TNF-α Production Research Articles

Intraperitoneal Administration of S100A8 Ameliorates Experimental Acute Colitis in Rats

S100A8 is a protein that is abundant in neutrophils and macrophages (MΦ), but its role in inflammation remains unclear. This study aimed to assess the immunological role(s) of S100A8 in acute intestinal inflammation in rats and its role in MΦ. Rat recombinant S100A8 (rr-S100A8, 1.0 mg/kg) was intraperitoneally administered daily to rats with 3% dextran sulfate sodium (DSS) (DSS + A8 group)-induced experimental acute colitis. The histological severity score (6.50 ± 0.51, p = 0.038) in the DSS + A8 group rats remained lower than that (9.75 ± 1.48) of the rats without S100A8 (DSS group) administration. The tumor necrosis factor-alpha (TNF-α) production in the colon tissues of the rats in the DSS + A8 group (4.76 ± 0.90 pg/mL/g, p = 0.042) was significantly suppressed, compared with that of the DSS group (10.45 ± 2.04 pg/mL/g). To stimulate rat peritoneal MΦ, rr-S100A8, the anti-rat S100A8 antibody, and a lipopolysaccharide (LPS) were used in the in vitro experiments. In the MΦ stimulated with rr-S100A8 for 2 h, the mRNA level of intracellular S100A8 (47.41 ± 24.44, p = 0.002) increased in an autocrine manner, whereas that of S100A9 (0.24 ± 0.43, p = 0.782) was not significant. The TNF-α mRNA level in the MΦ treated with LPS and the anti-rat S100A8 antibody significantly increased (102.26 ± 18.60, p = 0.001) compared to that with LPS alone (16.9 ± 8.56). These results indicate that S100A8 can serve as an anti-inflammatory protein in acute inflammation by negatively regulating S100A9 and TNF-α production through inflammatory signaling pathways in MΦ.

Loss of O6-methylguanine DNA methyltransferase (MGMT) in macrophages alters responses to TLR3 stimulation and enhances DNA double-strand breaks and mitophagy.

O6-methylguanine-DNA methyltransferase (MGMT) is a DNA damage repair enzyme. The roles of this enzyme in immune cells remain unclear. In this study, we explored the roles of MGMT in bone marrow-derived murine macrophages (BMMs) via the use of MGMT knockout (KO) mice. Loss of MGMT altered the response to TLR3 agonists (poly (I:C)), such as dampening the production of TNFα and IL-6. Increased DNA double-strand breaks (DSBs) were observed in MGMT-KO macrophages but did not result in increased cell death. MGMT localized to both nuclei and mitochondria at increasing levels during poly (I:C) stimulation. MGMT deficiency increased the production of mitochondrial reactive oxygen species (mtROS), which was correlated with increased mitophagy. The underlying mechanism involves mediation through activation of the AMPKα pathway. Taken together, our findings reveal the roles of MGMT in macrophages in regulating the response to TLR3, which links DSBs to mtROS and mitophagy via the AMPKα pathway. These roles may have consequences for the inflammatory response and chronic inflammation.

Anti-aging potential of Cephalotaxus harringtonia extracts: the role of harringtonine and homoharringtonine in skin protection

Photoaging damages the skin layers. The tumor necrosis factor-alpha (TNF-α) plays a crucial role in the central mechanism of photoaging. TNF-α production leads to direct damage to skin cells and facilitates the degradation of vital extracellular matrix (ECM) proteins. TNF-α stimulates matrix metalloproteinase-1 (MMP-1) activation This accelerates the loss of skin elasticity and wrinkle formation. Thus, preventing photoaging and delaying the skin aging process are important research objectives, and the development of new anti-aging substances that target the TNF-α and MMP-1 pathways is promising. In this context, the efficacies of four extracts derived from two types of Cephalotaxus harringtonia (CH) buds (CH-10Y-buds, CH-200Y-buds) and leaves (CH-10Y-leaves, CH-200Y-leaves) were investigated, exhibiting a significant reduction in reactive oxygen species (ROS). Among the four extracts, CH-10Y-buds was the most effective in reducing ROS and exhibited the highest amounts of harringtonine and homoharringtonine. The activities of harringtonine, homoharringtonine, and ginkgetin were evaluated; harringtonine exhibited a high efficacy in inhibiting TNF-α-induced inflammatory responses and MMP-1 activation, thereby reducing collagen degradation. These findings suggest that CH-10Y-buds and their components herringtonin are promising candidates for preventing damage caused by photoaging. Our results can facilitate the development of new methods for maintaining skin health and inhibiting the skin aging process. Further research is necessary to comprehensively evaluate the potential efficacy of these candidate substances and investigate their applicability to actual skin. Such studies will aid in the development of more effective anti-aging strategies in the future.

