Interleukin (IL)-36 is a family of cytokines that belongs to the larger IL-1 superfamily. IL-36 agonist/antagonist binds to the interleukin-36 receptor involving in physiological inflammation regulation and pathogenesis of many inflammatory diseases. In inflammatory joint diseases, the expression of IL-36 changes, and some studies have initially explored the role of IL-36 in these diseases. In psoriatic arthritis, IL-36 signal mediates plasma cell and fibroblast-like synoviocyte crosstalk presenting IL-36 agonist/antagonist imbalance. In rheumatoid arthritis, IL-36 agonists induce fibroblast-like synoviocyte to produce pro-inflammatory factors, while IL-36 antagonist deficiency leads to lesion progression. In osteoarthritis, IL-36 agonists induce chondrocytes to produce catabolic enzymes and pro-inflammatory factors. This article reviews the expression and function of IL-36 in different inflammatory joint diseases to provide a reference for revealing their pathogenic mechanisms and discovering therapeutic targets.
Humans ; Interleukins ; Arthritis, Rheumatoid ; Osteoarthritis/pathology* ; Arthritis, Psoriatic/metabolism* ; Cytokines

No abstract available.
Arthritis, Rheumatoid* ; Folic Acid* ; Metabolism* ; Methotrexate*

Fractionation of protein components of the human synovial fluid was carried out with paper and disc electrophoresis, and isoelectric focusing. The mean ranges of total protein content of synovial fluid obtained in the thirty patients suffering from nonspecific and traumatic synovitis, degenerative osteoarthritis or rheumatoid arthritis were 3.8 to 4.6g/dl. There was no significant difference between each from of arthritis. The pattern of protein fractionation of synovial fluid by paper electrophoresis was similar to that of serum protein. On disc electrophoresis, 20 fractions were identified in synovial fluid and the main fraction was albumin. Isoelectric focusing of the human serum with Ampholine carrier ampholyte in thin layer polyacrylamide gel revealed 27 protein fractions and five isoenzymes of amylase and two of them were the main fractions. In the synovial fluid 22 protein fractions and two isoenzymes of amylase, which had the same isoelectric points as the main fractions of serum, were noted. It is suggested that the isoamylases in the synovial fluid are a dialysate of plasma enzymes.
Arthritis, Rheumatoid/metabolism ; Human ; Osteoarthritis/metabolism ; Proteins/metabolism* ; Synovial Fluid/metabolism* ; Synovitis/metabolism

IL-32 acts as a pro-inflammatory cytokine by inducing the synthesis of inflammatory molecules as well as promoting the morphological changes involved in the transformation of monocytes into osteoclasts (OCs). Evaluation of the functions of IL-32 has mainly focused on its inflammatory properties, such as involvement in the pathogenesis of various autoimmune diseases. Recently, IL-32 was shown to be involved in bone metabolism, in which it promotes the differentiation and activation of OCs and plays a key role in bone resorption in inflammatory conditions. IL-32γ also regulates bone formation in conditions such as ankylosing spondylitis and osteoporosis. In this review, we summarize the results of recent studies on the role of IL-32γ in bone metabolism in inflammatory arthritis.
Arthritis* ; Arthritis, Rheumatoid ; Autoimmune Diseases ; Bone Resorption ; Inflammation ; Metabolism* ; Monocytes ; Osteoblasts ; Osteoclasts ; Osteogenesis ; Osteoporosis ; Spondylitis, Ankylosing

