title: HTLV-1-associated inflammatory myopathies: low proviral load and moderate inflammation in 13 patients from West Indies and West Africa.
abstract: BACKGROUND
  The Human T-cell Leukemia Virus type 1 (HTLV-1) is the causative agent of several inflammatory diseases, including HTLV-1-associated inflammatory myopathies (HAIM). Little is known about the virological and immunological characteristics of this viral disease.
  
  
  OBJECTIVE
  To characterize the histological and virological features of HAIM patients, in order to better understand the pathogenetic mechanisms and unravel new biological markers of this disease.
  
  
  METHODS
  We conducted a retrospective study on 13 patients with HAIM, based on blood and muscle samples. We included blood samples from HTLV-1-infected individuals without myopathy as controls. Muscle biopsies were used for a broad immunohistological evaluation of tissue damage and inflammation, as well as identification of infected cells through in situ hybridization. DNA extracted from patients' PBMC was used to identify the virus genotype by sequencing and to assess the proviral load by quantitative PCR. Anti-viral antibodies in plasma samples were titrated by indirect immunofluorescence.
  
  
  RESULTS
  Patients originate from HTLV-1 endemic areas, the West Indies and West Africa. Histological alterations and inflammation in patients muscles were mostly moderate, with classical features of idiopathic myositis and rare HTLV-1-infected infiltrating cells. In all patients, HTLV-1 belonged to the A subtype, transcontinental subgroup. Anti-HTLV-1 antibodies titers were high, but the proviral load was not elevated compared to asymptomatic HTLV-1 carriers.
  
  
  CONCLUSIONS
  We show here that muscle inflammation is moderate in HAIM, and accompanied by a low HTLV-1 proviral load, suggesting that the pathogenetic events do not exactly mirror those of other HTLV-1-associated inflammatory diseases.
authors: Institut Pasteur, 75015 Paris, France.
authors: Marion
authors: M
authors: Desdouits
authors: Olivier
authors: O
authors: Cassar
authors: Thierry
authors: T
authors: Maisonobe
authors: Alexandra
authors: A
authors: Desrames
authors: Achille
authors: A
authors: Aouba
authors: Olivier
authors: O
authors: Hermine
authors: Jacqueline
authors: J
authors: Mikol
authors: Marc
authors: M
authors: Polivka
authors: Isabelle
authors: I
authors: Penisson-Besnier
authors: Pascale
authors: P
authors: Marcorelles
authors: Fabien
authors: F
authors: Zagnoli
authors: Thomas
authors: T
authors: Papo
authors: Arnaud
authors: A
authors: Lacour
authors: Zahir
authors: Z
authors: Amoura
authors: Julien
authors: J
authors: Haroche
authors: Patrick
authors: P
authors: Cherin
authors: Antonio
authors: A
authors: Teixeira
authors: Olivier
authors: O
authors: Benveniste
authors: Serge
authors: S
authors: Herson
authors: Anne-Sophie
authors: AS
authors: Morin
authors: Franck
authors: F
authors: Mortreux
authors: Eric
authors: E
authors: Wattel
authors: Michel
authors: M
authors: Huerre
authors: Marie-Christine
authors: MC
authors: Cumont
authors: Sandra
authors: S
authors: Martin-Latil
authors: Gillian
authors: G
authors: Butler-Browne
authors: Olivier
authors: O
authors: Gout
authors: Graham
authors: G
authors: Taylor
authors: Antoine
authors: A
authors: Gessain
authors: Simona
authors: S
authors: Ozden
authors: Pierre-Emmanuel
authors: PE
authors: Ceccaldi
mesh_terms: D000328:Adult; D000354:Africa, Western; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D015490:HTLV-I Infections / Q000821:virology*; D015368:Human T-lymphotropic virus 1 / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007249:Inflammation / Q000821:virology*; D008297:Male; D008875:Middle Aged; D009220:Myositis / Q000821:virology*; D010802:Phylogeny; D011533:Proviruses / Q000302:isolation & purification; D012333:RNA, Messenger / Q000032:analysis; D012367:RNA, Viral / Q000032:analysis; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D019562:Viral Load; D014900:West Indies
chemical_list: D012333:RNA, Messenger; D012367:RNA, Viral