安岡 秀剛

IgG4-related disease (IgG4-RD) is a recently recognized disease entity characterized by high serum IgG4 concentrations and infiltration of IgG4+ plasma cells with hyperplastic ectopic germinal centres at affected sites. Although the underlying immune mechanism of this disease remains unclear, T cells are abundantly present at affected sites and key players in IgG4-RD pathogenesis. The role of T cell subsets has been investigated thoroughly in this disease. Recent advances in this field have clarified the importance of T follicular helper cells. In this review, we describe the role of T follicular helper cells in the disease process of IgG4-RD, in particular, for IgG4 class-switching, plasmablast and plasma cell differentiation, and germinal centre formation.

Background: The potential efficacy of immunosuppressive (IS) treatment has been reported in patients with pulmonary arterial hypertension (PAH) associated with connective tissue disease (CTD), but its positioning in the treatment algorithm remains uncertain. The aim of this study was to identify predictors of favorable responses to first-line IS treatment. Methods and Results: This single-center retrospective study included 30 patients with PAH accompanied by systemic lupus erythematosus (SLE), mixed CTD (MCTD), or primary Sjögren’s syndrome (SS) who received first-line IS treatment alone or in combination with pulmonary vasodilators. When short-term treatment response was defined as an improvement in World Health Organization functional class at 3 months, 16 patients (53%) were short-term responders. Simultaneous diagnosis of PAH and CTD, and the use of immunosuppressants, especially intravenous cyclophosphamide, in addition to glucocorticoids were identified as independent predictors of a short-term response (P=0.004 and 0.0002, respectively). Cumulative rates free of PAH-related death were better in short-term responders than non-responders (P=0.04), and were best in patients with a simultaneous diagnosis of PAH and CTD who were treated initially with a combination of glucocorticoids and immunosuppressants. Conclusions: Patients with a simultaneous diagnosis of PAH and CTD, including SLE, MCTD, and primary SS, should receive intensive IS treatment regimens to achieve better short- and long-term outcomes.

IgG4-related disease (IgG4-RD) is a systemic disorder characterized by elevated serum IgG4 level, which is mediated by T follicular helper 2 (Tfh2) cell. However, the cytokines responsible for enhancing IgG4 production remain unclear in IgG4-RD. The aim of this study was to identify responsible Tfh2-related cytokines (interleukin (IL)-4 and IL-21) for enhancing IgG4 production in IgG4-RD. Peripheral blood mononuclear cells obtained from consecutive patients with active, untreated IgG4-RD and healthy controls were examined. The production of both IgG and IgG4 were significantly increased by stimulation with IL-4 alone as well as IL-21 alone compared to background stimulation with anti-CD40 antibody in IgG4-RD. On the other hand, the IgG4/IgG ratio was statistically higher by stimulation with IL-4 alone compared to the other Tfh2-related cytokines including IL-21 in IgG4-RD. IgG4 production was not increased by stimulation with IL-4 in healthy controls. These results suggest that IL-4 can contribute to the shift of balance of IgG subclasses toward IgG4 compared to the other Tfh2-related cytokines in IgG4-RD.

Objectives Differentiating IgG4-related disease (IgG4-RD) from multicentric Castleman's disease (MCD) is challenging because both diseases present high serum IgG4. The objective of this study is to clarify the differences in characteristics and identify a clinically useful approach to differentiate these two diseases. Methods Forty-five consecutive patients with untreated active IgG4-RD and 33 patients with MCD were included in this study, who visited our institution from January 2000 to August 2016. The clinical and laboratory findings for the patients of the two diseases were compared. Various combinations of the distinctive findings were evaluated to identify the most efficient differentiating features between IgG4-RD and MCD. Results The levels of serum IgG4 were not different between the two diseases. Orbits, lacrimal glands, salivary glands or pancreas were involved in 88.9% of IgG4-RD cases and only in 3.0% of MCD cases. All MCD cases involved lymph nodes. Atopic history was characteristic for IgG4-RD. The levels of C reactive protein (CRP) with a cut-off of 0.80 mg/dL and IgA with a cut-off of 330 mg/dL were the most distinctive. The combination of â € Orbits, lacrimal glands, salivary glands or pancreas involvement, atopic history, or non-involvement of lymph node' and â € CRP ≤ 0.8 mg/dL or IgA ≤ 330 mg/dL' yielded the probability of 97.8% in IgG4-RD, while that of 3.0 % in patients with MCD. Conclusions Our study revealed distinct features between IgG4-RD and MCD. Differentiating between the diseases based on those distinct features, including distribution of organ involvement, atopic history, levels of IgA and CRP, was a useful approach.

