We also examined whether isolated exosomes could re-enter cells and thereby play roles in intercellular processes or events. Methods AZD9668 in vitro and Results: Groups were established of healthy C57BL/6 mice and mice with acute liver failure (ALF) induced by a single i.p. LD50 dose of 500mg/kg acetaminophen (APAP). The extent of injury was established by liver tests and histology. Primary mouse hepatocytes were

isolated by collagenase perfusion and cultured on collagen and additives with IC50 dose of 20 mM APAP. Cytotoxicity was monitored by MTT assay. Hepatic injury was ameliorated by G-CSF treatment. Exosomes were isolated by established methods from blood sera and culture medium. miRNA samples were prepared from liver, hepato-cytes and exosomes including healthy controls and APAP- or APAP+GCSF-treated conditions. Small RNA libraries were prepared with commercial kits and next-generation sequencing was performed with the Ion Torrent platform followed by comprehensive bioinformatics analysis. The miRNA profiles of intact tissue, cultured hepatocytes

and exosomes differed markedly, indicating significant divergences at both quanti tative and qualitative levels. These differences were amplified after APAP-induced injury. Remarkably, while miRNA profiles of healthy and GCSF-treated liver samples re-converged along pattern similarity, profiles of exosome miRNA remained different and included multiple species of unknown impact. We found exosomes were avidly incorporated Ibrutinib order in hepatocytes, including after i.v. injection into DPPIV- mice or after culture with hepatocytes, where DPPIV+ or dye-labeled exosomes were identified by staining methods. Moreover, in MTT assays of APAP cytotoxicity with responder

mouse or human hepato-cytes, exosomes from healthy cells, but not from APAP-treated cells proved cytoprotective. Conclusions: Hepatic exosomal content altered after injury and offers opportunities for correlation with cell type-specific changes and therapeutic MCE responses. Moreover, differences in cytotoxic outcomes after incorporation of healthy exosomes indicate these may serve other relevant roles for cell-cell communication in health or disease. Disclosures: The following people have nothing to disclose: Yogeshwar Sharma, Tatyana Tchaikovskaya, Preeti Viswanathan, David B. Rhee, Pilib O Broin, Tatyana Gor-bacheva, Alexander Y. Maslov, Aaron Golden, Sanjeev Gupta BACKGROUND/AIM: Heat shock factor 1 (HSF1), is the master regulator of genes encoding molecular chaperones and is involved in cellular processes such as stress response, cell differentiation and carcinogenesis. Recent studies identified a HSF1-regulated transcriptional program specific to high malignancy and distinct from the classical HSF1-induced heat shock response. We have investigated the expression of HSF1 during tumour formation and after Radiofrequency Ablation (RFA) in vivo.