Case report: Presumptive subcutaneous malignant peripheral nerve sheath tumor with intracranial invasion and osteolysis in the posterior fossa of a dog.

A 13-year-old castrated male Toy Poodle presented with an acute vestibular disorder. Magnetic resonance imaging and computed tomography revealed a large oval space-occupying mass with skull destruction located from the subcutaneous tissue to the posterior fossa region. Histopathologically, the mass was a bundled growth of spindle-shaped mesenchymal tumor cells between the myofibrillar and collagen bundles. The cells were moderately irregular in size and had eosinophilic stained cytoplasm. The cells were highly atypical and had rare mitotic figures. Neoplastic cells were immunoreactive for S100, GFAP, Olig-2, SOX10 and immunonegative for NF, E-cadherin, and Claudin-1. Collective findings were presumptive with a diagnosis of malignant peripheral nerve sheath tumor.

Serum gasdermin D levels are associated with the chest computed tomography findings and severity of COVID-19.

BACKGROUND: The role of programmed cell death, especially pyroptosis and apoptosis, in unfavorable immune responses in COVID-19 remains to be elucidated. METHODS: We conducted a cross-sectional analysis to investigate the association between the serum gasdermin D (GSDMD) levels, a pyroptotic marker, and caspase-cleaved cytokeratin 18 fragment (M30), an apoptotic marker, and the clinical status and abnormal chest computed tomography (CT) findings in patients with COVID-19. RESULTS: In this study, 46 patients diagnosed with COVID-19 were divided into the following three groups according to the disease severity: mild to moderate group (n = 10), severe group (n = 14), and critical group (n = 22). The serum GSDMD levels were higher in the critical group than in the mild to moderate group (P = 0.016). In contrast, serum M30 levels were lower in the critical group than in the severe group (P = 0.048). Patients who required mechanical ventilation or died had higher serum GSDMD levels than those who did not (P = 0.007). Area of consolidation only and of ground glass opacity plus consolidation positively correlated with serum GSDMD levels (r = 0.56, P < 0.001 and r = 0.53, P < 0.001, respectively). CONCLUSION: Higher serum GSDMD levels are associated with critical respiratory status and the consolidation area on chest CT in patients with COVID-19, suggesting that excessive activation of pyroptosis may affect the clinical manifestations in patients with COVID-19.

Serum polyethylene glycol-specific IgE and IgG in patients with hypersensitivity to COVID-19 mRNA vaccines.

BACKGROUND: The mechanism of allergic reactions to COVID-19 mRNA vaccines has not been clarified. Polyethylene glycol (PEG) is a potential antigen in the components of vaccines. However, there is little evidence that allergy after COVID-19 mRNA vaccination is related to PEG. Furthermore, the role of polysorbate (PS) as an antigen has also not been clarified. The objective of this study was to investigate whether PEG and PS allergies are reasonable causes of allergic symptoms after vaccination by detecting PEG-specific and PS-specific antibodies. METHODS: Fourteen patients who developed immediate allergic reactions to BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccines and nineteen healthy controls who did not present allergic symptoms were recruited. Serum PEG-specific immunoglobulin E (IgE) and immunoglobulin G (IgG) and PS-specific IgE and IgG were measured by enzyme-linked immunosorbent assay. Skin tests using PEG-2000 and PS-80 were applied to five patients and three controls. RESULTS: Serum levels of PEG-specific IgE and IgG in patients with immediate allergic reactions to the COVID-19 mRNA vaccine were higher than those in the control group. Serum levels of PS-specific IgE in patients with allergy to the vaccine were higher than those in patients of the control group. Intradermal tests using PEG verified the results for PEG-specific IgE and IgG. CONCLUSIONS: The results suggest that PEG is one of the antigens in the allergy to COVID-19 mRNA vaccines. Cross-reactivity between PEG and PS might be crucial for allergy to the vaccines. PEG-specific IgE and IgG may be useful in diagnosing allergy to COVID-19 mRNA vaccines.

