CD203C Reagent set for use with BÜHLMANN Flow CAST® ELISA 100 tests

The BÜHLMANN CD203C Reagent Set is for Research Use Only and is intended for the use within an extended protocol for the Flow CAST® kit. It contains an additional staining reagent allowing the measurement of both activation markers, CD63 and CD203c, on basophilic granulocytes in whole blood by flow cytometry after antigen stimulation. In addition, the reagent set contains stimulation buffer without IL-3 which allows the optimal stimulation of the CD203c marker.

Specimen collection and storage: It is recommended patients avoid systemically administered antiallergenic drugs such as corticosteroids, chromoglycic acid (DSCG) for at least 24 hours prior to blood sampling. Collect sufficient blood in K-EDTA venipuncture tubes up to the specified volume. In tubes which are filled < 50 %, the EDTA concentration in the sample is higher and thus may give false negative results. 1 ml of whole blood is sufficient for about 18 tests. Perform the cell stimulation immediately or store the blood sample refrigerated (2-8°C) for up to 24 hours. In order to be able to detect responses to drugs, use blood samples only for up to 3 hours after collection. Do not centrifuge or freeze blood samples.

It is vital to use the reagent set specific stimulation buffer with IL-3 for the Flow CAST® reagent set and the one without IL-3 for the CD203c reagent set.
Interpretation of Results: In order to obtain optimal sensitivity and specificity, different cut-off values should be applied for different groups of allergens. Each laboratory should determine their own cut-off values for CD63 and CD203c.