Age-associated changes in immune cells have been linked to an increased risk for infection. However, a global and detailed characterization of the changes that human circulating immune cells undergo with age is lacking. Here, we combined scRNA-seq, mass cytometry and scATAC-seq to compare immune cell types in peripheral blood collected from young and old subjects and patients with COVID-19. We found that the immune cell landscape was reprogrammed with age and was characterized by T cell polarization from naive and memory cells to effector, cytotoxic, exhausted and regulatory cells, along with increased late natural killer cells, age-associated B cells, inflammatory monocytes and age-associated dendritic cells. In addition, the expression of genes, which were implicated in coronavirus susceptibility, was upregulated in a cell subtype-specific manner with age. Notably, COVID-19 promoted age-induced immune cell polarization and gene expression related to inflammation and cellular senescence. Therefore, these findings suggest that a dysregulated immune system and increased gene expression associated with SARS-CoV-2 susceptibility may at least partially account for COVID-19 vulnerability in the elderly.
Adult ; Aged ; Aged, 80 and over ; Aging ; genetics ; immunology ; Betacoronavirus ; CD4-Positive T-Lymphocytes ; metabolism ; Cell Lineage ; Chromatin Assembly and Disassembly ; Coronavirus Infections ; immunology ; Cytokine Release Syndrome ; etiology ; immunology ; Cytokines ; biosynthesis ; genetics ; Disease Susceptibility ; Flow Cytometry ; methods ; Gene Expression Profiling ; Gene Expression Regulation, Developmental ; Gene Rearrangement ; Humans ; Immune System ; cytology ; growth & development ; immunology ; Immunocompetence ; genetics ; Inflammation ; genetics ; immunology ; Mass Spectrometry ; methods ; Middle Aged ; Pandemics ; Pneumonia, Viral ; immunology ; Sequence Analysis, RNA ; Single-Cell Analysis ; Transcriptome ; Young Adult

Osteoarthritis (OA) is a degenerative articular disorder manifested by cartilage destruction, subchondral sclerosis, osteophytes, and synovitis, resulting in chronic joint pain and physical disability in the elderly. The purpose of this study was to investigate mitochondrial DNA copy number (mtDNA_CN) and inflammatory cytokines in primary knee OA patients and healthy volunteers. A total of 204 knee OA patients and 169 age-matched healthy volunteers were recruited. Their relative blood leukocyte mtDNA_CN was assessed by quantitative real-time polymerase chain reaction (qRT-PCR), and ten inflammatory cytokines in their plasma were detected by multiplex immunoassay. Blood leukocyte mtDNA_CN in the OA group was significantly lower than that in the control group. Leukocyte mtDNA_CN in the control group was negatively correlated with their age (r=-0.380, P<0.0001), whereas mtDNA_CN in the OA group was positively correlated with their age (r=0.198, P<0.001). Plasma interleukin-4 (IL-4) and IL-6 were significantly higher in the knee OA group than in the control group. The plasma IL-6 level was positively correlated with blood leukocyte mtDNA_CN in the OA group (r=0.547, P=0.0014). IL-5 showed as a major factor (coefficient 0.69) in the second dimension of principle components analysis (PCA)-transformed data and was significantly higher in the OA group (P<0.001) as well as negatively correlated with mtDNA_CN (r=-0.577, P<0.001). These findings suggest that elevation of plasma IL-4 and IL-6 and a relative reduction in mtDNA_CN might be effective biomarkers for knee OA. IL-5 is a plausible factor responsible for decreasing blood leukocyte mtDNA_CN in knee OA patients.
Age Factors ; Aged ; Aged, 80 and over ; Cytokines/blood* ; DNA, Mitochondrial/blood* ; Female ; Gene Dosage ; Humans ; Leukocytes/metabolism* ; Male ; Middle Aged ; Osteoarthritis, Knee/metabolism* ; Principal Component Analysis

