Transethnic meta-analysis identifies GSDMA and PRDM1 as susceptibility genes to systemic sclerosis.

OBJECTIVES: Systemic sclerosis (SSc) is an autoimmune disease characterised by skin and systemic fibrosis culminating in organ damage. Previous genetic studies including genome-wide association studies (GWAS) have identified 12 susceptibility loci satisfying genome-wide significance. Transethnic meta-analyses have successfully expanded the list of susceptibility genes and deepened biological insights for other autoimmune diseases. METHODS: We performed transethnic meta-analysis of GWAS in the Japanese and European populations, followed by a two-staged replication study comprising a total of 4436 cases and 14 751 controls. Associations between significant single nuclear polymorphisms (SNPs) and neighbouring genes were evaluated. Enrichment analysis of H3K4Me3, a representative histone mark for active promoter was conducted with an expanded list of SSc susceptibility genes. RESULTS: We identified two significant SNP in two loci, GSDMA and PRDM1, both of which are related to immune functions and associated with other autoimmune diseases (p=1.4×10-10 and 6.6×10-10, respectively). GSDMA also showed a significant association with limited cutaneous SSc. We also replicated the associations of previously reported loci including a non-GWAS locus, TNFAIP3. PRDM1 encodes BLIMP1, a transcription factor regulating T-cell proliferation and plasma cell differentiation. The top SNP in GSDMA was a missense variant and correlated with gene expression of neighbouring genes, and this could explain the association in this locus. We found different human leukocyte antigen (HLA) association patterns between the two populations. Enrichment analysis suggested the importance of CD4-naïve primary T cell. CONCLUSIONS: GSDMA and PRDM1 are associated with SSc. These findings provide enhanced insight into the genetic and biological basis of SSc.

Postoperative complications in patients with rheumatoid arthritis using a biological agent - A systematic review and meta-analysis.

OBJECTIVES: To evaluate, through a systematic review of the literature, the association between the use of biological disease-modifying antirheumatic drugs (bDMARDs) and surgical site infection (SSI) or wound healing delay after orthopedic surgery in patients with rheumatoid arthritis (RA). METHODS: A systematic review of articles indexed in the Cochrane Library, PubMed, and Web of Science from 1992 to 2012 was performed. The search aimed to identify studies describing SSI or wound healing delay in patients with RA treated with or without bDMARDs. Articles fulfilling the predefined inclusion criteria were reviewed systematically and their quality was appraised. RESULTS: There was no Cochrane review on this subject. We found 75 articles through specific searches of PubMed and Web of Science, and hand searching. After inclusion and exclusion by full-text review, 10 articles were found for SSI, and 5 articles for delayed wound healing. The use of bDMARDs appeared to increase the rate of SSI slightly, especially in large joint-replacement surgery. Delayed wound healing was not increased by the use of bDMARDs. However, the definitions of SSI and delayed wound healing varied between the reviewed articles. Most of the articles focused on tumor necrosis factor-α inhibitors. CONCLUSION: bDMARDs slightly increase the relative risk of SSI but not that of delayed wound healing after orthopedic surgery and should be used with appropriate caution.

Incidence and the risk factor of malignancy in Japanese patients with systemic sclerosis.

OBJECTIVE: To evaluate the incidence and risk factors for malignancy in Japanese patients with systemic sclerosis (SSc). METHODS: A cohort of 405 Japanese patients with SSc who visited Kitasato University hospital between 1973 and 2008 was analyzed retrospectively until the end of 2009. The incidence of malignancy was compared with that of the general population, with calculation of the standardized incidence ratio (SIR) and 95% confidence interval (CI). RESULTS: The cohort represented 4,787 person-years of total disease duration after the diagnosis of SSc. Of 27 malignancies clinically found, lung cancer (n=10, 37%), especially adenocarcinoma, was the most frequent, followed by breast (n=4, 15%) or gastric (n=3, 11%) cancer. SSc patients with overlapping CTD tended to have less malignancy. Multivariable analysis revealed heart involvement of SSc as a significant risk factor for breast cancer (RR 8.2, 95% CI 1.2-72.8). Other than gastric cancer, the calculated SIRs of malignancies in SSc patients were above 1 (SIR of overall malignancy 1.24, 95% CI 0.77-1.71), even though only lung cancer had a significantly elevated incidence (SIR 5.73, 95% CI 2.18-9.29). Every patient with lung cancer had interstitial lung disease (ILD) and every autopsy performed on patients with lung cancer found a primary lesion of lung cancer in their ILD lesion (n=4). CONCLUSION: Lung cancer was significantly frequent in SSc patients, which could develop on the basis of complicated ILD.

