Intended Use
Enzyme immunoassay (microtiter strips) for the detection and the quantitative determination of IgG antibodies against 24 Food Allergens in human serum and plasma.
Contents of Kit
Microtiter Plate: For 3 patients with 4 color coded strips with 8 wells each. There are 4 different strips (coded with violet, green, yellow and red color) required per screen (patient). 8x reference antigen is bound on the violet strip. 24 (3x 8) food antigens are bound on the green, yellow and red strips. See attached distribution scheme. Ready-touse. Quantity: 1 x 12 x 8
Enzyme Conjugate IgG: Mouse-a-human-IgG-AP, in proteinacious buffer solution. Ready-to-use. Quantity: 1 x 15 mL
Standards A-D: Human plasma diluted with PBS/BSA, with 0.35, 0.7, 3.5, 17.5, 50 and 100 U/mL of IgG antibodies to egg white. Addition of 0.05% sodium azide. Ready-to-use. Quantity: 1 x 6 x 0.5 mL
Control 1+2: Human plasma including low concentrations of IgG antibodies.Addition of 0.05% sodium azide. Quantity: 1 x 2 x 0.5 mL
Diluent Buffer: Tris/BSA buffer. Addition of 0.05% sodium azide. Ready-to-use. Quantity: 1 x 40 mL
Wash Buffer, Concentrate (10x): PBS + Tween 20. Quantity: 1 x 60 mL
PNPP Substrate Solution: Paranitrophenylphosphate (PNPP), Ready-to-use. Quantity: 1 x 15 mL
PNPP Stop Solution: 1 M sodium hydroxide. Ready-to-use. Quantity: 1 x 15 mL
Adhesive Foil, Quantity: 2 x
Storage
The kit is shipped at ambient temperature and should be stored at 2-8°C. Keep away from heat or direct sun light. The storage and stability of specimen and prepared reagents is stated in the corresponding chapters.The microtiter strips are stable up to 6 w in the broken, but tightly closed bag when stored at 2–8°C.
Performance Characteristics
General Description
Lucretius once said that one man's food may be another man's poison. Individuals with allergies and other types of food sensitivities react adversely to certain foods and food ingredients that others can consume with no problems. Many different types of reactions are involved in these individual adverse reactions. Adverse food reactions may include IgE and non-IgE-mediated primary immunological sensitivities, non immunological intolerances (such as an enzyme deficiency or reactions to certain chemicals), as well as secondary sensitivities.
Adverse immune reactions to foods which are not IgE mediated are often called food "intolerances". The absence of IgE does not make them any less real; instead, other immune mechanisms, such as IgG or IgG4 antibodies are involved. IgG or IgG4-mediated adverse reactions to food are characterized by less severe reactions, are much more common (affecting approx. 45 % of the population) and have delayed onset (2 to 72 hours) after ingestion of an offending substance. Avoiding ingestion of such food (exclusion or rotation diet) is the best treatment to decrease symptoms.
There are several evidences for the involvement of IgG or IgG4 in food "intolerances" e.g.:
• Allergic reactions may occur independently of antigen-specific IgE
• Subsequent decrease of IgG when the offending food is removed from the diet
• Specific serum IgG has been reported in cases of celiac disease, dermatitis, or atopic eczema, as well as in diseases with increased intestinal permeability, and inflammatory bowel disease (IBD)
This evidence leads to the recommendation that IgG or IgG4-specific testing should be considered in cases where the patient shows unclear and chronic disorders, and in cases where classical diagnostics show no evidence.