Although atopic dermatitis (AD) is known to be a representative skin disorder, it also affects the systemic immune response. In a recent study, myoblasts were shown to be involved in the immune regulation, but the roles of muscle cells in AD are poorly understood. We aimed to identify the relationship between mitochondria and atopy by genome-wide analysis of skeletal muscles in mice. We induced AD-like symptoms using house dust mite (HDM) extract in NC/Nga mice. The transcriptional profiles of the untreated group and HDM-induced AD-like group were analyzed and compared using microarray, differentially expressed gene and functional pathway analyses, and protein interaction network construction. Our microarray analysis demonstrated that immune response-, calcium handling-, and mitochondrial metabolism-related genes were differentially expressed. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology pathway analyses, immune response pathways involved in cytokine interaction, nuclear factor-kappa B, and T-cell receptor signaling, calcium handling pathways, and mitochondria metabolism pathways involved in the citrate cycle were significantly upregulated. In protein interaction network analysis, chemokine family-, muscle contraction process-, and immune response-related genes were identified as hub genes with many interactions. In addition, mitochondrial pathways involved in calcium signaling, cardiac muscle contraction, tricarboxylic acid cycle, oxidation-reduction process, and calcium-mediated signaling were significantly stimulated in KEGG and Gene Ontology analyses. Our results provide a comprehensive understanding of the genome-wide transcriptional changes of HDM-induced AD-like symptoms and the indicated genes that could be used as AD clinical biomarkers.
Animals ; Biomarkers ; Calcium ; Calcium Signaling ; Citric Acid ; Citric Acid Cycle ; Cytokines ; Dermatitis, Atopic ; Gene Ontology ; Genome ; Metabolism ; Mice ; Microarray Analysis ; Mitochondria ; Muscle Cells ; Muscle Contraction ; Muscle, Skeletal ; Myoblasts ; Myocardium ; Oxidation-Reduction ; Protein Interaction Maps ; Pyroglyphidae ; Receptors, Antigen, T-Cell ; Skin

The activation mechanism of chimeric antigen receptor (CAR)-engineered T cells may differ substantially from T cells carrying native T cell receptor, but this difference remains poorly understood. We present the first comprehensive portrait of single-cell level transcriptional and cytokine signatures of anti-CD19/4-1BB/CD28/CD3ζ CAR-T cells upon antigen-specific stimulation. Both CD4 helper T (T) cells and CD8 cytotoxic CAR-T cells are equally effective in directly killing target tumor cells and their cytotoxic activity is associated with the elevation of a range of T1 and T2 signature cytokines, e.g., interferon γ, tumor necrotic factor α, interleukin 5 (IL5), and IL13, as confirmed by the expression of master transcription factor genes TBX21 and GATA3. However, rather than conforming to stringent T1 or T2 subtypes, single-cell analysis reveals that the predominant response is a highly mixed T1/T2 function in the same cell. The regulatory T cell activity, although observed in a small fraction of activated cells, emerges from this hybrid T1/T2 population. Granulocyte-macrophage colony stimulating factor (GM-CSF) is produced from the majority of cells regardless of the polarization states, further contrasting CAR-T to classic T cells. Surprisingly, the cytokine response is minimally associated with differentiation status, although all major differentiation subsets such as naïve, central memory, effector memory, and effector are detected. All these suggest that the activation of CAR-engineered T cells is a canonical process that leads to a highly mixed response combining both type 1 and type 2 cytokines together with GM-CSF, supporting the notion that polyfunctional CAR-T cells correlate with objective response of patients in clinical trials. This work provides new insights into the mechanism of CAR activation and implies the necessity for cellular function assays to characterize the quality of CAR-T infusion products and monitor therapeutic responses in patients.
Antigens ; metabolism ; CTLA-4 Antigen ; metabolism ; Cell Differentiation ; drug effects ; Cell Line ; Cytokines ; metabolism ; Cytotoxicity, Immunologic ; drug effects ; Granulocyte-Macrophage Colony-Stimulating Factor ; pharmacology ; Humans ; Lymphocyte Activation ; drug effects ; immunology ; Lymphocyte Subsets ; drug effects ; metabolism ; Phenotype ; Proteomics ; Receptors, Chimeric Antigen ; metabolism ; Single-Cell Analysis ; methods ; T-Lymphocytes, Regulatory ; drug effects ; metabolism ; Th1 Cells ; cytology ; drug effects ; Th2 Cells ; cytology ; drug effects ; Transcription, Genetic ; drug effects ; Up-Regulation ; drug effects

