Clinical features of patients with connective tissue disease with anti-human upstream binding factor antibodies: A single-center retrospective study.

Anti-human upstream-binding factor (anti-hUBF) antibodies have been reported predominantly in patients with connective tissue diseases (CTDs); these have also been reported in patients without CTDs such as hepatocellular carcinoma. Because of the low frequency of expression and few case reports, there is no consensus on the clinical significance of these antibodies. Thus, we aimed to examine the clinical features of patients with anti-hUBF antibodies and analyzed 1042 patients with clinically suspected CTDs. The presence of anti-hUBF antibodies was screened using immunoprecipitation assays. Of the 1042 patients, 19 (1.82%) tested positive for anti-hUBF antibodies; among them, 10 (56%) were diagnosed with undifferentiated CTD (UCTD), six with systemic sclerosis (SSc) and three with other diseases. Five of the 10 patients with UCTD were referred to our hospital with suspected SSc. None of the five patients fulfilled the 2013 American College of Rheumatology/European League Against Rheumatism classification criteria, but three scored seven points, a relatively high score. Six anti-hUBF-positive patients with SSc had a significantly lower modified Rodnan skin score (mRSS) than that of anti-hUBF-negative patients with SSc (2 [0-2] vs 7 [0-49], p < 0.01). Compared with anti-topoisomerase I-positive patients, anti-hUBF-positive patients had a significantly lower mRSS (2 [0-2] vs 13 [0-42], p < 0.01) and lower incidence of scleroderma renal crisis (0 of 6 vs 8 of 184, p < 0.01). Compared with anti-centromere-positive patients, anti-hUBF-positive patients had a higher incidence of interstitial lung disease (ILD), but the difference was not statistically significant (4 of 6 vs 19 of 239). In conclusion, anti-hUBF antibodies were predominantly detected in patients with CTDs and UCTD. In patients with CTDs, SSc exhibited a high ratio, displaying a lower mRSS and higher incidence of ILD. In patients with UCTD, careful follow-up is recommended as they may develop CTDs in the future.

Absence of interstitial lung disease at initial visit may predict a favorable outcome for Japanese patients with systemic sclerosis with anti-topoisomerase I antibody.

Interstitial lung disease (ILD) is recognized a prognostic factor and leading cause of death in patients with systemic sclerosis (SSc). The aim of the present study is to clarify factors at an initial visit that are associated with the deterioration of ILD in SSc patients with anti-topoisomerase I (anti-topo I) antibodies. This was a single-center, retrospective, observational study. Fifty-three consecutive SSc patients with anti-topo I antibodies were included in this study. Of the 53 patients, 43 had ILD at their initial visit, whereas 10 did not. We examined the clinical and immunological factors at an initial visit that were associated with the deterioration of ILD. The deterioration of ILD was defined as the administration of intravenous cyclophosphamide (IVCY) therapy. In this cohort, 45 (85%) patients had ILD at the time of the final observation, and only two who did not have ILD at their initial visit developed ILD during the follow-up period. Until the final observation, 26 (49%) patients received IVCY therapy for the progression of ILD. The age at onset, disease duration, SSc subtype, and skin score were similar between patients with and those without IVCY therapy. Approximately 60% (26 of 43) of patients with ILD at their initial visit received IVCY therapy. On the other hand, none of the 10 patients without ILD at their initial visit received IVCY therapy. Our multivariate analyses using Cox proportional hazards regression model revealed that the presence of ILD at an initial visit was an independent factor associated with the introduction of IVCY therapy (odds ratio, 2.8e+7 [95% confidence interval, 1.8e+17-uncalculated], p = 0.0048). Although anti-topo I antibodies are strongly associated with ILD, it was unlikely for SSc patients with anti-topo I antibodies to receive IVCY therapy when they did not have ILD at an initial visit.

Patients with inflammatory myopathies overlapping with systemic sclerosis: A Brazilian-Japanese bicentric study.

