Thioredoxin-interacting protein is essential for memory T cell formation via the regulation of the redox metabolism.

CD4+ memory T cells are central to long-lasting protective immunity and are involved in shaping the pathophysiology of chronic inflammation. While metabolic reprogramming is critical for the generation of memory T cells, the mechanisms controlling the redox metabolism in memory T cell formation remain unclear. We found that reactive oxygen species (ROS) metabolism changed dramatically in T helper-2 (Th2) cells during the contraction phase in the process of memory T cell formation. Thioredoxin-interacting protein (Txnip), a regulator of oxidoreductase, regulated apoptosis by scavenging ROS via the nuclear factor erythroid 2-related factor 2 (Nrf2)-biliverdin reductase B (Blvrb) pathway. Txnip regulated the pathology of chronic airway inflammation in the lung by controlling the generation of allergen-specific pathogenic memory Th2 cells in vivo. Thus, the Txnip-Nrf2-Blvrb axis directs ROS metabolic reprogramming in Th2 cells and is a potential therapeutic target for intractable chronic inflammatory diseases.

DIRECTEUR: transcriptome-based prediction of small molecules that replace transcription factors for direct cell conversion.

MOTIVATION: Direct reprogramming (DR) is a process that directly converts somatic cells to target cells. Although DR via small molecules is safer than using transcription factors (TFs) in terms of avoidance of tumorigenic risk, the determination of DR-inducing small molecules is challenging. RESULTS: Here we present a novel in silico method, DIRECTEUR, to predict small molecules that replace TFs for DR. We extracted DR-characteristic genes using transcriptome profiles of cells in which DR was induced by TFs, and performed a variant of simulated annealing to explore small molecule combinations with similar gene expression patterns with DR-inducing TFs. We applied DIRECTEUR to predicting combinations of small molecules that convert fibroblasts into neurons or cardiomyocytes, and were able to reproduce experimentally verified and functionally related molecules inducing the corresponding conversions. The proposed method is expected to be useful for practical applications in regenerative medicine. AVAILABILITY AND IMPLEMENTATION: The code and data are available at the following link: https://github.com/HamanoLaboratory/DIRECTEUR.git.

Higher Frequency of Premature Atrial Contractions Correlates With Atrial Fibrillation Detection after Cryptogenic Stroke.

BACKGROUND: Covert atrial fibrillation (AF) is a major cause of cryptogenic stroke. This study investigated whether a dose-dependent relationship exists between the frequency of premature atrial contractions (PACs) and AF detection in patients with cryptogenic stroke using an insertable cardiac monitor (ICM). METHODS: We enrolled consecutive patients with cryptogenic stroke who underwent ICM implantation between October 2016 and September 2020 at 8 stroke centers in Japan. Patients were divided into 3 groups according to the PAC count on 24-hour Holter ECG: ≤200 (group L), >200 to ≤500 (group M), and >500 (group H). We defined a high AF burden as above the median of the cumulative duration of AF episodes during the entire monitoring period. We evaluated the association of the frequency of PACs with AF detection using log-rank trend test and Cox proportional hazard model and with high AF burden using logistic regression model, adjusting for age, sex, CHADS2 score. RESULTS: Of 417 patients, we analyzed 381 patients with Holter ECG and ICM data. The median age was 70 (interquartile range, 59.5-76.5), 246 patients (65%) were males, and the median duration of ICM recording was 605 days (interquartile range, 397-827 days). The rate of new AF detected by ICM was higher in groups with more frequent PAC (15.5%/y in group L [n=277] versus 44.0%/y in group M [n=42] versus 71.4%/y in group H [n=62]; log-rank trend P<0.01). Compared with group L, the adjusted hazard ratios for AF detection in groups M and H were 2.11 (95% CI, 1.24-3.58) and 3.23 (95% CI, 2.07-5.04), respectively, and the adjusted odds ratio for high AF burden in groups M and H were 2.57 (95% CI, 1.14-5.74) and 4.25 (2.14-8.47), respectively. CONCLUSIONS: The frequency of PACs was dose-dependently associated with AF detection in patients with cryptogenic stroke.

Immature stroma and high infiltration of CD15+ cells are predictive markers of poor prognosis in different subsets of patients with pancreatic cancer.

