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Struglics, A.

Publications and source records attributed to Struglics, A..

3 recordsLinked to original sources

Inflammation-profiling reveals activated pathways and biomarkers with predictive potential in oligoarticular JIA

ObjectiveWe set out to profile the immune mechanisms active in treatment-naive oligoarticular JIA (oJIA) to improve understanding of its immunopathogenesis, to identify potential biomarkers that can aid diagnosis, predictions and correlate with clinical disease parameters. MethodsUsing Olink proteomics (Inflammation Panel), we defined and compared the inflammation profiles of 38 plasma and 62 synovial fluid (SF) oJIA samples, 38 plasma samples from healthy age- and sex-matched controls (HC), 12 SF samples from non-arthritic controls and 26 SF samples from knee injury patients. Clinical data were retrieved from the Swedish Pediatric Rheumatology Quality Register. ResultsPlasma profiles of oJIA and HC were largely overlapping, with IL6 and MMP-1 upregulated in oJIA. In SF, 48 differentially expressed proteins (DEPs) were identified in oJIA, highlighting immune pathways like leukocyte migration, cell chemotaxis and adaptive immunity. Comparative analysis revealed 13 proteins specific to oJIA. Correlations were found between DEPs in oJIA SF and clinical parameters (cJADAS-71, pain, health impact score). Plasma IL6 and MMP-1 showed strong correlation with disease activity and pain, respectively. CXCL9, CXCL10 and CXCL11 were identified as potential predictive biomarkers for disease progression. ConclusionsThe overlap in plasma inflammation profiles of oJIA and HCs suggests local rather than systemic inflammation in oJIA, underlining the need for synovial fluid-based immunopathogenesis studies. Adaptive immune signatures in oJIA SF distinguished it from knee injury patients, offering potential for diagnostic application. Increased CXCL9, CXCL10 and CXCL11 in SF were associated with chronic disease progression and could serve as prognostic biomarkers and early treatment targets.

immunology↗

The level of synovial human VEGFA, IL-8 and MIP-1α correlate with truncation of lubricin glycans in osteoarthritis

Osteoarthrithis (OA) is an endemic disease due to the increase of the worlds elderly population. Previously thought to be a consequence of an imbalance between cartilage degradation and biosynthesis, it is now recognized as a disease also involving inflammation, hence influencing the level of inflammatory cytokines, growth factors and chemokines. Lubricin is a mucin type molecule where its OA induced glycosylation truncation propels a deteriorating lubrication of the articular cartilage. The objective of this study was to explore the OA driven truncation of O-linked glycosylation of synovial lubricin and its cross talk with systemic and local (synovial fluid, SF) inflammation. We compared the systemic level of cytokines/chemokine in OA patients and controls plasma with their local level in SF using a 44 plex screen. The level of 27 cytokines and chemokines was consistently measured in both plasma and SF. The data showed that the levels of cytokines and chemokines in OA plasma display limited correlation to their counterpart in SF. The level of synovial IL-8 and MIP-1 and VEGFA in OA patients, but not their plasma level, where the only cytokines that displayed a significant correlation to the observed lubricin O-linked glycosylation truncation. These cytokines were also shown to be upregulated exposing fibroblast like synoviocytes from healthy and OA patients to recombinant lubricin with truncated glycans mainly consisting of Tn-antigens, while lubricin with sialylated and non-sialylated T anigens did not have any effect. The data suggest that truncated glycans of lubricin, as found in OA, promotes the synovial cytokine production and exerebate the local synovial inflammation.

pathology↗

Cathepsin G Degrades Synovial Fluid Lubricin: Relevance For Osteoarthritis Pathogenesis

Lubricin (PRG4) is a mucin type protein that plays an important role in maintaining normal joint function by providing lubrication and chondroprotection. Improper lubricin modification and degradation has been observed in idiopathic osteoarthritis (OA), while the detailed mechanism still remains unknown. We hypothesized that the protease cathepsin G (CG) may participate in degrading lubricin in synovial fluid (SF). The presence of endogenous CG in SF was confirmed in 16 patients with knee OA. Recombinant human lubricin (rhPRG4) and native lubricin purified from the SF of patients were incubated with exogenous CG and lubricin degradation was monitored using western blot, staining by Coomassie or Periodic Acid-Schiff in gels, and with proteomics. Full length lubricin ([~]300 kDa), was efficiently digested with CG generating a 25-kDa protein fragment, originating from the densely glycosylated mucin domain ([~]250 kDa). The 25-kDa fragment was present in the SF from OA patients, and the amount was increased after incubation with CG. A CG digest of rhPRG4 revealed 135 peptides and 72 glycopeptides, and confirmed that the protease could cleave in different domains of lubricin. Our results suggest that synovial CG may take part in the degradation of lubricin, which could affect the lubrication of OA joints.

pathology↗