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

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

OBJECTIVETo investigate the effect of tumor necrosis factor-α-induced protein 8 like-2 (TIPE2) on apoptosis of CD4T lymphocytes in a murine model of severe burn injury.

METHODSA total of 140 male mice were randomly allocated into 6 groups. Small RNA interference technique was used to construct a siTIPE2-overexpressing lentivirus, and severe burn injury models were established in the mice. CD4T cells were purified from spleen of the mice, and the expressions of TIPE2, Smad2/Smad3, P-Smad2/P-Smad3 and Bcl-2/Bimprotein in CD4Tregs were detected. The changes in mitochondrial membrane potential and cytochrome C in CD4T cells were detected, and the activities of caspase-3, caspase-8, and caspase-9 were analyzed.

RESULTSDown-regulation of TIPE2 promoted the apoptosis of CD4T lymphocytes in siTIPE2-burn group, in which the protein expressions of P-smad2/P-Smad3 decreased, Bcl-2 expression increased and Bim expression decreased significantly as compared with the other groups (P<0.01 or 0.05). The mitochondrial membrane potential and cytochrome C expression in CD4T cells were down-regulated in siTIPE2-burn group (P<0.05) with a lowered caspase-3 activity compared with TIPE2-burn group (P<0.01) and decreased caspase-8 and caspase-9 compared with the other groups (P<0.05). The apoptosis rate was the highest in TIPE2-burn group, whose Smad2/Smad3 was higher than that in the sham group (P<0.05) and the expression of P-smad2/P-Smad3 significantly increased compared with the other groups (P<0.05). In TIPE2-burn group, the mitochondrial membrane potential in CD4T cells was decreased (P<0.01), the expression of cytochrome C increased markedly (P<0.01), and the activities of caspase-3, caspase-8, and caspase-9 were all obviously higher than those in the other groups (P<0.05).

CONCLUSIONAs an important immunoregulatory molecule, TIPE2 can promote the apoptosis of CD4T lymphocyte in mice with sever burn injury.

Animals ; Apoptosis ; Burns ; immunology ; CD4-Positive T-Lymphocytes ; cytology ; Caspase 3 ; metabolism ; Caspase 8 ; metabolism ; Caspase 9 ; metabolism ; Down-Regulation ; Intracellular Signaling Peptides and Proteins ; metabolism ; Male ; Mice ; Smad2 Protein ; metabolism ; Smad3 Protein ; metabolism ; Spleen

Analysis of the T-cell receptor (TCR) repertoire of innate CD4+ T cells selected by major histocompatibility complex (MHC) class II-dependent thymocyte-thymocyte (T-T) interaction (T-T CD4+ T cells) is essential for predicting the characteristics of the antigens that bind to these T cells and for distinguishing T-T CD4+ T cells from other types of innate T cells. Using the TCRmini Tg mouse model, we show that the repertoire of TCRalpha chains in T-T CD4+ T cells was extremely diverse, in contrast to the repertoires previously described for other types of innate T cells. The TCRalpha chain sequences significantly overlapped between T-T CD4+ T cells and conventional CD4+ T cells in the thymus and spleen. However, the diversity of the TCRalpha repertoire of T-T CD4+ T cells seemed to be restricted compared with that of conventional CD4+ T cells. Interestingly, the frequency of the parental OT-II TCRalpha chains was significantly reduced in the process of T-T interaction. This diverse and shifted repertoire in T-T CD4+ T cells has biological relevance in terms of defense against diverse pathogens and a possible regulatory role during peripheral T-T interaction.
Amino Acid Sequence ; Animals ; Antigens, Surface/metabolism ; CD4-Positive T-Lymphocytes/cytology/*immunology/*metabolism ; Cell Communication ; Cell Differentiation/genetics/immunology ; Clonal Evolution ; Histocompatibility Antigens Class II/*immunology ; *Immunity, Innate ; Immunophenotyping ; Lymphocyte Count ; Mice ; Mice, Knockout ; Mice, Transgenic ; Peptide Fragments/chemistry ; Phenotype ; Receptors, Antigen, T-Cell/chemistry/*genetics/metabolism ; Receptors, Antigen, T-Cell, alpha-beta/chemistry/genetics ; Spleen/cytology ; Thymocytes/cytology/immunology/metabolism

