Assessment of haemostasis in patients with cirrhosis: Relevance of the ROTEM tests?: A prospective, cross-sectional study.

BACKGROUND: In patients with cirrhosis, decreased rotational thromboelastometry (ROTEM) parameters suggest hypocoagulability secondary to liver dysfunction. However, observed normal or increased thrombin generation suggests preserved haemostasis and/or a procoagulant state. The correlated levels of both coagulation factors and inhibitors also support preserved haemostasis. OBJECTIVE: The objective of this study is to investigate the correlation between three specific approaches of haemostasis (ROTEM, thrombin generation and coagulation factors/inhibitors) on the same plasma sample from patients with cirrhosis. DESIGN: A prospective, observational study. SETTING: Single university hospital. PARTICIPANTS: Forty patients with cirrhosis. INTERVENTION: Measurement of the following factors: model for end-stage liver disease (MELD) scores; ROTEM maximum clot firmness (ROTEM-MCF) in EXTEM, INTEM, FIBTEM assays; fibrinogen; factors V and VIII; von Willebrand factor; protein C; protein S; antithrombin; and the thrombin generation test (TGT) enabling the calculation of endogenous thrombin potential without and with thrombomodulin, and the ratio of endogenous thrombin potential with-to-without thrombomodulin (regarded as an index of hypercoagulability). RESULTS: ROTEM-MCF values were distributed within the normal and hypocoagulation ranges; were correlated to variations in factor V, fibrinogen, protein C and S and antithrombin; and were inversely correlated to MELD scores (ρ > 0.5; P < 0.05). Levels of von Willebrand factor were above normal and were not correlated with any other factor levels. After addition of thrombomodulin, endogenous thrombin potential values were distributed within or above normal values. Factor V variation was correlated to the ratio of endogenous thrombin potential with-to-without thrombomodulin. CONCLUSION: ROTEM indicated hypocoagulability correlated to liver dysfunction. In contrast, the TGT indicated a preserved or even increased coagulation profile (which was supported by the correlation between coagulant factors and inhibitors) and a potential for hypercoagulability inversely correlated to the degree of liver dysfunction. ROTEM may not be appropriate for haemostasis assessment in patients with liver cirrhosis and could lead to the unnecessary transfusion of fresh frozen plasma. TRIAL REGISTRATION: S.C. 3024 - ID RCB: 2012-A01728-35.

Genetic and pharmacological inactivation of the purinergic P2RX7 receptor dampens inflammation but increases tumor incidence in a mouse model of colitis-associated cancer.

Colitis-associated cancer (CAC) is a complication of inflammatory bowel disease (IBD). Binding of extracellular ATP to the purinergic receptor P2RX7 has emerged as a critical event in controlling intestinal inflammation, acting to limit elevation of proinflammatory mast cells and cytokines and promote survival of regulatory T cells (Treg) and enteric neurons. In this study, we investigated the effect of P2RX7 blockade in an established mouse model of CAC. Using genetic and pharmacologic tools, we found unexpectedly that while P2RX7 mediated inflammatory responses, it also acted at an early time to suppress CAC development. P2RX7 blockade enhanced proliferation of intestinal epithelial cells and protected them from apoptosis. The proliferative effects of P2RX7 blockade were associated with an increased production of TGFß1 that was sufficient to stimulate the proliferation of intestinal epithelial cells. Finally, P2RX7 blockade also altered immune cell infiltration and promoted Treg accumulation within lesions of the digestive system. Taken together, our findings reveal an unexpected role for P2RX7 in preventing CAC, suggesting cautions in the use of P2RX7 inhibitors to treat IBD given the possibility of increasing risks CAC as a result.

HIF1A regulates xenophagic degradation of adherent and invasive Escherichia coli (AIEC).

The hypoxia inducible transcription factor HIF1 activates autophagy, a general catabolic pathway involved in the maintenance of cellular homeostasis. Dysfunction in both autophagy and HIF1 has been implicated in an increasing number of human diseases, including inflammatory bowel disease (IBD), such as Crohn disease (CD). Adherent invasive E. coli (AIEC) colonize ileal mucosa of CD patients and strongly promote gastrointestinal inflammatory disorders by activation of HIF-dependent responses. Here, we aim to characterize the contribution of HIF1 in xenophagy, a specialized form of autophagy involved in the degradation of intracellular bacteria. Our results showed that endogenous HIF1A knockdown increased AIEC survival in intestinal epithelial cells. We demonstrate that the increase in survival rate correlates with a dramatic impairment of the autophagic flux at the autolysosomal maturation step. Furthermore, we show that AIEC remained within single-membrane LC3-II-positive vesicles and that they were unable to induce the phosphorylation of ULK1. These results suggested that, in the absence of HIF1A, AIEC were found within LC3-associated phagosomes. Using blocking antibodies against TLR5 and CEACAM6, the 2 well-known AIEC-bound receptors, we showed that downstream receptor signaling was necessary to mediate ULK1 phosphorylation. Finally, we provide evidence that HIF1 mediates CEACAM6 expression and that CEACAM6 is necessary to recruit ULK1 in a bacteria-containing signaling hub. Collectively, these results identify a new function for HIF1 in AIEC-dedicated xenophagy, and suggest that coactivation of autophagy and HIF1A expression may be a potential new therapy to resolve AIEC infection in CD patients.