title: Reduced IL-12 level correlates with decreased IFN-gamma secreting T cells but not natural killer cell activity in asthmatic children.
abstract: BACKGROUND
  Accessory cells such as macrophages and natural killer cells, and their cytokines such as IL-10, IL-12, and IFN-gamma have been suggested to play a critical role in the development of T helper cells.
  
  
  OBJECTIVE
  Both natural killer cells and peripheral blood mononuclear cells were isolated and stimulated for their ability in producing cytokines. In addition, the percentage of IFN-gamma-secreting cells was analyzed with the method of intracellular staining.
  
  
  RESULTS
  The data suggested (1) no significant difference between asthmatic children and normal controls in number, cytotoxicity, and IFN-gamma production of purified NK cells; (2) decreased secretion of IL-12 by stimulated peripheral blood mononuclear cells in asthmatic children compared with normals (P < .05); (3) decreased production of IFN-gamma by PBMC from asthmatic children compared with normals (P < .05); and (4) intracellular expressed IFN-gamma level was lower in CD4+ T cells of asthmatic children (P < .05).
  
  
  CONCLUSIONS
  The results suggested that IL-12 produced predominantly by macrophages and associated decreased IFN-gamma-secreting CD4+ T cells play a critical role in the pathogenesis of asthma.
authors.affiliation: Department of Pediatrics, College of Medicine, National Taiwan University, Taipei, ROC.
authors.forename: C C
authors.initials: CC
authors.lastname: Chou
authors.forename: M S
authors.initials: MS
authors.lastname: Huang
authors.forename: K H
authors.initials: KH
authors.lastname: Hsieh
authors.forename: B L
authors.initials: BL
authors.lastname: Chiang
mesh_terms: D001249:Asthma / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism*; D018664:Interleukin-12 / Q000378:metabolism*; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D018655:Lymphocyte Count; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis; D016176:T-Lymphocyte Subsets / Q000378:metabolism; D013601:T-Lymphocytes / Q000378:metabolism*; D018417:Th1 Cells / Q000378:metabolism; D018418:Th2 Cells / Q000378:metabolism
chemical_list: D015375:Receptors, Interleukin-2; D018664:Interleukin-12; D007371:Interferon-gamma