INTENDED USE

The Food IgG LIA Test is for measuring the relative amount of food-specific IgG antibody to 90 foods in human serum. The values obtained must always be correlated with the clinical presentation, since elevation of a certain food-specific antibody by itself does not necessarily mean disease.

Epidemiological studies have shown that up to 45% of the population will have varying degrees of reaction to certain foods [1,2]. Most patients often show gastrointestinal symptoms and skin reactions, but they are not limited to this. The reactions of different people to the same food may show very different symptoms in each system [3]. Involved organs involve digestion, skin, nerves, spirit, breathing, skeletal muscles and other systems, and may also manifest as genitourinary system and cardiovascular system, as well as fatigue, dizziness, headache and difficulty sleeping. Common foods that induce the above reactions include milk, eggs, wheat, nuts, soybeans, and various fruits, seafood, and vegetables.

In theory, after food enters the digestive tract, it should be digested to the level of amino acids, glycerol and monosaccharides, so that it can be completely converted into energy for the human body. However, due to individual differences, when the ingested macromolecular food protein cannot be completely digested and enters the body through the intestinal mucosa, it will stimulate the autoimmune system to produce food specific IgG antibodies, which form immune complexes with food macromolecules and deposit in the body, so as to induce the occurrence of various clinical symptoms. [3]

The above reaction may take several days or longer to show clinical symptoms, and its slow pathogenic process and a wide range of food types need to be analyzed and judged by specific IgG antibody detection. The test can provide doctors with more reference information about food reactions and provide a basis for making a true and accurate clinical diagnosis.

ASSAY PRINCIPLE

The test is based on the principle of the line immune assay (LIA).

Specific allergens are applied as lines on a nitrocellulose membrane. The nitrocellulose membrane is blocked to prevent unspecific reactions. During incubation of a strip with diluted patient samples, autoantibodies present in the sample will bind to the antigens on the strip. For the detection of the bound antibodies, an alkaline phosphatase labeled anti-human IgG antibody is used. After addition of the substrate solution, the appearance of purple blue lines indicates the existence of (auto) antibodies against the respective antigens.

FIGG与体检封面(3).png

斯德润诊断

Line Immuno Assay (LIA) for the Detection of Food IgG