Rheumatoid arthritis: clinical features and pathogenetic mechanisms

An Unusual and Rare Location of Intra-articular Rheumatoid Nodule in the Elbow Joint - A Case Report

Rheumatoid nodules are the most common extra-articular manifestation of rheumatoid arthritis. Intra-articular rheumatoid nodules are very rare and usually associated with clinical symptoms. Case reports of intra-articular rheumatoid nodules in the knee joint, wrist joint, ankle joint, and sacrococcygeal joint are reported. However, an intra-articular rheumatoid nodule in the elbow joint has not been reported in the literature. Herein, we report a unique and rare case of a symptomatic intra-articular rheumatoid nodule in the elbow joint of a 49-year-old female with a 15-year history of rheumatoid arthritis. The symptoms resolved after surgical excision of the nodule.

The Role of Yersinia enterocolitica O:3 Lipopolysaccharide in Collagen-Induced Arthritis

Yersinia enterocolitica O:3 is mentioned among the most common arthritogenic pathogens. Bacterial components (including lipopolysaccharide (LPS)) may persist in the joint after eradication of infection. Having an adjuvant activity, LPS may enhance production of anticollagen antibodies, involved in the pathogenesis of rheumatoid arthritis. Furthermore, its ability to activate complement contributes to the inflammation. The aim of this work was to investigate whether Yersinia LPS (coinjected with collagen) is associated with arthritis progression or other pathological effects and to elucidate the mechanism of this association. It was demonstrated that murine mannose-binding lectin C (MBL-C) recognizes the inner core heptoses of the Rd1 chemotype LPS of Yersinia. In addition, the Rd1 LPS activates the MBL-associated serine protease 1 (MASP-1) stronger than the S and Ra chemotype LPS and comparable to Klebsiella pneumoniae O:3 LPS. However, in contrast to the latter, Yersinia Rd1 LPS was associated neither with the adjuvancity nor with the enhancement of pathological changes in animal paws/impairment of motility. On the other hand, it seemed to be more hepatotoxic when compared with the other tested endotoxins, while the enlargement of inguinal lymph nodes and drop in hepatic MBL-C expression (at the mRNA level) were independent of LPS chemotype. Our data did not suggest no greater impact Y. enterocolitica O:3 on the development or severity of arthropathy related to anticollagen antibody-induced arthritis in mice, although its interaction with MBL-C and subsequent complement activation may contribute to some adverse effects.

Increased Reactive Oxygen Species Formation and Oxidative Stress in Rheumatoid Arthritis

Background

Rheumatoid arthritis (RA) is an autoimmune inflammatory disorder. Highly reactive oxygen free radicals are believed to be involved in the pathogenesis of the disease. In this study, RA patients were sub-grouped depending upon the presence or absence of rheumatoid factor, disease activity score and disease duration. RA Patients (120) and healthy controls (53) were evaluated for the oxidant—antioxidant status by monitoring ROS production, biomarkers of lipid peroxidation, protein oxidation and DNA damage. The level of various enzymatic and non-enzymatic antioxidants was also monitored. Correlation analysis was also performed for analysing the association between ROS and various other parameters.

Methods

Intracellular ROS formation, lipid peroxidation (MDA level), protein oxidation (carbonyl level and thiol level) and DNA damage were detected in the blood of RA patients. Antioxidant status was evaluated by FRAP assay, DPPH reduction assay and enzymatic (SOD, catalase, GST, GR) and non-enzymatic (vitamin C and GSH) antioxidants.

Results

RA patients showed a higher ROS production, increased lipid peroxidation, protein oxidation and DNA damage. A significant decline in the ferric reducing ability, DPPH radical quenching ability and the levels of antioxidants has also been observed. Significant correlation has been found between ROS and various other parameters studied.

Conclusion

RA patients showed a marked increase in ROS formation, lipid peroxidation, protein oxidation, DNA damage and decrease in the activity of antioxidant defence system leading to oxidative stress which may contribute to tissue damage and hence to the chronicity of the disease.

SLC19A1 80G allele as a biomarker of methotrexate-related gastrointestinal toxicity in Portuguese rheumatoid arthritis patients

AIM

The aim of our study was to characterize the association of clinicopathological variables and the SLC19A1/RFC-1 G80A polymorphism in methotrexate (MTX)-related toxicity in Portuguese patients with rheumatoid arthritis.

PATIENTS & METHODS

The study included 233 consecutively recruited patients with rheumatoid arthritis under MTX treatment. The SLC19A1 G80A polymorphism was evaluated by PCR-RFLP.

RESULTS

Statistical analysis revealed that SLC19A1 80G carriers had increased risk of gastrointestinal toxicity (odds ratio [OR]: 2.61, p = 0.019) and that regular folic acid supplementation was associated with both overall and gastrointestinal toxicity protection (OR: 0.15, p < 0.001 and OR: 0.19, p < 0.001, respectively). Multivariate analysis confirmed the association of SLC19A1 80G and regular folic acid supplementation to gastrointestinal toxicity (OR: 5.53 and 0.13, respectively). Moreover, a multivariate Cox regression model demonstrated a higher risk of earlier gastrointestinal toxicity in SLC19A1 80G carriers (hazard ratio: 3.63, p = 0.002).

CONCLUSION

SLC19A1 G80A genotyping may be a useful tool for clinicians to identify patients at higher risk for developing gastrointestinal toxicity related to MTX treatment.

Increased levels of autoantibodies against catalase and superoxide dismutase associated with oxidative stress in patients with rheumatoid arthritis and systemic lupus erythematosus

OBJECTIVE

To evaluate the level of autoantibodies against superoxide dismutase (SOD) and catalase (CAT) in the sera of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) Tunisian patients, to study the oxidative profile among the same patients and to establish a correlation between the two parameters in order to understand the role of each one in the genesis of the two diseases.

