So it is exactly the Innate immunity.
The presence of infections is recognized by receptors for
a specific event called the Pathogen-Associated Molecular Patterns or the PAMPs.
These PAMPs are produced by microorganisms,
such as bacteria, or fungi and yeast.
The recognition of these PAMPs by myeloid cells is the first step of
a complex inflammatory reactions that characterizes the innate immune response.
So the Endotoxin Lipopolysaccharide is
a major component of the outer membranes of the Gram-negative bacteria,
which is the best known target of innate recognition and induce
a robust inflammatory response by phagocytes or phagocytic cells, if you want.
We have many other PAMPs such as Peptidoglycan and so LTA from
Gram-postive bacterias which are known common structural patterns that are
recognized by host germ lines encoded receptors and induce stimulation of
the nuclear factors called NF kappa B signaling pathways and cytokine synthesis.
An NF kappa B is certainly one of
the best known signaling factors that is associated with the inflammatory response.
You have a classical NF kappa B and you have a known Classical NF kappa B pathways.
And a Classical one is clearly taking place in macrophages, dendritic cells,
monocytes and the cells that are clearly
responsible for the innate immune response and you have
a Nonclassical cell cell interactions that are critical for
the T and B cells that developments which are involved in the adaptive immunity.
Then you have the T cells,
you have the antigens interacting with the TCR and
also you have other ligands such as the LT
for Lymphotoxin or BAFF for B-cells and
activating factors which activates B receptors in B cells.
But the Classical one is really the one which is
triggered by the cytokine we just mentioned before such as TNF,
Interleukin-1 and LPS or many other PAMPs.
They triggered the NF kappa B activation by interacting with specific receptors,
express on the surface of B cells such as
Interleukin-1 receptors and you have also the Toll-like receptors, the TLR.
These receptors engaged productions of NF kappa B via
series of adaptive proteins such as myD88,
TRAF 6 and TAB, TAK and TAB.
These are the proteins which will activate phosphorylation of the complex of IKK.
Once you have phosphorylation of IkB for example,
then you have activations of the NF kappa B,
essentially, the main factors which is p50 and p65.
Then, you have translocations of the nuclear factors,
these activate a wide varieties of genes,
target genes such as genes involved in inflammations,
genes involved in the receptors productions and anti-apoptosis genes as well.
Then, this is clearly taking place within minutes,
once the ligands has been triggered the receptors.