Objectives: This study aims to describe and compare the demographic, clinical, and laboratory characteristics and follow-up of representative samples of patients with myopathies and systemic sclerosis overlap syndromes (Myo-SSc) from two tertiary centers. Patients and methods: This is a cross-sectional and retrospective study conducted between January 2000 and December 2020. Fourty-five patients were analyzed with Myo-SSc (6 males, 39 females; mean age: 50.2±15.4 years; range, 45 to 65 years) from two tertiary centers (n=30 from Brazil and n=15 from Japan). Results: The median follow-up was 98 (range, 37 to 168) months. Muscle impairment started simultaneously with the diagnosis of systemic sclerosis in 57.8% (26/45) of cases. Muscle involvement occurred before the onset of systemic sclerosis in 35.5% (16/45) of cases, and after in 6.7% (3/45). Polymyositis was observed in 55.6% (25/45) of cases, followed by dermatomyositis in 24.4% (11/45) and antisynthetase syndrome in 20.0% (9/45). Concerning systemic sclerosis, the diffuse and limited forms occurred in 64.4% (29/45) and 35.6% (16/45) of the cases, respectively. Comparing the subgroups, Myo or SSc onset was earlier in Brazilian patients, and they had a higher frequency of dysphagia (20/45, [66.7%]) and digital ulcers (27/45, [90%]), whereas Japanese patients had higher modified Rodnan skin scores (15 [9 to 23]) and prevalence of positive anti-centromere antibodies (4/15 [23.7%]). The current disease status and mortality were similar in both groups. Conclusion: In the present study, Myo-SSc affected middle-aged women, and its manifestation spectrum varied according to geographic distribution.

Longitudinal changes in nailfold videocapillaroscopy findings differ by myositis-specific autoantibody in idiopathic inflammatory myopathy.

OBJECTIVE: To assess the longitudinal changes in nailfold videocapillaroscopy (NVC) in patients expressing myositis-specific autoantibodies [anti-aminoacyl-tRNA synthetase (ARS), anti-transcriptional intermediary factor 1 (TIF1), and anti-melanoma differentiation-associated gene 5 (MDA5)]. METHODS: This study was performed retrospectively, at a single site, on an observational cohort. Seventy-one idiopathic inflammatory myopathy patients were included (25 patients expressed anti-MDA5 Abs, 24 patients expressed anti-TIF1 Abs, and 22 patients expressed anti-ARS Abs). NVC findings included giant, enlarged, and reduced capillaries, haemorrhages, capillary ramification, disorganization of the vascular array, and capillary loss. NVC findings were compared from baseline to after disease activity stabilization. RESULTS: The frequency of enlarged capillaries at baseline was different among the three groups, and was significantly higher in patients with anti-TIF1 Abs compared with those with anti-ARS Abs (88% vs 55%, P < 0.05). Reduced capillaries were significantly increased in patients with anti-TIF1 Abs compared with those with anti-MDA5 (96% vs 44%, P < 0.0001) or anti-ARS Abs (96% vs 50%, P < 0.0005). Both enlarged and reduced capillaries improved after stabilization in patients with anti-MDA5 Abs (P < 0.0001 and P < 0.05, respectively). These improvements were not observed in patients expressing anti-TIF1 and anti-ARS Abs. However, a significant reduction in haemorrhages was observed in all three groups (P < 0.0001 for each group). CONCLUSIONS: The results of this study demonstrate that longitudinal changes in NVC findings may vary depending on myositis-specific Ab expression. Therefore, it is crucial to assess individual NVC findings separately, as each finding may impact disease activity in a different manner.

FcγRIIB inhibits inflammation in a murine model of psoriasis.