Heat-shock protein (Hsp) 70 potentiates specific immune responses to some antigenic peptides fused to it. Here, the prokaryotic plasmids harboring the envelope glycoprotein E0 gene of classical swine fever virus (CSFV) and/or the Hsp70 gene of Haemophilus parasuis were constructed and expressed in Escherichia coli Rosseta 2(R2). The fusion proteins were then purified. Groups of Balb/c mice were immunized with these fusion proteins, respectively, and sera collected 7 days after the third immunization. Immune effects were determined via an enzyme-linked immunosorbent assay and flow cytometric analyses. E0-Hsp70 fusion protein and E0+Hsp70 mixture significantly improved the titer of E-specific antibody, levels of CD4+ and CD8+ T cells, and release of interferon-γ. These findings suggested that Hsp70 can significantly enhance the immune effects of the envelope glycoprotein E0 of CSFV, thereby laying the foundation of further application in pigs.
Animals ; Antibodies, Viral ; blood ; CD4-Positive T-Lymphocytes ; cytology ; immunology ; CD8-Positive T-Lymphocytes ; cytology ; immunology ; Cell Proliferation ; Classical swine fever virus ; genetics ; Female ; HSP70 Heat-Shock Proteins ; genetics ; immunology ; Haemophilus parasuis ; genetics ; Immunization ; Interferon-gamma ; metabolism ; Mice ; Mice, Inbred BALB C ; Plasmids ; genetics ; Recombinant Fusion Proteins ; genetics ; immunology ; Viral Envelope Proteins ; genetics

OBJECTIVETo investigate the mechanisms underlying the ability ofheparin-treated dendritic cells (DCs) to promote Th0 to Th1 differentiation in chronic hepatitis B (CHB).

METHODSPeripheral blood mononuclear cells (PBMCs) were isolated from CHB patients and cultured in RPMI-1640 with recombinant GM-CSF and IL-4 with or without heparin to obtain DCs for study. The levels of Toll-like receptors (TLRs) on the DCs were measured using FACS and qPCR techniques.DC subsets with high expression of TLRs were selected for analysis of functional changes by treatment with the corresponding TLR-siRNA. The CD4+ T cell subpopulation was purified from peripheral blood by Dynal immunomagnetic beads, and then the production of IL-12 by DCs in the presence of poly(I:C) or R848 and ofIFN and IL-4 by Th cells co-cultured with DCs was evaluated by ELISA. The t-test was used for statistical analysis.

RESULTSTLR3 expression, and not expression of TLR 7 or TLR8,was significantly increased in heparin-treated DCs as compared to levels detected in the DCs without heparin treatment (t =2.849,P less than 0.05;t =3.027,P less than 0.05). The level of IL-12 produced by heparin-treated DCs stimulated with poly(I:C) was obviously higher than that produced by DCs without heparin treatment and stimulated with poly(I: C) (t =8.68,P less than 0.01) or with R848 (t =19.01,P less than 0.01). However, the IL-12 production by TLR3-siRNA transfected-DCs was significantly reduced (t =31.49, P less than 0.01).When Th cells from allogenic patients with CHB were co-cultured with the TLR3-siRNA transfectedDCs, the frequency ofCD4+ IFN+ cells was significantly reduced (1.64+/-0.57% vs.6.31+/-0.88%,P less than 0.01),as was the capability of Thl to generate IFNg (t =20.83,Pless than 0.01).

CONCLUSIONHeparin may have up-regulated the TLR3 expression level of DCs, and sequentially promoted Th0 to Th1 differentiation.

CD4-Positive T-Lymphocytes ; cytology ; Cell Differentiation ; Coculture Techniques ; Dendritic Cells ; cytology ; Granulocyte-Macrophage Colony-Stimulating Factor ; pharmacology ; Heparin ; pharmacology ; Hepatitis B, Chronic ; immunology ; Humans ; Interferon-gamma ; metabolism ; Interleukin-12 ; metabolism ; Interleukin-4 ; pharmacology ; Monocytes ; cytology ; Recombinant Proteins ; pharmacology ; Toll-Like Receptor 3 ; metabolism