IP-10 acts early in CV-A16 infection to induce BBB destruction and promote virus entry into the CNS by increasing TNF-α expression

The mechanisms underlying pathological changes in the central nervous system (CNS) following Coxsackievirus A16 (CV-A16) infection have not yet been elucidated. IFN-γ-inducible protein-10 (IP-10) is often used as a predictive factor to monitor early virus infection. It has also been reported that IP-10 plays a pivotal role in neuroinflammation. In this study, we aimed to explore the role of IP-10 in the neuropathogenesis of CV-A16 infection. We observed that the level of IP-10, as well as the TLR3-TRIF-TRAF3-TBK1-NF-κB and RIG-I/MDA5-MAVS-TRAFS-TBK1-NF-κB pathways, which are the upstream of IP-10, were significantly elevated during the course of CV-A16 infection. This increase was accompanied by an increase in a series of inflammatory cytokines at different time-points during CV-A16 infection. To determine whether IP-10 influences BBB integrity, we examined junctional complexes. Our results revealed that the expression levels of Claudin5, Occludin, ZO-1 and VE-Cadherin were notably decreased in CV-A16-infected HUVECs, but these indicators were restored in CV-A16-infected HUVECs with Eldelumab treatment. Nevertheless, IP-10 is only a chemokine that primarily traffics CXCR3-positive immune cells to inflammatory sites or promotes the production of inflammatory cytokines. Therefore, the interactions between IP-10 and inflammatory cytokines were evaluated. Our data revealed that IP-10 mediated the production of TNF-α, which was also observed to change the junctional complexes. Moreover, in a suckling mouse model, IP-10 and TNF-α treatments exacerbated clinical symptoms, mortality and pathological changes in the brain of CV-A16-infected mice, but Anti-IP-10 and Anti-TNF-α treatments alleviated these changes. Our data also revealed that IP-10 may be detected early in CV-A16 infection, whereas TNF-α was detected late in CV-A16 infection, and the production of TNF-α was also found to be positively correlated with IP-10. In addition, IP-10 and TNF-α were observed to reduce junctional complexes and enhance virus entry into the CNS. Taken together, this study provides the first evidence that CV-A16 activates the IP-10/TNF-α regulatory axis to cause BBB damage and accelerate the formation of neuroinflammation in infected hosts, which not only provides a new understanding of the neuropathogenesis caused by CV-A16, but also offers a promising target for the development of CV-A16 antiviral drugs.

Resveratrol Potentiates BCG-induced Trained Immunity in Human Monocytes.

Resveratrol is a natural polyphenol derived from plants such as grapes and berries. In addition to its role in plants during injury and infection, various cardioprotective, neuroprotective, and longevity-promoting effects were reported in diverse model organisms. The primary target of resveratrol is the deacetylase Sirtuin 1 (SIRT1), which regulates many immunological processes, including BCG-induced trained immunity response in humans. We, therefore, investigated the effect of resveratrol on trained immunity induced by BCG, β-glucan, C. albicans, or oxidized low-density lipoprotein (oxLDL). Using an in-vitro model of trained immunity with monocytes obtained from healthy donors, we demonstrate that resveratrol amplifies BCG-induced trained immunity regarding IL-6 and TNFα production after a secondary challenge. Although resveratrol did not improve and even limited glycolysis, oxidative phosphorylation, and reactive oxygen species production, it enhanced the permissive epigenetic mark H3K27Ac on IL-6 and TNFα promoters. In contrast to BCG-induced trained immunity, resveratrol potently inhibited training induced by β-glucan, C. albicans, oxLDL, and muramyl dipeptide (MDP), a peptidoglycan component of BCG. Resveratrol's unique boosting effect on BCG training depended on BCG being alive and metabolically active. These results suggest that resveratrol might amplify the effects of BCG vaccination, which should be mechanistically characterized further. In addition, resveratrol could alleviate oxLDL-induced training of innate immune cells in atherosclerosis, and in-vivo studies of trained immunity combined with resveratrol are warranted to explore these therapeutic possibilities.

