Methotrexate reduces inflammatory cell numbers, expression of monokines and of adhesion molecules in synovial tissue of patients with rheumatoid arthritis

Standardisation of synovial tissue infiltrate analysis: how far have we come? How much further do we need to go?

Changes in cellular infiltrate and expression of cytokines, chemokines, and cell adhesion molecules as a result of therapeutic interventions in rheumatoid arthritis can be demonstrated in the synovial membrane. However, before synovial tissue analysis can be used as an outcome measure in such studies, standardisation of the site and method of synovial tissue acquisition, methods of tissue processing, and appropriate methods of detection and measurement of cell lineage specific markers and relevant biological proteins is needed.

Synovial biopsy

In patients with arthritis, synovial tissue is easily accessible for analysis. Blind needle biopsy is a simple and safe procedure. Arthroscopic biopsy is also safe, it allows access to most sites in the joint and it can provide adequate tissue for extensive laboratory investigations, both before and after successful therapy. Synovial tissue analysis has been successfully applied to the study of disease mechanisms and response to treatment. In addition, there may be an indication for diagnostic synovial biopsy in selected cases.

The changes in expression of ICAM-3, Ki-67, PCNA, and CD31 in psoriatic lesions before and after methotrexate treatment

Although the effectiveness of methotrexate (MTX) in the treatment of psoriasis is very well established, the mechanism of action is poorly understood. It was suggested that the therapeutic effect of MTX in psoriasis might be mediated by inhibition of adhesion molecule expression. The aim of our study was to investigate the different effects of MTX treatment on cell proliferation, inflammatory infiltrate, adhesion molecules, and angiogenesis in psoriasis, and to clarify the mechanism by which MTX exerts its therapeutic effects. Clinical response, the morpho-phenotypic changes, epidermal thickness, and mitosis count were analyzed and the expression of CD31 and ICAM-3, proliferative markers such as Ki-67, PCNA, were evaluated by immunohistochemical techniques in lesional psoriatic epidermis, before and after the treatment with MTX in ten patients. In posttreatment biopsies a decrease in the degree of epidermal hyperplasia and a significant reduction in the severity of the inflammatory infiltrate (P<0.05) were observed. In addition, CD31 and ICAM-3 expression was significantly decreased on dermal cellular infiltrate, (respectively; P<0.05, P<0.01). Ki67 and PCNA expression were suppressed concurrently in about 90% of cases (P<0.01). We suggest that MTX may have an inhibitory effect on an initial integral component of the pathways that lead to psoriasis. Immunopharmacologic intervention in adhesion event has the potential to improve psoriasis. Inhibition of revascularization may be another mechanism of action of MTX.

Modulation of Orphan Nuclear Receptor NURR1 Expression by Methotrexate in Human Inflammatory Joint Disease Involves Adenosine A2A Receptor-Mediated Responses

Modulation by proinflammatory mediators indicate that NURR1 induction represents a point of convergence of distinct signaling pathways, suggesting an important common role for this transcription factor in mediating multiple inflammatory signals. The present study identifies NURR1 as a molecular target of methotrexate (MTX) action in human inflammatory joint disease and examines the mechanism through which MTX modulates NURR1 expression. MTX significantly suppresses expression of NURR1 in vivo in patients with active psoriatic arthritis (n = 10; p < 0.002) who were prescribed low-dose MTX for management of peripheral arthritis. Importantly, reduction in NURR1 levels correlate (n = 10; r = 0.57; p = 0.009) with changes in disease activity score (both clinical and laboratory parameters). MTX selectively modulates NURR1 levels induced by inflammatory stimuli and growth factors in resident cell populations of synovial tissue. In primary human synoviocytes and microvascular endothelial cells, we observe dose-dependent differential effects of MTX on steady-state and inducible NURR1 levels. Our data confirms that adenosine, and its stable analog 5'-N-ethylcarboxamideadenosine, can mimic the differential effects of MTX on NURR1 transcription. In addition, we verify that the inhibitory effect of low-dose MTX on NURR1 activation is mediated through the adenosine receptor A2. More specifically, our data distinguishes the selective involvement of the A2A receptor subtype in these responses. In summary, these findings establish the nuclear orphan receptor NURR1 as a molecular target of MTX action in human inflammatory joint disease and demonstrate that the immunomodulatory actions of MTX on NURR1 expression are mediated through adenosine release.

Targeting cellular adhesion molecules, chemokines and chemokine receptors in rheumatoid arthritis

The development of specific targeted therapies, such as anti-TNF-alpha treatment, for chronic inflammatory disorders such as rheumatoid arthritis, has significantly improved treatment, although not all patients respond. Targeting cellular adhesion molecules and chemokines/chemokine receptors as regulators of the extravasation and migration of leukocytes may provide a novel approach for the treatment of these diseases. Moreover, the possibility of developing small-molecule antagonists offers an excellent method for the oral delivery of compounds with a short half-life.

Clinical efficacy of infliximab plus methotrexate in DMARD naive and DMARD refractory rheumatoid arthritis is associated with decreased synovial expression of TNF alpha and IL18 but not CXCL12

BACKGROUND

Tumour necrosis alpha (TNF alpha) blocking agents lead to pronounced clinical effects and reduced synovial infiltrate in rheumatoid arthritis. Laboratory and clinical studies suggest that TNF alpha independent pathways play a role in the disease.

OBJECTIVES

To evaluate the immunopathological effects of combination therapy on rheumatoid synovial tissue in order to identify TNF alpha independent mechanisms.

METHODS

12 rheumatoid patients, including four DMARD (disease modifying antirheumatic drug) naive patients with early disease, were studied for the effect of combination therapy with infliximab and methotrexate on the synovial infiltrate. Biopsies and clinical assessments (DAS28) were carried out before the first and after the third infusion of infliximab. Synovial inflammation was scored semiquantitatively. Co-expression of CD38(+) cells was studied by an immunofluorescent double labelling technique.

RESULTS

Marked clinical responses were associated with a global reduction in the synovial infiltrate and expression of cytokines, notably interleukin 18 and TNF alpha, but low grade disease activity persisted. There was no effect on the expression of CXC chemokine ligand (CXCL12), and germinal centre-like structures were still detectable in synovial tissue in two patients after treatment. CD38(+) activated T cells were more resistant to treatment than CD38(+) plasma cells. No differences in clinical response or effects on synovial infiltrate were observed between DMARD refractory and DMARD naive patients.

CONCLUSIONS

Persistent expression of CXCL12 and incomplete resolution of lymphocytic infiltrates after infliximab plus methotrexate indicates that TNF alpha independent mechanisms are operative in rheumatoid arthritis. This may contribute to low grade disease activity, even in DMARD naive patients with early disease.

Synovial histopathology of psoriatic arthritis, both oligo- and polyarticular, resembles spondyloarthropathy more than it does rheumatoid arthritis

At present only few biological data are available to indicate whether psoriatic arthritis (PsA) is part of the spondyloarthropathy (SpA) concept, whether it is a separate disease entity or a heterogeneous disease group with oligoarticular/axial forms belonging to SpA and polyarticular forms resembling rheumatoid arthritis (RA). To address this issue with regard to peripheral synovitis, we compared the synovial characteristics of PsA with those of ankylosing spondylitis (AS)/undifferentiated SpA (USpA) and RA, and compared the synovium of oligoarticular versus polyarticular PsA. Synovial biopsies were obtained from patients with RA, nonpsoriatic SpA (AS + USpA), and oligoarticular and polyarticular PsA. The histological analysis included examination(s) of the lining layer thickness, vascularity, cellular infiltration, lymphoid aggregates, plasma cells and neutrophils. Also, we performed immunohistochemical assessments of CD3, CD4, CD8, CD20, CD38, CD138, CD68, CD163, CD83, CD1a, CD146, alphaVbeta3, E-selectin, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, S100A12, intracellular citrullinated proteins and major histocompatibility complex (MHC)-human cartilage (HC) gp39 peptide complexes. Comparing SpA (PsA + AS + USpA) with RA, vascularity, and neutrophil and CD163+ macrophage counts were greater in SpA (P < 0.05), whereas lining layer thickness and the number of CD83+ dendritic cells were greater in RA (P < 0.05). In RA, 44% of samples exhibited positive staining for intracellular citrullinated proteins and 46% for MHC-HC gp39 peptide complexes, whereas no staining for these markers was observed in SpA samples. We excluded influences of disease-modifying antirheumatic drug and/or corticosteroid treatment by conducting systematic analyses of treated and untreated subgroups. Focusing on PsA, no significant differences were observed between PsA and nonpsoriatic SpA. In contrast, vascularity (P < 0.001) and neutrophils were increased in PsA as compared with RA (P = 0.010), whereas staining for intracellular citrullinated proteins and MHC-HC gp39 peptide complexes was exclusively observed in RA (both P = 0.001), indicating that the same discriminating features are found in PsA and other SpA subtypes compared with RA. Exploring synovial histopathology between oligoarticular and polyarticular PsA, no significant differences were noted. Moreover, intracellular citrullinated proteins and MHC-HC gp39 peptide complexes, which are specific markers for RA, were observed in neither oligoarticular nor polyarticular PsA. Taken together, these data indicate that the synovial histopathology of PsA, either oligoarticular or polyarticular, resembles that of other SpA subtypes, whereas both groups can be differentiated from RA on the basis of these same synovial features, suggesting that peripheral synovitis in PsA belongs to the SpA concept.

