IgE-mediated allergic reactions determination by the analysis of CD63 antigen surface on basophils upon allergen stimulation using Flow Cytometry.
Does not expose the patient to any allergens;
More specific determination of basophils than other tests;
Simple and fast: contains positive and negative controls in lyophilized tubes, for easy handling;
Offering 3 different solutions depending on the clinical needs.
The kit is based on the method described by Sainte-Laudy et al. (1994), where basophil activation by allergens is detected by Flow Cytometry and measured by the increase of CD63 (gp53) at the cellular surface. BasoStep allows the quantitative determination of human basophils degranulation.
Basophils are known to be an early and abundant source of Th2 cytokines and other mediators of Th2 inflammation.
Because of the basophils sensitization with allergen specific IgE, they represent a significant effector population in allergic pathogenesis.
Their ability to modulate adaptive immunity is increasingly recognized.
Select the population of R2, which contains the population of basophils.
Using the fluorescence intensity of CD63 analyze the results.
The histogram is a representation of a lysate normal whole blood sample gated on CD123+/CD203c+/HLA-DR-. Control Negative are represented by the purple histogram and Positive Control by blue histogram.
The test includes the chemotactic peptide N-formyl-Met-Leu-Phe (fMLP) as positive control and a cocktail of antibodies for detection and determination of degranulated basophils activation.
Therefore, BasoStep assay is based on in-vitro stimulation of basophils using fMLP as positive control and subsequent Flow Cytometry analysis of membrane expression of CD63 on basophils after degranulation.
Using defined allergens, this test is able to provide highly reliable information concerning the releasability of IgE-bearing basophils.
When IgE-receptors on basophils are cross-linked by an allergen, the cells undergo degranulation through cytoplasmatic granules containing the CD63 transmembrane protein fuse with the plasma membrane and release inflammatory mediators. Therefore, the CD63 antigen is exposed as a marker of basophil activation.
The histogram corresponds to the analysis of a blood sample from a healthy individual using BasoStep. Using the fluorescence intensity of CD63, we can analyze the results.