Serological profiling of Crohn’s disease and ulcerative colitis patients reveals anti-microbial antibody signatures

BACKGROUND The healthcare burden of inflammatory bowel disease(IBD)is rising globally and there are limited non-invasive biomarkers for accurate and early diagnosis.AIM To understand the important role that intestinal microbiota play in IBD pathogenesis and identify anti-microbial antibody signatures that benefit clinical management of IBD patients.METHODS We performed serological profiling of 100 Crohn’s disease(CD)patients,100 ulcerative colitis(UC)patients and 100 healthy controls against 1173 bacterial and 397 viral proteins from 50 bacteria and 33 viruses on protein microarrays.The study subjects were randomly divided into discovery(n=150)and validation(n=150)sets.Statistical analysis was performed using R packages.RESULTS Anti-bacterial antibody responses showed greater differential prevalence among the three subject groups than anti-viral antibody responses.We identified novel antibodies against the antigens of Bacteroidetes vulgatus(BVU_0562)and Streptococcus pneumoniae(SP_1992)showing higher prevalence in CD patients relative to healthy controls.We also identified antibodies against the antigen of Streptococcus pyogenes(SPy_2009)showing higher prevalence in healthy controls relative to UC patients.Using these novel antibodies,we built biomarker panels with area under the curve(AUC)of 0.81,0.87,and 0.82 distinguishing CD vs control,UC vs control,and CD vs UC,respectively.Subgroup analysis revealed that penetrating CD behavior,colonic CD location,CD patients with a history of surgery,and extensive UC exhibited highest antibody prevalence among all patients.We demonstrated that autoantibodies and anti-microbial antibodies in CD patients had minimal correlation.CONCLUSION We have identified antibody signatures for CD and UC using a comprehensive analysis of antimicrobial antibody response in IBD.These antibodies and the source microorganisms of their target antigens improve our understanding of the role of specific microorganisms in IBD pathogenesis and,after future validation,should aid early and accurate diagnosis of IBD.

Nanotrap-enabled quantification of KRAS-induced peptide hydroxylation in blood for cancer early detection

Circulating peptide is a potential source of biomarkers for cancer detection.However,the existence of large molecular weight proteins in plasma have a disastrous effect on circulating peptides isolating and detecting.Herein,nanotrap fractionation following by mass spectrometry have been applied to quantify the levels of bradykinin (BK) and hydroxylated bradykinin (Hyp-BK) as a relative measure of KRAS-regulated prolyl-4-hydroxylase alpha-1 (P4HA1) which may serve as early diagnosis marker for pancreatic ductal adenocarcinoma (PDAC).We found that P4HA1 can be upregulated by KRASG12v,which is a PDAC driver mutation,using HPNE/KRAS and HPNE cells.And we revealed that P4HA1 is overexpressed in PDAC tumors,compared to normal and inflamed pancreatic tissues.RNA interference revealed that P4HA1 activity was primarily responsible for Hyp-BK production.Mass spectrometry analysis revealed that plasma Hyp-BK/BK ratio was higher in PDAC than pancreatitis patients and healthy controls,while the area under the receiver operating characteristic (ROC) curve (AUC) is 0.8209 (95%Cl,0.7269-0.9149).The Hyp-BK/BK association with PDAC was reproduced in another cohort,where this ratio was found to increase with advancing tumor stage.These novel findings paved the way for wider applications of Nanotrap coupled mass spectrometry as a powerful tool for revealing biosignatures from plasma.