Pathogenesis-related protein, thaumatin-like protein 1b is a transdermal sensitizing allergen of mango fruits in mouse models

Food allergens can enter the skin and increase the susceptibility to food allergies by producing immunoglobulin (Ig) E. Mango is a popular fruit worldwide and known to be allergenic. Dermal sensitization may occur around the oral cavity during ingestion of mangoes. However, to date, no allergenic proteins in mangoes have been shown to cause dermal sensitization in humans or animal models. Therefore, we aimed to identify mango proteins that sensitize mice percutaneously. The occiput of BALB/c mice was shaved, and a crude mango extract containing sodium dodecyl sulfate was applied to the skin. Mango protein-specific IgE and IgG1 were produced in response to this treatment. Proteins in mangoes that bind to mouse IgG1 and IgE were purified and identified as thaumatin-like protein 1b (TLP1b). This is the first study to identify TLP1b, a pan-allergen belonging to a family of pathogenesis-related proteins, as a mango allergen causing transdermal sensitization in mice.