The B cell receptor signalling pathway controls B-cell fate and function. Reprinted from with permission from Wiley. BTK, Bruton’s tyrosine kinase; IKK, IκB Kinase MAPK, mitogen-activated protein kinase; NFκB, nuclear factor κB; PI3Kδ, phosphoinositide 3-kinase; PIP2, phosphatidylinositol 4,5 bisphosphate; PIP3, phosphatidylinositol 3,4,5 triphosphate; PKC, protein kinase C; PLCγ2, phospholipase C γ2.