title: The correlation between IL-20 and the Th2 immune response in human asthma.
abstract: Interleukin-20 (IL-20) belongs to the IL-10 family, which has been shown to be crucial in immune responses, regulation of inflammatory responses, hemopoiesis, and epidermal cell and keratinocyte differentiation. However, the role of IL-20 in asthma remains unclear. Here, our aim is to evaluate the correlation between IL-20 and the Th2 immune response in human.
  
  
  
  In this study, we recruited 100 asthma patients and 100 control subjects for collection of serum samples and biopsy material. Firstly, We observed the expression of IL-20 in the airway epithelium of asthma patients by immuno-histochemical analysis, and then used an enzyme-linked immune-sorbent assay (ELISA) to analyze the serum levels of IL-20, IL-4, IL-5 and IL-13 in patients with asthma.
  
  
  
  We found high levels of expression of IL-20 in the airway epithelium of asthma patients. We also found that the concentrations of IL-20 and the Th2 cytokines, IL-4, IL-5 and IL-13, were significantly higher in patients with asthma and a positive correlation were found between IL-20 and Th2 cytokines (IL-4, IL-5, and IL-13). Furthermore, levels of IL-20 gradually increased according to the severity of the asthma.
  
  
  
  IL-20 levels are increased in the epithelium and serum of asthmatic patients. The correlation between IL-20 levels and Th2 cytokines suggests that IL-20 may play a patho-physiologic role in the Th2 immune response in human asthma and may be a potential biomarker of asthma severity.
authors.affiliation: Department of Respiratory, Qilu Hospital of Shangdong University, Jinan, Shandong, 250012,China.
authors.forename: Jinxiang
authors.initials: J
authors.lastname: Wu
authors.forename: Guicheng
authors.initials: G
authors.lastname: Wang
authors.forename: Junqing
authors.initials: J
authors.lastname: Hao
authors.forename: Wenbin
authors.initials: W
authors.lastname: Gong
mesh_terms: D000328:Adult; D001249:Asthma / Q000276:immunology*; D015415:Biomarkers / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007378:Interleukins / Q000096:biosynthesis / Q000276:immunology*; D008297:Male; D018418:Th2 Cells / Q000276:immunology*
chemical_list: D015415:Biomarkers; D007378:Interleukins; C422042:interleukin 20