THU0019 INHIBITION OF FUCOSYLATION IN ENDOTHELIAL CELLS REDUCES RHEUMATOID ARTHRITIS ANGIOGENESIS

Abstract

Background: Glycosylation has been reported to associate with tumor invasion and metastasis. Fucosylation is involved the biological functions of adhesion molecules and growth factor receptors. In regards to arthritis, we have previously reported that fucosylated proteins were expressed in rheumatoid arthritis (RA) synovial tissues. However, a direct role for fucosylated cytokines in RA has not been demonstrated. Objectives: To confirm that fucosylated proteins are expressed in RA and are involved in RA angiogenesis. Methods: Total glycans were determined in serum from normal (NL) subjects and RA patients using mass spectrometry. N-glycans from 10 RA or 10 healthy controls, and 10 pretreatment with tocilizumab (TCZ) or after treatment sera at 24 weeks were purified by glycoblotting using BlotGlycoH.To determine whether fcosylated proteins involved with RA inflammation, the correlation with disease activity score (DAS) 28 (ESR) was measured. 2-deoxy-D-galactose (2-dGal) is an analog of hexose that inhibits fucosylation. In order to confirm the role of fucosylation in RA angiogenesis, we did Matrigel assays in vitro. To block the expression of fcosylated proteins, human umbilical vein endothelial cells (HUVECs) were treated with 2-dGal (15 mM) for 5 days. After treatment with 2-dGal, HUVECs were plated on Matrigel and were incubated with phosphate buffered saline (PBS) or RA synovial fluids. In addition, chemotaxis assays were performed to determine the role of fucosylation in HUVEC migration. Finally, expression of proangiogenic cytokines such as fractalkine/CX3CL1, CXCL16, interleukin (IL)-8/CXCL8, monocyte chemotactic protein 1 (MCP-1)/CCL2, epithelial neutrophil-activating protein 78 (ENA-78)/CXCL5 and vascular endothelial growth factor (VEGF) in 2-dGal treated HUVEC conditioned medium were measured by ELISA. Results: Total glycans in RA serum were significantly higher than in NL serum [mean ± SEM; 477 ± 24 pmol/μl (n=10) and 339 ± 14 pmol/μl (n=10), p Conclusion: These data indicate that glycoproteins are involved with RA, and play a role in angiogenesis in RA and suggest that targeting glycosylation especially fucosylation may provide a method by which to decrease inflammation and potentially treat other inflammatory diseases. Disclosure of Interests: None declared