Nanoparticles affect the immune system as they may interact directly with immune cells and activate them. However, it is possible that nanoparticles also interact with released cytokines and immunologically active enzymes. To test this hypothesis, the activity of myeloperoxidase released from activated neutrophils was measured in the presence of nanoparticles with different chemistry and size. ...

The protozoan Entamoeba histolytica is the etiological agent of amoebiasis, which can spread to the liver and form amoebic liver abscesses. Histological studies conducted with resistant and susceptible models of amoebic liver abscesses (ALAs) have established that neutrophils are the first cells to contact invasive amoebae at the lesion site. Myeloperoxidase is the most abundant enzyme secreted...

We tested the ability of human neutrophils to kill five Candida species and the yeast Torulopsis glabrata. C. parapsilosis and C. pseudotropicalis were found to be killed readily by normal and myeloperoxidase-deficient neutrophils and were selected to probe the myeloperoxidase-independent fungicidal mechanisms of the neutrophil. These organisms were killed with relatively normal (C. parapsilosi...

Ascorbic acid is known to stimulate leukocyte functions. In a recent publication it was suggested that the role of ascorbic acid is to reduce compound II of myeloperoxidase back to the native enzyme (Bolscher, B. G. J. M., Zoutberg, G. R., Cuperus, R. A., and Wever, R. (1984) Biochim. Biophys. Acta 784, 189-191). In this paper we report rapid spectral scan and transient state kinetic results on...

Background: Myeloperoxidase staining is used to differentiate leukemias since several decades. Despite implementation of flow cytometric, cytogenetic and molecular techniques for identification of leukemic blasts, histochemical stains such as myeloperoxidase stain are persistently used for better classification of leukemias. The myeloperoxidase staining is a time consuming and hazardous procedu...

Background—Systemic levels of myeloperoxidase predict prognosis in patients with acute coronary syndromes and are considered a marker of plaque vulnerability. It is not known whether myeloperoxidase is associated with different coronary morphologies (ie, rupture or erosion of the culprit lesion) in patients with acute coronary syndrome. Methods and Results—Twenty-five consecutive patients (aged...

Ascorbic acid is known to stimulate leukocyte functions. In a recent publication it was suggested that the role of ascorbic acid is to reduce compound II of myeloperoxidase back to the native enzyme (Bolscher, B. G. J. M., Zoutberg, G. R., Cuperus, R. A., and Wever, R. (1984) Biochim. Biophys. Acta 784, 189-191). In this paper we report rapid spectral scan and transient state kinetic results on...

The patterns of ANCA staining usually relate closely to antibodies against myeloperoxidase and proteinase-3. C-ANCA is mainly antibodies to proteinase-3 and P-ANCA is antibodies to myeloperoxidase. C-ANCA with antibodies to MPO with clinical sequelae is unusual.

The effect of animal myeloperoxidase (EC 1 .I 1 .1.7) on the viability of a plant pathogen was determined. Lethality of hydrogen peroxide to germinating spores of Asoeraillus flavus increased go-fold enzymically. Singlet oxygen was present but hypochlorite accounted for two-thirds of the increase. The results indicate myeloperoxidase could improve microbial resistance in plants, perhaps transge...