Comparison of the allergenicity and Ole e 1 content of 6 varieties of Olea europaea pollen collected during 5 consecutive years.
BACKGROUND
Numerous varieties of Olea europaea have been described in Mediterranean countries.


OBJECTIVE
To investigate the immunochemical characteristics of 6 varieties of Olea europaea collected during 5 consecutive years.


METHODS
The varieties Carrasquefio, Manzanillo, Acebuche (wild olive), Hojiblanco, Picual, and Nevado were analyzed. Pollen samples from each variety were collected for 5 consecutive years from the same cultivars by trained personnel. The antigenic and allergenic profiles of these extracts were evaluated by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot using the serum of 29 O. europaea-allergic individuals. Ole e 1 was measured using enzyme-linked immunosorbent assay and purified Ole e 1 and rabbit polyclonal antibodies. Allergenic potency was determined using enzyme-linked immunosorbent assay inhibition and is expressed in histamine equivalent prick units per gram of raw material.


RESULTS
Hojiblanco and Acebuche had the lowest mean +/- SD Ole e 1 content in the 5 years (0.045 +/- 0.029 and 0.059 +/-0.031 microg/microg of freeze-dried material, respectively). The variety with the highest mean +/- SD Ole e 1 content was Picual (0.19 +/-0.075 microg/microg). Hojiblanco had the lowest total biological potency throughout the study. A positive correlation was obtained between rainfall in the winter months and total allergenicity of the 6 varieties.


CONCLUSIONS
The different varieties of O. europaea pollen demonstrated great differences in allergenic potency and Ole e 1 content. These differences were maintained throughout the study, suggesting that they are due to genetic differences intrinsic to the varieties, although certain climatic effects may also play a role.
Fernández-Caldas
Enrique
E
Research and Development, Laboratorios LETI S.L., Madrid, Spain. efernandez@leti.com
Carnés
Jerónimo
J
Iraola
Víctor
V
Casanovas
Miguel
M
D000485:Allergens / Q000032:analysis*; D052179:Antigens, Plant; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D031658:Olea / Q000276:immunology*; D010940:Plant Proteins / Q000032:analysis*; D011058:Pollen / Q000737:chemistry / Q000276:immunology*; D011891:Rain; D013696:Temperature
D000485:Allergens; D052179:Antigens, Plant; C081946:Ole e I protein, Olea europaea; D010940:Plant Proteins