Animals ; Asthma/pathology* ; CD4-Positive T-Lymphocytes/immunology* ; China/epidemiology* ; Disease Models, Animal ; Immunoglobulin E/blood* ; Incidence ; Lung/pathology* ; Mice ; Pollen/chemistry* ; Populus/adverse effects* ; Prevalence

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

The 2019 novel coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has occurred in China and around the world. SARS-CoV-2-infected patients with severe pneumonia rapidly develop acute respiratory distress syndrome (ARDS) and die of multiple organ failure. Despite advances in supportive care approaches, ARDS is still associated with high mortality and morbidity. Mesenchymal stem cell (MSC)-based therapy may be an potential alternative strategy for treating ARDS by targeting the various pathophysiological events of ARDS. By releasing a variety of paracrine factors and extracellular vesicles, MSC can exert anti-inflammatory, anti-apoptotic, anti-microbial, and pro-angiogenic effects, promote bacterial and alveolar fluid clearance, disrupt the pulmonary endothelial and epithelial cell damage, eventually avoiding the lung and distal organ injuries to rescue patients with ARDS. An increasing number of experimental animal studies and early clinical studies verify the safety and efficacy of MSC therapy in ARDS. Since low cell engraftment and survival in lung limit MSC therapeutic potentials, several strategies have been developed to enhance their engraftment in the lung and their intrinsic, therapeutic properties. Here, we provide a comprehensive review of the mechanisms and optimization of MSC therapy in ARDS and highlighted the potentials and possible barriers of MSC therapy for COVID-19 patients with ARDS.
Adoptive Transfer ; Alveolar Epithelial Cells ; pathology ; Animals ; Apoptosis ; Betacoronavirus ; Body Fluids ; metabolism ; CD4-Positive T-Lymphocytes ; immunology ; Clinical Trials as Topic ; Coinfection ; prevention & control ; therapy ; Coronavirus Infections ; complications ; immunology ; Disease Models, Animal ; Endothelial Cells ; pathology ; Extracorporeal Membrane Oxygenation ; Genetic Therapy ; methods ; Genetic Vectors ; administration & dosage ; therapeutic use ; Humans ; Immunity, Innate ; Inflammation Mediators ; metabolism ; Lung ; pathology ; physiopathology ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stem Cells ; physiology ; Multiple Organ Failure ; etiology ; prevention & control ; Pandemics ; Pneumonia, Viral ; complications ; immunology ; Respiratory Distress Syndrome, Adult ; immunology ; pathology ; therapy ; Translational Medical Research

Biomarkers ; metabolism ; CD4-Positive T-Lymphocytes ; immunology ; metabolism ; Cytomegalovirus Retinitis ; immunology ; Female ; Humans ; Male ; Polymerase Chain Reaction ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; immunology ; metabolism ; virology

