BCR-ABL Fusion Protein kit by Flow Cytometry

The BCR-ABL fusion gene results from the translocation t(9;22). It is the hallmark of chronic myeloid leukemia (CML) and is present in a poor-risk subgroup of precursor B cell acute lymphoblastic leukemia (ALL), which represents 25-30% of adult ALL and 3-5% of childhood ALL. Consequently the detection of the BCR-ABL aberration is of utmost importance for diagnosis and classification of leukemia patients and can also be used as marker for monitoring of BCR-ABL+ leukemias to evaluate treatment effectiveness. So far, the BCR-ABL aberration has been detected by cytogenetics, FISH or PCR, all techniques that are time consuming and require special facilities. 

We developed a simple flow cytometric bead assay for detection of the BCR-ABL fusion protein in cell lysates, using a bead-bound catching antibody against one side of the fusion protein and a fluorochrome-conjugated detection antibody against the other side of the fusion protein.

We conclude that the flow cytometric immunobead assay is a fast and easy technique for specific detection of BCR-ABL proteins in leukemic cells.

1. The main advantages of the IMMUNOSTEP immunobead assay are:

-       not dependent of the breakpoint position in the BCR gene;

-       does not need special laboratory facilities other than a routine flow cytometer;

-       provides results within several hours;

-       and be run in parallel to routine immunophenotyping (no extra technician time needed)

2. Since differentially labeled beads allow multiplexing, it will be possible to develop single tube assays for combined evaluation of multiple different fusion proteins, e.g. per disease category.

3. Consequently, the flow cytometric immunobead assay can contribute to fast and easy diagnosis and classification of leukemias with fusion genes.

4. If sufficient sensitivity can be reached, also monitoring becomes possible.


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