Virucidal effect of myeloperoxidase on human immunodeficiency virus type 1-infected T cells

Abstract

Myeloperoxidase is virucidal to human immunodeficiency virus type 1 (HIV-1) in the persistently infected CEM human T-cell line or in acutely infected human peripheral blood mononuclear cells, as judged by viral infectivity and P24 radioimmunoassay. HIV-1 was specifically inactivated by low doses of the human myeloperoxidase (1.4 to 14.3 mU/ml) and the cells were spared. A higher enzyme concentration (143 mU/m) was cytotoxic, but uninfected CEM cells and normal lymphocytes were resistant to -143 mU of myeloperoxidase per ml. The enzyme was virucidal with the Cl -present in medium and did not require exogenous H202.Catalase, an antioxidant enzyme, partially inhibited the virucidal effect of myeloperoxidase. Hence, the H202 probably came from the HIV-infected cells themselves. These in vitro findings indicate that the myeloperoxidase system is capable of inactivating HWV-1 of infected cells.Neutrophils and monocytes of several mammalian species contain in their primary lysosomal granules the heme enzyme myeloperoxidase (MPO). This enzyme and other mammalian peroxidases, such as the lactoperoxidase (LPO) in milk and saliva and eosinophil peroxidase in eosinophils, form a powerful microbicidal system which is effective against a number of microorganisms, including viruses (5, 13,14). Stimulation of neutrophils results in a respiratory burst with the metabolic production of H202 (2). In its presence, MPO oxidizes Cl -to produce hypochlorous acid, which has strong oxidant properties (10, 15).Individuals infected with the human immunodeficiency virus (HIV) were recently reported to have depressed glutathione levels in the plasma and lungs (3). Since glutathione, the most abundant intracellular thiol, plays a key role as an antioxidant, oxidant stress may now be considered a factor in the pathogenesis of AIDS (9).We (25)

Antimicrobial activity of a porcine myeloperoxidase against plant pathogenic bacteria and fungi

“…The antimicrobial activity of myeloperoxidase has been intensively studied in mammalian systems (Klebanoff 1968;Wright et al 1983;Chase and Klebanoff 1992;Chochola et al 1994;Cooray and Björck 1995;Lincoln et al 1995;Hampton et al 1996;Lefkowitz et al 1996). However, few experiments have been conducted to evaluate this enzyme closely for its © 1999 The Society for Applied Microbiology, Journal of Applied Microbiology 86, 211-220 usefulness in controlling plant pathogens (Jacks et al 1991).…”

The importance of myeloperoxidase enzyme activity in the pathogenesis of Crimean–Congo haemorrhagic fever

“…MPO has three isoenzymes: MPO I, II and III, and plays an important role in the defence mechanism against microorganisms (Wright et al, 1990;Miyasaki et al, 1987;Rocha et al, 2002). This enzyme, purified for the first time by Agner (1941), is one of the important proteins of azurophilic granular leukocytes, is found in their cytoplasm with other antimicrobial proteins and is effective on many micro-organisms, especially viruses (Olsson et al, 2004;Chochola et al, 1994).…”

Human recombinant myeloperoxidase antiviral activity on cytomegalovirus

“…As regards the effect on viruses, native myeloperoxidase puri®ed from neutrophils was shown to inactivate in¯uenza virus [Yamamoto et al, 1991] and HIV-1 virus [Klebanoff and Kazazi, 1995]. Availability of human recombinant form of the enzyme [Moguilevsky et al, 1991] facilitated further studies and demonstrated its virucidal effect on HIV-1 virus [Moguilevsky et al, 1992;Chochola et al, 1994]. To extend results obtained with RNA viruses, myeloperoxidase activity was tested on a DNA virus of the herpesviruses family, namely human cytomegalovirus.…”