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Updated: Jul 10, 2026
Isolation, Transfection, and Culture of Primary Human Monocytes
Published on: December 16, 2019
The contribution of peroxynitrite generation in HIV replication in human primary macrophages
Stefano Aquaro1, Carolina Muscoli, Alessandro Ranazzi
1Faculty of Pharmacy, University of Catanzaro Magna Graecia, Roccelletta di Borgia, Catanzaro, Italy. aquaro@uniroma2.it
Background:
Monocytes/Macrophages (M/M) play a pivotal role as a source of virus during the whole course of HIV-1 infection. Enhanced oxidative stress is involved in the pathogenesis of HIV-1 infection. HIV-1 regulatory proteins induce a reduction of the expression and the activity of MnSOD, the mitochondrial isoform leading to a sustained generation of superoxide anions and peroxynitrite that represent important mediators of HIV-1 replication in M/M. MnTBAP (Mn(III)tetrakis(4-benzoic acid)porphrin chloride), a synthetic peroxynitrite decomposition catalyst, reduced oxidative stress subsequent to peroxynitrite generation.
Results:
Virus production was assessed by p24 ELISA, western blot, and electron microscopy during treatment with MnTBAP. MnTBAP treatment showed a reduction of HIV-1 replication in both acutely and chronically infected M/M: 99% and 90% inhibition of p24 released in supernatants compared to controls, respectively. Maturation of p55 and p24 was strongly inhibited by MnTBAP in both acutely and chronically infected M/M. EC50 and EC90 are 3.7 (+/- 0.05) microM and 19.5 (+/- 0.5) microM, in acutely infected M/M; 6.3 (+/- 0.003) microM and 30 (+/- 0.6) microM, in chronically infected M/M. In acutely infected peripheral blood limphocytes (PBL), EC50 and EC90 are 7.4 (+/- 0.06) microM and of 21.3 (+/- 0.6) microM, respectively. Treatment of acutely-infected M/M with MnTBAP inhibited the elevated levels of malonildialdehyde (MDA) together with the nitrotyrosine staining observed during HIV-1 replication. MnTBAP strongly reduced HIV-1 particles in infected M/M, as shown by electron microscopy. Moreover, in presence of MnTBAP, HIV-1 infectivity was reduced of about 1 log compared to control.
Conclusion:
Results support the role of superoxide anions in HIV-1 replication in M/M and suggest that MnTBAP may counteract HIV-1 replication in combination with other antiretroviral treatments.
Insights
MnTBAP, a peroxynitrite decomposition catalyst, significantly reduced HIV-1 replication in monocytes/macrophages by inhibiting viral production and maturation. This suggests MnTBAP may be a valuable addition to antiretroviral therapies for HIV-1.
Area of Science:
- Virology
- Immunology
- Biochemistry
Background:
- Monocytes/macrophages (M/M) are key reservoirs for HIV-1, contributing to persistent infection.
- HIV-1 infection exacerbates oxidative stress by reducing mitochondrial superoxide dismutase (MnSOD), leading to increased viral replication.
- MnTBAP, a synthetic peroxynitrite decomposition catalyst, was investigated for its potential to mitigate oxidative stress and inhibit HIV-1.
Purpose of the Study:
- To evaluate the efficacy of MnTBAP in reducing HIV-1 replication in monocytes/macrophages.
- To assess the impact of MnTBAP on viral production, maturation, and infectivity.
- To explore the role of oxidative stress mediators in HIV-1 pathogenesis within M/M.
Main Methods:
- HIV-1 infected M/M and peripheral blood lymphocytes (PBL) were treated with MnTBAP.
- Viral production was quantified using p24 ELISA and western blot.
- Viral particle reduction was visualized via electron microscopy.
- Oxidative stress markers, malonildialdehyde (MDA) and nitrotyrosine, were measured.
Main Results:
- MnTBAP treatment inhibited HIV-1 replication by 99% in acutely infected and 90% in chronically infected M/M.
- Viral maturation (p55 and p24) was significantly suppressed by MnTBAP.
- MnTBAP reduced elevated MDA levels and nitrotyrosine staining, indicating decreased oxidative stress.
- Electron microscopy confirmed a reduction in HIV-1 particles, and infectivity decreased by approximately 1 log.
Conclusions:
- Superoxide anions play a crucial role in HIV-1 replication within M/M.
- MnTBAP effectively counteracts HIV-1 replication and associated oxidative stress.
- MnTBAP shows potential as an adjunctive therapy in combination with existing antiretroviral treatments for HIV-1.