DOCK8-expressing T follicular helper cells newly generated beyond self-organized criticality cause systemic lupus erythematosus.

Pathogens including autoantigens all failed to induce systemic lupus erythematosus (SLE). We, instead, studied the integrity of host's immune response that recognized pathogen. By stimulating TCR with an antigen repeatedly to levels that surpass host's steady-state response, self-organized criticality, SLE was induced in mice normally not prone to autoimmunity, wherein T follicular helper (Tfh) cells expressing the guanine nucleotide exchange factor DOCK8 on the cell surface were newly generated. DOCK8+Tfh cells passed through TCR re-revision and induced varieties of autoantibody and lupus lesions. They existed in splenic red pulp and peripheral blood of active lupus patients, which subsequently declined after therapy. Autoantibodies and disease were healed by anti-DOCK8 antibody in the mice including SLE-model (NZBxNZW) F1 mice. Thus, DOCK8+Tfh cells generated after repeated TCR stimulation by immunogenic form of pathogen, either exogenous or endogenous, in combination with HLA to levels that surpass system's self-organized criticality, cause SLE.

COVID-19 and adult-onset Still's disease as part of hyperferritinemic syndromes.

The coronavirus disease (COVID-19) is known to cause hyperferritinemia and haemophagocytic lymphohistiocytosis. Including this laboratory parameter, symptoms similar to COVID-19 have been observed in adult-onset Still's disease (AOSD), catastrophic antiphospholipid syndrome, macrophage activation syndrome, and septic shock, which has led to the proposal of a concept called 'hyperferritinemic syndromes'. High levels of some clinical markers in both COVID-19 and AOSD make them difficult to differentiate. While the efficacy of ciclesonide had been expected for mild pneumonia with COVID-19, the efficacy of tocilizumab (TCZ), which is a known treatment for AOSD, was not established. We report the first known occurrence of COVID-19 diagnosed in March 2020, preceded by the diagnosis of AOSD in April 2019. The patient was given prednisolone and TCZ, which led to remission. With the dyspnea and ground-glass appearance on chest computed tomography, PCR test revealed COVID-19 infection. Ciclesonide was started on Day 7 of the disease onset, which led to improved inflammatory markers. We infer that while TCZ is theoretically useful for COVID-19 due to its inhibition of interleukin 6. AOSD and COVID-19 may be differentiated by levels of ferritin, and appropriate treatment must be allocated.

Rheumatoid arthritis relapse in patients with other iatrogenic immunodeficiency-associated lymphoproliferative disorders and its treatment.

OBJECTIVES: Rheumatoid arthritis (RA) in patients undergoing immunosuppressive therapy (IS) is sometimes involved with other iatrogenic immunodeficiency-associated lymphoproliferative disorders (LPD). We aimed to clarify the effects of LPD treatment on RA and the current status of RA treatment options after LPD onset and subsequent IS withdrawal. METHODS: We retrospectively analyzed data of patients who had RA with LPD and examined the relationship between LPD course and RA treatment as well as that between RA relapse and LPD treatment. RESULTS: LPD patients were categorized into two groups: patients who regressed spontaneously (n = 19) and those who needed chemotherapy (n = 12). The chemotherapy group had significantly less RA relapse than the spontaneous regression group (p = .041). RA almost relapsed early in the spontaneous regression group and needed treatment for RA. Chemotherapy with rituximab prevented long-term RA relapse, and RA did not relapse for long even after rituximab monotherapy. The total dose of rituximab in monotherapy correlated with the time to RA relapse. Six patients with RA relapse received biologics and had no LPD relapse for more than 1 year. CONCLUSIONS: Rituximab in chemotherapy for LPD may help prevent RA relapse with LPD. Large-scale studies are required in the future for verification.

