Plant defense-related enzymes as latex antigens.
BACKGROUND
Latex allergy is an increasing hazard to people who frequently come into contact with latex products. Of interest concerning this immediate-type allergy is the cross-reactivity to various vegetable foods and pollen. Despite its high prevalence, no adequate explanation has been provided for the cross-reactive antigens.


OBJECTIVE
We have hypothesized that a series of plant defense-related proteins act as latex allergens, as well as vegetable food allergens. To evaluate this hypothesis, hydrolytic enzymes that are very likely to take on defensive roles in rubber trees were examined for their antigenicity.


METHODS
By applying chromatographic procedures, defense-related enzymes were separated from nonammoniated latex (NAL). Their antigenicity was examined by immunoblotting and ELISA with sera containing IgE antibodies to crude latex proteins.


RESULTS
Three kinds of hydrolytic enzymes (basic beta-1,3-glucanases [35, 36.5, and 38 kd], a basic chitinase/lysozyme [29.5 kd], and an acidic esterase [44 kd]) were separated from NAL. They were recognized by IgE antibodies from a significant number of patients allergic to latex. The basic beta-1,3-glucanases and the acidic esterase were also strongly recognized by IgE antibodies from several atopic subjects who were allergic to various vegetable foods rather than latex products.


CONCLUSIONS
It was ascertained that the three defense-related enzymes separated from NAL constituted part of the latex antigens. Taking together the well-known serologic or immunologic relationships and amino acid sequence similarities of defense-related proteins coming from phylogenetically distant plant species, we can suspect their universal antigenicity and cross-reactivity.
Yagami
T
T
Division of Medical Devices, National Institute of Health Sciences, Tokyo, Japan.
Sato
M
M
Nakamura
A
A
Komiyama
T
T
Kitagawa
K
K
Akasawa
A
A
Ikezawa
Z
Z
D002688:Chitinases / Q000276:immunology* / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D003429:Cross Reactions / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D004950:Esterases / Q000276:immunology* / Q000302:isolation & purification; D005512:Food Hypersensitivity / Q000276:immunology; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000276:immunology*; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000032:analysis / Q000276:immunology; D007840:Latex / Q000276:immunology*; D010940:Plant Proteins / Q000276:immunology / Q000302:isolation & purification*; D017421:Sequence Analysis; D014675:Vegetables / Q000276:immunology
D007840:Latex; D010940:Plant Proteins; D007073:Immunoglobulin E; D004950:Esterases; D002688:Chitinases; D004693:Glucan Endo-1,3-beta-D-Glucosidase