Objective To compare the efficacy and safety between tocilizumab added to methotrexate and tocilizumab switched from methotrexate in patients with active rheumatoid arthritis (RA). Methods This is a 2-year randomised, controlled study. RA patients with moderate or high disease activity despite methotrexate were randomly assigned either to tocilizumab added to methotrexate (add-on) or tocilizumab switched from methotrexate (switch). The primary endpoint was the DAS28 remission rate at week 24. Secondary objectives included other clinical efficacy indices, radiological outcomes assessed with the van der Heijde-modified total Sharp scoring system (mTSS), and safety. Results Of 223 randomised patients, 83% completed 52 weeks. DAS28 remission rates at week 24 were 70% for add-on and 55% for switch (p=0.02), but they became comparable at week 52 (72% vs 70%, p=0.86). Structural remission rates (mTSS=0.5) at week 52 were not different (66% vs 64%, p=0.92). However, clinically relevant radiographic progression rates (CRRP; mTSS=3) tended to be higher with the switch than with the add-on (15% vs 7%, p=0.07). Radiographic progression in the CRRP patients was larger with the switch than with the add-on (9.0/year vs 5.0/year, p=0.04). The difference in the mean C-reactive protein of the CRRP patients was significant for the first 24 weeks (1.56 vs 0.49, p=0.001) but not for the following 28 weeks (0.10 vs 0.04, p=0.1). Overall safety was preferable in the switch group. Conclusions In RA patients with inadequate response to methotrexate, tocilizumab added to methotrexate more rapidly suppressed inflammation than tocilizumab switched from methotrexate, leading to superior clinical efficacy and prevention of joint destruction.

Systemic sclerosis (SSc) is a disorder characterized by immune dysfunction, microvascular injury, and fibrosis. Organ involvement in patients with SSc is variable however, pulmonary involvement occurs in up to 90% of patients with SSc. Interstitial lung disease (ILD) is a major cause of mortality and, thus, a major determinant in the prognosis of patients with SSc. This review summarizes current findings about the characteristics of ILD in patients with SSc, selection of patients with SSc-ILD who are candidates for the treatment, and current treatment options.

Objective. To elucidate the pathologic role of follicular helper T (Tfh) cells and their subsets in active, untreated IgG4-related disease. Methods. Fifteen patients with active, untreated, biopsy-proven IgG4-related disease, 24 patients with primary Sjogren's syndrome (SS), 12 patients with allergic rhinitis, and 23 healthy controls were evaluated. Tfh cells were defined as CD3+CD4+CXCR5+CD45RA- cells. Circulating Tfh cell subsets among CXCR5+CD45RA-CD4+ T cells were defined as Tfh17 cells (CXCR3-CCR6+), Tfh1 cells (CXCR3+CCR6-), or Tfh2 cells (CXCR3-CCR6-). CD19+CD20-CD27+CD38+ cells were defined as plasmablasts. Serum cytokine levels (interleukin-4 [IL-4], IL-10, IL-21, and IL-33) were measured by cytometric bead array or enzyme-linked immunosorbent assay. Results. Patients with IgG4-related disease had significantly increased levels of Tfh2 cells compared to healthy controls or patients with primary SS or allergic rhinitis. Increased Tfh2 levels were strongly associated with increased serum IgG4 levels and the IgG4:IgG ratio in IgG4-related disease. A positive correlation was observed between Tfh2 counts, plasmablast counts, and serum IL-4 levels. Interestingly, levels of plasmablasts and serum IL-4 and IgG4 decreased after treatment with glucocorticoids, whereas no obvious change was observed in Tfh2 cell counts. Conclusion. The Tfh2 cell count was specifically increased in IgG4-related disease and was correlated with elevated serum levels of IgG4 and IL-4 and plasmablast counts. Tfh2 cells were the only component that was not affected by glucocorticoid treatment, suggesting that Tfh2 cells are the cell type implicated in IgG4-related disease.

Objectives. To explore the effectiveness and safety of tocilizumab (TCZ) with or without methotrexate (MTX) in active rheumatoid arthritis (RA) patients showing inadequate responses to DMARDs and/or TNF inhibitors in clinical practice.Methods. We observed consecutive 115 RA patients initiating TCZ treatment in Keio University Hospital, dividing them into two groups with (TCZ + MTX group) or without MTX (TCZ group), and evaluated clinical, functional and structural outcomes besides safety at week 52.Results. Overall mean age, RA duration, and DAS28-ESR were 55.4, 8.4 years, and 5.0, respectively. Proportions of the prior use of TNF inhibitors and concomitant MTX were 45.5% and 57.4%, respectively. Mean dose of concomitant MTX was 8.4 mg/week. Baseline characteristics were comparable between the groups. TCZ improved disease activity measured by DAS28-ESR to 2.1 at week 52 overall, without significant difference between the groups. Clinical (DAS28-ESR < 2.6), functional (HAQ-DI <= 0.5), and structural (Delta TSS <= 0.5) remission rates in the TCZ group and the TCZ + MTX group were 79.1%/63.8% (P = 0.10), 62.8%/54.4% (P = 0.40), and 70.0%/53.8% (P = 0.61), respectively. Retention rates were 81.0% in the TCZ + MTX group and 88.5% in the TCZ group (P = 0.47). The rate of serious adverse events was comparable between the groups.Conclusions. TCZ was clinically, functionally, and radiographically effective and safe either with or without low-dose MTX.