BACKGROUND: Psoriasis is a chronic, inflammatory cutaneous disease. FcγRIIB is a low-affinity receptor for the IgG Fc fragment that provides a negative feedback pathway to down-regulate B-cell antigen receptor signaling. OBJECTIVE: The aim of this study was to investigate the role of FcγRIIB in the development of murine imiquimod (IMQ)-induced, psoriasis-like skin inflammation. METHODS: The experimental psoriasis-like skin inflammation was induced by the topical application of IMQ to the ears of FcγRIIB deficient (FcγRIIB-/-) and wild-type (WT) mice. After 6 days, epidermal thickness and inflammatory cell infiltration of the skin were histopathologically assessed and cytokine and chemokine expression levels were measured with RT-PCR. RESULTS: Skin inflammation was significantly worse in FcγRIIB-/- mice than WT mice. In the skin, the numbers of Gr-1+ neutrophils, CD11c+ dendritic cells, and Foxp3+ T cells were significantly higher in FcγRIIB-/- mice than WT mice. In the spleen, the numbers of CD25+Foxp3+ T cells and CD19+IL-10+ B cells were also significantly higher in FcγRIIB-/-mice than WT mice. The mRNA expression of Il-6, Il-17a, and Il-23a was significantly enhanced in FcγRIIB-/- mice. An adoptive transfer of splenic leukocytes from FcγRIIB-/- mice into WT mice also exacerbated skin inflammation compared to WT mice that received splenic leukocytes from WT mice. Intravenous immunoglobulin significantly reduced skin inflammation in WT mice, but this improvement was not observed in FcγRIIB-/- mice. CONCLUSION: These results indicate that FcγRIIB likely plays a suppressive role in IMQ-induced, psoriasis-like skin inflammation. Furthermore, signal modulation via FcγRIIB is a potential therapeutic target for psoriasis.

Cytokine-producing B-cell balance associates with skin fibrosis in patients with systemic sclerosis.

Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and lung fibrosis. Over 90% of patients with SSc are positive for autoantibodies. In addition, the serum levels of B-cell activating factor, a potent B-cell stimulator, are correlated with SSc severity and activity. Thus, B cells play an important role in SSc pathogenesis. However, two opposing B-cell subsets exist: effector B cells (Beff) and regulatory B cells (Breg). Interleukin (IL)-6-producing Beff have been shown to promote scleroderma in a mouse model, whereas IL-10-producing Breg inhibit scleroderma development. In the present study, we investigated the clinical association of effector and regulatory B cells in patients with SSc. The blood levels of IL-6-producing Beff and IL-10-producing Breg were measured in 30 patients with SSc and 21 healthy subjects by flow cytometry. The frequency of IL-6-producing Beff in the blood was significantly (p < 0.0001) elevated in patients with SSc (median, 56.2%; range, 35.3-81.3%) compared with that in healthy controls (median, 41.3%; range, 21.0-61.3%). In contrast, the frequency of IL-10-producing Breg in the blood was significantly (p < 0.05) decreased in patients with SSc (median, 1.4%; range, 0.5-2.8%) compared with that in healthy controls (median, 2.0%; range, 1.1-3.8%). The Beff/Breg ratio was significantly increased in patients with SSc. In addition, the Beff/Breg ratio was positively correlated with the skin score and extent of interstitial lung disease. These results suggest that dysregulation of effector and regulatory B-cell balance contributes to SSc pathogenesis.

Oral Corticosteroids Impair Mucin Production and Alter the Posttransplantation Microbiota in the Gut.

INTRODUCTION: Gut microbiota alterations cause inflammation in patients with ulcerative colitis (UC). Fecal microbiota transplantation (FMT) enables manipulating the microbiota's composition, but the mechanisms underlying colonization of the posttransplantation microbiota are poorly understood. METHODS: In this open-label, nonrandomized study, the FMT efficacy and changes in the gut microbiota were evaluated in 8 UC patients with mild-to-moderately active endoscopic colonic lesions. Compositional changes in the fecal and mucosal microbiotas between donors and recipients were examined via 16S rRNA-based sequencing. To investigate the effects of oral corticosteroids on microbiota colonization, FMT was performed in germ-free prednisolone (PSL)-administered mice to examine the factors determining colonization. RESULTS: Four UC patients achieved clinical remission (CR) after FMT, and 3 also achieved endoscopic remission. The fecal microbiotas of the CR patients changed similar to those of the donors after FMT. The mucin-coding gene, MUC2, was less expressed in the colons of the PSL-dependent patients than in the PSL-free patients. In the mice, PSL treatment decreased the fecal mucin production and altered the posttransplantation fecal microbiota composition. Adding either exogenous mucin or the mucin secretagogue, rebamipide, partially alleviated the PSL-induced dysbiosis of the gut microbiota. Administering rebamipide with FMT from healthy donors relieved inflammation in mice with Enterococcus faecium-induced colitis. CONCLUSION: Colonic mucin controlled the gut microbiota composition, and oral corticosteroid treatment modified the gut microbiota partly by reducing the colonic mucin.