Preoperative treatment is commonly carried out for borderline resectable pancreatic ductal adenocarcinoma (PDAC). However, the relationship between the combination of immune cells in the tumor microenvironment and their intratumoral heterogeneity along with their association with histological findings remains unclear, especially in patients receiving preoperative chemotherapy. We aimed to explore the therapeutic strategies for patients with PDAC with poor prognosis after receiving chemotherapy based on histological and immunological microenvironmental classifications. We investigated the correlation between the prognosis and histological immune microenvironmental factors of patients who initially underwent surgery (n = 100) and were receiving gemcitabine plus nab-paclitaxel (GEM + nabPTX) as preoperative chemotherapy (n = 103). Immune profiles were generated based on immune cell infiltration into the tumor, and their correlation with patient outcomes and histological features was analyzed. Tumor-infiltrating neutrophils (TINs) were identified as independent poor prognostic factors using multivariate analysis in both surgery-first and preoperative chemotherapy groups. The patients were further classified into four groups based on immune cell infiltration into the tumor. Patients with high CD15 infiltration into the tumor and immature stroma at the cancer margins showed the worst prognosis in the preoperative chemotherapy group. The analysis of mRNA expression and immunohistochemical features revealed that CXCR2, the receptor for CXCL8, was correlated with disease-free and overall survival. We inferred that patients with immature stroma at the margins and high infiltration of CD15+ neutrophils within the tumor showed the worst prognosis and they could particularly benefit from treatment with inhibitors targeting CXCR2 or CXCL8.

Adjunctive brexpiprazole 1 mg and 2 mg daily for Japanese patients with major depressive disorder following inadequate response to antidepressants: a phase 2/3, randomized, double-blind (BLESS) study.

AIMS: Inadequate antidepressant response interrupts effective treatment of major depressive disorder (MDD). The BLESS study evaluates the dosage, efficacy, and safety of brexpiprazole adjunctive therapy in Japanese patients with inadequate antidepressant therapy (ADT) response. METHODS: This placebo-controlled, randomized, multicenter, parallel-group phase 2/3 study randomized Japanese MDD patients (Hamilton Rating Scale for Depression 17-item total score ≥ 14; historical inadequate response to 1-3 ADTs) with inadequate response to 8-week single-blind, prospective SSRI/SNRI treatment to 6-week adjunctive treatment with brexpiprazole 1 mg, 2 mg, or placebo. The primary endpoint was change in Montgomery-Åsberg Depression Rating Scale (MADRS) total score from baseline. Secondary endpoints included MADRS response, remission rate, and Clinical Global Impression-Improvement score. Safety was comprehensively evaluated, especially regarding antipsychotic adverse events (AEs). RESULTS: Of 1194 screened patients, 740 were randomized and 736 (1 mg, n = 248; 2 mg, n = 245; placebo, n = 243) had ≥1 baseline/post-baseline MADRS total score. The LSM (SE) change from baseline in MADRS total score at Week 6 by MMRM analysis was -8.5 (0.47) with brexpiprazole 1 mg, -8.2 (0.47) with brexpiprazole 2 mg, and -6.7 (0.47) with placebo (placebo-adjusted LSM difference [95% CI]: 1 mg, -1.7 [-3.0, -0.4]; P = 0.0089; 2 mg, -1.4 [-2.7, -0.1]; P = 0.0312). Secondary efficacy results supported the primary endpoint. Brexpiprazole was generally well tolerated. CONCLUSION: Brexpiprazole 1 mg daily was an appropriate starting dose and both 1 mg and 2 mg daily were effective and well tolerated as adjunctive therapy for Japanese MDD patients not adequately responsive to ADT.

Clinicopathologic Features and Genetic Alterations in Mixed-Type Ampullary Carcinoma.

Mixed-type ampullary carcinoma is a subtype that combines intestinal-type (I-type) and pancreatobiliary-type (PB-type) lesions, but few studies have examined its clinicopathologic features and genetic alterations. The differences in genetic alterations between mixed type and other subtypes, as well as the genetic differences between I-type and PB-type lesions in the mixed type, remain unclear. In this study, we compared the clinicopathologic features and prognosis of 110 ampullary carcinomas classified by hematoxylin and eosin and immunohistochemical staining as follows: 63 PB-type, 35 I-type, and 12 mixed-type carcinomas. A comparative analysis of genetic mutations by targeted sequencing of 24 genes was also performed in 3 I-type cases, 9 PB-type cases, and I and PB-type lesions of 6 mixed-type cases. The mixed subtype had a poorer prognosis than the other subtypes, and there was also a similar tendency in the adjuvant group (n = 22). A total of 49 genetic mutations were detected in all 18 lesions for which genetic alteration was analyzed. No genetic mutations specific to the mixed type were found, and it was not possible to determine genetically whether the mixed type had originally been I or PB type. However, 5 of 6 cases had mutations common to both I and PB-type lesions, and additional mutations were found only in either I or PB-type lesions. In support of this, the mixed type more frequently exhibited genetic heterogeneity intratumorally than the other subtypes. Mixed-type tumors are histologically, immunohistochemically, and genetically heterogeneous, and this heterogeneity is associated with poor prognosis and may affect treatment resistance.