The anti-inflammatory action of methotrexate is not mediated by lymphocyte apoptosis, but by the suppression of activation and adhesion molecules

Low-dose methotrexate (MTX) is an established and highly effective treatment for severe psoriasis and rheumatoid arthritis; however, its mechanism of action remains unclear. We investigated the effects of low-dose MTX on antigen-stimulated peripheral blood mononuclear cells and explored through which cellular pathways these effects are mediated. We show that MTX caused a dose-dependent suppression of T cell activation and adhesion molecule expression, and this was not due to lymphocyte apoptosis. The suppression of intercellular adhesion molecule (ICAM)-1 was adenosine and folate-dependent, while MTX suppression of the skin-homing cutaneous lymphocyte-associated antigen (CLA) was adenosine-independent. The effect of MTX on CLA, but not ICAM-1, required the constant presence of MTX in cultures. Thus, the suppression of T cell activation and T cell adhesion molecule expression, rather than apoptosis, mediated in part by adenosine or polyglutamated MTX or both, are important mechanisms in the anti-inflammatory action of MTX.

Effects of oral prednisolone on biomarkers in synovial tissue and clinical improvement in rheumatoid arthritis

OBJECTIVE

To create greater understanding of the changes in synovial tissue parameters that occur in conjunction with clinical response by using an effective therapy, in order to facilitate the planning of future studies with therapeutic agents for rheumatoid arthritis (RA).

METHODS

Twenty-one patients with active RA were randomized to receive either oral prednisolone (n = 10) or placebo (n = 11) for 2 weeks. In all patients, synovial tissue biopsy specimens were obtained by arthroscopy directly before treatment and after 14 days of treatment. Immunohistochemical analysis was performed to characterize the cell infiltrate and vascularity. Stained tissue sections were analyzed by digital imaging. Statistical analysis was performed using an analysis of covariance model.

RESULTS

After treatment, the mean Disease Activity Score in 28 joints (DAS28) was 2.0 units lower (95% confidence interval [95% CI] 1.0-3.0) in patients who received prednisolone than in those who received placebo. In the prednisolone group, the mean (+/-SD) DAS28 decreased from 6.27 +/- 0.95 to 4.11 +/- 1.43 after therapy; minimal change was observed in the placebo group. For macrophages, the estimated effect of prednisolone was large. Patients receiving active treatment had fewer (mean 628 cells/mm(2) [95% CI 328-927]) macrophages after therapy compared with those receiving placebo. A reduction in the total number of CD68+ macrophages, from 1,038 +/- 283 cells/mm(2) before treatment to 533 +/- 248 cells/mm(2) after treatment, was observed in the prednisolone group. There were clear trends toward decreased infiltration by T cells, plasma cells, and fibroblast-like synoviocytes after active treatment. We observed a trend toward a reduction in alphavbeta3+ newly formed blood vessels and expression of vascular growth factors after prednisolone therapy.

CONCLUSION

Prednisolone therapy in RA is associated with a marked reduction in macrophage infiltration in synovial tissue, suggesting that synovial macrophage numbers could be used as a biomarker for clinical efficacy.

Synovial tissue interleukin-18 expression and the response to treatment in patients with inflammatory arthritis

OBJECTIVE

To measure synovial tissue interleukin-18 (IL-18) expression in patients with inflammatory arthritis, and to identify associations with serum levels, disease activity, and response to treatment.

METHODS

Synovial tissue biopsies and serum samples were obtained from patients with early, active, rheumatoid arthritis (RA) (n = 12), undifferentiated seronegative arthritis (SnA) (n = 9), psoriatic arthritis (PsA) (n = 5), and reactive arthritis (ReA) (n = 2) before and one year after introduction of disease modifying antirheumatic drug (DMARD) treatment. Osteoarthritis (OA) tissues were compared. Tissue IL-18 expression was determined after immunohistochemical staining using a semiquantitative scale. Serum IL-18 was measured by enzyme linked immunosorbent assay.

RESULTS

Before treatment was started, tissue IL-18 expression was increased in each diagnostic group compared with OA (p<0.05). Tissue IL-18 expression was correlated with serum C reactive protein levels (r = 0.53, p = 0.003) but not with serum IL-18. After DMARD treatment, 12 patients (five RA, four SnA, three PsA) were re-evaluated. Decreases in tissue IL-18 expression were observed in eight, although the trend did not reach significance (p = 0.068). Changes in tissue IL-18 expression were correlated with changes in serum IL-18 (r = 0.62, p = 0.041) and C reactive protein (r = 0.72, p = 0.009).

CONCLUSIONS

Synovial tissue IL-18 expression was correlated with disease activity in inflammatory arthritis. After treatment, tissue levels changed in parallel with changes in serum IL-18 and with changes in the acute phase response. These observations support a role for IL-18 in the pathophysiology of inflammatory arthritis.

Synovial tissue macrophages: a sensitive biomarker for response to treatment in patients with rheumatoid arthritis

BACKGROUND

Previous work identified synovial sublining macrophage numbers as a potential biomarker for clinical efficacy in rheumatoid arthritis.

OBJECTIVE

To investigate the association between changes in infiltration of synovial macrophages and clinical improvement after antirheumatic treatment.

METHODS

88 patients who participated in various clinical trials were studied. All patients underwent serial arthroscopy before initiation of treatment and after different time intervals. Immunohistochemical and digital image analysis were performed according to standardised procedures to detect changes in CD68+ synovial sublining macrophages in relationship to changes in the 28 joint count Disease Activity Score (DAS28). Statistical analysis was performed using one way analysis of variance, the independent samples t test, linear regression, and the standardised response mean (SRM).

RESULTS

For good, moderate, and non-responders, according to the DAS28 response criteria, there was a significant difference in the change in sublining macrophages (mean (SEM) cells/mm(2) -643 (124), -270 (64), and -95 (60), respectively; p<0.0003). There was a significant correlation between the change in the number of macrophages and the change in DAS28 (Pearson correlation 0.874, p<0.01). The change in sublining macrophages explained 76% of the variation in the change in DAS28 (p<0.02). The sensitivity to change of the biomarker was high in patients treated actively (SRM >0.8), whereas the ability to detect changes in placebo treated patients was weak (SRM <0.3).

CONCLUSION

The results suggest that changes in synovial sublining macrophages can be used to predict possible efficacy of antirheumatic treatment.

Reduction of synovial sublining layer inflammation and proinflammatory cytokine expression in psoriatic arthritis treated with methotrexate

OBJECTIVE

Methotrexate is one of the most commonly used disease-modifying antirheumatic drugs in the management of psoriatic arthritis (PsA). Despite the differences between the inflammation in PsA and rheumatoid arthritis (RA), the effects of methotrexate on the synovium have been described solely in RA. In this study, we sought to determine the effects of methotrexate on the inflammatory infiltrate and on cytokine and metalloproteinase gene expression in the synovium of PsA patients.

METHODS

Ten patients with PsA (median duration 18 months) underwent arthroscopy and synovial biopsy of an inflamed knee before and after clinical improvement induced by methotrexate. Immunohistologic analysis was performed using antibodies to CD3, CD4, CD8, CD68, factor VIII, vascular cell adhesion molecule, E-selectin, and intercellular adhesion molecule (ICAM). Matrix metalloproteinase 3 (MMP-3) and tissue inhibitor of metalloproteinases 1 (TIMP-1) messenger RNA (mRNA) were quantified by competitive reverse transcription-polymerase chain reaction (RT-PCR). Interleukin-1alpha (IL-1alpha), IL-1beta, IL-2, IL-4, IL-5, IL-8, IL-10, IL-12p35, IL-12p40, IL-15, interferon-gamma (IFNgamma), and tumor necrosis factor alpha (TNFalpha) mRNA expression was quantified by real-time PCR.

RESULTS

Patients received a median methotrexate dosage of 13.75 mg/week (range 7.5-15) for a median of 11.5 months (range 7-14 months). The Ritchie Articular Index, swollen joint count, and Disease Activity Score were significantly reduced. There was a decrease in all immunohistologic staining, although this was statistically significant only for CD3, CD4, CD8, CD68, E-selectin, and ICAM. Despite clinical improvement in all patients, there was a residual T cell infiltrate in all synovial biopsy tissues. The synovial lining layer thickness, but not hypervascularity, was significantly reduced. There was also a significant reduction in MMP-3, but not TIMP-1, expression. Before treatment, PsA synovium was characterized by a predominant expression of the proinflammatory cytokines IL-15, IFNgamma, IL-1beta, and TNFalpha and the antiinflammatory cytokine IL-10. Methotrexate reduced synovial IL-1alpha, IL-1beta, IL-8, IL-10, IL-15, IFNgamma, and TNFalpha mRNA expression, but the effect was significant only for IL-8.

