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A1319 - An Effect of Clarthromycin Treatment in HDM-Induced Allergic Airway Inflammation in Mice
Author Block: K. Takahashi, H. Sadamatsu, H. Tashiro, G. Kato, M. Uchida, S. Kimura, N. Sueoka-Aragane; Saga University Faculty of Medicine, Saga, Japan.
Rationale; Severe asthma has several phenotypes including type2 and non-type2 inflammation. Molecular targeted agents were used in type2 severe asthma, while there is no specific treatment for non-type2 asthma. Clarthromycin (CAM) has not only anti-bacterial activity but also anti-inflammatory effect. The aim of this study is to clarify an effect and mechanism of CAM treatment in HDM-induced airway inflammation in mice. Methods; Balb/c mice were intranasally sensitized and challenged by house dust mite (HDM), and they were orally administered with CAM in five days per week for three weeks. They were divided into 3 groups (PBS-placebo, HDM-placebo and HDM-CAM). Blood, bronchoalveolar lavage fluid (BALF) and lung tissue were harvested after 24 hours from final challenge. Airway inflammation was assessed using inflammatory cells in BAL. Cytokines were examined by ELISA in lung tissue. Results; The number of cells in BAL of HDM-placebo mice was significantly higher than PBS-placebo mice (PBS-placebo; 1.82±0.07×104/ml vs HDM-placebo; 52.28±16.53×104/ml). The number of total cells, neutrophils and eosinophils of HDM-CAM mice were lower than HDM-placebo mice in BAL (total cells: HDM-CAM; 31.07±6.79×104/ml, neutrophils: HDM-placebo; 15.14±6.45×104/ml vs HDM-CAM; 7.18±1.96×104/ml, eosinophils: HDM-placebo; 21.77±6.49×104/ml vs HDM-CAM; 11.73±3.59×104/ml). The concentrations of IL-13 and MIP2 in lung of HDM-CAM mice were lower than HDM-placebo mice (IL-13: HDM-placebo; 543.5±144.4 pg/ml vs HDM-CAM; 407.4±105.9 pg/ml, MIP2: HDM-placebo; 187.9±35.9 pg/ml vs HDM-CAM; 147.3±48.4 pg/ml). Conclusions; CAM attenuated both type2 and non-type2 airway inflammation in HDM-induced allergic airway inflammation.