Functional gap junctions accumulate at the immunological synapse and contribute to T cell activation

Area of Science:

• Immunology
• Cell Biology
• Molecular Biology

Background:

• Gap junctions (GJs) mediate intercellular communication via linked hemichannels.
• Connexin 43 (Cx43) is the primary GJ protein in the immune system.

Purpose of the Study:

• To investigate the role of Cx43 in T cell priming and activation at the immunological synapse.
• To determine if Cx43 functions as GJs and/or hemichannels in T cell-dendritic cell interactions.

Main Methods:

• Utilized human and mouse models for T cell priming studies.
• Employed fluorescence recovery after photobleaching and Cx43-specific inhibitors.
• Investigated Cx43 recruitment to the immunological synapse, requiring intact actin cytoskeleton.

Main Results:

• Cx43 was recruited to the immunological synapse as GJs and hemichannels in an antigen-specific and time-dependent manner.
• Intercellular communication between T cells and dendritic cells was shown to be bidirectional and Cx43-mediated.
• Silencing Cx43 or inhibiting GJ docking impaired T cell intracellular Ca(2+) responses and cytokine release.

Conclusions:

• Cx43 is a key functional component of the immunological synapse.
• GJs and hemichannels play a crucial role in coordinating dendritic cell-T cell signaling for T cell activation.