Abcam, ab105136, Myeloperoxidase (MPO) Activity Assay Kit (Colorimetric)

Size: 100Test
Myeloperoxidase (MPO) Activity Assay Kit ab105136 is a rapid, simple, sensitive, and reliable colorimetric assay suitable for use as a high throughput MPO activity assay. Readout is on any colorimetric (412 nm) plate reader. - Cited in > 90 publications - Individual kit components also available for purchase with a minimum order of 20 units. Contact us to discuss your needs.
Key facts
Detection method:Colorimetric,
Sample types:Tissue Homogenate, Cell culture supernatant, Serum, Other biological fluids, Urine (UTI),
Assay type:Enzyme activity,
Assay time:1h,
Assay Platform:Microplate reader

Product details:
How the assay works
In the Myeloperoxidase (MPO) Activity Assay Kit (Colorimetric) protocol, myeloperoxidase produces HClO from H2O2 and Cl-. The HClO reacts with taurine to generate the taurine chloramine, which subsequently reacts with the DTNB probe to eliminate color (absorbance at 412 nm). The absorbance is inversely proportional to the amount of MPO enzyme.
Myeloperoxidase (MPO) Activity Assay Kit (Colorimetric) protocol summary:
- Add samples to wells (and assay buffer only to wells for standards)
- Add reaction mix to sample wells and incubate for 30 min to 2 hrs
- Add stop mix and incubate for 10 min
- Add TNB reagent/standard to all wells and incubate for 5-10 min
- Analyze with a microplate reader
Technical Note: MPO is unlikely to be detectable in healthy urine but may be elevated in the presence of infection.
How other researchers are using
Myeloperoxidase (MPO) Activity Assay Kit (Colorimetric) has been used in a variety of sample type including:
HEK293T cells
Mice corneal lysates
Mouse uterus samples
References:
1-Han G et al. 2023
2-Singh A et al. 2023
3-Gao Y J et al. 2023
Related and recommended products
For fluorometric detection, we recommend the following kits:
- Myeloperoxidase (MPO) Activity Assay Kit (Fluorometric)
ab111749
- Myeloperoxidase (MPO) Activity Assay Kit (Fluorometric - Red)
ab219925
- Myeloperoxidase (MPO) Peroxidation Activity Assay Kit (Fluorometric)
ab273334
This product is manufactured by BioVision, an Abcam company and was previously called K744 Myeloperoxidase (MPO) Colorimetric Activity Assay Kit. K744-100 is the same size as the 100 test size of ab105136.
Myeloperoxidase (MPO) is a peroxidase enzyme (EC 1.11.1.7) most abundantly expressed in neutrophil granulocytes. It is a lysosomal protein stored in the azurophilic granules of the neutrophil. Myeloperoxidase contains a heme pigment which causes its green color in secretions rich in neutrophils, such as pus and some forms of mucus. Myeloperoxidase catalyzes the production of hypochlorous acid (HClO) from hydrogen peroxide (H
) and chloride anion (Cl-, or the equivalent from a non-chlorine halide). Myeloperoxidase also oxidizes tyrosine to a tyrosyl radical using hydrogen peroxide as an oxidizing agent.
The Safety Datasheet for this product has been updated for certain countries. Please check the current version in the Support and downloads section.

Properties and Storage Information:
Shipped at conditions-Blue Ice, Appropriate short-term storage conditions--20°C, Appropriate long-term storage conditions--20°C, Storage information--20°C

Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
Myeloperoxidase also called MPO is an enzyme that plays a critical role in the body's immune response. This protein has a mass of approximately 150 kDa and exists as a dimer composed of heavy and light polypeptide chains. Myeloperoxidase is prominently expressed in neutrophils and monocytes which are types of white blood cells important for combating infections. The enzyme catalyzes the production of hypochlorous acid and other reactive substances by utilizing hydrogen peroxide and chloride ions. These reactive substances help in neutralizing pathogens during the immune response.
Biological function summary
The generation of reactive oxygen species by myeloperoxidase is essential for microbicidal activity. Myeloperoxidase functions as part of the antimicrobial system in the phagosome which is the intracellular compartment where pathogens are degraded. This enzyme works in conjunction with other components of the immune system such as NADPH oxidase. By generating hypochlorous acid MPO contributes to the oxidative burst a rapid release of reactive oxygen species during the response to pathogens.
Pathways
Myeloperoxidase integrates into the immune defense and inflammatory pathways. In particular it is associated with the neutrophil degranulation pathway where it releases its enzymatic contents to fight off microbes. MPO also interacts with proteins involved in oxidative stress processes such as superoxide dismutase which moderates levels of reactive oxygen species in cells. These interactions ensure balance in the immune response preventing excessive tissue damage during inflammation.
Dysregulated MPO activity can contribute to the development of diseases. For instance myeloperoxidase is linked with atherosclerosis a cardiovascular condition where inflammation and oxidative stress lead to plaque formation in the arteries. It also associates with vasculitis an autoimmune disorder causing inflammation of blood vessels. Both disorders can relate to the inflammatory pathways that involve MPO and proteins like C-reactive protein which serves as a marker of inflammation. Understanding MPO's role in these conditions is important for effective therapeutic interventions.