Pharmaceutical company payments to authors of the Japanese Clinical Practice Guidelines for Hepatitis C treatment.

BACKGROUND & AIMS: Promotional activities of pharmaceutical companies (Pharma) relating to newly marketed direct-acting antivirals (DAAs) may have targeted the authors of the Japanese Clinical Practice Guidelines (CPGs) for Hepatitis C. This study aimed to assess payments made by Pharma to the CPG authors and the financial conflicts of interest (FCOIs) reported by those authors. METHODS: We analyzed payments reported by Pharma to the CPG authors as well as the COI as published by the JSH, using publicly available data for 2016 and 2017. RESULTS: A total of 35 of 78 Pharma-reported payments of $613,973 in 2016, while 40 of 73 Pharma declared payments of $524,674 in 2017, with six companies failing to report. Payments by Pharma manufacturing DAAs accounted for 53.7% of the total (55.7% and 51.6% in 2016 and 2017 respectively). All 17 authors received payments from Pharma which totalled $1,138,647. The mean and median payments per author were $66,979 (standard deviation (SD): $64,875) and $46,033 (interquartile range [IQR]: $29,796 - $34,428) for 2016 and 2017 combined. CONCLUSIONS: Financial relationship between Pharma and the Hepatitis C CPG authors, which was unclear owing to the guideline regulation, was clarified. The authors had the strongest ties to the Pharma which manufactures DAAs in 2016 and 2017.

Accuracy of post-publication Financial Conflict of Interest corrections in medical research: A secondary analysis of pharmaceutical company payments to the authors of the CREATE-X trial report in the New England Journal of Medicine.

In June 2017, Japanese and Korean authors published the results of the CREATE-X trial in the New England Journal of Medicine (NEJM). After we identified their inadequate disclosures of Financial Conflict of Interests (FCOIs), the authors made a post-publication correction of their FCOIs. The purpose of this study is to evaluate the accuracy of the post-publication corrections by the Japanese authors of the CREATE-X trial. All the Japanese authors of the CREATE-X trial were included in the study. We determined the payments received by these authors in 2016 using publicly available data published by 78 pharmaceutical companies based on the stipulated Japanese transparency guidelines. We retrieved the original and revised versions of the FCOI disclosures as published on the NEJM website, and compared the payments reported by the pharmaceutical companies and the original and revised FCOI disclosures of the authors. Of the 12 authors, nine received payments made by the drug manufacturer involved in the CREATE-X trial. Of these nine, only three (33.3%) originally disclosed their relationships, and another three (33.3%) later disclosed such relationships in the post-publication corrections. Similarly, of the 11 receiving at least one payment from other manufacturers of breast cancer products, none correctly disclosed the payments in the original or the revised disclosure. In the CREATE-X trial, FCOIs with pharmaceutical companies were not properly disclosed by 11 of the 12 Japanese authors, even after the post-publication corrections, which highlights the need to pay more attention to the accuracy of FCOI disclosures in academic publications.

Usefulness of the whole-body counter for infants and small children (BABYSCAN) as a risk communication tool after the Fukushima Daiichi nuclear power plant incident.

Responding to the radiation-related concerns of parents/guardians with infants/small children is an important public health issue for regional recovery after radioactive contamination. This study summarizes the results of a systematic internal contamination screening of infants/small children, aged 0-6 years, using BABYSCAN and individual counselling sessions with physicians about radiation concerns from 2014 to 2018 in Minamisoma City. Of 3,114 participants, no one was found to have internal contamination with radioactive caesium with a detection limit of 50 Bq/body. The questionnaire survey showed a decreasing trend of concerns about food contamination and playing outside as possible causes of internal contamination over time. Because people's concerns were diverse in counselling sessions, individual responses are required. This study showed that examinations using BABYSCAN provide an opportunity for direct dialogue between the parents/guardians of infants/small children and experts. This can be considered a model case for risk communication conducted by the local government after a radioactive contamination incident.