Drug-induced scleroderma-like lesion.

Drug-induced scleroderma-like lesion is a condition in which administration of a drug induces skin sclerotic lesions similar to systemic sclerosis or morphea. The clinical manifestations of drug-induced scleroderma-like lesion can be divided into two types: scleroderma-like lesions and morphea-like plaques. A wide variety of drugs can cause drug-induced scleroderma-like lesion. Bleomycin, L-tryptophan, vinyl chloride, and phytonadione (vitamin K1) have been reported, but in recent years, cases due to chemotherapeutic agents, such as taxane-based agents, gemcitabine, and tegafur-uracil, and immune checkpoint inhibitors have increased. Drug-induced scleroderma-like lesion differs from systemic sclerosis in that it does not include Raynaud's phenomenon, nail-fold capillary abnormality, organ involvement, such as reflux esophagitis, interstitial pneumonia, renal crisis, or anti-nuclear Abs. On the other hand, there are reports of cases in which Raynaud's phenomenon, positive conversion of anti-nuclear Abs, and development of skin sclerosis from the fingers developed after initiation of the drug. Whether the skin sclerosis improves after discontinuation of the drug depends on the patient. In patients with severe skin sclerosis, functional impairment, such as flexion contracture of the fingers, may occur, and systemic therapy, such as steroids, may be necessary. When treating patients with skin sclerosis, it is important to keep in mind the possibility that the sclerotic lesion may be induced by a drug.

Chest computed tomography findings of adult patients with antimelanoma differentiation-associated protein 5 antibody-positive interstitial lung disease.

OBJECTIVES: Interstitial lung disease (ILD) associated with the antimelanoma differentiation-associated protein 5 (anti-MDA5) antibody is a rapidly progressive disease that requires timely, aggressive treatment. However, prompt diagnosis is difficult due to the longer time required for antibody detection. This study described the computed tomography (CT) findings of anti-MDA5 antibody-positive ILD (anti-MDA5-ILD). METHODS: CT findings of 20 patients (7 men, 13 women; mean age, 53.6 ± 13.5 years) with anti-MDA5-ILD were retrospectively reviewed. All patients had clinical diagnoses of dermatomyositis, and 14 patients presented with amyopathic findings. RESULTS: Bilateral ground-glass attenuation, air-space consolidation, and reticular shadows were observed in 20 (100%), 15 (75%), and 3 (15%) patients, respectively. The spread of air-space consolidation was 6.0 ± 5.6% (mean ± standard deviation). Univariate analysis revealed that high Krebs von den Lungen-6, high spread of consolidation, low partial pressure of oxygen, and low forced vital capacity were significant predictors for poor survival. The final radiological diagnoses were nonspecific interstitial pneumonia and organising pneumonia (OP) in 2 (10%) and 16 (80%) patients, respectively. Further, 30% of OP patients showed fibrosis. CONCLUSION: The characteristic CT findings of patients with anti-MDA5-ILD were ground-glass attenuation, air-space consolidation, and less reticulation. These CT findings were compatible with those of OP.

Cell surface-expressed Ro52/IgG/HLA-DR complex is targeted by autoantibodies in patients with inflammatory myopathies.

