Pulmonary Fibrosis In Systemic Sclerosis Research Articles

Pulmonary fibrosis in systemic sclerosis: Diagnosis & management

Systemic sclerosis is a fascinating, although uncommon condition. However, fibrosing alveolitis in systemic sclerosis patients is common and is associated with significant morbidity and mortality. Investigations assist, not only with diagnosis, but also with assessment of disease severity and assessment of the likelihood of disease progression, thus helping to identify those requiring closer medical supervision. Treatment of fibrosing alveolitis in systemic sclerosis is complex, as the risks of some therapies may outweigh the potential benefits, and for those with advanced disease there is a lack of donor organs available for transplantation. Great strides continue to be made in unravelling the mysteries of the immunopathogenesis of fibrosing alveolitis in systemic sclerosis, and this should eventually lead to the development of more rational and targeted pharmacological therapies.

The lung megakaryocytes and pulmonary fibrosis in systemic sclerosis

Systemic sclerosis (SSc) is an autoimmune connective tissue disease characterized by fibrotic changes in several organs including the lungs, skin, kidneys, muscles and the joints. The leading cause of death in SSc is pulmonary involvement consisting of pulmonary fibrosis with pulmonary hypertension. The pathogenesis of lung involvement in SSc is not yet clear though several mechanisms involving genetic, environmental, vascular, and immunological factors have been postulated. At the same time, the presence of megakaryocytes in the lungs is a less recognized concept and may also be contributing to lung fibrosis in SSc. These cells normally thought to be present only in the bone marrow have been demonstrated to be an important factor in the development of fibrosis of the bone marrow in the condition, idiopathic myelofibrosis. The article describes available evidence for the presence of lung megakaryocytes and hypothesizes that these cells are responsible for the development of pulmonary fibrosis in SSc based on the myelofibrosis model.

Scleroderma lung disease: evolving understanding in light of newer studies

To review therapeutic goals in pulmonary fibrosis in systemic sclerosis in the light of pathogenetic thinking and therapeutic data, with particular attention to recent data questioning the importance of the identification of alveolitis. Immunological/inflammatory activation remains the primary therapeutic target, based on recent data. Other effective therapies have not been developed, despite investigation of many pathogenetic pathways. In most cases, lung disease is predominantly fibrotic and prevention of progression is the only practicable therapeutic goal. Indications for introducing treatment remain uncertain. A granulocytosis on bronchoalveolar lavage and ground-glass attenuation on computed tomography, previously thought to denote an inflammatory histological picture ('alveolitis'), are usually indicative of fibrotic disease. By contrast, a recent staging system, integrating computed tomography and pulmonary function data, might, with refinement, identify patients likely to benefit from treatment. Treatment benefits consist of the prevention of progression and are largely confined to patients with extensive pulmonary fibrosis. Historical algorithms for the identification of alveolitis, using computed tomography and bronchoalveolar lavage, are inaccurate and do not identify patients most likely to benefit from treatment. Accurate prognostic evaluation by staging the severity of lung disease remains central to management and will be a major focus of future studies.

Membrane diffusion- and capillary blood volume measurements are not useful as screening tools for pulmonary arterial hypertension in systemic sclerosis: a case control study

BackgroundThere is no optimal screening tool for the assessment of pulmonary arterial hypertension (PAH) in patients with systemic sclerosis (SSc). A decreasing transfer factor of the lung for CO (TLCO) is associated with the development of PAH in SSc. TLCO can be partitioned into the diffusion of the alveolar capillary membrane (Dm) and the capillary blood volume (Vc). The use of the partitioned diffusion to detect PAH in SSc is not well established yet. This study evaluates whether Dm and Vc could be candidates for further study of the use for screening for PAH in SSc.MethodsEleven SSc patients with PAH (SScPAH+), 13 SSc patients without PAH (SScPAH-) and 10 healthy control subjects were included. Pulmonary function testing took place at diagnosis of PAH. TLCO was partitioned according to Roughton and Forster. As pulmonary fibrosis in SSc influences values of the (partitioned) TLCO, these were adjusted for fibrosis score as assessed on HRCT.ResultsTLCO as percentage of predicted (%) was lower in SScPAH+ than in SScPAH- (41 ± 7% vs. 63 ± 12%, p < 0.0001, respectively). Dm% in SScPAH+ was decreased as compared with SScPAH- (22 ± 6% vs. 39 ± 12%, p < 0.0001, respectively), also after adjustment for total fibrosis score (before adjustment: B = 17.5, 95% CI 9.0–25.9, p = < 0.0001; after adjustment: B = 14.3, 95% CI 6.0–21.7, p = 0.008). No difference was found in Vc%. There were no correlations between pulmonary hemodynamic parameters and Dm% in the PAH groups.ConclusionSScPAH+ patients have lower Dm% than SScPAH- patients. There are no correlations between Dm% and hemodynamic parameters of PAH in SScPAH+. These findings do not support further study of the role of partitioning TLCO in the diagnostic work- up for PAH in SSc.