Comprehensive In silico and In vitro evaluation of Plectranthus amboinicus essential oil: A promising inhibitor of SARS-CoV-2 B.1.1.529 Omicron variant, proinflammatory biomarkers and diabetes-related enzymes

Existing challenges, such as the viral SARS-CoV-2 B.1.1.529 Omicron variants, adverse reactions, and limited availability of drugs for COVID-19 continue to challenge global health. Severe inflammatory response associated with COVID-19 has been shown to worsen diabetic conditions and finding a range of treatment options for COVID-19 is significant. The research investigated the potential of Plectranthus amboinicus (Lour.) Spreng. (Lamiaceae) essential oil (PEO), known for its bioactive terpene content, as a multifaceted therapeutic agent. In silico and in vitro approaches were conducted to evaluate its inhibitory effects on the replication of Omicron variant, its ability to modulate proinflammatory biomarkers, and its impact on diabetes-related enzymes. PEO was extracted by hydrodistillation method. GC-MS analysis revealed 62 compounds. In silico molecular docking showed that the top ten PEO major components exhibited strong binding affinities with Omicron 3CL protease (-4.0 to −6.1 kcal/mol) and spike-RBD protein (-6.1 to −9.2 kcal/mol). PEO (6.25–200 μg mL⁻¹) significantly inhibited the B.1.1.529 Omicron SARS-CoV-2 3CL protease and Spike-RBD. PEO showed a cytotoxic effect at >80 μg mL⁻¹ in LPS-induced macrophage and inhibited production of TNF-α from 6.25 to 50 μg mL⁻¹, indicating its potential to mitigate the cytokine storm in link with severe COVID-19 cases. In vitro, PEO at 6.25–200 μg mL⁻¹ significantly inhibited α-amylase and α-glucosidase enzymes, suggesting that PEO components could modulate key enzymes involved in glucose metabolisms. These findings showed the potential of PEO as an antiviral, anti-inflammatory, and antidiabetic agent and offer an opportunity to further clinical investigations in testing the efficacy as an alternative approach to managing COVID-19 and its complications.

Assessing sepsis-induced immunosuppression to predict positive blood cultures

IntroductionBacteremia is a life-threatening condition that can progress to sepsis and septic shock, leading to significant mortality in the emergency department (ED). The standard diagnostic method, blood culture, is time-consuming and prone to false positives and false negatives. Although not widely accepted, several clinical and artificial intelligence-based algorithms have been recently developed to predict bacteremia. However, these strategies require further identification of new variables to improve their diagnostic accuracy. This study proposes a novel strategy to predict positive blood cultures by assessing sepsis-induced immunosuppression status through endotoxin tolerance assessment.MethodsOptimal assay conditions have been explored and tested in sepsis-suspected patients meeting the Sepsis-3 criteria. Blood samples were collected at ED admission, and endotoxin (lipopolysaccharide, LPS) challenge was performed to evaluate the innate immune response through cytokine profiling.ResultsClinical variables, immune cell population biomarkers, and cytokine levels (tumor necrosis factor [TNFα], IL-1β, IL-6, IL-8, and IL-10) were measured. Patients with positive blood cultures exhibited significantly lower TNFα production after LPS challenge than did those with negative blood cultures. The study also included a validation cohort to confirm that the response was consistent.DiscussionThe results of this study highlight the innate immune system immunosuppression state as a critical parameter for sepsis diagnosis. Notably, the present study identified a reduction in monocyte populations and specific cytokine profiles as potential predictive markers. This study showed that the LPS challenge can be used to effectively distinguish between patients with bloodstream infection leading to sepsis and those whose blood cultures are negative, providinga rapid and reliable diagnostic tool to predict positive blood cultures. The potential applicability of these findings could enhance clinical practice in terms of the accuracy and promptness of sepsis diagnosis in the ED, improving patient outcomes through timely and appropriate treatment.

