Expression of host defense scavenger receptors in spondylarthropathy

OBJECTIVE

Reactive arthritis (ReA) is postulated to be caused by a defective host defense against gram-negative bacteria. HLA-B27 could play a role in this process, but does not account for the many HLA-B27 negative patients. The objective of this study was to test the expression of 3 macrophage scavenger receptors (SRs) that are responsible for innate immunity against gram-negative bacteria: SR class A type I (SR-AI), SR-AII, and the macrophage receptor with collagenous structure (MARCO). We postulate that defects in such receptors might also contribute to the host risk factors that increase the predisposition to ReA and perhaps other subtypes of spondylarthropathy (SpA).

METHODS

Peripheral blood, synovial fluid, and synovial tissue samples were obtained from patients with recent Salmonella infection, ReA, other SpA, and rheumatoid arthritis (RA). The expression of SRs receptors was assessed by semiquantitative reverse transcriptase-polymerase chain reaction.

RESULTS

Evaluation of the peripheral blood mononuclear cells (PBMC) from 4 patients who were recently infected with Salmonella, showed that PBMC from 2 patients who developed ReA expressed positive levels of MARCO, while PBMC from 2 patients who recovered from infection without sequelae did not. The synovial fluid mononuclear cells (SFMC) from some ReA patients expressed MARCO, but the levels were only moderate. The level of MARCO in the SFMC from the SpA patient group was low. In marked contrast, MARCO expression was high in almost all samples of RA SFMC. These findings also extended to synovial tissues.

CONCLUSION

Expression of the host defense gene MARCO was susceptible to modulation, not only during infections, but also in the inflammatory arthritis conditions RA and SpA. MARCO is a variable to be considered as a candidate factor that might contribute to ReA.

Polyarteritis nodosa mimicking polymyalgia rheumatica

We report a case of polyarteritis nodosa with a clinical presentation mimicking polymyalgia rheumatica, as well as pathological findings of non-giant-cell arteritis on temporal artery biopsy with symptoms of jaw claudication. Although certain clinical syndromes have been attributed to specific types of systemic vasculitis, considerable overlap occurs. Obtaining tissue biopsy in cases of vasculitis is mandatory for diagnosis and classification.

Erosive and non-erosive hand osteoarthritis. Use and limitations of two scoring systems

OBJECTIVE

To assess the evolution and progression of osteoarthritis (OA) in the finger joints using anatomical changes on standard radiographs.

METHODS

Data obtained from 85 patients enrolled in a prospective study were used to evaluate systems to score the morbidity and the progression of the disease over 3 years. Posteroanterior (PA) radiographs of the metacarpophalangeal (MCP) and interphalangeal (IP) joints were obtained at entry and after 3 years. Assessment of the progression of OA over time is based on: (1) the increase in incidence of OA in previously normal joints during the study period, (2) the changes in the OA-associated features (osteophyte growth, loss of joint space, subchondral cysts or sclerosis) in the pathological finger joints (anatomical lesion progression score system), and (3) the recognition of consecutive anatomical phases in the course of 'erosive' OA (anatomical phase progression score system).

RESULTS

Almost 80% of the distal IP and 50% of the proximal IP were affected at study entry. In approximately 40% of the patients, the classical picture of OA of the IP joints was complicated by manifest erosive changes, which were followed by a repair phenomenon in the 'eroded' finger joints. MCP were less affected and showed the non-erosive picture of OA. Numbers of affected DIP, PIP and MCP joints per patient at entry did not differ from those after 3 years of follow-up. Two systems to score the progression of OA (anatomical lesion and anatomical phase progression score system) showed definite progression within 3 years of follow-up, especially in the IP joints. Since changes in both non-erosive and erosive joints were recorded by the anatomical lesion progression system, it was found much more sensitive to change than the anatomical phase progression system which principally recorded the progression through the destructive phases of erosive OA. The results of both progression score systems correlated well.