BACKGROUND: Asthma is a common cause of breathing difficulty in children and adults, and is characterized by chronic airway inflammation that is poorly controlled by available treatments. This results in severe disability and applies a huge burden to the public health system. Methane has been demonstrated to function as a therapeutic agent in many diseases. The aim of the present study was to explore the effect of methane-rich saline (MRS) on the pathophysiology of a mouse model of asthma and its underlying mechanism. METHODS: A murine model of ovalbumin (OVA)-induced allergic asthma was applied in this study. Mice were divided into three groups: a control group, an OVA group, and OVA-induced asthmatic mice treated with MRS as the third group. Lung resistance index (RI) and dynamic compliance (Cdyn) were measured to determine airway hyper-responsiveness (AHR). Haematoxylin and eosin (H&E) staining was performed and scored to show histopathological changes. Cell counts of bronchoalveolar lavage fluid (BALF) were recorded. Cytokines interleukin (IL)-4, IL-5, IL-13, tumor necrosis factor α (TNF-α), and C-X-C motif chemokine ligand 15 (CXCL15) from BALF and serum were measured by enzyme-linked immunosorbent assay (ELISA). The oxidative stress indexes, including malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), myeloperoxidase (MPO), and 8-hydroxydeoxyguanosine (8-OHdG), were determined using commercial kits. Apoptosis was evaluated by western blot, quantitative real-time polymerase chain reaction (qRT-PCR), and biochemical examination. RESULTS: MRS administration reversed the OVA-induced AHR, attenuated the pathological inflammatory infiltration, and decreased the cytokines IL-4, IL-5, IL-13, TNF-α, and CXCL15 in serum and BALF. Moreover, following MRS administration, the oxidative stress was alleviated as indicated by decreased MDA, MPO, and 8-OHdG, and elevated SOD and GSH. In addition, MRS exhibited an anti-apoptotic effect in this model, protecting epithelial cells from damage. CONCLUSIONS Methane improves pulmonary function and decreases infiltrative inflammatory cells in the allergic asthmatic mouse model. This may be associated with its anti-inflammatory, antioxidative, and anti-apoptotic properties.
Animals ; Apoptosis/drug effects* ; Asthma/metabolism* ; Bronchial Hyperreactivity/drug therapy* ; Cytokines/analysis* ; Female ; Inflammation/prevention & control* ; Methane/pharmacology* ; Mice ; Mice, Inbred BALB C ; Oxidative Stress/drug effects* ; Saline Solution