Systemic sclerosis (SSc) is characterized by excessive fibrosis of the skin and internal organs due to fibroblast proliferation and excessive production of extracellular matrix (ECM). We have shown that insulin-like growth factor binding protein (IGFBP)-5 plays an important role in the development of fibrosis in vitro, ex vivo, and in vivo. We identified a membrane-associated adaptor protein, downstream of tyrosine kinase/docking protein (DOK)5, as an IGFBP-5-regulated target gene using gene expression profiling of primary fibroblasts expressing IGFBP-5. DOK5 is a tyrosine kinase substrate associated with intracellular signaling. Our objective was to determine the role of DOK5 in the pathogenesis of SSc and specifically in IGFBP-5-induced fibrosis. DOK5 mRNA and protein levels were increased in vitro by endogenous and exogenous IGFBP-5 in primary human fibroblasts. DOK5 upregulation required activation of the mitogen-activated protein kinase (MAPK) signaling cascade. Further, IGFBP-5 triggered nuclear translocation of DOK5. DOK5 protein levels were also increased in vivo in mouse skin and lung by IGFBP-5. To determine the effect of DOK5 on fibrosis, DOK5 was expressed ex vivo in human skin in organ culture. Expression of DOK5 in human skin resulted in a significant increase in dermal thickness. Lastly, levels of DOK5 were compared in primary fibroblasts and lung tissues of patients with SSc and healthy donors. Both DOK5 mRNA and protein levels were significantly increased in fibroblasts and skin tissues of patients with SSc compared with those of healthy controls, as well as in lung tissues of SSc patients. Our findings suggest that IGFBP-5 induces its pro-fibrotic effects, at least in part, via DOK5. Furthermore, IGFBP-5 and DOK5 are both increased in SSc fibroblasts and tissues and may thus be acting in concert to promote fibrosis.

Objective: To assess the efficacy of epoprostenol treatment in Japanese patients with pulmonary arterial hypertension (PAH) associated with connective tissue disease (CTD). Methods: Sixteen patients with PAH-CTD treated with continuous intravenous epoprostenol at a single center between 2000 and 2009 were enrolled. Baseline characteristics, short-term and long-term outcomes, predictors of mortality, and safety profiles were evaluated. For survival analysis, 16 controls were selected who matched the underlying CTD, World Health Organization functional class, and use of PAH drugs, except for epoprostenol. Results: Six patients had systemic lupus erythematosus, five had mixed CTD, four had systemic sclerosis, and one had primary Sjögren's syndrome. The mean pulmonary arterial pressure (mPAP), cardiac index (CI), pulmonary vascular resistance, and functional class were significantly improved during the first 6 months of epoprostenol treatment. Cumulative survival rates at 1, 2, and 3 years in epoprostenol-treated patients were 69, 69, and 55 %, respectively, and were significantly better than those of the controls. Functional class, CI at baseline, and reduction of mPAP at 6 months were identified as predictors of survival. Adverse events, including flushing and catheterrelated infection, were frequent, but all patients tolerated the treatment. Conclusion: Based on the improvements in both shortterm and long-term outcomes among our patient cohort, epoprostenol is an effective treatment for CTD patients with advanced PAH. © Japan College of Rheumatology 2013.

Introduction: Systemic sclerosis (SSc) is more prevalent in women. Our goal is to determine the effects of 17 beta-estradiol (E2) on the development of fibrosis and to compare circulating levels of estrogens in SSc patients and healthy controls. Methods: Using primary human dermal fibroblasts, we evaluated the effect of E2 on fibronectin (FN) expression with and without the estrogen receptor (ER) antagonist ICI 182,780, inhibitors of signaling, propyl-pyrazole-triol, an ER alpha specific ligand, and genistein, an ER beta selective ligand, to identify the signaling pathways mediating E2's effect. We confirmed the fibrotic effect of E2 in human skin using an ex vivo organ culture model. Lastly, we measured levels of E2 and estrone in serum samples from SSc patients with diffuse cutaneous involvement and healthy controls using mass spectrometry. Results: E2 increased expression of FN in dermal fibroblasts. ICI 182,780, inositol-1,4,5-triphosphate inhibitor, and p38 mitogen-activated protein kinase inhibitor blocked the effects of E2 on FN. Propyl-pyrazole-triol, but not genistein, significantly increased FN expression. Ex vivo, E2 induced fibrosis of human skin. The effects of E2 were abrogated by ICI 182,780. Circulating levels of E2 and estrone were significantly increased in sera of patients with diffuse cutaneous SSc. Conclusion: Our findings implicate estrogens in the fibrotic process and may explain the preponderance of SSc in women. ICI 182,780 or other ER signaling antagonists may be effective agents for the treatment of fibrosis.