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

OBJECTIVE: To study the effect of electro- acupuncture at Zusanli acupoint in regulating perioperative cell immune functions in rats. METHODS: Forty-two SD rats were divided into blank control group (=6), model group (=18), and electroacupuncture group (=18). The rats in the latter two groups underwent thigh incision and femoral dissection under anesthesia; the rats in electro-acupuncture group received electro-acupuncture at bilateral Zusanli acupoint for 15 min before anesthesia and 1 h after the surgery. The rats in the model group and electro-acupuncture group were sacrificed at 6 h, 24 h, and 72 h after the operation and blood samples were taken from the ventricle for analyzing CD3, CD4, and CD8 T cell subpopulations and calculation of CD4/CD8 using flow cytometry. ELISA was used to detect the levels of interleukin-1 (IL-1) and IL-6. RESULTS: The CD3 T cell subpopulation was significantly lower in the model group and electro-acupuncture group than in the blank group at 6 h and 24 h after the operation. At 72 h after the operation, CD3 subpopulation levels still remained low in the model group, but recovered the control level in electro-acupuncture group. At each time point of measurement, CD3 level was significantly lower in the model group than in the electro-acupuncture group. CD4 level in the model group was significantly lowered at 6 h and 24 h after the operation, and recovered the control level at 72 h. In the electro-acupuncture group, CD4 level was significantly lowered at 6 h after the operation, but recovered the control level at 24 h. At 24 h and 72 h, the levels of CD4 were significantly lower in the model group than in the electro-acupuncture group. CD8 level underwent no significant changes after the operation in either the model group or electro-acupuncture group. CD4/CD8 was significantly lowered at 24 h and 72 h after the operation in the model group but showed no significant variation in the electro-acupuncture group. Compared with that in the control group, IL-1 level was significantly lowered in both the model group and electroacupuncture group at 6 h, 24 h, and 72 h after the operation, and was significantly lower in the model group than in the electroacupuncture group at these time points. IL-6 level increased significantly in the model group and the electro- acupuncture group at 6 h and 24 h. at 72 h, IL-6 level was obviously lowered in the electro-acupuncture group but remained elevated in the model group. CONCLUSIONS Electro-acupuncture alleviates postoperative immune suppression and promotes recovery of the immune function in rats, suggesting a protective effect of electro-acupuncture at Zusanli acupoint on cellular immune function after surgery.
Acupuncture Points ; Animals ; CD4-Positive T-Lymphocytes ; cytology ; immunology ; CD8-Positive T-Lymphocytes ; cytology ; immunology ; Electroacupuncture ; methods ; Femur ; surgery ; Flow Cytometry ; Humans ; Immunity, Cellular ; Perioperative Period ; Rats ; Rats, Sprague-Dawley ; T-Lymphocyte Subsets ; cytology ; immunology

OBJECTIVE: To identify differentially expressed genes in peripheral blood mononuclear cells between patients with continuous mild-to-moderate asthma and healthy controls using mRNA microarray in order to explore the underlying signaling pathways and clarify the roles of CD4+ T cells in the pathogenesis of asthma. METHODS: Global transcriptomic profiles of the CD4+ T cells were defined by using Agilent Sure Print G3 Human GE 8×60K microarray. Enrichment pathways were analyzed with Ingenuity Pathway Analysis (IPA) software. RESULTS: Compared with controls, 805 genes were up-regulated, 192 were down-regulated in asthma patients. Among these, the expression of 38 annotated genes have varied by 4 times or more. Expression of CD300A was inversely proportional to the absolute value of eosinophils (r=-0.89, P=0.02) as well as the proportion of eosinophils (r=-0.94, P=0.004), while CSF1R was inversely proportional to PD20 (r=-0.83, P=0.04) and AQLQ (r=-0.88, P=0.02) by correlation analysis. CONCLUSION Numerous pathophysiological pathways may be involved in the pathogenesis of asthma. Above findings have provided a basis for the delineation the pathogenesis of asthma.
Antigens, CD ; genetics ; Asthma ; immunology ; CD4-Positive T-Lymphocytes ; cytology ; Case-Control Studies ; Eosinophils ; Gene Expression Profiling ; Humans ; Leukocytes, Mononuclear ; Oligonucleotide Array Sequence Analysis ; Receptors, Granulocyte-Macrophage Colony-Stimulating Factor ; genetics ; Receptors, Immunologic ; genetics ; Transcriptome