Insulin-Like Growth Factor-II Is Increased in Systemic Sclerosis-Associated Pulmonary Fibrosis and Contributes to the Fibrotic Process via Jun N-Terminal Kinase- and Phosphatidylinositol-3 Kinase-Dependent Pathways

Systemic sclerosis (SSc)-related pulmonary fibrosis, for which there are few effective therapies, is the most common cause of SSc-related mortality. We examined insulin-like growth factor (IGF)-II expression in explanted lung tissues from control and SSc patients to determine its role in the pathogenesis of fibrosis. IGF-II levels in vivo were detected using immunohistochemistry. Primary lung fibroblasts were cultured from lung tissues, and IGF-II mRNA was measured using reverse transcriptase-polymerase chain reaction. Western blot analysis measured extracellular matrix (ECM) production and phosphorylated signaling molecules. Immunostaining revealed increased IGF-II expression in fibroblastic foci of SSc lungs. Furthermore, primary SSc lung fibroblasts had a fourfold increase in IGF-II mRNA and a twofold increase in IGF-II protein compared with normal lung fibroblasts. IGF-II mRNA in SSc lung fibroblasts was expressed primarily from the P3 promoter of the IGF-II gene, and IGF-II induced both a dose- and time-dependent increase in collagen type I and fibronectin production. IGF-II triggered the activation of both phosphatidylinositol-3 kinase and Jun N-terminal kinase signaling cascades, the inhibition of which diminished IGF-II-induced ECM production. Our study demonstrates increased local IGF-II expression in SSc-associated pulmonary fibrosis both in vitro and in vivo as well as IGF-II-induced ECM production through both phosphatidylinositol-3 kinase- and Jun N-terminal kinase-dependent pathways. Our results provide novel insights into the role of IGF-II in the pathogenesis of SSc-associated pulmonary fibrosis.

Cytokine concentrations in exhaled breath condensates in systemic sclerosis

Pulmonary fibrosis in systemic sclerosis (SSc) involves inflammatory processes in the lower respiratory tract. Analysis of exhaled breath condensate (EBC) is a non-invasive method for studying inflammatory mediators, such as cytokines, which are of interest from both physiological and therapeutic perspectives. The aim of this study was to assess and compare cytokine concentrations in the EBC of SSc patients and controls. EBC was collected from 19 SSc patients and 19 controls. We used a multiplex assay test kit to assay interleukin (IL)-2, -4, -6, -10, tumour necrosis factor-alpha, and interferon-gamma in samples concentrated by lyophilization. Cytokine concentrations in EBC were higher in SSc patients than in controls. The stepwise analyses showed that IL-4 was the biomarker which contributed most to the discrimination between controls and patients (Wilk's Lambda = 0.55, p < 0.001). We observed significant negative correlations of EBC cytokines with total lung capacity and diffusion capacity of the lung for carbon monoxide. These findings suggest that EBC sampling permits the non-invasive study of inflammation in SSc patients, and may be correlated with the severity of interstitial lung disease.