METHOD

Using a standard enzyme-linked immunosorbent assay (ELISA), the levels of immunoglobulin G (IgG) and IgM directed against CAT and SOD in the sera of 39 RA patients, 40 SLE patients, and 50 control healthy individuals were evaluated. The oxidative/antioxidative profile was tested by measuring serum malondialdehyde (MDA), conjugated dienes (CD), CAT activity, and SOD activity.

RESULTS

Our data showed increased levels of IgG antibodies (Ab) against CAT in both groups of patients (p<0.05) compared to control subjects. However, the SLE patients displayed an increased level of anti-SOD IgG (p<0.05). In all patients the lipid peroxidation was confirmed by high levels of MDA and conjugated dienes (p<0.05). RA patients exhibited an increasing CAT and SOD activity in their sera (p<0.05) with a positive correlation observed between CAT and IgG anti-CAT (p<0.05). The same results were observed for SLE patients. In addition, a positive correlation was observed between anti-CAT Ab and anti-SOD Ab in SLE patients (p<0.05).

CONCLUSION

Collectively, these results suggested that the primary factor causing the oxidative stress observed in RA and SLE is excessive free radical production rather than impaired CAT or SOD activity due to autoantibody inhibition.

Protective effect of Withania somnifera root powder in relation to lipid peroxidation, antioxidant status, glycoproteins and bone collagen on adjuvant-induced arthritis in rats

The present investigation was carried out to evaluate the protective effect of Withania somnifera Linn. Dunal (family-Solanaceae), commonly known as Ashwagandha, on adjuvant-induced arthritic rats. Results were compared with those for Indomethacin, a nonsteroidal anti-inflammatory drug. Arthritis was induced by intradermal injection of complete Freund's adjuvant (0.1 mL) into the right hind paw of Wistar albino rats. Withania somnifera root powder (1000 mg/kg/day) and Indomethacin (3 mg/kg/day) were orally administered for 8 days (from 11th to 18th day) after adjuvant injection. The anti-arthritic effect of W. somnifera root powder was assessed by measuring changes in lipid peroxidation, antioxidant status, and glycoprotein levels in plasma and spleen of arthritic animals. In addition, cartilage degradation was also assessed by estimating bone collagen, and urinary constituents in arthritic animals. Results of the present investigation showed significant increase in the level of lipid peroxides, glycoproteins, and urinary constituents with the depletion of antioxidant status and bone collagen in arthritic animals. These biochemical alterations observed were ameliorated significantly by oral administration of W. somnifera root powder (1000 mg/kg body weight) in arthritic animals. The results of this study clearly indicate that W. somnifera root powder is capable of rectifying the above biochemical changes in adjuvant arthritis.

Inhibitory effect of inflammatory cytokines production from activated mast cells by Gamisopoonghwanghyul-tang

Rheumatoid arthritis (RA) is a chronic inflammatory disease and its exact cause and pathophysiological process remain unclear. Because the mast cell contains potent mediators, including multifunctional cytokines, its potential contributions to the processes of inflammation and matrix degradation have recently become evident. Gamisopoonghwanghyul-tang (GSPHHT) has been used as a traditional Korean medicine for the treatment of RA. In this study, we investigated the effect of Gamisopoonghwanghyul-tang (GSPHHT) on the production of inflammatory cytokines by activated human mast cell line HMC-1 cells. When GSPHHT (1 mg/ mL) was added, the production of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, IL-10 was inhibited by 36.3%, 36.3%, 30.8%, 48.7% respectively in phorbol 12-myristate 13-acetate plus calcium ionophore A23187-stimulated HMC-1 cells. However, the production of IL-4 was significantly increased at 0.01 mg/mL. GSPHHT had no effect on TNF-alpha mRNA expression. These results suggest that GSPHHT regulates production of inflammatory cytokines from activated mast cells.

Cheongyeolsaseuptang inhibits production of TNF-alpha, IL-6 and IL-8 as well as NF-kappa B activation in human mast cells

Traditional Korean medicine, Cheongyeolsaseuptang (CYSST) has been widely applied as a treatment of rheumatoid arthritis (RA) in Korea. However, its effect in experimental models remains unknown. Recent reports suggest that in patients with RA, synovial mast cells increase in number and show signs of activation and production of cytokines. In this study, we investigated the effect of CYSST on production of cytokines by activated human mast cell line, HMC-1. When CYSST (1mg/ml) was added, the production of tumor necrosis factor-alpha, interleukin (IL)-6, and IL-8 was significantly inhibited about 37, 33.6, and 48%, respectively on phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated HMC-1 cells. In addition, CYSST inhibited PMA plus A23187-induced activation of nuclear factor-kappaB. These findings may help understanding the mechanism of action of this medicine leading to control activated mast cells on inflammatory condition like RA.

OK205 regulates production of inflammatory cytokines in HMC-1 cells

OK205 is a traditional Korean prescription containing water-soluble chitosan, glucosamine HCl, chondroitin sulfate, and extract of herbal medicine, and has been used commercially to treat rheumatoid arthritis (RA). Because infiltrated mast cells and their mediators may contribute to the initiation and progression of the inflammatory process and matrix degradation of RA, we tested the inhibitory effects of OK205 on cytokine production in a human mast cell line (HMC-1 cells). Production of tumor necrosis factor-alpha was significantly decreased to 0.091+/-0.010 ng/ml after treatment of HMC-1 cells with OK205 100 microg/ml. The inhibition rate was about 43.57%. In addition, production of interleukin-6 in OK205 1 pg/ml-treated cells was 2.779+/-0.071 ng/ml, and the inhibition rate was about 50.22%. However, OK205 did not significantly inhibit the production of interleukin-8. These findings may help in understanding the mechanism of action of OK205, leading to control of mast cells in inflammatory conditions like RA.

Antioxidant status in rheumatoid arthritis and role of antioxidant therapy

BACKGROUND

Oxygen free radicals have been implicated as mediators of tissue damage in patients of rheumatoid arthritis (RA). This study was designed to elucidate plasma oxidant/antioxidant status in rheumatoid arthritis, with the aim of evaluating the importance of antioxidant therapy in the management of this disease.

