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Updated: May 11, 2026
06:46
Isolation of Exosomes from the Plasma of HIV-1 Positive Individuals
Published on: January 5, 2016
Exosomes derived from HIV-1-infected cells contain trans-activation response element RNA.
Aarthi Narayanan1, Sergey Iordanskiy, Ravi Das
1National Center for Biodefense and Infectious Diseases, George Mason University, Manassas, Virginia 20110, USA.
The Journal of Biological Chemistry
|May 11, 2013
Summary
Human Immunodeficiency Virus-1 (HIV-1) infected cells release exosomes containing trans-activation response element (TAR) miRNA. This exosomal TAR RNA enhances recipient cell susceptibility to HIV-1 infection and modulates apoptosis.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Exosomes are nano-sized vesicles secreted by cells, including those infected with viruses like HIV-1.
- HIV-1 encodes microRNAs (miRNAs) that regulate viral and host gene expression.
- Trans-activation response element (TAR) miRNA is the most abundant HIV-1-derived miRNA.
Purpose of the Study:
- To investigate the presence and role of TAR RNA within exosomes derived from HIV-1 infected cells.
- To determine the mechanism of TAR RNA transport into exosomes.
- To assess the impact of exosomal TAR RNA on recipient cell susceptibility and apoptosis.
Main Methods:
- Detection of TAR RNA in exosomes from HIV-1 infected cell cultures and patient sera using deep sequencing.
- Analysis of exosomal protein content, including miRNA machinery proteins Dicer and Drosha.
- Investigation of TAR RNA nuclear export pathway using CRM1 inhibition.
- Assessing the effect of exosomes on recipient cell infection rates and apoptosis markers (Bim, Cdk9).
Main Results:
- TAR RNA was confirmed within exosomes from HIV-1 infected cells and patient sera, distinct from extracellular Ago2 complexes.
- Exosomes from infected cells contained host miRNA machinery proteins Dicer and Drosha.
- Nuclear transport of TAR RNA into exosomes was identified as a CRM1-dependent process.
- Exposure to exosomes from infected cells increased recipient cell susceptibility to HIV-1 and reduced apoptosis by down-regulating Bim and Cdk9.
- Quantification revealed high levels of TAR RNA in exosomes from infected cell culture and detectable levels in patient serum exosomes.
Conclusions:
- HIV-1 infected cells package TAR RNA into exosomes via a CRM1-dependent mechanism.
- Exosomal TAR RNA contributes to HIV-1 pathogenesis by increasing cell susceptibility and altering apoptosis.
- These findings highlight exosomal cargo as a potential factor in AIDS progression and suggest exosomal TAR RNA as a biomarker.
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