IgE Reactivity to Profilin in Pollen-Sensitized Subjects with Adverse Reactions to Banana and Pineapple

Abstract

Background: The so-called ‘latex-fruit syndrome’ is a well-documented phenomenon in cross-reactive allergies. By contrast, there is a lack of information about allergy to exotic fruits in patients with a predominant pollen sensitization. Since the ubiquitous protein profilin has been identified as an allergen in natural rubber latex as well as in pollen-related foods, the aim of this study was to investigate the role of profilin in allergy to certain exotic fruits. Methods: Recombinant profilins from banana and pineapple were cloned by a PCR technique after isolation of total RNA using degenerated profilin-specific primers. The unknown 5′ ends of copy DNA (cDNA) were identified by rapid amplification of 5′cDNA ends (5′-RACE) and expression in Escherichia coli BL21(DE3) cells. The recombinant profilins were purified by affinity chromatography using poly-(L)-proline as the solid phase. IgE-binding capabilities were characterized by means of immunoblot and Enzyme Allergosorbent Test (EAST). The cross-reactivity to birch pollen profilin and latex profilin was studied by EAST as well as by immunoblot inhibition experiments. Results: Both banana and pineapple profilin were found to consist of 131 amino acid residues with high amino acid sequence identity to known allergenic pollen and food profilins (71–84%). IgE binding to the recombinant profilins was observed in 7/16 sera from subjects with suspected banana allergy (44%) and in 8/19 sera from subjects with suspected pineapple allergy (42%). Inhibition experiments indicated similar IgE reactivity of natural and recombinant allergens. In addition, high cross-reactivity to birch pollen profilin Bet v 2 and latex profilin Hev b 8 was demonstrated by immunoblot inhibition as well as EAST inhibition experiments. Conclusions: Since a high IgE-binding prevalence of about 40% was obtained in both banana and pineapple allergy, we conclude that profilin is an important mediator of IgE cross-reactivity between pollen and exotic fruits.

Severe Allergy to Sharon Fruit Caused by Birch Pollen

“…Sera from patients with pollen allergy sensitized to profilin show IgE cross-reactivity with fruits and vegetables. Profilin has been implicated in the birch-Rosaceae fruit and the birch-mugwort-celery-spice syndrome [11, 12], and several studies concluded that this protein can also play a role in patients allergic to a variety of other foods [6, 11, 13, 14, 15, 16, 17, 18, 19, 20, 21]. Results of recent studies suggest that IgE antibodies to profilin in foods have little or no clinical relevance [22, 23, 24].…”

A Hypoallergenic Vaccine Obtained by Tail-to-Head Restructuring of Timothy Grass Pollen Profilin, Phl p 12, for the Treatment of Cross-Sensitization to Profilin

“…Patients sensitized to profilins, a family of highly conserved cytoskeletal proteins, may show allergic reactions to pollens and foods from a variety of plants (17)(18)(19)(20)(21)(22)(23)(24)(41)(42)(43)(44)(45)(46). We report the engineering and characterization of a vaccine for the treatment of those patients who exhibit broad pollen and plant food cross-reactivities due to profilin sensitization.…”

“…23), lychee (rLit c 4), cashew nut (rAna c 1), carrot (rDau c 4), hazelnut (rCor a 2), and banana (rMus xp 1; Ref. 19) were expressed in Escherichia coli and purified using poly-L-proline-loaded agarose columns (Amersham Bioscience) as described (22). Natural (n) timothy grass pollen profilin (nPhl p 12) was purified from pollen grains by affinity chromatography using poly-L-proline-loaded agarose (Amersham Bioscience) as described (17).…”

“…Profilins (12-14 kDa) are ubiquitous actin-binding proteins that occur in a variety of eukaryotic organisms and thus represent highly cross-reactive allergens. They have been identified as clinically relevant allergens in tree, grass, and weed pollens as well as in plant-derived food and, accordingly, have been designated panallergens (17)(18)(19)(20).…”

<i>Hevea brasiliensis</i> Latex Allergens: Current Panel and Clinical Relevance

“…Hev b 8 seems to be involved in the latex-fruit syndrome as cross-reactivity could be demonstrated to profilins from celery tuber [46], banana and pineapple [47], and bell pepper [27]. …”