METHODS

The study included 40 patients of rheumatoid arthritis who were randomly divided into two subgroups of 20 each. One group received conventional treatment for 12 weeks and in the other group conventional treatment was supplemented with antioxidants for the same duration. Twenty age- and sex-matched normal individuals constituted the control group. Blood samples of controls and patients were collected at the time of presentation and analyzed for total thiols, glutathione, vitamin C and malondialdehyde (MDA-marker of oxidative stress). The investigations were repeated in the patients after 12 weeks.

RESULTS

The blood concentrations of total thiols, glutathione and vitamin C were found to be significantly lower in rheumatoid arthritis patients as compared to healthy controls, while the concentrations of MDA were much higher. There was a statistically significant increase in the posttreatment concentrations of these antioxidants, along with a decrease in the concentrations of MDA.

CONCLUSIONS

The antioxidant defense system is compromised in rheumatoid arthritis patients. There is a shift in the oxidant/antioxidant balance in favor of lipid peroxidation, which could lead to the tissue damage observed in the disease. The results suggest the necessity for therapeutic co-administration of antioxidants along with conventional drugs to such patients. However, due to the limited number of cases included in this study, more studies may be required to substantiate the results and arrive at a definite conclusion, in terms of safety and efficacy of adding on antioxidant therapy for the treatment of RA.

Madimadi, Korean folk medicine, blocks TNF-α, IL-1β, and IL-8 production by activated human immune cells

Madimadi, a Korean folk medicine, has been applied to treat rheumatoid arthritis (RA). However, its mechanisms of action have not been examined. The involvement of inflammatory cytokines, particularly TNF-alpha, IL-1beta, and IL-8, resulting in local inflammation in the pathogenesis of RA is now widely accepted. Madimadi dose-dependently inhibited TNF-alpha, IL-1beta, and IL-8 production from activated human mast cells (HMC-1). RT-PCR revealed inhibition of TNF-alpha and IL-1beta transcription in activated HMC-1. In addition, we confirmed potent inhibition of TNF-alpha and IL-1beta production by Madimadi using purified human blood PBMC from an active RA group, but not from healthy or disease control groups. These novel insights into the immunosuppressive action of Madimadi are likely to impact the clinical use of this agent.

The Oriental Medicine 'Cool-Cool (Cool-X-A)' Inhibits Inflammatory Cytokine Production and Migration in Mast Cells

Plant medications have been applied to treat pains from various types of arthritis in Korea. Rheumatoid arthritis (RA) is well known to be a chronic autoimmune/inflammatory disease that leads to progressive joint damage and cartilage destruction. Accumulation and activation of mast cells have been demonstrated in rheumatoid synovial tissue. Because infiltrated mast cells and their mediators may contribute to the initiation and progression of the inflammatory process and matrix degradation of RA, we tested the inhibitory effects of "Cool-Cool" (CC, Cool-X-A), an Oriental medication, on the production and migration of major inflammatory cytokines in mast cells. CC was treated in vitro before activation of human mast cell line (HMC-1) with phorbol 12-myristate 13-acetate, and the cytotoxicity of CC was assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazoliumbromide assay. CC had no cytotoxic effects on HMC-1 cell viability. The inhibitory effects on cytokine production were monitored by enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction (RT-PCR). CC inhibited not only the secretion but also the expression of TNF-alpha and IL-8 in HMC-1 cells. CC also suppressed migration of mast cells induced by stem cell factor. These findings may help in understanding the mechanism of action of this herbal medication, leading to the control of mast cells in inflammatory conditions like RA.

Association of TAP2 gene polymorphisms in Chinese patients with rheumatoid arthritis

The aim of this study was to investigate the association between the polymorphism of transporters associated with antigen processing ( TAP1/TAP2) genes and rheumatoid arthritis in Chinese patients. A total of 100 RA patients and 99 healthy control subjects were enrolled. Analyses with polymerase chain reaction (PCR) based restrictions were used to identify the polymorphisms of the TAP1 and TAP2 genes, which were mapped on chromosome 6. There was a significant difference in the distribution of the TAP2 gene codon 565 polymorphism frequency between the RA patients and healthy control subjects ( p<0.001). The odds ratio for the risk of the 'A' allele in RA patients was 1.60 (95% CI: 0.82-2.92). No statistical associations in the distribution of the TAP1 gene polymorphism frequency were found between RA patients and controls. There were some physical links found between TAP1/TAP2 gene polymorphism loci. However, there was no linkage observed from TAP1/TAP2 gene polymorphisms and HLA-DRB1*04 between RA patients and healthy controls. We concluded that the TAP2 gene codon 565 'A' allele was associated with RA in Chinese patients in Taiwan. Individuals possessing the 'A' allele had a higher incidence of RA. A lack of association of TAP1 gene polymorphisms between RA patients and healthy individuals was noted. The results of this study provide genetic evidence that TAP2 gene codon 565 polymorphism may play a role in RA.

Daeganghwal-tang inhibits the stem cell factor-induced migration and inflammatory cytokines secretion in mast cells

Traditional Oriental medicinal prescription, Daeganghwal-tang (DGHT) has been used for the treatment of rheumatoid arthritis (RA) in Korea. However, its effect in experimental models remains unknown. Recent reports suggest that in patients with RA, synovial mast cells increase in number and show signs of activation and inflammatory cytokines secretion. Our results show that stem cell factor (SCF) is a potent chemotactic factor for the mast cells in vitro. The chemotactic response to SCF was blocked by DGHT. When DGHT (1mg/ml) was added, the secretion of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 was inhibited by 60.1, 81.8, 72.5%, respectively in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated HMC-1 cells. In addition, the expression of TNF-alpha mRNA in HMC-1 cells was inhibited by DGHT (1mg/ml). These findings indicate that DGHT inhibits SCF-induced migration and PMA plus calcium ionophore-stimulated inflammatory cytokines secretion in mast cells.

