Treatment of systemic sclerosis with gamma-interferon

RAGE and TGF-β1 Cross-Talk Regulate Extracellular Matrix Turnover and Cytokine Synthesis in AGEs Exposed Fibroblast Cells

AGEs accumulation in the skin affects extracellular matrix (ECM) turnover and triggers diabetes associated skin conditions and accelerated skin aging. The receptor of AGEs (RAGE) has an essential contribution to cellular dysfunction driven by chronic inflammatory responses while TGF-β1 is critical in both dermal homeostasis and inflammation. We investigated the contribution of RAGE and TGF-β1 to the modulation of inflammatory response and ECM turnover in AGEs milieu, using a normal fibroblast cell line. RAGE, TGF-β1, collagen I and III gene and protein expression were upregulated after exposure to AGEs-BSA, and MMP-2 was activated. AGEs-RAGE was pivotal in NF-κB dependent collagen I expression and joined with TGF-β1 to stimulate collagen III expression, probably via ERK1/2 signaling. AGEs-RAGE axis induced upregulation of TGF-β1, TNF-α and IL-8 cytokines. TNF-α and IL-8 were subjected to TGF-β1 negative regulation. RAGE’s proinflammatory signaling also antagonized AGEs-TGF-β1 induced fibroblast contraction, suggesting the existence of an inhibitory cross-talk mechanism between TGF-β1 and RAGE signaling. RAGE and TGF-β1 stimulated anti-inflammatory cytokines IL-2 and IL-4 expression. GM-CSF and IL-6 expression appeared to be dependent only on TGF-β1 signaling. Our data also indicated that IFN-γ upregulated in AGEs-BSA milieu in a RAGE and TGF-β1 independent mechanism. Our findings raise the possibility that RAGE and TGF-β1 are both involved in fibrosis development in a complex cross-talk mechanism, while also acting on their own individual targets. This study contributes to the understanding of impaired wound healing associated with diabetes complications.

Pulmonary vaccination as a novel treatment for lung fibrosis

Pulmonary fibrosis is an untreatable, uniformly fatal disease of unclear etiology that is the result of unremitting chronic inflammation. Recent studies have implicated bone marrow derived fibrocytes and M2 macrophages as playing key roles in propagating fibrosis. While the disease process is characterized by the accumulation of lymphocytes in the lung parenchyma and alveolar space, their role remains unclear. In this report we definitively demonstrate the ability of T cells to regulate lung inflammation leading to fibrosis. Specifically we demonstrate the ability of intranasal vaccinia vaccination to inhibit M2 macrophage generation and fibrocyte recruitment and hence the accumulation of collagen and death due to pulmonary failure. Mechanistically, we demonstrate the ability of lung Th1 cells to prevent fibrosis as vaccinia failed to prevent disease in Rag−/− mice or in mice in which the T cells lacked IFN-γ. Furthermore, vaccination 3 months prior to the initiation of fibrosis was able to mitigate the disease. Our findings clearly demonstrate the role of T cells in regulating pulmonary fibrosis as well as suggest that vaccinia-induced immunotherapy in the lung may prove to be a novel treatment approach to this otherwise fatal disease.

Therapeutic options for systemic sclerosis related interstitial lung diseases

Interstitial lung disease (ILD) is a common manifestation of systemic sclerosis (SSc) mainly encountered in patients with diffuse disease. Unlike idiopathic interstitial pneumonias (IIP), SSc associated ILD corresponds to non-specific interstitial pneumonia (NSIP) in most cases, whereas usual interstitial pneumonia (UIP) is encountered less frequently. This explains the better prognosis of SSc associated ILD compared to IIP. However, severe restrictive lung disease represents one of the two main causes of disease-related death in SSc patients. The treatment of SSc associated ILD is not very well established. Anti-fibrosing treatments have failed to demonstrate any benefit and cyclophosphamide, which has been used in the treatment of this condition for about 15 years, has recently been evaluated in two prospective randomised studies which showed a significant but modest effect on respiratory function. Since none of the patients included in retrospective or prospective studies were selected on the basis of progression of ILD, and since only a minority of SSc patients develop severe ILD, further studies should focus on the subgroup of SSc patients with worsening ILD. A subgroup of patients with rapidly progressive ILD might benefit from pulsed intravenous cyclophosphamide combined with prednisone 15 mg daily but this remains to be confirmed.

Interstitial lung disease in systemic sclerosis

Interstitial lung disease (ILD) is a common manifestation of systemic sclerosis (SSc) and mainly encountered in patients with diffuse disease and/or anti-topoisomerase 1 antibodies. ILD develops in up to 75% of patients with SSc overall. However, SSc-ILD evolves to end-stage respiratory insufficiency in only a few patients. Initial pulmonary function tests (PFT) with measurement of carbon monoxide diffusing capacity, together with high-resolution computed tomography, allows for early diagnosis of SSc-ILD, before the occurrence of dyspnea. Unlike idiopathic ILD, SSc-ILD corresponds to non-specific interstitial pneumonia in most cases, whereas usual interstitial pneumonia is less frequently encountered. Therefore, the prognosis of SSc-ILD is better than that for idiopathic ILD. Nevertheless, ILD represents one of the two main causes of death in SSc patients. To detect SSc-ILD early, PFT must be repeated regularly, every 6 months to 1 year, depending on disease worsening. Conversely, broncho-alveolar lavage is not needed to evaluate disease activity in SSc-ILD but may be of help in diagnosing opportunistic infection. The treatment of SSc-ILD is not well established. Cyclophosphamide, which has been used for 20 years, has recently been evaluated in two prospective randomized studies that failed to demonstrate a major benefit for lung function. Open studies reported mycophenolate mofetil, azathioprine and rituximab as alternatives to cyclophosphamide. On failure of immunosuppressive agent treatment, lung transplantation can be proposed in the absence of other major organ involvement or severe gastro-esophageal reflux.