Introduction: Altered phenotypes of circulating monocytes of patients with systemic sclerosis (SSc) have been reported, but the role of these alterations in the pathogenesis of SSc remains unclear. This study was undertaken to identify molecules that are preferentially expressed by SSc monocytes, and to investigate the roles of these molecules in the pathogenic process of SSc. Methods: We analyzed circulating CD14(+) monocytes isolated from 36 patients with SSc and 32 healthy control subjects. The monocytes' gene expression profiles were assessed by Oligo GEArray (R) (SABiosciences, Frederic, MA, USA) and semiquantitative or quantitative PCR; their protein expression was evaluated in culture supernatants of unstimulated monocytes by immunoblotting or ELISA, and by immunocytostaining. Monocyte chemoattractant activity of CCL2 was assessed in a TransWell (R) system (Corning Incorporated, Corning, NY, USA) in the presence or absence of chondroitin sulfate (CS). Results: A step-wise approach to profiling gene expression identified that versican and CCL2 were upregulated in SSc monocytes. Subsequent analysis of proteins expressed in monocyte culture supernatants confirmed enhanced production of versican and CCL2 in SSc monocytes compared with control monocytes. CCL2 bound to CS chains of versican and colocalized with versican in the monocytes' Golgi apparatus. Finally, CCL2 had a greater ability to mediate monocyte migration when bound to CS chains, because this binding provided efficient formation of CCL2 gradients and protection from protease attack. Conclusion: Circulating monocytes with elevated versican and CCL2 levels may contribute to the fibrotic process in a subset of SSc patients by amplifying a positive feedback loop consisting of versican, CCL2, and the influx of monocytes.

Objective. To clarify the characteristics, survival and predictors of mortality in Japanese patients with pulmonary arterial hypertension (PAH) associated with CTD. Methods. This single-centre cohort study enrolled 70 consecutive patients with PAH-CTD who visited a tertiary referral centre in Japan between 1970 and 1990 (n = 30, historical group) and between 2000 and 2009 (n = 40, recent group). Baseline clinical features, haemodynamic parameters and ANA profiles were recorded. The Cox proportional hazards regression model was used to determine independent factors associated with an increased risk of mortality. Results. MCTD and SLE were the major underlying CTDs, comprising 43% and 29% of PAH patients respectively, whereas SSc was less common (19%). Anti-U1RNP antibody was the most prevalent ANA (61%). The cumulative survival rate was significantly better in the recent group in comparison with the historical group (76% vs 26% at 3 years; P &lt; 0.001). When both groups were combined, World Health Organization functional class III or IV at diagnosis was identified as an independent predictor of mortality, whereas modern PAH drug use was associated with a favourable outcome. Conclusion. The major PAH-CTD population in Japan suffers from MCTD or SLE with anti-U1RNP antibody, in contrast to PAH-CTD patients in the USA and Europe. Modern PAH treatment has improved survival rates, but long-term outcomes are still unsatisfactory. Independent predictors of mortality indicate that early diagnosis and the prompt use of PAH drugs should improve survival.

Our previous studies have demonstrated increased expression of insulin-like growth factor binding protein-5 (IGFBP-5) in fibrotic tissues and IGFBP-5 induction of extracellular matrix (ECM) components. The mechanism resulting in increased IGFBP-5 in the extracellular milieu of fibrotic fibroblasts is unknown. Since Caveolin-1 (Cav-1) has been implicated to play a role in membrane trafficking and signal transduction in tissue fibrosis, we examined the effect of Cav-1 on IGFBP-5 internalization, trafficking and secretion. We demonstrated that IGFBP-5 localized to lipid rafts in human lung fibroblasts and bound Cav-1. Cav-1 was detected in the nucleus in IGFBP-5-expressing fibroblasts, within aggregates enriched with IGFBP-5, suggesting a coordinate trafficking of IGFBP-5 and Cav-1 from the plasma membrane to the nucleus. This trafficking was dependent on Cav-1 as fibroblasts from Cav-1 null mice had increased extracellular IGFBP-5, and as fibroblasts in which Cav-1 was silenced or lipid raft structure was disrupted through cholesterol depletion also had defective IGFBP-5 internalization. Restoration of Cav-1 function through administration of Cav-1 scaffolding peptide dramatically increased IGFBP-5 uptake. Finally, we demonstrated that IGFBP-5 in the ECM protects fibronectin from proteolytic degradation. Taken together, our findings identify a novel role for Cav-1 in the internalization and nuclear trafficking of IGFBP-5. Decreased Cav-1 expression in fibrotic diseases likely leads to increased deposition of IGFBP-5 in the ECM with subsequent reduction in ECM degradation, thus identifying a mechanism by which reduced Cav-1 and increased IGFBP-5 concomitantly contribute to the perpetuation of fibrosis.

