AffiCHECK® BCR-ABL IS Panel

AffiCHECK® BCR-ABL IS Panel

Intended Use

The AffiCHECK® BCR-ABL IS Panel serves as a quality control tool used to monitor the accuracy of in vitro quantitative detection of BCR-ABL1 translocation mRNA e14a2/b3a2 transcripts and the ABL1 endogenous control mRNA transcript. Specifically designed for analysis using the ​Xpert® BCR-ABL Ultra assay​ on Cepheid GeneXpert® Instrument Systems, this panel ensures precision in measuring the presence of the BCR-ABL1 fusion gene, a hallmark of chronic myelogenous leukemia.

Chronic myelogenous leukemia patients often carry the BCR-ABL1 fusion gene, formed from a translocation between chromosome 9's ABL1 gene and chromosome 22's BCR gene (t(9;22)). Accurate monitoring of BCR-ABL1 transcripts in patient blood plays a crucial role in assessing therapy response.

The World Health Organization (WHO) introduced a set of four primary standards for BCR-ABL1 in 2009 to establish the International Scale (IS). This standardized method, reported as a ratio of fusion transcripts to control gene transcripts (%IS), ensures consistency in assay reporting globally, aiding in standardizing patient care. The %IS measurement can also be expressed as molecular response (MR), indicating the reduction from a standardized baseline of 100% on the IS scale.

The AffiCHECK® BCR-ABL IS Panel is aligned with the WHO International Genetic Reference Panel for Quantitation of BCR-ABL Translocation (WHO Reference Panel), NIBSC code 09/138. Tailored for use alongside the Xpert BCR-ABL Ultra assay, which reports results on the international scale, this panel ensures traceability and accuracy in the quantification of BCR-ABL1 transcripts.

Principal

The AffiCHECK® BCR-ABL IS Panel comprises six distinct components, each meticulously formulated with varying concentrations of BCR-ABL1 (e14a2/b3a2) RNA transcript combined with a fixed amount of ABL1 RNA transcript. These components are designed to yield six distinct levels, quantified as 0.0%IS, 0.0032%IS, 0.01%IS, 0.1%IS, 1%IS, and 10%IS when subjected to analysis on the GeneXpert system using the Xpert BCR-ABL Ultra assay. The assignment of %IS values to each lot of the AffiCHECK® BCR-ABL IS Panel is in accordance with the guidelines specified by the WHO Reference Panel, NIBSC code 09/138, as outlined in the NIBSC Instructions for Use.

Validation and determination of values were conducted by AffiGEN Inc. across three separate lots of the AffiCHECK® BCR-ABL IS Panel. Testing was performed in conjunction with the WHO Reference Panel, utilizing a single cartridge lot of the Xpert BCR-ABL Ultra assay. Statistical tests, including Grubb’s outlier and Bland-Altman analyses, were employed, resulting in the calculation of lot-specific Correction Factors (CF). Subsequently, %IS/MR values traceable to WHO standards were allocated to each level of the AffiCHECK® BCR-ABL IS Panel across all three lots, following the guidelines stipulated in the NIBSC Instructions for Use.

Compenents

The AffiCHECK® BCR-ABL IS Panel pack contains a set of 12 individual single-use vials.  each level represented by two vials. Within these vials, there's a precise composition of 4 mL containing synthetic BCR-ABL1 RNA transcript and synthetic ABL1 control gene RNA transcript. These components are intricately suspended in a stabilizing matrix along with a solution containing non-infectious buffers and preservatives.

Storage conditions

AffiCHECK® BCR-ABL IS Panel must be sored at -20°C. Unopened package remains stable until the indicated expiration date.