HOW IT WORKS
Learn how impedance assays work and the innovation behind Axion's products.
Getting started with Maestro Z couldn't be easier. Culture your cells in an Axion multiwell CytoView-Z plate [A]. Load this plate into the Maestro Z system and allow the environmental chamber to automatically equilibrate [B]. Analyze changes in cell proliferation, morphology, viability, and GPCR signaling in the CytoView-Z plate label-free and in real-time with AxIS Z software [C].
WHAT IS IMPEDANCE?
Axion's 96-well CytoView-Z plate has a recording electrode embedded in the culture surface of each well [D]. The Maestro Z platform uses impedance measurements (ohms, Ω) to quantify the presence of cells on the electrode [E]. To measure impedance, small electrical signals are delivered to the electrodes. Cell attachment, spreading, and cell-cell connections block these electrical signals and are detected as an increase in impedance. Impedance is also sensitive to subtle changes in cell conformation, such as those caused by receptor-mediated signaling or cell morphology. Since impedance is non-invasive and label-free, impedance assays can be used to quantify dynamic cellular responses over minutes, hours, and days [F].
CELLULAR IMPEDANCE RECORDINGS
Impedance measures how much electrical signal (teal-colored arrows) is blocked by the electrode-cell interface [G]. When the electrode is uncovered, electrical signal easily passes (thick arrows) and the impedance is low. When cells cover the electrode, less electrical signal passes (thin arrows) and impedance is high. When cells die or detach, the impedance decreases back towards baseline [H].
Discover how impedance-based assays are being used to better characterize cellular processes.
Unique functional profile of your cellsCells grow, attach, and interact differently based on their biological function. Collectively, these properties result in a unique cellular profile. The Maestro Z impedance assay allows you to track this cellular profile, and to distinguish cells based on type, density, morphology, and attachment. The cellular profile can also be used to ensure cell quality and purity, quantify growth rates, and optimize assay timing. All of this information is available without complicated experimental setup or analysis. With the push of a button, the Maestro Z system will maintain environmental control and continuously, non-invasively monitor your cells as long as needed, while providing real-time growth curves and simple endpoint plots.
HeLa cells were seeded into the CytoView-Z plate at varying densities and monitored on the Maestro Z system during the attachment, spreading, and proliferation phases (left, middle). Growth curves for HeLa, A549, and Calu-3 cells illustrate distinct cellular profiles.
Dynamics of cytotoxicityWhen testing a new drug or cell therapy, endpoint assays can tell you whether the cells are dead or alive, but they cannot reveal the dynamics or mechanisms behind the cellular response. With label-free, non-invasive, continuous monitoring, the Maestro Z impedance assay allows you to capture the entire time course of cytotoxicity, revealing not only the degree, but also the dynamics and rate of cell death. Often, the kinetics of the cell response give the most insight into the efficacy and mechanism of a compound.
After application of doxorubicin, the impedance measurements revealed the dynamic response of the A549 cells (left, middle). Using on-plate controls for cell growth (No Treatment Control) and cell death (Tergazyme), the percent cytolysis was tracked in real-time throughout the time course of the response.
Monitor rapid receptor-mediated signaling in real-timeCell signaling pathways communicate messages from outside the cell. When extracellular signal molecules bind receptors on the cell surface, they initiate signaling events inside the cell that determine cell behavior. G-protein-coupled receptors (GPCRs) are the largest class of transmembrane receptors. GPCR binding results in conformational changes and downstream responses that can be measured by impedance. These small changes often occur rapidly, but can last minutes to hours with significant physiological consequences. The Maestro Z impedance assay allows you to sensitively and continuously measure even the dynamics of cell signaling over minutes to hours without disturbing the cell biology.
Calu-3 cells were seeded into the CytoView-Z plate and impedance was continuously monitored on the Maestro Z system. When dosed Isoproterenol (teal), a potent beta-adrenergic receptor antagonist, the impedance assay revealed a short-term dose-dependent decrease in impedance (left). At 20 minutes post-dose, the cells dosed with the highest concentration showed the lowest impedance, while cells dosed with the lowest concentration had already returned to baseline (middle). Cell signaling dynamics varied with compound mechanism (right). Histamine (orange, 100 µM) showed a short rapid decrease in impedance, while Cytochalasin D (gray) caused an initial increase and subsequent decrease in impedance related to actin inhibition and cell cycle arrest.