Flow CAST® Basophil Activation Test - BUHLMANN

Flow CAST® Basophil Activation Test


CAST® is the standardized, proven & assessable Basophil Activation Test Portfolio.
An accurate biomarker of an allergic reaction… in a vial.


Flow CAST® is for Research Use Only in the US. Not for use in diagnostic procedures.
Health Canada Licence: 101781

The Flow CAST®(Cellular Allergy Stimulation Test) is intended for the determination of basophil activation in whole blood samples by flow cytometry. Our unique marker combination – CCR3 and CD63 – combines the simple gating properties for basophil detection by CCR3 with the solid application of the proven activation marker CD63 in one. Thanks to its easy protocol and smart marker combination the first results can be obtained within one hour – perfect conditions for laboratories.

CCR3 as Basophil Marker

CCR3 is detected with a PE-fluorescence labelled monoclonal antibody. This gating of basophil cells is significantly easier than with any other commercially available BAT.

CD63 as Activation Marker

The cell surface marker of basophils, CD63  is detected by a FITC-fluorescence labeled monoclonal antibody. CD63 is currently the best-validated basophil activation marker directly linked to basophil degranulation.


The first control, anti-FcEpsilonRI, is a highly specific monoclonal antibody binding to IgE receptor. The second control, a tripetide (fMLP) activates the basophils by a non-immunological way.

CD203c as Activation Marker

The CD203c is an other basophil activation marker in addition to the CD63. Our CD203c Reagent Set (RUO) is intended for the use within an extended protocol for the Flow CAST® kit, allowing the measurement of both activation markers, CD63 and CD203c, with two different fluorescence labelled antibodies.
* References available upon request.

Flow CAST® Product Information

Method Flow Cytometry
Time to result 1 h (approx.)
Sample type 50 µl EDTA whole blood
Marker CCR3-PE / CD63-FITC
Catalog Number see below
Patents US 8,563,258 B2; EP 2 037 269 B1
Status RUO

Flow CAST® + CD203C REAGENT SET Product Information

Method Flow Cytometry
Time to result 1 h (approx.)
Sample type 50 µl EDTA whole blood
Marker CCR3-PE / CD63-FITC / CD203c-PE-DY647
Catalog Number see below

Download IFU and Catalog Numbers

View the appropriate tab below for your location (US or Canada) and click on the blue underlined catalog number to view the Instructions for Use.

Flow CAST® (Basophil Activation Test) – FK-CCR-U
CD203c Reagent Set – B-CCR-203SET-U

Flow CAST®(Basophil Activation Test) – FK-CCR
CD203c Reagent Set – B-CCR-203SET-U

Main applications for Flow CAST®

The CAST® assays can be used for a variety of applications. Further information about specific fields of allergy, ask for independent testing on Cellular Allergy.

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Flow CAST Overview Video

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