Clinical Use of Interferon-gamma

Interferon gamma (IFN-gamma), a pleotropic cytokine, has been shown to be important to the function of virtually all immune cells and both innate and adaptive immune responses. In 1986, early clinical trials of this cytokine began to evaluate its therapeutic potential. The initial studies focused on the tolerability and pharmacology of IFN-gamma and systematically determined its antitumor and anti-infection activities. In the 20-plus years since those first trials, IFN-gamma has been used in a wide variety of clinical indications, which are reviewed in this article.

Interferons and scleroderma-a new clue to understanding the pathogenesis of scleroderma?

Scleroderma or systemic sclerosis (SSc) is a complex disease characterized by vasculopathy and deregulated immune and fibroblast activation. The resulting excessive production of collagens and other extracellular matrix proteins by fibroblasts as well as the inflammatory response leads to the development of scleroderma. Recently, some emerging data have been showing a possible link between the type I and II interferons (IFNs) and SSc pathogenesis. IFNs are well-known immunomodulators and inhibitors of collagen production. However, IFN therapy also has been implicated in the development or exacerbation of several autoimmune diseases, including SSc. Some studies also showed an increase mRNA and protein levels of IFNs and several interferon stimulated genes in cells and tissues from SSc patients. In this review we discuss about a possible role for IFNs in SSc development and pathogenesis.

[Interstitial lung disease in systemic sclerosis]

INTRODUCTION

Interstitial lung diseases (ILD) in systemic sclerosis (SSc) are mainly encountered in patients with diffuse disease although they may occur less frequently in patients with limited cutaneous disease.

BACKGROUND

In SSc early detection of ILD should be achieved by high resolution computed tomography and pulmonary function tests, including measurement of DLCO. In total up to 75% of patients with SSc develop ILD but it is progressive in only a minority of patients. Unlike idiopathic ILD, SSc associated ILD corresponds to non-specific interstitial pneumonia rather than usual interstitial pneumonia in the majority of cases. This explains the better prognosis of SSc associated ILD compared with idiopathic ILD. Nevertheless ILD represents one of the two main causes of death in SSc.

VIEWPOINT

The treatment of SSc associated ILD is not well established. Anti-fibrosing treatments have failed to demonstrate benefit and cyclophosphamide, which has been used for about 15 years in the treatment of this condition, has recently been evaluated in two prospective randomised studies which showed a significant but modest effect on respiratory function.

CONCLUSION

A subgroup of patients with rapidly progressive ILD might benefit from pulsed intravenous cyclophosphamide combined with prednisone 15 mg daily, but this remains to be confirmed.

Off-label uses of biologics in dermatology: Interferon and intravenous immunoglobulin (Part 1 of 2)

The introduction of a number of biologic therapies into the market has revolutionized the practice of dermatology. These therapies include interferons, intravenous immunoglobulin, infliximab, adalimumab, etanercept, efalizumab, alefacept, and rituximab. Most dermatologists are familiar with the Food and Drug Administration-approved indications of these medications. However, numerous off-label uses have evolved. As part 1 of a 2-part series, this article will review the literature regarding the off-label uses of the interferons and intravenous immunoglobulin in dermatology.

A placebo-controlled trial of interferon gamma-1b in patients with idiopathic pulmonary fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis is a progressive, fatal disease with no known efficacious therapy.

METHODS

In a double-blind, multinational trial, we randomly assigned 330 patients with idiopathic pulmonary fibrosis that was unresponsive to corticosteroid therapy to receive subcutaneous interferon gamma-1b or placebo.

RESULTS

Over a median of 58 weeks, interferon gamma-1b therapy did not significantly affect the primary end point of progression-free survival, defined as the time to disease progression or death, and no significant treatment effect was observed on measures of lung function, gas exchange, or the quality of life. Ten percent of patients in the interferon gamma-1b group died, as compared with 17 percent of patients in the placebo group (P=0.08). Treatment with interferon gamma-1b was associated with more frequent constitutional symptoms. However, the rates of treatment adherence and premature discontinuation of treatment were similar in the two groups. More pneumonias were reported among patients in the interferon gamma-1b group, but the incidence of severe or life-threatening respiratory tract infections was similar in the two groups.

CONCLUSIONS

In a well-defined population of patients with idiopathic pulmonary fibrosis, interferon gamma-1b did not affect progression-free survival, pulmonary function, or the quality of life. Owing to the size and duration of the trial, a clinically significant survival benefit could not be ruled out.

Interferons and their application in the diseases of the lung

Interferons (IFNs) are a family of cytokine mediators that are critically involved in alerting the cellular immune system to viral infections of host cells. There are three major classes of IFNs, as follows: IFN-alpha; IFN-beta; and IFN-gamma. IFNs are being investigated and applied in various respiratory disorders, including interstitial lung diseases, lung cancer, malignant mesothelioma, malignant pleural effusions, and respiratory infections. Recent promising preliminary results concerning patients with idiopathic pulmonary fibrosis who have been treated with IFN-gamma1b should prompt the performance of further confirmatory well-designed multicenter trials. IFN-gamma is emerging as an important cytokine for use in the treatment of patients with infectious diseases, including multidrug-resistant pulmonary TB. A better understanding of IFN biology, indications, side effect profiles, and toxicity management will aid in optimizing its use in the treatment of patients. The purpose of this article is, therefore, to review the current clinical use of IFNs in the treatment of patients with respiratory diseases.