Dendrobii Caulis (DC), named 'Shihu' in Chinese, is a precious herb in traditional Chinese medicine. It is widely used to nourish stomach, enhance body fluid production, tonify "Yin" and reduce heat. More than thirty Dendrobium species are used as folk medicine. Some compounds from DC exhibit inhibitory effects on macrophage inflammation. In the present study, we compared the anti-inflammatory effects among eight Dendrobium species. The results provided evidences to support Dendrobium as folk medicine, which exerted its medicinal function partially by its inhibitory effects on inflammation. To investigate the anti-inflammatory effect of Dendrobium species, mouse macrophage cell line RAW264.7 was activated by lipopolysaccharide. The nitric oxide (NO) level was measured using Griess reagent while the pro-inflammatory cytokines were tested by ELISA. The protein expressions of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2) and mitogen-activated protein kinases (MAPKs) phosphorylation were evaluated by Western blotting analysis. Among the eight Dendrobium species, both water extracts of D. thyrsiflorum B.S.Williams (DTW) and D. chrysotoxum Lindl (DCHW) showed most significant inhibitory effects on NO production in a concentration-dependent manner. DTW also significantly reduced TNF-α, MCP-1, and IL-6 production. Further investigations showed that DTW suppressed iNOS and COX-2 expression as well as ERK and JNK phosphorylation, suggesting that the inhibitory effects of DTW on LPS-induced macrophage inflammation was through the suppression of MAPK pathways. In conclusion, D. thyrsiflorum B.S.Williams was demonstrated to have potential to be used as alternative or adjuvant therapy for inflammation.
Animals ; Anti-Inflammatory Agents ; pharmacology ; Cyclooxygenase 2 ; genetics ; Cytokines ; metabolism ; Dendrobium ; chemistry ; Gene Expression Regulation, Enzymologic ; drug effects ; Inflammation ; chemically induced ; drug therapy ; Lipopolysaccharides ; Macrophages ; drug effects ; enzymology ; Mice ; Mitogen-Activated Protein Kinases ; antagonists & inhibitors ; genetics ; metabolism ; Nitric Oxide ; analysis ; Nitric Oxide Synthase Type II ; genetics ; Phosphorylation ; drug effects ; Plant Extracts ; pharmacology ; RAW 264.7 Cells ; Signal Transduction ; drug effects

To explore the therapeutic effect of honokiol on particulate matter 2.5 (PM2.5)-induced lung injury in asthmatic mice and the possible mechanisms.
 Methods: A total of 32 BALB/C mice were randomly divided into four groups: a normal saline group, a model group, a PM2.5 group and a honokiol group (n=8 in each group). The asthma mouse model was established by ovalbumin treatment. The mice were treated with physiological saline, ovalbumin, PM2.5 and honokiol, respectively. Lung tissues and serum were collected. The pathological changes of lung tissues were evaluated. The levels of inflammatory cytokines in bronchoalveolar lavage fluid (BALF) and serum were measured and the expressions of Toll like receptor 4 (TLR4), nuclear factor kappa B (NF-κB), retinoid-related orphan receptor gamma-t (RORγt) and forkhead box protein 3 (Foxp3) in lung tissues were detected.
 Results: 1) The lung tissues of mice in the asthma group showed obvious pathological changes and inflammatory state, suggesting that the asthma model was established successfully. PM2.5 could aggravate the pathological condition of inflammatory injury in lung tissues in asthmatic mice. 2) Compared to the PM2.5 group, the pathological symptoms in the lung tissues were alleviated in the honokiol group and the percentage of inflammatory cells in BALF and the levels of inflammatory cytokines in BALF and serum were significantly reduced (all P<0.05). 3) Compared to the PM2.5 group, the expressions of TLR4, NF-κB (p-p65) and RORγt in lung tissues were significantly decreased, while the expression of Foxp3 was increased; the ratio of RORγt/Foxp3 was also decreased in the honokiol group (all P<0.05).
 Conclusion: Honokiol can resist lung injury induced by PM2.5 in asthmatic mice. These effects are through inhibiting TLR4-NF-κB pathway-mediated inflammatory response or regulating the balance of Th17/Treg cells.
Animals ; Asthma ; chemically induced ; complications ; Biphenyl Compounds ; pharmacology ; Bronchoalveolar Lavage Fluid ; chemistry ; Cytokines ; analysis ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Inflammation Mediators ; analysis ; Lignans ; pharmacology ; Lung ; metabolism ; pathology ; Lung Injury ; drug therapy ; etiology ; metabolism ; pathology ; Mice ; Mice, Inbred BALB C ; NF-kappa B ; metabolism ; Ovalbumin ; Particulate Matter ; toxicity ; Random Allocation ; Toll-Like Receptor 4 ; metabolism

