title: Increase in human endogenous retrovirus HERV-K (HML-2) viral load in active rheumatoid arthritis.
abstract: To study the viral loads of human endogenous retrovirus HERV-K (HML-2) type 1 and type 2 in rheumatoid arthritis (RA), we measured the viral loads of HERV-K (HML-2) type 1 and type 2 using nucleic acid sequence-based amplification (NASBA) technology. We analyzed plasma samples from RA patients (n = 79) and healthy volunteers (HV, n = 46) and synovial fluid samples from RA (n = 10) and osteoarthritis (OA, n = 10) patients. HERV-K type 1 and type 2 viruses were detected and quantified for the majority of plasma and synovial fluid samples from RA patients. HERV-K type 1 and type 2 viral loads were significantly elevated in RA patients compared with HV in plasma (P < 0.0001) and from RA patients compared with OA patients in synovial fluid (type 1: P = 0.0007; type 2: P = 0.023). Moreover, an association was observed between the HERV-K type 1 viral load in plasma and the disease activity in RA patients (RA patients with low activity versus high activity P = 0.0129; RA patients with intermediate activity versus high activity P = 0.037). Our findings showed that HERV-K (HML-2) viral load can be detected in plasma samples from RA patients, with higher levels observed for those with active disease. There was an association of HERV-K type 1 levels with the disease activity.
authors.affiliation: Joint Unit Hospices Civils de Lyon - bioMérieux, and Department of Immunology and Rheumatology, Immunogenomics and inflammation research Unit EA 4130, University of Lyon, Lyon, France.
authors.forename: F
authors.initials: F
authors.lastname: Reynier
authors.forename: T
authors.initials: T
authors.lastname: Verjat
authors.forename: F
authors.initials: F
authors.lastname: Turrel
authors.forename: P E
authors.initials: PE
authors.lastname: Imbert
authors.forename: H
authors.initials: H
authors.lastname: Marotte
authors.forename: B
authors.initials: B
authors.lastname: Mougin
authors.forename: P
authors.initials: P
authors.lastname: Miossec
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000821:virology*; D020077:Endogenous Retroviruses / Q000302:isolation & purification*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000097:blood / Q000821:virology*; D013582:Synovial Fluid / Q000821:virology*; D019562:Viral Load