Faecal levels of calprotectin in systemic sclerosis are stable over time and are higher compared to primary Sjögren's syndrome and rheumatoid arthritis.

INTRODUCTION: Faecal calprotectin (FC) has been proposed to be a biomarker of gastrointestinal (GI) disease in systemic sclerosis (SSc). The purpose of this study was to extend cross-sectional observations and prospectively assess the variability of FC over time in SSc patients. We also aimed to examine FC in relation to immunosuppressive therapy. Finally we wanted to analyse FC in other rheumatic diseases to evaluate the specificity of FC for SSc GI disease. METHODS: FC was measured in consecutive patients with SSc, primary Sjögren's syndrome (pSS), rheumatoid arthritis (RA) and in healthy hospital workers. The intraindividual variability of FC in SSc was assessed with intra class correlation (ICC) and κ statistics. Associations between FC and objective markers of GI disease and immunosuppressive medication were investigated. RESULTS: FC was associated with micronutrient deficiency and GI pathology as assessed by cineradiography confirming our previous results. FC showed only a limited intra-individual variation in SSc, ICC = 0.69 (95% confidence interval, CI: 0.57-0.78) and κ = 0.64 (95% CI: 0.56-0.73). Generalised immunosuppression did not have any significant impact on FC. FC was significantly higher in SSc patients compared to patients with pSS or RA as well as compared to healthy subjects. CONCLUSIONS: FC is a promising non-invasive biomarker for GI disease in SSc. In view of stable levels over time, FC could be a useful marker when novel, more specific drugs targeting the GI tract in SSc will be introduced.

Biomarkers from bronchoalveolar lavage fluid in systemic sclerosis patients with interstitial lung disease relate to severity of lung fibrosis.

OBJECTIVES: Decision on treatment of systemic sclerosis (SSc) related interstitial lung disease (ILD) largely relies on the findings on high resolution computed tomography (HRCT) and there is a need for improvement in assessment of the fibrotic activity. The objectives of this study were to study biomarkers in bronchoalveolar lavage fluid (BALF) from SSc patients with ILD and to relate the findings to the severity and activity of lung fibrosis. METHODS: Fifteen patients with early SSc and 12 healthy controls were subjected to BAL. Cell counts and analyses of CXCL5, CXCL8 and S100A8/A9 were performed in BALF and serum. COMP and KL-6 were measured in serum. HRCT of lungs was quantified for ground glass opacities (GGO), reticulation and traction bronchiectases. RESULTS: BALF concentrations of CXCL8 (p < 0.001), CXCL5 (p = 0.002) and S100A8/A9 (p = 0.016) were higher in patients than controls. Serum KL-6 (p < 0.001) was increased in SSc patients and correlated with BALF concentration of eosinophils (rS = 0.57, p = 0.027). Patients with more widespread GGO on HRCT were characterised in BALF by a higher eosinophil count (p = 0.002) and in serum by higher KL-6 (p = 0.008). Patients with more fibrosis were characterised in BALF by higher eosinophil count (p = 0.014), higher CXCL8 (p = 0.005) and S100A8A/A9 (p = 0.014) concentration and in serum by a higher serum COMP (p = 0.023). CONCLUSIONS: In SSc related ILD, biomarkers from BALF and serum correlate to findings on HRCT suggesting usefulness as markers of presence and extent of lung fibrosis.

Assessment of capillary density in systemic sclerosis with three different capillaroscopic methods.

OBJECTIVES: Capillary abnormalities, such as the enlargement and/or disappearance of capillary loops, occur early in the majority of patients with systemic sclerosis (SSc). The aim of this study was to compare three capillaroscopic methods of determining the capillary density in patients with SSc. METHODS: Two of the three methods involved stereo-zoom microscopy at a magnification of 20 times, used either for direct counting, or with a camera and imaging software for determination of the capillary density on coded images. The third method was computerised nailfold video capillaroscopy with 300 x magnification using coded images. The capillary density (loops/mm) was determined on the fourth finger of the non-dominant hand with all three methods in 40 patients, 32 with limited cutaneous SSc (lcSSc) and 8 with diffuse cutaneous SSc (dcSSc), and in 21 healthy control subjects. RESULTS: The median values of capillary density assessed with the three methods were: 4.3, 5.4 and 6.1 loops/mm in lc-SSc patients, 4.5, 5.0 and 6.3 loops/mm in dcSSc patients, and 7.0, 7.0 and 6.9 loops/mm in the controls. Capillary density was thus lower in lcSSc and dcSSc patients than in the controls according to all three methods. Agreement between the three methods was good in the controls. In patients, direct counting resulted in lower values than in the two computer-based methods. CONCLUSIONS: Assessment of capillary density with three different methods showed good agreement between methods. All methods could differentiate between SSc patients and controls.