CONCLUSION

Conventional radiographs can be used to assess the morbidity and progression of hand OA. The existence of non-erosive and erosive forms of OA of the finger joints necessitates the use of two scoring systems: the anatomical lesion progression score system and the anatomical phase progression score system.

Immunomodulatory effects of anti-tumor necrosis factor alpha therapy on synovium in spondylarthropathy: histologic findings in eight patients from an open-label pilot study

OBJECTIVE

To assess the effects of treatment with anti-tumor necrosis factor alpha (anti-TNFalpha) on synovial histology in patients with spondylarthropathy (SpA) in order to confirm the effect on peripheral synovitis and to investigate the immunologic mechanisms involved in anti-TNFalpha therapy.

METHODS

Patients with treatment-resistant SpA were treated with infliximab (5 mg/kg) at weeks 0, 2, and 6 in an open-label pilot study. In 8 patients, synovial biopsy tissues obtained at baseline, week 2, and week 12 were used for histologic and immunohistochemical evaluation.

RESULTS

In all 8 patients (3 with ankylosing spondylitis, 1 with undifferentiated SpA, and 4 with psoriatic arthritis), there was a clear clinical improvement in the peripheral arthritis after anti-TNFalpha therapy. Histologic analysis of the synovial biopsy tissues indicated that the synovial lining layer thickness tended to decrease, with a significant reduction of CD55+ synoviocytes, at week 12. In the sublining layer, vascularity was reduced at week 12, with a decreased endothelial expression of vascular cell adhesion molecule 1 but not intercellular adhesion molecule 1, platelet endothelial cell adhesion molecule 1, and E-selectin. Although at week 2 and week 12, the number of neutrophils and CD68+ macrophages in the sublining layer was decreased, the overall degree of inflammatory infiltration remained unchanged. This could be related to the lymphocyte infiltration since at week 12, only CD4+ cells (but not CD3+, CD45RO+, and CD8+ cells) tended to decrease, while CD20+ lymphocytes and plasma cells were clearly increased.

CONCLUSION

The reduction in lining layer thickness, vascularity, and infiltration with neutrophils and macrophages paralleled the beneficial effect of anti-TNFalpha therapy on peripheral synovitis in 8 patients with different subtypes of SpA. The adhesion molecule expression, T cell infiltration, and, most important, B cell infiltration seemed to contrast with previous observations in RA. Although these preliminary data need to be confirmed in a larger cohort, they suggest distinct immunomodulatory mechanisms of anti-TNFalpha in SpA.

Flow cytometric analysis of the human articular chondrocyte phenotype in vitro

OBJECTIVE

To develop flow cytometry for the study of human articular cartilage cell phenotype and to validate the method on chondrocytes cultured in different in-vitro systems.

METHODS

Chondrocyte phenotype was modulated by culturing the cells under different in-vitro conditions: i.e. in monolayer and in suspension culture in gelled agarose. Monolayer cultured chondrocyte phenotype was assayed by immunohistochemical staining with monoclonal antibodies against chondrocyte-specific aggrecan, type II and I collagen. Flow cytometry was used to quantify the proportions of chondrocytes expressing these extracellular matrix molecules in both culture conditions. To exclude the effects of cell-harvesting methods on the presence of cell-bound ECM molecules, non-proteolytic isolation procedures were used to obtain the chondrocytes for flow cytometry. Subconfluent cells from monolayer cultures were detached with EDTA. Chondrocytes cultured in gelled agarose were obtained after the agarose was enzymatically digested with agarase.

RESULTS

Immunohistochemical staining showed that monolayer-cultured chondrocytes, in the presence of serum, gradually lost the expression of chondrocyte-specific aggrecan and type II collagen, while type I collagen was increasingly expressed. Flow cytometry allowed monolayer cultured chondrocyte phenotype to be assessed reproducibly. Chondrocyte phenotype was characterized through the cell membrane-associated extracellular matrix antigens. EDTA, used to obtain single cells from monolayer cultures, did not affect the cell-associated matrix. Where the chondrocytes had been cultured in gelled agarose, flow cytometry allowed quantification of the percentages of chondrocytes maintaining or reexpressing their original phenotype. The agarase digestion procedure used to isolate the cells from the agarose gel did not affect the plasma membrane-associated extracellular matrix antigens.

