Viewing the antigen‐induced initiation of B‐cell activation in living cells

@article{Tolar2008ViewingTA,
  title={Viewing the antigen‐induced initiation of B‐cell activation in living cells},
  author={Pavel Tolar and Hae Won Sohn and Susan K. Pierce},
  journal={Immunological Reviews},
  year={2008},
  volume={221}
}
Summary: The binding of antigen to the B‐cell receptor (BCR) induces BCR clustering and signaling cascades that lead to the activation of a variety of genes associated with B‐cell activation. Over the last several years, our understanding of the molecular details of the BCR signaling pathways have been considerably advanced; what remains only poorly understood are the molecular events that initiate BCR clustering and how clustering leads to activation. Here, we review our progress using live… 

It's all about change: the antigen-driven initiation of B-cell receptor signaling.

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The molecular assembly and organization of signaling active B‐cell receptor oligomers

What is known about the initiation of the antigen‐driven BCR signal transduction in the newly emerging context of B‐cell recognition of antigens presented by antigen‐presenting cells in lymphoid tissues is described.

B cell activation involves nanoscale receptor reorganizations and inside-out signaling by Syk

Using a high-resolution proximity ligation assay to monitor the conformation of the BCR and its interactions with co-receptors at a 10–20 nm resolution, direct evidence is provided for the opening of BCR dimers during B cell activation and it is shown that upon binding Syk opens the receptor by an inside-out signaling mechanism that amplifies BCR signaling.

Actin‐mediated feedback loops in B‐cell receptor signaling

How actin remodels its organization and dynamics in close coordination with BCR signaling and how act in remodeling in turn amplifies the activation and subsequent downregulation process of B CR signaling, providing vital feedback for optimal BCR activation is discussed.

Monte Carlo study of B-cell receptor clustering mediated by antigen crosslinking and directed transport

It is shown that directed transport of BCRs is needed to drive the formation of large macroclusters, and a simple model of directed transport, where BCR molecules diffuse towards the largest cluster or towards a random BCR microcluster, which results in a single macrocluster of receptor molecules.

A Balance of Bruton’s Tyrosine Kinase and SHIP Activation Regulates B Cell Receptor Cluster Formation by Controlling Actin Remodeling

It is shown that both the stimulatory Bruton’s tyrosine kinase (Btk) and the inhibitory SHIP-1 are required for efficient BCR self-aggregation and a novel feedback loop between BCR signaling and the actin cytoskeleton is suggested.

The actin cytoskeleton coordinates the signal transduction and antigen processing functions of the B cell antigen receptor

How actin remodeling translates B CR signaling into rapid antigen uptake and processing while providing positive and negative feedback to BCR signaling is discussed.

The regulation of B cell activation by membrane damage and antigen density

It was discovered that BCR activation interferes with plasma membrane repair, while wounding inhibits BCR signaling and internalization by segregating BCRs from lipid rafts, and manipulations of molecular configuration and density can be applied to enhance the immunogenicity of vaccines.
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