title: HLA-B27-mediated protection in HIV and hepatitis C virus infection and pathogenesis in spondyloarthritis: two sides of the same coin?
abstract: OBJECTIVE
  HLA-B27 is associated with low viral load and long-term nonprogression in HIV infection as well as spontaneous clearance of hepatitis C virus (HCV) infection. This review summarizes mechanisms that have been suggested to be involved in this protective effect of HLA-B27, and highlights possible lessons for the role of HLA-B27 in spondyloarthritis.
  
  
  RESULTS
  Recent studies linked protection by HLA-B27 in HIV and HCV infection to virological mechanisms such as a complicated pathways of viral escape from immunodominant HLA-B27-restricted virus-specific CD8+ T-cell epitopes. In addition, several immunological mechanisms have been proposed, including CD8+ T-cell polyfunctionality and functional avidity, thymic selection of CD8+ T-cell precursors, specific T-cell receptor repertoires and clonotypes, efficient antigen processing, and evasion from regulatory T-cell-mediated suppression.
  
  
  CONCLUSIONS
  Multiple virological and immunological mechanisms have been suggested to contribute to HLA-B27-mediated protection in HIV and HCV infection. Some of these mechanisms may also be involved in HLA-B27-associated pathogenesis in spondyloarthritis.
authors: Department of Medicine II, Freiburg University Medical Center, University of Freiburg, Freiburg, Germany. christoph.neumann-haefelin@uniklinik-freiburg.de
authors: Christoph
authors: C
authors: Neumann-Haefelin
mesh_terms: D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D018450:Disease Progression; D015658:HIV Infections / Q000276:immunology* / Q000821:virology; D020276:HIV Long-Term Survivors; D015796:HLA-B27 Antigen / Q000235:genetics / Q000276:immunology*; D006526:Hepatitis C / Q000276:immunology* / Q000821:virology; D006801:Humans; D016056:Immunodominant Epitopes / Q000276:immunology; D025241:Spondylarthritis / Q000235:genetics / Q000276:immunology*; D019562:Viral Load / Q000276:immunology
chemical_list: D015796:HLA-B27 Antigen; D016056:Immunodominant Epitopes