Change in cellular localization of a rheumatoid arthritis-related antigen (RA-A47) with downregulation upon stimulation by inflammatory cytokines in chondrocytes

We previously isolated a rheumatoid arthritis-related antigen (RA-A47) protein that had reactivity with RA sera from a human chondrosarcoma-derived chondrocytic cell line, HCS-2/8. Sequencing analysis of ra-a47 cDNA revealed RA-A47 as a product of the colligin-2 gene, which is also known as the human heat shock protein (HSP) 47 gene. Expression of hsp47 has been shown to be cooperatively altered with that of collagen genes upon stimulation. In this study, it was confirmed that the mRNA expression of ra-a47 and COL2A1, a type II collagen gene, was upregulated on stimulation with transforming growth factor (TGF) beta in chondrocytes. However, in contrast, inflammatory cytokines such as tumor necrosis factor (TNF) alpha, interferon (IFN) beta, and interleukin (IL)-6 downregulated the expression of ra-a47 mRNA, whereas the expression of COL2A1 mRNA was not repressed, or even upregulated, in HCS-2/8 cells. Of note, inducible NO synthase (iNOS) and matrix metalloproteinase (MMP)-9 mRNAs were strongly stimulated by TNFalpha. We also found that cell-surface type II collagen disappeared upon such a stimulation, suggesting that decrement of RA-A47 may inhibit the secretion of type II collagen and lead to its accumulation inside the cells. RA-A47 was detected in the cultured medium of TNFalpha-treated HCS-2/8 cells and of IL-1-treated rabbit chondrocytes by Western blot analysis. Under the same conditions, RA-A47 was detected on the cell surface by immunofluorescence staining. These findings demonstrate that the RA-A47 chaperone protein is specifically downregulated, causing the intracellular accumulation of unsecretable type II collagen, while the extracellular matrix (ECM) is degraded by MMPs and iNOS through the stimulation of chondrocytes by TNFalpha. The altered localization of RA-A47 to the surface or outside of cells may represent the mechanism for the recognition of RA-A47 as an autoantigen during rheumatoid arthritis.

Macrophage migration inhibitory factor up-regulates expression of matrix metalloproteinases in synovial fibroblasts of rheumatoid arthritis

Neutral matrix metalloproteinases (MMPs) are responsible for the pathological features of rheumatoid arthritis (RA) such as degradation of cartilage. We herein show the up-regulation of MMP-1 (interstitial collagenase) and MMP-3 (stromelysin) mRNAs of cultured synovial fibroblasts retrieved from rheumatoid arthritis (RA) patients in response to macrophage migration inhibitory factor (MIF). The elevation of MMP-1 and MMP-3 mRNA was dose-dependent and started at 6 h post-stimulation by MIF, reached the maximum level at 24 h, and was sustained at least up to 36 h. Interleukin (IL)-1beta mRNA was also up-regulated by MIF. These events were preceded by up-regulation of c-jun and c-fos mRNA. Tissue inhibitor of metalloproteinase (TIMP)-1, a common inhibitor of these proteases, was slightly up-regulated by MIF. Similarly, mRNA up-regulation of MMP-1 and MMP-3 was observed in the synovial fibroblasts of patients with osteoarthritis. However, their expression levels were much lower than those of RA synovial fibroblasts. The mRNA up-regulation by MIF was inhibited by the tyrosine kinase inhibitors genestein and herbimycin A, as well as the protein kinase C inhibitors staurosporine and H-7. On the other hand, the inhibition was not seen after the addition of the cyclic AMP-dependent kinase inhibitor, H-8. The mRNA up-regulation of MMPs was also inhibited by curcumin, an inhibitor of transcription factor AP-1, whereas interleukin-1 receptor antagonist, an IL-1 receptor antagonist, failed to inhibit the mRNA up-regulation. Considering these results, it is suggested that 1) MIF plays an important role in the tissue destruction of rheumatoid joints via induction of the proteinases, and 2) MIF up-regulates MMP-1 and MMP-3 via tyrosine kinase-, protein kinase C-, and AP-1- dependent pathways, bypassing IL-1beta signal transduction.

Tumor necrosis factor alpha promotes the expression of stem cell factor in synovial fibroblasts and their capacity to induce mast cell chemotaxis

OBJECTIVE

To investigate the expression of the stroma cell product stem cell factor (SCF) in synovial fibroblasts (SFB) in patients with rheumatoid arthritis (RA) and osteoarthritis (OA), and to analyze the capacity of SFB to induce mast cell (MC) chemotaxis.

METHODS

Synovial tissue was obtained from 29 patients with RA and 25 patients with OA. Tissue was dispersed by enzymatic digestion using collagenase. SFB were grown in serial passage and exposed to tumor necrosis factor alpha (TNFalpha) or control medium. Expression of SCF in cultured SFB was analyzed by reverse transcription-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and immunostaining. The ability of SFB (supernatants) to induce MC migration was analyzed using a double-chamber chemotaxis assay and the human mast cell line HMC-1. In situ expression of SCF in synovial tissue from patients with RA (n = 6) and OA (n = 6) was examined by double immunohistochemistry using antibodies against SCF and the fibroblast-specific antibody AS02.

RESULTS

In both RA and OA, cultured SFB were found to express SCF messenger RNA, as assessed by RT-PCR. In addition, the SCF protein was detectable in cell lysates and supernatants of SFB by ELISA. Incubation of SFB with TNFalpha resulted in an increased expression and release of SCF. Recombinant human SCF (rHuSCF) and SFB supernatants induced significant migration of HMC-1 cells above control levels. In addition, exposure of SFB to TNFalpha led to an increased migration of HMC-1, and a blocking anti-SCF antibody inhibited the rHuSCF- and SFB-induced migration of HMC-1. In situ double immunostaining revealed expression of SCF in AS02-positive SFB in the synovium of patients with RA.

