Measuring oxidative stress has become an essential element in defining features of the immune response, and understanding how cells respond to infection, chronic disease and cancer. Quantifying oxidative stress is also critical to understanding how experimental treatments affect cells, and this information is critical to determining the risks and benefits of a potential new therapy. Oxidative stress can also serve a functional purpose. Phagocytic cells like neutrophils undergo a “respiratory burst” and produce reactive oxygen species (ROS) in order to destroy intracellular pathogens.
Many different molecules and cellular components can be monitored by flow cytometry to characterize aspects of oxidative stress. Like most flow cytometry assays, these characteristics can be measured concurrently and can be customized for individual experimental parameters.
Consider incorporating these different oxidative stress assays to your pre-clinical development pipeline to better monitor how experimental therapies impact cell function.
1. Free Radical Detection
Measuring the presence of intracellular free radicals serves as an indicator of oxidative stress. A variety of molecules can be detected, including reactive oxygen species and reactive nitrogen species. Assays can measure total reactive oxygen species or specific molecules like superoxide, hydrogen peroxide or peroxynitrate.
Glutathione is an intracellular tripeptide (glutamyl-cysteinyl-glycine) with a free sulphydryl group that is an important target of attack for free radicals. Flow cytometry can be used to measure the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) and serves as an indicator of oxidative stress.
3. Lipid Peroxidation
Lipid peroxidation is the process of degradation of lipids, which can be initiated by reactive oxygen species. The byproducts of lipid peroxidation can damage cell membranes and shifts in peroxidation status can be measured by flow cytometry.
Flow cytometry-based oxidative stress assays are more accurate and user friendly than ever before and are worth considering in your future studies.