High-dose immunosuppressive therapy for severe systemic sclerosis: initial outcomes

Systemic sclerosis (SSc) is a multisystem disease of presumed autoimmune pathogenesis for which no proven effective treatment exists. High-dose immunosuppressive therapy (HDIT) has been proposed as an investigational treatment for severe autoimmune diseases. Nineteen patients with poor-prognosis SSc underwent HDIT. The median age was 40 years (range, 23-61 years), the median modified Rodnan skin score (a measure of dermal sclerosis) was 31, and the median DLCO was 57%. Conditioning therapy involved 800 cGy total body irradiation (TBI) (+/- lung shielding to approximately 200 cGy), 120 mg/kg cyclophosphamide, and 90 mg/kg equine antithymocyte globulin. CD34-selected granulocyte-colony-stimulating factor-mobilized autologous blood stem cells provided hematopoietic rescue. With median follow-up at 14.7 months, the Kaplan-Meier estimated 2-year survival rate was 79%. Three patients died of treatment complications and one of disease progression. Two of the first 8 patients had fatal regimen-related pulmonary injury, a complication not found among 11 subsequent patients who received lung shielding for TBI. Overall, internal organ functions were stable to slightly worse after HDIT, and 4 patients had progressive or nonresponsive disease. As measured by modified Rodnan skin scores and modified health assessment questionnaire disability index (mHAQ-DI) scores, significant disease responses occurred in 12 of 12 patients evaluated at 1 year after HDIT. In conclusion, though important treatment-related toxicities occurred after HDIT for SSc, modifications of initial approaches appear to reduce treatment risks. Responses in skin and mHAQ-DI scores exceed those reported with other therapies, suggesting that HDIT is a promising new therapy for SSc that should be evaluated in prospective randomized studies.     

Myofibroblasts and hyalinized collagen as markers of skin disease in systemic sclerosis

OBJECTIVE: To investigate the correlation between the degree of dermal fibrosis and myofibroblast infiltration using clinical assessments of skin thickness and hardness in systemic sclerosis (SSc). METHODS: Eleven patients with diffuse SSc and 10 healthy controls were evaluated using the modified Rodnan skin thickness score and durometry (hardness measurement). Biopsy samples were obtained from the dorsal mid-forearm in all subjects at the baseline visit and again 6-12 months later in patients with SSc. Five of the patients with SSc received treatment with cyclophosphamide (CYC) in the interval between skin biopsies. Biopsy sections were assessed for myofibroblast and hyalinized collagen content by 2 blinded observers. RESULTS: Myofibroblast and hyalinized collagen scores each correlated with the forearm skin score (r = 0.83, P < 0.0001 and r = 0.78, P < 0.0001, respectively) and with the forearm durometry score (r = 0.72, P < 0.0004 and r = 0.69, P < 0.0008, respectively). The change in the dermal hyalinized collagen score correlated with the change in the forearm durometry score (r = 0.74, P < 0.0213). The myofibroblast score decreased in all 5 patients who received CYC and increased in those receiving non-CYC treatments (P < 0.01 for the difference). CONCLUSION: Myofibroblasts play an important role in the pathogenesis of fibrosis, and our data imply that quantification of myofibroblasts and hyalinized collagen in skin may be a useful outcome measure in clinical studies of SSc.     

Allogeneic marrow transplantation in patients with severe systemic sclerosis: resolution of dermal fibrosis

OBJECTIVE: To evaluate the safety and efficacy of allogeneic hematopoietic cell transplantation (HCT) after myeloablative conditioning in patients with severe systemic sclerosis (SSc). METHODS: Eligibility criteria for the study included SSc patients with features indicative of a poor prognosis. The myeloablative conditioning regimen included busulfan, cyclophosphamide, and antithymocyte globulin. Prophylaxis for graft-versus-host disease (GVHD) consisted of cyclosporine and methotrexate. Bone marrow was transplanted from HLA-identical siblings. RESULTS: Two patients with diffuse cutaneous SSc and lung involvement who were refractory to conventional immunosuppressive treatment were enrolled in the study. In patient 1, there were no complications related to the conditioning regimen, and GVHD did not develop after transplantation. At 5 years after HCT, there was nearly complete resolution of the scleroderma and marked improvement in physical functioning. Internal organ function improved (lung) or remained stable. On examination of serial skin biopsy samples, there was resolution of the dermal fibrosis. Patient 2 experienced skin toxicity from the conditioning regimen and hypertensive crisis that was likely related to high-dose corticosteroids given for treatment of GVHD. Although this patient experienced an improvement in scleroderma and overall functioning, a fatal opportunistic infection developed 17 months after HCT. CONCLUSION: Allogeneic HCT may result in sustained remission of SSc. GVHD and opportunistic infections are the major risks associated with allogeneic HCT for SSc, as for allogeneic HCT in general.     