CONCLUSION

Our results show that SFB (in RA and OA) express SCF and induce MC chemotaxis. Furthermore, TNFalpha was found to augment SCF expression in SFB. It is hypothesized that these cellular interactions play an important role in MC accumulation and related events in RA.

The participation of IL-8 in the synovial lesions at an early stage of rheumatoid arthritis

Synovial tissues from Rheumatoid Arthritis (RA) were divided into three groups based on their histopathological findings and compared for their expression of IL-8 and monocyte chemotactic and activating factor (MCAF) by using immunohistochemistry and in situ hybridization. The levels of IL-8 as well as those of MCAF were markedly higher in the synovial fluid from RA joints. Synovial lining cells (SLC) and macrophages had an ability to produce IL-8 at an early phase of the disease. The presence of MCAF was restricted in macrophages at this stage. On the other hand, the production of IL-8 as well as MCAF were prominent in most components of the joints such as SLC, migrated monocytes, sublining fibroblastoid cells, endothelial cells or migrated neutrophils at an active phase. The expression of IL-8 or MCAF was low in fibrotic synovitis of RA. These data indicate that IL-8 generated from SLC and macrophages may participate to the inflammatory process in the early synovitis of RA.

Rheumatoid Pannus of the Cervical Spine: A Case Report of an Unusual Cause of Dysphagia

Dysphagia as an initial complaint in rheumatoid arthritis is rare. We describe the case of a 69-year-old woman with rheumatoid arthritis who presented with a 2-day history of acute dysphagia. Our evaluation revealed the cause of the dysphagia was the presence of rheumatoid pannus that involved the anterior cervical spine and compressed the esophagus. Although the otolaryngologic manifestations of rheumatoid arthritis usually relate to synovial involvement of the temporomandibular and cricoarytenoid joints, our case establishes that a rheumatoid pannus on the anterior cervical spine can cause dysphagia. We believe that this may be the first reported case of this clinical entity.

Expression of the C5a receptor (CD88) on synovial mast cells in patients with rheumatoid arthritis

OBJECTIVE

To analyze the immunophenotype and functional properties of synovial mast cells (SyMC) in patients with rheumatoid arthritis (RA) and osteoarthritis (OA).

METHODS

Synovial tissue was obtained from 25 patients with RA and 17 patients with OA. Tissue was dispersed by enzymatic digestion using collagenase. Surface receptor expression on SyMC was analyzed by monoclonal antibodies (MAb) and indirect immunofluorescence staining. Histamine release experiments were performed using the MC agonist recombinant human (rHu) stem cell factor (SCF), the anaphylatoxin rHuC5a, and an anti-IgE antibody.

RESULTS

In both groups of patients (RA and OA), SyMC were found to react with MAb to IgE, SCF receptor (c-kit, CD117), as well as CD antigens likewise expressed in lung MC (CD9, CD29, CD33, CD43, CD44, CD45). However, a significantly increased proportion of SyMC from RA patients reacted with MAb against C5a receptor (C5aR; CD88), compared with SyMC from OA (mean +/- SD percentage of SyMC reacting with CD88 MAb S5/1 in RA 27.5 +/- 8.6% versus 0.0% in OA, and with CD88 MAb W17/1 in RA 58.3 +/- 15.2% versus 12.5 +/- 15.0% in OA; P < 0.05). Furthermore, in RA, significant histamine release from SyMC above control was induced by rHuC5a, anti-IgE, and rHuSCF, whereas SyMC in OA released histamine after stimulation with anti-IgE and rHuSCF, but not rHuC5a.

CONCLUSION

SyMC exhibit phenotypic and functional properties similar to MC in other tissues. In patients with RA, but not OA, SyMC express significant amounts of C5aR (CD88) and release histamine in response to rHuC5a. These results indicate a role for SyMC and C5a/C5aR in the pathogenesis of RA.

T cell receptor delta locus polymorphism in rheumatoid arthritis

In order to identify new susceptibility markers for Rheumatoid Arthritis (RA), we analysed the dinucleotide repeat polymorphism at the T cell receptor delta locus (TCRD) in 65 RA patients and 99 healthy Belgian controls. A significant under-representation of the A4-A5 TCRD genotype was observed in the RA population.

HLA class II and T-cell receptor beta chain polymorphisms in Belgian patients with rheumatoid arthritis: no evidence for disease association with the TCRBC2, TCRBV8 and TCRBV11 polymorphisms

OBJECTIVES

To investigate whether T-cell receptor (TCR) beta chain germline alleles, either alone or in combination with a particular HLA-genotype, are associated with rheumatoid arthritis (RA).

METHODS

Three restriction fragment length polymorphisms (RFLPs), detected with TCR constant (TCRBC2) and variable (TCRBV8, TCRBV11) gene segments were analysed in a representative group of Belgian, HLA class II-typed patients with RA, and in a group of Belgian control subjects.

RESULTS

The study confirmed the known association of RA with the HLA-DRB1*0401/0404 genotype (RR = 2.14, 95% CI = 1.16-4.00) in the Belgian RA population. This association was even more pronounced in the patients with more severe RA (RR = 3.26, 95% CI = 1.55-6.89). These data suggest that the HLA-DRB1*04 genotype can be used as a marker for disease severity. Similar frequencies in patients and controls were observed for all TCRB RFLPs studied, and this was in spite of subgrouping the RA population according to criteria for disease stratification.

CONCLUSION

While a clear association with HLA DRB1*0401/0404 is observed, no interactive effects were seen with RA, DR4, TCRBC2 and TCRBV alleles, implying that the combined presence of these polymorphic markers does not cause an increased susceptibility to RA, and does not predispose for more aggressive RA, nor for familial aggregation of the disease. These results argue against the hypothesis that TCRB polymorphisms play a crucial role in the susceptibility for RA.