Rationale. The hallmarks of allergic asthma are airway inflammation, obstruction, and remodeling. Airway remodeling may lead to irreversible airflow obstruction with increased morbidity and mortality. Despite advances in the treatment of asthma, the mechanisms underlying airway remodeling are still poorly understood. We reported that insulin-like growth factor (IGF) binding proteins (IGFBPs) contribute to extracellular matrix deposition in idiopathic pulmonary fibrosis; however, their contribution to airway remodeling in asthma has not been established. Objectives: We hypothesized that IGFBP-3 is overexpressed in asthma and contributes to airway remodeling. Methods: We evaluated levels of IGFBP-3 in tissues and bronchoalveolar lavage fluid from patients with asthma at baseline and 48 hours after allergen challenge, in reparative epithelium in an in vitro wounding assay, and in conditioned media from cytokine- and growth factor-stimulated primary epithelial cells. Measurements and Main Results: IGFBP-3 levels and distribution were evaluated by Western blot, ELISA, and immunofluorescence. IGFBP-3 is increased in vivo in the airway epithelium of patients with asthma compared with normal control subjects. The concentration of IGFBP-3 is increased in the bronchoalveolar lavage fluid of patients with asthma after allergen challenge, its levels are increased in reparative epithelium in an in vitro wounding assay and in the conditioned medium of primary airway epithelial cell cultures stimulated with IGF-I. Conclusions: Our results suggest that one mechanism of allergic airway remodeling is through the secretion of the profibrotic IGFBP-3 from IGF-I-stimulated airway epithelial cells during allergic inflammation.

We have previously shown that insulin-like growth factor-binding protein-5 (IGFBP-5) is overexpressed in fibrotic lung tissues and that it induces production of extracellular matrix components such as Collagen and fibronectin both in vitro and in vivo. We recently observed mononuclear cell infiltration in lung tissues of mice expressing IGFBP-5. We therefore examined the role of IGFBP-5 on the migration of immune cells. Migration assays demonstrated that IGFBP-5 induced migration of peripheral blood mononuclear cells (PBMCs) in a dose-dependent manner. Preferential migration of monocytes/macrophages, natural killer cells, and T cells was observed. Moreover, the CD4/CD8 ratio of migrating cells was significantly higher in vitro and in vivo in response to IGFBP-5. IGFBP-5 resulted in preferential migration of activated CD4(+) T cells and monocytes. Interestingly, IGFBP-5 also induced migration of primary human lung fibroblasts. Exogenous administration of IGFBP-5 induced activation of mitogen-activated protein kinase (MAPK) signaling cascade but not PI3K in PBMCs. IGFBP-5-induced migration was blocked by the MEK1/2 inhibitor U0126, suggesting that IGFBP-5-induced migration occurs via MAPK activation. Furthermore, monocytes treated with recombinant IGFBP-5 expressed the mesenchymal markers a-smooth muscle actin and fibronectin in vitro and in vivo, suggesting that IGFBP-5 can induce the transformation of monocytes into mesenchymal cells. Collectively, our results suggest that IGFBP-5 induces cell migration via MAPK-dependent and IGF-I-independent mechanisms.

We have previously shown that insulin-like growth factor (IGF) binding protein-5 (IGFBP-5) is overexpressed in lung fibrosis and induces the production of extracellular matrix components, such as collagen and fibronectin, both in vitro and in vivo. The exact mechanism by which IGFBP-5 exerts these novel fibrotic effects is unknown. We thus examined the signaling cascades that mediate IGFBP-5-induced fibrosis. We demonstrate for the first time that IGFBP-5 induction of extracellular matrix occurs independently of IGF-1, and results from IGFBP-5 activation of MAPK signaling, which facilitates the translocation of IGFBP-5 to the nucleus. We examined the effects of IGFBP-5 on early growth response (Egr)-1, a transcription factor that is central to growth factor-mediated fibrosis. Egr-1 was up-regulated by IGFBP-5 in a MAPK-dependent manner and bound to nuclear IGFBP-5. in fibroblasts from Egr-1 knockout mice, induction of fibronectin by IGFBP-5 was abolished. Expression of Egr-1 in these cells rescued the extracellular matrix-promoting effects of IGFBP-5. Moreover, IGFBP-5 induced cell migration in an Egr-1-dependent manner. Notably, Egr-1 levels, similar to IGFBP-5, were increased in vivo in lung tissues and in vitro in primary fibroblasts of patients with pulmonary idiopathic fibrosis. Taken together, our findings suggest that IGFBP-5 induces a fibrotic phenotype via the activation of MAPK signaling and the induction of nuclear Egr-1 that interacts with IGFBP-5 and promotes fibrotic gene transcription. (Am J Pathol 2009, 175:605-615; DOI: 10.2353/ajpath.2009.080991)

Pulmonary fibrosis is a phenotype that results from a variety of conditions and is associated with significant morbidity and mortality. Ongoing research in the field is driven by the need for effective treatments for pulmonary fibrosis. In this review, we highlight mechanisms that regulate gene expression in pulmonary fibrosis at multiple levels. Potential pathogenic mechanisms involve genetic background and transcriptional, posttranscriptional, translational, posttranslational, and epigenetic mechanisms. Pulmonary fibrosis results from abnormal gene expression and regulation that arise from a combination of inherited/acquired genetic alterations and environmental triggers. Collectively, these alterations result in increased expression of extracellular matrix components such as collagen and fibronectin and in the observed fibrosis. Insights gained from mechanisms identified to induce and/or perpetuate fibrosis in the lung will yield new targets for the development of more effective therapies.

