Long-term changes in nail fold capillary abnormalities and serum fibroblast growth factor 23 levels in dermatomyositis patients with anti-melanoma differentiating antigen 5 antibody.

Nail fold videocapillaroscopy (NVC) abnormalities are a characteristic finding of microangiopathy in dermatomyositis (DM). The aim of the present study was to examine long-term changes in NVC abnormalities and serum fibroblast growth factor 23 (FGF23) and vascular endothelial growth factor (VEGF) levels in DM patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody (Ab). Serum levels of FGF23 and VEGF were measured by enzyme-linked immunosorbent assay. NVC abnormalities were evaluated by capillaroscopy in 11 DM patients with anti-MDA5 Ab at baseline and after treatment. NVC abnormalities included irregularly enlarged capillaries, reduced capillaries, hemorrhages, capillary ramifications, disorganization of the vascular array, loss of capillaries and giant capillaries. Serum FGF23 levels were significantly decreased in patients with anti-MDA5 Ab (0.3 ± 0.3 pmol/L) compared with healthy controls (1.0 ± 0.6 pmol/L, P < 0.01). Serum FGF23 levels significantly increased after treatment (0.3 ± 0.3 vs 1.0 ± 0.7 pmol/L, P < 0.005), but serum VEGF levels were comparable between at baseline and after treatment. At baseline, irregularly enlarged capillaries were observed in 10 of 11 patients, but after treatment, they were significantly reduced in only two (91% vs 18%, P < 0.001). Hemorrhages were observed in all 11 patients at baseline, but disappeared in all after treatment (100% vs 0%, P < 0.001). These results suggest that NVC abnormalities are reversible by treatment and that serum FGF23 levels reflect the degree of microvascular damage in DM patients with anti-MDA5 Ab.

A case of anti-BP230 antibody-positive bullous pemphigoid receiving DPP-4 inhibitor.

Bullous pemphigoid (BP) is a cutaneous autoimmune blistering disorder. Recently, it has been reported that dipeptidyl peptidase-4 inhibitors (DPP4i) is associated with the development of BP (DPP4i-BP). Patients with DPP4i-BP have autoantibodies (autoAbs) preferentially targeting full-length BP180, but not the BP180NC16a domain. In this report, we described a case of anti-BP230 antibody (Ab)-positive BP receiving DPP4i. A 78-year-old male with a medical history of type 2 diabetes receiving vildagliptin at 100 mg daily for 38 months was referred to our hospital with itching blisters on his body and extremities. Skin biopsy showed subepidermal bulla with eosinophil infiltration. Direct immunofluorescence staining revealed a linear staining pattern with complement C3 and IgG at the subepidermal basement membrane zone. By laboratory testing, autoAbs against BP180NC16a and full-length BP180 were negative by enzyme-linked immunosorbent assay (ELISA); however, anti-BP230 Abs were positive by ELISA (index: 123.91). His HLA genotype was DQB1*04:01 and 05:01. Based on these results, we diagnosed the patient with anti-BP230 Abs-positive BP associated with DPP4i. To the best of our knowledge, this is the first case of DPP4i-BP with only anti-BP230 Abs. Further accumulation of DPP4i-BP cases is needed to clarify the relationship between overall features of DPP4i-BP and anti-BP230 Abs.

Characteristics of Japanese patients with eosinophilic fasciitis: A brief multicenter study.

