Depletion of circulating allergen-specific TH2 T lymphocytes after allergen exposure in asthma

J Allergy Clin Immunol. 1997 Jun;99(6 Pt 1):788-97. doi: 10.1016/s0091-6749(97)80013-9.


Background: In allergic asthma, CD4+ T lymphocytes are a fundamental component of local chronic inflammation. Their cytokine profile is oriented toward a TH2 phenotype, characterized by production of IL-4, IL-5, IL-10, and IL-13. Egress of T cells from blood to airways after allergen challenge has been described.

Objective: We have studied a cohort of six patients with asthma who had multiple allergies to investigate how exposure to allergen affects the proliferation of peripheral CD4+ T lymphocytes with different allergen specificities and lymphokine profiles.

Methods: For each patient, CD4+ T-cell lines were generated by in vitro stimulation with sensitizing and with nonsensitizing allergens, and IL-4 and interferon-gamma production by these lines was assessed. Proliferation of peripheral blood CD4+ T lymphocytes in response to the same allergens was measured before and 24 hours after inhalation challenge with a sensitizing allergen.

Results: We found that each single sensitizing allergen can deplete peripheral blood of TH2-type CD4+ T lymphocytes specific for all sensitizing allergens, but not of TH1-type CD4+ T lymphocytes.

Conclusions: Our results suggest the existence of mechanisms capable of sorting disease-associated antigen specificities together with defined lymphokine patterns into T lymphocytes that can migrate to target organs, in allergic asthma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Adult
  • Allergens / administration & dosage
  • Allergens / blood*
  • Allergens / immunology*
  • Animals
  • Asthma / immunology*
  • Cytokines / biosynthesis
  • Epitopes / immunology
  • Female
  • Humans
  • Lymphocyte Activation
  • Lymphocyte Depletion*
  • Male
  • Middle Aged
  • Mites / immunology
  • Poaceae / immunology
  • Th2 Cells / immunology*
  • Th2 Cells / metabolism


  • Allergens
  • Cytokines
  • Epitopes