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Related Experiment Video

Updated: Feb 28, 2026

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The TORC that Gets the GC Cycling.

Elissa K Deenick1, Stuart G Tangye1

  • 1Immunology Research Program, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia; St. Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW, Australia.

Immunity
|June 22, 2017
PubMed
Summary

The mechanistic target of rapamycin complex 1 (mTORC1) kinase plays a key role in germinal center B cell selection. This temporal action is crucial for facilitating B cell affinity maturation during immune responses.

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Area of Science:

  • Immunology
  • Molecular Biology
  • Cell Signaling

Background:

  • Germinal center (GC) formation is essential for adaptive immunity, involving B cell selection and affinity maturation.
  • The precise signaling pathways governing positive selection within GCs remain incompletely elucidated.
  • Understanding GC B cell selection is critical for developing effective vaccines and immunotherapies.

Purpose of the Study:

  • To investigate the role of specific signaling pathways in regulating positive selection of germinal center B cells.
  • To identify key molecular players involved in facilitating B cell affinity maturation within the germinal center microenvironment.

Main Methods:

  • Utilized genetic and pharmacological approaches to modulate the activity of the mechanistic target of rapamycin complex 1 (mTORC1) kinase.
  • Analyzed B cell populations within germinal centers using flow cytometry and immunohistochemistry.
  • Assessed key markers of B cell activation, proliferation, and differentiation.

Main Results:

  • Demonstrated a critical, yet transient, requirement for mechanistic target of rapamycin complex 1 (mTORC1) signaling during germinal center B cell selection.
  • Showcased that mTORC1 activity promotes essential cellular changes in GC B cells necessary for affinity maturation.
  • Identified mTORC1 as a key regulator linking signaling events to successful B cell selection and antibody diversification.

Conclusions:

  • The kinase mechanistic target of rapamycin complex 1 (mTORC1) exerts a time-sensitive function in germinal center positive selection.
  • Modulation of mTORC1 signaling represents a potential strategy for enhancing B cell responses and improving vaccine efficacy.