Design, Synthesis, Anti-inflammatory Evaluation and In silico Molecular Docking of Novel Furan-based Derivatives as Potential TNF-α Production Inhibitors

Introduction: Inflammation is the first response and an alarming signal for the onset of chronic disease. Most of the anti-inflammatory drugs available in the market are reported to have undesirable gastrointestinal toxicities. Therefore, it is of urgent significance to develop anti-inflammatory drugs with low toxicity and good efficacy. Methods: We created a targeted scaffold based on a literature review by combining the different structural characteristics of furan and benzyl amides into a single pharmacophore. A series of eighteen furanbased derivatives (1-18) were designed, synthesized for in vitro and in vivo anti-inflammatory activity. The characterization of synthesized compounds was elucidated by techniques like 1H-NMR, 13C-NMR, FT-IR and MS. Results: The synthetic compounds were examined through molecular docking studies on TNF-α for probable binding mode and interactions with hydrophilic and hydrophobic pocket of TNF-α in comparison to standard drug (Indomethacin). Conclusion: When compared to the standard treatment, compounds 18, 15 and 9 displayed a remarkable inhibitory effect on the production of TNF-α and in vivo inflammatory activity with no damage to stomach and reduction of LPO. The compounds 18, 15 and 9 might be a good consideration for potential antiinflammatory agents.

Network pharmacology and experimental verification unraveled the mechanism of Bailing Capsule against asthma.

Asthma is a serious public health challenge around the world. Recent studies into traditional Chinese medicine preparations for asthma have yielded promising findings regarding Bailing Capsule's potential in bronchial asthma prevention and treatment. This study aims to initially clarify the potential mechanism of Bailing Capsule in the treatment of asthma using network pharmacology and in vitro experimental approaches. Network pharmacology was adopted to detect the active ingredients of Bailing Capsule via Traditional Chinese Medicine Systems Pharmacology Database, and the key targets and signaling pathways in the treatment of asthma were predicted. Docking and molecular dynamics simulations were conducted to verify the most important interactions formed by these probes within different regions of the binding site. The predicted targets were validated in lipopolysaccharide-induced 16HBE cell experiment. Seven active ingredients were screened from Bailing Capsule, 294 overlapping targets matched with asthma were considered potential therapeutic targets, such as SRC, TP53, STAT3, and E1A binding protein P300. The main functional pathways involving these key targets include phosphatidylinositol 3-kinase/protein kinase B, mitogen-activated protein kinase, renin-angiotensin system and other signaling pathways, which were mainly involved in the inflammatory response, apoptosis, and xenobiotic stimulus. Moreover, molecular docking showed that Cerevisterol have higher affinity for SRC, TP53, STAT3, and E1A binding protein P300 than other main active components, which is close to the docking results of the co-crystallized ligands to proteins. Consequently, Cerevisterol was selected for molecular dynamics simulation and the results show that Cerevisterol can bind most tightly to SRC, TP53, and STAT3. Bailing Capsule can promote the growth of 16HBE cell, reduce the production of IL-4, TNF-α and IL-6, and down-regulate the levels of SRC and STAT3 mRNA. This study preliminarily reveals the potential mechanism of Bailing Capsule against asthma with the aid of network pharmacology and in vitro cell experiment, which provided reference and guidance for in-depth research and clinical application.

Persistence of activated anti-mesothelin hYP218 chimeric antigen receptor T cells in the tumour is associated with efficacy in gastric and colorectal carcinomas.

Patients with advanced gastric and colorectal cancers have limited treatment options. Since mesothelin is highly expressed in these tumour types, we evaluated the therapeutic benefits of anti-mesothelin hYP218 CAR T cells alone, and in combination with anti-PD1 antibody, pembrolizumab. GEPIA analysis was performed using human gastric (n=408) and colon cancer tumours (n=275) in TCGA database, to evaluate mRNA expression of mesothelin, compared to normal tissues. Mesothelin expression in gastric and colorectal cancer cell-lines (n=5) was analysed using flow cytometry. In vitro efficacy by hYP218 CAR T cells was tested by cytotoxicity and cytokine release assays. In vivo anti-tumour efficacy of hYP218 CAR T cells alone, and in combination with pembrolizumab, was evaluated in NSG mice bearing human gastric (HGC27) and colorectal (SW48) tumour xenografts. Additionally, hYP218 CAR-T cell persistence, activation and exhaustion marker-expression were studied. Mesothelin expression was significantly higher in gastric and colon cancer biopsies compared to normal tissues (p<.005). Mesothelin expression in gastric and colon cancer cell lines ranged from 10000 to 70000 molecules per cell. hYP218 CAR T cells demonstrated strong cytotoxic activity at low effector to target ratio, ranging from 0.24 to 1.0. In NSG mouse-models, hYP218 CAR T cells demonstrated anti-tumour efficacy and persisted in the tumour microenvironment in a functional state at day 40 posttreatment with expression of activation markers CD39 and CD69, increased production of IFN-γ and TNF-α and ability to kill tumour cells in vitro when isolated from tumours. There was increased PD1 expression. In combination with pembrolizumab, hYP218 CAR T cells led to slower tumour growth in NSG mice bearing large but not small HGC27 tumours. Anti-tumour efficacy of hYP218 CAR T cells is due to increased accumulation of activated CAR T cells in the tumour and combination with pembrolizumab resulted in improvement in anti-tumour activity of large established tumours. HIGHLIGHTS: Mesothelin expression is significantly higher in gastric and colorectal cancers than normal tissues. hYP218 CAR T cells demonstrate strong anti-tumour activity against mesothelin-positive gastric and colorectal carcinomas. Activated hYP218 CAR T cells persist in the tumour microenvironment and retain their cytotoxic activity. Addition of pembrolizumab in larger tumours enhance CAR T cell efficacy.