CONCLUSION

Methotrexate produced a clinical response in PsA by reducing, but not abolishing, the inflammatory infiltrate, adhesion molecule expression, and MMP-3 and proinflammatory cytokine gene expression, particularly IL-8, in the synovium. Methotrexate did not reduce hypervascularity, which is a prominent differentiating feature of PsA synovium.

Early effects of tumour necrosis factor alpha blockade on skin and synovial tissue in patients with active psoriasis and psoriatic arthritis

BACKGROUND

Tumour necrosis factor alpha (TNFalpha) blockade using infliximab, a chimeric anti-TNFalpha antibody, is an effective treatment for both psoriasis and psoriatic arthritis (PsA).

OBJECTIVE

To analyse the early effects of infliximab treatment on serial skin and synovial tissue biopsy samples.

METHODS

Twelve patients with both active psoriasis and PsA received a single infusion of either infliximab (3 mg/kg) (n = 6) or placebo (n = 6) intravenously. Synovial tissue and lesional skin biopsy specimens were obtained at baseline and 48 hours after treatment. Immunohistochemical analysis was performed to analyse the inflammatory infiltrate. In situ detection of apoptotic cells was performed by TUNEL assay and by immunohistochemical staining with anti-caspase-3 antibodies. Stained tissue sections were evaluated by digital image analysis.

RESULTS

A significant reduction in mean (SEM) T cell numbers was found in both lesional epidermis (baseline 37 (11) cells/mm, 48 hours 26 (11), p = 0.028) and synovial tissue (67 (56) cells/mm(2)v 32 (30), p = 0.043) after infliximab treatment, but not after placebo treatment (epidermis 18 (8) v 43 (20), NS; synovium 110 (62) v 46 (21), NS). Similarly, the number of macrophages in the synovial sublining was significantly reduced after anti-TNFalpha treatment (100 (73) v 10 (8), p = 0.043). The changes in cell numbers could not be explained by induction of apoptosis at the site of inflammation.

CONCLUSIONS

The effects of anti-TNFalpha therapy in psoriasis and psoriatic arthritis may be explained by decreased cell infiltration in lesional skin and inflamed synovial tissue early after initiation of treatment.

IL-15 and the initiation of cell contact-dependent synovial fibroblast-T lymphocyte cross-talk in rheumatoid arthritis: effect of methotrexate

To characterize the molecules responsible for synovial fibroblast-T lymphocyte (TL) cross-talk in rheumatoid arthritis (RA), synovial fibroblasts from patients with established RA (RASFibs) were cocultured with TLs from peripheral blood of early RA patients (RAPBTL). TLs from peripheral blood of healthy controls and from synovial fluid of RA served as controls. Adhesion molecules and cytokines were determined by flow cytometry, ELISA, and real-time PCR. RAPBTL (n = 20) induced an up-regulation of ICAM-1, intracellular IL-8, IL-6, IL-15, and surface IL-15 in cocultured RASFibs. In turn, RAPBTL showed an up-regulation of TNF-alpha, IFN-gamma, IL-17, CD25, and CD69 expression. Responses seen with TLs from peripheral blood of healthy controls (n = 20) were significantly lower, whereas responses with TLs from synovial fluid of RA (n = 20) were maximal. Blocking Abs to IL-15 and CD54, but not an isotype-control Ab, down-regulated the increased TL cytokine and activation marker expression. Abs to CD69, CD11a, IL-17, TNF-alpha, and IFN-gamma significantly decreased the up-regulation of RASFib cytokine and CD54 expression. Cocultures using 0.4- micro m inserts did not result in up-regulation of surface molecules or cytokines. Methotrexate significantly inhibited RASFib/TL cross-talk signals and decreased adhesion of TL to RASFibs. In summary, RASFib production of IL-15 induces the proinflammatory cytokines TNF-alpha, IFN-gamma, and IL-17 in cocultured TLs through a cell contact-dependent mechanism. In turn, these cytokines stimulate the expression of IL-15, IL-8, and IL-6 in RASFibs, thereby creating a feedback loop that favors persistent synovial inflammation. Methotrexate seems to disrupt this loop by decreasing cell adhesion.

Methotrexate markedly reduces the expression of vascular E-selectin, cutaneous lymphocyte-associated antigen and the numbers of mononuclear leucocytes in psoriatic skin

A positive correlation between disease severity and the frequency of cutaneous lymphocyte-associated antigen (CLA)-positive T cells in the blood of untreated patients with psoriasis has been previously observed. A dose-dependent inverse relationship between disease severity and the frequency of circulating CLA(+) T cells in psoriasis patients on methotrexate (MTX) treatment is reported. Circulating T cells from a patient with psoriasis were monitored for CLA expression on a daily basis for 5 weeks. A decrease in the intensity and frequency of CLA(+) mononuclear leucocytes was consistently observed in the blood during the first 3-4 days after each MTX intake, but the CLA expression increased thereafter until the next weekly dose was taken. The MTX treatment of this patient was then discontinued for 16 days, and a marked subjective exacerbation was reported within 9 days, which was confirmed objectively (laser Doppler perfusion imaging) after 11 and 16 days. Biopsies taken 4 days after the last MTX intake showed only a few mononuclear leucocytes in lesional skin, but the exacerbation coincided with a marked increase in CLA expression by mononuclear blood leucocytes, followed by an increase in endothelial E-selectin and a striking influx of CLA(+) mononuclear cells into lesional skin. Conversely, a clinical improvement after the patient resumed the MTX treatment was associated with reduction in CLA expression by mononuclear cells in the blood, downregulation of endothelial E-selectin and an approximate threefold decrease in mononuclear leucocyte infiltration of lesional skin. No MTX-associated changes were detected in the expression of very late antigen-4, vascular cell-adhesion molecule-1 nor the late activation marker CD25. It is concluded that MTX decreases the expression of CLA and E-selectin and that this may be a major mechanism for the therapeutic effect of MTX on psoriatic skin lesions.

Successful treatment of rheumatoid arthritis is associated with a reduction in serum sE-selectin and thrombomodulin level

The aim of this study was to investigate the changes in serum levels of endothelial cell injury markers, soluble (s) E-selectin and thrombomodulin (TM), in patients with rheumatoid arthritis (RA) before and after antirheumatic drug treatment and to assess the relationship between these changes and clinical responses to the drug treatment. Eleven patients with RA having active arthritis and 12 healthy volunteers were enrolled in the study. They were monitored by clinical and laboratory parameters while receiving a combination of methotrexate, hydroxychloroquine and sulphasalazine. Pre- and post-treatment clinical and laboratory parameters, including sE-selectin and sTM levels, were measured. The ages of the patients were comparable with those of the control groups. Significant improvements were detected in erythrocyte sedimentation rate, C-reactive protein, hemoglobin, morning stiffness, patients' global assessment, physicians' global assessment, number of tender joints and number of swollen joints improved at the end of the therapy (for each parameter p < 0.05). Significant improvements were detected in clinical and laboratory parameters. In the patient group there were significant decreases in the levels of sTM and sE-selectin after treatment (p < 0.05). The patient group had significantly higher sTM and sE-selectin levels than the control group at the beginning of the study (p < 0.01), but the difference returned to normal after the treatment (p > 0.05). The sE-selectin and sTM levels significantly correlated with each other, and also with clinical and laboratory findings. Combination treatment successfully treated RA patients. sE-selectin and sTM levels probably reflect disease activity and can be helpful in monitoring disease status and response to therapy.

Methotrexate for ankylosing spondylitis

BACKGROUND

Ankylosing spondylitis (AS) is a chronic inflammatory disease of unknown cause, characterized by sacroiliitis and spondylitis. To date, treatment of AS has been limited to the alleviation of symptoms, mainly using non-steroidal anti-inflammatory drugs (NSAIDs). For patients refractory or intolerant to NSAIDs, the disease modifying antirheumatic drugs (DMARDs) have been used as a second line approach. Methotrexate (MTX) is currently one of the most widely used DMARDs and its efficacy in rheumatoid arthritis (RA) has been confirmed (Suarez-Almazor 2003). There is uncertainty whether MTX works in the treatment of AS.

OBJECTIVES

To evaluate the efficacy and toxicity of methotrexate in the treatment of ankylosing spondylitis.