CONCLUSION

Flow cytometry allows quantification of cells expressing aggrecan, type II and I collagen in their cell-associated extracellular matrix. A continuously increasing number of specific monoclonal antibodies will broaden the range of applications offered by this method.

Interpretation of ileal biopsies: morphological features in normal and diseased mucosa

One of the advantages of flexible colonoscopy is that the terminal ileum can easily be reached and biopsied by an experienced operator. Thus, the pathologist will, with increasing frequency, receive ileal biopsies from patients who have or may not have ileal disease and it is therefore useful to have a good knowledge of the spectrum of ileal mucosal histology and pathology, of its normal function, and of the changes seen in different conditions. It is also desirable to be aware of diseases that occur less frequently. The ileal microscopic features are related to its absorptive function on the one hand, and to non-specific and specific defence mechanisms of the organism against potential hazardous components on the other. As a consequence the mucosa features a constant physiological and controlled inflammatory process. Part of the ileal mucosal structure is determined by the presence of the gut-associated lymphoid tissue (GALT) which plays a key role in discriminating harmless nutrients and harmful pathogens. It will be important to distinguish this normal situation from alterations seen in infectious or inflammatory pathology. Further, because of the therapeutic implications, it is necessary that acute and chronic (idiopathic) inflammation are recognized. This will in general be possible by evaluating the composition of the inflammatory infiltrate and the occurrence of epithelial and mucosal architectural changes.

Current use of biologicals for the treatment of spondyloarthropathies

Spondyloarthropathies (SpA) are a group of related disorders. The hallmark symptoms include spondylitis, pauci-articular synovitis and enthesiopathy. In an important number of cases, subclinical gut inflammation with pathological findings resembling Crohn's disease can be found. Some of these patients may eventually develop overt Crohn's disease. Conventional medical therapy in patients with SpA consists of non-steroidal anti-inflammatory drugs (NSAIDs). Sulphasalazin can be co-administered, especially in cases of chronic synovitis or enthesiopathy. Recently, experience with anti-TNF-alpha monoclonal antibodies (infliximab), a new class of biological compounds, has opened new avenues for treating patients with SpA. In particular, infliximab used in two open studies gave significant benefit on the locomotor manifestations in patients with Crohn's disease, in patients with ankylosing spondylitis, undifferentiated SpA and psoriatic arthritis. Etanercept, another TNF-alpha antagonist (soluble receptor), was shown to induce benefit in a placebo-controlled study in patients with psoriatic arthritis. The relationship between SpA and inflammatory bowel disease lead to the hypothesis that interfering with gut inflammation in patients with SpA would yield a potential target for modulating the synovitis in these patients. Thus, besides TNF-alpha blockade, other strategies with potential efficacy can be envisioned, such as IL-10, ICAM-1 antisense or anti-(4)beta(7) antibodies.

Comparative study of the synovial histology in rheumatoid arthritis, spondyloarthropathy, and osteoarthritis: influence of disease duration and activity

OBJECTIVES

To compare the macroscopic and microscopic characteristics of synovial tissue in rheumatoid arthritis (RA), spondyloarthropathy (SpA), and osteoarthritis (OA) after exclusion of possible biases induced by disease duration or activity, or both.

METHODS

Synovial biopsy specimens were obtained by needle arthroscopy in patients with early RA (n=16), late RA (n=14), early SpA (n=23), and OA (n=12). Macroscopic and microscopic features were scored on a four point scale and analysed as a function of disease duration (early versus late RA), local and systemic disease activity, and diagnosis.

