Monocyte Receptor Research Articles

Pancreatic Adenocarcinoma Up-Regulated Factor (PAUF) Transforms Human Monocytes into Alternative M2 Macrophages with Immunosuppressive Action

Tumor-associated macrophages (TAMs) in the tumor microenvironment (TME) promote immune evasion, cancer cell proliferation, and metastasis. Ongoing research is focused on finding ways to prevent tumor growth by inhibiting TAM polarization, which has shown a correlation with unfavorable prognosis in clinical studies. Pancreatic adenocarcinoma up-regulated factor (PAUF) is a protein secreted from pancreatic cancer (PC) and acts as a TME modulator that affects the TME by acting on not only cancer cells but also stromal cells and immune cells. Tumor cells can evade the immune system by PAUF binding to Toll-like receptor (TLR) in monocytes, as this research shows. In this study, the examination centered around the recruitment of human monocytes by PAUF and the subsequent differentiation into macrophages. In an in vitro chemotaxis assay, PAUF induced chemotactic migration of TLR2-mediated monocytes. In addition, PAUF induced differentiation of monocytes into M2 macrophages, which was verified based on expressing surface markers and cytokines and morphological analysis. The inhibition of T cell proliferation and function was observed in differentiated M2 macrophages. To conclude, these findings indicate that PAUF functions as a promoter of cancer progression by regulating the recruitment and differentiation of macrophages within TMEs, ultimately causing immunosuppression.

2-AG-loaded and bone marrow-targeted PCL nanoparticles as nanoplatforms for hematopoietic cell line mobilization

BackgroundThe use of mobilizing agents for hematopoietic stem cell (HSC) transplantation is insufficient for an increasing number of patients. We previously reported lipid made endocannabinoid (eCB) ligands act on the human bone marrow (hBM) HSC migration in vitro, lacking long term stability to be therapeutic candidate. In this study, we hypothesized if a novel 2-AG-loaded polycaprolactone (PCL)-based nanoparticle delivery system that actively targets BM via phosphatidylserine (Ps) can be generated and validated.MethodsPCL nanoparticles were prepared by using the emulsion evaporation method and characterized by Zetasizer and scanning electron microscopy (SEM). The encapsulation efficiency and release profile of 2-AG were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The presence of cannabinoid receptors (CBRs) in HSCs and monocytes was detected by flow cytometry. Cell morphology and viability were assessed using transmission electron microscopy (TEM), SEM, and the WST-1 viability assay. The migration efficacy of the 2-AG and 2-AG-loaded nanoparticle delivery system on HSCs and HPSCs (TF-1a and TF-1) and monocytes (THP-1) was evaluated using a transwell migration assay.ResultsThe 140–225 nm PCL nanoparticles exhibited an increasing polydispersity index (PDI) after the addition of Ps and 2-AG, with a surface charge ranging from − 25 to -50 mV. The nanoparticles released up to 36% of 2-AG within the first 8 h. The 2-AG-Ps-PCL did not affect cellular viability compared to control on days 5 and 10. The HSCs and monocytes expressed CB1R and CB2R and revealed increased migration to media containing 1 µM 2-AG-Ps-PCL compared to control. The migration rate of the HSCs toward monocytes incubated with 1 µM 2-AG-Ps-PCL was higher than that of the monocytes of control. The 2-AG-Ps-PCL formulation provided a real time mobilization efficacy at 1 µM dose and 8 h time window via a specific CBR agonism.ConclusionThe newly generated and validated 2-AG-loaded PCL nanoparticle delivery system can serve as a stable, long lasting, targeted mobilization agent for HSCs and as a candidate therapeutic to be included in HSC transplantation (HSCT) protocols following scale-up in vivo preclinical and subsequent clinical trials.Graphical

CAMP signaling of Bordetella adenylate cyclase toxin blocks M-CSF triggered upregulation of iron acquisition receptors on differentiating CD14+ monocytes.

