Benzylpenicillin +-acid, minor determinant mix allergen for use with BÜHLMANN CAST® ELISA and Flow CAST® assays 4 stimulations

BÜHLMANN CAST® Allergens are optimized for in vitro Basophil Activation using BÜHLMANN CAST® assays: CAST® ELISA (EK-CAST) and Flow CAST® (FK-CCR).
CAST® drug allergens are delivered lyophilized. Before usage in CAST® assays, they are to be reconstituted with test specific Stimulation Buffer: CAST® ELISA: B-CAST-STB and Flow CAST®: B-CCR-STB.
Add 250μl Stimulation Buffer into the vial and vortex until the lyophilized material has completely dissolved. For some allergens an additional dilution with Stimulation Buffer is recommended.
Remark: Some individuals react positive either at high or at low allergen concentrations, whereas others react positive over a broad range of concentration.
Storage and Stability: Unopened CAST® Allergens are to be stored at the temperature specified on the label until to the expiration date.
Important: Reconstituted or diluted allergens must not be stored and used again!
Optimal time period for stimulation tests: For optimal results, CAST® assays should be run between 3 and 12 weeks after an allergic reaction to the presumed allergen, although specific basophil reaction is often persistent over a longer time period. Blood samples must be drawn for CAST® assays before carrying out a skin test or in vivo provocation with the presumed allergen as in vivo exposure to an allergen can cause an activation of the leucocytes.
Limitations: A negative CAST® assay result for a specific allergen does not exclude potential (even serious) clinical symptoms. Individuals who developed „allergic“ reactions towards protein or drug allergens in the past and whose CAST® assay was negative, should thus be verified with additional methods like the in vivo provocation or skin test before a drug is administered or a patient is exposed to the allergen.
Concentrations and cut-off: Concentrations and cut-off of these allergen groups were optimized regarding maximum specificity und sensitivity. Concentrations to be used in the test and cut-off of individual allergens are reported in the specifications of the allergens. For Flow CAST®, BÜHLMANN recommends the application of the stimulation index (SI) as an additional diagnostic criterion. The SI is defined as the ratio of allergen specific basophil activation and background activation.
Remarks: In order to apply allergen specific cut-offs, QC criteria published in the CAST® instructions must be fulfilled. Cut-offs should serve only as recommendations. Clinically defined cut-offs should be established by each laboratory or through clinical studies.

Product Details:
Product code: BAG2-C12
Content per vial: 250µg
Additional dilution: 1:5
Concentration in stim for CAST ELISA: 200µg/ml
Cut off for CAST ELISA: ≥ 40pg/ml
Concentration in stim for Flow CAST: 225µg/ml
Cut off for Flow CAST: ≥ 5% CD63; SI ≥ 2