Increased serum COMP predicts mortality in SSc: results from a longitudinal study of interstitial lung disease.

OBJECTIVES: COMP is a regulator of assembly and maintenance of the fibrillar collagen I and II networks. Serum COMP reflects skin fibrosis in SSc. The purpose of this study was to examine whether serum COMP reflects fibrotic lung involvement in SSc patients and to study if serum COMP predicts mortality. METHODS: Three overlapping cohorts of 244 SSc patients were studied. Two hundred and eighteen patients were included to study survival, 80 patients to study longitudinal changes of pulmonary function tests and 64 to study pulmonary involvement assessed by high-resolution CT (HRCT). Serum COMP was measured by ELISA. Skin involvement was assessed with the modified Rodnan skin score (mRSS). Data about survival were obtained from the central population registry. RESULTS: Serum COMP measured within 5 years after the first non-Raynaud's manifestation was a predictor of death, and crude mortality increased by 6% for each COMP unit elevation. Serum COMP levels >15 U/l were associated with a 3.13-fold (95% CI 1.73, 5.64; P < 0.001) increased risk of death. During the first year of follow-up serum COMP and vital capacity (VC) changed inversely (r(s) = -0.32; P = 0.005), but there were no correlations between baseline serum COMP and concurrent findings by spirometry or HRCT. CONCLUSION: Serum COMP early in disease is a predictor of mortality in SSc patients. Serum COMP changes in parallel with lung fibrosis as measured by VC, but the release from fibrotic skin possibly obscures the influx from the lungs and therefore serum COMP seems to have little utility as a marker of lung fibrosis.

A multicentre study on the reliability of qualitative and quantitative nail-fold videocapillaroscopy assessment.

OBJECTIVE: To investigate the inter- and intra-observer reliability of both qualitative and quantitative parameters used in the assessment of nail-fold capillaroscopy images. METHODS: Fifty mosaic nail-fold images of healthy controls (n = 10), patients with primary RP (n = 10) and SSc (n = 30) were assessed in random order by two blinded observers on two occasions at centres in Sweden, UK and The Netherlands. Each image was therefore scored by six observers twice. RESULTS: Inter- and intra-observer reliability of quantitative parameters showed substantial to almost perfect agreement [inter- and intra-observer weighted κ's for the number of widened capillaries was 0.75 and 0.87 and giant capillaries was 0.84 and 0.92, intra-class correlation coefficients (ICCs) for capillary density was 0.87 and 0.92 and total loop width was 0.94 and 0.98, respectively]. Qualitative parameters including architecture, avascularity, haemorrhage, crossed, ramified and bushy capillaries showed moderate to substantial inter-observer reproducibility (weighted κ ranging from 0.47 to 0.73), and substantial intra-observer repeatability (weighted κ ranging from 0.71 to 0.80), whereas the scoring of tortuous and bizarre capillaries showed poor inter-observer and substantial intra-observer agreement (inter-observer weighted κ's was 0.39 and 0.21 and intra-observer weighted κ's was 0.68 and 0.76, respectively). CONCLUSION: All quantitative and certain qualitative parameters are highly reliable in terms of inter- and intra-observer agreement. A combination of parameters with the highest reliability should be incorporated into future capillaroscopic scoring systems in studies of prediction and monitoring of SSc spectrum disorders.

Managing work life with systemic sclerosis.

OBJECTIVE: To explore how individuals with SSc manage their work life. METHODS: We conducted four focus group interviews, which included 17 patients currently working at least 20 h per week. The interviews were recorded and transcribed verbatim. The transcribed texts were analysed according to thematic content analysis. Relevant statements that generated preliminary categories were identified, after which themes and underlying subthemes were generated. RESULTS: The participants perceived their work role as being important, giving them a structure in everyday life and a sense of being useful members of society. Work and private life were interacting, and different adjustments had been developed to create a satisfactory balance of activities in daily life. Three themes emerged: adjustment of work situation, adapting to own resources and disclosing limitations. Reduced working hours, flexibility in the workplace concerning time schedule, room and tasks were all valuable adjustments, and were dependent on the employer, fellow workers as well as the individual's attitude towards informing employer and colleagues about his/her limitations. The participants had simplified and rationalized a lot of household chores and pointed to the importance of prioritizing meaningful activities, as well as the necessity of having time for rest and recovery. CONCLUSIONS: Reduced working hours, work flexibility and prioritizing meaningful activities and recovery were important factors in order to manage work life. Intervention, including problem-solving techniques and re-designing of activities in daily life, could be useful to coach individuals towards finding a balance in their work life.

