title: Expansion of pathogen-specific mono- and multifunctional Th1 and Th17 cells in multi-focal tuberculous lymphadenitis.
abstract: BACKGROUND
  Th1 and Th17 responses are known to play an important role in immunity to pulmonary tuberculosis (PTB), although little is known about their role in extrapulmonary forms of tuberculosis (TB).
  
  
  METHODS
  To identify the role of Th1, Th17, and Th22 cells in multi-focal TB lymphadenitis (TBL), we examined mycobacteria-specific immune responses in the whole blood of individuals with PTB (n = 20) and compared them with those with TBL (n = 25).
  
  
  RESULTS
  Elevated frequencies of CD4(+) T cells expressing IFN- γ, TNF-α, and IL-2 were present in individuals with TBL compared with those with PTB at baseline and in response to ESAT-6 and CFP-10. Similarly, increased frequencies of CD4(+) T cells expressing IL-17A, IL-17F, and IFN-γ were also present in individuals with TBL at baseline and following ESAT-6 and CFP-10 stimulation although no significant difference in frequency of Th22 cells was observed. Finally, frequencies of Th1 (but not Th17) cells exhibited a significantly negative correlation with natural regulatory T cell frequencies at baseline.
  
  
  CONCLUSIONS
  Multi-focal TB lymphadenitis is therefore characterized by elevated frequencies of Th1 and Th17 cells, indicating that Th1 and Th17 responses in TB disease are probably correlates of disease severity rather than of protective immunity.
authors: National Institutes of Health-International Center for Excellence in Research, Chennai, India.
authors: Nathella Pavan
authors: NP
authors: Kumar
authors: Rathinam
authors: R
authors: Sridhar
authors: Vaithilingam V
authors: VV
authors: Banurekha
authors: Dina
authors: D
authors: Nair
authors: Mohideen S
authors: MS
authors: Jawahar
authors: Thomas B
authors: TB
authors: Nutman
authors: Subash
authors: S
authors: Babu
mesh_terms: D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018417:Th1 Cells / Q000276:immunology*; D058504:Th17 Cells / Q000276:immunology*; D014388:Tuberculosis, Lymph Node / Q000276:immunology* / Q000382:microbiology; D055815:Young Adult