Current concepts in radiation enteritis and implications for future clinical trials

BACKGROUND

Radiation enteritis is one of the most feared complications of abdominal and pelvic radiation. Once its occurs, the process is relentless and may result in the patient's death. Available treatment is only supportive. Recent progress in molecular biology has shed some light on the pathogenesis of radiation enteritis and other diseases that are characterized by excessive fibrosis. New treatment modalities may be devised to improve the outcome of patients who are affected with this complication.

METHODS

A literature search was used to identify the common denominator between many radiation-induced fibrotic conditions and other sclerotic diseases. Factors that affect the disease process and possible therapeutic interventions were evaluated.

RESULTS

The hyperstimulation of transforming growth factor beta1 (TGF-beta1) leads to increased fibrosis and, ultimately, organ failure. Interferon gamma (IFN-gamma) inhibits the effects of TGF-beta1 in the nucleus. The fibrotic process may be reverted by IFN-gamma in various pathologic conditions.

CONCLUSIONS

Radiation enteritis and other radiation-induced, long-term complications are characterized by excessive stimulation of TGF-beta1. Preliminary studies suggest that IFN-gamma may be effective in the treatment of patients with radiation-induced cutaneous fibrosis. IFN-gamma should be considered in Phase I-II studies to assess its toxicity and efficacy in the treatment of patients with radiation enteritis.

The importance of balanced pro-inflammatory and anti-inflammatory mechanisms in diffuse lung disease

The lung responds to a variety of insults in a remarkably consistent fashion but with inconsistent outcomes that vary from complete resolution and return to normal to the destruction of normal architecture and progressive fibrosis. Increasing evidence indicates that diffuse lung disease results from an imbalance between the pro-inflammatory and anti-inflammatory mechanisms, with a persistent imbalance that favors pro-inflammatory mediators dictating the development of chronic diffuse lung disease. This review focuses on the mediators that influence this imbalance.

Potential methods to prevent interstitial fibrosis in renal disease

Almost all forms of end stage renal disease (ESRD) are characterised by progressive interstitial fibrosis and tubular atrophy. Since most forms of chronic renal failure are initiated by inflammatory processes, anti-inflammatory strategies can be successful, if initiated early, in preventing progression of the disease process. Unfortunately, in most cases the disease is only detected clinically following robust progression of interstitial fibrosis. In these patients, control of secondary risk factors, such as hypertension and hyperglycaemia, can slow the progression rate but cannot stop the process completely. Certainly, ACE inhibitors remain the mainstay of preserving renal function. However, additional therapies are needed for the effective treatment of progressive renal fibrosis. A number of compounds have shown some very potent antifibrotic properties in vitro and in vivo, and are currently undergoing further evaluation. This review discusses the most promising among them. However, few of the therapeutic agents discussed here have been tested clinically. Studies evaluating the potential of a number of these have just commenced whereas for many others clinical use is still many years away. However, some very promising reagents may enhance our clinical arsenal within a relatively short period of time.

Treating systemic sclerosis in 2001

Systemic sclerosis (SS) is characterized by sclerosis of the dermis and internal organs and by vascular abnormalities. Although the pathophysiology of the disease has been partly elucidated, the efficacy of long-term treatments remains limited, with no significant increase in survival in prospective studies. Conventional drug treatments are disappointing in clinical practice, and in a recent prospective randomized study standard-dose D-penicillamine was not more effective than mini-dose D-penicillamine. New long-term treatments are emerging for diffuse SS, including cyclophosphamide for patients with progressive interstitial lung disease or stem cell transplantation for those with early organ involvement. The most effective treatments remain symptomatic, such as angiotensin-converting enzyme inhibitors for acute renal crisis, calcium channel antagonists for Raynaud's phenomenon, and proton pump inhibitors for the complications of gastroesophageal reflux. This review article focuses on long-term treatments that are most likely to be effective and suggests symptomatic treatment strategies tailored to specific organ involvements.

Antifibrotic therapy for the treatment of pulmonary fibrosis

Fibroproliferative lung disease is prevalent and associated with high mortality. The pathogenesis of fibrotic lung disease involves inflammation, mesenchymal cell proliferation, and deposition of interstitial matrix components, such as collagen and fibronectin. Corticosteroids and other immunosuppressive medications have been routinely employed, but have demonstrated only marginal efficacy. Even though this information has been known for some time, the optimal medical regimen for treating pulmonary fibrosis remains largely undefined. This article addresses the rationale for, and efficacy of, antifibrotic regimens used to treat humans with fibrotic lung diseases.

Fibrosis of the lung and other tissues: new concepts in pathogenesis and treatment

Tissue fibrosis can lead to significant organ dysfunction and resulting patient morbidity and mortality. Unfortunately, the therapeutic repertoire is currently limited, nonspecific, and largely ineffective. While the pathogenesis is incompletely understood, evidence is accumulating that immune and cytokine mediated mechanisms are critical. In this review, data will be provided to support the role of Type 2 cytokines in the pathogenesis of fibrosis. The importance of the role of the pro-fibrogenic cytokine TGF-beta and CD40-CD40 ligand mediated fibroblast activation will also be evaluated. Finally, novel therapeutic options based on inhibiting these pathways will be described.

Interferon-gamma in 5 patients with cutaneous radiation syndrome after radiation therapy

BACKGROUND

Irradiation can cause acute inflammatory responses as well as chronic fibrotic alterations of the skin. Cutaneous radiation fibrosis evokes a complex of therapeutic problems. However, therapeutic options, apart from surgical approaches, are limited.

PATIENTS AND METHODS

Five female patients suffering from severe cutaneous fibrosis were treated with interferon-gamma on a low-dose regimen, 3 x 100 microg/week subcutaneously for 6 months, then once per week for another 6 months. In 4 patients, skin thickness was measured with high-frequency (20 MHz) ultrasound in a clinically well-defined target skin lesion. In 1 patient, nuclear magnetic resonance imaging was performed to quantify the extent of cutaneous radiation fibrosis and to monitor the therapeutic outcome.

