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 ease 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 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.
There is also growing recognition of their capacity to modulate adaptive immunity.
Select the population of R2, which contains the population of basophils.
Using the fluorescence intensity of CD63 analyze the results.
The histogram is a representations 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 for 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 higly 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 following histogram corresponds to the analysis of a blood sample from a healthy individual using the Basostep. Using the fluorescence intensity of CD63 analyze the results.