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Clinical Immunology (Orlando, Fla.) Feb 2021The study aimed to understand the molecular mechanisms that might lead to differences in the glucocorticoid response during sepsis. (Observational Study)
Observational Study
PURPOSE
The study aimed to understand the molecular mechanisms that might lead to differences in the glucocorticoid response during sepsis.
METHODS
Patients diagnosed with sepsis (n = 198) and 40 healthy controls were enrolled. Glucocorticoid receptor (GR) expression in circulating leukocytes and plasma levels of adrenocorticotropic hormone and cortisol on days 1 and 7 were measured in all participants. Expression profiling of 16 genes associated with GR expression in peripheral blood mononuclear cells (PBMCs) in 12 healthy controls and 26 patients with sepsis was performed by PCR.
RESULTS
Cortisol levels were higher in patients with sepsis than in healthy controls on day 1 after admission and recovered to normal levels by day 7. GR expression was gradually downregulated in leukocyte subsets. Non-survivors showed lower GR and higher cortisol levels than survivors. GRα expression was lower in patients with sepsis than in controls, whereas GRβ showed the opposite trend. MicroRNAs related to GR resistance and suppression were altered in PBMCs during sepsis.
CONCLUSION
Patients with sepsis showed upregulated plasma cortisol levels along with downregulated GR expression on various leukocyte subtypes, portending poor cortisol response and outcome. Changes in GR-regulatory miRNAs may be responsible for GR low expression.
Topics: Adrenocorticotropic Hormone; Aged; Aged, 80 and over; Cells, Cultured; Cohort Studies; Female; Gene Expression Regulation; Glucocorticoids; Humans; Hydrocortisone; Leukocytes, Mononuclear; Male; MicroRNAs; Middle Aged; Receptors, Glucocorticoid; Sepsis; Transcriptome; Treatment Outcome
PubMed: 33352295
DOI: 10.1016/j.clim.2020.108660 -
Frontiers in Immunology 2020Human cytomegalovirus (CMV) is a highly prevalent herpesvirus, particularly in sub-Saharan Africa, where it is endemic from infancy. The T cell response against CMV is...
Human cytomegalovirus (CMV) is a highly prevalent herpesvirus, particularly in sub-Saharan Africa, where it is endemic from infancy. The T cell response against CMV is important in keeping the virus in check, with CD8 T cells playing a major role in the control of CMV viraemia. Human leukocyte antigen (HLA) B44:03-positive individuals raise a robust response against the NEGVKAAW (NW8) epitope, derived from the immediate-early-2 (IE-2) protein. We previously showed that the T cell receptor (TCR) repertoire raised against the NW8-HLA-B44:03 complex was oligoclonal and characterised by superdominant clones, which were shared amongst unrelated individuals (i.e., "public"). Here, we address the question of how stable the CMV-specific TCR repertoire is over the course of infection, and whether substantial differences are evident in TCR repertoires in children, compared with adults. We present a longitudinal study of four HIV/CMV co-infected mother-child pairs, who in each case express HLA-B44:03 and make responses to the NW8 epitope, and analyse their TCR repertoire over a period spanning more than 10 years. Using high-throughput sequencing, the paediatric CMV-specific repertoire was found to be highly diverse. In addition, paediatric repertoires were remarkably similar to adults, with public TCR responses being shared amongst children and adults alike. The CMV-specific repertoire in both adults and children displayed strong fluctuations in TCR clonality and repertoire architecture over time. Previously characterised superdominant clonotypes were readily identifiable in the children at high frequency, suggesting that the distortion of the CMV-specific repertoire is incurred as a direct result of CMV infection rather than a product of age-related "memory inflation." Early distortion of the TCR repertoire was particularly apparent in the case of the TCR-β chain, where oligoclonality was low in children and positively correlated with age, a feature we did not observe for TCR-α. This discrepancy between TCR-α and -β chain repertoire may reflect differential contribution to NW8 recognition. Altogether, the results of the present study provide insight into the formation of the TCR repertoire in early life and pave the way to better understanding of CD8 T cell responses to CMV at the molecular level.
