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Role of interleukin‐5 in enhanced migration of eosinophils from airways of immunized guinea‐pigs
Author(s) -
Coéffier Eliane,
Joseph Danielle,
Vargaftig B. Boris
Publication year - 1994
Publication title -
british journal of pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.432
H-Index - 211
eISSN - 1476-5381
pISSN - 0007-1188
DOI - 10.1111/j.1476-5381.1994.tb17057.x
Subject(s) - ovalbumin , eosinophil , guinea pig , immunology , bronchoalveolar lavage , antigen , leukotriene , biology , medicine , endocrinology , lung , asthma
1 Platelet activating factor (PAF), leukotriene B 4 (LTB 4 ) and interleukin‐5 (IL‐5) are potent chemoatt‐ractants for guinea‐pig eosinophils, which may be involved in eosinophil recruitment and up‐regulation in allergic diseases. Eosinophils from the bronchoalveolar lavage fluid (BALF) of ovalbumin‐sensitized guinea‐pigs were collected 24 h after antigen provocation and migration induced by PAF, LTB 4 and rhIL‐5 was studied. 2 Total BALF content and distribution of eosinophils were greater in immunized, ovalbumin‐challenged guinea‐pigs (5.0 ± 0.8 × 10 6 /guinea‐pig; 12 ± 1%) than in immunized, saline‐challenged animals (3.0 ± 0.7 × 10 6 /guinea‐pig; 7 ± 1%). 3 The chemoattraction of eosinophils isolated on a metrizamide gradient was studied in micro‐Boyden chambers, results being expressed as the number of migrating cells (mean ± s.e.mean). PAF and LTB 4 ‐induced migration of eosinophils from immunized and OA‐challenged guinea‐pigs were significantly enhanced, as compared to immunized and saline‐challenged animals (170 ± 36 vs 35 ± 9 migrating eosinophils for 10 n m PAF; 271 ± 60 vs 110 ± 19 for 1 n m LTB 4 ). 4 The IL‐5 antibody TRFK‐5, in vivo , reduced eosinophil recruitment in BALF of antigen‐challenged immunized animals as well as the enhanced responsiveness of eosinophils from the challenged animals, suggesting a role for IL‐5 in the priming of eosinophils in vivo . 5 In contrast to TRFK‐5, nedocromil sodium reduced to a similar extent eosinophil, macrophage and lymphocyte recruitment into the BALF of antigen‐challenged, but failed to down‐regulate the enhanced responsiveness of eosinophils from the challenged animals. 6 The increased eosinophil content in lungs from antigen‐challenged guinea‐pigs is thus selectively reduced by the anti‐IL‐5 antibody, which also attenuates the concomitant enhancement of the eosinophil responsiveness, supporting the concept that IL‐5 is essential for recruitment and priming of eosinophils in vivo . In contrast, nedocromil sodium reduced non‐selectively the total cell recruitment to the airways, but failed to attenuate the enhanced responsiveness of those eosinophils which migrated, indicating that its effects involve a different target.