Bordetella pertussis infects the upper airways of humans and disarms host defense by the potent immuno-subversive activities of its pertussis (PT) and adenylate cyclase (CyaA) toxins. CyaA action near-instantly ablates the bactericidal activities of sentinel CR3-expressing myeloid phagocytes by hijacking cellular signaling pathways through the unregulated production of cAMP. Moreover, CyaA-elicited cAMP signaling also inhibits the macrophage colony-stimulating factor (M-CSF)-induced differentiation of incoming inflammatory monocytes into bactericidal macrophages. We show that CyaA/cAMP signaling via protein kinase A (PKA) downregulates the M-CSF-elicited expression of monocyte receptors for transferrin (CD71) and hemoglobin-haptoglobin (CD163), as well as the expression of heme oxygenase-1 (HO-1) involved in iron liberation from internalized heme. The impact of CyaA action on CD71 and CD163 levels in differentiating monocytes is largely alleviated by the histone deacetylase inhibitor trichostatin A (TSA), indicating that CyaA/cAMP signaling triggers epigenetic silencing of genes for micronutrient acquisition receptors. These results suggest a new mechanism by which B. pertussis evades host sentinel phagocytes to achieve proliferation on airway mucosa.IMPORTANCETo establish a productive infection of the nasopharyngeal mucosa and proliferate to sufficiently high numbers that trigger rhinitis and aerosol-mediated transmission, the pertussis agent Bordetella pertussis deploys several immunosuppressive protein toxins that compromise the sentinel functions of mucosa patrolling phagocytes. We show that cAMP signaling elicited by very low concentrations (22 pM) of Bordetella adenylate cyclase toxin downregulates the iron acquisition systems of CD14+ monocytes. The resulting iron deprivation of iron, a key micronutrient, then represents an additional aspect of CyaA toxin action involved in the inhibition of differentiation of monocytes into the enlarged bactericidal macrophage cells. This corroborates the newly discovered paradigm of host defense evasion mechanisms employed by bacterial pathogens, where manipulation of cellular cAMP levels blocks monocyte to macrophage transition and replenishment of exhausted phagocytes, thereby contributing to the formation of a safe niche for pathogen proliferation and dissemination.

Exaggerated Kawasaki disease-associated vasculitis in C-C Motif Chemokine Receptor 5 (CCR5) deficient mice is driven by Granulocyte Colony Stimulating Factor (G-CSF) overproduction and neutrophil formation and infiltration

Kawasaki disease (KD) is a rare but serious illness that primarily affects children. It is characterized by inflammation of the blood vessels throughout the body, including the coronary arteries (CA). Polymorphisms in CCR5 influence KD susceptibility and cardiovascular outcome, but the mechanisms are enigmatic yet. Thus, we aimed to explore the mechanisms by which polymorphisms in CCR5 aggravate the vascular injury in KD by using the Candida albicans water soluble (CAWS) fraction model. Male (6-10-weeks-old) CCR5 deficient mice (CCR5−/−) and their counterpart (CCR5+/+) were used. Cardiac single-cell transcriptomics (scRNAseq) analysis of both control and KD mice revealed an inflammatory landscape characterized by an abundance of macrophages, monocytes, and neutrophils. Additionally, our scRNAseq data indicated that CCR5 expression is predominantly observed in macrophages and monocytes in KD mice, whereas its ligands, CCL3 and CCL4, are primarily expressed in neutrophils. Our CellChat analysis uncovered robust intercommunication between neutrophils and macrophages and monocytes. This interaction involves the production of CCL3 and CCL4 by neutrophils, which act on CCR5 receptors in macrophages and monocytes. To validate this scRNAseq data, we analyzed the vasculitis levels in CA and immune cells content in CCR5+/+ and CCR5−/− mice with KD via histology and flow cytometry. CCR5−/− mice with KD exhibited aggravated vasculitis, increased neutrophil accumulation [(% in relation to 10^6 leukocytes) CCR5+/+: 2.5±1.7 n=4 vs. CCR5+/+ KD: 16.1±3.2 n=4], and CCR5−/− KD: 30.2±7.4 n=4), alongside cardiac senescence (3-fold rise in p21 expression) and a 2-fold increase in Caspase-3, indicating increased cell death compared to CCR5+/+ with KD. Mechanistically, our plasma proteome profile cytokine assay revealed that KD increases circulating IL-6 and circulating neutrophil, interestingly CCR5−/− mice with KD showed further circulating IL-6 and neutrophil along with G-CSF, which plays a critical role in stimulating the production and release of granulocytes, particularly neutrophils, from the bone marrow into the bloodstream. Thus, deficiency in CCR5 triggers a worse vasculitis in KD by regulating an over production of neutrophil by bone marrow via G-CSF, which in turn will lead to an exaggerated IL-6 production, further accumulation in CA, and aggravated cardiac damage. FAPESP (2022/06639-2), NHLBI-R00 (R00HL14013903), AHA (CDA857268 and 23DIVSUP1069230), Vascular Medicine Institute, the Hemophilia Center of Western Pennsylvania Vitalant, and Children's Hospital of Pittsburgh of the UPMC Health System. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Different Influence Pattern of Conventional and Alternative Sources of Smoking on Adhesion Molecules and Cytokine Secretion in THP-1 Monocytes.