Systemic lupus erythematosus (SLE) is a highly heterogeneous autoimmune disease, characterized by production of pathogenic autoantibodies and wide involvement of multiple systems. Damageofimmune tolerance and imbalance of immune homeostasis lead to the production of autoantibodies and the injuries of multiple organs and systems. In recent years, plenty of studies have identified that immunometabolism affects survival status of certain cells, also cell activation, differentiation and effector functions. Conversely, immune cells with different functions or differentiational status upregulate specific metabolic pathways to maintain their identities. In response to outer stimulations, naive immune cells differentiate into activated cells, accompanied with a series of immunometabolism changes. Therefore, abnormal immunometabolism can induce global imbalance of immune homeostasis, which further results in the initiation and development of autoimmune diseases, including SLE. Multiple abnormalities of immunometabolism have been found in patients with SLE or mouse models of lupus. Immune cells involved in the development of SLE, such as T cells, B cells, dendritic cells and macrophages present various metabolic abnormalities and pathological phenotypes. Among these cells, CD4+ T cells play predominant roles in the pathogenesis of SLE. Lots of studies demonstrated that CD4+ T cells and their subsets were in abnormal immunometabolic status,which further resulted in the development of SLE. In CD4+ T cells from patients with SLE or mouse models of lupus, both levels of glycolysis and oxidative phosphorylation are significantly higher compared with healthy controls. However,mitochondrial abnormalities, decreased ATP production and increased level of oxidative stress also have been found in these cells, which play important roles in the production of reactive oxygen intermediates and autoantibodies. Aggregated lipids rafts and increased synthesis of glycosphingolipid and cholesterol also have been observed in the CD4+ T cells from patients with SLE, leading to the abnormally elevated TCR signaling. Moreover, mechanistic target of rapamycin (mTOR) signaling is activated in the CD4+ T cells from both patients with SLE or mouse models of lupus and participate in the metabolic abnormalities of pathological CD4+ T cells. Progressive understanding of immunometabolism give us new insights of the pathogenesis of SLE and provide us with more therapeutic targets in the treatment of SLE.
Animals ; Autoantibodies ; CD4-Positive T-Lymphocytes ; Cell Differentiation ; Humans ; Lupus Erythematosus, Systemic/immunology* ; Mice ; Signal Transduction

Though the cases of HIV patients with paraquat (PQ) poisoning are rare, we still found the common features. These recovered HIV patients tended to result in much less lung injury, and had low CD4⁺ T lymphocyte levels due to HIV infection, which meant they were under the immunosuppressive condition during treatment. This may be conducive to relieve the acute inflammation and lung fibrosis induced by PQ. Thus, we consider the immunosuppressive therapy for PQ poisoning to be appropriate. However, the drugs used currently may be not optimal for toxic patient. As next step, we will add the CD4⁺ T lymphocyte-targeted immunosuppressive drug to treat PQ poisoning patients.
CD4-Positive T-Lymphocytes/immunology* ; HIV Infections/immunology* ; Humans ; Immunosuppressive Agents/therapeutic use* ; Paraquat/poisoning*

Metastasis is the leading cause of death in breast cancer patients. However, the mechanisms underlying metastasis are not well understood and there is no effective treatment in the clinic. Here, we demonstrate that in MMTV-PyMT, a highly malignant spontaneous breast tumor model, IL-25 (also called IL-17E) was expressed by tumor-infiltrating CD4 T cells and macrophages. An IL-25 neutralization antibody, while not affecting primary tumor growth, substantially reduced lung metastasis. Inhibition of IL-25 resulted in decreased type 2 T cells and macrophages in the primary tumor microenvironments, both reported to enhance breast tumor invasion and subsequent metastasis to the lung. Taken together, our data suggest IL-25 blockade as a novel treatment for metastatic breast tumor.
Animals ; Antibodies, Neoplasm ; pharmacology ; Antibodies, Neutralizing ; pharmacology ; Breast Neoplasms ; drug therapy ; genetics ; immunology ; CD4-Positive T-Lymphocytes ; immunology ; pathology ; Female ; Humans ; Interleukin-17 ; antagonists & inhibitors ; genetics ; immunology ; Interleukins ; antagonists & inhibitors ; genetics ; immunology ; Macrophages ; immunology ; pathology ; Mammary Neoplasms, Animal ; drug therapy ; genetics ; immunology ; Mice ; Neoplasm Metastasis ; Tumor Microenvironment ; drug effects ; genetics ; immunology