Deep Coverage Tissue and Cellular Proteomics Revealed IL-1β Can Independently Induce the Secretion of TNF-Associated Proteins from Human Synoviocytes

Abstract

Synovitis is a key contributor to the inflammatory environment in osteoarthritis (OA) joints. Currently, the biological therapy of OA is not satisfactory in multiple single-target trials on anti-TNF agents, or IL-1 antagonists. Systems biological understanding of the phosphorylation state in OA synovium is warranted to direct further therapeutic strategies. Therefore, in this study, we compared the human synovial phosphoproteome of the OA with the acute joint fracture subjects. We found that OA synovium had significantly more phosphoproteins, and 82 phosphoproteins could only be specifically found in all the OA samples. Differentially expressed proteins of the OA synovium were focusing on endoplasmic reticulum-/Golgi-associated secretion and negative regulation of cell proliferation, which was verified through an IL-1β-treated human synoviocyte (HS) in vitro model. With data-independent acquisition-based mass spectrometry, we found that IL-1β could induce HS to secrete proteins that were significantly associated with the endosomal/vacuolar pathway, endoplasmic reticulum/Golgi secretion, complement activation, and collagen degradation. Especially, we found that while specifically suppressing HS endocytosis, IL-1β could activate the secretion of 25 TNF-associated proteins, and the change of SERPINE2 and COL3A1 secretion was verified by immunoblotting. In conclusion, our results suggest that OA synovium has a polarized phosphoproteome to inhibit proliferation and maintain active secretion of HS, whereas IL-1β alone can transform HS to produce a synovitis-associated secretome, containing numerous TNF-associated secretory proteins in a TNF-independent mode.

Quantitative Proteomic Analysis of Bi Zhong Xiao Decoction Against Collagen-induced Arthritis Rats in the Early and Late Stages

“…(30) Studies have con rmed that IL-1β could induce the upregulated secretion of COL3A1 from the human synoviocyte. (31) Our research demonstrated that BZXD could inhibit the expression of IL-1β and COL3A1 is decreased in the BZXD group relative to the CIA group. Thence, COL3A1 may be a molecular marker for BZXD treating RA.…”

COL3A1 and MMP9 Serve as Potential Diagnostic Biomarkers of Osteoarthritis and Are Associated With Immune Cell Infiltration

“…Evidence suggests that the expression levels of COL3A1 increased in the early stages of OA and decreased in the later stages (Rai et al, 2019). Tang et al (2018) also discovered that IL-1 increased the protein levels of COL3A1 in synoviocytes. MMP9, also known as gelatinase B, is an enzyme that degrades the ECM components such as collagen, fibronectin, and laminin.…”

Differential Secretome Profiling of Human Osteoarthritic Synoviocytes Treated with Biotechnological Unsulfated and Marine Sulfated Chondroitins

“…Secretome studies by high-resolution mass spectrometry on primary human synoviocytes, the main cellular components of the synovium, are lacking. Indeed, to date, a phosphoproteomic analysis of synoviocytes has only been reported by Tang and co-workers [37]. In addition, extensive proteomic characterizations have been performed so far on OA synovial fluids [38][39][40][41][42][43][44].…”