Tobacco is a carcinogen that is closely associated with the occurrence of lung cancer and head and neck squamous cell carcinoma (HNSCC). The consumption of tobacco is also leading to alterations in different immune cell subtypes. However, the impact of different conventional and alternative smoking sources on human monocytes remains elusive. In this study, we investigated the influence of aqueous extracts of different sources of smoking (cigarettes; heated tobacco product IQOS; e-cigarettes with and without nicotine; nicotine pouches) on different monocytic adhesion molecules, chemokine receptors and checkpoint molecule PD-L1 by flow cytometry. Cytokine expression patterns were evaluated using human cytokine arrays and the human monocyte leukemia cell line THP-1 as a model. Data revealed differential effects of the analyzed conventional and alternative smoking devices on monocyte adhesion molecules and cytokine secretion. The examined smoking devices can be assigned to two differential monocyte activation patterns. Monocytes stimulated with aqueous extracts of cigarettes, e-cigarette without nicotine, and heat not burn product IQOS revealed distinct alterations of surface markers and cytokines compared to the monocyte activation pattern in response to aqueous extracts of nicotine, nicotine pouches, and e-cigarette with nicotine. Our data indicate differential immunological consequences of different conventional and alternative smoking sources with and without nicotine. Further comprehensive analysis as well as in vivo investigations on peripheral blood monocyte subsets from smoking individuals using different smoking sources are required to better understand the impact on monocyte characteristics, especially with regard to the development of cancer.

Genetic Contributions to Recovery following Brain Trauma: A Narrative Review.

Traumatic brain injury (TBI) is a frequently encountered form of injury that can have lifelong implications. Despite advances in prevention, diagnosis, monitoring, and treatment, the degree of recovery can vary widely between patients. Much of this is explained by differences in severity of impact and patient-specific comorbidities; however, even among nearly identical patients, stark disparities can arise. Researchers have looked to genetics in recent years as a means of explaining this phenomenon. It has been hypothesized that individual genetic factors can influence initial inflammatory responses, recovery mechanisms, and overall prognoses. In this review, we focus on cytokine polymorphisms, mitochondrial DNA (mtDNA) haplotypes, immune cells, and gene therapy given their associated influx of novel research and magnitude of potential. This discussion is prefaced by a thorough background on TBI pathophysiology to better understand where each mechanism fits within the disease process. Cytokine polymorphisms causing unfavorable regulation of genes encoding IL-1β, IL-RA, and TNF-α have been linked to poor TBI outcomes like disability and death. mtDNA haplotype H has been correlated with deleterious effects on TBI recovery time, whereas haplotypes K, T, and J have been depicted as protective with faster recovery times. Immune cell genetics such as microglial differentially expressed genes (DEGs), monocyte receptor genes, and regulatory factors can be both detrimental and beneficial to TBI recovery. Gene therapy in the form of gene modification, inactivation, and editing show promise in improving post-TBI memory, cognition, and neuromotor function. Limitations of this study include a large proportion of cited literature being focused on pre-clinical murine models. Nevertheless, favorable evidence on the role of genetics in TBI recovery continues to grow. We aim for this work to inform interested parties on the current landscape of research, highlight promising targets for gene therapy, and galvanize translation of findings into clinical trials.

Clinical Significance of Evaluation of Monocytic Receptors in Patients with Hepatitis C Virus Infection.

Monocytes in hepatitis C virus (HCV) infection play a critical role in chronic liver inflammation and fibrosis. We studied circulating monocytes and monocyte receptors in patients with HCV infection who were naive to treatment and those who received direct acting antiviral therapy and achieved sustained virological response. CD64+ CCR2+ (M1-like) and CD206+ CD163+ CX3CR1+ (M2-like) monocyte numbers and receptor expression were evaluated by flow cytometry. Higher expression of the monocyte chemokine receptor CCR2 predicted the severity of liver fibrosis, independent of successful treatment and viral clearance (R2 = 0.235, p = 0.002), whereas monocyte CX3CR1 expression was lower in both treated and untreated patients compared with controls (p = 0.011). The expression of the scavenger receptor CD163 was lower in patients with successful treatment (p = 0.005), supporting its role as a marker of treatment response. CD64+ CCR2+ (M1-like) and CD206+ CD163+ CX3CR1+ (M2-like) monocyte numbers were not altered with fibrosis progression or treatment response. Our findings reflect the diverse functions of monocytes in liver inflammation, fibrosis, and therapy. However, HCV clearance did not lead to complete monocyte reconstitution. Targeting monocytes and their chemokine receptors bears therapeutic potential to reduce liver fibrosis and improve disease outcome.