OBJECTIVES: Mutation of p53 may play a role in manifestation of rheumatoid arthritis synovium, but several studies on p53 expression in synovial tissues of rheumatoid arthritis showed conflicting results. We investigated the amount and pattern of p53 positive cells in rheumatoid arthritis synovium, in comparison with osteoarthritis synovium, by using immunohistochemistry with two other monoclonal antibodies for p53. METHODS: Synovial tissues from 9 patients with rheumatoid arthritis and 5 patients with osteoarthritis were examined for p53 expression by immunohistochemistry with 2 monoclonal antibodies for p53, DO-1 and DO-7. Histologic features of inflammation were also scored and compared with p53 expression. RESULTS: There was no significant difference between inflammatory scores in both groups. In the synovial tissues of rheumatoid arthritis patients, p53 positive cells were detected in 3 out of 9 samples(33%) and p53 expressions were restricted to inflammatory mononuclear cells, but synovial lining cells, subsynovial fibroblast-like cells and vascular endothelial cells were p53 negative. p53 expressions in osteoarthritis synovial tissues as control were observed in 2 out of 5 samples(40%) and the amount and pattern of p53 positive cells were comparable to those seen in rheumatoid arthritis synovial tissues. There was no demonstrable correlation between the synovial tissues of both groups with respect to inflammation scores and expression of p53 protein. CONCLUSION: Our findings suggest that altered p53 expression may not play a significant role in the manifestation of rheumatoid arthritis synovium. However these data need to be strengthened by increasing the number of samples and molecular biology approaches.
Arthritis, Rheumatoid/metabolism* ; Arthritis, Rheumatoid/genetics ; Comparative Study ; Gene Expression ; Genes, p53 ; Human ; Immunohistochemistry ; Osteoarthritis/metabolism ; Osteoarthritis/genetics ; Protein p53/metabolism* ; Protein p53/genetics ; Synovial Membrane/metabolism

OBJECTIVETo show the involvement of lymphocyte-derived catecholamines in the pathogenesis of rheumatoid arthritis (RA), we investigated the change in expression of tyrosine hydroxylase (TH), a rate-limiting enzyme of catecholamine synthesis, by CD4+ T lymphocytes in lymphoid tissues of DBA/1 mice with collagen-induced arthritis (CIA).

METHODSCIA model was induced by chicken type II collagen in DBA/1 mice. The joints of the mice were observed for clinical score of swelling on and after the 22nd day of primary immunization. Pathological changes of ankles were examined by staining of tissue sections with hematoxylin and eosin on the 35th and 55th day following primary immunization. Immunofluorescent histochemistry was used to identify the number of TH-positive, CD4-positive, and double-labeled cells in the mesenteric lymph nodes and the spleen.

RESULTSPaw-swelling onset was on days 29 - 32 after the first immunization in DBA/1 mice. Clinical score for swelling of the paws reached peak on day 46 after the first immunization. Compared with the ankles of intact or vehicle mice, the joints of CIA mice had these characteristics: increased inflammatory cells in the synovial tissues, proliferated synoviocytes in the multilayers, narrowed articular space, and destructed articular cartilages. Simultaneously, the number of TH-positive, CD4-positive, and double-labeled cells in the mesenteric lymph nodes and the spleen was significantly increased on days 35 and 55 following the first immunization. Between day 35 and day 55 post-immunization, there was no significant difference in the number of these positive cells.

CONCLUSIONCD4+ T lymphocytes up-regulate TH expression in the process of CIA and therefore, it is suggested that endogenous catecholamines of lymphocytes involve in the pathogenesis of RA.

Animals ; Arthritis, Experimental ; metabolism ; Arthritis, Rheumatoid ; CD4-Positive T-Lymphocytes ; metabolism ; Lymphoid Tissue ; metabolism ; Male ; Mice ; Mice, Inbred DBA ; Tyrosine 3-Monooxygenase ; metabolism

A 63-year old man developed acute monoarthritis in the dorsum of the left foot. Polarized light microscopy of the synovial fluid from his third metatarsophalangeal joint revealed numerous positively birefringent lipid spherules with a maltese cross appearance. Positively birefringent lipid spherules can be found in association with acute, otherwise unexplained arthritis, and may induce synovial inflammation similar to that seen in other types of crystal-induced arthritis. We report a case of acute monoarthritis in which large numbers of positively birefringent lipid spherules were present in a hyperlipidemic diabetic patient.
Acute Disease ; Arthritis/metabolism* ; Arthritis/complications* ; Birefringence ; Case Report ; Crystallization ; Diabetes Mellitus/blood* ; Human ; Hyperlipidemia/complications* ; Lipids/metabolism* ; Male ; Middle Age ; Synovial Fluid/metabolism*

AIMTo determine the exact roles of prolactin (PRL) in the pathogenesis of rheumatoid arthritis (RA) and supply experimental basis for clinical treatment of RA, and to investigate the expression of matrix metalloproteinase-9 (MMP-9) in the synovium of adjuvant arthritis rats.