RESULTS

All patients suffered from radiation-induced cutaneous fibrosis. Additionally, in 1 patient, a fistula, as assessed by lymph vessel scintigraphy, and in another patient a radiation ulcer was diagnosed. In all patients, reduction of radiation-induced fibrosis could be documented. Both fistula and radiation ulcer regressed completely under interferon-gamma therapy.

CONCLUSION

Low-dose interferon-gamma therapy is a new and effective treatment modality for cutaneous radiation fibrosis caused by radiation therapy. The positive impact of interferon-gamma on our patients warrants randomized double-blind trials on therapy of radiation fibrosis.

Molecular mechanisms of TGF-(beta) antagonism by interferon (gamma) and cyclosporine A in lung fibroblasts

Lung fibrosis is a fatal condition of excess extracellular matrix (ECM) deposition associated with increased transforming growth factor beta (TGF-beta) activity. Although much is known about its pathological features, our understanding of the signal transduction pathways resulting in increased ECM and collagen deposition in response to TGF-beta is still incompletely defined. We have previously reported that a JunD homodimer of the transcription factor AP-1 is specifically activated by TGF-beta in lung fibroblasts. Here we demonstrate that JunD is also specifically required for TGF-beta-induced effects. Antisense against JunD, but not c-fos or c-jun, significantly inhibited collagen deposition in response to TGF-beta in primary human lung fibroblasts. We then investigated the ability of pharmacological agents to inhibit TGF-beta-induced signaling and collagen deposition. Cs-A and IFN-gamma, but not glucocorticoids, cyclophosphamide, or azathioprine, inhibited TGF-beta-induced signaling, as assessed by luciferase reporter gene assays, and collagen deposition. TGF-beta antagonism by Cs-A was associated with direct inhibition of JunD activation, as demonstrated by electrophoretic mobility shift analyses. In contrast, the effects of IFN-gamma required signal transducer and activator of transcription (STAT)-1. We thus identify the JunD isoform of AP-1 as an essential mediator of TGF-beta-induced effects in lung fibroblasts. TGF-beta-induced signaling and collagen deposition are efficiently antagonized by Cs-A and IFN-gamma treatment, both of which exhibit distinct molecular mechanisms of action. These observations therefore offer novel targets for future therapy of fibrotic lung disease.

Effects of pentoxifylline, pentifylline and gamma-interferon on proliferation, differentiation, and matrix synthesis of human renal fibroblasts

BACKGROUND

Kidneys that progress to end-stage renal failure are almost invariably characterized by the presence of tubulointerstitial fibrosis. Therapeutic interventions to halt the progressive deterioration of renal function are still limited. Pentoxifylline, pentifylline, and gamma-interferon have shown a potential benefit in the treatment of fibrotic processes in the skin and lung. Thus, the aim of the present study was the analysis of potential anti-fibrotic effects of these substances on human kidney fibroblasts in vitro.

METHODS

Primary renal fibroblasts were established from human kidney biopsies and were studied in addition to two renal fibroblast cell lines. Cells were first growth arrested by withdrawal of fetal calf serum (FCS) and subsequently stimulated with 10% FCS in the presence of different concentrations of pentoxifylline (PTX), pentifylline (PTF), or gamma-interferon (IFN-gamma). Fibroblast proliferation was determined by bromodeoxyuridine incorporation and cell counts. Northern and western blot hybridizations for basic fibroblast growth factor (FGF)-2 and transforming growth factor (TGF)-beta1 were performed to analyse inhibitory effects. The effects of all three substances on matrix synthesis were evaluated by immunoblot analyses and ELISA for collagen type I and fibronectin after stimulation with TGF-beta1. Finally, differentiation into myofibroblasts was examined by double immunofluorescence staining for alpha-smooth-muscle actin and Hoechst dye H33258.

RESULTS

PTX and PTF resulted in a dose- and time-dependent inhibition of proliferation in all fibroblast lines (maximum 78.9+/-6.2% at 500 microg/ml PTX). Conversely, IFN-gamma had only modest effects on fibroblast proliferation, resulting in a maximum of 36.0+/-6.1% inhibition at 500 U/ml. Northern blot hybridizations determined that FGF-2 mRNA levels in fibroblasts were decreased up to 73.7 and 91.5% by PTX (1000 microg/ml) and PTF (100 microg/ml), whereas IFN-gamma led to a reduction of 46.2% at 1000 U/ml, indicating that the inhibitory effects of all three substances may be mediated through inhibition of FGF-2 synthesis. These findings were corroborated by immunoblot analyses where again PTX and PTF had the strongest inhibitory effects. No change in TGF-beta1 mRNA levels was noted. Synthesis of cellular and secreted collagen type I was robustly inhibited by PTX and PTF, whereas IFN-gamma exerted the strongest inhibitory effect on fibronectin synthesis and secretion. In addition, IFN-gamma down-regulated the expression of alpha-smooth-muscle actin up to 73.3% (at 1000 U/ml) whereas PTX and PTF resulted in a down-regulation of up to 49.7+/-1.8 and 80.0+/-4.4% (at 1000 and 100 microg/ml) respectively. PTF was in all experiments about 10 times more potent than equimolar concentrations of PTX.

CONCLUSIONS

PTX and PTF exerted robust inhibitory effects on fibroblast proliferation, extracellular matrix synthesis, and myofibroblastic differentiation. Conversely, IFN-gamma caused strong inhibition of fibronectin synthesis and alpha-smooth-muscle cell actin expression but had only weak inhibitory influences on fibroblast proliferation and collagen type I synthesis. Inhibitory effects of all three substances on proliferation may be mediated through inhibition of FGF-2 synthesis.