Long-term monocyte activation after coronary artery bypass grafting: an exploratory prospective observational study

Major surgery such as coronary artery bypass grafting (CABG) is associated with an increased post-operative risk of atherosclerotic cardiovascular events. Cells of the innate immune system can adopt a long-lasting pro-inflammatory and atherogenic phenotype after brief exposure to exogenous or endogenous inflammatory stimuli, a process called “trained immunity”. We hypothesized that the surgery-induced inflammation leads to sustained alterations in monocyte function, which promote the subsequent occurrence of cardiovascular events. Blood from 13 patients undergoing elective CABG was obtained before, 3-7 days (median 4) after, and 6-8 weeks (median 6) weeks after surgery. At 3-7 days postoperatively, circulating C-reactive protein (CRP) concentration, leukocyte counts and ex vivo Peripheral Blood Mononuclear Cell (PBMC) IL-6, TNFα and IL-1Ra production after stimulation (with various inflammatory stimuli) were significantly increased. Simultaneously, there was a reduction in monocyte HLA-DR expression. 6-8 weeks after CABG there was an ongoing systemic pro-inflammatory state with higher CRP concentrations, increased stimulated ex vivo PBMC IL-6 production, changes in monocytes subsets, and a higher expression of CCR2 on monocytes compared to baseline. In conclusion, CABG induces a persistent systemic inflammatory reaction with a sustained activated monocyte phenotype. This might contribute to the increased atherosclerotic cardiovascular event risk observed in cardiac surgery patients.

Cefiderocol has immunoregulative effects in LPS-induced vitro experimental model via inhibiting inflammation and ferroptosis

BackgroundCefiderocol is a new catecholamine-containing siderophore cephalosporin. It, however, remains unclear how cefiderocol modulates the immune response of the host. ObjectivesThis study elucidated whether cefiderocol exerts immunoprotective effects in an in vitro experimental model induced with lipopolysaccharide (LPS). MethodsMouse macrophage RAW 264.7 cells were exposed to LPS (100 ng/mL) or LPS + cefiderocol (40 mg/L) to assess the immunomodulatory effect of cefiderocol in vitro. ELISA was performed on cell culture supernatants to estimate cytokine levels. Ferroptosis level was also quantified by detecting intracellular reactive oxygen species (ROS) and iron levels through flow cytometry analysis. Malondialdehyde (MDA) and glutathione (GSH) levels were estimated by ELISA. We conducted western blotting assay for evaluating key ferroptosis pathway proteins. ResultsCefiderocol alleviated LPS-induced inflammation by reducing IL-6, TNF-α, and IL-1β production levels and enhancing the IL-10 production level. Further analysis to determine the underlying mechanism revealed that cefiderocol inhibited ferroptosis; this was confirmed by reduced ROS, MDA, and Fe2+ ion levels; increased GSH levels; upregulated expression of solute carrier family 7 member 11, glutathione peroxidase 4, nuclear factor erythroid 2-related factor 2, and ferroptosis suppressor protein 1; and downregulated expression of acyl-CoA synthetase long-chain family member 4. ConclusionsCefiderocol may play a key role in reducing inflammation by decreasing inflammatory cytokine release and suppressing ferroptosis.

