Out of a thousand components in natural rubber latex (NRL), 50-100 are capable producing immune response, 5-10 are potentially allergenic from manufactured products from a singular manufacturer’s studies. Not all allergens trigger the same immune responses across individuals with NRL allergies.
Cross-reactivity typically requires 80-90% homogeneity with another sequence for antibodies to recognize sequence. Stressed plants or bred plants to increase stress tolerance (e.g., genetically modified organisms [GMOs]) may increase particles. Difficult to create a generic NRL allergen test due to the variety of allergens associated with NRL and presence in many plants; allergen tests for each Hev b are available, are good. NRL sensitivity is now called Latex-Fruit Syndrome.
Primary Allergens
- Hev b 1; Rubber elongation factor; involved in rubber biosynthesis; particulate, difficult to aerosolize. Contact allergen.
- Hev b 2; Beta-1,3-glucanase; Plant defense/protein enzyme; anti-fungal, attacks outer surface polysaccharide matrix. Cross-Reactivity: Bell pepper, olive, barley, wheat, soybean, rice, mustard, cucumber.
- Hev b 3; Small rubber particle protein; involved in rubber biosynthesis, partial cross-reactivity with Hev b 1. Cross-Reactivity: Red kidney bean.
- Hev b 4; Microhelix complex; easily aerosolized.
- Hev b 5; Acidic natural rubber latex protein; easily aerosolized. Cross-Reactivity: Kiwi, manioc/cassava.
- Hev b 6.01; Prohevein/Endochitanase; plant defense protein/enzyme; involved in latex coagulation. Cross-Reactivity: Banana, avocado, chestnut, kiwi, pepper, tomato, peach, rice, strawberry, wheat, citrus, turnip, soybean, tobacco.
- Hev b 6.02; Mature hevein (N-terminal); anti-fungal, anti-herbivory (predatory insects). Cross-Reactivity: Banana, avocado, chestnut, kiwi, pepper, tomato, peach, rice, strawberry, wheat, citrus, turnip, soybean, tobacco.
- Hev b 6.03; Marure hevein (C-terminal) Easily aerosolized, attaches to corn starch powder in latex gloves. Cross-Reactivity: Banana, avocado, chestnut, kiwi, pepper, tomato, peach, rice, strawberry, wheat, citrus, turnip, soybean, tobacco.
- Hev b 7; Palatin-like protein; plant defense protein; inhibitor of rubber biosynthesis. Cross-Reactivity: potato, tomato.
- Hev b 8; Profilin; structural, actin-binding protein, strengthens cytoskeleton of plants, promotes intercellular communications, sequence/structure homologous to Birch allergen Bet v 2. Cross-Reactivity: Banana, avocado, chestnut, kiwi, pepper, fig, potato, tomato, celery, carrot, zucchini, pear, apple, peach, cherry, apricot, pineapple, melon, papaya, passion, persimmon, mango, pumpkin, pollens (birch, alder, hazelnut, grasses).
- Hev b 9; Enolase; metabolic (glycolysis) enzyme, associated with latex-mold syndrome. Cross-Reactivity: Alternaria, cladosporium.
- Hev b 10; Mn superoxide dismutase; destruction of radicals, associated with latex-mold syndrome. Cross-Reactivity: Aspergillus.
- Hev b 11; Class 1 chitinase; mostly distinct structures and activities vs. Hev b 6 chitinase, partial cross-reactivities.
- Hev b 12; Lipid-transfer protein; plant defense protein, highly evolved/common to a wide variety of genetically-related and unrelated plants. Cross-Reactivity: Apple, peach, plum, apricot, soybean, corn, wheat, carrot, pollens (mugwort, chestnut).
- Hev b 13; Esterase; very similar to Paladin-like protein Hev b 7. Reclassified as Hev b 7.02. Cross-Reactivity: Potato.
- Hev b 14; Havamine; plant defense protein. Cross-Reactivity: Cucumber.
Undetermined Cross-Reactivity
- Fruits: Jackfruit, Indian jujube
- Vegetables: Pumpkin, Manioc/Cassava, Cucumber, Tomato, Eggplant/Aubergine, Zucchini, Turnip
- Pollens: Cypress, Goldenrod
References
Grier, T. (2015). The why behind latex and cross-reactive foods. Allergy & Asthma Network.