Gliadin is a molecule found on the surface of the Adenovirus (ặd΄-ən-ō-vī΄-rəs), which causes common lung infections. Gliadin’s job is to dig the virus into and between cell walls. Many humans have the dominant genes needed to made antibodies that bind to gliadin and rapidly stop any Adenovirus infection. This is a great survival trait for people who live or work indoors in winter with many other humans.
Gliadin is also found in large quantities in wheat
gluten. When gliadin in gluten becomes water soluble, it is free to bind to cells. If the victim can make antibodies to gliadin, the body then treats those cells as a virus infection.
Gliadin triggers an immune response when it contacts any of a number of cells in the body of genetically susceptible individuals. This response damages the surrounding tissue and thereby has the potential to set off many other heath problems throughout the body.
Gliadin is classified as a member of a family of sequences called prolamines. Prolamines in rye and barley glutens are have their own technical names, but they are often just called gliadin because they are chemically similar and have the same toxic reactions (the actually prolamin from rye is secalin, from barley hordein and from oats avenin).
Gliadin is very unique among foods in that it contains substantial lengths of poly-glutamine. Prolamines in other grains associated with milder gluten sensitivity happen to contain shorter lengths of poly-glutamine.
Gliadin molecules in gluten are not very water soluble, and so they are not very digestible unless they are subject to such processes as fine grinding, baking, fermentation, and chemical treatment and synthesis.
If the gliadin remains intact within the digestive tract (and it is a particularly stable molecule) it can bind to the intestines, especially if the intestine lining is weak or flawed. Significant amounts of gliadin eaten can cross the intestine into the blood stream.
Since the 1970’s, more chemically treated gliadin is in the diet. In the 80’s, Americans increased the amount of wheat they ate; having been told it was healthier than meat. In the 1990’s, additions of “vital gluten” and gluten-based flavors were increased in manufactured foods. In the 2000’s Kansas State University Grain Science Department (and other places) works to increase gliadin content in wheat and may attempt introduction of gliadin in other grains such as rice.