Eosinophilic fasciitis is a relatively rare cutaneous fibrotic condition affecting the deep fascia of the extremities, with or without peripheral blood eosinophilia. To examine the characteristics of Japanese patients with eosinophilic fasciitis, we conducted a brief, multicenter, retrospective survey at seven university hospitals. In total, 31 patients were identified as having eosinophilic fasciitis, among whom 30 patients fulfilled the Japanese diagnostic criteria. The male : female ratio was 2.3:1, and the mean age was 47.7 years. Three of the patients were under 20 years old. The possible triggering factors included muscle training, sports, walking or sitting for a long time, physical work, insect bite and drug. Co-occurrence of morphea was observed in nine cases (29%), and malignancies were associated in three (two hematological malignancies and one internal malignancy). Immunological abnormalities in the serum showed positive antinuclear antibody, positive rheumatoid factor, increased aldolase levels and increased immunoglobulin G levels. The patients were treated with either monotherapy or combination therapy by oral prednisolone (20-80 mg/day), methotrexate (6-10 mg/week), cyclosporin (100-150 mg/day), mizoribine, infliximab and phototherapy. Methylprednisolone pulse therapy was performed in six cases. By contrast, spontaneous improvement due to resting only was observed in two cases, and skin hardening was improved by withdrawal of the anticancer drug in one case. This study suggests several characteristics of Japanese patients with eosinophilic fasciitis, namely male predominance, rare pediatric occurrence, immunological abnormalities and coexistence with morphea. Systemic prednisolone is the first-line therapy, but pulse therapy is occasionally required for severe cases. The triggering events of physical stress are not so frequent as have previously been reported, and various factors or even unknown factors may be associated with the induction of eosinophilic fasciitis.

Association of functional (GA)n microsatellite polymorphism in the FLI1 gene with susceptibility to human systemic sclerosis.

OBJECTIVE: Susceptibility genes that can account for characteristic features of SSc such as fibrosis, vasculopathy and autoimmunity remain to be determined. In mice, deficiency of Friend leukaemia integration 1 transcription factor (Fli1) causes SSc-like disease with these features. The human FLI1 gene contains (GA)n microsatellite, which has been shown to be associated with expression level. Because microsatellite polymorphisms are difficult to capture by genome-wide association studies, we directly genotyped FLI1 (GA)n microsatellite and examined its association with SSc. METHODS: Genomic DNA from 639 Japanese SSc patients and 851 healthy controls was genotyped for (GA)n microsatellite using the fragment assay. The cut-off repeat number for susceptibility to SSc was determined by receiver operating characteristics (ROC) analysis. Association with susceptibility and clinical characteristics was examined using logistic regression analysis. FLI1 mRNA levels were determined using quantitative RT-PCR. RESULTS: Based on the ROC analysis, (GA)n alleles with ≥22 repeats were collectively defined as L alleles and alleles with ≤21 repeats as S alleles. (GA)n L alleles were significantly associated with susceptibility to SSc (P = 5.0e-04, odds ratio 1.34, additive model). Significant association was observed both in diffuse cutaneous and limited cutaneous SSc. Among the SSc, (GA)n L alleles were significantly enriched in the patients with a modified Rodnan total skin thickness score ≥10 compared with those with a score <10. FLI1 mRNA levels were significantly decreased in healthy controls carrying (GA)n L alleles as compared with non-carriers. CONCLUSION: Extended repeat alleles of FLI1 (GA)n microsatellite may be associated with lower FLI1 mRNA levels and susceptibility to human SSc.

Adipose-derived stromal/stem cells successfully attenuate the fibrosis of scleroderma mouse models.

AIM: Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and lung fibrosis. Although SSc has a high mortality risk, an effective treatment for the disease has not been established yet. Mesenchymal stromal/stem cells (MSCs) are multipotential nonhematopoietic progenitor cells that have the ability to regulate immune responses. Adipose-derived stromal/stem cells (ASCs), one of the types of MSCs, have the advantage of accessibility and potent immunomodulatory effects when compared with other MSCs, such as bone marrow-derived MSCs. This study aimed to investigate the antifibrotic effect of ASCs in scleroderma mouse models, including bleomycin-induced scleroderma and sclerodermatous chronic graft-versus-host disease (Scl-cGVHD) models. METHOD: ASCs were intravenously administered to a bleomycin-induced scleroderma or Scl-cGVHD model on day 0. We compared the skin and lung fibrosis of scleroderma model mice between the ASC-treated group and control group. RESULTS: Administration of ASCs attenuated the skin and lung fibrosis of bleomycin-induced scleroderma and Scl-cGVHD model mice compared to that in the control mice. Immunohistochemical staining showed that ASCs suppressed the infiltration of CD4+ , CD8+ T cells and macrophages into the dermis of bleomycin model mice compared to that in control mice. In addition, ASCs attenuated the messenger RNA expression of collagen and fibrogenic cytokines, such as interleukin (IL)-6 and IL-13, in the skin of bleomycin model mice. ASCs also reduced the frequency of fibrogenic cytokine-producing CD4+ T cells and effector B cells in the spleen of bleomycin model mice. CONCLUSION: ASCs could prove to be a potential therapeutic agent for use in patients with SSc.

