title: The role of Vdelta2+T-cells in patients with active Mycobacterium tuberculosis infection and tuberculin anergy.
abstract: METHODS
  Tuberculosis (TB) is one of the most common major infectious diseases. In humans, acquired protective immunity to Mycobacterium tuberculosis depends on T-cells and involves multiple T-cell subsets; however, the pathways used by T-cells to restrict the growth of M. tuberculosis are poorly understood.
  
  
  OBJECTIVE
  To investigate the possible role of Vdelta2+T-cells and regulatory T-cells in the immune response to M. tuberculosis. As Vdelta2+T-cell function has been shown to be impaired in patients with M. tuberculosis infection, we investigated the percentage of perforin and Fas ligand (FasL) positive Vdelta2+T-cells and the possible role of activating and inhibitory natural killer (NK) cell receptors as well as that of regulatory T-cells in the control of tuberculin responsiveness.
  
  
  RESULTS
  Tuberculin-negative patients demonstrated decreased perforin expression and increased FasL expression, which could not be explained by dysregulation of NK cell receptor expression or altered regulatory T-cell function.
  
  
  CONCLUSIONS
  Altered cytotoxic capacity and apoptotic potential of Vdelta2+T-cells provide a plausible explanation for defective cellular immune functions in M. tuberculosis-infected anergic patients.
authors.affiliation: Department of Medical Microbiology and Immunology, Pecs University Medical School, Pecs, Hungary.
authors.forename: L
authors.initials: L
authors.lastname: Szereday
authors.forename: Z
authors.initials: Z
authors.lastname: Baliko
authors.forename: J
authors.initials: J
authors.lastname: Szekeres-Bartho
mesh_terms: D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D000943:Antigens, Differentiation / Q000378:metabolism; D060908:CTLA-4 Antigen; D003602:Cytotoxicity, Immunologic; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D008875:Middle Aged; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism; D014376:Tuberculosis / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human