Related Experiment Video
Updated: May 15, 2026
Imaging of HIV-1 Envelope-induced Virological Synapse and Signaling on Synthetic Lipid Bilayers
Published on: March 8, 2012
In vivo imaging of virological synapses
Xaver Sewald1, David G Gonzalez, Ann M Haberman
1Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut 06510, USA.
Insights
Researchers visualized retroviral spreading in living mice, confirming that infected B cells form virological synapses with other leukocytes in lymph nodes. This validates the concept of in vivo virological synapses for retrovirus transmission.
Area of Science:
- Virology
- Immunology
- Cell Biology
Background:
- Retroviruses like HIV and murine leukemia virus are thought to spread through virological synapses.
- In vitro studies show infected cells form stable contacts with uninfected cells, supporting this model.
- The existence of virological synapses in vivo remains unconfirmed.
Purpose of the Study:
- To investigate the in vivo existence and characteristics of virological synapses during retroviral infection.
- To visualize the direct cell-to-cell spread of Friend murine leukemia virus in a living organism.
Main Methods:
- Intravital microscopy was employed to observe B cell-leukocyte interactions in the lymph nodes of living mice infected with Friend murine leukemia virus.
- Analysis focused on identifying and characterizing cell-cell contacts indicative of virological synapses.
Main Results:
- A subpopulation of infected B cells forming virological synapses with uninfected leukocytes was identified in vivo.
- These in vivo virological synapses demonstrated dependence on viral envelope glycoprotein expression.
- Viral capsid polarization to the cell-cell interface was a key characteristic of these structures.
Conclusions:
- The study validates the concept of virological synapses as a mechanism for in vivo retroviral spread.
- Intravital imaging is established as a powerful tool for direct visualization of retroviral dissemination in living animals.
Abstract:
Retroviruses such as the human immunodeficiency virus, human T-cell lymphotropic virus and murine leukaemia virus are believed to spread via sites of cell-cell contact designated virological synapses. Support for this model is based on in vitro evidence in which infected cells are observed to specifically establish long-lived cell-cell contact with uninfected cells. Whether virological synapses exist in vivo is unknown. Here we apply intravital microscopy to identify a subpopulation of B cells infected with the Friend murine leukaemia virus that form virological synapses with uninfected leucocytes in the lymph node of living mice. In vivo virological synapses are, like their in vitro counterpart, dependent on the expression of the viral envelope glycoprotein and are characterized by a prolonged polarization of viral capsid to the cell-cell interface. Our results validate the concept of virological synapses and introduce intravital imaging as a tool to visualize retroviral spreading directly in living mice.
