Identification of the disease-related T cell epitope of ovalbumin and epitope-targeted T cell inactivation in egg allergy.
An ovalbumin (OVA)-specific T cell line (TCL) was established from a patient with hen egg allergy. The TCL was CD4+, expressed alpha beta T cell receptor, and recognized OVA presented by HLA-DR10. Based on the response of the TCL to synthetic OVA peptides, it was found that the TCL recognized OVA 323-339, which is a major T cell epitope presented by murine I-Ad. The TCL secreted high levels of IL-5, but undetectable amounts of IL-2, interferon-gamma, and IL-4 when stimulated with OVA or the OVA 323-339 peptide. Since IL-5 is an important growth and chemotactic factor for eosinophils, it is possible that these OVA 323-339-specific T cells can contribute to human egg allergy. To our knowledge, this is the first demonstration of food allergen-specific TCL establishment and identification of a T cell epitope possibly related to the allergic reaction to food antigens. An analog peptide of the OVA 323-339 which is known to strongly bind to I-Ad partially inhibited the response of the TCL to OVA 323-339 presented by HLA-DR10, raising the possibility of peptide-based immunotherapy of food allergy.
Shimojo
N
N
Department of Pediatrics, Chiba University School of Medicine, Japan.
Katsuki
T
T
Coligan
J E
JE
Nishimura
Y
Y
Sasazuki
T
T
Tsunoo
H
H
Sakamaki
T
T
Kohno
Y
Y
Niimi
H
H
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D002461:Cell Line, Transformed; D002645:Chickens / Q000276:immunology; D002675:Child, Preschool; D016207:Cytokines / Q000096:biosynthesis; D004529:Egg White / Q000009:adverse effects*; D000939:Epitopes / Q000276:immunology*; D005512:Food Hypersensitivity / Q000276:immunology*; D006681:HLA-D Antigens / Q000235:genetics; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D008969:Molecular Sequence Data; D010047:Ovalbumin / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D016207:Cytokines; D000939:Epitopes; D006681:HLA-D Antigens; D010047:Ovalbumin