Have you been wondering how to monitor a cell state or cellular response? From a basic research standpoint, signaling pathways are so intertwined that cell readouts are a must-have to fully understand the consequences when, for example, a specific protein is modified or an epigenetic event occurs. In today’s publishing world, it’s not enough to know that a protein gets phosphorylated when exposed to a known stimulus; you must also know the effect that phosphorylation event has on the behavior of a cell population. From a translational medicine standpoint, knowing how a cell population responds to a potential treatment is critical. This can include, but is not limited to, looking for apoptosis for neurodegenerative diseases, senescence for oncological diseases, and immune responses against viral infections.
Cell states can be monitored by measuring key markers or readouts that correlate to your process of interest. A particular process can have several readouts that can be used with different methodologies. This gives you the ability to measure multiple key markers to guard against false positives and gives you the flexibility to select the marker, application, and detection method that will work best for your experiment.
For example, there are multiple ways to monitor apoptosis by targeting different hallmarks of cell death and signaling pathways. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) is a stain that detects fragmented DNA observed in late-stage apoptosis. It is widely used to detect apoptotic cells using flow cytometry, immunohistochemistry, or fluorescent microscopy. Similarly, Annexin V binding to phosphatidylserine (PS) is often used with flow cytometry to monitor early-stage apoptosis when PS flips within the plasma membrane and appears on the cell surface. Finally, caspase-3 activation can be used with western blots, immunohistochemistry, or fluorescent microscopy to monitor caspase-induced apoptosis.
Senescence can also be monitored in several different ways. One common approach is an assay that measures increased activity of β-galactosidase, a hallmark of senescence. Enzyme activity can be quantitatively measured with fluorescence using flow cytometry or a plate-based assay, or imaged using a staining kit. Cell senescence can also be monitored by detecting the expression senescence markers like p16 INK4A, p21 Waf1/Cip1, and Lamin B1 using western blotting, immunoprecipitation, immunohistochemistry, immunofluorescence, or flow cytometry.
Cell Signaling Technology® has a variety of cellular assay kits and antibody sampler kits that target key markers to help you get started.
