Measurement of Superoxide in Phagosomes

Background of Measurement of Superoxide in Phagosomes

Phagocytes increase their oxygen consumption significantly during phagocytosis of microorganisms. the NADPH oxidase NOX2 transfers electrons from the cytoplasmic nicotinamide adenine dinucleotide phosphate (NADPH) to the inner lumen of the phagosome, where molecular oxygen is reduced to O^2-, which is further converted to other highly bactericidal reactive oxygen species (ROS). In addition, during inflammation, some phagocytes are able to produce ROS extracellularly by activating NADPH oxidases located in the plasma membrane. ROS production plays an important role in regulating phagosomal pH to protect against cross-presented antigens in dendritic cells and may also affect the integrity of the phagosomal membrane. Several methods have been developed to measure ROS production inside and outside the cell, and the detection of phagosomal ROS production has received considerable attention.

Fig. 1. The cellular compartment of phagocytosis. (Dupré-Crochet S, et al., 2013)

Superoxide Measurement Services in Phagosomes

During phagosome maturation, ROS production is not an isolated event, but coincides with changes in pH, particle fusion, and ion flux. For many years, CD BioSciences has been working to measure the activity of NADPH oxidase complexes within the phagosome to assess the degree of phagosomal maturation. Our biological scientists use chemiluminescence to determine the amount of ROS present at a given time in a given phagocyte, providing a variety of chemicals that react with ROS and produce a chemiluminescent signal.

• ROS-based excitable dyes, such as luminol and isoluminol.
• Substrate reduction, such as cytochrome c and p-nitro blue tetrazolium.
• Fluorophore oxidation, such as p-hydroxyphenylate, scopoletin, dichlorofluorescein, and dihydrorhodamine.

Here, our bioscientists developed custom procedures to measure phagosomal ROS, enabling real-time measurability of the magnitude and duration of superoxide bursts in the phagosomal lumen.

Why Choose Us

• A very sensitive substrate based assay that measures the activity of the NADPH oxidase complex within the phagosome.
• A short-term assay that measures transient events that occur within the first 20 minutes after the onset of phagosome formation.
• Analysis is performed by flow cytometry, which does not provide the fine temporal resolution of fluorescence spectrophotometry, but it is an excellent method for assessing reaction heterogeneity at the cellular level.
• It is able to be used in the immunology laboratory.
• Enables analysis of the kinetics of phagosomal ROS production at the level of individual phagosomes.

CD BioSciences can meet any reasonable needs of our clients, taking time and budget into consideration for you. Our aim is to be customer-centric and to provide the highest quality services to customers. Our customer service representatives are enthusiastic and trustworthy 24 hours a day, 7 days a week. If you are interested in our services, please feel free to contact us for more information or a detailed discussion.

Reference

1. Dupré-Crochet S, Erard M, Nüβe O. (2013) ROS production in phagocytes: why, when, and where?[J]. Journal of leukocyte biology. 94(4): 657-670.