Conditional Upregulation of IFN-α Alone Is Sufficient to Induce Systemic Lupus Erythematosus.

The cause of systemic lupus erythematosus (SLE) is unknown. IFN-α has been suggested as a causative agent of SLE; however, it was not proven, and to what extent and how IFN-α contributes to the disease is unknown. We studied the contribution of IFN-α to SLE by generating inducible IFN-α transgenic mice and directly show that conditional upregulation of IFN-α alone induces a typical manifestation of SLE in the mice not prone to autoimmunity, such as serum immune complex, autoantibody against dsDNA (anti-dsDNA Ab), and the organ manifestations classical to SLE, such as immune complex-deposited glomerulonephritis, classical splenic onion-skin lesion, alopecia, epidermal liquefaction, and positive lupus band test of the skin. In the spleen of mice, activated effector CD4 T cells, IFN-γ-producing CD8 T cells, B220+CD86+ cells, and CD11c+CD86+ cells were increased, and the T cells produced increased amounts of IL-4, IL-6, IL-17, and IFN-γ and decreased IL-2. In particular, activated CD3+CD4-CD8- double-negative T cells positive for TCRαß, B220, CD1d-teteramer, PD-1, and Helios (that produced increased amounts of IFN-γ, IL-4, IL-17, and TNF-α) were significantly expanded. They infiltrated into kidney and induced de novo glomerulonephritis and alopecia when transferred into naive recipients. Thus, sole upregulation of IFN-α is sufficient to induce SLE, and the double-negative T cells expanded by IFN-α are directly responsible for the organ manifestations, such as lupus skin disease or nephritis.

CD4+CD25+LAG3+ T Cells With a Feature of Th17 Cells Associated With Systemic Lupus Erythematosus Disease Activity.

Systemic lupus erythematosus (SLE) is an autoimmune disease that involves multiple immune cell subsets. We analyzed immune cell subsets in human peripheral blood mononuclear cells (PBMC) in order to identify the cells that are significantly associated with SLE disease activity and treatment. The frequencies of various subsets of CD4+ T cells, B cells, monocytes and NK cells in PBMC were assessed in 30 healthy controls (HC), 30 rheumatoid arthritis (RA) patients and 26 SLE patients using flow cytometry. The correlations between subset frequencies in SLE and clinical traits including Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) were examined. Changes in subset frequencies after the treatment in SLE patients were investigated. We focused on CD25+LAG3+ T cells and investigated their characteristics, including cytokine secretion, mRNA expression and suppression capacity. We assessed correlations between CD25+LAG3+ T cells and SLEDAI by Spearman's rank correlation coefficient. CD25+LAG3+ T cells were significantly increased in SLE whereas there were few in RA and HC groups. CD25+LAG3+ T cell frequencies were significantly correlated with SLEDAI and were increased in patients with a high SLEDAI score (> 10). CD25+LAG3+ T cells produced both IL-17 and FOXP3, expressed mRNA of both FOXP3 and RORC and lacked suppressive capacity. CD25+LAG3+ T cells were associated with disease activity of SLE. CD25+LAG3+ T cells had features of both CD25+FOXP3+ regulatory T cells (CD25+ Treg) and Th17. CD25+LAG3+ T cells could be associated with the inflammatory pathophysiology of SLE.

Postprandial Blood Pressure Decrease in Patients with Type 2 Diabetes and Mild or Severe Cardiac Autonomic Dysfunction.