Fibronectin and lymphocytes in inflammatory tissue. Studies of blood and synovial fluid lymphocytes from patients with rheumatoid arthritis and other inflammatory arthritides

Lymphocytes infiltrating tissues under chronic inflammatory conditions are often surrounded by deposits of fibronectin. We have studied the possibility that this reflects capacity of lymphocytes to synthesize fibronectin and compared lymphocytes from blood and synovial fluid with respect to fibronectin interactions. In vitro activated blood lymphocytes exhibited synthesis of a fibronectin-like molecule. Synovial fluid cells appeared to synthesize the same high molecular weight component spontaneously. Activated blood lymphocytes have cell surface fibronectin and surface components of lower molecular weight which could be immunoprecipitated with anti-fibronectin antibodies as well as by insolubilized collagen. Synovial fluid cells showed cell surface fibronectin as revealed by immunocytochemical detection but seemed to lack or have relatively small amounts of the low-molecular weight fibronectin-like surface components. Synovial fluid T cells from arthritis patients showed adhesion to fibronectin. Immunocytochemistry demonstrated presence of alpha 4 and alpha 5 beta 1 integrins at the surface of the synovial fluid T cells and RGD and LDV peptides inhibited adhesion of the cells to fibronectin. Noteworthy, a portion of synovial fluid cells with lymphocyte markers also bound to plastic. Blood lymphocytes from the same arthritis patients displayed relatively poor or negligible adhesion to fibronectin unless activated to blast transformation and did not attach to plastic. Taken together these results suggest that activated lymphocytes from blood and synovial fluid may use fibronectin of exogenous or endogenous origin when interacting with tissues during inflammatory processes. Furthermore, the presence at the lymphocyte surface of components of different molecular weight precipitated by anti-fibronectin antibodies suggests that fibronectin or its fragments can bind to the lymphocyte surface.

IgG3 reactive rheumatoid factor in rheumatoid arthritis: etiologic and pathogenic considerations

Rheumatoid factor (RF) is a polyclonal autoantibody directed against the Fc portion of IgG. Although the role of RF in patients with rheumatoid arthritis (RA) is unclear, immune complexes that form between RF and IgG can activate the classical complement (C) pathway, leading to pathogenic outcomes involving inflammatory events and tissue damage. The specificity of serum RF and RF produced by rheumatoid synovial cells (RSC) is different. Serum RF has specificity for rabbit IgG and human IgG subclasses IgG1, 2, and 4, but binds poorly to IgG3. The affinity of serum RF for IgG Fc is low, having an association constant of 10(4)-10(5) M-1. RSC RF, however, has specificity for human IgG and high avidity for IgG3. Because of this greater specificity and avidity for IgG3, and because RSC RF may be pathogenically more important than serum RF, an important role for IgG3-reactive RF in RA may exist. Binding of RF to IgG may be dependent on the allotype and glycosylation of IgG. Infectious agents present in RA patients may directly or indirectly induce the production of certain RF. In this communication, we review and expand on several observations examining the role of IgG3-reactive RF in RA including: 1) binding differences between RF derived from RSC and serum; 2) glycosylation characteristics of IgG and its interaction with RF; 3) apparent allotype dependent binding of IgG3-reactive RF; and 4) possible relationship between infectious agents and the production of IgG3-reactive RF. Taken together, these observations suggest an important role for IgG3-reactive RF in better understanding the etiology and pathogenesis of RA.

Rheumatoid arthritis in a population sample in the Gulf: clinical observations

In our practice we had constantly been under the impression that most Arab patients with RA tend to have a non-aggressive and rather nondisabling disease. Therefore, the spectrum of RA was studied in 42 hospital patients with classic or definite forms. Their mean age was 41.2 years and the mean duration of illness was 5.25 years. F:M ratio was 3.6:1. Seropositivity and radiological findings were observed in 59.5% and 45.2% of the patients respectively. They showed a marked lack of nonarticular manifestations with insignificant functional incapacity. The over-all assessment appeared to be in agreement with the initial clinical impression.

Synovial mononuclear phagocytes in rheumatoid arthritis and osteoarthritis: quantitative and functional aspects

Macrophages are normal constituents of synovial tissue, and in inflammatory synovitis the number of synovial macrophages increases. Synovial macrophages and their secretory products are important in initiating, propagating, and maintaining the synovial inflammation in rheumatoid arthritis (RA). The purpose of this study was to determine the absolute numbers of macrophages in synovia resected from patients with RA and osteoarthritis (OA) and to determine their abilities to produce and/or functionally express tumor necrosis factor (TNF), interleukin-1 (IL-1), and tissue factor (thromboplastin). Results demonstrate that synovial tissue from RA patients (as compared to that from OA patients) weighed more, contained more cells, more macrophages, and more multinucleated giant cells (macrophage polykaryons). Also, isolated cells from both OA and RA patients had tissue factor activity and could produce TNF and IL-1 with in vitro culture, but these parameters were not different in cells from OA and RA patients. RA patients receiving glucocorticoid treatment for their arthritis had fewer total synovial cells than did patients not on glucocorticoids, but treatment with nonsteroidal anti-inflammatory agents did not alter cell numbers. Patient treatment with glucocorticoids or non-steroidal anti-inflammatory drugs did not influence the ability of their isolated cells to produce TNF or IL-1.

Antilipoprotein antibodies in rheumatoid arthritis

Antibodies against very low-density lipoproteins and low-density lipoproteins (aLA) were found in 26 of 69 (38%) patients with active rheumatoid arthritis (RA) but not in any control subjects (ie, 40 patients with psoriatic arthritis, 21 patients with osteoarthritis, and 65 healthy blood donors). In 21 RA patients (30%), lipoproteins were found in the dissociated components of circulating immune complexes. RA patients with aLA had significantly decreased cholesterol levels in all lipoprotein fractions and total serum lipids, while serum triglycerides were significantly increased compared with RA patients without aLA. Anticardiolipin antibodies as measured by the Venereal Disease Research Laboratory test were not found in any subject in this study. These findings suggest a possible autoimmune origin of dyslipoproteinemia in some patients with active RA.

