Flow Cytometry
Receptor Quantification using flow cytometry
Oncolines can accurately determine the number of receptors expressed on the surface of cells. This can be cancer cell lines from our in-house collection, or cell lines provided by a client. Measuring the exact number of receptors per cell is highly valuable in the context of antibody-drug-conjugates (ADCs). ADCs often rely on higher receptor numbers for target binding, followed by internalization and release of the payload to exert a tumor-targeted and intracellular effect. The Receptor Quantification service helps to evaluate receptor numbers over a panel of cancer cell lines and to determine which cell lines could be of interest to perform subsequent internalization studies. Besides the relevance of receptor number quantification in the context of ADCs, determination of the exact number of receptor molecules can also be important for the selection of cancer cell lines for transfection purposes. By means of this technique, we can select a cell line with low target expression to create an overexpressing cell line. On the other hand, we can also choose cells with high expression of a specific target and create a knock-down or knock-out in this cell line.
Experimental approach
Cell lines are taken into culture in the media recommended by the supplier for at least one week. Once cells reach a confluence of 70-90%, cells are collected and the expression of the target is determined by flow cytometry (Figure 1). Cells are stained with PE labelled anti-target. The number of receptors per cell can be determined using the BD Quantibrite™ PE Phycoerythrin Fluorescence Quantitation Kit to select cell lines most suitable for ADC (internalization) studies or for transfection purposes to generate overexpression or knock-down of the target of interest.
