User:Cfennell2016/sandbox

A progenitor cell is a unipotent, or sometimes oligopotent, cell that directs differentiation. Like a stem cell, progenitor cells specify into particular cell types, however they are the direct predecessors to these cell types, unlike stem cells. The main difference between stem cells and progenitor cells is that stem cells have self-renewal capability and they can replicate indefinitely. Progenitor cells have less freedom in regard to their differentiation capability, and they have a finite amount of divisions. There are different types of progenitor cells that specify particular fates. For example, Endothelial Progenitor Cells (EPCs) differentiate into Endothelial type cells.

The concept of progenitor cells is still evolving, therefore the exact definition is still being established.

Research
Progenitor cells have become a hub for research on a few different fronts. Current research on progenitor cells focuses on two different applications: regenerative medicine and cancer biology. Research on regenerative medicine has focused on progenitor cells, and stem cells, because their cellular senescence contributes largely to the process of aging. Research on cancer biology focuses on the impact of progenitor cells on cancer responses, and the way that these cells tie into the immune response.

The natural aging of cells, called their cellular senescence, is one of the main contributors to aging on an organismal level. There are a few different ideas to the cause behind why aging happens on a cellular level. Telomere length has been shown to positively correlate to longevity. Increased circulation of progenitor cells in the body has also positively correlated to increased longevity and regenerative processes. Endothelial Progenitor Cells (EPCs) are one of the main focuses of this field. They are valuable cells because they directly precede endothelial cells, but have characteristics of stem cells. These cells can produce differentiated cells to replenish the supply lost in the natural process of aging, which makes them a target for aging therapy research. This field of regenerative medicine and aging research is still currently evolving.

Recent studies have shown that Haematopoietic Progenitor Cells contribute to immune responses in the body. They have been shown to respond a range of pro-inflammatory cytokines. They also contribute to fighting infections by providing a renewal of the depleted resources caused by the stress of an infection on the immune system. Pro-inflammatory cytokines and other factors released in relation to infections will activate Haematopoietic Progenitor Cells to differentiate to replenish the lost resources.