Eosinophil recruitment is associated with IL-5, but not with RANTES, twenty-four hours after allergen challenge.
Several lines of evidence suggest that the chemokine RANTES may play a role in eosinophilia observed during allergic inflammation. To test this hypothesis, six patients with allergic asthma were studied. After performing bronchoalveolar lavage in a lung segment (baseline), segmental bronchoprovocation was performed with saline solution in another segment and with ragweed in a third segment. Bronchoalveolar lavage was performed 24 hours later in the saline-challenged (sham) and ragweed-challenged lung segments. The bronchoalveolar lavage fluids from the baseline, sham, and ragweed segments were analyzed for cell counts and for the levels of IL-5, RANTES, and eosinophil-derived neurotoxin. IL-5 levels were elevated in the ragweed (984 +/- 588 pg/ml) compared with sham segments (2.8 +/- 0.2 pg/ml, p = 0.02). Likewise, RANTES levels were elevated in the ragweed (12.93 +/- 3.4 pg/ml) compared with the sham segments (3.05 +/- 1.19 pg/ml, p = 0.006). The IL-5 levels correlated with both eosinophil numbers (r = 0.90, p < 0.02) and eosinophil-derived neurotoxin levels (r = 0.89, p < 0.02). In contrast, RANTES levels did not correlate with either eosinophil numbers or eosinophil-derived neurotoxin levels. These results indicate that although both IL-5 and RANTES are elevated 24 hours after allergen challenge, only IL-5 correlates with eosinophil recruitment and degranulation.
Sur
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Department of Medicine, East Carolina University School of Medicine, Greenville, NC 27858, USA.
Kita
H
H
Gleich
G J
GJ
Chenier
T C
TC
Hunt
L W
LW
D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000276:immunology*; D001249:Asthma / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology; D015550:Cell Degranulation; D018946:Chemokine CCL5 / Q000502:physiology*; D002634:Chemotaxis, Leukocyte; D004804:Eosinophils / Q000276:immunology*; D005260:Female; D006801:Humans; D015848:Interleukin-5 / Q000502:physiology*; D007958:Leukocyte Count; D008297:Male; D013997:Time Factors
D000485:Allergens; D018946:Chemokine CCL5; D015848:Interleukin-5