Class I chitinases as potential panallergens involved in the latex-fruit syndrome.

Abstract

BACKGROUND:

Latex-fruit cross-sensitization has been fully demonstrated. However, the antigens responsible for this "latex-fruit syndrome" have not been identified. We have recently shown that class I chitinases are relevant chestnut and avocado allergens.

OBJECTIVE:

We sought to evaluate the in vivo and in vitro reactions of purified chestnut and avocado chitinases in relation to the latex-fruit syndrome.

METHODS:

From a latex-allergic population, eighteen patients allergic to chestnut, avocado, or both were selected. Skin prick tests (SPTs) were performed with crude chestnut and avocado extracts, chitinase-enriched preparations, and purified class I and II chitinases from both fruits. CAP-inhibition assays with the crude extracts and purified proteins were carried out. Immunodetection with sera from patients with latex-fruit allergy and immunoblot inhibition tests with a latex extract were also performed. Eighteen subjects paired with our patients and 15 patients allergic to latex but not food were used as control groups.

RESULTS:

The chestnut class I chitinase elicited positive SPT responses in 13 of 18 patients with latex-fruit allergy (72%), and the avocado class I chitinase elicited positive responses in 12 of 18 (67%) similarly allergic patients. By contrast, class II enzymes without a hevein-like domain did not show SPT responses in the same patient group. Each isolated class I chitinase reached inhibition values higher than 85% in CAP inhibition assays against the corresponding food extract in solid phase. Immunodetection of the crude extracts and the purified class I chitinases revealed a single 32-kd band for both chestnut and avocado. Preincubation with a natural latex extract fully inhibited the IgE binding to the crude extracts, as well as to the purified chestnut and avocado class I chitinases.

CONCLUSION:

Chestnut and avocado class I chitinases with an N-terminal hevein-like domain are major allergens that cross-react with latex. Therefore they are probably the panallergens responsible for the latex-fruit syndrome.

• Authors: C Blanco, A Diaz-Perales, C Collada, R Sánchez-Monge, C Aragoncillo, R Castillo, N Ortega, M Alvarez, T Carrillo, G Salcedo
• Journal: The Journal of allergy and clinical immunology (J Allergy Clin Immunol) Vol. 103 Issue 3 Pt 1 Pg. 507-13 (Mar 1999) ISSN: 0091-6749 [Print] United States
• PMID: 10069887 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Allergens
• Antigens, Plant
• Antimicrobial Cationic Peptides
• Latex
• Lectins
• Plant Lectins
• Plant Proteins
• hevein
• Immunoglobulin E
• Chitinases
• Prs a 1 allergen

Topics

• Adolescent
• Adult
• Allergens (adverse effects, chemistry, immunology)
• Antibody Specificity
• Antigens, Plant
• Antimicrobial Cationic Peptides
• Chitinases (adverse effects, chemistry, classification, immunology)
• Cross Reactions
• Female
• Food Hypersensitivity (immunology)
• Humans
• Immunoglobulin E (blood, immunology)
• Latex (chemistry)
• Latex Hypersensitivity (immunology)
• Lauraceae (enzymology, immunology)
• Lectins (chemistry)
• Male
• Middle Aged
• Nuts (enzymology, immunology)
• Plant Lectins
• Plant Proteins (adverse effects, chemistry, classification, immunology)
• Prospective Studies
• Protein Structure, Tertiary
• Skin Tests
• Structure-Activity Relationship