- Human pathology

Home > B. Cellular pathology > programmed cell death

programmed cell death

Saturday 29 December 2018


Definition : Programmed cell death (or PCD) is the death of a cell in any form, mediated by an intracellular program.

PCD is carried out in a biological process, which usually confers advantage during an organism’s life-cycle. For example, the differentiation of fingers and toes in a developing human embryo occurs because cells between the fingers apoptose; the result is that the digits are separate. PCD serves fundamental functions during both plant and animal tissue development.

The apoptosis and the autophagy are the 2 forms of programmed cell death, but necrosis was long seen as a non-physiological process that occurs as a result of infection or injury.

A form of programmed necrosis, called necroptosis , has been recognized as an alternative form of programmed cell death. It is hypothesized that necroptosis can serve as a cell-death backup to apoptosis when the apoptosis signaling is blocked by endogenous or exogenous factors such as viruses or mutations.

Other types of regulated necrosis have been discovered as well, which share several signaling events with necroptosis and apoptosis.