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Studying Organelle Dynamics in B Cells During Immune Synapse Formation
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Studying Organelle Dynamics in B Cells During Immune Synapse Formation

Published on: June 1, 2019

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Polarity protein Par3 controls B-cell receptor dynamics and antigen extraction at the immune synapse

Anne Reversat1, Maria-Isabel Yuseff2, Danielle Lankar1

  • 1INSERM U932, Institut Curie, Centre de Recherche, 75005 Paris, France.

Molecular Biology of the Cell
|January 30, 2015
PubMed

Insights

The polarity protein Par3 coordinates B-cell receptor (BCR) microcluster transport and microtubule-organizing center (MTOC) polarization. This ensures efficient antigen processing and presentation to T-lymphocytes.

Area of Science:

  • Immunology
  • Cell Biology
  • Molecular Biology

Background:

  • B-cell receptor (BCR) engagement with antigens forms an immune synapse for antigen uptake.
  • Antigen processing involves early dynein-dependent transport and later microtubule-organizing center (MTOC) polarization.
  • Coordination between early and late synaptic events in B-cells remains unclear.

Purpose of the Study:

  • To investigate the role of the polarity protein Par3 in coordinating B-cell immune synapse formation.
  • To determine how Par3 influences antigen internalization, processing, and presentation.

Main Methods:

  • Studied B-cell immune synapse formation in response to surface-tethered antigens.
  • Investigated the role of Par3 in dynein recruitment, microcluster gathering, and MTOC polarization.
  • Assessed the impact of Par3 on lysosome exocytosis and T-lymphocyte antigen presentation.

Main Results:

  • Par3 promotes BCR-antigen microcluster gathering at the immune synapse.
  • Par3 facilitates MTOC polarization and lysosome exocytosis by enhancing local dynein recruitment.
  • Par3 is essential for efficient antigen presentation to T-lymphocytes.

Conclusions:

  • Par3 acts as a crucial coordinator of early and late events at the B-cell immune synapse.
  • Par3 links antigen microcluster transport with MTOC polarization for effective antigen processing.
  • Par3 is vital for B-cells to extract and present immobilized antigens to T-cells.

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