Increased cysteinyl-leukotrienes and 8-isoprostane in exhaled breath condensate from systemic sclerosis patients.

OBJECTIVES: SSc is a systemic CTD characterized by fibrosis in skin and internal organs. Interstitial lung disease is a frequent complication with fibrosis in the lung parenchyma. The fibrotic process is believed to be influenced by leukotrienes (LTs) and also by oxidative stress. The aim of this study was to investigate the amount of LTs and 8-isoprostane, a marker of oxidative stress, in exhaled breath condensate (EBC) from SSc patients. METHODS: Twenty-two SSc patients with median disease duration of 2.1 years were investigated. Fifteen patients had lcSSc, four patients had dcSSc and three patients only fulfilled criteria for limited SSc. Sixteen healthy controls were enrolled. Cysteinyl-LTs (CysLTs), LTB4 and 8-isoprostane were measured in EBC with EIA and related to the radiologic extent of pulmonary fibrosis. RESULTS: Compared with controls, SSc patients displayed higher median (interquartile range) CysLT [6.1 (5.3-6.8) vs 4.9 (3.7-6.3) pg/ml; P=0.040], 8-isoprostane [0.23 (0.20-0.46) vs 0.19 (0.12-0.20) pg/ml; P=0.0020], but similar levels of LTB4 [0.70 (0.50-0.83) vs 0.60 (0.42-0.70) pg/ml]. CysLT correlated to LTB4, while 8-isoprostane did not correlate to any of the LTs. None of the biomarkers measured in EBC correlated to radiologic findings. CONCLUSION: Increased levels of CysLT and 8-isoprostane in EBC from patients with SSc reflect the inflammatory pattern involving LTs as well as oxidative stress. These findings may indicate a possible non-invasive assessment of pulmonary involvement in SSc with a potential value for assessment of disease progress and therapy evaluation.

Interleukin-15 attenuates transforming growth factor-ß1-induced myofibroblast differentiation in human fetal lung fibroblasts.

OBJECTIVE: Fibroproliferative diseases are common causes of morbidity and mortality. Interleukin-15 (IL-15) is a pleiotropic cytokine with multiple effects on cells of the immune system. Although IL-15 is also expressed in mesenchymal cells, its effects on the development of fibrosis are unknown. We have previously described an association between serum IL-15 levels and the extent of pulmonary fibrosis in the connective tissue disease systemic sclerosis, suggesting that IL-15 may have profibrotic effects. To test this hypothesis, we studied the effects of IL-15 on myofibroblast differentiation, an in vitro model of fibrosis development. METHODS: We used human fetal lung fibroblasts for the cytokine stimulation. As a marker of myofibroblast differentiation, α-smooth muscle actin (α-SMA) was analyzed by western blot and quantitative real-time PCR. The well-known profibrotic cytokine, transforming growth factor-ß1(TGF-ß1), was used for comparison, and TGF-ß signaling paths were also studied. RESULTS: IL-15 did not induce α-SMA expression, a marker for myofibroblast differentiation. Unexpectedly, IL-15 counteracted TGF-ß1-mediated α-SMA expression. Moreover, TGF-ß1-induced expression of collagen, fibronectin and connective tissue growth factor was attenuated by addition of IL-15. There was no effect of IL-15 on early events in the TGF-ß signaling cascades. CONCLUSION: IL-15 has anti-fibrotic properties that, speculatively however, may be insufficient in systemic sclerosis.

Pain, fatigue and hand function closely correlated to work ability and employment status in systemic sclerosis.

