Myeloperoxidase (MPO) is a glycoprotein present in the azurophil (primary) granules of myeloid cells, which appears in the myeloblast stage of myeloid cell differentiation. MPO is he most common functional protein of myeloid cells and is involved in the inflammatory response. It helps to kill microbes by breaking down peroxide in the presence of halide ions, contributing to the bactericidal function of granulocytes. The primary translation product of MPO undergoes glycosylation with production of the 89 kDa heme-free apopro-MPO form followed by incorporation of heme and conversion into the enzymatically active pro-MPO form. Subsequently, pro-MPO becomes targeted to azurophil granules where final processing occurs to produce mature dimeric MPO consisting of the 59-64 kDa MPO _-chain and the 14 kDa MPO _-chain.
Precursor B-cells are surface-CD22 negative, but cytoplasmic CD22 positive. Mature B-lymphocytes.express CD22 also on their surface. The combined staining for MPO and CD22 allows the distinction of mature/immature myeloid cells and B-lymphocytes.
The MPO-C2/CD22 COMBI-IC mAb permits the identification and enumeration of normal and malignant myelomonocytic cells and B lymphoid commited cells in human blood and bone marrow using flow cytometry. Results must be put within the context of other diagnostic tests as well as the clinical history of the patient by a certified professional before final interpretation. Analyses performed with this antibody should be paralleled by positive and negative controls. If unexpected results are obtained which cannot be attributed to differences in laboratory procedures, please contact us.
Antibody MPO-C2 (clone 8E2) reacts with human myeloperoxidase (MPO) expressed by normal and malignant myelomonocytic cells.
The CD22 mAb (clone RFB4) recognizes cytoplasmatic CD22 in precursor B-cells and surface as well cytoplasmatic CD22 on mature B-cells.
In this COMBI-IC Reagent antibody 8E6 is conjugated to FITC, antibody RFB4 is conjugated to Phycoeythrin (PE).
The sensitivity of MPO-C2/CD22 mAb is determined by staining well-defined blood samples from representative donors with
serial-fold mAb dilutions to obtain a titration curve that allows relating the mAb concentration to the percentage of stained cells
and geometric MFI (mean fluorescence intensity). For this purpose, a mAb-concentration range is selected to include both the saturation point (i.e. the mAb dilution expected to bind all epitopes on the target cell) and the detection threshold (i.e. the mAb dilution
expected to represent the least amount of mAb needed to detect an identical percentage of cells). In practice, 50 µl of leukocytes
containing 10^7 cells/ml are stained with 20µl mAb of various dilutions to obtain a titration curve and to identify the saturation point and detection threshold. The final concentration of the product is then adjusted to be at least 3-fold above the detection threshold. In
addition and to control lot-to-lot variation, the given lot is compared and adjusted to fluorescence standards with defined intensity.
PBS pH 7.2, 1 mg/ml BSA, 0.1% NaN3
Nordic-MUbio monoclonal antibody reagents contain optimal concentrations of affinity-purified antibody. For stability reasons this monoclonal antibody solution contains sodium azide. These reagents should be stored at 2-8