Search results for "synovia"
showing 10 items of 116 documents
Oxidative stress in osteoarticular diseases
2016
Effects of dexamethasone on human synovial fibroblast-like cells, from osteoarthritic joints, in culture.
1990
The effect of Dexamethasone (DEX) on cell division and macromolecular synthesis was investigated in a line (McCoy cells, A 9) of synovial fibroblast-like cells derived from human osteoarthritic joints. DEX markedly reduced the proliferation of McCoy cells in a time and dose-dependent manner. The maximal inhibition (45%) was found at 500 nM DEX 24 h after incubation and was accompanied by the appearance of giant macrophage-like cells. After DEX treatment cells showed increased content of DNA, proteins and RNA together with the reduction of [3H]-thymidine incorporation into the TCA-precipitable fraction.
Synovial giant cells in rheumatoid arthritis: Expression of cystatin C, but not of cathepsin B
2000
This study was designed to investigate the expression of the matrix degrading proteinase cathepsin B and its endogenous inhibitor cystatin C in rheumatoid arthritis (RA) with special regard to multinucleated synovial giant cells (SGC). We applied an immunohistochemical double-labeling technique. SGC strongly expressed cystatin C and CD68, but were negative for cathepsin B. This staining pattern occurred in osteoclasts as well. Our findings support the idea that in RA matrix destruction by cathepsin B is not mediated by SGC or osteoclasts, but by mononuclear synoviocytes.
Mechanobiological computational model for the development and formation of synovial joints
2019
El desarrollo de las articulaciones sinoviales se debe a diferentes factores genéticos, bioquímicos y mecánicos. Comienza en el brote de las extremidades, que tienen una masa ininterrumpida de células mesenquimales dentro de su núcleo, el blastema esquelético. La mayoría de estas células blastemales se diferencian en condrocitos; sin embargo, algunas de estas células permanecen, sin diferenciar, en el sitio de la futura articulación (interzona). La separación de los rudimentos ocurre con el proceso de cavitación dentro de la interzona. Después de la cavitación, se produce la morfogénesis articular y el hueso toma su forma final. Una vez finalizado el período embrionario, la articulación sin…
Human Memory Th17 Cell Populations Change Into Anti-inflammatory Cells With Regulatory Capacity Upon Exposure to Active Vitamin D
2019
Autoimmune diseases are characterized by an aberrantly activated immune system, resulting in tissue damage and functional disability in patients. An important therapeutic goal is to restore the deregulated immunological balance between pro- A nd anti-inflammatory T cells. This imbalance is illustrated by elevated levels and activity of memory Th17 cell populations, such as Th17, Th1/Th17, and Th17.1 cells, in various autoimmune diseases. These cells are characterized by the chemokine receptor CCR6, RORC expression and production of IL-17A, IFNγ, and TNFα. Using rheumatoid arthritis (RA) as a model of autoimmune disease, we here demonstrate that pro-inflammatory memory CCR6+ Th cells can swi…
Artificial cartilage bio-matrix formed of hyaluronic acid and Mg2+-polyphosphate.
2016
Here we show that inorganic polyphosphate (polyP), a polyanionic metabolic regulator consisting of multiple phosphate residues linked by energy-rich phosphoanhydride bonds, is present in the synovial fluid. In a biomimetic approach, to enhance cartilage synthesis and regeneration, we prepared amorphous polyP microparticles with Mg2+ as counterions. The particles were characterised by X-ray diffraction (XRD), energy-dispersive X-ray (EDX) and Fourier transformed infrared spectroscopic (FTIR) analyses. Similar particles were obtained after addition of Mg2+ ions to a solution containing hyaluronic acid, as a major component of the synovial fluid, and soluble Na-polyP. The viscous paste-like ma…
Cartilage Regeneration and Tissue Engineering
2019
Abstract Articular cartilage in synovial joints is a hyaline cartilage highly hydrated with a rigorous order of cells and fibers and a specific content of proteoglycans and glycoproteins. It provides a low-friction surface, participates in the lubrication of the synovial joints, and distributes the forces to the underlying bone. It is an avascular and aneural tissue where small metabolites diffuse to and from cells. Unlike hyaline cartilage in other locations, articular cartilage lacks perichondrium, a layer of fibrous tissue around it that serves as the source of new cartilage cells. Thus, although extracellular matrix undergoes continuous remodeling throughout life, the ability to repair …
C1q-bearing immune complexes detected by a monoclonal antibody to human C1q in rheumatoid arthritis sera and synovial fluids
1991
Using a monoclonal antibody directed against the C-chain of human C1q, we detected C1q-bearing immune complexes (IC) in sera and synovial fluids of rheumatoid arthritis (RA) patients. In a sandwich-ELISA, C1q-bearing IC were captured by the solid-phase monoclonal antibody and then detected with peroxidase-labeled F(ab')2-antibodies to either human IgG or IgM. The results of this assay were compared to an ELISA-modification of the C1q-solid-phase binding assay (C1q-SPBA). C1q-bearing IC were detected in 81.1% of RA-sera and the 65.2% of RA-synovial fluids. IgG as well as IgM was present in 72.6% of the sera and 70% of the synovial fluids which were positive in both assays. Most RA sera that …
Blocking Jak/STAT signalling using tofacitinib inhibits angiogenesis in experimental arthritis
2021
Abstract Objective During rheumatoid arthritis (RA), the angiogenic processes, occurring with pannus-formation, may be a therapeutic target. JAK/STAT-pathway may play a role and the aim of this work was to investigate the inhibiting role of a JAK-inhibitor, tofacitinib, on the angiogenic mechanisms occurring during RA. Methods After ethical approval, JAK-1, JAK-3, STAT-1, STAT-3 and VEGF expression was evaluated on RA-synovial-tissues. In vitro, endothelial cells (ECs), stimulated with 20 ng/ml of VEGF and/or 1 μM of tofacitinib, were assessed for tube formation, migration and proliferation, by Matrigel, Boyden chamber assay and ki67 gene-expression. In vivo, 32 mice received collagen (coll…