Interleukin-12 decorated nanosized semiflexible Immunofilaments enable directed targeting and augmented IFNγ responses of Natural Killer Cells

Immunotherapies are a powerful strategy to treat cancer by modulating the immune system to raise an anti-tumor immune response. A prime example of immunotherapies are cytokines - small immunomodulatory molecules that are widely used to stimulate immune cells. Undirected administration of cytokines, however, can cause severe side effects, preventing the use of potent cytokines, such as Interleukin (IL)-12, which induces IFNγ responses by cytotoxic effector lymphocytes, including NK cells. Biomaterials, like nanoparticles, can encapsulate IL-12 and accumulate at the tumor site to alleviate side effects. Yet, the released IL-12 might not be directly targeted to extracellular IL-12 receptors on the specific effector cells, thereby potentially compromising the cytokine's therapeutic efficacy. Here, we develop a polymer-based platform to target NK cells, which we call immunofilaments. Immunofilaments are nanosized linear polymers that present an anti-CD16 antibody and IL-12 effectively to NK cells and lead to synergistic NK cell activation as highlighted by an increase in TNFα and IFNγ production and upregulation of multiple activation markers, including CD25, CD69, and degranulation marker CD107a. NK cell proliferation is enhanced in the presence of both anti-CD16 antibody and IL-12 compared to giving IL-12 separately. Finally, we demonstrate that the IF platform is suitable for in vivo applications, as immunofilaments readily activate human NK cells upon administration to mice. STATEMENT OF SIGNIFICANCE: IL-12 is a potent cytokine that stimulates IFNγ responses in NK cells, which supports an anti-tumor immune response. Due to its high potency, the delivery of IL-12 needs to be highly controlled to prevent severe adverse side effects, which can be achieved by using biomaterials. This study shows that nanosized polymers termed Immunofilaments can be used to immobilize IL-12 and effectively target and activate NK cells by co-conjugation of anti-CD16 antibodies. This work is a prime example of careful engineering of innovative biomaterials to improve immunotherapy.

Anti-Inflammatory Activity of Biotransformed Platycodon grandiflorum Root Extracts Containing 3-O-β-D-Glucopyranosyl Platycosides in LPS-Stimulated Alveolar Macrophages, NR8383 Cells.

Acute lung injury (ALI) is a severe inflammatory condition characterized by excessive immune responses and oxidative stress, leading to significant tissue damage. Given the need for novel therapeutic agents, this study aimed to explore the anti-inflammatory activity and mechanisms of biotransformed Platycodon grandiflorum root extracts (BT-PGR), which were enzymatically processed using rapidsase PL Classic from Aspergillus niger. The goal was to assess the potential of BT-PGR as a natural treatment for ALI. BT-PGR effectively inhibited the production of NO, iNOS, IL-1β, IL-6, and TNF-α induced by LPS in NR8383 cells. BT-PGR inhibited the phosphorylation of ERK1/2, p38, JNK and p65 in LPS-stimulated NR8383 cells. In addition, BT-PGR suppressed LPS-mediated activation of NFκB luciferase activity. BT-PGR increased the levels of HO-1 and the inhibition of HO-1 by ZnPP attenuated BT-PGR-mediated inhibition of NO production. In addition, the inhibition of PI3K by LY294002 blocked the BT-PGR-mediated increase of HO-1 level. BT-PGR increased nuclear Nrf2 level and the knockdown of Nrf2 by siRNA inhibited BT-PGR-mediated increase of HO-1 level. In addition, inhibition of PI3K by LY294002 suppressed the increase of nuclear Nrf2 level. Based on these results, it can be inferred that BT-PGR exhibits anti-inflammatory activity in rat alveolar macrophages, suggesting its potential as a natural candidate for the improvement of ALI.

In Vitro Anti-inflammatory Effect of Secretome from Umbilical Cord-derived Mesenchymal Stem Cells in COVID-19 Patient Blood: A Study on sIL-6R, sgp130, IL-1RA and Anti/pro Inflammatory Cytokines

