The regulators of BCR signaling during B cell activation.

B lymphocytes produce antibodies under the stimulation of specific antigens, thereby exerting an immune effect. B cells identify antigens by their surface B cell receptor (BCR), which upon stimulation, directs the cell to activate and differentiate into antibody generating plasma cells. Activation of B cells via their BCRs involves signaling pathways that are tightly controlled by various regulators. In this review, we will discuss three major BCR mediated signaling pathways (the PLC-γ2 pathway, PI3K pathway and MAPK pathway) and related regulators, which were roughly divided into positive, negative and mutual-balanced regulators, and the specific regulators of the specific signaling pathway based on regulatory effects.

The Role of Mst1 in Lymphocyte Homeostasis and Function.

The Hippo pathway is an evolutionarily conserved pathway crucial for regulating tissue size and for limiting cancer development. However, recent work has also uncovered key roles for the mammalian Hippo kinases, Mst1/2, in driving appropriate immune responses by directing T cell migration, morphology, survival, differentiation, and activation. In this review, we discuss the classical signaling pathways orchestrated by the Hippo signaling pathway, and describe how Mst1/2 direct T cell function by mechanisms not seeming to involve the classical Hippo pathway. We also discuss why Mst1/2 might have different functions within organ systems and the immune system. Overall, understanding how Mst1/2 transmit signals to discrete biological processes in different cell types might allow for the development of better drug therapies for the treatments of cancers and immune-related diseases.

The Coordination Between B Cell Receptor Signaling and the Actin Cytoskeleton During B Cell Activation.

B-cell activation plays a crucial part in the immune system and is initiated via interaction between the B cell receptor (BCR) and specific antigens. In recent years with the help of modern imaging techniques, it was found that the cortical actin cytoskeleton changes dramatically during B-cell activation. In this review, we discuss how actin-cytoskeleton reorganization regulates BCR signaling in different stages of B-cell activation, specifically when stimulated by antigens, and also how this reorganization is mediated by BCR signaling molecules. Abnormal BCR signaling is associated with the progression of lymphoma and immunological diseases including autoimmune disorders, and recent studies have proved that impaired actin cytoskeleton can devastate the normal activation of B cells. Therefore, to figure out the coordination between the actin cytoskeleton and BCR signaling may reveal an underlying mechanism of B-cell activation, which has potential for new treatments for B-cell associated diseases.