Protective effect of androgens against inflammation induced cartilage degradation in male rodents

OBJECTIVES

Rheumatoid arthritis (RA) is a disease which predominantly affects women. Interestingly, low serum androgen levels and clinical improvement with androgen replacement have been reported in male patients. The aetiopathogenic role of sex hormones in arthritis and their potential long term effects on joint destruction and disability remains unclear, however. This study was designed to investigate the potential influence of sex hormones on inflammation induced cartilage degradation in male rodents.

METHODS

An in vivo model of cotton wrapped cartilage implants was used to assess the effects of androgen, oestradiol, and progesterone on inflammation induced cartilage degradation, and in vitro techniques were used to investigate the direct actions on cartilage metabolism and cytokine production in male animals.

RESULTS

Orchidectomy resulted in accelerated cartilage damage which was reversed by replacement of physiological levels of androgens. Granulomatous tissue from castrated male rodents produced higher amounts of interleukin 1. Sex hormones reduced spontaneous proteoglycan loss in vitro but did not interfere with the effects of interleukin 1 on cultured cartilage.

CONCLUSIONS

Androgens appear to protect cartilage from inflammation induced breakdown in male animals. These results support a pathogenic role for hypoandrogenism in rheumatoid arthritis and suggest that long term androgen replacement may help prevent joint damage and disability.

Expression of human tenascin in synovitis and its regulation by interleukin-1

OBJECTIVE

Tenascin is an extracellular matrix glycoprotein with effects on cell adhesion, cell migration, and lymphocyte activation. We proposed to identify the expression of human tenascin messenger RNA (mRNA) and protein in inflammatory synovitis and in normal synovium, and to identify potential regulatory cytokines.

METHODS

Immunohistochemistry and in situ hybridization were used to identify the expression of tenascin in synovium. Northern blot analysis of RNA and both immunoblot analysis and enzyme-linked immunosorbent assay of proteins were used to identify tenascin in synovial cell cultures.

RESULTS

Tenascin was found along the synovial lining layer and in perivascular areas of normal synovium. In inflammatory synovitis, tenascin protein and mRNA expression were shown to be increased in the synovial lining layer, in perivascular areas, in lymphoid aggregates, and in areas of fibrosis. Interleukin-1, a major mediator of tissue injury in inflammatory synovitis, induced tenascin expression and deposition in primary synovial fibroblast cultures.

CONCLUSION

Tenascin mRNA and protein are increased in inflammatory synovitis, and interleukin-1 is an inducer of tenascin in synovial fibroblasts. This identifies a new pathway by which interleukin-1 alters the extracellular matrix composition in synovitis. Since tenascin has effects on lymphocyte activation and cell adhesion, the induction of tenascin in inflammatory synovitis may play a role in the pathophysiology of arthritis.

Effect of gold compounds on the activity of adenylyl cyclase in human lymphocyte membranes

OBJECTIVE

To determine the effects of aurothioglucose, aurothiomalate, and auranofin on basal and forskolin-activated adenylyl cyclase activity in human total lymphocyte membranes, and in membranes of T and B lymphocyte subsets.

METHODS

Membranes were isolated from human total lymphocytes and T and B cell subsets. The effects of gold compounds on basal and forskolin-stimulated activity of adenylyl cyclase were measured by radioassay.

RESULTS

The gold compounds inhibited adenylyl cyclase activity. This inhibitory effect required the presence of both the sulfhydryl ligands and aurous cation.

CONCLUSION

Regulation of lymphocyte adenylyl cyclase by gold compounds represents a potential mode of action of these drugs in rheumatic diseases.

Intra-articular rheumatoid nodules and triggering of the knee joint

Rheumatoid nodules are a common extra-articular manifestation in rheumatoid arthritis. Intra-articular localisation of these nodules is rare and may produce clinical symptoms. Seven patients with walking problems due to an intra-articular rheumatoid nodule, which became entrapped on the ridge of the tibial plateau of the knee joint resulting in a phenomenon referred to as trigger knee, are described. After excision of the nodules all symptoms completely disappeared.

Differences in t cell receptor restriction fragment length polymorphisms in patients with rheumatoid arthritis

OBJECTIVE

The purpose of this study was to determine whether a T cell receptor (TCR) polymorphism, either by itself or in combination with particular HLA polymorphism, leads to susceptibility to rheumatoid arthritis (RA).

METHODS

Eight restriction fragment length polymorphisms (RFLPs) detected with TCR gene segments were investigated in 46 individuals with RA and were compared with data from normal control subjects.

RESULTS

A statistically significant difference in the genotype frequencies of a Taq I RFLP detected with the TCR alpha constant region (C alpha) gene was noted. In addition, when the DR4+ subpopulations were examined, the allelic frequency of a 2-kb Bam HI fragment detected with a V beta 8 gene was increased in the samples from RA patients (P less than 0.0086).

CONCLUSION

The results of this study suggest that germline differences in the TCR repertoire may be associated with RA, and that there is a contributory effect of DR4+ haplotypes with certain TCR haplotypes in susceptibility to RA.

Expression of metalloproteinases and metalloproteinase inhibitor in human arthritic synovium

The expression of messenger RNA encoding neutral metalloproteinases and the tissue inhibitor of metalloproteinases (TIMP) in human arthritic synovium was evaluated in situ, using RNA probes. Interstitial collagenase and stromelysin were expressed by synovial lining cells in patients with active rheumatoid arthritis (RA). Proteinase messenger RNA was found both in cells expressing mononuclear phagocyte antigens and in cells that were negative for the antigens. TIMP was also expressed predominantly along the synovial lining layer. In highly inflammatory RA, TIMP expression appeared less intense than that of the proteases. In osteoarthritic synovium, TIMP was expressed at easily detectable levels, whereas the expression of collagenase and stromelysin was less prominent. The balance between expression of the metalloproteinases and of the metalloproteinase inhibitor in synovium appears to be altered during inflammation. These results are consistent with the notion that synovium plays different roles in the cartilage damage of RA and of osteoarthritis.