Elevation of IgG levels is a serological indicator for pulmonary fibrosis in systemic sclerosis with anti-topoisomerase I antibodies and those with anticentromere antibody

It is unclear whether any clinical and laboratory features are associated with pulmonary fibrosis (PF) in systemic sclerosis (SSc). We assessed these features using a database of 29 patients with SSc and anti-topoisomerase I antibodies and 68 patients with SSc and anticentromere antibody (ACA). Clinical features were not associated with the incidence of PF in patients with SSc and anti-topoisomerase I antibodies, although severe skin sclerosis was correlated with the presence of PF in patients with ACA. Serum IgG levels were often raised in patients with SSc and PF. Serum IgG levels in patients with PF were significantly higher than those in patients without PF, and were negatively correlated with percentage vital capacity and percentage diffusing capacity of the lung for carbon monoxide. In addition, serum IgG levels were correlated with serum interleukin-6. Thus, serum IgG levels are associated with PF in patients with SSc and anti-topoisomerase I antibodies and in patients with SSc and ACA.

Pulmonary fibrosis in systemic sclerosis: is treatment with cyclophosphamide more effective than placebo?

Pulmonary fibrosis in systemic sclerosis: is treatment with cyclophosphamide more effective than placebo?

Treatment of pulmonary fibrosis in systemic sclerosis: Light at the end of the tunnel?

For decades, 3 components—vascular, immunologic, and fibrotic—have characterized systemic sclerosis (SSc). The interrelationship among these components is still not well elucidated, but each has been a target of therapy. The immunologic abnormalities involve T and B lymphocytes. Early skin lesions show lymphocyte infiltration with enrichment of Th2 cells. In contrast to normal skin, early lesions in patients with the diffuse cutaneous form of SSc (dcSSc) contain T cells expressing CD4 ,CD8 / cell surface markers that produce large amounts of interleukin-4 (1). Polarization of lymphocytes is also observed in the lungs of patients with dcSSc. Presumably, such cells contribute to shaping the fibroblast phenotype of SSc, although direct evidence of their in vivo role is lacking. Autoantibodies recognizing nuclear components are found in a majority of, if not all, patients with SSc and define clinical subgroups. Autoantibodies are present early in the course of the disease, sometimes before the full-blown form develops, but they have not been shown to be directly pathogenic. They are instrumental in distinguishing between dcSSc and limited cutaneous SSc (lcSSc). The latter is more insidious by nature, is associated with anticentromere antibodies, and is more “vascular” than is the more “fibrotic” diffuse form. A recent report regarding a stimulating autoantibody to platelet-derived growth factor (PDGF) receptor (2) is of potential interest in view of the central role of PDGF and transforming growth factor (TGF ) signaling in fibrosis in SSc, but the observation needs confirmation. The antibody was present in all (!) of 46 patients and in none of the controls, but the authors did not provide details regarding clinical features. These findings, if confirmed, leave open some questions, e.g., whether the antibodies really reach target cells and whether they can stimulate lesional fibroblasts in vivo. The distinction between lcSSc and dcSSc is evident early, without clinical overlap. Features of the CREST syndrome (calcinosis, Raynaud’s phenomenon, esophageal dysmotility, sclerodactyly, telangiectasias) occur in both forms, but they differ in the extent of skin involvement. By nailfold capillaroscopy it has been shown that capillaries are both abnormal and reduced in number in both forms; neointima formation and media thickening also occur in both forms. A fundamental question remains regarding the origin of the stimulated fibroblasts. Is their abnormal function induced in situ by cytokines or other mediators, or do they constitute a new population of cells related to circulating fibrocytes, myofibroblasts, or pericytes derived from blood vessel walls? It is reasonable to assume that epithelial mesenchymal transition is involved in the process. Vascular dysfunction can now be treated with some success with angiotensin-converting enzyme inhibitors, prostacyclin derivatives, and inhibitors targeting endothelin receptors (the nonselective oral A and B receptor inhibitor bosentan and, more recently, the oral selective endothelin receptor A inhibitor sitaxsentan [3], which was approved in Europe in August 2006 for the treatment of pulmonary arterial hypertension [PAH]). These agents represent a breakthrough in the treatment of PAH in that they are associated with improved physical function; however, reduced mortality remains to be demonstrated. They are also very expensive, even compared with biologic agents such as tumor necrosis factor inhibitors. Bosentan has not been proven effective in the treatment of interstitial lung disease. The search for effective antifibrotic agents in SSc has been a source of continuing disappointment. For many years D-penicillamine was the recommended antifibrotic therapy, but the first controlled trial, published only as recently as 2004, showed no effect (4). This trial compared low-dose and high-dose treatment (150 mg Frank A. Wollheim, MD, PhD, FRCP: Lund University Hospital, Lund, Sweden. Address correspondence and reprint requests to Frank A. Wollheim, MD, PhD, FRCP, Department of Rheumatology, Lund University Hospital, Kioskgatan 3, S-221 85 Lund, Sweden. E-mail frank.wollheim@med.lu.se. Submitted for publication August 20, 2006; accepted in revised form September 29, 2006.

