TLR4 and pneumonia: Finally, the activated complex LPS/MD2/TLR4 initiates the intracellular signalling pathway.3 TLR4 antibodies, inhibitors or antagonists which can affect the acetylation, dimerization or/and the recognition of ligands or receptors on TLR4 may inhibit the activation of downstream signalling, suggesting a strategy for pneumonia therapy via targeting TLR4 signalling.