Survival of Eosinophils Isolated from Nasal Polyps.

Asthma, nasal allergy and nasal polyposis are diseases of respiratory tract characterized by chronic inflammation in which the accumulation of activated eosinophils in the tissue is a prevalent feature. To elucidate the role of eosinophils in the pathogenesis of these diseases, we isolated eosinophils directly from nasal polyp tissues. This time, purity of eosinophils after isolation was 80.0±9.2% and 98% of these eosinophils were EG2 positive which indicates activated eosinophils. Then, we also examined the survival of these eosinophils. Our data show that thespontaneous (unstimulated) survival ex vivo of such in vivo activated eosinophils was enhanced as compared to that of peripheral blood eosinophils from healthy subjects. This enhanced survival of tissue eosinophils must be the part of the mechanism of eosinophil accumulation in the tissues.