Neighborhood socioeconomic deprivation and individual-level socioeconomic status are associated with dopamine-mediated changes to monocyte subset CCR2 expression via a cAMP-dependent pathway

Social determinants of health (SDoH) include socioeconomic, environmental, and psychological factors that impact health. Neighborhood socioeconomic deprivation (NSD) and low individual-level socioeconomic status (SES) are SDoH that associate with incident heart failure, stroke, and cardiovascular mortality, but the underlying biological mechanisms are not well understood. Previous research has demonstrated an association between NSD, in particular, and key components of the neural-hematopoietic-axis including amygdala activity as a marker of chronic stress, bone marrow activity, and arterial inflammation. Our study further characterizes the role of NSD and SES as potential sources of chronic stress related to downstream immunological factors in this stress-associated biologic pathway. We investigated how NSD, SES, and catecholamine levels (as proxy for sympathetic nervous system activation) may influence monocytes which are known to play a significant role in atherogenesis. First, in an ex vivo approach, we treated healthy donor monocytes with biobanked serum from a community cohort of African Americans at risk for CVD. Subsequently, the treated monocytes were subjected to flow cytometry for characterization of monocyte subsets and receptor expression. We determined that NSD and serum catecholamines (namely dopamine [DA] and norepinephrine [NE]) associated with monocyte C–C chemokine receptor type 2 (CCR2) expression (p < 0.05), a receptor known to facilitate recruitment of monocytes towards arterial plaques. Additionally, NSD associated with catecholamine levels, especially DA in individuals of low SES. To further explore the potential role of NSD and the effects of catecholamines on monocytes, monocytes were treated in vitro with epinephrine [EPI], NE, or DA. Only DA increased CCR2 expression in a dose-dependent manner (p < 0.01), especially on non-classical monocytes (NCM). Furthermore, linear regression analysis between D2-like receptor surface expression and surface CCR2 expression suggested D2-like receptor signaling in NCM. Indicative of D2-signaling, cAMP levels were found to be lower in DA-treated monocytes compared to untreated controls (control 29.78 pmol/ml vs DA 22.97 pmol/ml; p = 0.038) and the impact of DA on NCM CCR2 expression was abrogated by co-treatment with 8-CPT, a cAMP analog. Furthermore, Filamin A (FLNA), a prominent actin-crosslinking protein, that is known to regulate CCR2 recycling, significantly decreased in DA-treated NCM (p < 0.05), indicating a reduction of CCR2 recycling. Overall, we provide a novel immunological mechanism, driven by DA signaling and CCR2, for how NSD may contribute to atherogenesis. Future studies should investigate the importance of DA in CVD development and progression in populations disproportionately experiencing chronic stress due to SDoH.

Telmisartan and losartan: The marked differences between their chemical and pharmacological properties may explain the difference in therapeutic efficacy in hospitalized patients with COVID‐19

Telmisartan and losartan: The marked differences between their chemical and pharmacological properties may explain the difference in therapeutic efficacy in hospitalized patients with COVID‐19

Experimental venous thrombus resolution is driven by IL-6 mediated monocyte actions

Deep venous thrombosis and residual thrombus burden correlates with circulating IL-6 levels in humans. To investigate the cellular source and role of IL-6 in thrombus resolution, Wild type C57BL/6J (WT), and IL-6−/− mice underwent induction of VT via inferior vena cava (IVC) stenosis or stasis. Vein wall (VW) and thrombus were analyzed by western blot, immunohistochemistry, and flow cytometry. Adoptive transfer of WT bone marrow derived monocytes was performed into IL6-/- mice to assess for rescue. Cultured BMDMs from WT and IL-6−/− mice underwent quantitative real time PCR and immunoblotting for fibrinolytic factors and matrix metalloproteinase activity. No differences in baseline coagulation function or platelet function were found between WT and IL-6−/− mice. VW and thrombus IL-6 and IL-6 leukocyte-specific receptor CD126 were elevated in a time-dependent fashion in both VT models. Ly6Clo Mo/MØ were the predominant leukocyte source of IL-6. IL-6−/− mice demonstrated larger, non-resolving stasis thrombi with less neovascularization, despite a similar number of monocytes/macrophages (Mo/MØ). Adoptive transfer of WT BMDM into IL-6−/− mice undergoing stasis VT resulted in phenotype rescue. Human specimens of endophlebectomized tissue showed co-staining of Monocyte and IL-6 receptor. Thrombosis matrix analysis revealed significantly increased thrombus fibronectin and collagen in IL-6−/− mice. MMP9 activity in vitro depended on endogenous IL-6 expression in Mo/MØ, and IL-6−/− mice exhibited stunted matrix metalloproteinase activity. Lack of IL-6 signaling impairs thrombus resolution potentially via dysregulation of MMP-9 leading to impaired thrombus recanalization and resolution. Restoring or augmenting monocyte-mediated IL-6 signaling in IL-6 deficient or normal subjects, respectively, may represent a non-anticoagulant target to improve thrombus resolution.