To investigate the effect of bromodomain and extra-terminal (BET) protein inhibitor JQ1 on expression of autoimmune-related genes in CD4+T cells from patients with systemic lupus erythematosus (SLE).
 Methods: Peripheral CD4+T cells were isolated by positive selection with CD4 microbeads. The percentage of CD4+T cells were detected by flow cytometry. CD4+T cells were treated by JQ1 at 100 nm/L for 6, 24, 48 h. The expression of T cell-related genes was measured by quantitative real-time PCR (qPCR). The secretion levels of cytokines in culture supernatant were measured by ELISA at 48 h.
 Results: The percentage of CD4+T cells isolated by CD4 microbeads is 97.2%. Compared with the control group, the mRNA expression levels of IFNG, IL-17F, IL-21, CXCR5 and FOXP3 were down-regulated at 6, 24 and 48 h (P<0.05), and IL-17A mRNA level was decreased at 6 and 24 h (P<0.01); while IL-4 mRNA level was up-regulated at 24, 48 h (P<0.01), and TGF-β1 mRNA level was up-regulated at 6 and 48 h (P<0.05) in SLE CD4+T cells treated with JQ1. The secretion levels of IFN-γ and IL-21 in JQ1-treated group were decreased significantly (P<0.05), while the secretion levels of IL-4 and TGF-β were up-regulated compared with control group (P<0.05).
 Conclusion: JQ1 can reverse the immune dysregulation and improve the immunity homeostasis in CD4+T cells from patients with SLE.
Azepines ; pharmacology ; CD4 Lymphocyte Count ; CD4-Positive T-Lymphocytes ; cytology ; drug effects ; metabolism ; Cytokines ; analysis ; metabolism ; Flow Cytometry ; Humans ; Interferon-gamma ; metabolism ; Lupus Erythematosus, Systemic ; immunology ; metabolism ; Proteins ; antagonists & inhibitors ; RNA, Messenger ; metabolism ; Time Factors ; Transforming Growth Factor beta1 ; Triazoles ; pharmacology

Asthma is a chronic disease of airway inflammation due to excessive T helper cell type 2 (Th2) response. Present treatment based on inhalation of synthetic glucocorticoids can only control Th2-driven chronic eosinophilic inflammation, but cannot change the immune tolerance of the body to external allergens. Regulatory T cells (Tregs) are the main negative regulatory cells of the immune response. Tregs play a great role in regulating allergic, autoimmune, graft-versus-host responses, and other immune responses. In this review, we will discuss the classification and biological characteristics, the established immunomodulatory mechanisms, and the characteristics of induced differentiation of Tregs. We will also discuss the progress of Tregs in the field of asthma. We believe that further studies on the regulatory mechanisms of Tregs will provide better treatments and control strategies for asthma.
Antigens, CD/analysis* ; Apyrase/analysis* ; Asthma/immunology* ; Cell Differentiation ; Cytokines/metabolism* ; Humans ; Lymphocyte Transfusion ; T-Lymphocytes, Regulatory/immunology*

Immunoglobulin A (IgA) vasculitis is the most common leukocytoclastic small-vessel vasculitis in children and mainly involves the small vessels in the skin, joints, digestive tract, and kidneys. Its pathogenesis is still unclear. Currently, it is believed that environmental factors can cause autoimmune dysfunction and lead to the deposition of IgA-containing immune complexes on the wall of arterioles on the basis of genetic factors. This article reviews the research advances in the role of immune factors in the pathogenesis of IgA vasculitis.
Autoantibodies ; analysis ; Complement System Proteins ; physiology ; Cytokines ; physiology ; Glycosylation ; Humans ; Immunoglobulin A ; analysis ; Immunoglobulin E ; metabolism ; Vasculitis ; etiology ; immunology