Systemic sclerosis (SSc) is a connective tissue disease of unknown etiology. A hallmark of SSc is fibrosis of the skin and internal organs. We recently demonstrated increased expression of IGFBP-3 and IGFBP-5 in primary cultures of fibroblasts from the skin of patients with SSc. In vitro, IGFBP-3 and IGFBP-5 induced a fibrotic phenotype and IGFBP-5 triggered dermal fibrosis in mice. To assess the ability of IGFBPs to trigger fibrosis, we used an ex vivo human skin organ culture model. Our findings demonstrate that IGFBP-3 and IGFBP-5, but not IGFBP-4, increase dermal and collagen bundle thickness in human skin explants, resulting in substantial dermal fibrosis and thickening. These fibrotic effects were sustained for at least two weeks. Our findings demonstrate that human skin ex vivo is an appropriate model to assess the effects of fibrosis-inducing factors such as IGFBPs, and for evaluating the efficacy of inhibitors/therapies to halt the progression of fibrosis and potentially reverse it.

Systemic sclerosis (SSc) is characterized by excessive fibrosis and autoantibody production. However, the pathogenesis of SSc is still under investigation. We have demonstrated that a novel testicular antigen, protein highly expressed in testis (PHET), is overexpressed in SSc dermal fibroblasts and targeted by autoantibodies. PHET was identified by screening of HepG2 cDNA library using an SSc serum and was found to belong to UniGene cluster of sperm associated antigen 9 (SPAG9) from its nucleotide sequence. PHET mRNA expression was examined by RT-PCR using mRNA panels of human tissues, and PHET mRNA was highly expressed only in testis in normal tissues. Anti-PHET antibodies were detected in 8.4% of sera of SSc patients by immunoblotting, and associated with diffuse scleroderma and lung involvement. Expression of PHET mRNA and protein was increased in cultured SSc dermal fibroblasts compared with control fibroblasts. These results suggest that ectopic expression of PHET in dermal fibroblasts induces autoantibody production against PHET in patients with SSc. (c) 2006 Elsevier B.V. All rights reserved.

We have recently shown that insulin-like growth factor-binding protein (IGFBP)-5 is overexpressed in idiopathic pulmonary fibrosis lung tissues and increases collagen and fibronectin deposition. Here, we further examined the effect of IGFBP-5 in vivo by intratracheal administration of replication-deficient adenovirus expressing human IGFBP-5 (Ad5), IGFBP-3 (Ad3), or no cDNA (cAd) to wild-type mice. Increased cellular infiltration and extracellular matrix deposition were observed in mice after Ad5 administration compared with Ad3 and cAd. Mononuclear cell infiltration consisted predominantly of T lymphocytes at day 8. By day 14, the number of infiltrating T cells decreased, whereas that of B cells and monocytes/macrophages increased. IGFBP-5 also induced migration of peripheral blood mononuclear cells in vitro, suggesting that in vivo mononuclear cell infiltration may be the direct result of IGFBP-5 expression. a-Smooth muscle actin and Mucin-1 co-localized in cells of mice treated with Ad5, suggesting that IGFBP-5 induced epithelial-mesenchymal transition. in addition, exogenous IGFBP-5 induced a-smooth muscle actin expression in primary fibroblasts and epithelial-mesenchymal transition of pulmonary epithelial cells in vitro. In conclusion, our results suggest that overexpression of IGFBP-5 in mouse lung results in fibroblast activation, increased extracellular matrix deposition, and myofibroblastic changes. Thus, the IGFBP-5-induced fibrotic phenotype in vivo may represent a novel model to better understand the pathogenesis of fibrosis.

Objective. To determine the role of insulin-like growth factor binding protein 5 (IGFBP-5) in the development of skin fibrosis in vivo, by examining the effect of overexpression of IGFBP-5 in mouse skin. Methods. Wild-type C57BL/6J mice were injected subcutaneously with replication-deficient serotype 5 adenovirus expressing human IGFBP-3 (Ad3), IGFBP-5 (AM), or no complementary DNA (cAd). Mice were killed 3, 8, or 22 days postinjection. The dermal thickness and dermal collagen bundle thickness in skin sections were measured. The deposition of collagen in the extracellular matrix (ECM) was quantified using the Sircol assay. Expression of proliferating cell nuclear antigen (PCNA) and fibronectin, as determined by immunohistochemical analysis, was used to evaluate fibroblast activation, and vimentin and a-smooth muscle actin (alpha-SMA) were used to evaluate the fibroblast phenotype. Results. Adenovirally expressed IGFBP was detected in. dermal fibroblasts, endothelial cells, epithelial cells, and muscle bundles in Ad3- and Ad5-injected mice. Increased collagen deposition, denser dermal connective tissue, and increased collagen bundle thickness were observed in IGFBP-5-overexpressing mice. Dermal thickness and collagen bundle thickness were significantly increased in Ad5-injected mice compared with cAd- and Ad3-injected mice. Treatment with Ad5 resulted in a dose-dependent increase in dermal and collagen bundle thickness. Increased deposition of collagen and fibronectin, increased numbers of PCNA-positive fibroblasts, as well as increased numbers of vimentin- and alpha-SMA-double-positive fibroblasts were detected in the dermis of IGFBP-5-overexpressing mouse skin. Conclusion. IGFBP-5 is a key mediator of fibrosis. IGFBP-5 mediates its profibrotic effects through fibroblast activation, increased ECM deposition, and myoribroblastic transformation of dermal fibroblasts. Overexpression of IGFBP-5 provides a novel model for studying the pathogenesis of skin fibrosis in systemic sclerosis.

