A scratch assay measures the migration of cells across a scratch-induced gap in vitro. It may be used to assess cell proliferation and migration, often in cancer or wound healing studies. Tracking cell migration and proliferation provides a powerful tool to quantify metastatic potential and has proven particularly useful in understanding potential treatments to reduce metastasis in breast cancer.
The scratch assay is an easy and low-cost method to track cell migration in vitro. Real-time measurement across multiple wells can be done label free with Axion BioSystems' Maestro Z, ZHT, Pro and Edge systems. The rate of migration may differ by cell type or treatment and, depending on your cells and protocol, this assay may take several hours or a few days to complete. Continuous, label-free monitoring provides a true kinetic analysis and eliminates the guesswork associated with endpoint-only data.
Triple-negative breast cancer (TNBC) is an aggressive type of cancer with poorer prognoses. It has limited therapeutic options and a high risk of metastatic re-occurrence. In vitro scratch assays can be used to assess cancer cell invasion, a key factor in metastatic potential, and the effect of potential therapeutics. Below is example data (measured in impedance) comparing two breast cancer cell lines monitored continuously.
(A) Scratch through confluent cells on plate.
MCF-7, a hormone-receptor positive breast cancer line, and HCC1806, a triple-negative breast cancer line, were seeded into the CytoView-Z plate. Impedance was continuously monitored on the Maestro Z for 72 hours. Cells were switched to low-serum media for 24 hours prior to scratch induction and treatment with modified citrus pectin (MCP), and then monitored over the next 72 hours. Each cell type exhibited a unique impedance profile during proliferation (C), and showed a sharp decrease in impedance resulting from the scratch (D and E). HCC1806 cells migrated to almost fully cover the gap and impedance nearly recovered to unscratched levels (D). MCF-7 cells migrated very little over the next 72 hours and normalized impedance remained consistently low (E). The addition of modified citrus pectin (MCP) or PectaSol-C slowed migration shown here by a reduced recovery of impedance relative to the untreated condition (F)
Getting started with Maestro Z, ZHT, Pro and Edge couldn't be easier. Culture your cells in an Axion multiwell CytoView-Z plate (Hour 0). Load this plate into the Maestro system and allow the environmental chamber to automatically equilibrate. Observe cells adhering to the plate and proliferating as changes in the recorded impedance signal (Hour 0-72). When cells are confluent, switch to low-serum media for 24 hours. Create the scratch (Hour 96) and add test compounds as required. Track changes in cell migration in the CytoView-Z plate label-free and in real-time with the Impedance Module software (Hour 96+).