Proteomic profiling identifies key differences between inter-stage infants with single ventricle heart disease and healthy controls

Abstract

Despite significant morbidity among infants with single ventricle heart disease (SVHD), clinical monitoring is limited by poor understanding of the underlying pathobiology. Proteomics can identify novel biomarkers and important pathways in complex disease. No prior study has evaluated whether the proteome of SVHD infants differs from healthy controls, how it shifts after stage 2 palliation, or whether differences can predict post-operative outcomes. We present a prospective cohort study of cardiovascular proteomic phenotyping in infants with SVHD undergoing stage 2 palliation. Twenty-nine pre-stage-2 SVHD infants and 25 healthy controls were enrolled. Outcomes included postoperative hypoxemia and endotracheal intubation time. Serum samples were drawn pre-operatively (systemic and pulmonary vein) and at 24 hours postoperation. Targeted cardiovascular proteomic analysis included 184 proteins. Partial least squares discriminant analysis distinguished cases from controls (Accuracy = 0.98, R2 = 0.93, Q2 = 0.81) with decreased inflammatory mediators and increased modulators of vascular tone. Partial least squares discriminant analysis also distinguished cases pre-operation vs. post-operation (Accuracy=0.98, R2=0.99, Q2 = 0.92) with postoperative increase in both inflammatory and vascular tone mediators. Pre-operation pulmonary vein tissue inhibitor of metalloproteinase-1 (1.8x-fold, p=1.6 × 10-4) and nidogen-1 (1.5x-fold, p=1.7 × 10-4) were higher in subjects with longer endotracheal intubation time. Postoperation matrix metalloproteinase 7 levels were higher in subjects with greater postoperative hypoxemia (1.5x-fold, P= 1.97 × 10-5). Proteomic analysis identifies significant changes among SVHD infants pre- and post-stage 2, and healthy controls. Tissue inhibitor of metalloproteinase-1, nidogen-1, and matrix metalloproteinase 7 levels are higher in SVHD cases with greater morbidity suggesting an important role for regulation of extracellular matrix production. Proteomic profiling may identify high-risk SVHD infants.

Trial registration: ClinicalTrials.gov NCT03404258.

Conflict of interest statement

Disclosures: All authors have read the policy on disclosure of potential conflicts of interest and state that they have no conflicts of interest to disclose. All authors have read and are in agreement with the journal’s authorship agreement.

Copyright © 2020 Elsevier Inc. All rights reserved.

Figures

Figure 1:

Comparison of the Proteomic Signature between Inter-Stage SVHD Cases (1) and Controls (0). A) Partial least squares-discriminant analysis demonstrates a significant global shift in the proteome between controls (red circles) and SVHD cases pre-operatively (green circles). Accuracy=0.98, R2=0.93, Q2=0.81. B) Variable importance projection scores for the 15 most important proteins to distinguish the proteome of SVHD cases and controls. FGF=fibroblast growth factor, AGRP=Agouti-related protein, SELL=L-selectin, ADM=adrenomedullin, ICAM=intercellular adhesion molecule, PSGL=P-selectin glycoprotein ligand, APOM=apolipoprotein M, THPO=thrombopoietin, ACE=angiotensin converting enzyme, IL=interleukin, IL1 RL2=IL1 receptor ligand 2, GIF=gastric intrinsic factor, TF=tissue factor, CR=complement receptor.

Figure 2:

Comparison of the Proteomic Signature between SVHD Cases before Stage 2 (1) and 24-hour Post-Stage 2 (2). A) Partial least squares-discriminant analysis demonstrates a significant global shift in the proteome between pre-op (red circles) and 24h post-op (green circles). Accuracy=0.98, R2=0.99, Q2=0.92. B) Variable importance projection scores for the 15 most important proteins to distinguish the proteome of SVHD cases and controls. CNDP=B-Ala-His dipeptidase, IL=interleukin, PTX=pentraxin-related protein, LPL=lipoprotein lipase, SERPIN=plasma serine protease inhibitor, OSMR=oncostatin-M-specific-receptor, TIMP=tissue inhibitor of metalloproteinases, HO=heme oxygenase, SOD=superoxide dismutase, VEGFD=vascular endothelial growth factor D, GDF=growth/differentiation factor, F7=factor VII, TNFR SF=tumor necrosis factor receptor superfamily.

Figure 3:

Comparison of the post-operative proteomic signature between SVHD Cases with better (0) and worse (1) clinical outcomes. A) Partial least squares-discriminant analysis (PLS-DA) demonstrates a distinct pre-operative pulmonary vein (PV) proteome between those with shorter (red circles) and longer (green circles) post-operative intubation time. Accuracy=0.79, R2=0.99, Q2=0.49. B) Variable importance projection scores for the 10 proteins with greatest impact distinguishing between the pre-operative PV proteome of those with shorter v. longer post-op intubation duration. C) PLS-DA demonstrates a distinct post-operative proteome between those with lesser (red circles) and greater (green circles) hypoxemia burden in the first 24 hours after surgery. Accuracy=0.80, R2=0.99, Q2=0.35. B) Variable importance projection scores for the 10 proteins with greatest impact distinguishing between the post-operative proteome of those with lesser v. greater hypoxemia burden. TIMP1=tissue inhibitor of metalloproteinases, NID=nidogen, TIMD=t-cell immunoglobulin and mucin domain protein, CA=carbonic anhydrase, COL=collagen, ITGB1BP2=integrin beta1 binding protein 2, C2=complement 2, GP1BA=Platelet glycoprotein 1b alpha, CTSL=cathepsin, BNP=b-type natriuretic peptide, MMP=matrix metalloproteinase, PLA2G7=platelet activating factor acetyl hydrolase, PRSS8=prostasin, SCF=stem cell factor, THPO=thrombopoietin, FGF=fibroblast growth factor, PRSS2=trypsin 2, DECR1=2,4dienoyl-CoA reductase, SAA=serum amyloid A.