OBJECTIVE: To identify factors, individual and work related, influencing work ability, and to assess the association between work ability and employment status, activities of daily life (ADLs) and quality of life in patients with SSc. METHODS: Fifty-seven consecutive patients (53 females/4 males) with SSc (47 lcSSc/10 dcSSc) were included. Median age was 58 [interquartile range (IQR) 47-62] years and disease duration 14 (9-19) years. The patients were assessed for socio-demographic characteristics, disease parameters, symptoms, work ability, empowerment and adaptations in a workplace, social support, ADLs and quality of life. RESULTS: Work ability, assessed with the Work Ability Index (WAI) could be evaluated in 48 of 57 patients. The correlation between employment status and WAI was good (r(s) = 0.79, P < 0.001). Thirteen patients had good or excellent WAI, 15 had less good and 20 had poor WAI. There were no significant differences between subgroups of WAI and socio-demographic characteristics, disease duration or degree of skin and lung involvement. However, patients with good WAI expressed milder perceived symptoms (pain, fatigue and impaired hand function; P < 0.001). Patients with better WAI had better competence (P < 0.001), better possibility of adaptations at work (P < 0.01) and impact at work (P < 0.01) than those with poorer WAI. CONCLUSIONS: In SSc, pain, fatigue and impaired hand function have a dominant impact on the WAI. Employment interventions should include support in job adaptations as well as self-management strategies to help patients deal with pain and fatigue and to enhance the confidence to perform their work.

Causes and risk factors for death in systemic sclerosis: a study from the EULAR Scleroderma Trials and Research (EUSTAR) database.

OBJECTIVES: To determine the causes and predictors of mortality in systemic sclerosis (SSc). METHODS: Patients with SSc (n=5860) fulfilling the American College of Rheumatology criteria and prospectively followed in the EULAR Scleroderma Trials and Research (EUSTAR) cohort were analysed. EUSTAR centres completed a structured questionnaire on cause of death and comorbidities. Kaplan-Meier and Cox proportional hazards models were used to analyse survival in SSc subgroups and to identify predictors of mortality. RESULTS: Questionnaires were obtained on 234 of 284 fatalities. 55% of deaths were attributed directly to SSc and 41% to non-SSc causes; in 4% the cause of death was not assigned. Of the SSc-related deaths, 35% were attributed to pulmonary fibrosis, 26% to pulmonary arterial hypertension (PAH) and 26% to cardiac causes (mainly heart failure and arrhythmias). Among the non-SSc-related causes, infections (33%) and malignancies (31%) were followed by cardiovascular causes (29%). Of the non-SSc-related fatalities, 25% died of causes in which SSc-related complications may have participated (pneumonia, sepsis and gastrointestinal haemorrhage). Independent risk factors for mortality and their HR were: proteinuria (HR 3.34), the presence of PAH based on echocardiography (HR 2.02), pulmonary restriction (forced vital capacity below 80% of normal, HR 1.64), dyspnoea above New York Heart Association class II (HR 1.61), diffusing capacity of the lung (HR 1.20 per 10% decrease), patient age at onset of Raynaud's phenomenon (HR 1.30 per 10 years) and the modified Rodnan skin score (HR 1.20 per 10 score points). CONCLUSION: Disease-related causes, in particular pulmonary fibrosis, PAH and cardiac causes, accounted for the majority of deaths in SSc.

Presence of CD4+CD8+ double-positive T cells with very high interleukin-4 production potential in lesional skin of patients with systemic sclerosis.

OBJECTIVE: Fibrotic skin changes in systemic sclerosis (SSc) are preceded by the appearance of an inflammatory infiltrate rich in T cells. Since no direct comparison with T cells in normal skin has been performed previously, this study was undertaken to functionally characterize T cells in the skin of patients with early active SSc and in normal skin. METHODS: We characterized coreceptor expression, T cell receptor (TCR) usage, cytokine production, and helper and cytolytic activity of T cell lines and clones established from skin biopsy specimens from 6 SSc patients and 4 healthy individuals. Immunofluorescence analysis of skin biopsy and peripheral blood samples was performed to confirm the presence of specific subsets in vivo. RESULTS: A distinct subset expressing both CD4 and CD8alpha/beta coreceptors at high levels (double-positive [DP]) was present in T cell lines from SSc and normal skin. DP T cells actively transcribed both accessory molecules, exerted clonally distributed cytolytic and helper activity, and expressed TCR clonotypes distinct from those in CD4+ or CD8+ single-positive (SP) T cells. In SSc skin, DP T cells produced very high levels of interleukin-4 (IL-4) compared with CD4+ SP T cells. Furthermore, DP T cells were directly identified in SSc skin, thus providing evidence that they are a distinct subset in vivo. CONCLUSION: The present findings show that T cells with the unusual CD4+CD8+ DP phenotype are present in the skin. Their very high level of IL-4 production in early active SSc may contribute to enhanced extracellular matrix deposition by fibroblasts.

Serum IL-15 in patients with early systemic sclerosis: a potential novel marker of lung disease.