Influenza vaccination reveals sex dimorphic imprints of prior mild COVID-19.

Acute viral infections can have durable functional impacts on the immune system long after recovery, but how they affect homeostatic immune states and responses to future perturbations remain poorly understood1-4. Here we use systems immunology approaches, including longitudinal multimodal single-cell analysis (surface proteins, transcriptome and V(D)J sequences) to comparatively assess baseline immune statuses and responses to influenza vaccination in 33 healthy individuals after recovery from mild, non-hospitalized COVID-19 (mean, 151 days after diagnosis) and 40 age- and sex-matched control individuals who had never had COVID-19. At the baseline and independent of time after COVID-19, recoverees had elevated T cell activation signatures and lower expression of innate immune genesincluding Toll-like receptors in monocytes. Male individuals who had recovered from COVID-19 had coordinately higher innate, influenza-specific plasmablast, and antibody responses after vaccination compared with healthy male individuals and female individuals who had recovered from COVID-19, in part because male recoverees had monocytes with higher IL-15 responses early after vaccination coupled with elevated prevaccination frequencies of 'virtual memory'-like CD8+ T cells poised to produce more IFNγ after IL-15 stimulation. Moreover, the expression of the repressed innate immune genes in monocytes increased by day 1 to day 28 after vaccination in recoverees, therefore moving towards the prevaccination baseline of the healthy control individuals. By contrast, these genes decreased on day 1 and returned to the baseline by day 28 in the control individuals. Our study reveals sex-dimorphic effects of previous mild COVID-19 and suggests that viral infections in humans can establish new immunological set-points that affect future immune responses in an antigen-agnostic manner.

Novel peptide inhibitors targeting CD40 and CD40L interaction: A potential for atherosclerosis therapy

Atherosclerosis is a chronic inflammatory disease characterized by plaque build-up in the arteries, leading to the obstruction of blood flow. Macrophages are the primary immune cells found in the atherosclerotic lesions and are directly involved in atherosclerosis progression. Macrophages are derived from extravasating blood monocytes. The monocytic CD40 receptor is important for monocyte recruitment on the endothelium expressing the CD40 ligand (CD40L). Thus, targeting monocyte/macrophage interaction with the endothelium by inhibiting CD40-CD40L interaction may be a promising strategy for attenuating atherosclerosis. Monoclonal antibodies have been used against this target but shows various complications. We used an array of computer-aided drug discovery tools and molecular docking approaches to design a therapeutic inhibitory peptide that could efficiently bind to the critical residues (82Y, 84D, and 86N) on the CD40 receptor essential for the receptor's binding to CD40L. The initial screen identified a parent peptide with a high binding affinity to CD40, but the peptide exhibited a positive hepatotoxicity score. We then designed several novel peptidomimetic derivatives with higher binding affinities to CD40, good physicochemical properties, and negative hepatotoxicity as compared to the parent peptide. Furthermore, we conducted molecular dynamics simulations for both the apo and complexed forms of the receptor with ligand, and screened peptides to evaluate their stability. The designed peptidomimetic derivatives are promising therapeutics targeting the CD40-CD40L interaction and may potentially be used to attenuate atherosclerosis.

Identifying inflammatory phenotypes to target mechanism-specific treatments in sepsis

A clinical trial by Leventogiannis etal.1 suggests that ferritin and HLA-DR monocyte receptor expression can identify septic patients with macrophage-activation-like syndrome (MALS), or immunoparalysis, and that targeting IL-1ra treatment with this strategy may improve outcomes.

The relationship between TLR4/NF-κB/IL-1β signaling, cognitive impairment, and white-matter integrity in patients with stable chronic schizophrenia.