Skin involvement in scleroderma--where histological and clinical scores meet

OBJECTIVES: A clinico-pathological study in diffuse systemic sclerosis (SSc) patients was performed to analyse whether the skin histological organization and the pro-fibrotic signals elicited by TGF-beta in fibroblasts vary according to the modified Rodnan skin score (mRSS). METHODS: Twenty-seven SSc patients underwent 45 skin biopsies with simultaneous measure of mRSS before or after treatment by immunosuppressive drugs, with or without autologous peripheral haematopoietic stem cell transplantation (HSCT). RESULTS: Double-blind optic microscopy analysis of the biopsies standard extracellular matrix stains allowed to define three histological subgroups: 6 with grade 1 weak fibrosis, 30 with grade 2 moderate fibrosis and 9 with grade 3 severe fibrosis. A significant (P < 0.0001) was identified between the grades of fibrosis and the mRSS. In skin fibroblast cultures, Smad3 phosphorylation levels, as well as mRNA steady-state levels of two transforming growth factor (TGF)-beta/Smad3 targets, COL1A2 and PAI-1, increased in parallel with the mRSS. When compared with pre-transplant values the degree of fibrosis observed after HSCT in the papillary and in the reticular dermis decreased in parallel with the fall in mRSS (n = 5 consecutive patients with repeated biopsies). CONCLUSIONS: The histological extent of skin fibrosis correlates closely with the mRSS. Both parameters appeared to regress after HSCT. The extent of TGF-beta signalling activation in SSc skin fibroblasts appears to parallel the severity of disease.     

Tyrosine Kinase Inhibitors in the Treatment of Systemic Sclerosis: From Animal Models to Clinical Trials

Efficient antifibrotic therapies are not available for patients with systemic sclerosis (SSc). This review summarizes the current preclinical and clinical evidence for imatinib and related tyrosine kinase inhibitors as potential antifibrotic therapies for SSc and other fibrotic diseases. In experimental models of SSc, imatinib, nilotinib, and dasatinib demonstrated strong antifibrotic effects. Imatinib not only prevented fibrosis in the bleomycin-induced model of dermal fibrosis and the tight skin mouse-1 model but also reduced established fibrosis in a modified bleomycin model. Open-label, proof-of-concept trials in SSc showed moderate effects on skin fibrosis, biological measures of skin fibrosis, and lung fibrosis compared with baseline measures. However, whether this reflects the natural course of the disease or is a result of treatment effects is unclear and needs to be analyzed in larger, multicenter, randomized, placebo-controlled trials. Toxicity is expected from cancer trials with frequent mild to moderate adverse events.     

Interleukin‐13–producing CD8+ T cells mediate dermal fibrosis in patients with systemic sclerosis

Objective

Fibrosis is a major contributor to morbidity and mortality in systemic sclerosis (SSc). T cells are the predominant inflammatory infiltrate in affected tissue and are thought to produce cytokines that drive the synthesis of extracellular matrix (ECM) proteins by fibroblasts, resulting in excessive fibrosis. We have previously shown that aberrant interleukin‐13 (IL‐13) production by peripheral blood effector CD8+ T cells from SSc patients correlates with the extent of skin fibrosis. The present study was undertaken to investigate the role of IL‐13 production by CD8+ T cells in dermal fibrosis, an early and specific manifestation of SSc.

Methods

ECM protein production by normal dermal fibroblasts cocultured with SSc CD8+ T cell supernatants was determined by quantitative polymerase chain reaction and Western blotting. Skin‐homing receptor expression and IL‐13 production by CD8+ T cells in the peripheral blood of SSc patients were measured by flow cytometry. IL‐13+ and CD8+ cells in sclerotic skin were identified by immunohistochemistry.