Anti-transcriptional intermediary factor 1-γ antibody as a biomarker in patients with dermatomyositis.

The presence of anti-transcriptional intermediary factor (TIF)1-γ antibody (Ab) is associated with cancer in adult patients with clinically amyopathic dermatomyositis (CADM) or dermatomyositis (DM). In this study, we examined whether anti-TIF1-γ Ab levels are associated with disease activity in patients with CADM/DM. Anti-TIF1-γ Ab levels were examined in 23 patients with CADM or DM (CADM, n = 6; DM, n = 17). Baseline characteristics and outcomes were recorded, and serial measurements of anti-TIF1-γ Ab levels were obtained. Of the 23 patients with detectable anti-TIF1-γ Ab, 16 (70%) had an internal malignancy, while two (9%) had interstitial lung disease. Mean initial anti-TIF1-γ Ab levels (134 ± 47 index) were significantly decreased after 24 months (54 ± 45 index, P < 0.0001) and remained decreased thereafter. Anti-TIF1-γ Ab became negative (index value, <32) in 10 patients (43%) and remained positive (index value, ≥32) in 13 patients (57%) during the clinical course. The frequency of remission in the anti-TIF1-γ Ab-negative conversion group (100%) was significantly higher than in the sustained positive group (0%, P < 0.0001). Furthermore, mortality in the anti-TIF1-γ Ab-negative conversion group (0%) was significantly lower than that in sustained positive group (69%, P < 0.001). This study indicates that anti-TIF1-γ Ab levels are a useful and relevant surrogate marker of disease activity during follow-up monitoring.

Elevated serum B-cell activating factor levels in patients with dermatomyositis: Association with interstitial lung disease.

Patients with dermatomyositis (DM) frequently have myositis-specific autoantibodies (MSA), which are closely associated with different clinical features. Patients with anti-aminoacyl-tRNA synthetase antibody (ARS-Ab) and anti-melanoma differentiation-associated gene 5 (MDA5)-Ab often have interstitial lung disease (ILD). Recently, anti-MDA5-Ab levels have been shown to correlate with disease activity in DM patients. Thus, B cells that are stimulated by excess B-cell activating factor (BAFF) play an important role in the pathogenesis of DM through auto-Ab production. In this study, we investigated the role of BAFF in DM patients. We measured the serum BAFF levels in 56 adult DM patients (14 with anti-ARS-Ab, 18 with anti-MDA5-Ab, seven with anti-Mi-2-Ab and 17 with anti-transcriptional intermediary factor-1γ-Ab) . For a longitudinal study, 130 serum specimens from 10 DM patients with anti-MDA5-Ab were analyzed. Serum BAFF levels were significantly higher in DM patients than in healthy controls. DM patients with elevated serum BAFF levels more frequently had ILD. In subgroup analysis, DM patients with anti-ARS-Ab and DM patients with anti-MDA5-Ab exhibited increased BAFF levels compared with controls, while DM patients with other MSA showed BAFF levels comparable with controls. In the longitudinal study, serum BAFF levels in DM patients with anti-MDA5-Ab were decreased after immunosuppressive therapy along with serum levels of anti-MDA5-Ab and ferritin, which are biomarkers of disease activity. These results suggest that BAFF plays an important role in the pathogenesis of ILD in DM patients with anti-ARS and anti-MDA5-Ab. Furthermore, serum BAFF level is associated with disease activity in DM patients with anti-MDA5-Ab.

Human case of subcutaneous nodule because of a novel genetic variation of Dirofilaria sp.

