Hypersensitivity reactions after respiratory sensitization: effect of intranasal peptides containing T-cell epitopes.

Abstract

BACKGROUND:

The intranasal administration of peptides containing T-cell epitopes has been shown to inhibit T-cell and antibody responses of mice injected with allergen, but responses to respiratory sensitization might be regulated differently.

OBJECTIVE:

This study was designed to examine the effect of intranasal peptide on antigen-induced lung inflammatory responses and delayed hypersensitivity after sensitization by the respiratory mucosa or without sensitization.

METHODS:

Mice were treated with an intranasal tolerizing regimen of a peptide containing the major T-cell epitope of Der p 1. Delayed hypersensitivity and lung inflammation to challenge with Der p 1 was measured either without further treatment or after sensitization induced by means of the intranasal administration of Der p 1 with a mutated enterotoxin adjuvant. Lung inflammatory responses were examined by means of lavage and histologic section, and delayed hypersensitivity responses were measured on the basis of ear swelling.

RESULTS:

Delayed hypersensitivity reactions were induced in mice treated with intranasal peptide, and large reactions were found in mice given intranasal peptide and sensitized with intranasal Der p 1 and adjuvant. Mice pretreated with peptide and sensitized with Der p 1 had an increased lymphocytic infiltration after allergen-specific challenge, as measured by means of bronchoalveolar lavage and shown histologically. These hypersensitivity results are in contrast to previous data that show tolerance to injected antigen.

CONCLUSIONS:

Although the intranasal administration of a peptide containing a T-cell epitope markedly inhibits responses to sensitization produced by the injection of allergen, the peptide induces immune responses and increases hypersensitivity to respiratory sensitization.

• Authors: Andrew G Jarnicki, Takao Tsuji, Wayne R Thomas
• Journal: The Journal of allergy and clinical immunology (J Allergy Clin Immunol) Vol. 110 Issue 4 Pg. 610-6 (Oct 2002) ISSN: 0091-6749 [Print] United States
• PMID: 12373270 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Allergens
• Antigens, Dermatophagoides
• Epitopes
• Glycoproteins
• Peptides

Topics

• Administration, Intranasal
• Allergens (immunology)
• Animals
• Antibody Formation
• Antigens, Dermatophagoides
• Bronchoalveolar Lavage Fluid (cytology)
• Epitopes (chemistry)
• Glycoproteins (immunology)
• Hypersensitivity, Delayed (immunology, pathology)
• Immunization
• Lymphocytes (pathology)
• Mice
• Mice, Inbred C57BL
• Peptides (administration & dosage, chemistry, pharmacology)
• Pneumonia (immunology, pathology)
• Respiratory Hypersensitivity (immunology, pathology, physiopathology)
• T-Lymphocytes (immunology)