ObjectivePrevious studies have implicated intricate interactions between innate immunity and the brain in schizophrenia. Monocytic Toll-like receptor (TLR) 4 signaling, a crucial “sensor” of innate immunity, was reported to be over-activated in link with cognitive impairment in schizophrenia. As TLR4 is predominantly expressed on gliocytes prior to expression in neurons, we hypothesized that higher TLR4 levels may contribute to cognitive deterioration by affecting white matter microstructure.MethodsForty-four patients with stable chronic schizophrenia (SCS) and 59 healthy controls (HCs) were recruited in this study. The monocytic function was detected with lipopolysaccharide (LPS) stimulation to simulate bacterial infection. Basal and LPS- stimulated levels of TLR4, nuclear factor-kappa B (NF-κB), and interleukin (IL)-1β were quantified with flow cytometry. Cognitive function was assessed by the MATRICS Consensus Cognitive Battery (MCCB) and psychopathological symptoms were evaluated by the Positive and Negative Syndrome Scale (PANSS). We employed diffusion tensor imaging with a 3-T scanner and evaluated white-matter integrity with fractional anisotropy (FA). Subcortical volume and cortical thickness were also assessed.ResultsThe TLR4/NF-κB/IL-1β signaling pathway was activated in patients with SCS, but responded sluggishly to LPS stimulation when compared with HCs. Furthermore, monocytic TLR4 expressions were inversely correlated with cognitive function and white matter FA, but not with cortical thickness or subcortical gray matter volume in schizophrenia.ConclusionOur findings support altered TLR4 signaling pathway activity in association with deficits in cognition and white matter integrity in schizophrenia.

QiShenYiQi Pill Ameliorates Cardiac Fibrosis After Pressure Overload-Induced Cardiac Hypertrophy by Regulating FHL2 and the Macrophage RP S19/TGF-β1 Signaling Pathway.

Purpose: Heart failure (HF) is a leading cause of morbidity and mortality worldwide, and it is characterized by cardiac hypertrophy and fibrosis. However, effective treatments are not available to block cardiac fibrosis after cardiac hypertrophy. The QiShenYiQi pill (QSYQ) is an effective treatment for chronic HF. However, the underlying mechanism remains unclear. Methods: In the present study, a pressure overload-induced cardiac hypertrophy model was established in rats by inducing ascending aortic stenosis for 4 weeks. QSYQ was administered for 6 weeks, and its effects on cardiac fibrosis, myocardial apoptosis, RP S19 release, macrophage polarization, TGF-β1 production, and TGF-β1/Smad signaling were analyzed. In vitro studies using H9C2, Raw264.7, and RDF cell models were performed to confirm the in vivo study findings and evaluate the contribution to the observed effects of the main ingredients of QSYQ, namely, astragaloside IV, notoginsenoside R1, 3,4-dihydroxyl-phenyl lactic acid, and Dalbergia odorifera T. C. Chen oil. The role of four-and-a-half LIM domains protein 2 (FHL2) in cardiac fibrosis and QSYQ’s effects were assessed by small interfering RNAs (siRNAs). Results: QSYQ ameliorated cardiac fibrosis after pressure overload-induced cardiac hypertrophy and attenuated cardiomyocyte apoptosis, low FHL2 expression, and TGF-β1 release by the injured myocardium. QSYQ also inhibited the following: release of RP S19 from the injured myocardium, activation of C5a receptors in monocytes, polarization of macrophages, and release of TGF-β1. Moreover, QSYQ downregulated TGF-βR-II expression induced by TGF-β1 in fibroblasts and inhibited Smad protein activation and collagen release and deposition. Conclusion: The results showed that QSYQ inhibited myocardial fibrosis after pressure overload, which was mediated by RP S19-TGF-β1 signaling and decreased FHL2, thus providing support for QSYQ as a promising therapy for blocking myocardial fibrosis.

Opsonizing antibodies mediated SARS-CoV-2 entry into monocytes leads to inflammation.

Opsonizing antibodies mediated SARS-CoV-2 entry into monocytes leads to inflammation.

