IL6 and bacterial infectious disease: LPS is considered as one of the key contributing factor for systemic inflammatory responses [28] as it has inherent property to induce macrophages to generate pathophysiological factors, such as inflammatory cytokines (TNF-α, IL-6 and COX-2 etc.), free radicals, such as NO and critical proteins related with bacterial infection and inflammation, such as CRP [46]–[48].