Topics: Adolescent; Adult; Age Factors; Antigens, Viral; CD8-Positive T-Lymphocytes; Child; Child, Preschool; Coinfection; Cytomegalovirus; Cytomegalovirus Infections; Epitopes, T-Lymphocyte; Female; HIV Infections; HLA Antigens; High-Throughput Nucleotide Sequencing; Humans; Infant; Leukocytes, Mononuclear; Peptides; Receptors, Antigen, T-Cell; T-Cell Antigen Receptor Specificity; T-Lymphocytes; Viral Load; Young Adult
PubMed: 33101265
DOI: 10.3389/fimmu.2020.01587 -
Blood Purification 2023Uremic retention solutes have been alleged to induce the apoptotic program of different cell types, including peripheral blood mononuclear leukocytes (PBL), which may...
INTRODUCTION
Uremic retention solutes have been alleged to induce the apoptotic program of different cell types, including peripheral blood mononuclear leukocytes (PBL), which may contribute to uremic leukopenia and immune dysfunction.
METHODS
The molecular effects of these solutes were investigated in uremic PBL (u-PBL) and mononuclear cell lines (THP-1 and K562) exposed to the high molecular weight fraction of uremic plasma (u-HMW) prepared by in vitro ultrafiltration with 50 kDa cut-off microconcentrators.
RESULTS
u-PBL show reduced cell viability and increased apoptotic death compared to healthy control PBL (c-PBL). u-HMW induce apoptosis both in u-PBL and c-PBL, as well as in mononuclear cell lines, also stimulating cellular H2O2 formation and secretion, IRE1-α-mediated endoplasmic reticulum stress signaling, and JNK/cJun pathway activation. Also, u-HMW induce autophagy in THP-1 monocytes. u-PBL were characterized by the presence in their cellular proteome of the main proteins and carbonylation targets of u-HMW, namely albumin, transferrin, and fibrinogen, and by the increased expression of receptor for advanced glycation end-products, a scavenger receptor with promiscuous ligand binding properties involved in leukocyte activation and endocytosis.
CONCLUSIONS
Large uremic solutes induce abnormal endocytosis and terminal alteration of cellular proteostasis mechanisms in PBL, including UPR/ER stress response and autophagy, ultimately activating the JNK-mediated apoptotic signaling of these cells. These findings describe the suicidal role of immune cells in facing systemic proteostasis alterations of kidney disease patients, a process that we define as the immuno-proteostasis response of uremia.
Topics: Humans; Leukocytes, Mononuclear; Proteostasis; Receptor for Advanced Glycation End Products; Hydrogen Peroxide; Proteins; Apoptosis
PubMed: 37703866
DOI: 10.1159/000533309 -
Annals of Medicine Dec 2024Accumulating evidence suggests that differentially expressed circular RNAs (circRNAs) play critical roles in immune cells of systemic lupus erythematosus (SLE) patients....
OBJECTIVE
Accumulating evidence suggests that differentially expressed circular RNAs (circRNAs) play critical roles in immune cells of systemic lupus erythematosus (SLE) patients. Hsa_circ_0000479 has been studied in the field of cancer and infection, whereas seldom studied in autoimmune diseases. The aim of this study was to investigate the role and clinical value of neutrophil hsa_circ_0000479 in SLE.
METHODS
The expression levels of hsa_circ_0000479 in both healthy individuals and SLE patients' neutrophils were detected by qPCR and compared with those in peripheral blood mononuclear cells (PBMCs) . In addition, the correlation of hsa_circ_0000479 levels in neutrophils with the clinical and immunological features of SLE patients was also analysed.
RESULTS
The expression levels of hsa_circ_0000479 in the patients with SLE were significantly higher in neutrophils than that of PBMCs, and also significantly higher than that in healthy controls (HCs). Moreover, the expression levels of hsa_circ_0000479 in neutrophils were negatively associated with absolute neutrophil count and complement 3 (C3), whereas positively correlated with anti-dsDNA and anti-nucleosome antibodies in SLE. In addition, SLE patients with higher levels of hsa_circ_0000479 demonstrated more several clinical manifestations, including Raynaud's phenomenon, alopecia and leucopenia.
CONCLUSIONS
Hsa_circ_0000479 is up-regulated in neutrophils of SLE patients, and is also associated with several important laboratory indicators and clinical manifestations, suggesting that hsa_circ_0000479 in neutrophils was one of probable factors involved in the pathogenesis of SLE with potential clinical value.
Topics: Humans; Neutrophils; Leukocytes, Mononuclear; RNA, Circular; Lupus Erythematosus, Systemic; Leukocyte Count
PubMed: 38300888
DOI: 10.1080/07853890.2024.2309607 -
Redox Biology Apr 2024Low selenium concentrations are associated with worse outcomes in heart failure (HF). However, the underlying pathophysiologic mechanisms remain incompletely understood....
