Apoptosis as a scaffold for building up the B cell repertoire

Control of cell number is determined by a balance between cell proliferation and cell death, both of which are highly regulated processes, with numerous checks and balances. Cells control their own death through activation of an internally coded suicide program that, when activated, initiates a characteristic form of cell death called apoptosis. This type of regulation allows elimination of cells that have been produced in excess, that have developed improperly, or that have sustained genetic damage. Apoptosis is, therefore, the most common physiological form of cell death and occurs during embryonic development, tissue remodeling, immune regulation, cell activation and tumor regression.