RESULTS

Except for the maximal synovial lining thickness, no significant differences were seen between early and late RA. For disease activity, synovial histology was only weakly correlated with C reactive protein in RA, but seemed to be strongly dependent on effusion of the biopsied joint in all disease groups. After stratification for local disease activity, no disease related differences were found in patients without joint effusion. In contrast, important differences were found between patients with RA and SpA with active joint effusion. Synovial vascularity was macroscopically increased in SpA versus RA (p=0.017). A straight vessel pattern was only seen in RA, while tortuous vessels were preferentially seen in SpA. Vascularity was also microscopically increased in SpA compared with RA (p=0.031), and correlated with the macroscopic vascularity (r(s)=0.36, p=0.036). CD3+ (p=0.008), CD4+ (p=0.008), and CD20+ (p=0.024) lymphocytes were overrepresented in RA compared with SpA. The integrin expression in RA was characterised by a decrease of alphaVbeta3 in the synovial lining (p=0.006) and an increase of alphaVbeta5 in the sublining (p<0.001).

CONCLUSIONS

The immune architecture of the synovial membrane is more dependent on local disease activity than on disease duration. Synovium obtained from clinically affected joints shows important histological differences between RA and SpA.

Spondyloarthropathy is underestimated in inflammatory bowel disease: prevalence and HLA association

OBJECTIVE

To determine the overall prevalence of spondyloarthropathy (SpA) among patients with inflammatory bowel disease (IBD) [Crohn's disease (CD) and ulcerative colitis (UC)].

METHODS

One hundred three consecutive patients with IBD from a gastroenterology unit were questioned and examined for SpA symptoms. Patients previously diagnosed with SpA were excluded. All patients were questioned and examined for SpA symptoms such as inflammatory back pain, joint swelling, enthesitis, and psoriasis or a specific family history. Radiographs were taken of all sacroiliac joints. HLA loci A, B, C, and DR were determined in all patients.

RESULTS

Thirty-nine percent of the patients with IBD had clinical articular manifestations: 30% had inflammatory back pain, 10% had synovitis, and 7% had a peripheral enthesopathy. The majority (90%) of patients with rheumatic complaints fulfilled the classification criteria for SpA and 10% fulfilled the criteria for ankylosing spondylitis. Asymptomatic sacroiliitis was found in an additional 18% of the patients. Moreover, sacroiliitis, symptomatic or asymptomatic, was related to the disease duration. HLA-B27 conferred an additional risk for inflammatory low back pain in patients with IBD.

CONCLUSION

Articular involvement in IBD can be classified as SpA. The appearance of SpA occurs irrespective of the extent of the bowel disease. Moreover, asymptomatic sacroiliac involvement is a common manifestation in IBD and it is related to disease duration, suggesting evidence for a related pathogenic mechanism.

The influence of hydrocortisone on aggrecan metabolism in human articular chondrocyte cultures: comparison of two different matrices

OBJECTIVE

Numerous reports of negative effects as well as protective effects of glucocorticoids on articular cartilage convinced us to study the influence of hydrocortisone on aggrecan synthesis of isolated phenotypically stable human articular chondrocytes cultured in two different matrices.

METHODS

Macroscopically normal human articular cartilage was obtained from femoral condyles within 24 hours postmortem. Chondrocytes were isolated and cultured in gelled agarose or in alginate. After 14 days in culture, hydrocortisone was added for 5 days at concentrations ranging from 0.005 microgram to 1 mg/ml for the agarose cultures and from 0.005 microgram to 1 microgram/ml for the alginate culture system. Aggrecan synthesis was measured by the incorporation of 35Sulphate, and the proportion of neosynthesized aggrecan that bound to hyaluronan to form aggrecan aggregates was analyzed by gel chromatography.

RESULTS

At concentrations from 0.005 to 1 microgram/ml, hydrocortisone was found to produce a similar dose-dependent stimulation of aggrecan synthesis in both matrices. The synthesis of aggrecans remained at the same level for concentrations of 1 microgram/ml up to 100 micrograms/ml of hydrocortisone. When supraphysiological concentrations of hydrocortisone were added the aggrecan synthesis rate plateau declined. Simultaneously with the increase in aggrecan synthesis, the proportion of low-molecular weight 35S-proteoglycans decreased in favour of 35S-aggrecan aggregates and monomers in the agarose system. The chondrocytes cultured in alginate showed this increase of aggrecan aggregates and monomeric aggrecans in both the cell-associated and the inter-territorial matrix.

