Lipid transfer protein (Ara h 9) as a new peanut allergen relevant for a Mediterranean allergic population.
BACKGROUND
Nonspecific lipid transfer proteins (LTPs) represent potent pollen and food allergens. However, the allergenic properties of peanut LTP have not been studied.


OBJECTIVE
To identify LTP in peanut extract using sera from subjects with peanut allergy and Pru p 3-sensitized subjects from Southern Europe, clone and express this protein, and obtain information on the importance as allergen for these selected patients.


METHODS
Peanut LTP (Ara h 9) was cloned and sequenced by using a combination of bioinformatic and molecular biology tools (PCR, immunoblotting, Basic Local Alignment Search Tool [BLAST] searches). The immunologic properties of Ara h 9, Ara h 1, Ara h 2, and Ara h 3 were studied by using sera from subjects with peanut and peach allergy from Italy by immunoblotting and allergen microarray technology.


RESULTS
Two Ara h 9 isoforms-Ara h 9.01 and Ara h 9.02-were cloned and expressed. Ara h 9 represented a minor allergen for subjects with peanut allergy. However, including Ara h 9 as single component for serologic detection of sensitization to peanut by component-resolved diagnosis seems crucial, because the frequency of sensitization to the classic major peanut allergens Ara h 1, Ara h 2, and Ara h 3 was low in these patients from Southern Europe.


CONCLUSIONS
Ara h 9 is a new member of the LTP allergen family that seems to play an important role in peanut allergy for patients from the Mediterranean area.
Krause
Susanne
S
Research Center Borstel, Borstel, Germany.
Reese
Gerald
G
Randow
Stefanie
S
Zennaro
Danila
D
Quaratino
Donato
D
Palazzo
Paola
P
Ciardiello
Maria Antonietta
MA
Petersen
Arnd
A
Becker
Wolf-Meinhard
WM
Mari
Adriano
A
D055516:2S Albumins, Plant / Q000276:immunology / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000368:Aged; D000485:Allergens / Q000276:immunology* / Q000378:metabolism; D052179:Antigens, Plant / Q000276:immunology / Q000378:metabolism; D010367:Arachis / Q000276:immunology*; D002352:Carrier Proteins / Q000276:immunology* / Q000302:isolation & purification / Q000378:metabolism; D002648:Child; D003429:Cross Reactions / Q000276:immunology; D005260:Female; D006023:Glycoproteins / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D008565:Membrane Proteins; D008875:Middle Aged; D021183:Peanut Hypersensitivity / Q000276:immunology* / Q000378:metabolism; D010940:Plant Proteins / Q000276:immunology* / Q000378:metabolism; D020033:Protein Isoforms / Q000276:immunology / Q000378:metabolism; D055314:Seed Storage Proteins / Q000276:immunology / Q000378:metabolism; D055815:Young Adult
D055516:2S Albumins, Plant; D000485:Allergens; D052179:Antigens, Plant; C500889:Ara h 1 protein, Arachis hypogaea; C500890:Ara h 2 allergen, Arachis hypogaea; C544631:Ara h 9 allergen, peanut; D002352:Carrier Proteins; D006023:Glycoproteins; D008565:Membrane Proteins; D010940:Plant Proteins; D020033:Protein Isoforms; D055314:Seed Storage Proteins; C118207:allergen Ara h3; C030363:lipid transfer protein; D007073:Immunoglobulin E