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Updated: Apr 28, 2026
A TIRF Microscopy Technique for Real-time, Simultaneous Imaging of the TCR and its Associated Signaling Proteins
Published on: March 22, 2012
The tipping points in the initiation of B cell signalling: how small changes make big differences
1Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852, USA. spierce@niaid.nih.gov
Insights
New imaging reveals how B cell receptors (BCRs) initiate signaling upon antigen binding. This provides molecular insights into B cell activation, antigen discrimination, and potential causes of B cell cancers.
Area of Science:
- Immunology
- Cell Biology
- Molecular Biology
Background:
- B cell activation is initiated by antigen binding to B cell receptors (BCRs).
- Signaling cascades triggered by BCR engagement lead to B cell activation.
- Understanding early signaling events is crucial for B cell biology and disease.
Purpose of the Study:
- To elucidate the molecular events initiating B cell receptor (BCR) signaling immediately after antigen engagement.
- To provide a molecular basis for key B cell functions like antigen affinity discrimination and class switching.
- To gain insights into the origins of B cell-associated tumorigenesis.
Main Methods:
- High-resolution live-cell imaging techniques were employed.
- Real-time observation of molecular events following BCR engagement with antigen.
Main Results:
- Detailed temporal sequence of molecular events initiating BCR signaling has been observed.
- Mechanisms underlying antigen affinity discrimination by B cells are being elucidated.
- Early signaling events provide context for B cell class switching and tumorigenesis.
Conclusions:
- High-resolution live-cell imaging offers unprecedented insight into BCR signaling initiation.
- Understanding early BCR signaling events is fundamental to adaptive immunity.
- These findings may inform therapeutic strategies for B cell malignancies.
Abstract:
B cells are selected by the binding of antigen to clonally distributed B cell receptors (BCRs), triggering signalling cascades that result in B cell activation. With the recent application of high-resolution live-cell imaging, we are gaining an understanding of the events that initiate BCR signalling within seconds of its engagement with antigen. These observations are providing a molecular explanation for fundamental aspects of B cell responses, including antigen affinity discrimination and the value of class switching, as well as insights into the underlying causes of B cell tumorigenesis. Advances in our understanding of the earliest molecular events that follow antigen binding to the BCR may provide a general framework for the initiation of signalling in the adaptive immune system.
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