SEARCH STRATEGY

Relevant randomised and quasi-randomised trials in any language were sought using the following sources: CENTRAL (Cochrane Central Register of Controlled Trials, Issue 2, 2003), MEDLINE (1966 to June Week 4 2003), EMBASE (1980 to 2003 Week 26), CINAHL (1982 to June Week 3 2003) and the reference section of retrieved articles.

SELECTION CRITERIA

We evaluated randomised and quasi-randomised trials examining the efficacy of methotrexate on AS.

DATA COLLECTION AND ANALYSIS

Unblinded trial reports were reviewed independently by two reviewers according to the selection criteria. Disagreements on the inclusion of the studies were resolved, where necessary, by recourse to a third reviewer. The methodological quality of included trials were independently assessed by the same reviewers on randomization, concealment, blindness (participants, care providers and outcome investigators), description of withdrawals and drop-outs and intention-to-treat analysis. The same reviewers independently entered the data extracted from the included trials, using RevMan's double entry facility. In the absence of significant heterogeneity, results were combined using weighted mean difference or standardised mean difference for continuous data, and relative risk for dichotomous data.

MAIN RESULTS

Two trials met the inclusion criteria. Altan 2001compared naproxen plus MTX (7.5 mg/week orally) with naproxen alone and Roychowdhury 2002 compared MTX (10 mg/week orally) with placebo. The duration of the trials were 12 months and 24 weeks, respectively. They assessed different outcomes except for C-reactive protein (CRP). The included trials treated a total of 81 patients and assessed more than 10 outcomes relevant to the review, covering function, pain, peripheral arthritis/enthesitis, morning stiffness, patient and physician global assessment, CRP and erythrocyte sedimentation rate (ESR). No significant difference between intervention groups was found favouring MTX over no MTX. No serious side effect was reported in either trial.

REVIEWERS' CONCLUSIONS

There was no statistically significant benefit of MTX in the examined outcomes for AS patients. High quality, larger sample and longer period of randomized controlled trials (possibly with higher dosage of MTX) are needed to verify the uncertainty about the efficacy and toxicity of MTX for the treatment of AS.

Cytokines, chemokines, and cell adhesion molecules in inflammatory myopathies

The inflammatory myopathies include dermatomyositis (DM), polymyositis (PM), and sporadic inclusion-body myositis (s-IBM). In DM, the main immune effector response appears to be humoral and directed against the microvasculature, whereas in both PM and s-IBM, cytotoxic CD8+ T cells and macrophages invade and eventually destroy nonnecrotic muscle fibers expressing major histocompatibility complex class I. The need for more specific and safer therapies in inflammatory myopathies has prompted researchers to better decipher the molecular events associated with inflammation and muscle fiber loss in these diseases. The complex specific migration of leukocyte subsets to target tissues requires a coordinated series of events, namely activation of leukocytes, adhesion to the vascular endothelium, and migration. Cell adhesion molecules (CAM) and chemokines play a major role in this multistep process. In addition, cytokines by stimulating CAM expression and orchestrating T-cell differentiation also influence the immune response. This review focuses on recent advances in defining the molecular events involved in leukocyte trafficking in inflammatory myopathies. Specific topics include a concise summary of clinical features, pathological findings and immunopathology observed in inflammatory myopathies, background information about cytokines, chemokines and cell adhesion molecules, and the expression of these molecules in inflammatory myopathies.

Are synovial biopsies of diagnostic value?

Synovial tissue is readily accessible by closed needle or arthroscopic biopsy. These techniques provide adequate tissue for most diagnostic requirements. Examination of synovial tissue can assist in the diagnosis of some joint infections, and in several atypical or rare synovial disorders. Histological confirmation is not normally required for diagnosis of the common forms of inflammatory arthritis, including rheumatoid arthritis (RA). In patients with either established or early RA, immunohistological measures of inflammation in synovial tissue are associated with clinical measures of disease activity, may predict the clinical outcome, and change in response to treatment. Surrogate markers of disease activity and outcome that have been identified in synovial tissue include components of the cellular infiltrate, and several mediators of inflammation and matrix degradation. There is evidence that the very early introduction of disease-modifying therapy inhibits progressive structural damage maximally. Clinicians exploiting this 'window of opportunity' therefore require very early indicators of the diagnosis and outcome in patients who present with an undifferentiated inflammatory arthritis. Some immunohistological features have been described that distinguish patients who are likely to develop progressive RA and who might benefit most from early aggressive therapeutic intervention. In this regard, the inclusion of pharmacogenomic and proteomic techniques in the analysis of synovial tissue presents some exciting possibilities for future research.

Tumor necrosis factor alpha blockade reduces the synovial cell infiltrate early after initiation of treatment, but apparently not by induction of apoptosis in synovial tissue

OBJECTIVE

To determine whether treatment with the chimeric anti-tumor necrosis factor alpha antibody infliximab could reduce cellularity by the induction of apoptosis in synovial tissue.

METHODS

Twenty-four rheumatoid arthritis patients with active disease were randomized to receive either infliximab (3 mg/kg) (n = 12) or placebo (n = 12) intravenously. All patients were subjected to arthroscopic synovial biopsy directly before initiation of treatment. A second arthroscopic synovial biopsy of the same index joint was performed 48 hours after the first arthroscopy. After the second arthroscopy, the patients who had initially received placebo were also treated with infliximab in an extension study. A third arthroscopy was performed in all patients on day 28. Immunohistologic analysis was performed to characterize the cell infiltrate. In situ detection of apoptotic cells was performed by TUNEL assay and electron microscopy.

RESULTS

At 48 hours after initiation of infliximab treatment, there was a significant reduction in the number of intimal macrophages; this was not observed in the placebo group. The number of sublining macrophages, T cells, and plasma cells also tended to be decreased in infliximab-treated patients, but not in the placebo group. Of interest, we did not detect any increase in the number of apoptotic cells after infliximab treatment.

CONCLUSION

Infliximab therapy may reduce the number of inflammatory cells in rheumatoid synovial tissue as soon as 48 hours after initiation of treatment, but apparently not by induction of apoptosis. Conceivably, decreased cell infiltration primarily results from early inhibition of cell migration.

Methotrexate inhibits proliferation and regulation of the expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 by cultured human umbilical vein endothelial cells

BACKGROUND

The mechanism by which a low dose of methotrexate (MTX) works to treat psoriasis is not clear. The overexpression of cell adhesion molecules on dermal vessels is important in the pathogenesis of psoriasis and is probably induced by upregulation of tumour necrosis factor (TNF)-alpha.

OBJECTIVES

To determine the effects of MTX at concentrations comparable with in vivo levels after the administration of low-dose MTX to human umbilical vein endothelial cells (HUVEC) on the growth and expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1).

METHODS

Cell proliferation assay, immunostaining, immunoblotting, cell enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction (RT-PCR) were performed to examine the effects of MTX on HUVEC.

RESULTS

MTX inhibited the proliferation of HUVEC at 10-7 mol L-1 and 10-6 mol L-1 without showing cytotoxic effects. It also inhibited TNF-alpha-induced ICAM-1 and VCAM-1 expression by HUVEC at 10-6 mol L-1. The inhibitory effect of MTX was more pronounced on ICAM-1 expression than on VCAM-1 expression. RT-PCR analysis revealed that TNF-alpha-induced ICAM-1 gene expression was strongly downregulated by MTX.

CONCLUSIONS

Low-dose MTX may act on psoriasis by suppressing the TNF-alpha-induced expression of ICAM-1 and VCAM-1 by vascular endothelial cells. Inhibition of neovascularization may be another mechanism of action of MTX.

Increased perivascular synovial membrane expression of myeloid-related proteins in psoriatic arthritis

OBJECTIVE

To analyze S-100 protein expression, in the form of myeloid-related protein 8 (MRP8), MRP14, and the heterodimer MRP8/MRP14, in psoriatic arthritis (PsA) patients compared with rheumatoid arthritis (RA) and spondylarthropathy (SpA) patients, and to determine the effect of methotrexate (MTX) on the MRP antigen expression in PsA patients.

METHODS

Serum, synovial fluid (SF), and synovium (taken at arthroscopy) samples were obtained from PsA (before and after MTX treatment), RA, and SpA patients. Concentrations of MRP8/MRP14 in serum and SF were measured by enzyme-linked immunosorbent assay. Expression of MRP8, MRP14, and MRP8/MRP14 in synovium was determined by immunohistochemistry.