NOX1/NADPH Oxidase Expressed in Colonic Macrophages Contributes to the Pathogenesis of Colonic Inflammation in Trinitrobenzene Sulfonic Acid-Induced Murine Colitis.

NOX1/NADPH oxidase, a nonphagocytic isoform of reactive oxygen species-producing enzymes, is highly expressed in the colon, but the physiologic and pathophysiologic roles of this isoform are not fully understood. The present study investigated the role of NOX1 in the development of colonic inflammation in a trinitrobenzene sulfonic acid (TNBS)-induced murine colitis model. Intrarectal injection of TNBS caused severe colitis accompanied by body weight loss, diarrhea, and increased myeloperoxidase (MPO) activity in wild-type (WT) mice. In contrast, the severity of colitis was significantly attenuated in NOX1-deficient (NOX1KO) mice (the inhibitions of macroscopic damage score, body weight loss, diarrhea score, and MPO activity were 73.1%, 36.8%, 83.3%, and 98.4%, respectively). TNBS-induced upregulation of inflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-1ß), chemokines (CXCL1 and CXLC2), and inducible nitric oxide synthase (iNOS) was also significantly less in NOX1KO than in WT mice (the inhibitions were 100.8%, 89.0%, 63.5%, 96.7%, and 97.1%, respectively). Expression of NOX1 mRNA was detected not only in the lamina propria but also in peritoneal macrophages isolated from WT mice. Increased expression of TNF-α, IL-1ß, and iNOS in peritoneal macrophages exposed to lipopolysaccharide was significantly attenuated in macrophages isolated from NOX1KO mice (68.1%, 67.0%, and 79.3% inhibition, respectively). These findings suggest that NOX1/NADPH oxidase plays an important role in the pathogenesis of TNBS-induced colonic inflammation via upregulation of inflammatory cytokines, chemokines, and iNOS. NOX1 in colonic macrophages may become a potential target in pharmacologic intervention for inflammatory bowel disease.

Simple and direct assembly of kymographs from movies using KYMOMAKER.

In tracking analysis, the movement of cargos by motor proteins in axons is often represented by a time-space plot termed a 'kymograph'. Manual creation of kymographs is time-consuming and complicated for cell biologists. Therefore, we developed KYMOMAKER, a simple system that automatically creates a kymograph from a movie without generating multiple time-dissected movie stacks. In addition, KYMOMAKER can automatically extract faint vesicle traces, and can thereby effectively analyze cargos expressed at low levels in axons. A filter can be applied to remove traces of non-physiological movements and to extract meaningful traces of anterograde or retrograde cargo transport. For example, only cargos that move at a speed of >0.4 µm/second for a distance of >1 µm can be included. Another function of KYMOMAKER is to create a color kymograph in which the color of the trace varies according to the position of the fluorescent particle in the axis perpendicular to the long axis of the axon. Such positional information is completely lost in conventional kymographs. KYMOMAKER is an open access program that can be easily used to analyze vesicle transport in axons by cell biologists who do not have specific knowledge of bioimage informatics.

Whole-body counter surveys of over 2700 babies and small children in and around Fukushima Prefecture 33 to 49 months after the Fukushima Daiichi NPP accident.

BABYSCAN, a whole-body counter (WBC) for small children was developed in 2013, and units have been installed at three hospitals in Fukushima Prefecture. Between December, 2013 and March, 2015, 2707 children between the ages of 0 and 11 have been scanned, and none had detectable levels of radioactive cesium. The minimum detectable activities (MDAs) for (137)Cs were ≤ 3.5 Bq kg(-1) for ages 0-1, decreasing to ≤ 2 Bq kg(-1) for ages 10-11. Including the (134)Cs contribution, these translate to a maximum committed effective dose of ∼ 16 µSv y(-1) even for newborn babies, and therefore the internal exposure risks can be considered negligibly small.Analysis of the questionnaire filled out by the parents of the scanned children regarding their families' food and water consumption revealed that the majority of children residing in the town of Miharu regularly consume local or home-grown rice and vegetables, while in Minamisoma, a majority avoid tap water and produce from Fukushima. The data show, however, no correlation between consumption of locally produced food and water and the children's body burdens.

Pentraxin 3 is associated with disease activity but not atherosclerosis in patients with systemic lupus erythematosus.