Results

IL‐13–producing circulating CD8+ T cells from patients with SSc expressed skin‐homing receptors and induced a profibrotic phenotype in normal dermal fibroblasts, which was inhibited by an anti–IL‐13 antibody. High numbers of CD8+ T cells and IL‐13+ cells were found in the skin lesions of SSc patients, particularly during the early inflammatory phase of the disease.

Conclusion

These findings show that IL‐13–producing CD8+ T cells are directly involved in modulating dermal fibrosis in SSc. The demonstration that CD8+ T cells homing to the skin early in the course of SSc are associated with accumulation of IL‐13 is an important mechanistic contribution to the understanding of the pathogenesis of dermal fibrosis in SSc and may represent a potential target for therapeutic intervention.

     

High-dose immunosuppressive therapy and autologous peripheral blood stem cell transplantation for severe multiple sclerosis

There were 26 patients enrolled in a pilot study of high-dose immunosuppressive therapy (HDIT) for severe multiple sclerosis (MS). Median baseline expanded disability status scale (EDSS) was 7.0 (range, 5.0-8.0). HDIT consisted of total body irradiation, cyclophosphamide, and antithymocyte globulin (ATG) and was followed by transplantation of autologous, granulocyte colony-stimulating factor (G-CSF)-mobilized CD34-selected stem cells. Regimen-related toxicities were mild. Because of bladder dysfunction, there were 8 infectious events of the lower urinary tract. One patient died from Epstein-Barr virus (EBV)-related posttransplantation lymphoproliferative disorder (PTLD) associated with a change from horse-derived to rabbit-derived ATG in the HDIT regimen. An engraftment syndrome characterized by noninfectious fever with or without rash developed in 13 of the first 18 patients and was associated in some cases with transient worsening of neurologic symptoms. There were 2 significant adverse neurologic events that occurred, including a flare of MS during mobilization and an episode of irreversible neurologic deterioration after HDIT associated with fever. With a median follow-up of 24 (range, 3-36) months, the Kaplan-Meier estimate of progression (>/= 1.0 point EDSS) at 3 years was 27%. Of 12 patients who had oligoclonal bands in the cerebrospinal fluid at baseline, 9 had persistence after HDIT. After HDIT, 4 patients developed new enhancing lesions on magnetic resonance imaging of the brain. The estimate of survival at 3 years was 91%. Important clinical issues in the use of HDIT and stem cell transplantation for MS were identified; however, modifications of the initial approaches appear to reduce treatment risks. This was a heterogeneous high-risk group, and a phase 3 study is planned to fully assess efficacy.     

Foot involvement in systemic sclerosis: a longitudinal study of 100 patients

OBJECTIVE: To investigate the clinical and radiologic features of foot involvement in systemic sclerosis (SSc). PATIENTS: One hundred patients (91 women, 9 men; mean age, 51.9 +/- 11 years) with SSc (mean disease duration, 17.4 +/- 10.5 years) were retrospectively studied. Seventy-four subjects had limited scleroderma and 26 diffuse scleroderma. METHODS: Radiologic changes of foot involvement were assessed at presentation (time of diagnosis) and follow-up ranging from 1 to 28 years (median range, 7 years) and were compared with changes detected in the hands of each patient at the same presentation and follow-up. Correlations with skin and internal organ involvement were assessed. RESULTS: Ninety patients had foot involvement clinically. Forty-three had it at initial evaluation; 47 developed it during follow-up. Median time to clinical event occurrence was 10 years (95% CI, 6.7-13.3) with 44% censored case probability at this time. The onset of clinically evident foot involvement was later in limited SSc than in diffuse SSc. In comparison with hands with SSc, feet with SSc had lower rates of necrotizing Raynaud's phenomenon and tendon friction rubs and decreased skin thickening scores, whereas arthralgias occurred significantly more often. At presentation, 37 patients had radiologic abnormalities of their feet compared with 69 of their hands (P <.001); the hands had a significantly higher prevalence of acroosteolysis (P <.001). At the end of the follow-up, 35 of 50 SSc patients had radiographic foot involvement compared with 50 of 51 with hand involvement (P <.001). A significantly higher prevalence of acroosteolysis (P <.001), calcinosis (P <.05), and erosions (P <.05) of the hands were detected at that time. CONCLUSION: This study shows that compared with hand involvement in SSc, foot involvement in SSc has a later onset and is relatively less frequent but can be disabling.     

