These extracellular protein-protein-interactions, in turn, result in dimerization of TIR-domain containing intracellular cytosolic parts of the TLR4 receptors leading to Myeloid differentiation primary response gene 88 (MyD88)- or TIR-domain-containing adapter-inducing interferon- (TRIF)-dependent downstream signalling (Molinaro et al., 2015) (Fig. 3A).