Pulmonary Fibrosis in Systemic Sclerosis

Pulmonary Fibrosis in Systemic Sclerosis

A multicenter, prospective, randomized, double‐blind, placebo‐controlled trial of corticosteroids and intravenous cyclophosphamide followed by oral azathioprine for the treatment of pulmonary fibrosis in scleroderma

The lack of randomized controlled trials (RCTs) in pulmonary fibrosis in systemic sclerosis (SSc) has hampered an evidence-based approach to treatment. This RCT was undertaken to investigate the effects of intravenous (IV) cyclophosphamide (CYC) followed by azathioprine (AZA) treatment in pulmonary fibrosis in SSc. Forty-five patients were randomized to receive low-dose prednisolone and 6 infusions (monthly) of CYC followed by oral AZA, or placebo. Primary outcome measures were change in percent predicted forced vital capacity (FVC) and change in single-breath diffusing capacity for carbon monoxide (DLCO). Secondary outcome measures included changes in appearance on high-resolution computed tomography and dyspnea scores. An intent-to-treat statistical analysis was performed. At baseline, there were no significant group differences in factors linked to outcome, including severity of pulmonary fibrosis and autoantibody status. Sixty-two percent of the patients completed the first year of treatment. Withdrawals included 9 patients (6 from the placebo group) with significant decline in lung function, 2 with treatment side effects (both from the active treatment group), and 6 with non-trial-related comorbidity. No hemorrhagic cystitis or bone marrow suppression was observed. Estimation of the relative treatment effect (active treatment versus placebo) adjusted for baseline FVC and treatment center revealed a favorable outcome for FVC of 4.19%; this between-group difference showed a trend toward statistical significance (P = 0.08). No improvements in DLCO or secondary outcome measures were identified. This trial did not demonstrate significant improvement in the primary or secondary end points in the active treatment group versus the group receiving placebo. However, for FVC there was a trend toward statistical significance between the 2 groups. This suggests that treatment of pulmonary fibrosis in SSc with low-dose prednisolone and IV CYC followed by AZA stabilizes lung function in a subset of patients with the disease. Therapy was well tolerated with no increase in serious adverse events.

BALF-derived fibroblasts differ from biopsy-derived fibroblasts in systemic sclerosis

Growth of fibroblasts from bronchoalveolar lavage fluid (BALF) in patients with systemic sclerosis (SSc) has previously been described. The purpose of the present study was to characterise fibroblasts from BALF and bronchial biopsies from SSc patients with alveolitis and from controls, to analyse fibroblast proliferation, migration, stress fibres and proteoglycan production. BALF and bronchial biopsies were collected from 10 patients with SSc and alveolitis and from 15 controls. Outgrowth of fibroblasts was observed from the BALF of four patients, particularly in those with a markedly increased percentage of eosinophils in BALF, but not in any member of the control group. Increased levels of granulocyte-macrophage colony-stimulating factor, correlating with the percentage of eosinophils in BALF, were found in patients when compared with controls. Fibroblasts from BALF showed an elongated, mobile phenotype and increased proteoglycan production compared to the corresponding biopsy fibroblasts. In conclusion, outgrowth of fibroblasts with an altered phenotype is reported from bronchoalveolar lavage fluid in systemic sclerosis patients with alveolitis and an increased percentage of eosinophils in the bronchoalveolar lavage fluid. These findings indicate a possible role for eosinophil-fibroblast interaction in pulmonary fibrosis in systemic sclerosis.

