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Acute respiratory distress syndrome (ARDS) is a syndrome of acute respiratory failure caused by infection, trauma, shock, aspiration or drug reaction. The pathogenesis of ARDS is characterized as an unregulated inflammatory storm, which causes endothelial and epithelial layer damage, leading to alveolar fluid accumulation and pulmonary edema. Previous studies have shown the potential role of mesenchymal stem cells (MSC) in combating the inflammatory cascade by increasing the anti-inflammatory mediator interleukin-10 (IL-10). However, the involved mechanisms are unclear. Here we investigated whether a key immunomodulatory regulator, stanniocalcin-1 (STC-1), was secreted by MSC to activate phosphoinositide 3-kinase/protein kinase B (PI3K/AKT)/ mammalian target of rapamycin (mTOR) signaling pathway to increase IL-10 expression in alveolar macrophages. Lipopolysaccharide (LPS)-stimulated alveolar macrophages co-cultured with human umbilical mesenchymal stem cells (HUMSC) secreted high levels of IL-10. HUMSC co-cultured with alveolar macrophages expressed high STC-1 levels and increased PI3K, AKT and mTOR phosphorylation after LPS activation in alveolar macrophages. STC-1 knockdown in HUMSC decreased the phosphorylation of PI3K, AKT and mTOR and suppressed IL-10 expression in alveolar macrophages. Rapamycin (an mTOR inhibitor) reduced IL-10 secretion in alveolar macrophages. These results, together with our previous study and others, indicate that the PI3K/AKT/mTOR pathway is involved in the regulation of IL-10 production by STC-1 secreted by HUMSC in alveolar macrophages.

Tristetraprolin (TTP) is an RNA-binding protein which can bind to the AU-rich elements (AREs) at the 3'-untranslated region (3'-UTR) of target mRNA and promote mRNA deadenylation and degradation. We have shown in a previous study that TTP regulates tumor necrosis factor-α (TNF-α)-induced expression of intercellular adhesion molecule-1 (ICAM-1) and interleukin-8 (IL-8), both of whose mRNAs have AREs in the 3'-UTR, in human pulmonary microvascular endothelial cells (HPMEC) through destabilizing target mRNAs, nevertheless, the mechanism by which TTP promotes mRNA decay remains unclear. Observations have indicated that TTP can interact with CAF1 (CNOT7/hCAF1 in human), a subunit of the CCR4-NOT complex with deadenylase activity. Another study illustrated that TTP can directly bind to CNOT1, the scaffold subunit of the CCR4-NOT complex. The present study showed that TTP bound to the AREs of ICAM-1 and IL-8 mRNAs and was coimmunoprecipitated with intracellular ICAM-1 and IL-8 mRNAs. TTP, CNOT7 and CNOT1 were coimmunoprecipitated in HPMEC. CNOT7 silencing stabilized ICAM-1 and IL-8 mRNAs and increased ICAM-1 and IL-8 production following TNF-α stimulation. These results, together with our previous study, suggest that CNOT7/hCAF1 is involved in ICAM-1 and IL-8 regulation by TTP in HPMEC.

The aim of this study was to review our experience with living related liver transplantation (LRLT) for Wilson's disease. From January 2001 to July 2003 LRLT were performed in 18 patients with Wilson's disease, seven of whom had neurologic complications. The mean age of the patients was 13.5 +/- 2.3 years (range 6 to 20). Before transplantation all recipients displayed low serum ceruloplasmin levels (mean value = 118.4 +/- 32.6 mg/L). The serum ceruloplasmin levels increased to an average of 236.8 +/- 38.5 mg/L after LRLT at the latest evaluation, which ranged between 2 and 32 months after transplantation. A marked reduction in urinary copper excretion was observed in all recipients after transplantation. All recipients are alive and remain well. None have developed signs of recurrent Wilson's disease after a mean follow-up of 18.2 +/- 9.4 months (range 2 to 32 months). The donors were 17 mothers and one father of mean age 34.0 +/- 3.0 years (range 30 to 45 years). The serum ceruloplasmin levels were within normal limits in all donors (mean 226 +/- 27.8 mg/L). Two donors had biliary leakage and percutaneous drainage Grafts included four right lobes without the hepatic middle vein and 14 left lobe grafts with the middle vein. LRLT is a curative procedure for Wilson's disease presenting with fulminant hepatic failure and the others with end-stage hepatic insufficiency. After liver transplantation, the serum ceruloplasmin level increases to the normal range, urinary copper excretion decreases, and neurological manifestations improve to various extents.