Subclinical gut inflammation in spondyloarthritis is associated with a pro-angiogenic intestinal mucosal phenotype

Background Vascular endothelial growth factor (VEGF-A) and placental growth factor (PlGF) are major regulators of pathological angiogenesis, which is a prominent feature of both Crohn's disease (CD) and peripheral synovitis in spondyloarthritis. Objective To investigate the presence of VEGF-A and PlGF in the gut of spondyloarthritis patients and to link this finding with subclinical gut inflammation in these patients. Methods Intestinal biopsies from healthy controls, CD patients, spondyloarthritis patients with or without subclinical gut inflammation and rheumatoid arthritis (RA) patients were stained for VEGF-A, PlGF, CD31 and vascular cell adhesion molecule 1 (VCAM-1) and digitally analysed. Results Spondyloarthritis patients with subclinical gut inflammation had markedly increased intestinal VEGF-A expression (p