Transforming growth factor-beta mRNA and protein in hypertrophic scar tissues and fibroblasts: antagonism by IFN-alpha and IFN-gamma in vitro and in vivo

Hypertrophic scarring (HSc) following burn injury is a common, disfiguring, and functionally limiting form of dermal fibrosis, compromising recovery. Previously, elevated levels of transforming growth factor-beta1 (TGF-beta1), a fibrogenic cytokine, were found in wounds and serum of severely injured patients, antagonized in part by treatment with systemic interferon-alpha2b (IFN-alpha2b) both in vitro and in vivo. It is hypothesized that in wound healing after injury, platelets are an initial source of TGF-beta, but wound fibroblasts may be capable, after activation, of autoamplification of the initial response to injury by increasing TGF-beta mRNA and protein that may subsequently be responsive to IFN therapy with IFN-alpha or IFN-gamma or both. Using three pairs of site-matched HSc and normal fibroblasts from the same individuals, nonconfluent and near confluent fibroblasts were treated with TGF-beta, and cell proliferation and collagen production were assayed using cell counting and 18O2 isotopic uptake into hydroxyproline before analysis by gas chromatography-mass spectrometry (GC-MS). HSc and normal fibroblasts were assayed for the production of TGF-beta protein secretion using ELISA for TGF-beta1, TGF-beta2, and TGF-beta3 after acidification of medium samples from 96-h cultures. HSc and normal fibroblasts were treated with IFN-alpha2b or IFN-gamma or both for 96 h. Quantitative RT-PCR and Northern analysis were performed using newly synthesized internal standards for human TGF-beta1. TGF-beta stimulates both HSc and normal fibroblast proliferation. Collagen synthesis is greater in HSc than in normal fibroblasts and is maximally stimulated at 75 pM TGF-beta. TGF-beta stimulated collagen metabolism is antagonized by IFN-alpha or IFN-gamma or both in an additive fashion. HSc and normal fibroblasts not only possess the mRNA for TGF-beta1 but also secrete mature TGF-beta protein. Treatment of HSc and normal fibroblasts with IFN-alpha2b or IFN-gamma antagonizes TGF-beta protein production, and additive effects occur. RT-PCR demonstrates that after IFN treatment, downregulation of TGF-beta1 mRNA accounts in part for the reduction in protein secretion in HSc fibroblasts. Elevations of systemic TGF-beta may be due to wound fibroblasts. TGF-beta synthesis and antagonism of fibroblast TGF-beta protein secretion occurs with either IFN-alpha or IFN-gamma, in part by downregulation of TGF-beta1 mRNA levels.

Severe hepatic fibrosis in Schistosoma mansoni infection is controlled by a major locus that is closely linked to the interferon-gamma receptor gene

Lethal disease due to hepatic periportal fibrosis occurs in 2%-10% of subjects infected by Schistosoma mansoni in endemic regions such as Sudan. It is unknown why few infected individuals present with severe disease, and inherited factors may play a role in fibrosis development. Schistosoma mansoni infection levels have been shown to be controlled by a locus that maps to chromosome 5q31-q33. To investigate the genetic control of severe hepatic fibrosis (assessed by ultrasound examination) causing portal hypertension, a segregation analysis was performed in 65 Sudanese pedigrees from the same village. Results provide evidence for a codominant major gene, with.16 as the estimated allele A frequency predisposing to advanced periportal fibrosis. For AA males, AA females, and Aa males a 50% penetrance is reached after, respectively, 9, 14, and 19 years of residency in the area, whereas for other subjects the penetrance remains <.02 after 20 years of exposure. Linkage analysis performed in four candidate regions shows that this major locus maps to chromosome 6q22-q23 and that it is closely linked (multipoint LOD score 3.12) to the IFN-gammaR1 gene encoding the receptor of the strongly antifibrogenic cytokine interferon-gamma. These results show that infection levels and advanced hepatic fibrosis in human schistosomiasis are controlled by distinct loci; they suggest that polymorphisms within the IFN-gammaR1 gene could determine severe hepatic disease due to S. mansoni infection and that the IFN-gammaR1 gene is a strong candidate for the control of abnormal fibrosis observed in other diseases.

Interferon gamma in survivors of the Chernobyl power plant accident: new therapeutic option for radiation-induced fibrosis

BACKGROUND

One of the remarkable clinical consequences of the Chernobyl accident was skin involvement, leading to extensive cutaneous fibrosis. Apart from surgery, no established treatment is available.

METHODS

A group of survivors, working in or present at the accident site on April 26, 1986, and a few days thereafter, were examined, treated, and followed-up in 6-month intervals from September 1991 to November 1995. Eight individuals were identified as suffering from excessive cutaneous fibrosis. Skin thickness was measured with high-frequency (20 MHz) ultrasound in a clinically well-defined target skin lesion, in addition to histologic confirmation of radiation fibrosis. Interferon gamma was scheduled for all patients on a low-dose regimen (3 x 50 microg/week s.c.). In 2 patients, interferon was discontinued after the first injection, due to withdrawal of consent. In 6 patients, interferon was continued for 30 months, with 1 injection weekly for a further 6 months. Treatment was discontinued in November 1994. Four patients in the treated group and 1 of the 2 patients treated only once ("untreated patients") were reexamined 1 year later.

RESULTS

In all individuals treated for 36 months, a significant (p < 0.005) reduction of radiation fibrosis could be determined, in contrast to a significant (p < 0.005) increase in the 2 untreated patients. Follow-up 1 year after discontinuation of the interferon treatment demonstrated significant (p < 0.005) recurrence of fibrosis.