Predictors of survival and causes of death in Japanese patients with systemic sclerosis.

OBJECTIVE: To clarify the mortality rates, causes of death, and contributing clinical factors in Japanese patients with systemic sclerosis (SSc). METHODS: A cohort of 405 patients with SSc, who attended our institution during the period 1973 to 2008, was retrospectively analyzed until the end of 2009. Clinical data were obtained from medical records or autopsy reports. RESULTS: The 405 patients with SSc consisted of 310 (76.5%) survivors, 86 (21.2%) who died, and 9 who were lost to followup. Diffuse cutaneous SSc and involvement of organs other than the gastrointestinal tract were more frequent in patients who died, and were associated with a worse prognosis according to Kaplan-Meier analysis. Female sex, limited cutaneous SSc, anticentromere antibody (ACA), and overlap with Sjögren's syndrome (SS) were factors favoring a better prognosis, while overlap with myositis contributed to a poor prognosis. The overall 10-year survival rate was 88%. The patients with SSc had a significantly higher mortality than the general population (standardized mortality ratio 2.76), but the patients with ACA or overlapping SS did not. The most common causes of death were unknown ones including sudden death, followed by malignancy and infection. In patients with pulmonary arterial hypertension, sudden death was the most common cause of mortality. CONCLUSION: The overall mortality rate of patients with SSc was higher than that of the general population, probably because of poor prognostic factors including organ involvement. These factors should be carefully monitored during followup.

Elevated serum levels of resistin, leptin, and adiponectin are associated with C-reactive protein and also other clinical conditions in rheumatoid arthritis.

OBJECTIVE: Body fat is an important source of hormones and cytokines (adipokines) that not only regulate the energy balance, but also regulate the inflammatory and immune responses. This study investigated the association of clinical conditions with serum levels of adipokines in patients with rheumatoid arthritis. METHODS: Serum levels of resistin, leptin, and adiponectin were measured by enzyme-linked immunosorbent assay in 141 patients (110 women) who fulfilled the 1987 revised criteria of the American Rheumatism Association for the diagnosis of rheumatoid arthritis and in 146 normal controls (124 women). Then the correlations between adipokine levels and clinical parameters were evaluated. RESULTS: The serum resistin level did not differ between the patients and controls. However, serum leptin levels were significantly higher in male and female rheumatoid arthritis patients than in the corresponding controls, while the serum adiponectin level was significantly higher in female patients than in female controls. Multivariate analysis revealed that predictors of an elevated resistin level were female sex and C-reactive protein (CRP), while the leptin level was related to the body mass index and CRP. Predictors of an elevated adiponectin level were the use of prednisolone and CRP, however, CRP was negatively associated with adiponectin in patients with rheumatoid arthritis. CONCLUSION: The serum levels of resistin and leptin were positively associated with CRP level in patients with rheumatoid arthritis, suggesting that these adipokines may act as pro-inflammatory cytokines in this disease. The serum adiponectin level was elevated in the patients, however, it was negatively associated with CRP level. In addition, the serum levels of resistin, leptin, and adiponectin were also associated with female sex, BMI and the use of prednisolone, respectively.

Adiponectin stimulates prostaglandin E(2) production in rheumatoid arthritis synovial fibroblasts.

OBJECTIVE: Adipokines may influence inflammatory and/or immune responses. This study was undertaken to examine whether adiponectin affects the production of prostaglandin E(2) (PGE(2)) by rheumatoid arthritis synovial fibroblasts (RASFs). METHODS: Synovial tissue was obtained from patients with RA who were undergoing joint replacement surgery. Fibroblast-like cells from the third or fourth passage were used as RASFs. Expression of adiponectin receptor messenger RNA (mRNA) and protein was detected. PGE(2) (converted from arachidonic acid) was measured by enzyme-linked immunosorbent assay (ELISA). Expression of mRNA and protein for cyclooxygenase 2 (COX-2) and membrane-associated PGE synthase 1 (mPGES-1), key enzymes involved in PGE(2) synthesis, was detected in RASFs. The effects of RNA interference (RNAi) targeting the adiponectin receptor genes and the receptor signal inhibitors were examined. The influence of adiponectin on NF-kappaB activation in RASFs was measured with an ELISA kit. RESULTS: Adiponectin receptors were detected in RASFs. Adiponectin increased both COX-2 and mPGES-1 mRNA and protein expression by RASFs in a time- and concentration-dependent manner. PGE(2) production by RASFs was also increased by the addition of adiponectin, and this increase was inhibited by RNAi for the adiponectin receptor gene, or coincubation with the receptor signal inhibitors. Enhancement of NF-kappaB activation by adiponectin as well as by interleukin-1beta was observed in RASFs. CONCLUSION: Our findings indicate that adiponectin induces COX-2 and mPGES-1 expression, resulting in the enhancement of PGE(2) production by RASFs. Thus, adiponectin may play a role in the pathogenesis of synovitis in RA patients.