Upregulated expression of transforming growth factor-beta receptors in dermal fibroblasts of skin sections from patients with systemic sclerosis

OBJECTIVE: To investigate the expression levels of transforming growth factor-beta (TGF-beta) receptors in the skin of patients with systemic sclerosis (SSc). METHOD: We examined expressions of TGF-beta type I and type II receptors (TGF-betaRI and TGF-betaRII) in skin sections of 5 patients with SSc and 5 healthy controls using in situ hybridization and immunohistochemical analysis. RESULTS: The expression levels of both TGF-betaRI and TGF-betaRII were elevated in the dermal fibroblasts of skin sections from patients with SSc in comparison to control skin sections in in situ hybridization and in immunohistochemical stainings. The numbers of fibroblasts expressing TGF-betaRI and TGF-betaRII in the SSc skin sections were increased in comparison to controls. The inflammatory cells around the vessels also expressed TGF-betaRI and TGF-betaRII intensively in the SSc skin sections. CONCLUSION: These results suggest that the autocrine TGF-beta signaling due to the overexpression of TGF-betaRI and TGF-betaRII in dermal fibroblasts is involved in the pathogenesis of dermal fibrosis in patients with SSc.     

Seventeen-point dermal ultrasound scoring system--a reliable measure of skin thickness in patients with systemic sclerosis

OBJECTIVE: Our objective was to develop a 17-site ultrasound method of measuring skin thickness in patients with systemic sclerosis (SSc) and to assess its inter- and intra-observer variability. METHODS: Dermal thickness (using a 22 MHz ultrasound probe) was measured at 17 sites (corresponding to those assessed in the modified Rodnan skin score) in 39 patients with SSc (26 limited cutaneous, 13 diffuse) and 34 healthy controls. The sum of the thicknesses (at the 17 sites) and the maximal thickness were also documented. Because skin thickness varies between sites, each measurement was converted to a z-score. Inter- and intra-observer variability were assessed in 35 patients/33 controls, and 20 patients/15 controls respectively. RESULTS: Measurement precision was good for the dermal measurements-intraclass correlation coefficients at the 17 sites ranged from 0.65 to 0.94 for the inter-observer variability (0.86 for maximum thickness) and from 0.55 to 0.96 for the intra-observer variability (0.92 for maximum thickness). CONCLUSION: Our results suggest that the 17-point dermal ultrasound scoring system is extremely reliable and may therefore be a useful measure of outcome, including in clinical trials.     

Cartilage oligomeric matrix protein expression in systemic sclerosis reveals heterogeneity of dermal fibroblast responses to transforming growth factor beta

OBJECTIVE: Cartilage oligomeric matrix protein (COMP) accumulates in systemic sclerosis (SSc) skin and is upregulated by transforming growth factor (TGF)beta. To further characterise the response to TGFbeta in SSc, we investigated TGFbeta1 and COMP expression and myofibroblast staining in SSc skin. METHODS: Skin biopsies from patients with diffuse cutaneous SSc (dSSc), limited cutaneous SSc (lSSc) and healthy controls were evaluated for COMP mRNA expression using real-time PCR. COMP, alpha-smooth muscle actin (SMA) and TGFbeta were assessed in skin sections and in cultured fibroblasts by immunohistochemistry. Clinical disease status was assessed by the modified Rodnan skin score (mRSS). RESULTS: Myofibroblasts expressing SMA and COMP were found coexpressed in many cells in dSSc dermis, but each also stained distinct cells in the dermis. Cultured SSc dermal fibroblasts also showed heterogeneity for COMP and SMA expression, with cells expressing SMA, COMP, both or neither. TGFbeta treatment increased COMP and SMA-expressing cells. COMP mRNA expression in lesional skin from patients with dSSc correlated with the mRSS and TGFbeta1 staining. CONCLUSION: These findings suggest that TGFbeta upregulation of COMP and/or SMA expression in subpopulations of fibroblasts contributes to different pathways of fibrosis and that multiple TGFbeta regulated genes may serve as biomarkers for the degree of SSc skin involvement.     