Cell-Crossing Functional Network Driven by microRNA-125a Regulates Endothelial Permeability and Monocyte Trafficking in Acute Inflammation

Opening of the endothelial barrier and targeted infiltration of leukocytes into the affected tissue are hallmarks of the inflammatory response. The molecular mechanisms regulating these processes are still widely elusive. In this study, we elucidate a novel regulatory network, in which miR-125a acts as a central hub that regulates and synchronizes both endothelial barrier permeability and monocyte migration. We found that inflammatory stimulation of endothelial cells induces miR-125a expression, which consecutively inhibits a regulatory network consisting of the two adhesion molecules VE-Cadherin (CDH5) and Claudin-5 (CLDN5), two regulatory tyrosine phosphatases (PTPN1, PPP1CA) and the transcription factor ETS1 eventually leading to the opening of the endothelial barrier. Moreover, under the influence of miR-125a, endothelial expression of the chemokine CCL2, the most predominant ligand for the monocytic chemokine receptor CCR2, was strongly enhanced. In monocytes, on the other hand, we detected markedly repressed expression levels of miR-125a upon inflammatory stimulation. This induced a forced expression of its direct target gene CCR2, entailing a strongly enhanced monocyte chemotaxis. Collectively, cell-type-specific differential expression of miR-125a forms a synergistic functional network controlling monocyte trafficking across the endothelial barrier towards the site of inflammation. In addition to the known mechanism of miRNAs being shuttled between cells via extracellular vesicles, our study uncovers a novel dimension of miRNA function: One miRNA, although disparately regulated in the cells involved, directs a biologic process in a synergistic and mutually reinforcing manner. These findings provide important new insights into the regulation of the inflammatory cascade and may be of great use for future clinical applications.

Dysfunctional monocytic toll-like receptor 4 signaling pathway and cognitive deficits in chronic schizophrenia patients with tardive dyskinesia

BackgroundMounting evidence suggests that the innate immune system is disrupted in schizophrenia patients with tardive dyskinesia (TD); however, the role of the toll-like receptor 4 (TLR4) signaling pathway remains unclear. MethodsIn this study, we quantified the expression of the monocytic TLR4 signaling pathway using flow cytometry, before and after lipopolysaccharide (LPS) stimulation, in chronic schizophrenia patients with (n = 61) and without TD (NTD, n = 61) and healthy controls (HCs, n = 74). Psychopathological symptoms, the severity of TD, and cognitive function were assessed using the Positive and Negative Syndrome Scale (PANSS), Abnormal Involuntary Movement Scale (AIMS), and MATRICS Consensus Cognitive Battery (MCCB), respectively. Results1) Both TD and NTD patients showed higher TLR4 signaling pathway activity at baseline than that in HCs, but their responses to LPS were weaker than those in HCs; 2) the alteration of the TLR4 signaling pathway was less severe in TD patients than in NTD patients; 3) TLR4 levels and MCCB scores were negatively correlated at baseline but positively correlated after LPS stimulation in TD patients; 4) there was no correlation between the TLR4 signals and PANSS or AIMS scores. ConclusionsOur findings suggested the TLR4 signaling pathway disturbance might be related to cognitive deficits in schizophrenia patients with TD.

The Neuropeptide VIP Limits Human Osteoclastogenesis: Clinical Associations with Bone Metabolism Markers in Patients with Early Arthritis.

We aimed to evaluate the direct action of VIP on crucial molecules involved in human osteoclast differentiation and function. We also investigated the relationship between VIP serum levels and bone remodeling mediators in early arthritis patients. The expression of VIP receptors and osteoclast gene markers in monocytes and in vitro differentiated osteoclasts was studied by real-time PCR. NFATc1 activity was measured using a TransAM® kit. Osteoclastogenesis was confirmed by quantification of tartrate-resistant acid phosphatase positive multinucleated cells. OsteoAssay® Surface Multiple Well Plate was used to evaluate bone-resorbing activity. The ring-shaped actin cytoskeleton and the VPAC1 and VPAC2 expression were analyzed by immunofluorescence. We described the presence of VIP receptors in monocytes and mature osteoclasts. Osteoclasts that formed in the presence of VIP showed a decreased expression of osteoclast differentiation gene markers and proteolytic enzymes involved in bone resorption. VIP reduced the resorption activity and decreased both β3 integrin expression and actin ring formation. Elevated serum VIP levels in early arthritis patients were associated with lower BMD loss and higher serum OPG concentration. These results demonstrate that VIP exerts an anti-osteoclastogenic action impairing both differentiation and resorption activity mainly through the negative regulation of NFATc1, evidencing its bone-protective effects in humans.