CONCLUSION

Hydrocortisone is a stimulator of aggrecan synthesis by normal human articular chondrocytes cultured in vitro. The two culture systems (agarose and alginate) tested in this experiment showed a comparable aggrecan synthesis rate, increasing under the influence of hydrocortisone at concentrations up to 1 microgram/ml. The proportions of 35Sulphate incorporated in aggrecan aggregates and monomeric aggrecan were also higher under the influence of hydrocortisone.

Focal up-regulation of E-cadherin-catenin complex in inflamed bowel mucosa but reduced expression in ulcer-associated cell lineage

The E-cadherin-catenin complex is important for the maintenance of epithelial architecture. We studied its expression in Crohn disease, ulcerative colitis, acute ileitis, and controls. Immunohistochemical stainings for E-cadherin, alpha-catenin, beta-catenin and gamma-catenin were performed. E-cadherin messenger RNA (mRNA) was detected using riboprobes. In active inflammation, there was up-regulation of the complex. In particular, epithelium adjacent to ulcers showed increased expression of protein and mRNA, but in ulcer-associated cell lineage, the intensity of staining was weak to negative. In focal inflammation, up-regulation was found in affected areas. Reparative epithelium growing over denuded areas showed weaker expression. Since structural or functional perturbation in any of the molecules of the E-cadherin-catenin complex results in loss of intercellular adhesion, the preexistent epithelium may benefit from up-regulation to try to maintain its normal architecture under inflammatory conditions. Reduced expression in reparative epithelium and ulcer-associated cell lineage could facilitate the motility of these cells.

Occurrence of scleroderma in monozygotic twins

Familial occurrence of scleroderma is rare and concordance for the disease in twins has been reported exceptionally. We describe 2 female identical twin pairs concordant for scleroderma. The first twin pair was diagnosed with the systemic form of scleroderma, the second pair with the localized form.

The zygapophyseal joint determines morphology of the enthesophyte

OBJECTIVE

To determine the contribution of zygapophyseal joint ankylosis on the morphology of the spinal enthesophyte.

METHODS

Radiographic analysis of lumbar spine in ankylosing spondylitis (AS) patients with different types of enthesophytes. Computerized axial tomographic analysis of the zygapophyseal (ZA) joints of the lumbar spine of AS patients with chunky enthesophytes and bridging syndesmophytes.

RESULTS

Four patients with AS were selected for the simultaneous presence of chunky enthesophytes and bridging syndesmophytes. At the levels with bridging syndesmophytes at least one ZA joint was ankylosed. At the levels with chunky enthesophytes alone the ZA joints were not ankylosed.

CONCLUSION

The morphology of the enthesophytes is influenced by the presence of ankylosis in the ZA joint.

Effects of a loading dose regimen of three infusions of chimeric monoclonal antibody to tumour necrosis factor alpha (infliximab) in spondyloarthropathy: an open pilot study

OBJECTIVE

To evaluate the efficacy and safety of a loading dose regimen of three intravenous infusions with infliximab in patients with active spondyloarthropathy.

METHODS

A monocentre, open-label pilot study of 21 patients with different subtypes of spondyloarthropathy was conducted. Treatment resistant patients with active disease (fulfilling inclusion criteria) received three infusions of 5 mg/kg infliximab (at weeks 0, 2, and 6). Standard clinical assessments were performed at baseline, and on days 3, 7, and 14, and from then on every two weeks. In patients who fulfilled criteria for ankylosing spondylitis, axial assessment was performed at baseline and on days 14, 42, and 84.