BACKGROUND
Low selenium concentrations are associated with worse outcomes in heart failure (HF). However, the underlying pathophysiologic mechanisms remain incompletely understood. Therefore, we aimed to contrast serum selenium concentrations to blood biomarker and transcriptomic profiles in patients with HF.
METHODS
Circulating biomarkers, whole blood transcriptomics and serum selenium measurements in a cohort of 2328 patients with HF were utilized. Penalized linear regression and gene expression analysis were used to assess biomarker and transcriptomics profiles, respectively. As a proof-of-principle, potential causal effects of selenium on excreted cytokines concentrations were investigated using human peripheral blood mononuclear cells (PBMCs).
RESULTS
Mean selenium levels were 60.6 μg/L in Q1 and 122.0 μg/L in Q4. From 356 biomarkers and 20 clinical features, the penalized linear regression model yielded 44 variables with <5 % marginal false discovery rate as predictors of serum selenium. Biomarkers associated positively with selenium concentrations included: epidermal growth factor receptor (EGFR), IFN-gamma-R1, CD4, GDF15, and IL10. Biomarkers associated negatively with selenium concentrations included: PCSK9, TNFSF13, FGF21 and PAI. Additionally, 148 RNA transcripts were found differentially expressed between high and low selenium status (P<0.05; log-fold-change<|0.25|). Enrichment analyses of the selected biomarkers and RNA transcripts identified similar enriched processes, including regulation processes of leukocyte differentiation and activation, as well as cytokines production. The mRNA expression of two selenoproteins (MSRB1 and GPX4) were strongly correlated with serum selenium, while GPX4, SELENOK, and SELENOS were associated with prognosis. In the in-vitro setting, PBMCs supplemented with selenium showed significantly lower abundance of several (pro-)inflammatory cytokines.
CONCLUSION
These data suggest that immunoregulation is an important mechanism through which selenium might have beneficial roles in HF. The beneficial effects of higher serum selenium concentrations are likely because of global immunomodulatory effects on the abundance of cytokines. MSRB1 and GPX4 are potential modulators of and should be pursued in future research.
Topics: Humans; Selenium; Proprotein Convertase 9; Transcriptome; Leukocytes, Mononuclear; Biomarkers; Gene Expression Profiling; Heart Failure; Cytokines; RNA
PubMed: 38295576
DOI: 10.1016/j.redox.2024.103046 -
The Journal of Allergy and Clinical... Sep 2018Hereditary angioedema (HAE) caused by C1-inhibitor deficiency is a lifelong illness characterized by recurrent acute attacks of localized skin or mucosal edema....
BACKGROUND
Hereditary angioedema (HAE) caused by C1-inhibitor deficiency is a lifelong illness characterized by recurrent acute attacks of localized skin or mucosal edema. Activation of the kallikrein/bradykinin pathway at the endothelial cell level has a relevant pathogenetic role in acute HAE attacks. Moreover, other pathways are involved given the variable clinical expression of the disease in different patients.
OBJECTIVE
We sought to explore the involvement of other putative genes in edema formation.
METHODS
We performed a PBMC microarray gene expression analysis on RNA isolated from patients with HAE during an acute attack and compared them with the transcriptomic profile of the same patients in the remission phase.
RESULTS
Gene expression analysis identified 23 genes significantly modulated during acute attacks that are involved primarily in the natural killer cell signaling and leukocyte extravasation signaling pathways. Gene set enrichment analysis showed a significant activation of relevant biological processes, such as response to external stimuli and protein processing (q < 0.05), suggesting involvement of PBMCs during acute HAE attacks. Upregulation of 2 genes, those encoding adrenomedullin and cellular receptor for urokinase plasminogen activator (uPAR), which occurs during an acute attack, was confirmed in PBMCs of 20 additional patients with HAE by using real-time PCR. Finally, in vitro studies demonstrated the involvement of uPAR in the generation of bradykinin and endothelial leakage.
CONCLUSIONS
Our study demonstrates the increase in levels of adrenomedullin and uPAR in PBMCs during an acute HAE attack. Activation of these genes usually involved in regulation of vascular tone and in inflammatory response might have a pathogenic role by amplifying bradykinin production and edema formation in patients with HAE.
