Differentiatie van gemeenschappelijke myeloïde voorlopercellen

Common myeloid progenitors or CMPs undergo multiple cell divisions before differentiating into granulocytes or phagocytes .

In response to an allergy or an infection, endothelial cells and fibroblasts release inflammatory cytokines called colony-stimulating factors or CSFs into the bloodstream.

At least four different types of CSFs participate in distinct combinations to help the progenitors divide and commit to specific cell types.

For example, during parasitic infection, interleukin 3 and GM CSF help CMPs differentiate into eosinophils that digest the parasite.

In contrast, granulocyte-CSF and macrophage-CSF released in response to a bacterial infection produce neutrophils and monocytes. Monocytes mature into macrophages, which along with neutrophils, phagocytose the invading bacteria.

Once the infection is cleared and CSF concentration drops, neutrophils die by apoptosis within a few days, while the macrophages continue to survive for months, circulating in the blood.