Exacerbation of adult-onset Still's disease, possibly related to elevation of serum tumor necrosis factor-alpha after etanercept administration.

Adult-onset Still's disease (AOSD) is a systemic inflammatory disease of unknown etiology. A 44-year-old male patient presented with AOSD complicated by macrophage activation syndrome after etanercept therapy. His serum tumor necrosis factor-α (TNF-α) level was increased dramatically after etanercept therapy. The clinical course of this case suggests that the increased TNF-α level by etanercept administration might cause macrophage activation syndrome in this case.

[A case of Münchausen syndrome with recurrent bacteremia and PR3-ANCA positivity].

A 29-year-old woman chiropractor with repeated episodes of bacteremia and positive for cytoplasmic antineutrophil cytoplasmic antibody (c-ANCA) and antiproteinase-3 (PR3) antibody had an 11-year history of asthma and repeated hospitalization. While hospitalized she developed a spiking nocturnal fever with chills and erythema of the lower leg. Her fever resolved spontaneously, but corticosteroid therapy and antibiotics did not effectively reduce her symptoms. Plain X-ray film and CT showed pulmonary changes, and lung biopsy granulomas without vasculitis. Immunological studies showed a positive PR3-ANCA (c-ANCA) test, and skin biopsy of the crural erythema showed foreign body granuloma. Multiple blood cultures were positive for several strains of bacteria, including Fusobacterium necrophurum, Mycobacterium fortuitum, and Clostridium species. When placed in a single room and monitored, she did not develop new fever or erythema. Because self-injury was assumed, she was diagnosed as having Münchausen syndrome. This is, to our knowledge, the first report of Münchausen syndrome with PR3-ANCA positivity. In patients with repeated infections, the possibility of self-injury, the development of PR3-ANCA positivity, and pulmonary granuloma with a disease profile similar to vasculitis syndrome should be considered in the definitive diagnosis.

Recurrent paralytic ileus associated with strongyloidiasis in a patient with systemic lupus erythematosus.

We present an interesting case of recurrent paralytic ileus due to strongyloidiasis in a woman who was being treated with corticosteroids and immunosuppressants for systemic lupus erythematosus (SLE). She was also a carrier of human T-cell leukemia virus type I. She had a history of strongyloidiasis 8 years earlier. Recurrent episodes of paralytic ileus due to strongyloidiasis occurred during treatment of her SLE with corticosteroids. Ivermectin was given and improved the symptoms. This case shows that symptomatic strongyloidiasis can be induced in immunocompromised hosts by immunosuppressive therapy. It is important to rule out strongyloidiasis prior to starting immunosuppressive therapy in patients from endemic areas.

[Combined effect of micafangin and itraconazole on severe aspergillosis of the bilateral pleural cavities in a patient with Wegener's granulomatosis].

Visceral fungal infections are difficult to manage in patients with collagen diseases and immunocompromised hosts. In particular aspergillosis can be a life-threatening complication in these patients. Here we report that combined use of two antifungal agents (micafangin and itraconazole) was effective against severe aspergillosis of the bilateral pleural cavities in a 48-year old male patient diagnosed with Wegener's granulomatosis. Immunosuppressive therapy with corticosteroids and cyclophosphamides improved his nasal and pulmonary symptoms, but inflammation of the bilateral pleural cavities caused bronchial fistulas. Aspergillus fumigatus then infected the bilateral pulmonary cavities through these fistulas. This patient was treated with combined therapy of ITCZ and MCFG was given to this patient because of the risk of renal dysfunction associated with AMPH-B. After 5 weeks of treatment his clinical findings had improved and the fungus was suppressed.

Inhibition of skin sclerosis by 15deoxy delta12,14-prostaglandin J2 and retrovirally transfected prostaglandin D synthase in a mouse model of bleomycin-induced scleroderma.

