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Published on: January 20, 2019
The endocytic adaptor Eps15 controls marginal zone B cell numbers
Benedetta Pozzi1, Stefania Amodio, Caterina Lucano
1IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy.
Plos One
|December 11, 2012
Summary
The endocytic adaptor protein Eps15 regulates B-cell lymphopoiesis in mammals. Eps15 knockout mice exhibit increased numbers of splenic marginal zone B cells, indicating a role in B-cell development.
Area of Science:
- Immunology
- Cell Biology
- Molecular Biology
Background:
- Eps15 is an endocytic adaptor protein crucial for clathrin-mediated endocytosis.
- Its absence in invertebrates causes defects in synaptic vesicle recycling and synapse formation.
- The function of Eps15 in mammalian immune cells remained largely unexplored.
Purpose of the Study:
- To investigate the role of Eps15 in mammalian physiology, particularly in the immune system.
- To determine the impact of Eps15 deficiency on hematopoietic precursor cells and B-cell development.
Main Methods:
- Generation and large-scale phenotyping of Eps15-knockout (Eps15-KO) mice.
- Competitive and reverse bone marrow transplantation assays.
- Flow cytometry (FACS) analysis of immune cell populations.
Main Results:
- Eps15-KO mice displayed no overt disease or neurological deficits but showed altered blood parameters indicating an immunological defect.
- Eps15-KO hematopoietic precursor cells showed enhanced repopulation capacity.
- A significant 2-fold increase in splenic marginal zone (MZ) B cell numbers was observed in Eps15-KO mice, regulated in a cell-autonomous manner.
- Transitional and pre-MZ B cell numbers were unaffected, and the increase was independent of BCR signaling or Notch activity.
Conclusions:
- The endocytic adaptor protein Eps15 plays a critical role in regulating B-cell lymphopoiesis in mammals.
- Eps15 specifically influences the development and maintenance of marginal zone B cells.
- These findings reveal a novel function for Eps15 beyond its established role in endocytosis.
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