Expression of mRNA for RANTES in human eosinophils

RANTES has been considered to play an important role in various immune and allergic disorders since RANTES is a potent chemoattractant for various important inflammatory cells such as eosinophils. Eosinophils, on the other hand, are considered to be the major inflammatory cells in bronchial asthma since eosinophil-specific granule proteins can damage bronchial mucosal cells. The recent demonstration that eosinophils themselves could synthesize some cytokines such as IL-5 indicates the role of these cytokines not only in paracrine but also in autocrine regulation of eosinophil production, differentiation and activation. Therefore, in this study, we examined mRNA for RANTES and release of RANTES by human eosinophils. The present findings revealed that eosinophils obtained from asthmatic patients could express and release RANTES. Taken together, these findings suggest that eosinophils play a crucial role in the pathogenesis, particularly in eosinophil and T lymphocyte recruitment into the inflamed sites in asthma through RANTES production.