Hematopoietic prostaglandin D synthase (PGDS) is a key enzyme involved in production of the PGD and J series, which have various role in inflammation and immunity. We evaluated the effect of treatment with 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) or the injection of prostaglandin D(2) synthase (PGDS) cDNA expressing-retrovirally transfected fibroblasts on bleomycin (BLM)-induced scleroderma-like skin sclerosis. Daily injection of BLM (30 microg) for 4 weeks induced histological evidence of dermal sclerosis in C3H mice. We examined the effect of injection of 15d-PGJ(2) (30 ng twice a day) or PGDS expressing-retrovirally transfected fibroblast on BLM-induced dermal sclerosis. Administration of 15d-PGJ(2) (a nonenzymatic metabolite of PGD(2)) injection of PGDS cDNA-expressing fibroblasts significantly reduced dermal sclerosis, the hydroxyproline content, and dermal thickness. Moreover, 15-d PGJ2 down-regulation of the expression of transforming growth factor beta(1) and connective tissue growth factor which had been induced by BLM. Mast cells were also increased in the skin by BLM injection and there was prominent degranulation of these mast cells along with elevated plasma histamine levels. 15-d PGJ(2) and PGDS-expressing cells also suppressed degranulation of cultured mast cells and histamine release by these cells. These results show that 15-d PGJ(2) and PGDS-expressing cells can prevent experimental skin sclerosis induced by BLM and raise the possibility of therapeutic approaches targeting of PPARgamma for the skin lesion of scleroderma.

Host stromal bradykinin B2 receptor signaling facilitates tumor-associated angiogenesis and tumor growth.

We evaluated the significance of the host kallikrein-kinin system in tumor angiogenesis and tumor growth using two rodent models genetically deficient in a kallikrein-kinin system. Inoculation of Walker 256 carcinoma cells into the s.c. tissues of the back of normal Brown Norway Kitasato rats (BN-Ki rats) resulted in the rapid development of solid tumors with marked angiogenesis. By contrast, in kininogen-deficient Brown Norway Katholiek rats (BN-Ka rats), which cannot generate intrinsic bradykinin (BK), the weights of the tumors and the extent of angiogenesis were significantly less than those in BN-Ki rats. Daily administration of B(2) receptor antagonists significantly reduced angiogenesis and tumor weights in BN-Ki rats to levels similar to those in BN-Ka rats but did not do so in BN-Ka rats. Angiogenesis and tumor growth were significantly suppressed in B(2) receptor knockout mice bearing sarcoma 180 compared with their wild-type counterparts. Immunoreactive vascular endothelial growth factor (VEGF) was localized in Walker tumor stroma more extensively in BN-Ki rats than in BN-Ka rats, although immunoreactive B(2) receptor also was detected in the stroma to the same extent in both types of rats. Cultured stromal fibroblasts isolated from BN-Ki rats and BN-Ka rats produced VEGF in response to BK (10(-8)-10(-6) m), and this stimulatory effect of BK was abolished with a B(2) receptor antagonist, Hoe140 (10(-5) m). These results suggest that BK generated from kininogens supplied from the host may facilitate tumor-associated angiogenesis and tumor growth by stimulating stromal B(2) signaling to up-regulate VEGF production mainly in fibroblasts.

Inhibition of monosodium urate monohydrate crystal-induced acute inflammation by retrovirally transfected prostaglandin D synthase.

OBJECTIVE: Hematopoietic prostaglandin D synthase (H-PGDS) is a key enzyme in the production of prostaglandin D and its J series metabolites. We evaluated the antiinflammatory effect of retrovirally transfected H-PGDS in order to investigate the role of H-PGDS in monosodium urate monohydrate (MSU) crystal-induced acute inflammation. METHODS: Expression of endogenous PGDS in a murine air-pouch model of MSU crystal-induced acute inflammation was determined by real-time polymerase chain reaction. H-PGDS complementary DNA (cDNA) was retrovirally transfected into C57BL/6J fibroblasts, and the cells were designated as C57-PGDS cells. Production of prostaglandins by C57-PGDS cells was measured by enzyme immunoassay. The effect of C57-PGDS cells on crystal-induced inflammation was investigated. RESULTS: Injection of the crystals caused a rapid decrease in H-PGDS expression by infiltrating cells and by the soft tissues around the air pouches. In contrast, expression of interleukin-1beta (IL-1beta) and macrophage inflammatory protein 2 (MIP-2) as well as cellular infiltration were significantly increased during the early stage of inflammation. C57-PGDS cells, but not control cells, produced an increased amount of PGD(2) in vitro, but suppressed production of PGE(2). Injection of C57-PGDS cells into air pouches inhibited cellular infiltration and MIP-2 and IL-1beta expression. CONCLUSION: In this murine air-pouch model of MSU crystal-induced inflammation, retrovirally transfected H-PGDS cDNA could reduce cellular infiltration, at least partly by inhibiting MIP-2 and IL-1beta. These findings suggest that gene therapy with H-PGDS may be useful for treating inflammatory diseases.

