Modeling HSV-1 Latency in Human Embryonic Stem Cell-Derived Neurons

Area of Science:

• Neurovirology
• Stem Cell Biology
• Infectious Diseases

Background:

• Herpes Simplex Virus 1 (HSV-1) establishes lifelong latency in human peripheral ganglia, with reactivation causing significant disease.
• Current latency models using animal systems are complex and lack human-specific molecular tools.
• Investigating HSV-1 latency is crucial for understanding persistent viral infections and developing therapeutic strategies.

Purpose of the Study:

• To develop a novel in vitro model for studying HSV-1 latency using human neurons derived from embryonic stem cells.
• To establish a system that recapitulates key aspects of HSV-1 latency and reactivation in a human-relevant context.
• To provide a more manipulable model with access to molecular tools for studying HSV-1 latency.

Main Methods:

• Human neurons were differentiated from an NIH-approved embryonic stem cell line.
• Neurons were infected with wild-type HSV-1 at low doses with antivirals (acyclovir, interferon-α) to establish latency.
• Latency was characterized by the absence of viral replication and late gene expression, but presence of latency-associated transcript (LAT) RNA.
• Reactivation was induced using sodium butyrate after antiviral withdrawal.

Main Results:

• The human stem cell-derived neurons supported HSV-1 replication and established a non-productive infection state mimicking latency.
• Accumulation of latency-associated transcript (LAT) RNA was observed during the latency phase.
• Reactivation with production of infectious virus was successfully induced upon treatment with sodium butyrate.
• The model demonstrated species-specificity, suitable for studying an exclusively human virus.

Conclusions:

• Human stem cell-derived neurons offer a powerful and manipulable model for studying HSV-1 latency and reactivation.
• This model overcomes limitations of animal models by providing a human cellular context and enabling extensive molecular investigation.
• The developed system holds significant potential for advancing research into HSV-1 pathogenesis and therapeutic interventions.