Oral cyclophosphamide improves pulmonary function in scleroderma patients with fibrosing alveolitis: experience in one centre

Lung involvement constitutes nowadays the major cause of morbidity and mortality in scleroderma patients. Pulmonary fibrosis in systemic sclerosis (SSc) is thought to be the consequence of interstitial inflammation. Early diagnosis and treatment of active alveolitis is essential to prevent the deterioration of pulmonary function, improving outcome in SSc patients. The aim of the study was to investigate the effect of 1-year treatment with oral cyclophosphamide (CYC) on the evolution of interstitial lung disease in scleroderma patients with a diagnosis of active alveolitis. An open-label one-arm monocenteric study was conducted on 33 scleroderma patients with active alveolitis--defined as the presence of areas of 'ground-glass attenuation' on high-resolution computed tomography and a recent deterioration in lung function-treated with oral CYC 2 mg kg-1 day-1 for 1 year and medium-low dose steroids (prednisone 25 mg for 3 months and then tapered to 5 mg/day). Results showed that diffusing capacity for carbon monoxide (DLco) values remained stable after 6 months of treatment and significantly increased after 12 months (2.06+/-1.38, 2.21+/-1.62 and 2.39+/-1.64 mmol/min/kPa, at baseline/6/12 months, respectively; p<0.001 12th month vs baseline) vital capacity (VC) values slightly increased (i.e. stabilised) in the same time frame (2.46+/-0.71, 2.41+/-0.76 and 2.56+/-0.75 l). Accordingly, the vast majority of our patients (n=29, 87.9%) presented a DLco and/or a VC improvement or stabilisation with respect to baseline. Favourable results were more likely to be observed in patients with a lower Wells' radiological grade (grade I). In 25 patients followed up for further 12 months after the interruption of therapy, VC and DLco remained stable. Thus, long-term therapy with oral CYC is effective in ameliorating and/or stabilising lung function in scleroderma patients with active alveolitis, with beneficial effects lasting up to 1 year after interruption. The higher efficacy in those patients with an early pulmonary disease stage and a lower radiological grade underlies the importance of an early diagnosis and intervention.

Serum pulmonary and activation‐regulated chemokine/CCL18 levels in patients with systemic sclerosis: A sensitive indicator of active pulmonary fibrosis

To clarify the clinical significance of serum levels of pulmonary and activation-regulated chemokine (PARC) in the diagnosis and monitoring of pulmonary fibrosis (PF) in patients with systemic sclerosis (SSc) and to compare PARC levels with KL-6 antigen or surfactant protein D (SP-D) levels. Serum PARC levels were determined by enzyme-linked immunosorbent assay in 123 SSc patients. In a retrospective longitudinal study, correlation of serum PARC levels with the activity of PF was assessed in 21 SSc patients with active PF. PARC levels at the first visit were higher in patients with SSc than in patients with systemic lupus erythematosus (SLE) or healthy controls. Increased serum PARC levels were associated with involvement of PF, decreased diffusing capacity for carbon monoxide, and decreased vital capacity in SSc patients. In the longitudinal study, serum PARC levels were significantly decreased in SSc patients with inactive PF compared with those with active PF. Elevated serum PARC levels correlated with PF and more sensitively reflected the PF activity than did serum KL-6 or SP-D levels in SSc. Serum PARC levels may be a useful new serum marker for active PF in SSc.

Augmented production of chemokines (monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1alpha (MIP-1alpha) and MIP-1beta) in patients with systemic sclerosis: MCP-1 and MIP-1alpha may be involved in the development of pulmonary fibrosis.

To determine the role of chemokines in the pathogenesis of systemic sclerosis (SSc), we examined serum levels, spontaneous production by peripheral blood mononuclear cells (PBMC), and histological distribution in the affected skin, of MCP-1, MIP-1alpha and MIP-1beta in SSc patients. Serum levels of these chemokines were examined by ELISA in 58 patients with SSc and 20 normal controls. The levels of these chemokines in culture supernatants from PBMC were also measured by ELISA. Serum levels and spontaneous production levels by PBMC of MCP-1, MIP-1alpha, and MIP-1beta were significantly elevated in patients with SSc compared with normal controls. Elevated serum levels of MCP-1 and MIP-1alpha significantly correlated with the presence of pulmonary fibrosis. MCP-1 expression in the skin of SSc was immunohistochemically examined using anti-MCP-1 MoAb. MCP-1 was strongly expressed in the epidermis, inflammatory mononuclear cells, and vascular endothelial cells in the sclerotic skin of SSc patients, but not expressed in any control skin. Furthermore, the MCP-1 expression in inflammatory mononuclear cells and endothelial cells significantly correlated with earlier onset of SSc. Thus, MCP-1, MIP-1alpha and MIP-1beta may be involved in the disease process, possibly by augmenting leucocyte migration into the affected tissues in SSc. Furthermore, MCP-1 and MIP-1alpha may play an important role in the development of pulmonary fibrosis in SSc.

