Expression Of Toll-like Receptor 2 On Macrophages Of Induced Sputum In Chronic Cough And Effect Of Methylprednisolone

Object:To explore the relationship between the expression of the Toll-like receptor 2 on macrophages of induced sputum in chronic cough with airway inflammation and the effect of methylprednisolone. Methods:40 outpatients with chronic cough were collected from the respiratory department in the Affiliated Hospital of Luzhou Medical Colleage from June 2009 to March 2010 by anatomic diagnostic procedure. In the 40 cases, 15 cases were cough variant asthma(CVA),6 cases were upper airway cough syndrome(UACS),8 cases were eosinophilic bronchitis(EB) and 11 cases were gastroesophageal reflux cough(GERC).10 healthy volunteers were control group. Induced sputum were collected by aerosol inhalation of 3%-5% sodium chloride. The sputum differential cell counts were determined by HE staining. Adherent method was used to separate and cultivate macrophages which were divided into two groups. One group was not added methylprednisolone, another group was added methylprednisolone at a 400μg/ml and continued to cultivate. Immunofluorescence staining was performed to observe the expression of TLR2 and the effect of methylprednisolone on it. The concentration of Interleukine-8(IL-8) and the tumor necrosis factor-a(TNF-a) in the supermatant of induced sputum was measured with enzyme linked immunosorbent assay(ELISA). Date was analyzed with SPSS13.0. Results were expressed as the mean±tandard deviation(x±s). q test was adopted in the comparison between the groups, Linear correlation was adopted in the correlation analysis. Differences were considered significant at the P<0.05 level. Results:1. The total inflammatory cell number in induced sputum among the patients with cough variant asthma(CVA), upper airway cough syndrome(UACS), eosinophilic bronchitis(EB), and gastroesophageal reflux cough(GERC) group trended to increased, with decreased macrophage and increased neutrophil differential in comparision with the control group(P<0.05). The difference between two groups were no significant(P>0.05). The counts of eosinophils were significantly increased in the induced sputum of CVA and EB group in comparision with other groups. The difference between the two groups were no significant(P>0.05).2. The concentration of IL-8 and TNF-a in the supermatant of induced sputum of CVA, UACS, EB and GERC group was significantly increased in comparision with the control group(P<0.05).3. The concentration of IL-8 in the supermatant of induced sputum of CVA, UACS, EB and GERC group was positively correlated with neutrophil (R=0.628,0.816,0.769 and 0.733 respectively, P=0.012,0.048,0.026, and 0.016 respectively). The concentration of TNF-a in the supermatant of induced sputum of CVA, UACS, EB and GERC group was positively correlated with neutrophil(R=0.579,0.865,0.730 and 0.755 respectively, P=0.024,0.026,0.040 and 0.012 respectively).4. The expression of TLR2 on macrophages of induced sputum in chronic cough was significantly decreased in comparision with the control group; The expression of TLR2 was up-regulated by methylprednisolone. Conclusions: 1.The different cause of chronic cough patient has the heterogeneity the airway inflammation. There is eosinophilic airway inflammation in CVA and EB and neutrophilic airway inflammation in UACS and GERC.2. The expression of TLR2 on macrophages of induced sputum in CVA、UACS、EB and GERC was decreased, which might result in persistent airway inflammation. The expression of TLR2 on macrophages of induced sputum was up-regulated by methylprednisolone.