title: Expansions of CD4+CD28- and CD8+CD28- T cells in granulomatosis with polyangiitis and microscopic polyangiitis are associated with cytomegalovirus infection but not with disease activity.
abstract: OBJECTIVE
  T helper cells lacking CD28 (CD4+CD28-) have been implicated in the pathogenesis of granulomatosis with polyangiitis (Wegener; GPA) and microscopic polyangiitis (MPA). Expansions of CD4+CD28- and CD8+CD28- T cells have also been associated with latent cytomegalovirus (CMV) infection. We assessed these T cells with and without coexpression of CD56 and CD57 in relation to vasculitis as well as CMV status.
  
  
  METHODS
  Blood from 16 patients in remission (12 GPA, 4 MPA), 18 patients with active vasculitis (12 GPA, 6 MPA), and 20 healthy controls was examined by flow cytometry for expression of CD4, CD8, CD56, CD57, and CD28 on T cells. The influence of age, CMV status, presence of disease, and disease activity on T cell subpopulations was tested with multiple regression analyses.
  
  
  RESULTS
  In active vasculitis, the total numbers and proportion of lymphocytes were decreased. Total numbers of CD4+, CD8+, CD4+CD28-, CD8+CD28-, CD4+CD57+, and CD8+CD57+ T subpopulations were decreased to the same extent, implying unchanged proportions. Multivariate analyses showed no associations between vasculitis and CD28- or CD57+ T subpopulations, whereas immunoglobulin G antibodies to CMV were associated with expanded proportions of CD28- and CD57+ T cells, in both the CD4+ and the CD8+ compartments.
  
  
  CONCLUSIONS
  CD28- and CD57+ T cells were associated with latent CMV infection and not with a diagnosis of GPA or MPA. Vasculitis assessment should include CMV status.
authors: Department of Rheumatology, University Hospital, and Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, 581 85 Linköping, Sweden. per.eriksson@lio.se
authors: Per
authors: P
authors: Eriksson
authors: Christina
authors: C
authors: Sandell
authors: Karin
authors: K
authors: Backteman
authors: Jan
authors: J
authors: Ernerudh
mesh_terms: D000368:Aged; D018106:CD28 Antigens / Q000378:metabolism*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000821:virology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000821:virology; D003587:Cytomegalovirus / Q000276:immunology; D003586:Cytomegalovirus Infections / Q000150:complications / Q000276:immunology* / Q000821:virology; D005260:Female; D014890:Granulomatosis with Polyangiitis / Q000150:complications / Q000276:immunology* / Q000821:virology; D006801:Humans; D008297:Male; D055953:Microscopic Polyangiitis / Q000150:complications / Q000276:immunology* / Q000821:virology; D008875:Middle Aged; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D018106:CD28 Antigens