Cell Viability and Cytotoxicity Assay Services

In combination with our MEA analysis or as a stand-alone service, we provide toxicity profiling and safety screening, including information about acute or chronic cell viability and cytotoxicity.

MTS Assay

The CellTiter 96® AQueous One Solution Cell Proliferation Assay (Promega) is a colorimetric method for determining the number of viable cells. Viable cells reduce the dye MTS into a colored formazan that can be detected by measuring the absorbance.

LDH Assay

The CyQUANT LDH Cytotoxicity Kit (Thermo Fisher Scientific) is a simple and stable colorimetric method to quantify cellular cytotoxicity. The plasma membranes of damaged cells release LDH (lactate dehydrogenase) into the cell culture media. Via a coupled enzymatic reaction this extracellular LDH leads to the production of a red formazan that can be detected by measuring the absorbance.

ATP Cell Viability Assay

The Cell Titer-Glo Luminescent Viability Assay (Promega) is a reliable method to determine the number of viable cells in culture via the quantification of ATP, an indicator of metabolic active cells. Adding the specific reagent leads to cell lysis and induction of a luminescence signal proportional to the ATP present. This ATP signal is directly proportional to the number of viable cells.

Proliferation assay

The EdU cell proliferation assay (Abcam) is a sensitive and robust method to detect and quantify cell proliferation in live mammalian cells via measuring DNA synthesis using fluorescence microscopy.

Apoptosis Assay

The RealTime-Glo™ Annexin V Apoptosis Assay (Promega) is a non-lytic method that enables us to perform a continual monitoring of the cells and allows multiple readings from a single well. Using the NanoBiT® technology and an Annexin V fusion protein that binds to phophatidylserine (PS) on the outer leaflet of membranes during the apoptotic process a positive detectable luminescence signal is produced.  This apoptosis assay can be combined with a specific compatible necrosis and/or viability read out.

Necrosis Assay

The CytoTox-Glo™ Cytotoxicity Assay measures the extracellular activity of the intracellular dead cell protease when this protease is released from the membrane of damaged cells. The CytoTox-Glo™ Cytotoxicity Assay is a lytic luminescence assay that can be combined with MEA Assays.

Cytolysis Assay

The Toxilight Non-Destructive Cytotoxicity BioAssay Kit (Lonza) is designed to measure the amount of the enzyme adenylate kinase (AK) that is released into the cell culture medium when cells die. The combination of this enzyme release and a firefly luciferase leads to a luminescence signal that is directly proportional to cytolysis.

Live-Dead-Assay

The LIVE/DEAD™ Viability/Cytotoxicity Kit (Thermo Fisher Scientific) facilitates a simple and fast procedure to differentiate between living and dead cells by fluorescence microscopy. The dye Calcein-AM is degraded to green fluorescing Calcein by intracellular esterase activity while the red-fluorescent ethidium homodimer-1 indicates the loss of plasma membrane integrity.

Customized cell stainings

• specific loss of neurons or glia cells
• identification of sub-populations (e.g. GABAergic, dopaminergic neurons)
• neurite detection and quantification
• neurite outgrowth
• number of synapses
• activation of microglia

These assays are also part of our disease models.