The pathogenesis of systemic sclerosis (SSc) is characterized by autoimmunity, vasculopathy and fibrosis. IL-15 is a pleiotropic cytokine that has impact on immune, vascular and connective tissue cells. We therefore investigated IL-15 in the circulation of patients with early SSc and explored possible associations of serum IL-15 with vasculopathy and fibrosis. Serum levels of IL-15 were analysed in 63 consecutive patients with SSc of disease duration less than 4 years and without disease-modifying treatment. Thirty-three age-matched healthy control individuals were enrolled. Serum IL-15 levels were increased in the sera of SSc patients compared with that of healthy control individuals (P < 0.01). Serum IL-15 levels correlated with impaired lung function, assessed both by the vital capacity (P < 0.05) and by the carbon monoxide diffusion capacity (P < 0.05). The association between IL-15 and the vital capacity remained after multiple linear regression analysis. Patients with intermediate serum IL-15 levels had a higher prevalence of increased systolic pulmonary pressure compared with patients with either low or high serum IL-15 levels (P < 0.05). Moreover, increased serum IL-15 levels were associated with a reduced nailfold capillary density in multivariable logistic regression analysis (P < 0.01). Serum IL-15 levels also correlated inversely with the systolic blood pressure (P < 0.01). We conclude that IL-15 is associated with fibrotic as well as vascular lung disease and vasculopathy in early SSc. IL-15 may contribute to the pathogenesis of SSc. IL-15 could also be a candidate biomarker for pulmonary involvement and a target for therapy in SSc.

Functional and phenotypical comparison of myofibroblasts derived from biopsies and bronchoalveolar lavage in mild asthma and scleroderma.

BACKGROUND: Activated fibroblasts, which have previously been obtained from bronchoalveolar lavage fluid (BALF), are proposed to be important cells in the fibrotic processes of asthma and scleroderma (SSc). We have studied the motility for BALF derived fibroblasts in patients with SSc that may explain the presence of these cells in the airway lumen. Furthermore, we have compared phenotypic alterations in activated fibroblasts from BALF and bronchial biopsies from patients with mild asthma and SSc that may account for the distinct fibrotic responses. METHODS: Fibroblasts were cultured from BALF and bronchial biopsies from patients with mild asthma and SSc. The motility was studied using a cell migration assay. Western Blotting was used to study the expression of alpha-smooth muscle actin (alpha-SMA), ED-A fibronectin, and serine arginine splicing factor 20 (SRp20). The protein expression pattern was analyzed to reveal potential biomarkers using two-dimensional electrophoresis (2-DE) and sequencing dual matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-TOF). The Mann-Whitney method was used to calculate statistical significance. RESULTS: Increased migration and levels of ED-A fibronectin were observed in BALF fibroblasts from both groups of patients, supported by increased expression of RhoA, Rac1, and the splicing factor SRp20. However, these observations were exclusively accompanied by increased expression of alpha-SMA in patients with mild asthma. Compared to BALF fibroblasts in mild asthma, fibroblasts in SSc displayed a differential protein expression pattern of cytoskeletal- and scavenger proteins. These identified proteins facilitate cell migration, oxidative stress, and the excessive deposition of extracellular matrix observed in patients with SSc. CONCLUSION: This study demonstrates a possible origin for fibroblasts in the airway lumen in patients with SSc and important differences between fibroblast phenotypes in mild asthma and SSc. The findings may explain the distinct fibrotic processes and highlight the motile BALF fibroblast as a potential target cell in these disorders.

Polarized subsets of human T-helper cells induce distinct patterns of chemokine production by normal and systemic sclerosis dermal fibroblasts.