Background Few reports have evaluated the relationship between changes in postprandial blood pressure and the severity of autonomic dysfunction in patients with type 2 diabetes. This was a cross-sectional study designed to investigate postprandial blood pressure changes in individuals without type 2 diabetes and patients with type 2 diabetes and mild or severe cardiac autonomic dysfunction. Methods Forty patients with type 2 diabetes mellitus and 20 individuals without type 2 diabetes participated in this study. Fifty-two participants underwent a meal tolerance test. Blood pressure (brachial systolic blood pressure (bSBP) and central systolic blood pressure (cSBP)), electrocardiogram recordings, and blood samples were assessed before and after meal ingestion. Patients with diabetes were divided into two groups based on their coefficient of variation of R⁻R intervals (CVRR): a normal or mildly dysfunctional group (mild group, CVRR ≥ 2%; n = 20) and a severely dysfunctional group (severe group, CVRR < 2%; n = 15). Results In the control group, bSBP and cSBP did not significantly change after meal ingestion, whereas both decreased significantly at 60 min after meal ingestion in the mild and severe groups. While blood pressure recovered at 120 min after meal ingestion in the mild group, a significant decrease in blood pressure persisted at 120 min after meal ingestion in the severe group. Conclusions Based on these results, adequate clinical attention should be paid to the risk of serious events related to postprandial decreases in blood pressure, particularly in patients with diabetes and severe cardiac autonomic dysfunction.

HLA-DRB1 Shared Epitope Alleles and Disease Activity Are Correlated with Reduced T Cell Receptor Repertoire Diversity in CD4+ T Cells in Rheumatoid Arthritis.

OBJECTIVE: Shared epitope (SE) alleles are the most significant genetic susceptibility locus in rheumatoid arthritis (RA); however, their target populations in CD4+ T cells are not well elucidated. We analyzed the association between SE alleles and the T cell receptor (TCR) repertoire diversity of naive and memory CD4+ T cells using next-generation sequencing (NGS). METHODS: The TCR beta chains in naive and memory CD4+ T cells from the peripheral blood of 22 patients with RA and 18 age- and sex-matched healthy donors (HD) were analyzed by NGS. The Renyi entropy was used to evaluate TCR repertoire diversity and its correlations with SE alleles and other variables were examined. Serum cytokine levels were measured by multiplex ELISA. RESULTS: The TCR repertoire diversity in memory CD4+ T cells was reduced in SE allele-positive patients with RA compared with HD, and showed a significant negative correlation with the SE allele dosage in RA. The TCR repertoire diversity of naive and memory T cells was also negatively correlated with disease activity, and the SE allele dosage and disease activity were independently associated with reduced TCR repertoire diversity. TCR repertoire diversity showed a significant positive correlation with the serum interleukin 2 levels. CONCLUSION: SE alleles and disease activity were negatively correlated with the TCR repertoire diversity of CD4+ T cells in RA. Considering the pivotal role of CD4+ T cells in RA, restoring the altered TCR repertoire diversity will provide a potential RA therapeutic target.

Scleritis Associated with SAPHO Syndrome: A Case Report.

A 31-year-old woman developed bilateral painful red eyes. A slit-lamp examination revealed anterior diffuse scleritis. She had been diagnosed with palmoplantar pustulosis 2 years before. Further evaluation revealed hyperostosis of the sacroiliac joint and inflammation of the bilateral sternoclavicular joints and right sternocostal joint. Ultimately, she was diagnosed with SAPHO syndrome by rheumatologists after excluding other causative diseases. Scleritis associated with SAPHO syndrome is relatively uncommon. An identification of any systemic symptoms and early consultation with rheumatologists are key to making an early and correct diagnosis.

A gene module associated with dysregulated TCR signaling pathways in CD4+ T cell subsets in rheumatoid arthritis.

