Altered Expression Profiles Of MicroRNAs In PBMC Of Acute-on-chronic Liver Failure Patients Caused By Hepatitis B Virus

Background MicroRNAs(miRNAs)are a set of small non-coding RNAs of22nucleotides(nt)．They were processed by the RNA polymerase II, nulear RNase III Droshaand Dicer. MiRNAs are known widespread in nature now.It was the sequentialdevelopment of the gene that miRNAs were first observed in C.elegans.Then far, over3,500miRNAs have been identified,with greater than450found in human.Presumally,about1%-3%genetic can encode miRNAs in animals.At the same time,some specificmiRNAs can be expressed. The expression of miRNA is different in and out of the tissure,miRNA is selectively released from cells in the peripheral. The selective mechnism and thestability help miRNA become as biomarkers of disease diagnosis. In the year of2008,Lawrie firstly detected miRNA-21in the serum of large B cell lymphoma patients [1]. Limade the miRNA as biomarkers of the infection of HBV,and hepatocellular carcinoma(HCC) that HBV was positive. In their study,they found that miRNA-375and miRNA-92ais unique to HBV infection, miRNA-375and miRNA-let-7f can be used as the biomarkersof diagnosis to HCC patients that HBV was positive, and the specificity of miRNA-375was96%, the sensitivity was100%[2]. Chen [3] found that there are17dysregulatedmiRNA in PBMC between sever hepatitis and HBV carriers,5overexpressed,such asmiRNA-1246,12down-regulated,such as miRNA-223,miRNA-547-3P,miRNA-150,and2was related with immune regulation,10was associated with the development of tumor,5was not refered in reports. Of12down-regulated expression miRNA,miRNA-150and miRNA-223may be associated with the activity of viral hepatitis, and miRNA-150mainlyinvolved in the regulation of B lymphocytes mature, adusting the differention of Th1andTh2cells in the body inflammation[4]．Objective To find altered expression profiles of microRNAs in PBMC ofacute-on-chronic liver failure patients caused by hepatitis B,and find some microRNAsinteracting with molecules associated with acute-on-chronic liver failure (hfgl2, Fas/FasL,TNF/TNFR1, IFN γ, CXCL10, TLR4),thus providing a new way for the diseasediagnosis,treatment,prevention.Methods Respectively collecting PBMC in peripheral blood of20patients in ofacute-on-chronic liver failure patients caused by hepatitis B and mild-chronic hepatitis B.Inthe present study,we firstly used the miRNA microarray of Gene Copoiea company to seekfor miRNAs with differential expression of the two groups,espescially changing more than2times (up-regulated or down-regulated).At the same time, with the aid of manybioinformatics target prediction software (for example,TargetScan and PicTar,MicroCosm)to find the miRNAs interaction with molecules associated with liver failure. In order toverify the reliability of the result, we adopt the GeneCopoeia company All-in-one miRNAqRT-PCR Detection Kit in expanding clinical specimens,U48is stably expressed in variouecells,as internal control used in the experiment. We calculated the data with2ΔΔCTmethod and analyzed the result with stastition.Results By the microarray and bioinformatics target prediction software, we found16kinds of miRNA were down-regulated in the PBMC of acute-on-chronic liver failurepatients,and miRNA-181c, miRNA-30e, miRNA-107, and miRNA-1826areassociated with molecules (hfgl2, Fas/FasL,TNF/TNFR1, INF γ, CXCL10,TLR4)up-regulated with liver failure.In expanding clinical specimens,we found thatmiRNA-181c was down-regulated in the PBMC of acute-on-chronic liver failure patients. Conclusion Compared with patients of mild-chronic hepatitis B, Has-miRNA-181cin PBMC of acute-on-chronic liver failure patients obviously expressed (significantlylowered).And Has-miRNA-181c may regulate the expression of INF γ,TNF, FasL,andmay play an important role in the disease of acute-on-chronic liver failure.To explorethe mechanism of hepatitis B infection, as well as to provide a new way forprevention and treatment of the disease of acute-on-chronic liver failure caused byHBV.