Retrovirally introduced prostaglandin D2 synthase suppresses lung injury induced by bleomycin.

Hematopoietic prostaglandin D synthase (PGDS) is a key enzyme to produce prostaglandin (PG) D and J series. These PGs are involved in inflammation and immune system. The PGDS complementary DNA (cDNA)-expressing retrovirally transfected fibroblasts were introduced in vivo, and effect of the expression on lung injury induced by bleomycin was investigated in mice. Intravenous injection of PGDS cDNA-expressing fibroblasts significantly reduced lung edema, leukocyte infiltration in bronchoalveolar lavage (BAL) fluid, and pulmonary collagen content at 4 wk after instillation of bleomycin. Survival rate in mice instilled with the PGDS-expressing fibroblasts was higher than that in mice that received the mock transfection. Administration of 15-deoxy-Delta 12,14-PGJ2, which is a nonenzymatic metabolite of PGD2, also attenuated the lung injury, suggesting mediation of PGs produced by PGDS for the attenuation. Introduction of PGDS cDNA-expressing fibroblasts suppressed expression of basic fibroblast growth factor, connective tissue growth factor, and collagen messenger RNAs in the lungs, as well as the levels of total proteins and hemoglobin in BAL fluid. These data suggest that the suppressive effect of PGDS on the lung injury could be partly mediated by edema formation and inhibition of genes involved in the fibrotic change.

Host prostaglandin E(2)-EP3 signaling regulates tumor-associated angiogenesis and tumor growth.

Nonsteroidal antiinflammatories are known to suppress incidence and progression of malignancies including colorectal cancers. However, the precise mechanism of this action remains unknown. Using prostaglandin (PG) receptor knockout mice, we have evaluated a role of PGs in tumor-associated angiogenesis and tumor growth, and identified PG receptors involved. Sarcoma-180 cells implanted in wild-type (WT) mice formed a tumor with extensive angiogenesis, which was greatly suppressed by specific inhibitors for cyclooxygenase (COX)-2 but not for COX-1. Angiogenesis in sponge implantation model, which can mimic tumor-stromal angiogenesis, was markedly suppressed in mice lacking EP3 (EP3(-/-)) with reduced expression of vascular endothelial growth factor (VEGF) around the sponge implants. Further, implanted tumor growth (sarcoma-180, Lewis lung carcinoma) was markedly suppressed in EP3(-/-), in which tumor-associated angiogenesis was also reduced. Immunohistochemical analysis revealed that major VEGF-expressing cells in the stroma were CD3/Mac-1 double-negative fibroblasts, and that VEGF-expression in the stroma was markedly reduced in EP3(-/-), compared with WT. Application of an EP3 receptor antagonist inhibited tumor growth and angiogenesis in WT, but not in EP3(-/-). These results demonstrate significance of host stromal PGE(2)-EP3 receptor signaling in tumor development and angiogenesis. An EP3 receptor antagonist may be a candidate of chemopreventive agents effective for malignant tumors.

Binary regulation of interleukin (IL)-6 production by EP1 and EP2/EP4 subtypes of PGE2 receptors in IL-1beta-stimulated human gingival fibroblasts.

Prostaglandin E2 (PGE2) exerts its biological actions via EP receptors, which are divided into four subtypes of EP1, EP2, EP3 and EP4. In the present study, we investigated whether PGE2 regulated interleukin (IL)-6 production in human gingival fibroblasts (HGF) stimulated with IL-1beta and if so, which subtype(s) of PGE2 receptors were involved. Indomethacin, a cyclooxygenase inhibitor, significantly enhanced IL-1beta-induced IL-6 production by HGF, although it completely inhibited IL-1beta-induced PGE2 production. Exogenous PGE2 suppressed the IL-1beta-induced IL-6 production. Reverse transcription-polymerase chain reaction analysis demonstrated that mRNA of EP1, EP2 and EP4, but not EP3 mRNA, was expressed in unstimulated and IL-1beta-stimulated HGF. 11-deoxy-PGE1, a selective EP2/EP3/EP4 agonist, and butaprost, a selective EP2 agonist, inhibited IL-1beta-induced IL-6 production, although butaprost was less potent than 11-deoxy-PGE1. 17-phenyl-omega-trinor PGE2, an EP1 agonist, enhanced IL-1beta-induced IL-6 production. Based on these data, we suggest that PGE2 can up- or downregulate IL-1beta-induced IL-6 production via EP1 receptors or via EP2/EP4 receptors in HGF, respectively. Expression and function of EP1, EP2 and EP4 receptors in HGF may play critical roles in controlling inflammatory periodontal conditions.