RESULTS

MRP8, MRP14, and MRP8/MRP14 levels were increased in serum, SF, and synovium from PsA, RA, and SpA patients. In all 3 groups, paired samples of serum and SF showed significantly higher MRP8/MRP14 levels in SF (mean +/- SD 15310 +/- 16999 ng/ml [median 11400]) than in serum (908 +/- 679 ng/ml [median 695]) (P = 0.0001). MRP8/MRP14 levels in serum correlated with systemic parameters of disease activity (erythrocyte sedimentation rate [ESR] r = 0.55, P = 0.005; C-reactive protein [CRP] level r = 0.55, P = 0.005), whereas levels in SF correlated with local parameters of disease activity (white blood cell count r = 0.45, P = 0.01; acute-phase serum amyloid A level r = 0.32, P = 0.03). MRP expression was significantly higher in the synovial sublining layer (SLL) of PsA patients compared with RA and SpA patients. MRP antigens were predominantly expressed in perivascular areas of the SLL in PsA patients. Following MTX treatment, MRP expression in serum and synovium from PsA patients was significantly reduced. Serum levels of MRP were more sensitive to the effects of MTX than were the ESR, CRP, or clinical joint scores.

CONCLUSION

MRP levels in serum and SF correlate with local and systemic inflammation and are equally increased in PsA, RA, and SpA patients. In contrast, MRP8, MRP14, and MRP8/MRP14 expression in the SLL of PsA patients is increased, particularly in perivascular regions, compared with that in RA and SpA patients, suggesting a central role of MRP proteins in transendothelial migration of leukocytes in PsA. Moreover, MRP expression is reduced following MTX treatment. MRP proteins may represent a novel therapeutic target in inflammatory arthritis.

Adhesion molecules in gonarthrosis and knee prosthesis aseptic loosening follow-up: possible therapeutic implications

The involvement of the synovium is common in phlogistic processes of various joint diseases. Apart from synoviocytes and the other cells in the synovial tissue, circulating cells recruited from peripheral blood also participate in the phlogistic process. The increased expression of adhesion molecules on both circulating and endothelial cell surface may further this recruitment. We studied 15 patients affected by serious gonarthrosis requiring a prosthetic implant (GPI) and 7 with knee prosthesis aseptic loosening (KPL) to evaluate adhesion molecule expression and phlogistic infiltration in the synovium using immunohistochemistry and microscopic analysis. As control we studied 10 subjects affected by degenerative meniscopathies undergoing a selective arthroscopic surgical meniscectomy. Analysis with Kruskal-Wallis test showed no statistical significant differences in the expression of CD54, CD11a, CD11b and CD18 in three groups examined. The model of variance analysis (Friedman test), showed that CD54 expression is greater in patients with GPI and KPL in comparison with the other molecules. Adhesion molecules and their functions are important in arthropathies not only because their evaluation can allow us to identify the degree of inflammation and to predict its evolution, but also because pharmacological control of their expression could have important therapeutic implications.

Pharmacokinetics and pharmacodynamics of methotrexate in non-neoplastic diseases

Low dose pulse methotrexate (LDMTX) therapy has become effective in the treatment of autoimmune and lymphoproliferative diseases. The pharmacokinetics of LDMTX is individually highly variable, resulting in a different systemic exposure to the drug and a variable therapeutic/toxic effect in patients. The improvements and exacerbations of disease activity in relation to the introductions and discontinuations of LDMTX therapy suggest the possible immunosuppresive and anti-inflammatory properties of the drug. Because of a strong correlation between the drug pharmacokinetics and the therapeutic outcomes (pharmacodynamics), it seems to be possible to individualise the LDMTX therapy according to the results of pharmacokinetic/pharmacodynamic analysis. In the case of psoriasis, pharmacokinetic/pharmacodynamic analysis in our local study revealed a highly significant inverse relationship between PASI (expressed as a percent of the initial value) and a steady-state AUC(MTX) (area under the curve of methotrexate plasma concentrations; r(8) = -0.65, p < 0.001). The considerable inter-individual variability and low intra-individual variability in MTX pharmacokinetics, supports a role for therapeutic monitoring and dose individualisation at the start of pharmacotherapy. The results of this study suggest that a steady-state AUC(MTX) value of 700 nmol x h/L and higher are associated with a significantly better success rate of antipsoriatic therapy than lower values. The preliminary results in our follow-up study suggest the statistically higher incidence of unwanted effects depending on maximum plasma concentration of the drug. Moreover, statistically significant correlation was found between the toxic effects and exposure to the drug regarding methotrexate plasma concentrations and intracellular storage in erythrocytes. However, the data are still in the process of being completed and are not yet published.

Intra-arterial catheter directed therapy for severe graft-versus-host disease

Graft-versus-host disease (GVHD) is a major complication of allogeneic bone marrow transplantation (BMT), resulting in death in the majority of steroid-resistant patients. We assessed the efficacy of regional intra-arterial treatment in patients with resistant hepatic and/or gastrointestinal (GI) GVHD. In total, 15 patients with steroid resistant grade 3-4 hepatic (n = 4), gastrointestinal (GI) (n = 8) GVHD or both (n = 3) were given intra-arterial treatment. Patients with hepatic GVHD received methotrexate and methylprednisolone into the hepatic artery. Patients with GI GVHD were treated with infusions of methylprednisolone into the superior and inferior mesenteric arteries. Two patients with pronounced upper GI symptoms also received upper GI treatment. In total, 25 procedures were carried out (range 1-3 per patient). Hepatic response was observed in four out of seven (57%) patients with hepatic GVHD, three (43%) featuring good response. Complete responses were observed in nine (82%) GI GVHD patients, with median time to initial and complete response of 3 d (range 1-7) and 15.8 d (range 4-33) respectively. Regional treatment of severe GVHD with intra-arterial treatment appears to be effective and safe. GI treatment maybe more effective than intrahepatic treatment. Early administration of isolated intra-arterial therapy in high-risk patients may further improve the outcome and reduce untoward effects of systemic immunosuppressive treatment.

Mediators of inflammation are down-regulated while apoptosis is up-regulated in rheumatoid arthritis synovial tissue by polymerized collagen

The aim of the study was to determine whether collagen-polyvinylpyrrolidone (collagen-PVP) modifies some proinflammatory responses in synovium cultures from rheumatoid arthritis (RA) patients. Synovium from 10 RA patients were cultured with or without 1% collagen-PVP. Tissues on the 3rd, 5th and 7th culture day were sectioned and stained by the Herovici technique. Total collagen and type I/III collagen ratios were evaluated by the Woessner micromethod and by interrupted gel electrophoresis, respectively. Collagenolytic activity was assessed by degradation of [3H]-collagen in supernatants. TIMP-1, IL-1beta and TNF-alpha were determined in supernatants by ELISA, and the results were normalized by DNA concentration. IL-1beta, TNF-alpha, IL-6, IL-8, MMP-1, TIMP-1, Cox-1, VCAM-1, ICAM-1 and Fas/APO95 expression was evaluated by immunohistochemistry. Apoptosis was detected by TUNEL technique. The histological analysis and electrophoresis revealed a 1.7-fold increase of type III collagen in a time-dependent fashion in collagen-PVP-treated cultures. Proinflammatory cytokines (IL-1beta: 58 +/- 9 versus 22 +/- 10; TNF-alpha: 41 +/- 6 versus 11 +/- 3; IL-8: 59 +/- 12 versus 29 +/- 9; treated versus untreated), adhesion molecule (ICAM-1: 57 +/- 11 versus 29 +/- 15; VCAM-1: 49 +/- 7 versus 21 +/- 13; treated versus untreated) as well as Cox-1 (59 +/- 10 versus 20 +/- 3) expression was down-regulated in RA synovium treated. Meanwhile, TIMP-1 (36 +/- 7 versus 57 +/- 11) and Fas expression (20 +/- 10 versus 55 +/- 13) and apoptosis (14 +/- 3 versus 55 +/- 5) were up-regulated in treated cultures compared with controls. In supernatants, the collagenolytic activity, as well as IL-1beta and TNF-alpha, levels were all down-regulated in treated cultures (two, three, fourfold, respectively). The addition of collagen-PVP to synovium-induced down-modulation of some inflammatory parameters and an increase in apoptosis of synovial cells. Perhaps this mechanism could contribute to inhibit outgrowth of pannus formation and to down-regulate inflammation of joints in patients with RA.

Co-stimulatory and adhesion molecules of dendritic cells in rheumatoid arthritis

Dendritic cells (DCs) in the rheumatoid arthritis (RA) joint mediate the immunopathological process and act as a potent antigen presenting cell. We compared the expression of co-stimulatory and adhesion molecules on DCs in RA patients versus controls with traumatic joint lesions and evaluated the correlation between the immunophenotypical presentation of DCs and the clinical status of the disease. Samples of peripheral venous blood, synovial fluid (SF) and synovial tissue (ST) were obtained from 10 patients with RA at the time of hip or knee replacement and from 9 control patients with knee arthroscopy for traumatic lesions. Clinical status was appreciated using the DAS28 score. Blood, SF and dissociated ST cell populations were separated by centrifugation and analyzed by flow cytometry. Cells phenotypes were identified using three-color flow cytometry analysis for the following receptors HLA-DR, CD80, CD83, CD86, CD11c, CD18, CD54, CD58, CD3, CD4, CD8, CD19, CD20, CD14, CD16, CD56. HLA-DR molecules, co-stimulatory receptors CD80, CD86, CD83 and adhesion molecules CD18, CD11c, CD54, CD58, were analyzed by two-color immunofluorescence microscopy on ST serial sections. In patients with active RA (DAS28>5.1) we found a highly differentiated subpopulation of DCs in the ST and SF that expressed an activated phenotype (HLA-DR, CD86+, CD80+, CD83+, CD11c+, CD54+, CD58+). No differences were found between circulating DCs from RA patients and control patients. Our data suggest an interrelationship between clinical outcome and the immunophenotypical presentation of DCs. Clinical active RA (DAS28>5.1) is associated with high incidence of activated DCs population in the ST and SF as demonstrated by expression of adhesion and co-stimulatory molecules.

