HR-Test (Histamine-Release Test) is an in-vitro cellular allergy diagnostic test based on adsorption of histamine to glassfiber coated microtiter plates.
HR-Test gives the possibility of testing any allergen being suspected of causing a type 1 allergy.
The HR-Test System
HR-Test is an in-vitro method to detect allergen induced histamine release from basophil leukocytes by the use of a glass fiber method. The test is performed in microtiter plates or microwell strips coated with glass fibers. The basophil leukocytes of the blood samples are challenged with allergens. The glassfibers bind histamine with high affinity and selectivity (1).
Heparinized blood (25 μL per well) is challenged with buffered allergen dilutions, at various concentrations, for 60 min. at 37°C.
There are two ways of measuring histamine release, either by the direct or passive sensitization method:
- The direct method, based on allergen induced histamine release from patients own cells, which means that the analysis has to be performed within 48 hours after blood drawing.
- The passive sensitization method2, where patient serum is used for analysis. Passive sensitization allows testing beyond 48 hours after blood drawing.
Released histamine is adsorbed to the glass fiber matrix and subsequently detected fluorometrically (OPA-method) by HISTAREADER™ 501-1.
Results are classified as HR-Class 0-3 when using standard panels, whereas testing of an allergenic material/sample is classified as Positive or Negative.
If the HISTAREADER™ 501-1 is available in the laboratory the complete analysis is performed locally.
If the HISTAREADER™ 501-1 is not available the HR-Test plates / strips can be shipped to another laboratory equipped with a HISTAREADER™ 501-1 and after analysis, results are sent back to the local laboratory / Doctor.
- Incubation of basophils with allergens
- Histamine binds to glass fiber matrix
- Elution of the histamine followed by fluorometric detection