CONCLUSION

Low-dose interferon appears to be a safe and effective treatment of cutaneous radiation fibrosis following accidental exposure to high doses of ionizing radiation. Long-term supportive therapy may be required.

Interferon-alpha does not improve outcome at one year in patients with diffuse cutaneous scleroderma: results of a randomized, double-blind, placebo-controlled trial

OBJECTIVE

To determine whether interferon-alpha (IFNalpha) reduces the severity of skin involvement in early (<3 years) diffuse scleroderma.

METHODS

In a randomized, placebo-controlled, double-blind trial, 35 patients with early scleroderma received subcutaneous injections of either IFNalpha (13.5 x 10(6) units per week in divided doses) or indistinguishable placebo. Outcomes assessed were the modified Rodnan skin score, as determined by a single observer at baseline, 6 months, and 12 months, as well as data on renal, cardiac, and lung function. Pre- and posttreatment skin biopsy samples were analyzed and blood was obtained for assessment of procollagen peptide levels.

RESULTS

There were 11 withdrawals from the IFNalpha group and 3 from the placebo group due to either toxicity, lack of efficacy, or death. In the intent-to-treat analysis, there was a greater improvement in the skin score in the placebo group between 0 and 12 months (mean change IFNalpha -4.7 versus placebo -7.5; P = 0.36). There was also a greater deterioration in lung function in patients receiving active therapy, as assessed by either the forced vital capacity (mean change IFNalpha -8.2 versus placebo +1.3; P = 0.01) or the diffusing capacity for carbon monoxide (mean change IFNalpha -9.3 versus placebo +4.7; P = 0.002). Skin biopsy showed no significant decrease in collagen synthesis in the IFNalpha group, and no significant differences in the levels of procollagen peptides were seen between the 2 groups.

CONCLUSION

This study suggests that IFNalpha is of no value in the treatment of scleroderma, and that it may in fact be deleterious.

Interferon-gamma in the treatment of systemic sclerosis: a randomized controlled multicentre trial

We report the results of a randomized controlled multicentre study on interferon-gamma (IFN-gamma) treatment of systemic sclerosis as determined by skin sclerosis, renal and other organ involvement, global assessment, subjective symptoms and quality of life. Forty-four patients were enrolled into the trial, 27 in the treatment group and 17 in the control group. All patients presented with type I or type II scleroderma. Twenty-nine patients (64%) finished the study. The mean duration of Raynaud's phenomenon and skin sclerosis was 15.3 and 10.8 years, respectively. The skin scores tended to improve in the treatment group (P > 0.05). Mouth aperture increased significantly from 38.5 to 47.7 mm in the treatment group (P < 0.001). Subanalysis of IFN-gamma treated patients with normalized skin sclerosis scores >/=1 showed significant improvement in both skin involvement and subjective symptoms (P < 0.05). Organ involvement improved in eight of 18 treatment patients and in three of 11 control patients. It worsened in three of 18 treatment patients and in four of 11 control patients. One control patient died due to cardiorespiratory failure during the study. No deterioration of renal function occurred during IFN-gamma treatment. There was a significant improvement in quality of life parameters in the control group but not in the treatment group. Plasma levels of neopterin increased significantly during IFN-gamma treatment but not in the control group, whereas N-terminal procollagen III peptide levels did not change in either group. There was a high frequency of mild to moderate influenza-like adverse events during IFN-gamma treatment. Only four of nine drop-out patients, however, experienced symptoms most probably associated with IFN-gamma treatment. We conclude that IFN-gamma therapy has mild beneficial effects on skin sclerosis and disease-associated symptoms in type I and II scleroderma. IFN-gamma treatment was associated with acceptable tolerability and did not induce major renal dysfunction in our patients.

Low-dose methotrexate in the treatment of widespread morphea

BACKGROUND

Low-dose methotrexate (MTX) has been shown to be effective in the treatment of systemic sclerosis.

OBJECTIVE

We evaluated the effect of low-dose MTX on widespread morphea in a 24-week trial.

METHODS

Oral MTX, 15 mg/week, was administered to nine patients. Clinical records (modified skin score [MSS], durometer score, and the scores on a visual analogue scale (VAS) of feelings of tightness and itching), as well as laboratory data were examined. Serum aminoterminal propeptide of type III procollagen (PIIINP) was determined at weeks 0, 12, and 24.

RESULTS

At the end of the 24-week treatment period, significant improvement was observed in MSS (P=.01) and the VAS score for tightness (P < .01), whereas the durometer score (P=.07) and the VAS for itching (P=.07) showed a tendency toward improvement. PIIINP level did not alter. No serious adverse events were noted.

CONCLUSION

These results suggest a beneficial effect of MTX on widespread morphea. Because spontaneous improvements are not uncommon, prospective double-blind, placebo-controlled studies are necessary to determine the usefulness of MTX in this disease.

Management of collagen vascular diseases in childhood

Collagen vascular diseases seen in children include systemic, discoid and neonatal lupus, dermatomyositis, scleroderma, juvenile rheumatoid arthritis, and, in rare cases, Sjogren's syndrome. Although these diseases are uncommon in children, when seen, they are associated with significant morbidity. This review describes the clinical features of each condition and provides an overview of treatment options now available. These include numerous systemic treatments which can be used as steroid-sparing agents.