Results of autologous and allogeneic hematopoietic cell transplant therapy for multiple myeloma

We compared the results of autologous and allogeneic peripheral blood hematopoietic cell transplant (HCT) in 87 patients with multiple myeloma using myeloablative preparative regimen. Autologous transplant (n=70) led to a lower 100-day transplant-related mortality (TRM) of 4% [0-9%] compared to 18% [0-36%] in allogeneic recipients (P=0.02). More frequent complete responses were seen in allogeneic recipients (64% [37-91%] vs 34% [23-45%] in autologous recipients, P=0.09). In autologous recipients, survival at 1 year was 86% [80-95%] and, it fell to 50% [47-75%] at 4 years, whereas in allogeneic recipients, survival at 1 and 4 years remained at 64% [40-87%]. In patients surviving more than one year, 4-year survival was superior in allogeneic (100%) vs autologous recipients (58% [41-75%], P=0.02). A trend toward higher relapse was seen in autologous transplant patients (73% [55-90%] vs 37% [11-63%] in allogeneic transplant patients, P=0.1). We observed good tolerance of myeloablative conditioning regimen followed by either autologous or allogeneic transplant. Although autologous HCT is associated with lower TRM, allogeneic HCT has acceptable TRM, and is more likely to provide a sustained response. Allogeneic HCT may be suitable in younger patients, soon after diagnosis, and in those with chemosensitive disease.     

Pathology and pathogenesis of portal venopathy in idiopathic portal hypertension: Hints from systemic sclerosis

Idiopathic portal hypertension (IPH) is a non-cirrhotic presinuosidal portal hypertension of unknown etiology. Stenosis of smaller portal veins with portal fibrosis is a pathologic hallmark of IPH. Association of systemic sclerosis (SSc) with IPH is recognized, and similar pathologic features are reported in small portal tracts and skin of IPH and SSc, respectively. In addition, levels of transforming growth factor-β (TGF-β) and connective tissue growth factor are elevated in serum and in affected skin and portal tracts of these two diseases, suggesting that IPH share fibrogenetic mechanisms with SSc. Endothelial to mesenchymal transition (EndMT) of microvasculatures of skin could be responsible for dermal fibrosis in SSc. In IPH, EndMT of portal vein endothelium via TGF-β/Smad activation may also be involved in small portal venpathy. In IPH, enhanced expression of pSmad2 in venous endothelium of smaller portal veins was associated with reduced CD34 expression. CD34 and S100A4, and CD34 and type I collagen were colocalized to portal vein endothelium in IPH. Such myofibroblastic phenotypes may be responsible for periportal-venous deposition of collagen and compressive portal venous obliteration. These small portal venous lesions may in turn lead to portal venous insufficiency followed by subcapsular atrophy in IPH.     

A modified model of graft-versus-host-induced systemic sclerosis (scleroderma) exhibits all major aspects of the human disease

OBJECTIVE: Diffuse systemic sclerosis (SSc; scleroderma) is a debilitating disease characterized by excessive dermal fibrosis with later progression to internal organs. In addition to the fibrotic component, major aspects of the disease include vascular or circulatory involvement and immune dysregulation evidenced by inflammatory cells in affected tissues and production of autoantibodies. Many animal models resembling this disease have been studied, including genetic models in mice and chickens, challenge with chemicals such as bleomycin or vinyl chloride to induce fibrosis, and models of graft-versus-host (GVH)-induced disease using certain strains of mice with differences in minor histocompatibility loci. The present studies were undertaken to determine if alteration of the induction of GVH-induced scleroderma could result in a model that more fully represented the human condition. METHODS: Disease was induced by injection of spleen cells from B10.D2 mice into BALB/c mice deficient in mature T and B cells (recombination-activating gene 2 targeted). Dermal thickening, collagen deposition, vasoconstriction, and parameters of immunity were analyzed. RESULTS: Similar to the human disease, this modified GVH model of SSc demonstrated evidence of dermal thickening, particularly in the extremities, progressive fibrosis of internal organs, vasoconstriction and altered expression of vascularity markers in skin and internal organs, early immune activation, inflammation in skin and internal organs, and autoantibody generation. CONCLUSION: This modified model of GVH-induced SSc exhibits all major components of human disease and is likely to contribute to better understanding of the disease mechanisms and, ultimately, improved treatments for patients.     

