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Updated: Jun 26, 2026
07:55
An Improved Method to Isolate Mitochondrial Contact Sites
Published on: June 16, 2023
Mdivi-1-Sensitive Mitochondrial Remodeling Contributes to B Cell Immune Synapse Formation and Antigen Presentation
Juan Pablo Bozo1, Teemly Contreras1, Antonio Sánchez-Squella2
1Laboratory of Immune Cell Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile.
Cells
|June 25, 2026
Summary
Mitochondrial dynamics, specifically fission regulated by Drp1, are crucial for B cell immune synapse function. Inhibiting this process impairs antigen extraction and presentation, highlighting mitochondria
Area of Science:
- Immunology
- Cell Biology
- Mitochondrial Dynamics
Background:
- B cell activation involves forming an immune synapse (IS) for antigen processing and presentation.
- Mitochondria regulate cellular metabolism but their role in IS function is unclear.
Purpose of the Study:
- To investigate the influence of mitochondrial dynamics on antigen processing and presentation in B cells.
- To explore the role of Drp1-mediated mitochondrial fission in B cell immune synapse function.
Main Methods:
- Studied B cell receptor (BCR) engagement and its effect on mitochondrial dynamics.
- Utilized mdivi-1 to perturb Drp1-associated mitochondrial fission and assessed its impact on mitochondrial morphology, activity, and synaptic accumulation.
- Analyzed tubulin acetylation, lysosome trafficking, and lysosome-synaptic membrane fusion.
Main Results:
- BCR engagement rapidly phosphorylated the mitochondrial fission GTPase Drp1 at Ser616.
- Mdivi-1 treatment altered mitochondrial morphology, reduced activity, and decreased synaptic accumulation.
- Mdivi-1 treatment led to increased tubulin acetylation, lysosome retention, and reduced lysosome fusion, impairing antigen extraction and presentation.
Conclusions:
- Mitochondrial fission and activity, sensitive to mdivi-1, are linked to mitochondrial positioning, lysosomal trafficking, and exocytosis at the B cell IS.
- Mitochondrial dynamics play a significant role in efficient antigen extraction and presentation by B cells.
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