METHODSForty rats were divided into four groups (n = 10): (1) Normal control group (group A); (2) Adjuvant arthritis control group (group B); (3) Hyperprolactinemic adjuvant arthritis group (group C); (4) Hypoprolactinemic adjuvant arthritis group (group D). The content of PRL in the serum was detected by radio-immunoassay method. The activity of MMP-9 was analyzed by gelatin zymography. The alteration of MMP-9 immunoreactivity were investigated by means of immunohistochemistry in the synovium of all groups. The expressions of MMP-9 were investigated by Western blot in the synovium of all groups.

RESULTSCompared with group A, the activity and expression of MMP-9 of group B in the synovium were highly increased. The activity and expression of MMP-9 in the synovium were the most distinctive in group C. Compared with group B, the activity and expression of MMP-9 in the synovium were decreased in group D, but still higher than group A.

CONCLUSIONThe present results indicated that PRL might involved in the pathogenesis of RA by regulating the secretion of MMP-9 in the synovium.

Animals ; Arthritis, Experimental ; metabolism ; Arthritis, Rheumatoid ; physiopathology ; Male ; Matrix Metalloproteinase 9 ; genetics ; metabolism ; Prolactin ; blood ; physiology ; Random Allocation ; Rats ; Rats, Wistar ; Synovial Membrane ; metabolism

OBJECTIVE: To detect receptor activator of nuclear factor kappa B ligand (RANKL) expressed on B10 cells in rheumatoid arthritis (RA) and to evaluate the correlation between RANKL-producing B10 cells in RA and clinical features and laboratory parameters, trying to reveal the possible role of B10 cells in the pathogenesis of RA and the potential mechanism of impaired immunosuppressive capacities. METHODS: 25 RA patients and 20 healthy volunteers were enrolled. These RA patients did not received treatment with glucocorticoids, disease-modifying anti-rheumatic drug and biologics during the recent half of a year. The levels of RANKL-producing B10 cells were measured by flow cytometry (FCM) and polymerase chain reaction (PCR). The correlation between the frequencies of RANKL-producing B10 cells in RA and clinical data, laboratory parameters were analyzed. The role of tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) in inducing RANKL expression in B10 cells was evaluated by in vitro stimulation assay. Independent samples t test, Pearson and Spearman correlation were used for statistical analysis. RESULTS: B10 cells were capable of producing RANKL at a low level in health controls. The frequencies of RANKL-producing B10 cells were markedly higher in RA patients than in health controls (3.65%±1.59% vs. 2.25%±0.68%, P<0.01). The frequencies of these cells correlated positively with RA tender joint counts, swollen joint counts and disease activity score in 28 joints (DAS28) (r=0.479, P=0.035; r=0.519, P=0.008; r=0.526, P=0.019). However, no correlation was found between these cells and RA patient age, disease duration, or the levels of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF) and anti-citrullinated peptide antibody (ACPA). After in vitro stimulation by TNF-α, but not IL-1β, B10 cells isolated from healthy donors demonstrated fundamentally upregulated expression of RANKL. CONCLUSION Our studies showed the frequencies of RANKL-producing B10 cells were markedly higher in RA patients, and their frequencies were positively correlated with RA tender joint counts, swollen joint counts and DAS28. These findings suggested that B10 cells might be involved in RA bone destruction.
Antirheumatic Agents ; Arthritis, Rheumatoid/metabolism* ; Autoantibodies/metabolism* ; B-Lymphocytes, Regulatory/metabolism* ; Humans ; RANK Ligand/metabolism* ; Rheumatoid Factor

A 30-year-old female patient with coexisting ankylosing spondylitis and rheumatoid arthritis was diagnosed and treated. The human leukocyte antigen (HLA)-B27 is a predisposing factor of ankylosing spondylitis and HLA-DR4 is a predisposing factor of rheumatoid arthritis. This patient was HLA-B27 and HLA-DR4 positive, and ankylosing spondylitis manifested before rheumatoid arthritis. After disease modifying anti-rheumatic drugs successfully arrested ankylosing spondylitis activity the patient conceived and delivered a healthy baby. One year later, she developed peripheral polyarthritis and was diagnosed with rheumatoid arthritis. We hypothesized that pregnancy may be one of the environmental factors that can activate rheumatoid arthritis, and that disease modifying anti-rheumatic drugs play an important role in keeping the disease under control.
Adult ; Arthritis, Rheumatoid ; diagnosis ; metabolism ; Female ; HLA-B27 Antigen ; metabolism ; HLA-DR4 Antigen ; metabolism ; Humans ; Spondylitis, Ankylosing ; diagnosis ; metabolism