RESUMO
<p><b>OBJECTIVE</b>To study the serum level of interleukin-17A (IL-17A) and its expressions in the lung, spleen and thymus in asthmatic mice.</p><p><b>METHODS</b>In 14 normal BALB/c female mice and 14 asthmatic mice, the changes in the airway pathology and the cell proportion in the bronchoalveolar lavage fluid (BALF) were observed. The serum level of IL-17A and IL-17A expressions in the tissue homogenates of the lung, spleen and thymus of the mice were detected by sandwich enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS</b>The airway inflammation in the asthmatic mice was characterized mainly by eosinophil and neutrophil infiltration, which was not observed in the normal control group. Serum IL-17A levels and IL-17A expressions in the lung, spleen and thymus of the asthmatic mice were significantly higher than those in the normal control group (P<0.01). In the asthmatic mice, IL-17A expression in the lung tissues was positively correlated with the percentages of neutrophils (r=0.693, P=0.040) and eosinophils (r=0.733, P=0.030) in the BALF.</p><p><b>CONCLUSION</b>IL-17A is highly expressed in the serum, lung, spleen and thymus of asthmatic mice. IL-17A may be one of the major cytokines involved in exacerbation of bronchial asthma, and is probably associated with the recruitment of neutrophils and eosinophils into the airways.</p>