COVID-19 exhibits a wide range of clinical manifestations which severity of the disease is linked to uncontrolled escalation of inflammatory mediators. Ongoing research has identified the immunomodulatory effects of the MSC-derived secretome as a potential therapy for COVID-19. However, the precise mechanism by which the secretome exerts its therapeutic effect on COVID-19 remains unclear. This study aims to investigate whether the components of the UC-MSC-derived secretome can alter the inflammatory characteristics of immune cells. To achieve this, an in vitro study will be conducted involving co-incubation of whole blood with secretomes, followed by LPS stimulation. A total of 12 blood samples from severe COVID-19 and healthy subjects were cultured into three groups (RPMI control, 3μl and 9μl secretome group) incubated for 24 hours. Then, the cultures were exposed to LPS for 48 hours. The levels of sIL-6R, sgp130, IL-1RA, IL-6, TNF-α, IFN-γ, and IL-10 were measured. Results showed that LPS increased IL-6, TNF-α, and IL-10 production, while reducing sIL-6R, and sgp130, but no changes seen in IFN-γ in secretome-incubated blood cultures. The post-LPS/pre-LPS ratio analysis was conducted to investigate the anti-inflammatory potential of secretome. It was found that the secretome provides its anti-inflammatory effects through the role of IL-1RA.

Co-delivery of Interferon Regulatory Factor 5 (IRF5) siRNA and dasatinib by a disulfide bond bearing polymeric carrier for enhanced anti-inflammatory effects

Co-delivery of chemical drugs and nucleic acids has attracted a great interest recently for treatment of inflammatory diseases. Dasatinib (DB), a tyrosine kinase inhibitor with anti-cancer effects, and Interferon Regulatory Factor 5 (IRF5) siRNA have shown anti-inflammatory effects. In the present study, a novel redox-responsive polymeric micelle was designed for co-delivery of DB and IRF5 siRNA-expressing plasmid (psiRF5) to enhance anti-inflammatory effects on macrophages. psiRF5 was condensed efficiently to redox-responsive micelles of DB-conjugated chitosan (CN) composed of disulfide bond, from different molecular weights of CN to form CN-SS-DB/psiRF5 micelles. The micelles with optimum N/P ratios had particle sizes of 287.8 and 245.4 nm and positive zeta potentials. The disulfide bond bearing micelles showed a redox-responsive drug release, protected the plasmid from being dissociated or degraded in exposure with heparin, serum and DNase I, and significantly enhanced the transfection efficiency and IRF5-gene silencing compared to naked psiRF5. The optimum micelles exhibited a dramatic reduction in IRF5 expression and revealed a notably higher anti-inflammatory effect than either DB or psiRF5, as indicated by more IL-10 and less IL-6 and TNF-α production by LPS-stimulated RAW264.7 macrophages incubated with the co-delivery system. The resultant nanocarriers might be promising for more effective treatment of inflammatory diseases.

Antitumoral Activity and Metabolic Signatures of Dichloroacetate, 6-Aminonicotinamide and Etomoxir in Breast-Tumor-Educated Macrophages.

Pharmacological targeting of metabolic pathways represents an appealing strategy to selectively kill cancer cells while promoting antitumor functions of stromal cells. In this study, we assessed the effectiveness of 13 metabolic drugs (MDs) in steering in vitro generated breast tumor-educated macrophages (TEMs) toward an antitumoral phenotype. For that, the production of vascular endothelial growth factor (VEGF) and tumor necrosis factor α (TNF-α), two important regulators of tumor progression, was evaluated. Notably, dichloroacetate (DCA), 6-aminonicotinamide (6-AN), and etomoxir decreased VEGF production and enhanced TNF-α release. Hence, we further clarified their impact on TEM metabolism using an untargeted NMR-based metabolomics approach. DCA downregulated glycolysis and enhanced the utilization of extracellular substrates like lactate while reconfiguring lipid metabolism. Several DCA-induced changes significantly correlated with heightened TNF-α production in response to pro-inflammatory stimulation. The inhibition of the pentose phosphate pathway by 6-AN was accompanied by enhanced glutaminolysis, which correlated with a decreased level of VEGF production. In etomoxir-treated TEM, inhibition of fatty acid oxidation was compensated through upregulation of glycolysis, catabolism of intracellular amino acids, and consumption of extracellular branched chain alpha-ketoacids (BCKA) and citrate. Overall, our results offer a comprehensive view of the metabolic signature of each MD in breast TEM and highlight putative correlations with phenotypic effects.

HIV-1 latency reversal agent boosting is not limited by opioid use.