RESULTS

In all global assessments (visual analogue scale of patient global assessment, patient pain assessment, doctor global assessment), erythrocyte sedimentation rate, and C reactive protein, a highly significant decrease could be seen already at day 3 (compared with baseline), which was maintained up to day 84. In patients with peripheral disease (n=18), tender and swollen joint count significantly decreased. In patients with axial disease (n=11), functional and disease activity indices significantly improved. Moreover in eight patients with psoriatic arthritis a significant decrease of the psoriasis area and severity index was observed. The treatment was well tolerated in all patients; no significant adverse events were seen.

CONCLUSION

In this open-label pilot study of a loading dose regimen of three infusions of chimeric monoclonal antibody to tumour necrosis factor alpha in patients with active spondyloarthropathy, there was a fast and significant improvement of axial and peripheral articular manifestations, without major adverse experiences.

Human cartilage gp-39+,CD16+ monocytes in peripheral blood and synovium: correlation with joint destruction in rheumatoid arthritis

OBJECTIVE

To investigate the expression of human cartilage (HC) gp-39, a possible autoantigen in rheumatoid arthritis (RA), in peripheral blood and synovium, to characterize its cellular source, and to analyze correlations with clinical features.

METHODS

The expression of HC gp-39 in synovium and peripheral blood mononuclear cells (PBMC) was assessed by immunohistochemistry and flow cytometry. Synthesis and secretion were investigated by both reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay.

RESULTS

PBMC expressing HC gp-39 were increased in RA patients compared with spondylarthropathy patients (P = 0.0029) and with healthy control subjects (P = 0.0013). HC gp-39+ cells were also slightly overrepresented in RA synovium (P = 0.01). In both blood and synovium, HC gp-39+ cells were identified as CD14dim,CD16+ monocytes, a phenotype which can differentiate from classic CD14++ monocytes by maturation in vitro. HC gp-39 messenger RNA was detected in RA synovium and PBMC, and PBMC secreted HC gp-39 in vitro. The number of HC gp-39+ PBMC correlated with serum levels of C-reactive protein (r = 0.39, P = 0.003) and HC gp-39 (r = 0.52, P = 0.014). HC gp-39 expression in RA synovial lining correlated with joint destruction (r = 0.77, P < 0.001).

CONCLUSION

CD16+ monocytes, a cellular source of HC gp-39 in vivo, are overrepresented in both RA peripheral blood and synovial tissue. The presence of HC gp-39+ cells in RA synovium is correlated with the degree of joint destruction. These data support a role of these cells in the local autoimmune response that leads to chronic inflammation and joint destruction.

Influence of aging on the synthesis and morphology of the aggrecans synthesized by differentiated human articular chondrocytes

OBJECTIVE

Synthesis rates of aggrecans by phenotypically stable human articular chondrocytes and the immobilization of these aggrecans in large aggregates were used as variables reflecting the capability of these cells of restoring the extracellular matrix of articular cartilage in vivo in an aging population.

DESIGN

Human articular chondrocytes were isolated from articular cartilage obtained from 33 different donors at autopsy. The chondrocytes were cultured in gelled agarose. Synthesis of aggrecans was investigated using Na(2)(35)SO(4)as a radioactive precursor after a 2-week culture period. Electron microscopic study of aggrecan aggregates was done on the macromolecules accumulated over 3 weeks in culture by the chondrocytes obtained from eight other donors with increasing ages.

RESULTS

Sulfate incorporation rates into aggrecans correlated inversely with the age of the donor. The value of sulfate incorporation in aggrecans for chondrocytes obtained from mature cartilage of a 20-year-old individual in this system drops to 50% and 25% for chondrocytes obtained from 45- and 69-year-old individuals respectively. Electron microscopic study of aggrecan aggregates showed that the 'de novo' synthesized hyaluronan molecules were fully loaded with aggrecans. Mature human articular cartilage cells were found to synthesize an aggrecan aggregate which carried an average number of 11.7 to 13.1 aggrecans. Cells obtained from immature donors synthesized aggrecan aggregates of which the hyaluronan chain carried twice the amount of aggrecans. These immature human articular cartilage cells were also found to synthesize significant proportions of large aggrecan aggregates with 20 to over 100 aggrecans immobilized on a single hyaluronan chain. The proportions of these large aggrecan aggregates decreased with increasing age of the donors of the chondrocytes.