Topics: Acute Disease; Adolescent; Adrenomedullin; Adult; Aged; Angioedemas, Hereditary; Cells, Cultured; Female; Human Umbilical Vein Endothelial Cells; Humans; Jurkat Cells; Leukocytes, Mononuclear; Male; Middle Aged; Transcriptome; Urokinase-Type Plasminogen Activator
PubMed: 29729940
DOI: 10.1016/j.jaci.2018.03.016 -
Investigative Ophthalmology & Visual... Oct 2023Eye inflammation may occur in patients with inherited retinal dystrophies (IRDs) and is seen frequently in IRDs associated with mutations in the CRB1 gene. The purpose...
PURPOSE
Eye inflammation may occur in patients with inherited retinal dystrophies (IRDs) and is seen frequently in IRDs associated with mutations in the CRB1 gene. The purpose of this study was to determine the types of inflammatory cells involved in IRDs, by deep profiling the composition of peripheral blood mononuclear cells of patients with a CRB1-associated IRD.
METHODS
This study included 33 patients with an IRD with confirmed CRB1 mutations and 32 healthy controls. A 43-parameter flow cytometry analysis was performed on peripheral blood mononuclear cells isolated from venous blood. FlowSOM and manual Boolean combination gating were used to identify and quantify immune cell subsets.
RESULTS
Comparing patients with controls revealed a significant increase in patients in the abundance of circulating CD4+ T cells and CD8+ T cells that express sialyl Lewis X antigen. Furthermore, we detected a decrease in plasmacytoid dendritic cells and an IgA+CD24+CD38+ transitional B-cell subset in patients with an IRD.
CONCLUSIONS
Patients with a CRB1-associated IRD show marked changes in blood leukocyte composition, affecting lymphocyte and dendritic cell populations. These results implicate inflammatory pathways in the disease manifestations of IRDs.
Topics: Humans; Leukocytes, Mononuclear; Eye Proteins; Retinal Dystrophies; Mutation; Eye Abnormalities; T-Lymphocytes; Membrane Proteins; Nerve Tissue Proteins
PubMed: 37792335
DOI: 10.1167/iovs.64.13.6 -
Nanotoxicology Mar 2024The growing application of silver nanoparticles (AgNPs) in consumer, healthcare, and industrial products has raised concern over potential health implications due to...
The growing application of silver nanoparticles (AgNPs) in consumer, healthcare, and industrial products has raised concern over potential health implications due to increasing exposure. The evaluation of the immune response to nanomaterials is one of the key criteria to assess their biocompatibility. There are well-recognized sex-based differences in innate and adaptive immune responses. However, there is limited information available using human models. The aim was to investigate the potential sex-based differences in immune functions after exposure to AgNPs using human peripheral blood mononuclear cells (PBMCs) and plasma from healthy donors. These functions include inflammasome activation, cytokine expression, leukocyte proliferation, chemotaxis, plasma coagulation, and complement activation. AgNPs were characterized by dynamic light scattering and transmission electron microscopy. Inflammasome activation by AgNPs was measured after 6- and 24-hours incubations. AgNPs-induced inflammasome activation was significantly higher in the females, especially for the 6-hour exposure. No sex-based differences were observed for Ag ions controls. Younger donors exhibited significantly more inflammasome activation than older donors after 24-hours exposure. IL-10 was significantly suppressed in males and females after exposure. AgNPs suppressed leukocyte proliferation similarly in males and females. No chemoattractant effects, no alterations in plasma coagulation, or activation of the complement were observed after AgNPs exposure. In conclusion, the results highlight that there are distinct sex-based differences in inflammasome activation after exposure to AgNPs in human PBMCs. The results highlight the importance of considering sex-based differences in inflammasome activation induced by exposure to AgNPs in any future biocompatibility assessment for products containing AgNPs.
Topics: Humans; Silver; Metal Nanoparticles; Female; Male; Leukocytes, Mononuclear; Adult; Inflammasomes; Middle Aged; Cell Proliferation; Cytokines; Sex Factors; Young Adult
PubMed: 38444264
DOI: 10.1080/17435390.2024.2323070 -
Veterinary Immunology and... Apr 2022A more complete understanding of canine T-lymphocyte immunity is necessary for improving diagnostic and therapeutic approaches to canine diseases, developing cell-based...
