Cal-IS (calibrator for International Scale)
Cal-IS (calibrator for International Scale) is a panel of 5 sealed glass vials, with the necessary cellular material for calibration (see Image 1).
Why 5 vials? Five levels of BCR-ABL1 expression are generated by mixing 2 cell lines (K562 / HL-60) in 5 different proportions; K562 (positive for BCR-ABL1) is diluted in a background of HL-60 cells (negative for BCR-ABL1).
The mixture of the cell lines is fractionated in glass vials and then lyophilized by an automatic system. Freeze drying is a key step, since it
allows us to share this material easily and at a lower cost (see Image 2).Each batch produced is analyzed with our RT-qPCR methodology, harmonized at the international scale through the primary calibrators from WHO; this process allows us to assign the nominal value (IS%) to each of the 5 levels of expression.A distinctive characteristic of our product is that with the Calibrator 5 we can estimate the limit of quantification of the test and validate the ability to measure until the MR4.5.
Image 1: Illustrative photo of a complete panel of calibrators (cal-IS).
Image 2: Two panels of cal-IS in its box ready to be sent