CONCLUSION

The declining aggrecan synthesis rates and the decreased capability of assembling large molecular size aggregates with increasing age in humans illustrates a progressive failure of the repair function of articular cartilage cells in humans.

Is 99mTc human immunoglobulin G scintigraphy (HIG-scan) useful for the detection of spinal inflammation in ankylosing spondylitis?

OBJECTIVE

To determine the effectiveness of technetium-99m labelled polyclonal human immunoglobulin G (HIG-scan) scintigraphy to detect spinal inflammation in patients with ankylosing spondylitis.

METHODS

Six ankylosing spondylitis (AS) patients with inflammatory axial pain and 3 spinal osteoarthritis (OA) patients with mechanical axial pain underwent an HMDP scan and an HIG-scan.

RESULTS

In both AS and spinal OA patients complaining of axial back pain, mechanical and inflammatory axial pain, bone scintigraphy revealed foci of markedly increased tracer accumulation. An HIG-scan of the region of increased uptake on bone scintigraphy did not reveal increased tracer accumulation in either group of patients.

CONCLUSION

The data suggest that the HIG-scan is not useful in detecting inflammatory spinal lesions in ankylosing spondylitis.

Chemical agents and enzymes used for the extraction of gut lymphocytes influence flow cytometric detection of T cell surface markers

Chemical agents (DTT, EDTA) and enzymes (collagenase, DNAse) are often used for the generation of a single cell suspension from tissue samples. In this study, flow cytometry was used to examine the effect of chemical agents and enzymes on the expression of cell membrane markers of T lymphocytes from tonsils and peripheral blood. Expression of CD4, CD8, CD25, CD38, L-selectin, CD44, alphaEbeta7 and alpha4beta7 were studied. Incubation of lymphocytes with DTT and EDTA resulted in a decrease of CD38, alphaEbeta7 and alpha4beta7 expression. Incubation with collagenase A and DNAse resulted in a decrease of CD25, L-selectin, alphaEbeta7 and alpha4beta7. The results of this study indicate that a careful interpretation is necessary for phenotypic descriptions of lymphocyte populations obtained by enzymatic isolation techniques.

Broadening of the T cell receptor spectrum among rheumatoid arthritis synovial cell-lines in relation to disease duration

OBJECTIVE

The aim of the study was to evaluate the T cell receptor (TCR) family usage in T cell-lines from subcutaneous nodules and synovium from patients with rheumatoid arthritis (RA), with specific reference to the duration of symptoms. In vitro adherence characteristics of nodular T cells was studied as well.

METHODS

Monoclonal antibodies were used to determine the distribution of TCR families in T cell-lines from synovium of patients with early and long-standing RA, from rheumatoid nodules and control tissues. An in vitro binding assay with T cell-lines from 2 rheumatoid nodules was performed.

RESULTS

In early RA synovium, a restricted TCR family usage was observed in 5 out of 8 patients, contrary to long-standing disease, peripheral blood, ileum and colon. In RA nodules, a similar degree of restriction was noted. Moreover, the same TCR family was overexpressed by T cell-lines from different nodules derived from the same patient. T cell-lines from rheumatoid nodules demonstrated a preferential in vitro adherence to rheumatoid synovium and rheumatoid nodules, while no binding was observed on skin or tonsil.

CONCLUSION

The TCR spectrum among RA synovial cell-lines broadens in relation to the disease duration. The overexpression of the same TCR family in different rheumatoid nodules from the same patients, and the in vitro adherence of T cell-lines from rheumatoid nodules may be indicative for recirculation between the different disease manifestations in RA.

