title: Implication of Epstein-Barr virus infection in disease-specific autoreactive B cell activation in ectopic lymphoid structures of Sjögren's syndrome.
abstract: OBJECTIVE
  To examine whether the B cell tropic γ-herpesvirus Epstein-Barr virus (EBV) is aberrantly expressed in its latent and lytic forms within ectopic lymphoid structures (ELS) in the salivary glands of patients with Sjögren's syndrome (SS), and to investigate the relationship between EBV dysregulation, B cell activation, in situ differentiation of autoreactive plasma cells, disease-specific autoantibody production, and cytotoxicity.
  
  
  METHODS
  Latent and lytic EBV infection in the salivary glands of 28 patients with SS and 38 patients with nonspecific chronic sialadenitis (NSCS), characterized for the presence or absence of ELS, was investigated by reverse transcription-polymerase chain reaction, in situ hybridization, and immunohistochemical/immunofluorescence staining. Glandular versus synovial production of anti-Ro 52, anti-citrullinated protein antibodies (ACPAs), and anti-EBV peptide antibodies was analyzed in situ or in vivo in human SS/SCID and human rheumatoid arthritis/SCID mouse chimeras.
  
  
  RESULTS
  EBV dysregulation within inflammatory infiltrates was observed exclusively in ELS+ SS salivary gland tissue, as revealed by latent EBV infection and lytic EBV infection in B cells and plasma cells, respectively. Conversely, epithelial latent membrane protein 2A expression was observed in both patients with SS and patients with NSCS. Importantly, perifollicular plasma cells displaying Ro 52 immunoreactivity were frequently infected by EBV. Furthermore, ELS-containing SS salivary gland tissue that was transplanted into SCID mice supported the production of anti-Ro 52/anti-La 48 and anti-EBV antibodies but not ACPAs. Analysis of CD4+ and CD8+ T cell localization and granzyme B expression demonstrated that the persistence of EBV in ELS-containing SS salivary glands was associated with follicular exclusion of CD8+ T cells and impaired CD8-mediated cytotoxicity.
  
  
  CONCLUSIONS
  Active EBV infection is selectively associated with ELS in the salivary glands of patients with SS and appears to contribute to local growth and differentiation of disease-specific autoreactive B cells.
authors.affiliation: William Harvey Research Institute, Queen Mary University of London, London, UK.
authors.forename: Cristina
authors.initials: C
authors.lastname: Croia
authors.forename: Elisa
authors.initials: E
authors.lastname: Astorri
authors.forename: William
authors.initials: W
authors.lastname: Murray-Brown
authors.forename: Amanda
authors.initials: A
authors.lastname: Willis
authors.forename: Karl A
authors.initials: KA
authors.lastname: Brokstad
authors.forename: Nurhan
authors.initials: N
authors.lastname: Sutcliffe
authors.forename: Kim
authors.initials: K
authors.lastname: Piper
authors.forename: Roland
authors.initials: R
authors.lastname: Jonsson
authors.forename: Anwar R
authors.initials: AR
authors.lastname: Tappuni
authors.forename: Costantino
authors.initials: C
authors.lastname: Pitzalis
authors.forename: Michele
authors.initials: M
authors.lastname: Bombardieri
mesh_terms: D000328:Adult; D000368:Aged; D001402:B-Lymphocytes / Q000276:immunology*; D020031:Epstein-Barr Virus Infections / Q000276:immunology*; D005260:Female; D004854:Herpesvirus 4, Human / Q000302:isolation & purification*; D006801:Humans; D008221:Lymphoid Tissue / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012469:Salivary Glands / Q000276:immunology; D012793:Sialadenitis / Q000276:immunology / Q000821:virology; D012859:Sjogren's Syndrome / Q000276:immunology / Q000821:virology*