Monoclonal antibody-based method for measuring olive pollen major allergen Ole e 1.
BACKGROUND
Olive tree pollen is an important cause of inhalant allergy in Mediterranean countries. The major allergen of this pollen, Ole e 1, has caused reactions in the sera of >80% of olive-sensitive patients. Accurate standardization of allergenic products for diagnosis and immunotherapy is essential to guarantee their quality, and measurement of the major allergen content is becoming an important aspect of standardization procedures.


OBJECTIVE
To develop a two-site enzyme-linked immunoadsorbent assay (ELISA) for the quantification of Ole e 1.


METHODS
BALB/c mice were immunized with purified natural Ole e 1. After fusion and screening by direct ELISA, one of the monoclonal antibodies (5A3) was selected as the capture antibody in an ELISA for Ole e 1 quantification. Bound allergens were detected by a combination of biotinylated Ole e 1-specific polyclonal rabbit antibody and peroxidase-conjugated streptavidin. This ELISA was subsequently evaluated and compared with other techniques.


RESULTS
The developed ELISA was highly reproducible and sensitive, with a detection limit of 0.5 ng/mL and a practical range of 1 to 10 ng/mL. The Ole e 1 content ranged from 3 to 50% of the total protein among the nine Olea europaea pollen extracts studied. The assay also detected Ole e 1-like proteins in pollen from other Oleaceae. Correlation was good between the Ole e 1 content determined by ELISA and scanning densitometry and the immunoglobulin E-binding activity of the extracts.


CONCLUSIONS
The described Ole e 1 ELISA is sensitive, reproducible, specific, and reliable, and therefore, can be helpful for standardization of olive pollen extracts intended for clinical use.
Arilla
M Carmen
MC
Research and Development Department, Bial-ARISTEGUI, Bilbao, Spain.
Eraso
Elena
E
Ibarrola
Ignacio
I
Algorta
Jaime
J
Martínez
Alberto
A
Asturias
Juan A
JA
D000485:Allergens / Q000032:analysis*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D052179:Antigens, Plant; D004797:Enzyme-Linked Immunosorbent Assay; D051379:Mice; D008807:Mice, Inbred BALB C; D010940:Plant Proteins / Q000032:analysis* / Q000276:immunology / Q000302:isolation & purification; D011058:Pollen / Q000276:immunology
D000485:Allergens; D000911:Antibodies, Monoclonal; D052179:Antigens, Plant; C081946:Ole e I protein, Olea europaea; D010940:Plant Proteins