We analyzed the transcriptome of detailed CD4+ T cell subsets including them after abatacept treatment, and examined the difference among CD4+ T cell subsets and identified gene sets that are closely associated disease activity and abatacept treatment. Seven CD4+ T cell subsets (naive, Th1, Th17, Th1/17, nonTh1/17, Tfh and Treg) were sorted from PBMCs taken from 10 RA patients and 10 healthy controls, and three RA patients donated samples before and 6 months after abatacept treatment. Paired-end RNA sequencing was performed using HiSeq 2500. A total of 149 samples except for 12 outliers were analyzed. Overview of expression pattern of RA revealed that administration of abatacept exerts a large shift toward the expression pattern of HC. Most of differentially expressed gene (DEG) upregulated in RA (n = 1776) were downregulated with abatacept treatment (n = 1349). Inversely, most of DEG downregulated in RA (n = 1860) were upregulated with abatacept treatment (n = 1294). This DEG-based analysis revealed shared pathway changes in RA CD4+ T cell subsets. Knowledge-based pathway analysis revealed the upregulation of activation-related pathways in RA that was substantially ameliorated by abatacept. Weighted gene co-expression network analysis (WGCNA) evaluated CD4+ T cells collectively and identified a gene module that consisted of 227 genes and was correlated with DAS28-CRP (Spearman's rho = 0.46, p = 4 × 10-9) and abatacept administration (Spearman's rho = -0.91, p = 5 × 10-57). The most highly connected 30 genes of this module included ZAP70 and JAK3, and pathway analysis of this module revealed dysregulation of the TCR signaling pathway network, which was ameliorated by abatacept.

Increased serum concentrations of IL-1 beta, IL-21 and Th17 cells in overweight patients with rheumatoid arthritis.

BACKGROUNDS: Obesity is associated with worse disease activity and drug responses in patients with rheumatoid arthritis (RA). However, the immunological mechanisms responsible for the relationship between RA and obesity have not yet been clarified in detail. This study aimed to elucidate the immunological mechanisms contributing to the pathogenesis of RA in overweight patients. METHODS: The frequencies of CD4+ T cell, B cell and monocyte subsets were analyzed in RA (n = 81) and healthy donors (n = 99) by flow cytometry, and were compared between three groups (body mass index (BMI) <20, ≥20 to 25, >25). Serum cytokines were measured using multiplex ELISA. Gene expression was analyzed by quantitative PCR. Clinical information was extracted from medical records. RESULTS: The frequencies of T helper (Th)17 (CD4+CD45RA-CXCR5-CXCR3-CCR6+) cells and plasmablasts (PB) were significantly increased in patients with RA with BMI >25. Significant correlation was observed between BMI and Th17 cells in patients with RA. No significant differences in cell frequencies between the three BMI groups were observed in the healthy donors. Serum interleukin (IL)-1ß and IL-21 significantly correlated with BMI in RA patients. Gene expression patterns in Th17 cells from overweight patients with RA showed the characteristics of pathogenic Th17 cells. CONCLUSIONS: Quantitative and qualitative changes in Th17 cells were characteristic in overweight patients with RA.

Interleukin-10-producing LAG3+ regulatory T cells are associated with disease activity and abatacept treatment in rheumatoid arthritis.

BACKGROUND: Regulatory T cells (Tregs) play a role in the suppression of inflammation in autoimmune diseases, and lymphocyte activation gene 3 (LAG3) was reported as a marker of interleukin (IL)-10-producing Tregs. We aimed to clarify the function of human IL-10-producing CD4+CD25-LAG3+ T cells (LAG3+ Tregs) and their association with rheumatoid arthritis (RA). METHODS: LAG3+ Tregs of human peripheral blood mononuclear cells (PBMCs) were cultured with B cells and follicular helper T cells to examine antibody suppression effects. The frequency of LAG3+ Tregs was evaluated in peripheral blood samples from 101 healthy donors and 85 patients with RA. In patients treated with abatacept, PBMC samples were analyzed before and after treatment. Naive CD4+ T cells were sorted and cultured in the presence of abatacept, followed by flow cytometric analysis and function assays. RESULTS: LAG3+ Tregs produced high amounts of IL-10 and interferon-γ, and they suppressed B-cell antibody production more strongly than CD25+ Tregs. Cell-to-cell contact was required for the suppressive function of LAG3+ Tregs. The frequency of LAG3+ Tregs was lower in patients with RA, especially those with higher Clinical Disease Activity Index scores. LAG3+ Tregs significantly increased after 6 months of abatacept treatment, whereas CD25+ Tregs generally decreased. Abatacept treatment in vitro conferred LAG3 and EGR2 expression on naive CD4+ T cells, and abatacept-treated CD4+ T cells exhibited suppressive activity. CONCLUSIONS: IL-10-producing LAG3+ Tregs are associated with the immunopathology and therapeutic response in RA. LAG3+ Tregs may participate in a mechanism for the anti-inflammatory and immune-modulating effects of targeted therapy for costimulation.