Management of systemic sclerosis: the art and science

There have been substantial strides in the therapy of systemic sclerosis (SSc) in recent years, particularly in the management of individual organ manifestations. Effective treatments are available for SSc renal crisis and many of the gastrointestinal manifestations of the disease. Raynaud's phenomenon, a nearly universal problem in SSc, also may be effectively managed. Treatment of the pulmonary complications, pulmonary hypertension and interstitial lung disease, remains difficult. Patients with early, diffuse SSc are the best candidates for experimental therapies intended to modify the overall disease process. Most disease-modifying agents have been directed at the fibrotic and inflammatory processes characteristic of SSc and have achieved little success. Future therapies may target mediators of vascular dysfunction in SSc. The success of future therapeutic trials will depend on collaborative efforts between treatment centers.

A proximal element within the human alpha 2(I) collagen (COL1A2) promoter, distinct from the tumor necrosis factor-alpha response element, mediates transcriptional repression by interferon-gamma

Previous studies have shown that interferon-gamma (IFN-gamma) inhibits type I collagen gene expression through both transcriptional and post-transcriptional mechanisms (Kahäri et al., 1990). In the present study, using transient cell transfections of human dermal fibroblast cultures with a series of 5' deletion promoter/CAT reporter gene constructs, we have identified the IFN-gamma-response element of the human alpha 2(I) collagen gene (COL1A2) promoter. Specifically, we have identified a segment of the proximal promoter region, located between nucleotides -161 and -125 relative to the transcription start site, as critical for down-regulation of COL1A2 promoter activity by IFN-gamma. This IFN-gamma response element (IgRE) is clearly distinct from the previously described tumor necrosis factor-alpha response element (TaRE) located between nucleotides -265 and -241 of the COL1A2 promoter, a difference which is likely to explain the additive inhibitory effect of these two cytokines. The inhibitory effect of IFN-gamma was dose-dependent and rapidly induced, requiring less than 5 min exposure of fibroblast cultures. Gel mobility shift assays indicated that a highly specific nuclear protein complex bound to this 37-base pair region of promoter. Competition experiments with oligonucleotides spanning discrete segments of this promoter region mapped the binding element within a distinctive pyrimidine-rich sequence. Point mutations within the latter revealed that this element plays a crucial role not only in the IFN-gamma response, but also in the basal activity of the proximal promoter. Substitution mutations within the IgRE of the -161/CAT construct attenuated the promoter response to IFN-gamma, as measured in transient cell transfections, and eliminated specific DNA/protein complex formation, as measured by gel mobility shift assay. UV-crosslinking experiments indicated that two DNA/protein complexes were formed with the IgRE, with molecular weights around 55 kDa and 30 kDa, corresponding to proteins of approximately 30 kDa and approximately 6 kDa, respectively. Our results further clarify the molecular mechanisms involved in the regulation of type I collagen gene expression by IFN-gamma.

Treatment of systemic sclerosis

Guidelines for the conduct of clinical trials in progressive systemic sclerosis have been recommended to determine drug efficacy better. To date, the results of disease-modifying drugs in scleroderma have been disappointing. The treatment of esophagitis has been revolutionized by omeprazole. Raynaud's phenomenon can be treated with calcium channel blockers and iloprost. Scleroderma renal crisis can be treated with aggressive blood pressure control using angiotensin converting enzyme inhibitors. The best treatment for rapidly progressive scleroderma lung is still unknown. Future treatments in scleroderma should be tested with the use of recommended guidelines.

Safety and efficacy of recombinant gamma interferon in the treatment of systemic sclerosis

OBJECTIVE

To evaluate the safety and efficacy of recombinant gamma interferon (rIFN gamma) in the treatment of patients with systemic sclerosis.

METHODS

Sixteen patients with systemic sclerosis were treated with r-IFN gamma, 60 micrograms m-2 (low dose, n = 10) and 150 micrograms m-2 (high dose, n = 6), three times weekly in an open phase I/II trial of eight months duration. The patients were stratified in low and high dose according to the severity and the extent of scleroderma; the two groups were comparable.

RESULTS

The treatment was well tolerated. The most common side effects, almost certainly related to r-IFN gamma, were fever, chills, dizziness, headache, and severe flu-like syndrome with decreasing intensity with the time of treatment. Severe aphthous stomatitis (n = 1), ventricular tachycardia (n = 1), severe oesophageal ulcers due to gastro-oesophageal reflux (n = 1), disease exacerbation alone with frank arthritis and slight pericardial effusion (n = 1), and inability to conform to the requirements of the study (n = 1) were the reasons for discontinuing treatment. Side effects and degree of response were evident during the first five months of treatment. A significant decrease in mean skin thickness score was observed and was higher in the high dose group. Reactive oxygen species of peripheral neutrophils and soluble interleukin-2 receptor serum concentrations were higher than those of normal individuals at study entry and decreased in parallel with clinical improvement.

CONCLUSIONS

Treatment of systemic sclerosis patients with r-IFN gamma was relatively safe and well tolerated for doses as high as 150 micrograms m-2 three times weekly. Side effects and the degree of response can be seen during the first months of therapy and can be used as predictors of ultimate toxicity or response. The drug seems to be effective in treating cutaneous scleroderma.