Objective. To evaluate whether atorvastatin can increase bone marrow-derived circulating endothelial precursors (CEPs) and improve the vascular symptoms in patients with systemic sclerosis (SSc; scleroderma). Methods. The study was designed as an open-label, prospective study involving 14 patients with SSc who received 10 mg/day of atorvastatin for 12 weeks and were followed up for the subsequent 4 weeks. CEPs were quantified at weeks 0 (pretreatment), 4, 8, 12 (during treatment), and 16 (posttreatment) by cell sorting followed by 3-color flow cytometry. Raynaud's phenomenon variables, global measures, and psychological scales as well as circulating angiogenic factors and endothelial activation/injury markers were serially assessed. The potential of CEPs to differentiate into mature endothelial cells was examined in cultures with angiogenic stimuli. Results. None of the patients experienced an adverse event, but 1 dropped out because of an excessive decrease in serum total cholesterol. Atorvastatin treatment resulted in a 1.7- to 8.0-fold increase in CEPs from baseline levels (P &lt; 0.0001), but the numbers returned to within baseline levels at posttreatment. However, 8 patients (62%) experienced a gradual decrease in the number of CEPs, even while taking atorvastatin. Variables indicating the extent of Raynaud's phenomenon improved significantly, and up-regulated levels of angiogenic factors and vascular endothelial activation/injury markers decreased significantly during atorvastatin treatment. These variables returned to within baseline levels after discontinuation of the drug. In contrast, atorvastatin failed to improve the in vitro maturation potential of CEPs. Conclusion. The results of this pilot study suggest that atorvastatin treatment can increase CEPs and may be effective in improving Raynaud's phenomenon, even in SSc patients who have CEP dysfunction intrinsically.

Sera from patients with myasthenia gravis (MG) were screened for autoantibodies to skeletal muscle-specific antigens by immunoprecipitation assay, using rhabdomyosarcoma and leukemia cell lines. Eleven of 61 MG sera immunoprecipitated a rhabdomyosarcoma-specific 70-kDa protein, which was identified as the voltage-gated K+ channel 1.4 (Kv1.4). This antibody specificity was not detected in 30 patients with polymyositis/dermatomyositis, 9 with thymoma alone, or 30 healthy controls. Clinical features associated with anti-K(v)1.4 antibody included bulbar involvement, myasthenic crisis, thymoma, myocarditis, and QT prolongation on electrocardiogram. These findings suggest that anti-K(v)1.4 antibody is a novel autoantibody associated with a severe MG subset and thymoma. (C) 2005 Elsevier B.V. All rights reserved.

PURPOSE. Tissue atrophy and excessive fibrosis are prominent histologic features of chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation, but the underlying mechanism remains unknown. The current study was undertaken to investigate whether the increase in fibroblasts at the site of pathogenic fibrosis originated from transplanted donor cells in patients with chronic GVHD. METHODS. Lacrimal gland biopsy specimens were obtained from nine patients with chronic GVHD. The male-specific sequences detected by fluorescein in situ hybridization (FISH) and in situ hybridization (ISH) were used as markers for the donor cells in seven female patients who had received a transplant from male donors. Primary fibroblast cultures were generated from lacrimal gland biopsy specimens and examined for mismatched genetic markers between recipients and donors. RESULTS. In lacrimal gland specimens obtained from seven female patients who received a sex-mismatched transplant, 13.4% to 26.7% of CD34(+) fibroblasts that accumulated in the fibrotic lesion were donor derived, as determined by FISH for the Y-chromosome. The male-specific mRNA was also detected in the lacrimal gland fibroblasts by ISH. Primary lacrimal gland fibroblast cultures were generated from four patients with chronic GVHD and further examined for mismatched genetic markers between recipients and donors. As a result, the presence of donor origin of the fibroblasts was demonstrated by detecting the Y-chromosome sequence and donor-specific microsatellite genetic markers. CONCLUSIONS. These findings together indicate the chimeric status of accumulated CD34(+) fibroblasts in the lacrimal gland of patients with chronic GVHD. Fibroblasts originating from circulating donor-derived precursors may participate in the excessive fibrosis in these patients.

