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


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-gamma, indicating a T(H)2-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-gamma production.
de Silva
H D
HD
Departments of Allergy, Asthma, and Clinical Immunology, Alfred Hospital and Monash University, Victoria, Australia.
Sutherland
M F
MF
Suphioglu
C
C
McLellan
S C
SC
Slater
J E
JE
Rolland
J M
JM
O'hehir
R E
RE
D000328:Adult; D000368:Aged; D000485:Allergens / Q000276:immunology*; D052179:Antigens, Plant; D018604:Epitope Mapping; D018984:Epitopes, T-Lymphocyte; D005260:Female; D006282:Health Personnel; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007371:Interferon-gamma / Q000378:metabolism; D015848:Interleukin-5 / Q000378:metabolism; D007840:Latex; D020315:Latex Hypersensitivity; D008875:Middle Aged; D010940:Plant Proteins; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism
D000485:Allergens; D052179:Antigens, Plant; D018984:Epitopes, T-Lymphocyte; D015848:Interleukin-5; D007840:Latex; D010940:Plant Proteins; C101800:allergen Hev b 5; D007073:Immunoglobulin E; D007371:Interferon-gamma