SNX17 affects T cell activation by regulating TCR and integrin recycling

Area of Science:

• Immunology
• Cell Biology
• Molecular Biology

Background:

• T cell activation relies on endosomal receptor recycling for sustained signaling and antigen recognition.
• Sorting nexin 17 (SNX17) is a potential mediator of T cell receptor (TCR) transport, but its specific role is uncharacterized.

Purpose of the Study:

• To investigate the function of SNX17 in T cell receptor (TCR) and integrin recycling.
• To determine the role of SNX17 in T cell activation and immune synapse formation.

Main Methods:

• Immunofluorescence microscopy to assess SNX17 and TCR colocalization at the immune synapse.
• SNX17 knockdown experiments to evaluate effects on T cell-APC conjugation and surface receptor expression.
• Analysis of T cell receptor (TCR) and LFA-1 surface expression and recycling.

Main Results:

• SNX17 colocalizes with TCR at the immune synapse in T cell-APC conjugates.
• SNX17 knockdown reduces T cell-APC conjugate formation, surface expression of CD69, TCR, and LFA-1, and TCR recycling.
• The 4.1/ezrin/radixin/moesin domain of SNX17 is essential for TCR and LFA-1 trafficking.

Conclusions:

• SNX17 plays a significant role in maintaining surface levels of activating receptors and integrins.
• SNX17 is critical for optimal T cell activation at the immune synapse by facilitating receptor recycling.