TLR4 and serum lipopolysaccharide activity: The translocated LPS are detected by CD14 and toll-like receptor 4 (TLR4), which causes the release of pro-inflammatory cytokines such as tumor necrosis factor alpha (TNFα), interferon alpha (IFNα), interferon-gamma (INFγ) and interleukins (IL1β or IL6), which can eventually result in endotoxemia [57] (Fig. 2).