Polygenic burdens on cell-specific pathways underlie the risk of rheumatoid arthritis.

Recent evidence suggests that a substantial portion of complex disease risk alleles modify gene expression in a cell-specific manner. To identify candidate causal genes and biological pathways of immune-related complex diseases, we conducted expression quantitative trait loci (eQTL) analysis on five subsets of immune cells (CD4+ T cells, CD8+ T cells, B cells, natural killer (NK) cells and monocytes) and unfractionated peripheral blood from 105 healthy Japanese volunteers. We developed a three-step analytical pipeline comprising (i) prediction of individual gene expression using our eQTL database and public epigenomic data, (ii) gene-level association analysis and (iii) prediction of cell-specific pathway activity by integrating the direction of eQTL effects. By applying this pipeline to rheumatoid arthritis data sets, we identified candidate causal genes and a cytokine pathway (upregulation of tumor necrosis factor (TNF) in CD4+ T cells). Our approach is an efficient way to characterize the polygenic contributions and potential biological mechanisms of complex diseases.

Enhanced gut homing receptor expression of unswitched memory B cells in rheumatoid arthritis.

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Immunophenotyping of rheumatoid arthritis reveals a linkage between HLA-DRB1 genotype, CXCR4 expression on memory CD4(+) T cells, and disease activity.

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that leads to destructive arthritis. Although the HLA class II locus is the strongest genetic risk factor for rheumatoid arthritis, the relationship between HLA class II alleles and lymphocyte activation remains unclear. We performed immunophenotyping of peripheral blood mononuclear cells on 91 HLA-DRB1-genotyped RA patients and 110 healthy donors. The frequency of memory CXCR4(+)CD4(+) T cells, and not Th1 and Th17 cells, was significantly associated with disease severity by multiple linear regression analysis. RA patients with one or more susceptible HLA-DR haplotypes (shared epitope: SE) displayed a significantly higher frequency of memory CXCR4(+)CD4(+) T cells. Moreover, the frequency of memory CXCR4(+)CD4(+) T cells significantly correlated with the expression level of HLA-DR on B cells, which was elevated in RA patients with SE. In vitro analysis and transcriptomic pathway analysis suggested that the interaction between HLA-DR and T cell receptors is an important regulator of memory CXCR4(+)CD4(+) T cells. Clinically, a higher frequency of memory CXCR4(+)CD4(+) T cells predicted a better response to CTLA4-Ig. Memory CXCR4(+)CD4(+) T cells may serve as a powerful biomarker for unraveling the linkage between HLA-DRB1 genotype and disease activity in RA.

Neuromyelitis optica spectrum disorder complicated with Sjogren syndrome successfully treated with tocilizumab: A case report.

A 38-year-old woman with relapsing longitudinal extensive transverse myelitis and Sjogren's syndrome (SS) was admitted with lower extremity muscle weakness. Studies showed high serum titer of anti-aquaporin4 antibody and gadolinium-enhanced-MRI T1-weighted lesions within thoracic cord. Clinical findings suggested neuromyelitis optica-spectrum disorder (NMO-SD). High-dose corticosteroids, plasma exchange and cyclophosphamide were not effective. After starting tocilizumab, her neurological findings gradually improved. This report describes the first evidence to show tocilizumab could be effective for NMO-SD with SS.