Analysis of Single-Cell Transcriptome and Surface Protein Expression in Ankylosing Spondylitis Identifies OX40-Positive and Glucocorticoid-Induced Tumor Necrosis Factor Receptor-Positive Pathogenic Th17 Cells.

OBJECTIVE: To demonstrate the immune landscape of blood and synovial cells in the setting of ankylosing spondylitis (AS) through the analysis of both single-cell transcriptome and surface protein expression, and to unveil the molecular characteristics of pathogenic Th17 cells. METHODS: This study included 40 individuals with active AS, 20 individuals with stable AS, 40 patients with active rheumatoid arthritis, and 20 healthy controls. Surface phenotype and intracellular staining were assessed using flow cytometry after peripheral blood mononuclear cells and synovial fluid mononuclear cells were stimulated with T cell receptor. Single-cell transcriptomes of 6 patients with active AS were studied along with cellular indexing of transcriptomes and epitopes by sequencing. We also assessed the outcome of targeting OX40 and glucocorticoid-induced tumor necrosis factor receptor (GITR) on the surface of Th17 cells in a mouse model of curdlan-injected SKG mice in which anti-GITR ligand and/or anti-OX40 ligand were used. RESULTS: We identified pathogenic Th17 cells as polyfunctional interleukin-17A (IL-17A)- and interferon-γ (IFNγ)-producing memory CD4+ T cells, with clinically supportive evidence for their pathogenic roles at sites of inflammation in AS. Transcriptome and flow cytometric analyses revealed that the coexpression of TNFRSF4 (OX40) and TNFRSF18 (GITR) is increased in pathogenic Th17 cells. Suppression of ligand receptor interactions in vivo through OX40 and GITR effectively suppressed clinical arthritis and decreased pathogenic Th17 cells in the curdlan-injected SKG mouse model. CONCLUSION: Our results have implications for the understanding of pathogenic Th17 cells in AS patients and suggest potential therapeutic targets.

Identification of Metabolic Signature Associated with Idiopathic Inflammatory Myopathy Reveals Polyamine Pathway Alteration in Muscle Tissue.

Idiopathic inflammatory myopathy (IIM) is hard to diagnose without a muscle biopsy. We aimed to identify a metabolite panel for IIM detection by metabolomics approach in serum samples and to explore the metabolomic signature in tissue samples from a mouse model. We obtained serum samples from IIM patients, ankylosing spondylitis (AS) patients, healthy volunteers and muscle tissue samples from IIM murine model. All samples were subjected to a targeted metabolomic approach with various statistical analyses on serum and tissue samples to identify metabolic alterations. Three machine learning methods, such as logistic regression (LR), support vector machine (SVM), and random forest (RF), were applied to build prediction models. A set of 7 predictive metabolites was calculated using backward stepwise selection, and the model was evaluated within 5-fold cross-validation by using three machine algorithms. The model produced an area under the receiver operating characteristic curve values of 0.955 (LR), 0.908 (RF) and 0.918 (SVM). A total of 68 metabolites were significantly changed in mouse tissue. Notably, the most influential pathways contributing to the inflammation of muscle were the polyamine pathway and the beta-alanine pathway. Our metabolomic approach offers the potential biomarkers of IIM and reveals pathologically relevant metabolic pathways that are associated with IIM.

Quantitative analysis of ataxic gait in patients with schizophrenia: the influence of age and visual control.

Previous research has determined that patients with schizophrenia classically exhibit ataxic gait. Age and visual controls of balance are important factors, and may influence gait, but have not been controlled. A total of 100 patients with schizophrenia were included in this study, along with 50 age- and sex-matched healthy controls. They were sampled with methods which stratified both groups according to age and sex. Tandem gait tests were conducted with eyes open and closed, and gait parameters were assessed by the footprint method. Ataxic gait was found to be significantly more frequent in the schizophrenic group. With eyes open, ataxic gait showed a significant increase with age in the schizophrenic group, but not in the healthy control group. Adjusting ataxic gait of the patients on the basis of the normal age effects measured in the healthy control group, the ataxic gait in the schizophrenic group increased according to age. Multiple logistic regression analysis revealed that old age and previous history of alcohol dependence/abuse were the risk factors for ataxic gait with eyes open. This implies that a dysfunction of the visuo-cerebellar circuit in patients with schizophrenia increases according to age.

No association found between 158 Val/Met polymorphism of the COMT gene and schizophrenia with minor physical anomalies.

The catechol-O-methyl transferase (COMT) gene has been a promising candidate in genetic research on schizophrenia because of its function in dopamine metabolism and its location on chromosome 22q11.2, which may be implicated in both schizophrenia and velocardiofacial syndrome (VCFS). To explore the possible genetic contribution of COMT to the development of schizophrenia, we focused on the subgroup of patients with schizophrenia characterized by minor physical anomalies as a phenotype and the 158 Val/Met polymorphism as a genotype. Since some physical anomalies are found in both schizophrenia and VCFS, schizophrenia patients with minor physical anomalies could represent the putative subgroup of schizophrenia linked to a disruption in neurodevelopment. Genotyping for the 158 Val/Met (472 G>A) polymorphism in the COMT gene was done for 239 patients with schizophrenia and 248 normal controls. Our analysis did not yield any significant between-group differences in terms of either allele or genotype frequency. We also could not find any association between the COMT gene and the schizophrenia subgroup with minor physical anomalies, although there was a significant difference in Waldrop total scores between the patients with schizophrenia and the normal controls. Analyses of subgroups based on other clinical variables also did not reveal significant differences. Overall, this study does not support the hypothesis that the 158 Val/Met polymorphism in the COMT gene is associated with schizophrenia in Koreans.

Intellect declines in healthy elderly subjects and cerebellum.

Scores of the performance scale of the Wechsler Adult Intelligence Scale (WAIS) declined linearly with age from the 6th decade, whereas those of the verbal scale did not. This decrease in performance intelligence was thought to be related to an age-related frontal atrophy. The relationship between scores of the WAIS and changes in regional cortical gray matter density were examined in healthy elderly subjects using voxel-based morphometry. Thirty healthy non-demented individuals >50 years of age were tested with the WAIS and scanned with brain magnetic resonance imaging (MRI). The right neocerebellum was significantly associated with scores of the performance intelligence scale while frontal lobes were not. The current study suggests that the cerebellum may play an important role in changes of intellectual capacity in old age.