Activation of CD4+ T cells, increased TH2-type cytokine mRNA expression, and eosinophil recruitment in bronchoalveolar lavage after allergen inhalation challenge in patients with atopic asthma

J Allergy Clin Immunol. 1993 Aug;92(2):313-24. doi: 10.1016/0091-6749(93)90175-f.


Background: We have examined whether the local eosinophilia provoked by inhalational allergen challenge of patients with atopic asthma is associated with the appearance, in vivo, of activated TH2-type T helper lymphocytes.

Methods: Fifteen patients with atopic asthma had bronchial wash and bronchoalveolar lavage (BAL) 24 hours after allergen or diluent challenge separated by at least 21 days.

Results: There was an increase in eosinophils in both bronchial wash (p = 0.01) and BAL (p = 0.02) after allergen challenge but not after diluent challenge. Activation of CD4+ BAL T cells was suggested by an increase in the expression of CD25 shown by flow cytometry after allergen challenge, when compared with diluent (p = 0.02). There was no evidence of activation of CD8 T cells. By in situ hybridization after allergen challenge as compared with diluent, increases were shown in the numbers of cells expressing mRNA for interleukin-4 (IL-4) (p = 0.005), IL-5 (p = 0.01), and granulocyte-macrophage colony-stimulating factor (p = 0.03) but not IL-3, IL-2, or interferon-gamma. In situ hybridization of BAL cells after immunomagnetic separation of CD2-positive and CD2-negative cell populations showed that IL-4 and IL-5 mRNAs were associated with T lymphocytes after allergen challenge. BAL and bronchial wash eosinophilia closely correlated with maximal late fall in forced expiratory volume in 1 second after allergen challenge.

Conclusion: Cytokines produced by activated TH2-type CD4+ T cells in the airway may contribute to late asthmatic responses by mechanisms that include eosinophil accumulation.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Adult
  • Allergens / immunology*
  • Asthma / etiology
  • Asthma / immunology*
  • Asthma / metabolism
  • Bronchoalveolar Lavage Fluid / cytology
  • CD4 Antigens / analysis*
  • Cytokines / genetics
  • Cytokines / metabolism*
  • Eosinophils / physiology*
  • Female
  • Flow Cytometry
  • Humans
  • Hypersensitivity / complications
  • In Situ Hybridization
  • Interleukins / genetics
  • Lymphocyte Activation*
  • Male
  • RNA, Messenger / metabolism
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism


  • Allergens
  • CD4 Antigens
  • Cytokines
  • Interleukins
  • RNA, Messenger