OBJECTIVES: Pentraxin 3 (PTX3) plays an important role in inflammation, immunity, and atherosclerosis. Plasma PTX3 level has drawn attention as a marker that responds to local inflammation. Systemic lupus erythematosus (SLE), a chronic inflammatory disorder which can affect multiple organs, develops atherosclerosis prematurely. We examined the hypotheses that the concentration of plasma PTX3 increases in patients with SLE and that PTX3 is associated with the disease activity and premature atherosclerosis. METHODS: Plasma PTX3 concentrations were measured in 65 patients with SLE and 53 control subjects. The patients were also evaluated with respect to their clinical characteristics, disease activity indices, and corticosteroid therapy. We performed carotid ultrasonography to measure subclinical atherosclerosis in patients with SLE. RESULTS: Plasma PTX3 concentration of the SLE patients was significantly higher than that of the healthy controls (median 3.9 vs. 2.0 ng/mL, p < 0.001). In patients with SLE, PTX3 concentrations were correlated with SLEDAI (p = 0.011), BILAG index (p < 0.001), C-reactive protein (p < 0.001), anemia (p = 0.020), hypoalbuminemia (p = 0.022), and daily dose of prednisolone (p = 0.008) after adjustment for age and sex. PTX3 was not associated with disease duration, anti-ds DNA antibody, CH50, or carotid atherosclerosis. CONCLUSIONS: Patients with SLE have increased concentrations of PTX3 compared with control subjects. PTX3 was significantly associated with disease activity but not with carotid atherosclerosis.

Association between the controlling nutritional status score and outcomes in ischemic stroke patients with active cancer.

BACKGROUND: The effect of nutritional status on survival in ischemic stroke patients with active cancer remains unclear. METHODS: This study retrospectively evaluated ischemic stroke patients with active cancer admitted to a university hospital in Japan between 2006 and 2016. Patients were followed for 2 years after stroke. The controlling nutritional status (CONUT) score was used to classify undernutrition degree into 4 groups: normal, light, moderate, and severe. Survival rates were compared using the Kaplan-Meier method. Hazard ratio (HR) and 95 % confidence intervals (CIs) for mortality were calculated using Cox regression models. RESULTS: A total of 158 patients (31 % women; median age: 71 years) were analyzed. Of these, 47 % had distant metastasis. The median (interquartile range) National Institute of Health Stroke Scale and CONUT scores were 4 (1-10) and 5 (3-7), respectively. Kaplan-Meier curve indicated that patients with poorer nutritional status had worse outcomes (overall log-rank test, p < 0.001). The univariable Cox regression analysis showed that the HR (95 % CI) for the light, moderate, and severe groups were 1.14 (0.45-2.86), 3.01 (1.27-7.12), and 2.94 (1.10-7.84), respectively. This statistical significance did not persist after adjustment for potential confounders (HR [95 % CI] for the light, moderate, and severe groups were 0.95 [0.36-2.49], 1.56 [0.57-4.28], and 1.34 [0.37-4.92], respectively). Past stroke, distant metastasis, and plasma D-dimer levels on admission were independent predictors of prognosis. CONCLUSIONS: This single-center, retrospective study suggests that nutritional status serves as a prognostic indicator for ischemic stroke patients with active cancer. However, the effect is not statistically independent.

A case of Adult-onset Acute Flaccid Myelitis Accompanied by Rhombencephalitis which First Presented with Prominent Psychiatric Symptoms and Dysautonomia Mimicking Anti-N-methyl-d-aspartate Receptor Encephalitis.

A 44-year-old woman with a subacute onset of an altered mental status, urinary retention, and fluctuating blood pressure was initially diagnosed with anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis, meeting the criteria of Graus et al. Cardiac arrest occurred, which required pacemaker placement. She subsequently showed profound flaccid limb paralysis, with magnetic resonance imaging demonstrating focal necrotic lesions localized in the anterior horn of the longitudinal segments of the spinal cord and in the pontine tegmentum. Enteroviruses or autoimmune encephalitis-associated autoantibodies were not detected. We herein report a case of acute flaccid myelitis with profound psychiatric symptoms and dysautonomia, resembling NMDAR encephalitis.

Serum osteoprotegerin concentration is associated with carotid atherosclerotic plaque in patients with rheumatoid arthritis.

