Inflammation is triggered in the innate immune
response by tissue myeloid cells, macrophages in peripheral tissue and
microglia in the nervous system, in response to microbial or endogenous danger
signals.
The plasticity of these cells developing into
pro-inflammatory M1 and anti-inflammatory M2 phenotypes is remarkable.
Polarization of macrophages depends on local environmental factors, especially
cytokines and growth factors.
Interferon-γ (IFN-γ) and bacterial
lipopolysaccharide together polarize macrophage into the M1 phenotype which produces reactive oxygen
species, nitric
oxide, and inflammatory cytokines such as tumor necrosis factor-α. However, NO
appears to play a negative role in M1 macrophage differentiation.
No comments:
Post a Comment