title: Decrease in interleukin-21 in children suffering with severe atopic dermatitis.
abstract: BACKGROUND
  Atopic dermatitis (AD) is a kind of eczema with an inflammatory, relapsing, non-contagious, and pruritic skin disorder. It is associated with the local infiltration of T helper type 2 (Th2) cells that secrete interleukin (IL)-4 and IL-5. IL-21 is a member of IL-2 family cytokine mainly expressed by activated CD4+ T lymphocytes. Until now, there is no clinical research in the expression of IL-21 in patients with AD.
  
  
  METHODS
  We analyzed serum levels of total immunoglobulin E (IgE), allergen-specific IgE, and cytokines IL-4, IL-5, IFN-γ, IL-17, and IL-21 in AD cases and controls. In addition, cytokine levels in the culture supernatants of peripheral blood mononuclear cells stimulated with anti-CD3 and anti-CD28 Abs, phytohemagglutin (PHA), or pokeweed mitogen (PWM) were measured. We also assessed clinical skin severity by Scoring of Atopic Dermatitis (SCORAD) index.
  
  
  RESULTS
  Our results showed that serum total IgE in the case group was significantly higher than that of control group (365.449 ± 52.945 and 39.243 ± 7.605 IU/ml, respectively). Logistic regression analysis system reveals serum levels of IL-21 and IFN-γ are significantly correlated. However, IL-21 and IL-4, IL-21 and IL-5, as well as IL-21 and IL-17 showed no correlation.
  
  
  CONCLUSIONS
  A significantly decreased level of IL-21 was observed in children suffering with severe AD compared with controls, suggesting that IL-21 may play a role in AD.
authors: Department of Pediatrics, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan.
authors: Sheng-Chieh
authors: SC
authors: Lin
authors: Ya-Hui
authors: YH
authors: Chuang
authors: Yao-Hsu
authors: YH
authors: Yang
authors: Bor-Luen
authors: BL
authors: Chiang
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism; D018106:CD28 Antigens / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D003876:Dermatitis, Atopic / Q000097:blood / Q000276:immunology* / Q000503:physiopathology*; D018450:Disease Progression; D015536:Down-Regulation; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007371:Interferon-gamma / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D007378:Interleukins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008297:Male; D010835:Phytohemagglutinins / Q000276:immunology / Q000378:metabolism; D011043:Pokeweed Mitogens / Q000276:immunology / Q000378:metabolism; D018418:Th2 Cells / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D000098546:Interleukin-21
chemical_list: D000911:Antibodies, Monoclonal; D018106:CD28 Antigens; D017252:CD3 Complex; D007378:Interleukins; D010835:Phytohemagglutinins; D011043:Pokeweed Mitogens; D007073:Immunoglobulin E; D007371:Interferon-gamma; D000098546:Interleukin-21