Understanding of B Cell Receptor Signaling Through a Photo-Activatable Antigen Presentation System.

Antibody responses are initiated by the binding of antigens to cell surface expressed B cell receptors (BCRs) that trigger signaling cascades resulting in the activation of B cells. However, it has been difficult to study these cascades due to their fast, dynamic, and transient nature. Using a conventional antigen-presenting system, such as planar lipid bilayers (PLBs), the initial events during B cell activation have been difficult to be captured. Here, we describe the general procedures for the utilization of a photoactivatable antigen-presenting system in the combination with a high speed live cell imaging method to investigate the early activation events in the same B cells in response to antigen stimulation.