Increased levels of a TH2-type CC chemokine thymus and activation-regulated chemokine (TARC) in serum and induced sputum of asthmatics

Abstract

8 B~A ~ Increased Levels of a TH2-Type CC Chemokine Thymus and ~p-lr Activation-Regulated Chemokine (TARC) in Serum and Induced Sputum of Asthmatics Takashi Sekiya*, Hirokazu Yamada*, Masao Yamaguchi*, Akira lshii*, Kazuhiko Yamamoto*, Atsushi Morita§, Yasuyuki Sano¥ Osamu Yoshie~, Kouji Matsushima*, Koichi Hirai* *University of Tokyo, Tokyo, Japan §Shionogi Institute for Medical Science, Osaka, Japan ~q)oai Memorial Hospital, Tokyo, Japan ~Kinki University, Osaka, Japan BACKGROUND: Cytokines liberated by Th2 cells play a crucial role in the pathogenesis of bronchial asthma. Recent studies have demonstrated that CC chemokine receptor (CCR)4 is preferentially expressed in Th2 cells. These facts suggest the possible involvement of both of CCR4-specific ligands, i.e., thymus and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC), in pathogenesis of bronchial asthma via recruitment of Th2 cells at inflammatory sites. We explored the levels of TARC and MDC in serum and induced sputum of asthmatics. METHODS: Levels of TARC in serum (46 asthmatics and 26 normal individuals) and induced sputa (30 asthmatics and 6 normal individuals) were measured by a high-sensitive ELISA system. Levels of eotaxin and MDC were also measured by ELISA. RESULTS: TARC but not MDC was significantly increased in asthmatic sera (p<0.001). Although MDC was undetectable in the sputum of most of cases by our system, sputum TARC was significantly increased (p=0.027). CONCLUSIONS: The elevated TARC levels in asthmatics might contribute to the pathophysiology of asthma.