MPO APC

The clone 8/9, a mouse monoclonal antibody selectively binds with myeloperoxidase (MPO), a glycoprotein present in the granules of myeloid cells. MPO is critical for an optimal oxygen-dependent microbicidal activity of myeloid cells. The MPO generally appears in the myeloblast stage of myeloid cell differentiation. It is the most common functional protein of myeloid cells and is involved in the process of inflammatory immune responses mediated by myeloid cells. The primary translation product of MPO undergoes glycosylation with the production of 89 kDa hemefree 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 alpha-chain and the 14 kDa MPO beta-chain. MPO gene expression may serve as an additional marker for subclassification of acute leukemias and may be used to identify leukemic cells arrested at an early stage of the myeloid differentiation pathway.