Reported August 01, 2007

(Ivanhoe Newswire) -- There may soon be a new way to get relief from allergy problems.

Researchers in Amsterdam report taking allergens or auto-antigens orally using the lactic acid bacterium, Lactococcus lactis or L. lactis, as a delivery method might be a new strategy for treating various kinds of autoimmune and allergic disorders.

In autoimmune diseases, the immune system cannot distinguish between a body's own substances and foreign substances, so it attacks its own tissues and organs. For example, when the body mistakenly responds to harmless substances -- like dust mites, milk products, and pollen -- this reaction is called an allergy.

The lactic acid bacterium in its natural form is well known for converting milk into cheese and yogurt. It has also been used to make drugs to treat gastroenteritis and is now being used to fight other conditions.

In this study, researchers introduced DNA with the code for a therapeutic protein into the L. lactis bacterium's DNA, which then successfully produced the ovalbumin (OVA) protein. Scientists evaluated the use of OVA-secreting bacteria on mice allergic to ovalbumin. When the OVA-secreting bacteria were able to deliver the protein to the right place in the intestine, mice developed a tolerance for the substance they were previously allergic to.

The research shows L. lactis can be used to induce tolerance toward certain substances. Study authors report the strategy can now be further developed to treat allergic and autoimmune disorders. Because of the growing number of these disorders, there is a need for more effective treatments with fewer side effects.

SOURCE: Gastroenterology, 2007