Thioredoxin treatment increases digestibility and lowers allergenicity of milk

A Pepsin-Resistant 20 kDa Protein Found in Red Kidney Bean (Phaseolus vulgarisL.) Identified as Basic Subunit of Legumin

“…8) It has been reported that a buried, rigid disulfide (Cys106-Cys119) maintains the conformation of -lactoglobulin, a major milk allergen. 9) In this study, it was found that a 20-kDa polypeptide in red kidney bean, identified as a basic subunit of legumin, was remarkably tolerant of pepsin digestion. Digestibility by pepsin is thought to be a parameter of the allergenicity of unknown proteins.…”

Protein digestibility and relevance to allergenicity.

“…Buchanan and colleagues (Buchanan et al 1997;del Val et al 1999) reported that when structure of the major allergens from these foods is disrupted by reduction of disulfide bonds, the allergens were strikingly sensitive to pepsin digestion and lost their ability to elicit allergic reactions in previously sensitized dogs. Standardization of the assay conditions (such as pepsin concentration, pH, and temperature) has been described in the U.S. Pharmacopia (1990) and is sometimes referred to as SGF.…”

Assessment of protein allergenicity on the basis of immune reactivity: animal models.

“…This decrease was demonstrated first with the major allergens of wheat [this decrease was shown with gliadins and glutenins in dogs as well as in humans (Buchanan et al 1997)] and more recently with the major milk allergen β-lactoglobulin (del Val et al 1999). Further research with β-lactoglobulin revealed that, in addition to decreasing the skin-test challenge response in animals previously sensitized to the native protein, thioredoxin treatment alleviated the clinical symptoms manifested by the dog (vomiting and diarrhea or constipation).…”