Previously, we reported a unique CD14(+)CD45(+)CD34(+) type I collagen(+) cell fraction derived from human circulating CD14(+) monocytes, named monocyte-derived mesenchymal progenitors (MOMPs). These primitive cells differentiate along mesenchymal lineages, including bone, cartilage, fat, and skeletal muscle. Here, we demonstrate that CD14(+) monocytes generate MOMPs that differentiate into cardiomyocytes. MOMPs labeled with a fluorescent marker and co-cultivated with rat cardiomyocytes for 4 weeks expressed the cardiomyocyte-specific transcription factors Nkx2.5, GATA-4, eHAND, and MEF2 and the hematopoietic/monocytic markers CD45 and CD14 within 10 days and retained their proliferative capacity for up to 16 days. A subpopulation of MOMPs subsequently expressed the cardiomyocyte-specific markers alpha-sarcomeric actinin, troponin I, and atrial natriuretic peptide on day 21. Furthermore, fluorescence-labeled, spontaneously beating cells that formed gap junctions with adjacent rat cardiomyocytes appeared in these cultures and these cells exhibited electrophysiological properties typical of ventricular myocytes. The co-cultivation of human MOMPs with rat GFP-tagged cardiomyocytes resulted in the generation of human cardiomyocytes lacking green fluorescent protein (GFP) staining, suggesting that our observations could not solely be explained by cell fusion. Our results demonstrate for the first time that human circulating CD14(+) monocytes include progenitors capable of proliferating and differentiating along the cardiomyogenic lineage via their differentiation into MOMPs.

Purpose: Studies on mortality associated with systemic sclerosis have been limited by small sample sizes. We aimed to obtain large-scale evidence on survival outcomes and predictors for this disease. Methods: We performed a meta-analysis of individual patient data from cohorts recruited from seven medical centers in the United States, Europe, and Japan, using standardized definitions for disease subtype and organ system involvement. ne primary outcome was all- cause mortality. Standardized mortality ratios and predictors of mortality were estimated. The main analysis was based only on patients enrolled at each center within 6 months of diagnosis (incident cases). Results: Among 1645 incident cases, 578 deaths occurred over 11,521 person-years of follow-up. mortality ratios varied by cohort.(1.5 to 7.2). In multivariate analyses that adjusted for age and Standardized m sex, renal (hazard ratio [HR] = 1.9; 95% confidence interval [CI]: 1.4 to 2.5), cardiac (HR = 2.8; 95% CI: 2.1 to 3.8), and pulmonary (HR = 1.6; 95% CI: 1.3 to 2.2) involvement, and anti-topoisomerase I antibodies (HR = 1.3; 95% CI: 1.0 to 1.6), increased mortality risk. Renal, cardiac, and pulmonary involvement tended to occur together (P &lt; 0.001). For patients without adverse predictors for 3 years after enrollment, the subsequent risk of death was not significantly different from that for the general population in three cohorts, but was significantly increased in three cohorts that comprised mostly referred patients. Analysis that included all cases in each center (n = 3311; total follow-up: 19,990 person-years) yielded larsel similar results. Conclusion: Systemic sclerosis confers a high mortality risk. but there is considerable heterogeneity across settings. Internal organ involvement and anti-topoisomerase I antibodies are important determinants of mortality. 0 2005 Elsevier Inc. All rights reserved.

Objective. A 3 year prospective randomized study was conducted to clarify the efficacy of intermittent cyclical etidronate therapy on corticosteroid induced osteoporosis. Methods. A group of 102 Japanese patients were enrolled, each taking &gt; 7.5 mg of prednisolone daily for at least 90 days. Patients were randomly divided into 2 treatment groups: Group E (etidronate) took 200 mg etidronate disodium per day for 2 weeks with 3.0 g calcium lactate and 0.75 mug alphacalcidol daily; Group C (control) took 3.0 g calcium lactate and 0.75 mug alphacalcidol daily. Outcome measurements included changes from baseline in bone mineral density (BMD) of the lumbar spine and the rate of new vertebral fractures at 48 and 144 weeks. Results. The mean (+/-SD) lumbar spine BMD increased 3.7+/-5.6% (p&lt;0.01) and 1.5+/-4.1% (NS) from baseline at 48 weeks and 4.8+/-6.9% (p&lt;0.005) and 0.4+/-5.0% (NS) from baseline at 144 weeks in Group E and Group C, respectively. The improvement of BMD in Group E was significantly greater than in Group C at 144 weeks (p&lt;0.01). In 3 subgroups, men and premenopausal and postmenopausal women, the postmenopausal women showed the greatest improvement. Mean percentage change in this subgroup was 10.1+/-8.0% and 1.35+/-6.4% in Group E and Group C, respectively. We noted that 2 patients in Group C had new vertebral fractures, whereas no fractures were observed in Group E. Conclusion. These results indicate that intermittent cyclical etidronate therapy is effective for the prevention and treatment of corticosteroid induced osteoporosis in patients with connective tissue diseases.