Human T-cell epitopes of the latex allergen Hev b 5 in health care workers

• Published in: Journal of allergy and clinical immunology 2000-05, Vol.105 (5), p.1017-1024
• Main Authors: de Silva, Harini D., Sutherland, Michael F., Suphioglu, Cenk, McLellan, Susan C., Slater, Jay E., Rolland, Jennifer M., O’Hehir, Robyn E.
• Format: Article
• Language: English
• Subjects: Adult; Aged; allergen; Allergens - immunology; Allergic diseases; allergy; Antigens, Plant; Biological and medical sciences; Epitope Mapping; Epitopes, T-Lymphocyte; Female; Health Personnel; Hev b 5; Hev b 5 antigen; Humans; hypersensitivity; Immunoglobulin E - blood; Immunopathology; Interferon-gamma - metabolism; Interleukin-5 - metabolism; Latex; Latex Hypersensitivity; Medical sciences; Middle Aged; peptides; Plant Proteins; Skin allergic diseases. Stinging insect allergies; T cells; T-cell epitopes; T-Lymphocytes - immunology; T-Lymphocytes - metabolism
• ISSN: 0091-6749; 1097-6825
• DOI: 10.1067/mai.2000.105806

Background: Latex allergy affects health care workers as a high-risk cohort. Hev b 5 is a major latex allergen reacting with serum IgE from 92% of latex-allergic health care workers. Because CD4+ T-cell recognition is central to the specific immune response to allergens, identification of dominant T-cell epitopes is important for the development of specific immunotherapy for latex allergy. Objective: Our purpose was to map T-cell epitopes of Hev b 5 in health care workers. Methods: Six latex-allergic health care workers (grade 3 to 4 enzyme allergosorbent test score) were studied. Peripheral blood latex specific 3-week T-cell lines were generated and screened for proliferative response to overlapping 20-mer peptides of Hev b 5. Supernatants collected at 48 hours were analyzed by ELISA for IL-5 and IFN-γ. Results: Dot immunoblotting with use of recombinant Hev b 5/maltose-binding protein indicated serum-specific IgE in 5 of 6 patients. T-cell reactivity to one or more Hev b 5 peptides was identified in these 5 donors, but not in the sixth. Hev b 5 (46-65) induced T-cell proliferation in all 5 donors. Hev b 5 (109-128) stimulated T cells from 3 of these patients. Proliferative responses were accompanied by substantial IL-5 secretion and minimal IFN-γ, indicating a TH2-predominant cytokine profile. Conclusions: Five of 6 latex-allergic patients demonstrated T-cell responsiveness to Hev b 5 consistent with a major T-cell reactive latex allergen. Two T-cell immunodominant regions of Hev b 5 were identified, and reactivity to these sites was associated with strong IL-5 but minimal IFN-γ production. (J Allergy Clin Immunol 2000;105:1017-24.)