239PubMedGoogle Scholar
  102. Szladek G, Juhasz A, Kardos G, et al (2005) High co-prevalence of genogroup 1 TT virus and human papillomavirus is associated with poor clinical outcome of laryngeal carcinoma. J Clin Pathol 58:402–405PubMedGoogle Scholar
  103. Tajiri H, Tanaka T, Sawada A, et al (2001) Three cases with TT virus infection and idiopathic neonatal hepatitis. Intervirology 44:364–369PubMedGoogle Scholar
  104. Takahashi K, Hijikata M, Samokhvalov EI, et al (2000a) Full or near full length nucleotide sequences of TT virus variants (Types SANBAN and YONBAN) and the TT virus-like mini virus. Intervirology 43:119–123Google Scholar
  105. Takahashi K, Iwasa Y, Hijikata M, et al (2000b) Identification of a new human DNA virus (TTV- like mini virus, TLMV) intermediately related to TT virus and chicken anemia virus. Arch Virol 145:979–993Google Scholar
  106. Takahashi M, Asabe S, Gotanda Y, et al (2002) TT virus is distributed in various leukocyte sub-populations at distinct levels, with the highest viral load in granulocytes. Biochem Biophys Res Commun 290:242–248PubMedGoogle Scholar
  107. Takayama S, Miura T, Matsuo S, et al (1999) Prevalence and persistence of a novel DNA TT virus (TTV) infection in Japanese haemophiliacs. Br J Haematol 104:626–629PubMedGoogle Scholar
  108. Tanaka H, Okamoto H, Luengrojanakul P, et al (1998) Infection with an unenveloped DNA virus (TTV) associated with posttransfusion non-A to G hepatitis in hepatitis patients and healthy blood donors in Thailand. J Med Virol 56:234–238PubMedGoogle Scholar
  109. Tanaka Y, Hayashi J, Ariyama I, et al (2000) Seroepidemiology of TT virus infection and relationship between genotype and liver damage. Dig Dis Sci 45:2214–2220PubMedGoogle Scholar
  110. Tanaka Y, Primi D, Wang RY, et al (2001) Genomic and molecular evolutionary analysis of a newly identified infectious agent (SEN virus) and its relationship to the TT virus family. J Infect Dis 183:359–367PubMedGoogle Scholar
  111. Tawara A, Akahane Y, Takahashi M, et al (2000) Transmission of human TT virus of genotype 1a to chimpanzees with fecal supernatant or serum from patients with acute TTV infection. Biochem Biophys Res Commun 278:470–476PubMedGoogle Scholar
  112. Thom K, Petrik J (2007) Progression towards AIDS leads to increased Torque teno virus and Torque teno minivirus titers in tissues of HIV infected individuals. J Med Virol 79:1–7PubMedGoogle Scholar
  113. Thom K, Morrison C, Lewis JC, et al (2003) Distribution of TT virus (TTV), TTV-like minivirus, and related viruses in humans and nonhuman primates. Virology 306:324–333PubMedGoogle Scholar
  114. Tokita H, Murai S, Kamitsukasa H, et al (2002a) TT virus of certain genotypes may reduce the platelet count in patients who achieve a sustained virologic response to interferon treatment for chronic hepatitis C. Hepatol Res 23:105–114Google Scholar
  115. Tokita H, Murai S, Kamitsukasa H, et al (2002b) High TT virus load as an independent factor associated with the occurrence of hepatocellular carcinoma among patients with hepatitis C virus-related chronic liver disease. J Med Virol 67:501–509Google Scholar
  116. Touinssi M, Gallian P, Biagini P, et al (2001) TT virus infection: prevalence of elevated viraemia and arguments for the immune control of viral load. J Clin Virol 21:135–141PubMedGoogle Scholar
  117. Toyoda H, Naruse M, Yokozaki S, et al (1999) Prevalence of infection with TT virus (TTV), a novel DNA virus, in healthy Japanese subjects, newborn infants, cord blood and breast milk. J Infect 38:198–199PubMedGoogle Scholar
  118. Tsuda F, Okamoto H, Ukita M, et al (1999) Determination of antibodies to TT virus (TTV) and application to blood donors and patients with post-transfusion non-A to G hepatitis in Japan. J Virol Methods 77:199–206PubMedGoogle Scholar
  119. Tuveri R, Jaffredo F, Lunel F, et al (2000) Impact of TT virus infection in acute and chronic, viral- and non viral-related liver diseases. J Hepatol 33:121–127PubMedGoogle Scholar
  120. Ukita M, Okamoto H, Kato N, et al (1999) Excretion into bile of a novel unenveloped DNA virus (TT virus) associated with acute and chronic non-A-G hepatitis. J Infect Dis 179:1245–1248PubMedGoogle Scholar
  121. Ukita M, Okamoto H, Nishizawa T, et al (2000) The entire nucleotide sequences of two distinct TT virus (TTV) isolates (TJN01 and TJN02) remotely related to the original TTV isolates. Arch Virol 145:1543–1559PubMedGoogle Scholar
  122. Umemura T, Yeo AE, Sottini A, et al (2001) SEN virus infection and its relationship to transfusion-associated hepatitis. Hepatology 33:1303–1311PubMedGoogle Scholar
  123. Vasconcelos HC, Cataldo M, Niel C (2002) Mixed infections of adults and children with multiple TTV-like mini virus isolates. J Med Virol 68:291–298PubMedGoogle Scholar
  124. Viazov S, Ross RS, Varenholz C, et al (1998) Lack of evidence for an association between TTV infection and severe liver disease. J Clin Virol 11:183–187PubMedGoogle Scholar
  125. Yokoyama H, Yasuda J, Okamoto H, et al (2002) Pathological changes of renal epithelial cells in mice transgenic for the TT virus ORF1 gene. J Gen Virol 83:141–150PubMedGoogle Scholar
  126. Zein NN, Arslan M, Li H, et al (1999) Clinical significance of TT virus infection in patients with chronic hepatitis C. Am J Gastroenterol 94:3020–3027PubMedGoogle Scholar
  127. Zhong S, Yeo W, Tang M, et al (2002) Frequent detection of the replicative form of TT virus DNA in peripheral blood mononuclear cells and bone marrow cells in cancer patients. J Med Virol 66:428–434PubMedGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  1. 1.Division of Virology, Department of Infection and ImmunityJichi Medical University School of MedicineShimotsuke-ShiJapan

Personalised recommendations