Fluorescently-labeled RNA packaging into HIV-1 particles: Direct examination of infectivity across central nervous system cell types.
HIV penetrates the central nervous system (CNS), and although it is clear that microglia and to a lesser extent astrocytes are infected, whether certain other cell types such as neurons are infected remains unclear. Here, we confirmed the finding that RNAs of both cellular and viral origins are present in native HIV-1 particles and exploited this phenomenon to directly examine HIV-1 infectivity of CNS cell types. Using in vitro transcribed mRNAs that were labeled with a fluorescent dye, we showed that these fluorescent mRNAs were packaged into HIV-1 particles by directly examining infected cells using fluorescence microscopy. Cells in culture infected with these labeled virions showed the fluorescent signals of mRNA labels by a distinct pattern of punctate, focal signals within the cells which was used to demonstrate that the CXCR4-tropic NL4-3 strain was able to enter microglia and to a lesser extent astrocytes, but not neurons. The strategy used in the present study may represent a novel approach of simplicity, robustness and reliability for versatile applications in HIV studies, such as the determination of infectivity across a broad range of cell types and within sub-populations of an individual cell type by direct visualization of viral entry into cells.
Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA; School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China.
Ruqiang
R
Xu
Department of Pharmacology and Toxicology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA; Department of Immunology, Florida International University Herbert Wertheim College of Medicine, Miami, FL 33199, USA.
Nazira
N
El-Hage
Department of Pharmacology and Toxicology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA; Department of Immunology, Florida International University Herbert Wertheim College of Medicine, Miami, FL 33199, USA. Electronic address: smdever@vcu.edu.
Seth M
SM
Dever
D001253:Astrocytes / Q000821:virology; D002478:Cells, Cultured; D002490:Central Nervous System / Q000821:virology*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000378:metabolism; D015497:HIV-1 / Q000302:isolation & purification* / Q000502:physiology*; D006801:Humans; D017628:Microglia / Q000821:virology; D008856:Microscopy, Fluorescence; D009474:Neurons / Q000821:virology; D012367:RNA, Viral / Q000737:chemistry*; D013194:Staining and Labeling / Q000379:methods*; D019065:Virus Assembly
D005456:Fluorescent Dyes; D012367:RNA, Viral
Central nervous system; Fluorescent dye; HIV-1; RNA; Viral packaging