Intracellular proteins are often targeted by autoantibodies in autoimmune diseases; however, the mechanism through which intracellular molecules are targeted remains unknown. We previously found that several intracellular misfolded proteins are transported to the cell surface by HLA class II molecules and are recognized by autoantibodies in some autoimmune diseases, such as rheumatoid arthritis, antiphospholipid syndrome, and microscopic polyangiitis. Ro52 is an intracellular Fc receptor that is a target antigen for myositis-associated autoantibodies. We analyzed the role of HLA class II molecules in the autoantibody recognition of Ro52. Ro52 alone was not transported to the cell surface by HLA class II molecules; however, it was transported to the cell surface in the presence of both IgG heavy chain and HLA class II molecules to form a Ro52/IgG/HLA-DR complex. The Ro52/IgG/HLA-DR complex was specifically recognized by autoantibodies from some patients with inflammatory myopathies. We then evaluated 120 patients with inflammatory myopathies with four types of myositis-specific antibodies and analyzed the autoantibodies against the Ro52/IgG/HLA-DR complex. The specific antibodies against the Ro52/IgG/HLA-DR complex were detected in 90% and 93% of patients who were positive for anti-MDA5 and anti-ARS antibodies, respectively. In individual patients with these two inflammatory myopathies, changes in serum titers of anti-Ro52/IgG/HLA-DR-specific antibodies were correlated with the levels of KL-6 (R = 0.51 in anti-MDA5 antibody-positive DM patients, R = 0.67 in anti-ARS antibody-positive PM/DM patients with respiratory symptoms) and CK (R = 0.63 in anti-ARS antibody-positive PM/DM patients with muscle symptoms) over time. These results suggest that antibodies against Ro52/IgG/HLA-DR expressed on the cell surface could be involved in the pathogenesis of inflammatory myopathy subgroups.

A role for FcγRIIB in the development of murine bleomycin-induced fibrosis.

BACKGROUND: Systemic sclerosis (SSc) is a systemic autoimmune disease characterized by excessive fibrosis. FcγRIIB is a low-affinity receptor for the Fc fragment of IgG. FcγRIIB is expressed on the surface of various leukocyte subsets and signals negative feedback pathways to down-regulate B-cell antigen receptor signaling. OBJECTIVE: The aim of the present study was to investigate the role of FcγRIIB in the development of a murine bleomycin-induced scleroderma model. METHODS: The experimental fibrosis model was generated by the intradermal injection of bleomycin into wild-type (WT) and FcγRIIB-deficient (FcγRIIB-/-) mice. We histologically assessed skin and lung fibrosis as well as inflammatory cell infiltration. Cytokine and chemokine expression levels were measured with RT-PCR. RESULTS: The severity of fibrosis in the skin and lung was significantly worse in FcγRIIB-/- mice than in WT mice. In the skin of bleomycin-treated mice, the numbers of CD8+ T cells, F4/80+ macrophages, MPO+ neutrophils, NK1.1+NK cells, and B220+ B cells were significantly higher in FcγRIIB-/- mice than in WT mice. The expression of TNF-α and IL-1ß was significantly higher in FcγRIIB-/- mice than in WT mice as was the expression of ICAM-1, CXCL2, and CCL3 in the affected skin. An adoptive transfer of splenic leukocytes from FcγRIIB-/- mice into WT mice showed exacerbated skin and lung fibrosis compared to WT mice without an adoptive transfer. CONCLUSION: These results indicate that FcγRIIB plays an inhibitory role in skin and lung fibrosis. Moreover, modulating FcγRIIB signaling has potential as a therapeutic approach for SSc.

[Anti-nuclear matrix protein 2 antibody-positive dermatomyositis with the preferential involvement of neck extensors: a case report].

A 68-year-old man with a 2-month history of progressive weakness and spontaneous pain in proximal limb muscles presented to our hospital with a dropped head. He started experiencing progressive dysphagia several days before admission. On admission, he had muscle weakness of the limbs and neck extensors with edema and induration in distal extremities. Laboratory tests showed elevation of muscle enzymes. FDG-PET/CT demonstrated multiple hypermetabolic lymph nodes, but the primary site was not identified; thus, metastatic carcinoma of unknown primary origin was considered. The patient was diagnosed with anti-nuclear matrix protein 2 antibody-positive paraneoplastic myopathy based on serum tests. Histological findings of the left biceps brachii muscle biopsy revealed severe variation in fiber size and perifascicular myofiber atrophy. Myofibers exhibited myxovirus resistance protein A expression predominantly in the perifascicular region. Following intravenous methylprednisolone pulse therapy and intravenous immunoglobulin, the patient's muscle strength improved with normalization of muscle enzyme levels. The dropped head was considered to have resulted from the preferential involvement of neck extensors based on the observed FDG-PET/CT uptake in neck extensors.

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.