The pathogenesis of rheumatoid arthritis: a guide to therapy

The cause of rheumatoid arthritis (RA) is unknown; however, extensive research has yielded great insight into its pathogenesis. Lymphocytes play a significant role, but a lesser role in the perpetuation of late disease. The rheumatoid synovium is composed primarily of fibroblasts and monocytes that produce inflammatory cytokines, of which interleukin-1 and tumor necrosis factor are of key importance. Potential regulatory mechanisms balancing the effects of these cytokines are inadequate to prevent joint damage and subsequent disability. These cytokines seem responsible for stimulating destructive processes in the joint via induction of prostaglandins, angiogenesis, chemokines, adhesion molecules, osteoclastogenesis, and matrix metalloproteinases. This review discusses recent research findings in the immunopathogenesis of RA with respect to potential targets for therapy.

Inhibition of LFA-1/ICAM-1 and VLA-4/VCAM-1 as a therapeutic approach to inflammation and autoimmune diseases

This review focuses on providing insights into the structural basis and clinical relevance of LFA-1 and VLA-4 inhibition by peptides and small molecules as adhesion-based therapeutic strategies for inflammation and autoimmune diseases. Interactions of cell adhesion molecules (CAM) play central roles in mediating immune and inflammatory responses. Leukocyte function-associated antigen (LFA-1, alpha(L)beta(2), and CD11a/CD18) and very late antigen (VLA-4, alpha(4)beta(1), and CD49d/CD29) are members of integrin-type CAM that are predominantly involved in leukocyte trafficking and extravasation. LFA-1 is exclusively expressed on leukocytes and interacts with its ligands ICAM-1, -2, and -3 to promote a variety of homotypic and heterotypic cell adhesion events required for normal and pathologic functions of the immune systems. VLA-4 is expressed mainly on lymphocyte, monocytes, and eosinophils, but is not found on neutrophils. VLA-4 interacts with its ligands VCAM-1 and fibronectin (FN) CS1 during chronic inflammatory diseases, such as rheumatoid arthritis, asthma, psoriasis, transplant-rejection, and allergy. Blockade of LFA-1 and VLA-4 interactions with their ligands is a potential target for immunosuppression. LFA-1 and VLA-4 antagonists (antibodies, peptides, and small molecules) are being developed for controlling inflammation and autoimmune diseases. The therapeutic intervention of mostly mAb-based has been extensively studied. However, due to the challenging relative efficacy/safety ratio of mAb-based therapy application, especially in terms of systemic administration and immunogenic potential, strategic alternatives in the forms of peptide, peptide mimetic inhibitors, and small molecule non-peptide antagonists are being sought. Linear and cyclic peptides derived from the sequences of LFA-1, ICAM-1, ICAM-2, VCAM-1, and FN C1 have been shown to have inhibitory effects in vitro and in vivo. Finally, understanding the mechanism of LFA-1 and VLA-4 binding to their ligands has become a fundamental basis in developing therapeutic agents for inflammation and autoimmune diseases.

Serum matrix metalloproteinases and tissue inhibitors of metalloproteinases in different histological variants of rheumatoid synovitis

OBJECTIVE

Rheumatoid synovitis is characterized by an invasive and tissue-destructive infiltrate of lymphocytes, macrophages and synoviocytes. Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) produced by these cells are important in the remodelling of the articular tissues in rheumatoid arthritis (RA). The aim of this study was to explore whether the serum concentrations of MMPs and their inhibitors were correlated with the histological appearance of the disease.

METHODS

Tissue and serum samples were obtained from 37 patients with clinically active RA and 30 with osteoarthritis (OA). Morphological analysis allowed the division of RA synovial specimens into two distinct types. In 22 samples only diffuse infiltrates of mononuclear cells without further microanatomical organization were found. In 15 specimens we observed lymphocytic conglomerates with germinal centre-like structures. Serum concentrations of interstitial collagenase (MMP-1), stromelysin-1 (MMP-3), gelatinase B (MMP-9), TIMP-1 and TIMP-2 were measured with an ELISA technique.

RESULTS

Unique serum profiles of MMPs and TIMPs were identified in each of the two histological types of RA synovitis. The serum concentrations of MMP-1, MMP-3 and MMP-9 were higher in RA patients than in OA patients used as a control group (P<0.001 for all comparisons). These three MMPs dominated in the serum of RA patients with follicular synovitis compared with those with diffuse synovitis (P<0.05, P<0.01 and P<0.001 respectively). The analysis of the serum concentrations of TIMP-1 and TIMP-2 showed that their levels were also elevated in RA patients compared with OA patients (P<0.001 and P<0.01 respectively). Only TIMP-1 was found in a significantly higher concentration in the serum of RA patients with follicular synovitis than in those with diffuse synovitis (P<0.05). The serum concentrations of MMPs and TIMP-1 clearly identified patients with two different histological types of rheumatoid synovitis and with OA. Additionally, the analysis of clinical data showed that the rheumatoid disease in patients with follicular synovitis seemed to be more active than in those with diffuse synovitis.

CONCLUSION

The morphological appearance of rheumatoid synovitis and the serum MMP and TIMP-1 profile were correlated with the clinical activity of the disease, confirming the heterogeneity of RA. These associations also suggest that patients with different histological forms of RA might require different treatment regimens.

Association of clinical, radiological and synovial immunopathological responses to anti-rheumatic treatment in rheumatoid arthritis

OBJECTIVES

To compare immunohistochemical scoring with clinical scoring and radiology for the assessment of rheumatoid arthritis (RA) disease activity, synovial tissue (ST) biopsied arthroscopically was assessed from 18 patients before and after commencement of disease-modifying anti-rheumatic drug (DMARD) therapy.

METHODS

Lymphocytes, macrophages, differentiated dendritic cells (DC), vascularity, tumour necrosis factor (TNF) alpha and interleukin-1beta levels were scored. Clinical status was scored using the American College of Rheumatology (ACR) core set and serial radiographs were scored using the Larsen and Sharp methods. Histopathological evidence of activity included infiltration by lymphocytes, DC, macrophages, tissue vascularity, and expression of lining and sublining TNFalpha. These indices co-varied across the set of ST biopsies and were combined as a synovial activity score for each biopsy.

RESULTS

The change in synovial activity with treatment correlated with the ACR clinical response and with decreased radiological progression by the Larsen score. The ACR response to DMARD therapy, the change in synovial activity score and the slowing of radiological progression were each greatest in patients with high initial synovial vascularity.

CONCLUSIONS

The data demonstrate an association between clinical, radiological and synovial immunopathological responses to anti-rheumatic treatment in RA. High ST vascularity may predict favourable clinical and radiological responses to treatment.

Successful treatment of rheumatoid arthritis is associated with a reduction in synovial membrane cytokines and cell adhesion molecule expression

OBJECTIVE

To investigate the change in synovial membrane cytokine content and cell adhesion molecule expression in sequential biopsies from the same knee joint of patients with rheumatoid arthritis, before and following anti-rheumatic drug treatment and to assess the relationship of these changes with clinical responses to the drug treatment.

METHODS

A selected group of patients with rheumatoid arthritis, some of whom had achieved a disease remission based on American College of Rheumatology (ACR) criteria, were included in this study. Sequential synovial biopsies obtained before and throughout the treatment period were studied by immunohistochemical labelling techniques for the cellular content, production of a range of pro- and anti-inflammatory cytokines and the expression of cell adhesion molecules. The staining was quantitated using computer-assisted digital image analysis.

RESULTS

There was a decrease in tumour necrosis factor-alpha (TNFalpha) and interleukin-1beta (IL-1beta) production in the synovial membrane lining and sublining of all patients who responded to treatment. The changes in IL-1 receptor antagonist production were variable. Paradoxically, there was a trend to decreased synovial membrane production of the anti-inflammatory cytokines, IL-10 and transforming growth factor-beta (TGFbeta), while IL-4 was not detectable in any of the synovial membrane biopsies. A significant reduction in the density and total amount of E-selectin expression in the synovial membrane was seen. Similarly, intercellular adhesion molecule-1 (ICAM-1) expression in the lining and sublining was decreased in those patients who had a significant clinical response to drug treatment or attained disease remission. There were no consistent or significant changes seen in the expression of other cell adhesion molecules in the synovial membranes of these patients.

