Human Myeloperoxidase Quantikine ELISA Kit Summary

Product Summary

The Quantikine Human MPO Immunoassay is a 4.5 hour solid-phase ELISA designed to measure human MPO in cell culture supernates, cell lysates, serum, platelet-poor plasma, saliva, and urine.

Preparation and Storage

Background: Myeloperoxidase/MPO

Myeloperoxidase (MPO) is a heme-containing enzyme belonging to the XPO subfamily of peroxidases. It is an abundant neutrophil and monocyte glycoprotein that catalyzes the hydrogen peroxide dependent formation of hypochlorus acid (HOCl) and other reactive species. Enzymatically active MPO is a disulfide-linked tetramer that contains two heme groups and two copies each of the heavy and light chains. MPO binds Albumin, MMR, Cytokeratin 1 on vascular endothelial cells, HMW Kininogen, and Integrin CD11b/CD18 on neutrophils. These interactions promote MPO clearance, a reduction of nitric oxide and bradykinin levels, reduced vasodilation, and continued neutrophil activation. Neutrophil MPO is stored in cytoplasmic azurophilic granules. Upon cellular activation and degranulation, MPO is delivered into phagosomes where it is required for the killing of phagocytosed bacteria. Activated neutrophils also release granule contents extracellularly. Elevated plasma MPO levels have been associated with a variety of clinical conditions including systemic inflammation, eclampsia, risk of cardiovascular events, vascular endothelial dysfunction, severity of multiple sclerosis, and prospective mortality and oxidative stress during hemodialysis.

Assay Procedure

Refer to the product datasheet for the complete assay procedure.

Bring all reagents and samples to room temperature before use. It is recommended that all samples, standards, and controls be assayed in duplicate.

1.     Prepare all reagents, standard dilutions, and samples as directed in the product insert.

2.     Remove excess microplate strips from the plate frame, return them to the foil pouch containing the desiccant pack, and reseal.

3.     Add 50 μL of Assay Diluent to each well.

4.     Add 50 μL of Standard, control, or sample to each well. Cover with a plate sealer, and incubate at room temperature for 2 hours.

5.     Aspirate each well and wash, repeating the process 4 times for a total of 5 washes.

6.     Add 100 μL of Conjugate to each well. Cover with a new plate sealer, and incubate at room temperature for 2 hours.

7.     Aspirate and wash 5 times.

8.     Add 100 μL Substrate Solution to each well.

9.     Add 100 μL of Stop Solution to each well. Read at 450 nm within 30 minutes. Set wavelength correction to 540 nm or 570 nm.