Deep Immune Profiling in Multiple Myeloma at Diagnosis and Under Lenalidomide Maintenance Therapy

IntroductionHere we report the results of one of the secondary endpoints of the Finnish Myeloma Group-MM02 study; composition of bone marrow (BM) immune cell subsets at treatment start and during lenalidomide (Len) maintenance focusing on 2 different response groups: good responders (GRs) and poor responders (PRs) at pre- and post-treatment stages. We evaluated the BM immune profile with CyTOF (cytometry by time-of-flight). Our hypothesis was that there would be distinct differences in immune cell profiles between patients with good and poor response, especially in the T and NK cell subsets.Patients and methodsTwenty-two patients were included in this CyTOF study. Eighteen were NDMM patients from FMG-MM02 study who received 3 RVD cycles followed by ASCT. Len started 3 months after ASCT 10 mg/day in 21/28-day cycles until progression or toxicity. BM samples were collected to the Finnish Hematology Registry Clinical Biobank (FHRB Biobank) at several timepoints; from 18 patients at diagnosis, from 11 patients 1 st sample at good response during Len and 2 nd sample if this good response was maintained and from 5 patients at relapse during Len. The patients in the good response cohort (n=11) had progression-free survival (PFS) > 5 years. For comparison, we included 4 BM samples from the FHRB Biobank, taken at a good response after ASCT from MM patients without exposure to Len.ResultsWith a median follow-up of 81 months (13-97) the median PFS was not reached in the good response (GR) cohort and was 18 months in the poor response (PR) cohort. The 1 st GR samples were collected after a median of 21 (6-46) months of Len. The 2 nd samples in GR cohort were collected after a median of 56 (45-67) months of Len. The PR samples were taken after a median of 6 (2-23) months of Len.CyTOF analysis revealed distinct good and poor responder's immune signatures at baseline level. GR, baseline group has shifted phenotype of T cells toward the CD8 T cells, expressing markers, attributed to the cytotoxicity (CD45RA, CD57), as well as having slightly higher abundance of CD8 TE and lower abundance of CD8 naïve T cells. Total T cells amounts were significantly higher in GR. Increased expression of CD56, CD57, and CD16 were also seen on NK cells in GR at the baseline, indicating both maturation and cytotoxic potential of NKs. In contrast, a significant decrease of CD56 and CD16 expression suggesting reduced cytotoxic potential and increase of CD57 were seen on NKs in PR, baseline indicating senescence status a phenotype associated with exhaustion.By using viSNE we discovered two novel populations - MAC1, and MAC2, - associated with disease pathogenesis. We further investigated the composition of these populations, and it appears that MAC1 expressed CD38+CD56+CD45-CD19- presumably malignant plasma cells and MAC2 expressed CD45- CD14+CD38+CD56+TCRgd+CCR7+CCR6+CXCR4+ CXCR3+CXCR5+CD294+, which might be the novel populations, having the features of myeloid suppressor cells. These two immune cells were higher in PR (9.2% and 8.2%, respectively) at baseline as compared to the GR (2.3% and 1.7%).NKs, T cells, and B cells showed a high expression of monocytic marker CD14 and chemokine receptors (CCR7, CCR6, CXCR4, CXCR3, and CXCR5) in PR both at baseline and relapse. This might be attributed to either biological features of MM environment, or the high level of interaction between these populations and monocytes, which left traces of their membranes on the non-monocytic populations.ConclusionsPatients, responded to the treatment, have higher abundances of effector/cytotoxic cells, expressing higher levels of CD57 and/or CD45RA for T cells, and CD57, CD16, and CD56 for NK cells indicating proper differentiation and maturation of T, and NK cells to effector and cytotoxic subsets. Additionally, those patients have less degree of tumor burden as well as decreased expression of chemokine receptors. During the therapy administration, good responders show the increase in effector memory CD4 and CD8 subsets of T cells abundance, indicating even the higher cytotoxic effect of immune system. DisclosuresSilvennoinen: Amgen: Consultancy, Honoraria, Research Funding; Celgene/BMS: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Research Funding. Luoma: Amgen: Honoraria; Janssen: Honoraria; Incyte: Honoraria. Anttila: Amgen: Honoraria; Celgene: Honoraria; Janssen: Honoraria; Takeda: Honoraria. Säily: Takeda: Honoraria; Janssen: Honoraria; Sanofi: Honoraria; Celgene: Honoraria. Partanen: Takeda: Honoraria; Abbvie: Honoraria; Behring: Honoraria. Heckman: Novartis: Research Funding; Orion Pharma: Research Funding; Celgene/BMS: Research Funding; Oncopeptides: Consultancy, Research Funding; Kronos Bio, Inc.: Research Funding.