Native Art v 1 and recombinant Art v 1 are able to induce humoral and T cell-mediated in vitro and in vivo responses in mugwort allergy.
BACKGROUND
Mugwort pollen is an important allergen source in hay fever and pollen-related food allergy. Little is known about the clinical relevance of the major mugwort allergen Art v 1 and its importance in allergy.


OBJECTIVE
In this study we aimed to investigate the allergenicity of mugwort extract compared with the allergenicity of native (n)Art v 1 and recombinant (r)Art v 1, one major allergen of mugwort, in vivo and in vitro.


METHODS
Thirty-two patients allergic to mugwort and 10 control subjects were investigated by means of skin prick and nasal provocation testing with different concentrations of mugwort extract, nArt v 1, and rArt v 1. nArt v 1 was purified from aqueous mugwort extract, and rArt v 1 was cloned, expressed in Escherichia coli, and then purified. The in vitro allergenicity was measured by means of ImmunoCAP, ELISA, ELISA-inhibition experiments, and T-cell proliferation assays.


RESULTS
nArt v 1 and rArt v 1 were able to elicit positive in vivo and in vitro reactions. The IgE-binding capacity, as determined by means of ELISA, was slightly higher for nArt v 1 than for rArt v 1, and both allergens were able to induce T-cell proliferation in sensitized patients. However, rArt v 1 elicited a reduced response in skin and nasal provocation tests compared with nArt v 1. Compared with mugwort extract, both nArt v 1 and rArt v 1 showed lower sensitivity in patients with mugwort allergy in vivo.


CONCLUSIONS
Art v 1, either in its native or recombinant form, is able to induce allergic reactions in patients with mugwort allergy. rArt v 1 induced comparable humoral and cell-mediated responses in vitro but showed reduced in vivo allergenicity compared with biochemically purified nArt v 1.
Schmid-Grendelmeier
Peter
P
Swiss Institute of Allergy and Asthma Research (SIAF), Davos, Switzerland.
Holzmann
David
D
Himly
Martin
M
Weichel
Michael
M
Tresch
Sandra
S
Rückert
Beate
B
Menz
Günter
G
Ferreira
Fatima
F
Blaser
Kurt
K
Wüthrich
Brunello
B
Crameri
Reto
R
D000328:Adult; D000485:Allergens / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D052179:Antigens, Plant; D019306:Artemisia / Q000276:immunology*; D002478:Cells, Cultured; D004306:Dose-Response Relationship, Immunologic; D000939:Epitopes / Q000276:immunology; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D009299:Nasal Provocation Tests; D010936:Plant Extracts / Q000276:immunology; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D006255:Rhinitis, Allergic, Seasonal / Q000276:immunology*; D012882:Skin Tests; D013601:T-Lymphocytes / Q000276:immunology*
D000485:Allergens; D052179:Antigens, Plant; C102724:Art v 1 protein, mugwort; D000939:Epitopes; D010936:Plant Extracts; D010940:Plant Proteins; D011994:Recombinant Proteins; D007073:Immunoglobulin E