What is the function of myeloperoxidase?

Myeloperoxidase (MPO) is a key element of the innate immune system and is released primarily by neutrophils to provide defence against invading pathogens. MPO comprises about 5% of the dry mass of the neutrophil and is contained predominantly within the lysosomal azurophilic granules.

Which cells are MPO positive?

Myeloperoxidase (MPO) is the hallmark enzyme of the myeloid lineage. MPO can be detected by cytochemical staining, immunohistochemistry, or flow cytometry. The diagnosis of AML is easy if more than 3% of blast cells are confirmed to be cytochemically MPO positive.

Which cells express MPO?

MPO is a myeloid-lineage restricted enzyme with strong antibacterial properties. During myeloid cell differentiation, MPO is largely expressed by neutrophils [1] where is located within azurophilic granules [2].

Where is myeloperoxidase found?

Myeloperoxidase (MPO), a heme-containing protein, is found in the azurophilic granules of neutrophils and in the lysosomes of monocytes in humans; however, monocytes contain only about a third of the MPO present in neutrophils.

What causes high levels of myeloperoxidase?

Elevated levels of circulating MPO are observed in patients with coronary artery diseases, unstable angina, and acute myocardial infarction [8,136,137,138].

What does myeloperoxidase positive mean?

What does it mean if your MYELOPEROXIDASE ANTIBODY result is too high? A positive result has a high predictive value for microscopic polyangiitis (MPA) in patients with negative test results for systemic lupus erythematosus (antinuclear antibodies) and Goodpasture syndrome (glomerular basement membrane antibody).

What does MPO positive mean?

A positive result has a high predictive value for microscopic polyangiitis (MPA) in patients with negative test results for systemic lupus erythematosus (antinuclear antibodies) and Goodpasture syndrome (glomerular basement membrane antibody).

What is MPO inflammation?

MPO is a white blood cell-derived inflammatory enzyme that measures disease activity from the luminal aspect of the arterial wall. Briefly, when the artery wall is damaged, or inflamed, MPO is released by invading macrophages where it accumulates1.

What is MPO in pathology?

Myeloperoxidase (MPO) (EC 1.11. 1.7) is a member of subfamily of peroxidases. It is most abundantly expressed in immune cells, such as neutrophilic polymorphonuclear leukocytes (neutrophils) and lymphocytes [1,2], monocytes, and macrophages [3], and is also produced in other body cells.

What does a high myeloperoxidase mean?

Elevated MPO levels predict the risk of heart disease in subgroups otherwise associated with low risk4,5. • Elevated MPO levels independently predict the risk of future cardiovascular events in patients presenting with an acute coronary syndrome6,7.