The role of fibroblasts in inflammatory processes and their cross-talk with T cells is increasingly being recognized. Our aim was to explore the capacity of dermal fibroblasts to produce inflammatory chemokines potentially involved in fibrosis occurring in response to contact with polarized human T cells. Our findings indicate that the program of chemokine production by fibroblasts is differentially regulated depending on the T-helper (Th) cell subset used to activate them. Thus, Th1 and Th2 cells preferentially induced production of IFN-gamma inducible protein (IP)-10 and IL-8, respectively, whereas monocyte chemoattractant protein (MCP)-1 was equally induced by both subsets at mRNA and protein levels. Neutralization experiments indicated that membrane-associated tumour necrosis factor-alpha and IL-1 played a major role in the induction of IL-8 and MCP-1 by Th1 and Th2 cells, whereas membrane-associated IFN-gamma (present only in Th1 cells) was responsible, at least in part, for the lower IL-8 and higher IP-10 production induced by Th1 cells. The contributions of tumour necrosis factor-alpha, IL-1 and IFN-alpha were confirmed when fibroblasts were cultured separated in a semipermeable membrane from living T cells activated by CD3 cross-linking. We observed further differences when we explored signal transduction pathway usage in fibroblasts. Pharmacological inhibition of c-Jun N-terminal kinase and nuclear factor-kappaB resulted in inhibition of IL-8 mRNA transcription induced by Th1 cells but not that by Th2 cells, whereas inhibition of MEK/ERK (mitogen-activated protein kinase of extracellular signal-regulated kinase/extracellular signal-regulated kinase) and nuclear factor-kappaB resulted in inhibition of MCP-1 mRNA induced by Th2 but not by Th1 cells. Finally, no distinct differences in chemokine production were observed when the responses to T cell contact or to prototypic Th1 and Th2 cytokines were examined in systemic sclerosis versus normal fibroblasts. These findings indicate that fibroblasts have the potential to participate in shaping the inflammatory response through the activation of flexible programs of chemokine production that depend on the Th subset eliciting their response.

Small intestinal manometry in patients with systemic sclerosis.

OBJECTIVES: The study explores, by the use of manometry, the frequency and severity of small intestinal involvement in patients with systemic sclerosis, and relates the manometric findings to clinical symptoms, radiology, and some intestinal regulatory peptides. METHODS: Stationary antroduodeno-jejunal manometry was used to study small bowel involvement in 10 patients with systemic sclerosis and dysmotility of the oesophagus or signs of malabsorption. Measurements were made during fasting, after a meal, and after octreotide administration and were then compared with a sex-matched control group of healthy individuals. Plasma samples were taken in order to analyse levels of motilin, peptide YY, cholecystokinin, and somatostatin. RESULTS: Manometry was abnormal, with signs of intestinal pseudo-obstruction in eight out of 10 patients. In the control group, one individual had an abnormal manometry, as a result of burst activity. The mean contractile amplitudes during fasting and periods after food, spontaneous phase III periods, and octreotide-induced activity complexes were significantly reduced in the systemic sclerosis group when compared with controls. None of the patients, including two with advanced manometric intestinal disturbances, had small intestinal dilatation when examined by radiography. The plasma peptide levels did not differ significantly between the two groups. CONCLUSIONS: In eight out of 10 patients the manometric criteria for intestinal pseudo-obstruction were fulfilled, with a motility pattern consistent with both neuropathy and myopathy. The release of motility-regulating peptides was unaffected.

Systemic sclerosis Th2 cells inhibit collagen production by dermal fibroblasts via membrane-associated tumor necrosis factor alpha.

OBJECTIVE: In systemic sclerosis (SSc; scleroderma), T cells infiltrate organs undergoing fibrotic changes and may participate in dysregulated production of collagen by fibroblasts. The objective of this study was to functionally characterize T cells infiltrating skin lesions in early SSc and investigate their capacity to affect production of type I collagen and interstitial collagenase (matrix metalloproteinase 1 [MMP-1]) by dermal fibroblasts. METHODS: Four-color cytometric analysis was used to characterize subset distribution and production of interferon-gamma (IFN gamma) and interleukin-4 (IL-4) in T cell lines generated from the skin of patients with SSc. T cell clones were generated, and their capacity to modulate collagen and MMP-1 production by fibroblasts derived from patients with SSc and from normal individuals was assessed. Neutralizing reagents were used to identify T cell mediators involved in fibroblast modulation. RESULTS: The skin of individuals with early-stage SSc contained T cells preferentially producing high levels of IL-4. Cloned CD4+ Th2-like cells inhibited collagen production by normal fibroblasts. Th2 cell-dependent inhibition was, at least in part, contact-dependent, was essentially mediated by tumor necrosis factor alpha (TNF alpha), and was dominant over the enhancement induced by profibrotic IL-4 and transforming growth factor beta cytokines. The simultaneous induction of MMP-1 production confirmed the specificity of these observations. To be inhibitory, Th2 cells required activation by CD3 ligation. Th2 cells were less potent than were Th1 cells in inhibiting collagen production by normal fibroblasts via cell-to-cell interaction, and SSc fibroblasts were resistant to inhibition. CONCLUSION: These findings indicate that, despite their production of IL-4, Th2 cells reduce type I collagen synthesis by dermal fibroblasts because of the dominant effect of TNF alpha, and suggest that strategies based on TNF alpha blockade aimed at controlling fibrosis in SSc may be unwise.