Article Text

PDF
Extended report
From gene expression to serum proteins: biomarker discovery in ankylosing spondylitis
  1. N Haroon1,2,
  2. F W L Tsui1,2,
  3. F D O’Shea1,2,
  4. B Chiu1,
  5. H W Tsui1,
  6. H Zhang3,
  7. K W Marshall1,2,3,
  8. R D Inman1,2
  1. 1
    Toronto Western Research Institute, Ontario, Canada
  2. 2
    University of Toronto, Toronto, Ontario, Canada
  3. 3
    GeneNews Limited, Richmond Hill, Ontario, Canada
  1. Correspondence to Dr R D Inman, Arthritis Center of Excellence, Toronto Western Hospital, 399 Bathurst St, Toronto, ON M5T 2S8, Canada; robert.inman{at}uhn.on.ca

Abstract

Objectives: Studying post-infliximab gene expression changes could provide insights into the pathogenesis of ankylosing spondylitis (AS).

Methods: Gene expression changes were screened by microarray on peripheral blood RNA of 16 AS patients at baseline and 2 weeks post-infliximab, and selected results were confirmed by quantitative real-time (qRT)–PCR. Corresponding serum-soluble LIGHT (sLIGHT) was estimated by ELISA and the fold change in sLIGHT was correlated to the fold change in erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and the Bath AS disease activity index.

Results: Post-infliximab, 69% of the patients (11/16) achieved an ASAS20 response. Six candidate genes were differentially expressed by microarray; four of which were validated by qRT–PCR. sLIGHT showed the most significant difference. There was good correlation of baseline sLIGHT with CRP (R  =  0.60; p = 0.01) and ESR (R  =  0.51; p = 0.04). The fold change in sLIGHT correlated with change in both CRP (R  =  0.71, p = 0.002) and ESR (R  =  0.77, p<0.001).

Conclusion: LIGHT is significantly downregulated by infliximab. sLIGHT correlated well with changes in inflammatory markers.

Statistics from Altmetric.com

Footnotes

  • Competing interests None.

  • Ethics approval The study was approved by the University Health Network ethics board.

  • Patient consent Obtained.

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.