B-Cell epitope mapping of DNA topoisomerase I defines epitopes strongly associated with pulmonary fibrosis in systemic sclerosis.

We hypothesized that B-cell epitope mapping of DNA Topoisomerase I (type-I topoisomerase, or Topo I) may define epitopes strongly associated with pulmonary interstitial fibrosis (PIF) in systemic sclerosis (SSc). B-cell epitope mapping of Topo I was performed using 63 20-mer peptides overlapping by eight residues and spanning the entire length of the Topo I sequence. These peptides, coupled to polystyrene pins, were tested for antibody binding by enzyme-linked immunosorbent assays (ELISAs) using immunoglobulin G fractions from anti-Topo I, anticentromere, anti-U3RNP-positive, and normal sera. Four major epitopes were recognized by anti-Topo I sera, but not from the control sera: WWEEERYPEGIKWKFLEHKG (205-224, epitope I), RIANFKIEPPGLFRGRGNHP (349-368, epitope II), PGHKWKEVRHDNKVTWLVSW (397-416, epitope III), and ELDGQEYVVEFDFLGKDSIR (517-536, epitope IV). Peptide-epitopes were then synthesized in their soluble forms and ELISA systems were developed. Epitopes II to IV are localized at highly exposed sites of the Topo I tertiary structure, whereas epitope I is localized at a less accessible site. In a cohort of 81 patients with SSc with clinical data on the evolution of their disease, patients with antibodies in their sera recognizing at least three of the four epitopes had 3.1 times (P = 0.02) the hazard of developing PIF compared with patients whose sera recognized no epitopes or only one or two of the four epitopes. The discrimination was much stronger than that achieved by the simple determination of Topo I antibodies by counterimmunoelectrophoresis and immunoblot (hazard ratio 1.7, P = 0.30) in the same patients. B-cell epitope mapping of the anti-Topo I response has identified four major epitopes which cumulatively show a strong association with the development of PIF in SSc.

Elevated Serum KL-6 Levels in Patients with Systemic Sclerosis: Association with the Severity of Pulmonary Fibrosis

Background: Serum KL-6 has been suggested to be a useful marker for the evaluation of interstitial lung disease activity. Objective: To determine the correlation between serum KL-6 levels and pulmonary fibrosis in patients with systemic sclerosis (SSc). Methods: Serum samples from patients with limited cutaneous SSc (lSSc; n = 19), diffuse cutaneous SSc (dSSc; n = 26) and normal individuals (n = 15) were examined by ELISA. Results: Serum KL-6 levels in SSc patients were significantly higher than those in normal controls. KL-6 levels in dSSc patients were significantly elevated compared with those in lSSc patients. Elevated KL-6 levels were associated with the presence of pulmonary fibrosis in SSc patients or dSSc patients. Furthermore, KL-6 levels inversely correlated with percentages of diffusion capacity of carbon monoxide and vital capacity in SSc patients or dSSc patients. Conclusion: KL-6 may be a simple, serologic indicator for the severity of pulmonary fibrosis in SSc.

Fibronectin gene polymorphisms associated with fibrosing alveolitis in systemic sclerosis.