Extravascular fibrin formation and dissolution in synovial tissue of patients with osteoarthritis and rheumatoid arthritis

Fibrin deposition is a prominent finding in the synovium of patients with rheumatoid arthritis (RA). Macrophages are found in increased numbers in RA synovium, and these cells are known to produce a variety of procoagulant and anticoagulant molecules. Using immunohistologic techniques, the content and distribution of several important components of the coagulation system in the synovium of patients with RA, osteoarthritis (OA), or traumatic joint abnormalities requiring surgery were investigated. Samples from 3 patients from each category were examined in detail. RA synovium (compared with that of patients with OA or joint trauma) had increased numbers of macrophages and increased expression/content of fibrinogen, tissue factor, factor XIII, tissue transglutaminase, cross-linked fibrin (fibrin D dimer), urokinase-type plasminogen activator, and alpha 2-plasmin inhibitor. Macrophage content in RA synovium was increased in both the lining cell areas and the interstitial cell areas. Fibrinogen was distributed throughout the tissue in all samples and was greater in RA synovium. In trauma and OA synovia, tissue factor was seen only in association with vessels (endothelial cells), but in RA synovium, it was markedly increased throughout the tissues. While fibrin D dimer was seen in small amounts in synovial lining cell areas of trauma and OA synovia, it was present in increased amounts in the lining cell and interstitial cell areas of RA synovium. Factor XIII and tissue transglutaminase were present in scant amounts in trauma and OA synovia, but there were increased amounts of both (especially tissue transglutaminase) in RA synovium in the vessel, lining cell, and interstitial cell areas. Urokinase and alpha 2-plasmin inhibitor were also markedly increased in RA synovium. These results suggest that in inflamed synovium, there is ongoing extravascular tissue fibrin formation and dissolution that correlates with the degree of inflammation and macrophage content. Extravascular coagulation/fibrinolysis in RA represents a potential target for therapeutic intervention in this disease.

Synovial membrane histology and immunopathology in rheumatoid arthritis and osteoarthritis. In vivo effects of antirheumatic drugs

We examined the histologic and immunopathologic features of the synovial membrane of 18 patients with rheumatoid arthritis (RA) and 12 patients with osteoarthritis (OA) who had undergone total knee arthroplasty. Patients were classified into 5 groups according to therapeutic regimen and disease: RA treated with nonsteroidal antiinflammatory drugs (NSAIDs), RA treated with NSAIDs and prednisone, RA treated with NSAIDs and methotrexate (MTX), OA treated with analgesics, and OA treated with NSAIDs. There were no significant between-group differences in the percentages or the distribution pattern of the infiltrating T cell subsets (CD4, CD8), HLA-DR, or interleukin-2 receptor-bearing cells. However, inflammatory indices, which included the thickness of the lining cell layer and the density of the mononuclear cell infiltrate, were significantly higher in the RA patients treated with prednisone and those treated with MTX (P less than 0.05). Similarly, fibrosis was markedly reduced in these 2 groups. The RA patients treated with NSAIDs alone and the 2 groups of patients with OA demonstrated similar profiles. These data suggest that prednisone and MTX may inhibit the development of fibrosis without altering the subsets of the inflammatory cell population. This observation raises the possibility that the action of these 2 drugs may be partly mediated by the suppression of inflammatory mediators that are responsible for fibroblast activation.

Effects of a hydrosoluble bacterial extract from Escherichia coli (OM-89) on cytokine production by peripheral blood mononuclear cells from healthy subjects and patients with rheumatoid arthritis

OM-89 is a bacterial extract from escherichia coli, proposed as an immunomodulating drug for the treatment of rheumatoid arthritis (RA). Since immunological mechanisms may play a role in its action, the immunological effects of OM-89 were evaluated in vitro on peripheral blood mononuclear cells (PBMC) derived from healthy subjects and RA patients. Results indicated that in the absence of OM-89, production of the monokines interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) is increased, while that of the lymphokines interleukin-2 (IL-2) and interferon-gamma (IFN-gamma is decreased by phytohemagglutinin (PHA)-stimulated PBMC from RA patients as compared with PBMC from healthy subjects. In the presence of PHA, OM-89 enhanced the production of IL-1 beta, TNF-alpha, IL-2, and IFN-gamma. IL-1 beta and IL-2 curves obtained using increasing amounts of OM-89 did not differ depending on the source of PBMC. By contrast, in the presence of increasing amounts of OM-89, TNF-alpha secretion significantly higher and IFN-gamma secretion significantly lower with PBMC from RA patients compared to PBMC from healthy subjects. These data indicate that OM-89 acts on monocytes and T cells directly and/or indirectly and suggest a possible clinical activity by OM-89 in RA relative to its immunological properties.

Localization of collagenase mRNA in rheumatoid arthritis synovium by in situ hybridization histochemistry

Collagenase has been implicated as playing an important role in the connective tissue destruction that is a major feature of rheumatoid arthritis. Numerous cell types in the hyperplastic rheumatoid synovium are capable of synthesizing collagenase. Past studies have used predominantly synovial fibroblasts in culture as a model system for the regulation of collagenase production, but the major cellular source of the enzyme in vivo has not been determined. Using the techniques of in situ hybridization histochemistry and indirect immunofluorescence, we determined the cellular source of collagenase in frozen sections of human synovium. Collagenase mRNA production was localized to cells along the synovial lining layer in rheumatoid arthritis. These were identified as the macrophage-like Type A synovial lining cells by immunofluorescence with antibody LeuM3. Endothelial cells, fibroblasts, and T and B lymphocytes were devoid of detectable collagenase mRNA. Synovial tissue sections from patients with osteoarthritis and trauma did not contain detectable collagenase mRNA. These data identify the Type A macrophage-like synovial lining cell as the primary source of collagenase mRNA in vivo in the rheumatoid arthritis synovium and, potentially, as a major effector cell in the tissue destruction of the disease.