Nonalcoholic fatty liver disease is increasing in prevalence. It can be subdivided into nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH). Five to twenty percent of cases progress from NAFL to NASH. Increased hepatic Th17 cells and IL-17 expression were observed in NASH mice and patients, respectively. We analyzed CD4+ effector T cells and regulatory T cells (Tregs) from peripheral blood and livers of NAFL and NASH patients. A total of 51 NAFL patients, 30 NASH patients, 31 nonalcoholic fatty liver disease patients (without histology), and 43 healthy controls were included. FACS analysis was performed on PBMCs and intrahepatic lymphocytes. Compared with healthy controls, a lower frequency of resting Tregs (rTregs; CD4+CD45RA+CD25++) and higher frequencies of IFN-γ+ and/or IL-4+ cells were detected among CD4+ T cells of peripheral blood in NASH, and to a lesser degree in NAFL. In hepatic tissue, NAFL to NASH progression was marked by an increase in IL-17+ cells among intrahepatic CD4+ T cells. To define immunological parameters in peripheral blood to distinguish NAFL from NASH, we calculated different ratios. Th17/rTreg and Th2/rTreg ratios were significantly increased in NASH versus NAFL. The relevance of our findings for NASH pathogenesis was highlighted by the normalization of all of the changes 1 y after bariatric surgery. In conclusion, our data indicate that NAFL patients show changes in their immune cell profile compared with healthy controls. NAFL to NASH progression is marked by an increased frequency of IL-17+ cells among intrahepatic CD4+ T cells and higher Th17/rTreg and Th2/rTreg ratios in peripheral blood.

Background Intestinal microbiota and their metabolites (e.g. short-chain fatty acids (SCFAs)) may influence nonalcoholic fatty liver disease (NAFLD). Objective The objective of this article is to analyze gut bacterial diversity together with fecal SCFA concentrations and immunophenotyping of peripheral blood in histology-proven NAFLD patients. Methods Thirty-two NAFLD patients (14 nonalcoholic fatty liver (NAFL), 18 nonalcoholic steatohepatitis (NASH)) and 27 healthy controls (HCs)) were included in this study. Bacterial communities in feces were profiled by 16S ribosomal RNA gene sequencing of the V3–V4 region. Fecal SCFA levels were analyzed by high-performance liquid chromatography. Fluorescence-activated cell sorting analysis was performed of peripheral blood mononuclear cells. Results NASH patients were characterized by higher abundance of Fusobacteria and Fusobacteriaceae compared to NAFL and HCs. Conforming to our finding that NAFLD patients had higher fecal acetate and propionate levels, taxonomical differences of fecal bacteria were dominated by SCFA-producing bacteria. Higher fecal propionate and acetate levels were associated with lower resting regulatory T-cells (rTregs) (CD4+CD45RA+CD25++) as well as higher Th17/rTreg ratio in peripheral blood as immunological characteristics of NASH patients. Conclusions NASH patients are characterized by a different gut microbiome composition with higher fecal SCFA levels and higher abundance of SCFA-producing bacteria in NAFLD. These changes are associated with immunological features of disease progression. Our data suggest an important role of the intestinal microbiome and immunomodulatory bacterial metabolites in human NAFLD.

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ObjectivesLiver biopsies are the current gold standard in non-alcoholic steatohepatitis (NASH) diagnosis. Their invasive nature, however, still carries an increased risk for patients’ health. The development of non-invasive diagnostic tools to differentiate between bland steatosis (NAFL) and NASH remains crucial. The aim of this study is the evaluation of investigated circulating microRNAs in combination with new targets in order to optimize the discrimination of NASH patients by non-invasive serum biomarkers.MethodsSerum profiles of four microRNAs were evaluated in two cohorts consisting of 137 NAFLD patients and 61 healthy controls. In a binary logistic regression model microRNAs of relevance were detected. Correlation of microRNA appearance with known biomarkers like ALT and CK18-Asp396 was evaluated. A simplified scoring model was developed, combining the levels of microRNA in circulation and CK18-Asp396 fragments. Receiver operating characteristics were used to evaluate the potential of discriminating NASH.ResultsThe new finding of our study is the different profile of circulating miR-21 in NASH patients (p<0.0001). Also, it validates recently published results of miR-122 and miR-192 to be differentially regulated in NAFL and NASH. Combined microRNA expression profiles with CK18-Asp396 fragment level scoring model had a higher potential of NASH prediction compared to other risk biomarkers (AUROC = 0.83, 95% CI = 0.754–0.908; p<0.001). Evaluation of score model for NAFL (Score = 0) and NASH (Score = 4) had shown high rates of sensitivity (91%) and specificity (83%).ConclusionsOur study defines candidates for a combined model of miRNAs and CK18-Asp396 levels relevant as a promising expansion for diagnosis and in turn treatment of NASH.

A modified Pouchot AOSD activity score including elevated serum ferritin levels was more useful to confirm the diagnosis of AOSD compared to patients with sepsis. Elevated serum cytokines correlate with inflammation but are of limited use to differentiate between active AOSD and bacterial sepsis.