Lipopolysaccharides: From Erinyes to Charites

Following the discovery of endotoxins by Richard Pfeiffer, such bacterial product was associated to many severe disorders produced by an overwhelming inflammatory response and often resulting in endotoxic shock and multiple organ failure. However, recent clinical and basic sciences investigations claimed some beneficial roles of typical as well as atypical endotoxins. The aim of this paper is to focus on recent data supporting a beneficial activity of both typical and atypical endotoxins. Such novel perspective looks promising for development of new drugs for prevention and therapy of several human diseases

Virological Mechanisms in the Coinfection between HIV and HCV

Due to shared transmission routes, coinfection with Hepatitis C Virus (HCV) is common in patients infected by Human Immunodeficiency Virus (HIV). The immune-pathogenesis of liver disease in HIV/HCV coinfected patients is a multifactorial process. Several studies demonstrated that HIV worsens the course of HCV infection, increasing the risk of cirrhosis and hepatocellular carcinoma. Also, HCV might increase immunological defects due to HIV and risk of comorbidities. A specific cross-talk among HIV and HCV proteins in coinfected patients modulates the natural history, the immune responses, and the life cycle of both viruses. These effects are mediated by immune mechanisms and by a cross-talk between the two viruses which could interfere with host defense mechanisms. In this review, we focus on some virological/immunological mechanisms of the pathogenetic interactions between HIV and HCV in the human host

Procalcitonin neutralizes bacterial LPS and reduces LPS-induced cytokine release in human peripheral blood mononuclear cells

Abstract Background Procalcitonin (PCT) is a polypeptide with several cationic aminoacids in its chemical structure and it is a well known marker of sepsis. It is now emerging that PCT might exhibit some anti-inflammatory effects. The present study, based on the evaluation of the in vitro interaction between PCT and bacterial lipopolisaccharide (LPS), reports new data supporting the interesting and potentially useful anti-inflammatory activity of PCT. Results PCT significantly decreased (p Salmonella typhimurium (rough chemotype) and Escherichia coli (smooth chemotype). Subsequently, the in vitro effects of PCT on LPS-induced cytokine release were studied in human peripheral blood mononuclear cells (PBMC). When LPS was pre-incubated for 30 minutes with different concentrations of PCT, the release of interleukin-10 (IL-10) and tumor necrosis factor alpha (TNFα) by PBMC decreased in a concentration-dependent manner after 24 hours for IL-10 and 4 hours for TNFα. The release of monocyte chemotactic protein-1 (MCP-1) exhibited a drastic reduction at 4 hours for all the PCT concentrations assessed, whereas such decrease was concentration-dependent after 24 hours. Conclusions This study provides the first evidence of the capability of PCT to directly neutralize bacterial LPS, thus leading to a reduction of its major inflammatory mediators.</p