OBJECTIVE: To evaluate therapeutic eff ect of siRNA-HDAC5 on non-obese diabetic (NOD) mice by using small interference RNA (siRNA) technique to knock down the expression of HDAC5 in spleen CD4+ T cells. METHODS: NOD mice, 12-weeks old, were randomly divided into 3 groups and were given normal saline, siRNA-Control or siRNA-HDAC5 through caudal vein injection. The spleens and other samples were collected at the 18th, 24th or 30th week. The blood glucose was tested by blood glucose meter. The urinary albumin and serum levels of IL-1, IL-6, IL-18, and TNF-α were detected by ELISA. The mRNA levels of CD11a, CCR5, and CX3CR1 in spleen CD4+ T cells were measured by quantitative Real-time PCR. The HDAC5 protein level in spleen CD4+ T cell was detected by Western blot. RESULTS: Compared with the control group, the siRNA-HDAC5 group showed a significant decrease in blood glucose, urine albumin excretion rate, serum cytokine and the mRNA levels of CD11a, CCR5, and CX3CR1, consist with the decrease in protein level of HDAC5. CONCLUSION Inhibition of HDAC5 expression in NOD mice could effectively alleviate the onset and development of kidney damage caused by diabetes.
Animals ; CD11a Antigen ; metabolism ; CD4-Positive T-Lymphocytes ; metabolism ; CX3C Chemokine Receptor 1 ; Cytokines ; blood ; Diabetes Mellitus, Experimental ; genetics ; therapy ; Enzyme-Linked Immunosorbent Assay ; Histone Code ; Histone Deacetylases ; genetics ; Mice ; Mice, Inbred NOD ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; therapeutic use ; Random Allocation ; Real-Time Polymerase Chain Reaction ; Receptors, CCR5 ; metabolism ; Receptors, Chemokine ; metabolism ; Spleen ; cytology

PURPOSE: This study was done to evaluate the effects of psychosocial interventions on cortisol and immune response in adult patients with cancer. METHODS: MEDLINE via PubMed, Cochrane Library CENTRAL, EMBASE, CINAHL and domestic electronic databases were searched. Twenty controlled trials (11 randomized and 9 non-randomized trials) met the inclusion criteria with a total of 862 participants. Methodological quality was assessed using the Cochrane's Risk of Bias for randomized studies and the Risk of Bias Assessment tool for non randomized studies. Data were analyzed using the RevMan 5.2.11 program of Cochrane library. RESULTS: Overall, study quality was moderate to high. The weighted average effect size across studies was -0.32 (95% CI [-0.56, -0.07], p=.010, I2=45%) for cortisol concentration, -0.62 (95%CI [-0.96,-0.29], p<.001, I2=0%) for T lymphocyte (CD3) and -0.45 (95%CI [-0.74, -0.16], p=.003, I2=0%) for Th lymphocyte (CD4) numbers. Psychosocial interventions were not effective for Tc lymphocyte (CD4), NK cell, monocyte, and cytokine response. CONCLUSION: Although these results provide only small evidence of successful immune modulation, they support the conclusion that psychosocial interventions can assist cancer patients in reducing emotional distress and improving immune response.
CD4-Positive T-Lymphocytes/cytology/immunology ; Cytokines/metabolism ; Databases, Factual ; Humans ; Hydrocortisone/*analysis ; Killer Cells, Natural/cytology/immunology ; Monocytes/cytology/immunology ; Neoplasms/metabolism/pathology/*therapy ; Psychotherapy ; T-Lymphocytes/cytology/*immunology

OBJECTIVEParkinson's disease (PD), a neurodegenerative disorder, has been reported to be associated with brain neuroinflammation in its pathogenesis. Herein, changes in peripheral immune system were determined to better understand PD pathogenesis and provide possible target for treatment of PD through improvement of immune disorder.

METHODS1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was intraperitoneally injected into mice to prepare PD model. Expression levels of pro-inflammatory and anti-inflammatory cytokines and transcription factors of CD4+ T lymphocyte subsets in spleen and mesenteric lymph nodes and concentrations of the cytokines in serum were examined on day 7 after MPTP injection. Percentages of CD4+ T lymphocyte subsets were measured by flow cytometry.

