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Updated: Aug 14, 2026
06:50
Mitochondrial Transfer Via Tunneling Nanotubes Between Mesenchymal Stem Cells and Retinal Pigment Epithelium In Vitro
Published on: October 4, 2024
Tunnel traffic: Import stress induces bidirectional mitochondrial transfer between cells
Konstanze F Winklhofer1,2, Johannes M Herrmann3
1Department of Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany.
The Journal of Cell Biology
|August 13, 2026
Summary
Stressed cells utilize tunneling nanotubes to transfer mitochondria. Distinct nanotubes facilitate either the export of damaged mitochondria or the import of healthy, energy-producing ones.
Area of Science:
- Cell Biology
- Mitochondrial Dynamics
- Intercellular Communication
Background:
- Cells under stress can exhibit altered mitochondrial function.
- Intercellular communication mechanisms are crucial for cellular homeostasis.
- Tunneling nanotubes (TNTs) are known conduits for material exchange between cells.
Purpose of the Study:
- To investigate the role of tunneling nanotubes in mitochondrial exchange during cellular stress.
- To differentiate the functions of various TNTs involved in mitochondrial transfer.
Main Methods:
- Live-cell imaging of mitochondrial dynamics.
- Fluorescence microscopy to track mitochondrial transfer.
- Functional assays to assess mitochondrial health and respiration.
Main Results:
- Two distinct types of tunneling nanotubes were identified.
- One type of TNT facilitates the export of dysfunctional mitochondria.
- A separate type of TNT enables the import of functional, respiration-active mitochondria.
Conclusions:
- Tunneling nanotubes play a critical role in managing mitochondrial health within cell populations.
- Cells can selectively transfer mitochondria via specialized TNTs to maintain viability.
- This intercellular mitochondrial exchange represents a novel mechanism for cellular adaptation to stress.
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