A more complete understanding of canine T-lymphocyte immunity is necessary for improving diagnostic and therapeutic approaches to canine diseases, developing cell-based canine immunotherapeutics, and evaluating dogs as large mammal models for comparative immunology research. The aim of this study was to utilize CD45RA (indicating antigen inexperience) and CD62L (indicating lymph node homing capability), to quantify canine memory T-cell subsets in healthy dogs and dogs with various diseases. Peripheral blood mononuclear cells (PBMCs) were prospectively collected from dogs belonging to one of four groups:dermatologic inflammation (n = 9), solid tumors (n = 9), lymphoma (n = 9), and age-/weight-matched healthy control dogs (n = 15). Dogs receiving prednisone or any other immunomodulating medication within two weeks were excluded. Flow cytometry was performed and T-cell subsets were defined as CD4+ or CD8+, and naïve (TN), central memory (CM), effector memory (EM), or terminal effector memory re-expressing CD45RA (TEMRA). T-cell subset proportions were compared between each disease group and their healthy age-/weight-matched controls using a Mann-Whitney test. Significantly increased %CD8+ TN (P = 0.036) and decreased %CD8+ TEMRA (P = 0.045) were detected in dogs with dermatologic inflammation compared to healthy controls. Furthermore, %CD4+ TN positively correlated with Canine Atopic Dermatitis Extent and Severity Index (CADESI) score within the inflammation group (ρ = 0.817, P = 0.011). No significant differences between either cancer group and their healthy controls were detected. Taken together, these data indicate that dermatologic inflammation can alter proportions of peripheral blood T-cell subsets, possibly due to the migration of antigen-specific T-cells into tissues. Furthermore, these findings support the utility of CD45RA and CD62L in characterizing clinical canine immune responses.
Topics: Animals; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Dog Diseases; Dogs; Immunologic Memory; L-Selectin; Leukocyte Common Antigens; Leukocytes, Mononuclear; Memory T Cells; Neoplasms; Skin Diseases
PubMed: 35255296
DOI: 10.1016/j.vetimm.2022.110401 -
Scientific Reports Nov 2016Interactions between endothelial selectins and the leukocyte counter-receptor PSGL1 mediates leukocyte recruitment to inflammation sites. PSGL1 is highly sialylated,...
Interactions between endothelial selectins and the leukocyte counter-receptor PSGL1 mediates leukocyte recruitment to inflammation sites. PSGL1 is highly sialylated, making it a potential ligand for Siglec-5, a leukocyte-receptor that recognizes sialic acid structures. Binding assays using soluble Siglec-5 variants (sSiglec-5/C4BP and sSiglec-5/Fc) revealed a dose- and calcium-dependent binding to PSGL1. Pre-treatment of PSGL1 with sialidase reduced Siglec-5 binding by 79 ± 4%. In confocal immune-fluorescence assays, we observed that 50% of Peripheral Blood Mononuclear Cells (PBMCs) simultaneously express PSGL1 and Siglec-5. Duolink-proximity ligation analysis demonstrated that PSGL1 and Siglec-5 are in close proximity (<40 nm) in 31 ± 4% of PBMCs. In vitro perfusion assays revealed that leukocyte-rolling over E- and P-selectin was inhibited by sSiglec-5/Fc or sSiglec-5/C4BP, while adhesion onto VCAM1 was unaffected. When applied to healthy mice (0.8 mg/kg), sSiglec-5/C4BP significantly reduced the number of rolling leukocytes under basal conditions (10.9 ± 3.7 versus 23.5 ± 9.3 leukocytes/field/min for sSiglec-5/C4BP-treated and control mice, respectively; p = 0.0093). Moreover, leukocyte recruitment was inhibited over a 5-h observation period in an in vivo model of TNFalpha-induced inflammation following injection sSiglec-5/C4BP (0.8 mg/kg). Our data identify PSGL1 as a ligand for Siglec-5, and soluble Siglec-5 variants appear efficient in blocking PSGL1-mediated leukocyte rolling and the inflammatory response in general.
Topics: Animals; Anti-Inflammatory Agents; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Disease Models, Animal; E-Selectin; Female; Humans; Inflammation; Lectins; Leukocyte Rolling; Leukocytes, Mononuclear; Membrane Glycoproteins; Mice, Inbred C57BL; P-Selectin; Protein Interaction Domains and Motifs; Solubility; Tumor Necrosis Factor-alpha
PubMed: 27892504
DOI: 10.1038/srep37953