Expanding Insights: Harnessing Expansion Microscopy for Super-Resolution Analysis of HIV-1-Cell Interactions

Area of Science:

• Virology
• Cell Biology
• Microscopy

Background:

• Expansion microscopy offers high-resolution imaging by physically expanding samples.
• Its application in virology, particularly for HIV-1, remains underexplored.
• Understanding HIV-1 nuclear events requires advanced imaging techniques.

Purpose of the Study:

• To evaluate and characterize the ultrastructure expansion microscopy (U-ExM) protocol for HIV-1 research.
• To enable visualization of post-entry stages of the HIV-1 life cycle, focusing on nuclear events.
• To assess U-ExM's efficacy in different cell types, including HIV-1 reservoirs.

Main Methods:

• Applied the U-ExM protocol, achieving approximately four-fold sample expansion.
• Utilized U-ExM on various cell types: cell-culture-adapted and primary CD4+ T-cells, and monocyte-derived macrophages.
• Performed high-resolution imaging to visualize HIV-1 nuclear events and cellular structures.

Main Results:

• U-ExM demonstrated robust sample expansion and preservation across diverse cell types.
• Nuclear bodies and chromatin landscape were well-preserved, facilitating detailed HIV-1-cell interaction studies.
• Distinct HIV-1 capsid assemblies were visualized within infected cell nuclei, and U-ExM detected masked targets.

Conclusions:

• U-ExM is a valuable tool for high-resolution imaging in virology.
• The protocol enables detailed investigation of HIV-1 nuclear events and virus-host interactions.
• U-ExM enhances spatial resolution, offering new insights into the HIV-1 life cycle.