Autologous bone marrow transplantation in the treatment of refractory systemic sclerosis: early results from a French multicentre phase I-II study

Haematopoietic stem cell transplantation (HSCT) has been proposed for refractory autoimmune diseases, including systemic sclerosis (SSc). A sequential Bayesian phase I-II clinical trial was conducted in SSc patients to assess the feasibility, the tolerance and the efficacy of autologous HSCT. Peripheral blood stem cells (PBSC) were collected using cyclophosphamide (4 g/m2) and recombinant human granulocyte colony-stimulating factor (5 micro g/kg/d) and reinfused after positive CD34+ selection. Conditioning used cyclophosphamide (200 mg/kg) or melphalan (140 mg/m2) according to cardiac function. The main end-point was the failure of the procedure, defined by failure of either PBSC mobilization, CD34+ selection or intensification procedure, or by procedure-related death. Among the 12 enrolled patients, three failures occurred: one PBSC mobilization, one CD34+ selection and one CD34+ intensification. Probability of graft failure was estimated at 0.286 (95% confidence interval: 0.095-0.54). Autologous PBSC (n = 10) or bone marrow (n = 1) transplantation was actually performed in 11 patients with one procedure-related death. Median time to neutrophil (> 0.5 x 10(9)/l) and platelet (> 25 x 10(9)/l) haematopoietic reconstitution was 12 and 10 d respectively. After 18 months (range 1-26), eight out of 11 patients have shown major or partial response. Non-myeloablative conditioning, followed by a T cell-depleted autologous PBSC or bone marrow transplantation, appears feasible with low toxicity in severe SSc with short-term clinical benefits.     

Decreased susceptibility to Fas-induced apoptosis of systemic sclerosis dermal fibroblasts

OBJECTIVE: To determine whether dysregulated apoptosis of systemic sclerosis (SSc) fibroblasts contributes to progressive fibrosis by promoting fibroblast longevity. METHODS: We examined the pattern of fibroblast proliferation and apoptosis in SSc skin lesions and the susceptibility of cultured SSc dermal fibroblasts to apoptosis. Skin biopsy samples from SSc patients and control subjects were used to establish fibroblast cultures and were examined histologically. In skin sections, apoptosis was examined by TUNEL, and proliferation by immunostaining for proliferating cell nuclear antigen. Susceptibility of fibroblasts to apoptosis induced in vitro by different stimuli was studied by TUNEL. Expression of Bcl-2, Bcl-x, and Bax proteins in cultured fibroblasts was studied by Western blotting. RESULTS: Proliferation of dermal fibroblasts was not observed in normal skin but was present in skin from patients with SSc and other inflammatory skin diseases. Apoptosis of fibroblasts in SSc fibrotic skin lesions was not observed. In vitro, SSc fibroblasts were specifically resistant to apoptosis induced by Fas receptor stimulation but had normal susceptibility to apoptosis induced by nonspecific stimuli (protein kinase inhibition or serum withdrawal). Decreased susceptibility to Fas stimulation was not caused by decreased levels of surface Fas receptor. In SSc fibroblasts, quiescence induced by confluence and serum starvation was followed by an abnormal down-regulation of proapoptotic Bax protein. Up-regulation of the Bax:Bcl-2 ratio in SSc fibroblasts by Bcl-2 antisense oligonucleotides restored their susceptibility to Fas-mediated apoptosis. CONCLUSION: Our findings suggest that abnormal apoptotic regulation in fibroblasts can contribute to the pathogenesis of progressive fibrosis in SSc. Modulation of Bcl-2-related proteins appears to be a potential target for the development of apoptosis-based antifibrotic strategies.     

High frequency ultrasound assessment of skin in systemic sclerosis patients

Aim of the workTo evaluate the role of high frequency ultrasound (HFU) in assessing skin changes in terms of thickness and echogenicity in systemic sclerosis (SSc) patients with early and late changes.Patients and methodsTwenty-three SSc patients were enrolled along with 21 matched controls. Skin thickness was assessed using modified Rodnan skin score (mRSS) and HFU.ResultsPatients had mean age of 41.8 ± 9.1 years, 91.3% were females, mean disease duration 6.0 ± 4.6 years, 11 patients had early (<5 years) and 12 late (≥5 years) disease, 8 patients had limited (lcSSc) and 15 diffuse (dcSSc) cutaneous SSc. Antinuclear antibody was positive in 17 (73.9%) and antiscleroderma-17 in 18 (78.3%). Patients had significantly thicker skin between second and third metacarpophalangeal joint (L = 1.52 ± 0.35 mm vs 1.25 ± 0.35 mm; p = 0.017 and T = 1.48 ± 0.34 mm vs 1.26 ± 0.33 mm; p = 0.038 respectively). Patients with early disease had thicker skin than those with late disease. HFU dermal thickness showed no significant difference according to gender, subtypes, presence and absence of clinical manifestations or autoantibody positivity. There was significant higher dermal thickness in patients with reflux (p = 0.009) and was lower in patients with interstitial pulmonary fibrosis (p < 0.05). There was negative correlation between US dermal thickness and disease duration (p < 0.05). mRSS showed no correlation with HFU dermal thickness in all areas.ConclusionHFU is useful in assessing skin pathologic changes (even subclinical changes) in terms of thickness and echogenicity in SSc patients. Moreover, it could be a potential screening tool in differentiating normal from pathologic skin thickness.     