A 75-year-old man presented with a 1-cm large elastic soft subcutaneous nodule on the left side of the umbilicus, which when excised showed presence of a helminthic form within the granulomatous lesions. Morphologically, the helminth was considered to be of the genus Dirofilaria, and the patient showed increased serum antibody titer against canine filaria. The partial DNA sequence of the mitochondrial 12S rRNA gene locus of this clinical isolate showed the highest nucleotide identity (89.6%) with Dirofilaria repens; however, the phylogenetic analysis addressed the haplotype and Dirofilaria ursi as outgroups of the clusters of D. repens and Dirofilaria immitis, which are the causal agents of most human dirofilariasis. As like bear filaria D. ursi, a wide variety of other carnivore-parasitizing filaria species have rarely been reported in humans. The newly detected genetic haplotype in this case may correspond to one of these species of Dirofilaria, though the genetic references are not available thus far.

CD22 and CD72 cooperatively contribute to the development of the reverse Arthus reaction model.

BACKGROUND: Local type III hypersensitivity reactions are acute inflammatory events induced by immune complex (IC) deposition. CD22 and CD72 are B cell-specific cell surface molecules that negatively regulate B cell function. OBJECTIVE: To elucidate the roles of CD22 and CD72 in the development of IgG-mediated type III hypersensitivity reactions. METHOD: The reverse Arthus reaction model in the skin was induced in mice lacking CD22 (CD22-/-), CD72 (CD72-/-), and both of them (CD22-/-/CD72-/-). Edema at 4h and hemorrhage at 8h after IC challenge were evaluated. Inflammatory cell infiltration and cytokine and chemokine expression were also examined. RESULTS: Edema and hemorrhage were significantly reduced in CD22-/-/CD72-/- mice compared with wild-type mice. The loss of both membrane proteins resulted in a greater decrease in edema at 4h, but not hemorrhage at 8h, than the loss of each protein alone. Infiltration of neutrophils, macrophages, and T cells, and the expression of TNF-α, IL-6, MIP-1α, and CCR5 mRNA were also diminished in the knockout mice compared to wild-type mice, and most significantly reduced in CD22-/-/CD72-/- mice. Regulatory T (Treg) cells in the spleen were significantly increased in all knockout mice at 4h. Significant differences in the severity of edema and hemorrhage between wild-type and knockout mice were lost when Treg cells were depleted in the knockout mice. CONCLUSION: These results demonstrate that CD22 and CD72 expression contribute to the development of the reverse Arthus reaction model and CD22 and CD72 might be therapeutic targets for human IC-mediated diseases.

Regulatory B1a Cells Suppress Melanoma Tumor Immunity via IL-10 Production and Inhibiting T Helper Type 1 Cytokine Production in Tumor-Infiltrating CD8+ T Cells.

In tumor immunity, the participation of IL-10-producing regulatory B cells (Bregs), which play an important role in suppressing immune responses, is unclear. In this study, we demonstrated an increase in B16F10 melanoma growth and a decrease in the proportion of IFN-γ- and TNF-α-secreting tumor-infiltrating CD8+ T cells in B cell-specific PTEN-deficient mice in which Bregs were expanded. The number of tumor-infiltrating Bregs significantly increased in B cell-specific PTEN-deficient mice. More than 50% of tumor-infiltrating B cells consisted of Bregs, predominantly CD19+CD5+CD43+ B1a Bregs, in both B cell-specific PTEN-deficient and control mice. Adoptive B1a B cell transfer, which includes >30% of Bregs, increased melanoma growth, whereas non-B1a B cell transfer, which includes <2% of Bregs, exhibited no effect. In addition, adoptive transfer of B1a B cells from wild-type mice, but not IL-10-/- mice, exacerbated B16F10 melanoma growth. The current study indicates that B1a Bregs negatively regulate anti-melanoma immunity by producing IL-10 and reducing T helper 1 type cytokine production in tumor-infiltrating CD8+ T cells. Therefore, B1a Bregs can be a potentially novel target for immunotherapy of melanomas.

Increased expression levels of FcγRIIB on naïve and double-negative memory B cells in patients with systemic sclerosis.

