Inflammation

, Volume 37, Issue 5, pp 1459–1467

Identification of Potential Serum Biomarkers for Rheumatoid Arthritis by High-Resolution Quantitative Proteomic Analysis

Article

DOI: 10.1007/s10753-014-9871-8

Cite this article as:
Cheng, Y., Chen, Y., Sun, X. et al. Inflammation (2014) 37: 1459. doi:10.1007/s10753-014-9871-8

Abstract

The aim of this study was to find serum biomarkers of rheumatoid arthritis (RA) by high-resolution proteomic analysis. Low-abundance proteins from pooling serum sample of early RA patients and healthy controls were enriched using ProteoMiner™ enrichment kits. The enriched proteins were separated on SDS-PAGE, digested by trypsin, labeled with tandem mass tag (TMT) reagents, and desalted by C18 stage tip column. Then, the labeled peptides were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) with nano-LC combined with Orbitrap Q Exactive mass spectrometer, and experiments were carried out three times using different specimens, and differentially expressed proteins were screened by intensity ratios of identified peptides. Enzyme-linked immunosorbent assays (ELISAs) were performed to confirm differentially expressed proteins. Twenty-six proteins were found differentially expressed in RA serum by high-resolution proteomic analysis. Among them, levels of thrombospondin-1, ficolin-2, isoform 10 of fibronectin, and apolipoprotein E were higher in RA patients than in healthy controls (RA/healthy control (HC) ≥ 1.5, p < 0.05), while levels of angiotensinogen, paraoxonase/arylesterase 1, isoform E of proteoglycan 4, and plasminogen were significantly lower (RA/HC ≤ 0.67, p < 0.05). Further study by ELISA showed a higher level of ficolin-2 in the serum of RA patients compared to healthy controls; the level of ficolin-2 was found to be positively correlated with swollen joint counts (SJCs), disease activity score (DAS28), rheumatoid factor, and IgM in RA patients and with DAS28 and IgM in early RA patients through statistical analysis. The results of this study suggest that ficolin-2, as a newly screened biomarker by high-resolution quantitative proteomic analysis, offers the potentiality to become a diagnostic or disease evaluation tool in RA.

KEY WORDS

rheumatoid arthritis proteomic analysis orbitrap ficolin-2 

ABBREVIATIONS

RA

Rheumatoid arthritis

ELISA

Enzyme-linked immunosorbent assay

SJCs

Swollen joint counts

TJCs

Tender joint counts

DAS

Disease activity score

MALDI-TOF

Matrix-assisted laser desorption/ionization time of flight

TMT

Tandem mass tag

SSc

Systemic sclerosis

OA

Osteoarthritis

BD

Behcet’s disease

HC

Healthy control

CRP

C-reactive protein

ESR

Erythrocyte sedimentation rate

2-DE

Two-dimensional electrophoresis

TSP-1

Thrombospondin-1

FCN-2

Ficolin-2

Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Department of Rheumatology and Immunology, People’s HospitalPeking UniversityBeijingChina
  2. 2.Department of Rheumatology and ImmunologyBeijing HospitalBeijingChina
  3. 3.School of Life SciencesTsinghua UniversityBeijingChina