Detection And Evaluation Of Serum Peptide Profiling In Liver Failure Patients

ObjectiveTo detect the serum peptide profiling in HBV-related chronic hepatitis and liver failure patients by using liquid chip time-of-flight spectrometry technology and preliminarily screen the liver failure-related candidate serum markers to provide experimental data and rationale for remedy clinical liver failure patients.MethodsMatrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) coupled with Weak-anion Exchange Chip(WCX) was used to detect the serum peptide profiling of 51 patients with liver failure(establishing pattern group) and 25 chronic hepatitis(establishing pattern group).We searched the differently expressed peptide peaks by FlexAnalysis 3.0 and ClinProTools 2.1 software,set up diagnostic pattern between liver failure and hepatitis and evaluated its accuracy and recognition rate by screening another 25 liver failure and 8 hepatitis patients(blind screening group) in blind.Meanwhile,we searched the differently expressed peptide peaks between acute-on-chronic liver failure patients and chronic liver failure patients,set up their diagnostic pattern and further evaluated it in blind test for reliability.Results87 peptide peaks were detected at the m/z values of 800 to 10000 in the establishing pattern group(51 liver failure and 25 hepatitis) and 61 peptide peaks were significantly different(P < 0.01) by FlexAnalysis 3.0 and ClinProTools 2.1 software. A diagnostic pattern consisting of 5 peptide peaks was established based on the Genetic Algorithm classifiers.The m/z was 1944.43,4942.04,4963.59,7765.36, 9289.21respectively.Among them,two peptide peaks with 4942.04,4963.59 were up-regulated,and the other peptide peaks were down-regulated in liver failure patients.The discriminatory pattern could recognize 24 from 25 cases of liver failure (the accuracy was 96%) and 8 cases of hepatitis controls were all recognized(the accuracy was 100%) in the blind test for validation.The diagnostic pattern could discriminate liver failure from hepatitis well and the predictive model derived from these discriminating peaks had highly recognition rate(97.41%).Comparing the serum peptide profiling of acute-on-chronic liver failure with that of chronic liver failure,three peptide peaks with 3140.91,2560.5,2739.59 at m/z 800-10000Da were detected in the acute-on-chronic liver failure which were up-regulated.While the peptide peak of 2941.96 was low-regulated(P<0.05).A diagnostic pattern consisting of 5 peptide peaks was established between acute-on-chronic liver failure and chronic liver failure by Genetic Algorithm classifiers.The m/z was 9288.97,2925.57, 4679.56,1518.39,2899.12respectively.Additional sera including 13 acute-on-chronic liver failure patients and 12 chronic liver failure patients were used in the blind test for validation.The research showed that the diagnostic pattern could recognize 10 from 13 cases of acute-on-chronic liver failure(with accuracy of 77%) and 9 from 12 cases of chronic liver failure(with accuracy of 75%).The recognition rate of this diagnostic pattern showed 88.15%.ConclusionUsing liquid chip time-of-flight spectrometry technology,we have discovered a candidate pattern consisting of 5 peaks that can distinguish serum samples from hepatitis controls and liver failure patients.ClinProt magnetic beads in combination with MALDI-TOF Mass Spectrometry are effective tools to investigate potential diagnostic biomarker for liver failure.However,further comparative proteomic analysis and model validation research need to be acquired from a larger number of patients.