OBJECTIVE: Osteoprotegerin (OPG), a regulator of bone resorption, is involved in the pathogenesis of rheumatoid arthritis (RA) and atherosclerosis. OPG is elevated in patients with coronary artery disease, and high OPG levels are associated with cardiac disease severity and mortality in the general population. The purpose of this study was to investigate the relationship of serum OPG levels, traditional coronary risk factors, and RA-related factors to carotid atherosclerosis in RA patients. METHODS: Ninety-one RA patients were studied (85 % women, age 60 ± 10 years). Serum OPG levels were measured by an enzyme-linked immunosorbent assay. The prevalence of carotid plaque was assessed by ultrasonographic imaging in all patients. The relationship between various clinical characteristics, OPG, and carotid plaque was examined. RESULTS: Serum OPG levels were significantly higher in patients with carotid plaque than in those without plaque (median level 1,397 vs. 887 pg/mL, respectively; P = 0.006). There were no significant differences between RA patients with and without carotid plaque with respect to sex, duration of RA, blood pressure, body mass index, smoking, low-density lipoprotein cholesterol, Disease Activity Score-28, van der Heijde-modified Sharp score, and prednisolone dose. After adjusting for age, sex, and C-reactive protein, elevated levels of OPG were still associated with a higher prevalence of carotid plaque in patients with RA (P = 0.038). CONCLUSION: RA patients suffer from accelerated atherosclerosis and also have increased levels of OPG. The serum OPG level is independently associated with carotid plaque.

Lentinula Edodes Mycelia extract regulates the function of antigen-presenting cells to activate immune cells and prevent tumor-induced deterioration of immune function.

Immune cell activation is essential for cancer rejection; however, the tumor microenvironment leads to deterioration of immune function, which enables cancer cells to survive and proliferate. We previously reported that oral ingestion of Lentinula Edodes Mycelia (L.E.M.) extract enhances the tumor antigen-specific T-cell response and exerts an antitumor effect in a tumor-bearing mouse model. In this study, we focused on antigen-presenting cells (APCs) located upstream of the immune system, induced a T-cell response, then examined the impact of L.E.M. extract on the APCs. L.E.M. extract enhanced the expression of MHC-I, MHC-II, CD86, CD80, and CD40 in bone marrow-derived dendritic cells (DCs) and strongly induced the production of IL-12. L.E.M.-stimulated DCs enhanced IFN-γ production from CD8+ T cells and induced their differentiation into effector cells. Furthermore, L.E.M. extract promoted IL-12 production and suppressed the production of IL-10 and TGF-ß by transforming bone marrow-derived macrophages into M1-like macrophages. Furthermore, in a B16F10 melanoma inoculation model, DCs in the spleen were decreased and their activation was suppressed by the presence of cancer; however, ingestion of L.E.M. extract prevented this functional deterioration of DCs. In the spleen of cancer-bearing mice, the number of CD11b- F4/80+ macrophages in a hypoactivated state was also increased, whereas L.E.M. extract suppressed the increase of such macrophages. These findings suggest that L.E.M. extract may exhibit an antitumor immune response by regulating the function of APCs to induce cytotoxic T lymphocytes, as well as by suppressing the decline in antigen-presenting cell activity caused by the presence of cancer.

Single-cell RNA-seq analysis identifies distinct myeloid cells in a case with encephalitis temporally associated with COVID-19 vaccination.

Recently accumulating evidence has highlighted the rare occurrence of COVID-19 vaccination-induced inflammation in the central nervous system. However, the precise information on immune dysregulation related to the COVID-19 vaccination-associated autoimmunity remains elusive. Here we report a case of encephalitis temporally associated with COVID-19 vaccination, where single-cell RNA sequencing (scRNA-seq) analysis was applied to elucidate the distinct immune signature in the peripheral immune system. Peripheral blood mononuclear cells (PBMCs) were analyzed using scRNA-seq to clarify the cellular components of the patients in the acute and remission phases of the disease. The data obtained were compared to those acquired from a healthy cohort. The scRNA-seq analysis identified a distinct myeloid cell population in PBMCs during the acute phase of encephalitis. This specific myeloid population was detected neither in the remission phase of the disease nor in the healthy cohort. Our findings illustrate induction of a unique myeloid subset in encephalitis temporally associated with COVID-19 vaccination. Further research into the dysregulated immune signature of COVID-19 vaccination-associated autoimmunity including the cerebrospinal fluid (CSF) cells of central nervous system (CNS) is warranted to clarify the pathogenic role of the myeloid subset observed in our study.