Systemic sclerosis (SSc), a multisystem immunologic disease of unknown etiology, is commonly manifested in the lung as fibrosing alveolitis (FASSc). There is evidence to support the role of genetic factors in the predisposition to pulmonary fibrosis in SSc (HLA DR3/DR52a). This association is not complete and other candidate genes are likely involved. Of these, fibronectin is a growth factor known to play a crucial role in lung fibrosis. Our study investigated whether polymorphisms of the fibronectin gene are associated with lung fibrosis in SSc. Using the polymerase chain reaction and the restriction enzymes HaeIII, MspI, HindIII, and TaqI, we assessed the restriction fragment length polymorphisms (RFLPs) in 161 patients with SSc and 253 healthy control subjects from the United Kingdom. For each restriction enzyme, three genotypes were possible corresponding to the presence of the cutting site on neither, one, or both chromosomes (HaeIII AA, AB, BB; MspI CC, CD, DD; HindIII EE, EF, FF; TaqI GG, GH, HH). There was a significant decrease of genotype BB (FASSc: 17%, control: 34%; Pcorr = 0.006) with a reciprocal increase of genotype AB (FASSc: 62%, control: 46%; Pcorr = 0.022) in FASSc with the HaeIII RFLP. A significant decrease of genotype DD was observed in FASSc (FASSc: 28%, control: 41%; Pcorr = 0.038) with the MspI RFLP. The coassociation of genotypes AB (HaeIII RFLP) and CD (MspI RFLP) was present in 45% of the FASSc group (P = 0.0059), with an increased relative risk of developing fibrosing alveolitis of 1.988. We conclude that genotypes of the fibronectin gene are useful prognostic factors in SSc, helping to predict individuals likely to develop pulmonary fibrosis.

Cytokine concentrations in bronchoalveolar lavage fluid of patients with systemic sclerosis

The pathophysiology of pulmonary fibrosis in patients with systemic sclerosis (SSc) is poorly understood, but a number of recent studies have demonstrated an inflammatory process involving the lower respiratory tract. The objective of the present study was to determine the concentrations of several cytokines in the bronchoalveolar lavage (BAL) fluid of patients with SSc and to assess whether the enhanced expression of certain cytokines is associated with the presence of alveolitis. BAL was performed on patients with SSc (with or without alveolitis) and on normal control subjects. Lyophilized BAL fluid samples were assayed by enzyme-linked immunosorbent assay for tumor necrosis factor alpha (TNF alpha), interleukin-1alpha (IL-1alpha), IL-4, IL-6, IL-8, macrophage inflammatory protein 1alpha (MIP-1alpha), and RANTES. There were significant differences between groups in the BAL fluid concentrations of TNF alpha (P = 0.0005, with levels in SSc patients with alveolitis higher than those in normal controls), IL-8 (P = 0.006, with levels in both SSc groups higher than those in normal controls), MIP-1alpha (P = 0.009, with levels in SSc patients with alveolitis higher than those in SSc patients without alveolitis and than those in normal controls), and RANTES (P = 0.03, with levels in SSc patients without alveolitis higher than those in normal controls). With the exception of RANTES, the highest levels were detected in SSc patients with alveolitis. Each of these cytokines, either alone or in combination, may play an important role in the pathogenesis of pulmonary fibrosis in SSc.

Elevated levels of eosinophil major basic protein in the sera of patients with systemic sclerosis.

To examine eosinophil activation, as reflected by evidence of eosinophil degranulation in the blood and affected tissues, in patients with diffuse and limited cutaneous forms of systemic sclerosis (SSc). Levels of the eosinophil-derived major basic protein (MBP), a marker of eosinophil degranulation, were determined in sera from 46 SSc patients, from patients with rheumatoid arthritis and giant cell arteritis, and from healthy volunteers, and in bronchoalveolar lavage fluid from 4 SSc patients. Extracellular tissue deposition of MBP was evaluated in biopsy specimens from affected skin or lung of 11 SSc patients. Patients with diffuse cutaneous SSc (dcSSc) had elevated serum MBP levels compared with normal individuals (mean +/- SD 762 +/- 271 ng/ml versus 534 +/- 144 ng/ml; P = 0.0004). MBP levels were positively correlated with the extent of cutaneous involvement, and negatively correlated with pulmonary function and duration of disease (r = -0.20). By immunohistochemical analysis, modest extracellular MBP deposition could be demonstrated in involved skin in 7 of 10 biopsy specimens, and MBP staining was prominent in affected lung tissues in 2 patients. Eosinophil degranulation appears to be increased in some patients with dcSSc, as indicated by elevated serum levels of MBP and extracellular accumulation of MBP in the lung. Eosinophil granule proteins may contribute to the development of cutaneous and pulmonary fibrosis in SSc.