CONCLUSIONS

Successful drug treatment of rheumatoid arthritis patients is characterized at the synovial membrane level by a decrease in TNFalpha, IL-10 and TGFbeta production. Some (E-selectin and ICAM-1) but not all (P-selectin, VCAM-1, PECAM-1) cell adhesion molecules are modulated in patients who respond clinically to drug treatment. E-selectin and ICAM-1 may be important targets for the development of future drug treatments for rheumatoid arthritis.

Isolation and characterization of rheumatoid arthritis synovial fibroblasts from primary culture--primary culture cells markedly differ from fourth-passage cells

To reduce culture artifacts by conventional repeated passaging and long-term culture in vitro, the isolation of synovial fibroblasts (SFB) was attempted from rheumatoid arthritis (RA) synovial membranes by trypsin/collagenase digest, short-term in vitro adherence (7 days), and negative isolation using magnetobead-coupled anti-CD14 monoclonal antibodies. This method yielded highly enriched SFB (85% prolyl-4-hydroxylase+/74% Thy-1/CD90+ cells; <2% contaminating macrophages; <1% leukocytes/endothelial cells) that, in comparison with conventional fourth-passage RA-SFB, showed a markedly different phenotype and significantly lower proliferation rates upon stimulation with platelet-derived growth factor and IL-1beta. This isolation method is simple and reliable, and may yield cells with features closer to the in vivo configuration of RA-SFB by avoiding extended in vitro culture.

Drugs, inflammation and cell adhesion receptors

The cell adhesion receptors that participate in the extravasation and migration of leucocytes towards inflammatory foci mainly include the selectins and different members of the integrin and immunoglobulin superfamilies. These adhesion receptors mediate the sequential steps of leucocyte-endothelial cell interaction and, together with chemoattractant molecules (e.g., chemokines), direct the influx of inflammatory cells and define the characteristics of the cell infiltrate. Many different drugs, including non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, rheumatoid arthritis disease-modifying agents and phosphodiesterase inhibitors, interfere with the expression and/or function of cell adhesion receptors and this effect accounts for, at least in part, their anti-inflammatory activity. In recent years, novel approaches for the modulation of the cell membrane receptors involved in inflammation have been active areas in pharmaceutical research. Upgraded synthetic blocking compounds, chimeric monoclonal antibodies or improved antisense oligonucleotides represent important advances in this field. The proper development of these novel approaches, as well as other alternative strategies, will allow a better and more specific pharmacological modulation of the inflammatory phenomenon.

COX-2 inhibitors vs. NSAIDs in gastrointestinal damage and prevention

Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit production of protective gastric mucosal prostaglandins and also have a direct topical irritant effect. In some patients this results in dyspepsia and development of gastroduodenal erosions and ulceration. The risk of ulcer complications, such as bleeding, perforation and death is increased approximately 4-fold in NSAID users. Patients at high risk of ulcer complications include the elderly, those taking anticoagulants, steroids and aspirin, those with a previous history of peptic ulceration and patients with concomitant serious medical problems. The interaction of NSAIDs with Helicobacter pylori (the major cause of peptic ulceration in non-NSAID users) is controversial and some studies suggest that H. pylori infection may even protect against NSAID-induced ulceration. Selective inhibitors of the inducible cyclooxygenase-2 (COX-2) enzyme spare COX-1 in the gastric mucosa and, hence, do not inhibit production of mucosal prostaglandins. COX-2-selective inhibitors are associated with a significant reduction in gastroduodenal damage compared with traditional NSAIDs. Proton pump inhibitors (PPI) are probably the best agents for healing and prevention of NSAID-induced ulcers. Preliminary studies suggest that COX-2 selective inhibitors, like traditional NSAIDs, may prevent lower gastrointestinal cancer. Further studies are needed but they may be useful in individuals at high risk of certain types of lower gastrointestinal malignancy with increased gastrointestinal tolerability and safety.

Anti-cytokine therapy in chronic destructive arthritis

Tumor necrosis factor (TNF) and interleukin-1 (IL-1) are considered to be master cytokines in chronic, destructive arthritis. Therapeutic approaches in rheumatoid arthritis (RA) patients have so far focused mainly on TNF, which is a major inflammatory mediator in RA and a potent inducer of IL-1; anti-TNF therapy shows great efficacy in RA patients. However, it is not effective in all patients, nor does it fully control the arthritic process in affected joints of good responders. Directed therapy for IL-1, with IL-1 receptor antagonist, mainly reduces erosions and is marginally anti-inflammatory. It is as yet unclear whether the limited effect is akin to the RA process or linked to suboptimal blocking of IL-1. Analysis of cytokine patterns in early synovial biopsies of RA patients reveals a marked heterogeneity, with variable staining of TNF and IL-1 beta, indicative of TNF-independent IL-1 production in at least some patients. Evidence for this pathway emerged from experimental arthritises in rodents, and is summarized in this review. If elements of the models apply to the arthritic process in RA patients, it is necessary to block IL-1 beta in addition to TNF.

Treatment of poor-prognosis early rheumatoid arthritis. A randomized study of treatment with methotrexate, cyclosporin A, and intraarticular corticosteroids compared with sulfasalazine alone

OBJECTIVE

To determine whether a regimen of methotrexate, cyclosporin A, and corticosteroids introduced at onset in poor-prognosis rheumatoid arthritis (RA) can produce a significant improvement in outcome compared with standard monotherapy with sulfasalazine (SSZ).

METHODS

Eighty-two consecutive patients presenting with new, untreated RA of less than 12 months' duration who fulfilled criteria for poor long-term outcome were randomized to receive either combination therapy (n = 40) or SSZ alone (n = 42). The primary outcome measures were remission and American College of Rheumatology (ACR) criteria for 20% improvement at 48 weeks.

RESULTS

After 48 weeks, the numbers of patients who met the ACR criteria for 20% improvement were not significantly different between the two groups (combination 58% versus SSZ 45%), and similar numbers of patients had persisting clinical remission (approximately 10% both groups). During the first 3 months, there were significantly greater reductions in parameters of disease activity in the combination group. By 24 weeks, the swollen and tender joint counts, C-reactive protein levels, and erythrocyte sedimentation rates had fallen significantly in both groups, with a greater improvement in the swollen and tender joint count in the combination group. At 48 weeks, the radiographic damage score had increased by a median of 1 (range 0-42.5) in the combination group and 1.25 (range 0-72.5) in the SSZ group (P = 0.28; although there were significant differences in the scores for the right hand). There were significantly fewer withdrawals due to lack of efficacy in the combination group than in the SSZ group (1 of 40 versus 10 of 42; P = 0.007). In the combination group, dose reduction was needed in 22.5% because of hypertension and in 22.5% because of elevated creatinine levels. Over 48 weeks, serum creatinine increased in both groups, but particularly in the combination arm.

CONCLUSION

In poor-prognosis RA patients, "aggressive" combination therapy led to more rapid disease suppression but did not result in significantly better ACR response or remission rates. This suggests that in poor-prognosis disease, an approach based on identifying patients with poor treatment responses before extra therapy is added ("step-up" approach) may be more appropriate than the use of combination therapy in all patients from the outset.

Modulation of inflammation and metalloproteinase expression in synovial tissue by leflunomide and methotrexate in patients with active rheumatoid arthritis. Findings in a prospective, randomized, double-blind, parallel-design clinical trial in thirty-nine patients at two centers

OBJECTIVE

Leflunomide and methotrexate have proven to be efficacious in reducing joint inflammation and slowing destruction in clinical trials of patients with rheumatoid arthritis (RA). This study was conducted to provide more insight into the mechanism of action of these agents in synovial tissue.

METHODS

In a 2-center, prospective, randomized, double-blind clinical trial, we compared leflunomide (20 mg/day, after a 3-day 100 mg/day loading dose) and methotrexate (increased stepwise to 15 mg/week) treatment in patients with active RA. Paired synovial tissue biopsy samples were obtained by knee arthroscopy at baseline and after 4 months of treatment. Frozen synovial tissue sections were stained for macrophages (CD68), T cells (CD3), adhesion molecules (intercellular adhesion molecule 1 [ICAM-1], vascular cell adhesion molecule 1 [VCAM-1]), cytokines (tumor necrosis factor alpha, interleukin-1beta [IL-1beta]), matrix metalloproteinase 1 (MMP-1), and tissue inhibitor of metalloproteinases 1 (TIMP-1).