OBJECTIVES: In systemic sclerosis (SSc), B cell hyperactivation and abnormality are considered to play an important role in the disease pathophysiology. We aimed to clarify if the abnormal activation of B cells involves inhibitory FcγRIIB on B cells in SSc patients. METHODS: Blood samples were collected from 76 SSc patients (38 limited cutaneous SSc and 38 diffuse cutaneous SSc) and 59 healthy controls. We evaluated the expression levels of FcγRIIB on different B cell subsets. B cells were classified into five subsets based on their surface phenotype as measured by flow cytometry: naïve B cells (CD19+IgD+CD27-), pre-switched memory B cells (CD19+IgD+CD27+), double-negative (DN) memory B cells (CD19+IgD-CD27-), switched memory B cells (CD19+IgD-CD27mid), and plasmablasts (CD19+IgD-CD27high). The expression levels of the activation markers CD80, CD86, and CD95 were also examined. RESULTS: The expression levels of FcγRIIB on SSc naïve and DN memory B cells were significantly increased compared to healthy controls (p<0.05 and p<0.001, respectively). CD80, CD86, and CD95 expression levels were significantly higher in all five B cell subsets, except for CD80 in switched memory B cells and plasmablasts. Increased FcγRIIB expression levels on DN memory B cells were associated with disease activity as assessed by the European Scleroderma Study Group Activity Index, presence of interstitial lung disease (ILD), and reduced lung function. Intravenous cyclophosphamide pulse therapy decreased FcγRIIB expression levels on memory B cell subsets. CONCLUSIONS: SSc B cells may exhibit compensatory elevation in the expression levels of FcγRIIB in order to suppress the abnormal activation of B cells. In addition, FcγRIIB expression levels may serve as a marker of severe complications, such as ILD, in SSc.

BAFF inhibition attenuates fibrosis in scleroderma by modulating the regulatory and effector B cell balance.

Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and lung fibrosis. More than 90% of patients with SSc are positive for autoantibodies. In addition, serum B cell activating factor (BAFF) level is correlated with SSc severity and activity. Thus, B cells are considered to play a pathogenic role in SSc. However, there are two opposing subsets: regulatory B cells (Bregs) and effector B cells (Beffs). Interleukin-10 (IL-10)-producing Bregs negatively regulate the immune response, while IL-6-producing Beffs positively regulate it. Therefore, a protocol that selectively depletes Beffs would represent a potent therapy for SSc. The aims of this study were to investigate the roles of Bregs and Beffs in SSc and to provide a scientific basis for developing a new treatment strategy targeting B cells. A bleomycin-induced scleroderma model was induced in mice with a B cell-specific deficiency in IL-6 or IL-10. We also examined whether BAFF regulates cytokine-producing B cells and its effects on the scleroderma model. IL-6-producing Beffs increased in number and infiltrated the inflamed skin in the scleroderma model. The skin and lung fibrosis was attenuated in B cell-specific IL-6-deficient mice, whereas B cell-specific IL-10-deficient mice showed more severe fibrosis. In addition, BAFF increased Beffs but suppressed Bregs. Furthermore, BAFF antagonist attenuated skin and lung fibrosis in the scleroderma model with reduction of Beffs but not of Bregs. The current study indicates that Beffs play a pathogenic role in the scleroderma model, while Bregs play a protective role. BAFF inhibition is a potential therapeutic strategy for SSc via alteration of B cell balance.

Diagnostic criteria, severity classification and guidelines of eosinophilic fasciitis.

We established diagnostic criteria and severity classification of eosinophilic fasciitis because there is no established diagnostic criteria or widely accepted severity classification of the disease. Also, there has been no clinical guideline for eosinophilic fasciitis, so we established its clinical guideline ahead of all over the world. In particular, the clinical guideline was established by clinical questions based on evidence-based medicine according to the New Minds Clinical Practice Guideline Creation Manual (version 1.0). We aimed to make the guideline easy to use and reliable based on the newest evidence, and to present guidance as specific as possible for various clinical problems in treatment of eosinophilic fasciitis.