Treatment with imatinib prevents fibrosis in different preclinical models of systemic sclerosis and induces regression of established fibrosis

Objective

Imatinib is a small‐molecule tyrosine kinase inhibitor capable of selective, dual inhibition of the transforming growth factor β and platelet‐derived growth factor (PDGF) pathways. Imatinib has previously been shown to prevent the development of inflammation‐driven experimental fibrosis when treatment was initiated before administration of the profibrotic stimulus. The aim of this study was to confirm the efficacy of imatinib in a murine model of systemic sclerosis (SSc) that is less driven by inflammation and to investigate whether imatinib is also effective for the treatment of established fibrosis.

Methods

The tight skin 1 (TSK‐1) mouse model of SSc was used to evaluate the antifibrotic effects of imatinib in a genetic model of the later stages of SSc. In addition, the efficacy of imatinib for the treatment of preestablished fibrosis was analyzed in a modified model of bleomycin‐induced dermal fibrosis in which the application of bleomycin was prolonged and the onset of treatment was late.

Results

Treatment with imatinib reduced dermal and hypodermal thickening in TSK‐1 mice and prevented the differentiation of resting fibroblasts into myofibroblasts. In the model of preestablished dermal fibrosis, imatinib not only stopped further progression of fibrosis but also induced regression of preexisting dermal fibrosis, with a reduction in dermal thickness below pretreatment levels.

Conclusion

These results indicate that combined inhibition of the tyrosine kinase c‐Abl and PDGF receptor might be effective in the later, less inflammatory stages of SSc and for the treatment of established fibrosis. Thus, imatinib might be an interesting candidate for clinical trials in patients with longstanding disease and preexisting tissue fibrosis.

     

Mutant fibrillin 1 from tight skin mice increases extracellular matrix incorporation of microfibril-associated glycoprotein 2 and type I collagen

OBJECTIVE: Skin fibrosis in the TSK mouse, a model of skin fibrosis seen in systemic sclerosis (SSc), is caused by a large in-frame duplication in the Fbn1 gene, tsk-Fbn1. We investigated whether tsk-Fbn1 might cause dermal fibrosis by affecting Fbn1 and associated extracellular matrices. We also studied whether deposition of microfibril-associated glycoprotein 2 (MAGP-2), a protein that is associated with fibrillin 1, was altered in the skin of patients with SSc. METHODS: An in vitro model of the TSK mouse was created by conditionally expressing tsk-Fbn1 in mouse embryonic fibroblasts (MEFs). Cell cultures were examined by immunofluorescence and Western and Northern blotting to determine the effect of tsk-Fbn1 on the structure, expression, and deposition of fibrillin 1 (Fbn-1), type I collagen, and MAGP-2. The skin of TSK mice and SSc patients was analyzed by immunohistochemistry for MAGP-2 expression. RESULTS: Expression of tsk-Fbn1 in cultured MEF cells altered the morphology of Fbn-1 fibers and increased the deposition of type I collagen into the extracellular matrix (ECM) without concomitantly changing messenger RNA expression, secretion, or processing of type I procollagen. Moreover, MEF cells expressing tsk-Fbn1 showed increased MAGP-2 matrix. MAGP-2 was increased in the dermis of TSK mice. Fibrotic SSc skin also showed higher levels of MAGP-2 in the dermis than nonfibrotic SSc skin and normal skin. CONCLUSION: Tsk-Fbn1 altered ECM organization and caused fibrosis by affecting the deposition of MAGP-2 or other Fbn-1-associated proteins. Alterations in microfibril structure or deposition might contribute to fibrosis in SSc.