Effects of antirheumatic agents on cytokines

A review of the literature concerning the effects of traditional antirheumatic drugs on cytokines and the cytokine and anticytokine approaches already used in the therapy of rheumatoid arthritis (RA) is presented. Many antirheumatic drugs are capable of cytokine modulation in vitro. Corticosteroids inhibit the transcription of a broad spectrum of genes including those encoding monocyte, T cell-derived cytokines and several hemopoietic growth factors, whereas drugs such as cyclosporin A and D-penicillamine interfere with T cell activation more specifically by suppressing interleukin 2 (IL-2) production. The in vivo effects of drug therapy on cytokines in RA patients are less well established. Gold compounds reduce circulating IL-6 levels and the expression of monocyte-derived cytokines, such as IL-1, tumor necrosis factor (TNF), and IL-6, in the rheumatoid synovium. Decreases in circulating IL-6, soluble IL-2 (sIL-2R), and TNF receptors and in synovial fluid IL-1 levels have been reported with methotrexate. Reductions in circulating IL-6 and sIL-2R concentrations have also been observed with cyclosporin and corticosteroids, whereas azathioprine reduces IL-6 but not sIL-2R. Studies on sulfasalazine are conflicting and the in vivo effects of D-penicillamine and antimalarials have not been studied yet. Interferon gamma therapy is not effective in RA but may prove a useful antifibrotic for systemic sclerosis. Colony stimulating factors improve the granulocytopenia associated with Felty's syndrome or drug toxicities but can induce arthritis flares and should be reserved to treat infectious complications. Promising results are being obtained with selective antagonism of TNF and IL-1 in RA, and combinations of anticytokine strategies with traditional antirheumatic drugs have been already envisaged. These should preferably be based in a broader knowledge of the effects of antirheumatic agents on the cytokine network.

Treatment of severe localized scleroderma by plasmapheresis--report of three cases

We report three patients with severe, localized scleroderma, and with elevated titres of antinuclear antibodies, who were treated by plasmapheresis in combination with systemic steroid therapy. The therapeutic effectiveness of plasmapheresis was assessed on the basis of improvement in cutaneous and joint lesions. In all cases, significant improvement occurred after 2 months of therapy. Thus, in addition to treating systemic sclerosis, plasmapheresis can also be recommended for treatment of severe cases of localized scleroderma with elevated titres of antinuclear antibodies and antibodies to ss-DNA.

Scleroderma in children

Childhood scleroderma may present in a variety of clinical forms that differ in clinical presentation, extracutaneous features, clinical course, and outcome. All include hardening of the skin as a major feature. This article reviews these various entities, focusing on primarily the clinical features. In addition, current concepts regarding pathogenesis and treatment are discussed.

Adhesion molecules in scleroderma: collagen binding integrins

In summary, adhesion molecules are likely to play a prominent role in scleroderma pathogenesis and evolution. Endothelial adhesion molecules required for leukocyte extravasation are upregulated in affected tissue, though the mechanism is unclear. Certainly, endothelial adhesion molecule expression is seen in the context of other diseases not characterized by fibrosis. Adhesion molecules on the fibroblast, particularly those that play a role in fibroblast collagen interactions, may be very important. The ability of fibroblasts to organize collagen fibrils, and to exert forces across collagenous tissue, is likely to involve a prominent role of alpha 2 beta 1 integrin. Enhanced organization and contraction of newly formed collagen, as well as unregulated procollagen production, may be intimately linked in this disease process. At least two factors that strongly enhance fibroblast force generation could potentially influence other aspects of scleroderma. TGF beta is a potent stimulus for collagen production and has been found to be elevated in lesional scleroderma. Endothelin 1 is also a potent vasoconstrictor and is elevated in scleroderma patient serum as well [60,62-65]. Its apparent role in other fibrocontractive diseases suggests that its potential role in the pathogenesis of scleroderma deserves additional attention.

Interferon-gamma, an anti-fibrogenic cytokine which binds to heparan sulfate

Interferon-gamma is a T cell secreted cytokine. It has a great number of biological activities, among which is the down regulation of collagen molecules. IFN-gamma acts through cell surface receptors, but also binds to heparan sulfate proteoglycans. In vivo, it is postulated that the heparan sulfate/IFN-gamma interaction can modulate the activity and availability of the cytokine.

Protracted high-dose interferon gamma therapy for chronic experimental nephropathy

This study focused on the utility of interferon gamma (IFN gamma) as an anti-fibrotic drug in renal experimental fibrosis; the nephropathy was induced by two doses of Adriamycin (ADR) in 20 Sprague Dawley rats, 10 of which were randomly assigned to receive IFN gamma (45,000 UI) on alternate day for 16 weeks. At the end of the follow up, ADR rats treated with IFN gamma developed massive proteinuria, slight renal insufficiency, and presented diffuse glomerulosclerosis, tubulo interstitial infiltration and fibrosis. No difference was found in the composition of tubulo-interstitial infiltrates, mainly consisting in CD4+T lymphocytes with a minor component of CD8+T cells, in comparison with rats treated with ADR alone. These observations demonstrate the inefficacy of a protracted high-dose treatment with IFN gamma in chronic experimental nephropathy with interstitial fibrosis.

Effects of tumor necrosis factor-alpha on connective tissue metabolism in normal and scleroderma fibroblast cultures

Recent studies have demonstrated that tumor necrosis factor-alpha (TNF-alpha) selectively decreases production of collagens I and III, the major types of collagen in the dermis, and increases production of collagenase in cultured dermal fibroblasts. The effects of TNF-alpha on collagens I, III and VI, fibronectin and collagenase gene expression by fibroblasts derived from normal individuals and patients with systemic sclerosis (SSc) were studied. SSc is characterized by excessive accumulation of collagen in the skin and in certain organs. TNF-alpha inhibited collagen production and mRNA levels of collagens I and III and of fibronectin, and stimulated collagenase activity and collagenase mRNA levels in SSs fibroblasts. Levels of mRNA for alpha 1 (VI) and alpha 3 (VI) collagen and for beta-actin were unaltered in SSc fibroblasts incubated with TNF-alpha. Similar results were observed for mRNA levels in normal fibroblasts incubated with TNF-alpha. These results suggest that TNF-alpha could be expected to be beneficial in the treatment of SSc. In addition, our results indicated that collagen-VI expression is regulated independently from expression of collagens I and III, and expression of fibronectin and collagens I and III are regulated in parallel in fibroblasts treated with TNF-alpha.