Related Experiment Videos
Monocyte/macrophage traffic in HIV and SIV encephalitis
Woong-Ki Kim1, Sarah Corey, Xavier Alvarez
1Division of Pathogenesis, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
Abstract:
This short review focuses on the role of central nervous system (CNS) perivascular macrophages as targets of productive infection of the CNS. Data discussed include the importance of these cells as early targets of infection and their productive infection with AIDS. Many of the immune molecules on perivascular macrophages are also found on subsets of blood monocyte/macrophages, some of which are expanded during human immunodeficiency virus (HIV) infection. These observations paired with the known bone marrow (BM) origin of perivascular macrophages and the BM as a site of HIV infection underscore the importance of the study of monocyte populations in the BM and blood, which are activated and infected as a source of virus that enters the CNS. Data presented and discussed herein suggest a role of HIV-infected BM-derived monocytes as "Trojan horse" cells that traffic to the CNS to become perivascular macrophages. The study of such cells including their timing of infection, activation, and traffic and the role of HIV-specific immune responses controlling their accumulation in the CNS warrant study with regard to CNS neuropathogenesis.
Insights
Central nervous system perivascular macrophages are early targets in AIDS. HIV-infected monocytes may act as "Trojan horses," trafficking to the brain and contributing to neuropathogenesis.
Area of Science:
- Neuroimmunology
- Infectious Diseases
- Cell Biology
Background:
- Perivascular macrophages in the central nervous system (CNS) are crucial in neuroinflammation and infection.
- These cells are identified as early targets for productive infection within the CNS, including during acquired immunodeficiency syndrome (AIDS).
- Immune molecules on perivascular macrophages share similarities with subsets of blood monocytes/macrophages, some of which are altered during human immunodeficiency virus (HIV) infection.
Purpose of the Study:
- To review the role of CNS perivascular macrophages as targets of productive CNS infection.
- To explore the potential of HIV-infected monocytes as vehicles for CNS viral entry and neuropathogenesis.
Main Methods:
- Review of existing data on perivascular macrophage infection and immune molecule expression.
- Analysis of monocyte/macrophage subsets in blood and bone marrow during HIV infection.
- Discussion of the bone marrow origin of perivascular macrophages and its implications for HIV trafficking.
Main Results:
- Perivascular macrophages are early and productive targets of CNS infection, including with HIV.
- Activated and infected monocyte populations in bone marrow and blood are potential sources of CNS viral entry.
- HIV-infected monocytes are proposed as "Trojan horse" cells that migrate to the CNS to differentiate into perivascular macrophages.
Conclusions:
- HIV-infected bone marrow-derived monocytes may serve as a critical "Trojan horse" mechanism for CNS viral dissemination.
- Understanding the timing, activation, and trafficking of these monocytes is essential for elucidating CNS neuropathogenesis in HIV.
- Further research into HIV-specific immune responses controlling monocyte accumulation in the CNS is warranted.