Subclinical gut inflammation in spondyloarthropathy patients is associated with upregulation of the E-cadherin/catenin complex

OBJECTIVE

Previously an upregulation of E-cadherin and its associated molecules alpha-catenin, beta-catenin and plakoglobin has been demonstrated in clinically overt inflammatory bowel disease (IBD). The aim of this study was to investigate the expression of the E-cadherin/catenin complex in subclinically inflamed bowel mucosa from spondyloarthropathy (SpA) patients.

METHODS

Ileal and colonic biopsy specimens from 19 SpA patients with subclinical inflammatory gut lesions and from seven controls were stained with monoclonal antibodies against E-cadherin, beta-catenin and plakoglobin and a polyclonal antibody against alpha-catenin. E-cadherin mRNA was detected using a riboprobe. Inflammation was histologically classified into acute, chronic active and chronic quiescent forms.

RESULTS

In acute and chronic active bowel inflammation of SpA patients, upregulation of the E-cadherin/catenin glycoprotein complex could be observed. Chronic lesions in a quiescent state did not show such an upregulation. Furthermore, chronic inflammation was associated with an increase in E-cadherin mRNA.

CONCLUSIONS

As some of the SpA patients with subclinical gut inflammation develop IBD, upregulation of the E-cadherin/catenin complex in inflamed bowel mucosa from SpA patients may point to early cellular changes in the development of IBD. However, at present it cannot be excluded that increased E-cadherin/catenin complex expression is a bystander phenomenon of active inflammation.

Opportunities for immune modulation in the spondyloarthropathies with special reference to gut inflammation

The spondyloarthropathies (SpA) are a related group of disorders, characterized primarily by spondylitis, pauci-articular arthritis and enthesitis. The presence of subclinical gut inflammation in patients with SpA ranges from 25 to 75%, depending upon the type of SpA. Several data suggest that the association between gut inflammation and synovitis reflects an etiopathogenetic relationship, and that strategies which interfere with the gut inflammation may also modulate the synovitis. Here we review some standard as well as experimental drugs used in the treatment of patients with inflammatory bowel disease and discuss what is known about their effect on SpA-related locomotor manifestations. For the more experimental drugs, such as cytokines, anticytokines and anti-adhesion compounds, clinical trials in patients with SpA are still very scarce.

Needle arthroscopy of the knee with synovial biopsy sampling: technical experience in 150 patients

Needle arthroscopy is an office-based technique allowing direct visualisation of the knee cavity and selective sampling of the synovial membrane. We performed needle arthroscopy in 150 patients with synovitis of the knee (1) to evaluate the diagnostic potential in early arthritis, (2) to perform therapeutic lavage in persistent inflammatory synovitis and (3) to assess the balance between technical feasibility, safety and patient comfort on the one hand, and the relevance of the obtained macro- and microscopic information for diagnosis and research purposes on the other. After disinfection of the leg and local anaesthesia of the skin and joint, a 1.8-2.7 mm needle arthroscope was introduced into the knee. Synovial fluid was aspirated and lavage of the joint cavity was performed to allow macroscopic evaluation of hyperaemia and hypertrophy of the synovial membrane. Biopsies were taken at inflamed sites, followed by another lavage to remove blood and debris. Needle arthroscopy of the knee is a simple and easy to perform technique made particularly attractive by the local anaesthesia and the ambulatory setting. It allows good macroscopic evaluation of synovial inflammation and selective sampling of the synovial membrane. Biopsies are suitable for RNA and DNA extraction, bacterial or lymphocyte culture, and cell isolation. Because samples were sometimes too small for representative histology, we switched from a 1.8 mm to a 2.7 mm biopsy forceps with good results. In nearly all cases the arthroscopy was well tolerated. Moreover, some patients reported relief of symptoms and even improvement of mobility after lavage of the inflamed joint. No major complications were noted. It was concluded that needle arthroscopy of the knee is a simple, safe and well-tolerated technique, with promising perspectives as a diagnostic, scientific and possibly therapeutic tool in rheumatic diseases.