RESULTS

Paired synovial tissue sections were available in 35 patients (16 taking leflunomide, 19 taking methotrexate). Both drugs displayed equal clinical efficacy, with 8 leflunomide-treated patients (50%) and 10 methotrexate-treated patients (53%) fulfilling the American College of Rheumatology 20% response criteria. Both compounds showed similar effects on synovial tissue: reduced numbers of macrophages and reduced ICAM-1 and VCAM-1 expression were noted after 4 months of treatment. Both leflunomide- and methotrexate-treated patients exhibited a decreased MMP-1:TIMP-1 ratio in the synovial tissue. In the subset of patients fulfilling the 20% response criteria of the American College of Rheumatology, a more pronounced reduction in the expression of ICAM-1, VCAM-1, IL-1beta, and MMP-1 was found compared with the nonresponders.

CONCLUSION

Leflunomide and methotrexate are clinically efficacious drugs that interfere with mechanisms involved in joint inflammation and destruction of joint integrity.

Inhibition of neutrophil migration soon after initiation of treatment with leflunomide or methotrexate in patients with rheumatoid arthritis: findings in a prospective, randomized, double-blind clinical trial in fifteen patients

OBJECTIVE

Leflunomide is a novel immunomodulating drug that has recently been approved as a disease-modifying antirheumatic drug for the treatment of rheumatoid arthritis (RA). The aim of this study was to determine the relationship between the clinical effects of leflunomide and neutrophil migration.

METHODS

The effects of leflunomide and methotrexate on neutrophil chemotaxis were studied in 15 RA patients who participated in a prospective, randomized, double-blind clinical trial. When possible, neutrophil numbers were counted in synovial fluid (SF) samples at baseline and after 14 days, 4 months, and 1 year of treatment. The chemotactic properties of peripheral blood neutrophils from RA patients treated with either leflunomide or methotrexate were studied by the Boyden chamber technique, using the activators formyl-methionyl-leucyl-phenylalanine (fMLP) and interleukin-8 (IL-8). The in vitro effects of A77 1726, the active metabolite of leflunomide, and methotrexate on peripheral blood neutrophils from 7 healthy control subjects were also investigated.

RESULTS

Both therapy groups exhibited clinical improvement, including rapid reductions in SF neutrophil counts and reduced joint swelling and tenderness. On day 14, 3 of 7 patients who received leflunomide showed no detectable effusions. There was a significant effect on neutrophil chemotaxis (P < 0.001), which was similar for leflunomide and methotrexate. The direct effects on the neutrophils diminished over time. Incubation of peripheral blood neutrophils from healthy controls with A77 1726 confirmed the inhibitory effect on chemotaxis.

CONCLUSION

Leflunomide treatment is beneficial in RA patients. Different mechanisms are operative in various phases of treatment, leading to decreased recruitment of inflammatory cells in the joints.

Quantification of the cell infiltrate in synovial tissue by digital image analysis

OBJECTIVE

The experience with digital image analysis (DIA) in the assessment of synovial inflammation is limited. In this study we compared DIA with two currently applied methods for the evaluation of the synovium.

METHODS

Synovial tissue (ST) specimens were obtained by arthroscopy from knee joints of rheumatoid arthritis (RA) patients with variable disease expression and in control subjects. CD68+ macrophages and CD3+ T-cells were detected by immunohistochemical staining using two different labelling techniques. The labelled ST sections were quantified using three different analysis techniques: manual cell counting (MC), semi-quantitative analysis (SQA) and DIA.

RESULTS

We observed strongly positive correlations between the three methods when examining T-cell infiltration: between MC and SQA: sigma=0.91 (P<0. 0001), between MC and DIA: sigma=0.95 (P<0.0001), and between SQA and DIA: sigma=0.83 (P<0.0001). Similarly, for the analysis of synovial intimal macrophages, positive correlations were noted between MC and SQA (sigma=0.62; P=0.002), MC and DIA (sigma=0.56; P<0.01), and SQA and DIA (sigma=0.79; P<0.0001). Finally, the analysis of synovial sublining macrophages revealed positive correlations between MC and SQA (sigma=0.95; P<0.0001), MC and DIA (sigma=0.64; P=0.001) and SQA and DIA (sigma=0.69; P<0.0001).

CONCLUSION

These three different methods generated similar results. DIA offers the opportunity of a reliable and time-efficient analysis of the synovial infiltrate.

Synovial tissue analysis in rheumatoid arthritis

In rheumatoid arthritis, synovial tissue is easily accessible for systematic analysis. Blind needle biopsy is a simple and safe procedure, but is restricted to smaller tissue samples. Arthroscopic biopsy is also safe but is more complicated as it allows access to most sites in the joint and provides adequate tissue for extensive laboratory investigations. Synovial tissue analysis has been successfully applied to studies of disease mechanisms, response to treatment and prognosis. The immuno-histological features in synovial tissue have consistently reflected disease status. Synovial tissue analysis has been particularly informative in the study of novel therapeutic agents.

Effect of methotrexate on blood purine and pyrimidine levels in patients with rheumatoid arthritis

OBJECTIVE

The mechanism of anti-inflammatory effects of methotrexate (MTX) at low dose may relate to a decrease in availability of the purine precursor or it may depend on accumulation of 5-aminoimidazole-4-carboxamide (AICAR) and the anti-inflammatory nucleoside adenosine. The aim of this study was to evaluate the possible mechanism of action by analysis of changes in blood concentrations of purine and pyrimidine metabolites during MTX treatment.

METHODS

Venous blood samples were collected from rheumatoid arthritis patients before and at different times for up to 7 days after the start of MTX treatment. Whole blood concentrations of adenosine, uridine, hypoxanthine, uric acid and erythrocyte nucleotides were measured by HPLC.

RESULTS

The initial blood adenosine concentration was 0.073 +/- 0.013 microM and no differences were observed during MTX treatment. However, a decrease in uric acid concentration was observed from 205.5+/-13.5 to 160. 9+/-13.5 microM (P<0.05) within 24 h after MTX administration. The hypoxanthine concentration decreased in parallel with uric acid, while the uridine concentration decreased 48 h after MTX administration. No accumulation of AICAR-triphosphate (ZTP) was observed in the erythrocytes.

CONCLUSIONS

MTX decreases circulating purine and pyrimidine concentrations, and their availability for DNA and RNA synthesis, which may affect immune cell proliferation and protein (cytokine) expression. The absence of adenosine concentration changes and lack of ZTP formation is evidence against an AICAR/adenosine mechanism, although localized adenosine concentration changes cannot be excluded.

Effects of anti-rheumatic herbal medicines on cellular adhesion molecules

OBJECTIVE

To test the hypothesis whether herbal medicines ameliorate inflammatory diseases via the modulation of cellular adhesion molecules (CAMs).

METHODS

Human neutrophils, synovial fibroblasts, and endothelial cells were incubated with different concentrations of Tripterygium Wilfordii Hook-f (TWH-f) or Tetrandrine in the presence or absence of interleukin 1 (IL1). The amount of soluble E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cellular adhesion molecule-1 (VCAM-1) secreted by cells were determined by ELISA. The cell surface expression of these three CAMs was detected by flow cytometry.

RESULTS

TWH-f at high concentration (50 ng/ml) has a significant (p<0.05) inhibitory effect on both the secretion and the expression of the cellular adhesion molecules. However, Tetrandrine did not demonstrate the same effects.

CONCLUSIONS

The cellular adhesion molecules of the endothelium and leucocytes may constitute excellent targets for the development of new anti-inflammation medicines. These results indicate that TWH could be a potential therapeutic agent in the treatment of inflammatory diseases.

Monocyte activation in rheumatoid arthritis (RA): increased integrin, Fc gamma and complement receptor expression and the effect of glucocorticoids

The aim of this work was to study the expression of beta 1- and beta 2-integrins, CR1, CD44 and Fc gamma receptors on peripheral blood monocytes in RA. The expression of these receptors was measured by flow cytometry, before and after treatment with low-dose prednisolone. Expression of the same receptors was also measured before and after treatment with metyrapone, a substance that inhibits the synthesis of cortisol in the adrenals. The expression of the beta 2-integrins CD11a, CD11b and CD18, of CD35 (CR1), and of Fc gamma RII and Fc gamma RI (CD32 and CD64) on monocytes was elevated in the RA patients compared with healthy controls, while the expression of the beta 1-integrins (CD29, CD49d, CD49f) was unaffected. A significant correlation between monocyte expression of CD64 and C-reactive protein (CRP), and blood platelet count, respectively, was found in the group of patients with RA. After 4-6 weeks of treatment with low-dose prednisolone, the expression on the monocytes of CD11a, CD11b, CD18, CD35, CD32 and CD64 was normalized. A significant correlation (r = 0.64, P = 0.02) was found between the decrease in expression of CD11b and clinical improvement after prednisolone treatment. Two days of metyrapone treatment, which significantly lowered the serum cortisol levels, elevated the expression of CD35 and CD49f. Priming of peripheral monocytes seems to be one of the mechanisms behind the recruitment of monocytes to the rheumatoid synovium. One reason for the good clinical effects of prednisolone in RA could be a down-regulation of adhesion and phagocytosis receptors on monocytes.