RESULTSMPTP induced PD-like changes such as motor and behavioral deficits and nigrostriatal impairment. Expression levels of the pro-inflammatory cytokines including interferon (IFN)-γ, interleukin (IL)-2, IL-17 and IL-22, in spleen and mesenteric lymph nodes were upregulated and their concentrations in serum were elevated in PD progression. But, the concentrations of the anti-inflammatory cytokines including IL-4, IL-10 and transforming growth factor (TGF)-β were not altered in the two lymphoid tissues or serum of PD mice. In addition, expression of T-box in T cells (T-bet), the specific transcription factor of helper T (Th) 1 cells, was downregulated, but expression of transcription factor forkhead box p3 (Foxp3), the transcription factor of regulatory T (Treg) cells, was upregulated. In support of the results, the numbers of IFN-γ-producing CD4+ cells (Th1 cells) were reduced but CD4+CD25+ cells (Treg cells) were elevated in both the lymphoid tissues of PD mice.

CONCLUSIONPD has a dysfunction of peripheral immune system. It manifests enhancement of proinflammatory response and CD4+ T cell differentiation bias towards Treg cells away from Th1 cells.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine ; Animals ; CD4-Positive T-Lymphocytes ; pathology ; Cell Differentiation ; Cytokines ; blood ; Disease Models, Animal ; Flow Cytometry ; Forkhead Transcription Factors ; metabolism ; Interferon-gamma ; blood ; Interleukin-10 ; blood ; Interleukin-17 ; blood ; Interleukin-2 ; blood ; Interleukin-4 ; blood ; Interleukins ; blood ; Lymph Nodes ; cytology ; Lymphocyte Activation ; Mice ; Parkinson Disease ; immunology ; physiopathology ; Spleen ; cytology ; T-Box Domain Proteins ; metabolism ; T-Lymphocytes, Regulatory ; Th1 Cells ; Transforming Growth Factor beta ; blood

Myeloid-related protein (MRP)8/MRP14 is an endogenous Toll-like receptor 4 (TLR4) ligand and is abundant in synovial fluid (SF) of rheumatoid arthritis (RA) patients. Belonging to damage-associated molecular patterns, it amplifies proinflammatory mediators and facilitates a wide range of inflammatory and autoimmune diseases. Interleukin (IL)-17-producing T-helper (Th)17 cells have a crucial role in RA pathogenesis, and IL-6 is the key factor promoting Th17 differentiation. We investigated whether the level of MRP8/MRP14 is positively associated with IL-6 and IL-17 levels in RA SF and found that MRP8/MRP14 level had a significant correlation with IL-6 and IL-17 levels in RA SF. We also observed that MRP8-induced IL-17 production by peripheral blood mononuclear cells but MRP14 did not. Upon stimulation with MRP8, IL-6 production was enhanced by RA fibroblast-like synoviocytes (FLS) and was further elevated by coculturing RA FLS with activated CD4+ T cells. Moreover, we demonstrated that MRP8-activated IL-6 production by RA FLS promoted differentiation of Th17 cells using the coculture system consisting of CD4+ T cells and RA FLS. In addition, IL-6 blockade attenuated Th17 polarization of CD4+ T cells in the cocultures. Inhibitor studies revealed that MRP8 increased IL-6 production in RA FLS via TLR4/phosphoinositide 3-kinase/nuclear factor-kappaB and mitogen-activated protein kinase signaling pathways. Our results show that MRP8 has a crucial role in stimulating IL-6 expression by RA FLS, and subsequently promotes Th17 differentiation in RA, suggesting that neutralizing MRP8 level in RA synovium may be an effective therapeutic strategy in RA treatment.
ATP-Binding Cassette Transporters/*metabolism ; Adult ; Aged ; Arthritis, Rheumatoid/*pathology ; CD4-Positive T-Lymphocytes/metabolism ; Calgranulin B/metabolism ; Cell Differentiation/*immunology ; Fibroblasts/*metabolism/pathology ; Humans ; Inflammation Mediators/metabolism ; Interleukin-17/metabolism ; Interleukin-6/*biosynthesis ; Middle Aged ; Signal Transduction/immunology ; Synovial Fluid/cytology ; Synovial Membrane/metabolism/pathology ; Th17 Cells/*pathology ; Toll-Like Receptor 4/metabolism ; *Up-Regulation