title: Hypodense eosinophils in allergic rhinitis.
abstract: Based on density, function, and membrane receptors, peripheral blood eosinophils are a heterogeneous population of cells. Importantly, hypodense eosinophils (HE) are metabolically more active and likely to contribute to tissue injury. In the following study, peripheral blood from patients with allergic rhinitis (AR) was evaluated for the presence of HE. To accomplish this, blood was obtained from patients with ragweed AR, granulocytes were isolated and fractionated by continuous density Percoll gradients, and the density distribution of these cells was determined after centrifugation. A significantly higher percentage of peripheral blood eosinophils were hypodense (defined as density less than 1.081 gm/ml) in patients with AR when these patients were compared to control subjects, 30.0 +/- 5.0% versus 9.0 +/- 1.9%, p less than 0.01. Moreover, we also noted that an increased percentage of HE was found more often in patients with moderate-to-severe AR than in subjects with none-to-mild disease (p less than 0.01). These data suggest that the appearance of HE in the circulation may relate to the development of allergic symptoms. Furthermore, our observations suggest that the HE, because of its enhanced metabolic activity and now its association with more symptomatic hay fever, may participate in the pathophysiology of AR.
mesh_terms: D000328:Adult; D000397:Air Pollution; D002469:Cell Separation / Q000379:methods; D005260:Female; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D006801:Humans; D007958:Leukocyte Count; D008214:Lymphocytes / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D008297:Male; D011058:Pollen / Q000032:analysis; D006255:Rhinitis, Allergic, Seasonal / Q000097:blood* / Q000276:immunology
chemical_list: D006634:Histamine H1 Antagonists