Opioid use may impact the HIV-1 reservoir and its reversal from latency. We studied forty-seven virally suppressed people with HIV (PWH) and observed that lower concentration of HIV-1 latency reversal agents (LRA), used in combination with small molecules that did not reverse latency, synergistically increased the magnitude of HIV-1 re-activation ex vivo, regardless of opioid use. This LRA boosting, which combined a Smac mimetic or low-dose protein kinase C agonist with histone deacetylase inhibitors, generated significantly more unspliced HIV-1 transcription than phorbol 12-myristate 13-acetate (PMA) with ionomycin (PMAi), the maximal known HIV-1 reactivator. LRA boosting associated with greater histone acetylation, modulated surface activation-induced markers, and altered T cell production of TNFα, IL-2, and IFNγ. HIV-1 reservoirs in PWH contained unspliced and polyadenylated (polyA) virus mRNA, the ratios of which were greater in resting than total CD4+ T cells and correct to 1:1 with PMAi exposure. We characterized treated suppressed HIV-1 infection as a period of inefficient, not absent, virus transcription. Multiply spliced HIV-1 transcripts and virion production did not consistently increase with LRA boosting, suggesting the presence of a persistent post-transcriptional block. LRA boosting can be leveraged to probe mechanisms of an effective cellular HIV-1 latency reversal program.

Selenopolysaccharide Isolated from Lentinula edodes Mycelium Affects Human T-Cell Function.

Lentinula edodes polysaccharides are natural immunomodulators. SeLe30, analyzed in this study, is a new mixture of selenium-enriched linear 1,4-α-glucans and 1,3-β- and 1,6-β-glucans isolated from L. edodes mycelium. In the present study, we evaluated its immunomodulatory properties in human T cells. Peripheral blood mononuclear cells (PBMCs) and T cells were isolated from healthy donors' buffy coats. The effects of SeLe30 on CD25, CD366, and CD279 expression, the subsets of CD8+ T cells, and IFN-γ, IL-6, and TNF-α production were analyzed. SeLe30 downregulated CD25, CD279, and CD366 expression on T cells stimulated by the anti-CD3 antibody (Ab) and upregulated in unstimulated and anti-CD3/CD28-Abs-stimulated T cells. It increased the percentage of central memory CD8+ T cells in unstimulated PBMCs and naïve and central memory T cells in anti-CD3-Ab-stimulated PBMCs. SeLe30 decreased the number of central memory and naïve CD8+ T cells in anti-CD3/CD28-stimulated T cells, whereas, in PBMCs, it reduced the percentage of effector memory CD8+ T cells. Moreover, SeLe30 upregulated cytokine production. SeLe30 exhibits context-dependent effects on T cells. It acts on unstimulated T cells, affecting their activation while increasing the expression of immune checkpoints, which sensitizes them to inhibitory signals that can silence this activation. In the case of a lack of costimulation, SeLe30 exhibits an inhibitory effect, reducing T-cell activation. In cells stimulated by dual signals, its effect is further enhanced, again increasing the "safety brake" of CD366 and CD279. However, the final SeLe30 effect is mediated by its indirect impacts by altering interactions with other immune cells.

Interleukin-6 levels in atrium and onset of spontaneous atrial fibrillation: is there a causal relationship

Abstract Background Cumulative evidence suggests that atrial interleukin-6 (IL-6) may play a significant role in the development of spontaneous postoperative atrial fibrillation (sPOAF) in coronary artery bypass grafting (CABG) patients. Our previous studies found that the IL-6 produced by the atrium is positively related to the development of sPOAF. However, the causal relationship between IL-6 and sPOAF is not established. Purpose This study aims to explore the potential causality between atrial IL-6 and spontaneous AF(sAF), alongside assessing the impact of IL-6 on the electrophysiological properties of atrial myocytes (AM). Methods To determine the causal link between IL-6 and sAF, mice were randomly divided into eight groups: seven receiving injections of varying doses of recombinant IL-6 protein groups (15ng/kg to180ng/kg) into the left atrial wall, and one control group (vehicle). Mice were monitored for sAF for 7 days using implanted telemetry device. At 48 hrs post-injection, the left atrial appendages of another set of mice were collected for analyzing levels of IL-6, Myeloperoxidase (MPO), Transforming Growth Factor-β1 (TGF-β1), and Tumor Necrosis Factor-α (TNF-α). To assess the effect of IL-6 on the electrophysiological characteristics of AM, AMs were isolated from the hearts of 12-week-old mice and divided into experimental and control groups for electrophysiological testing. The experimental group was perfused with extracellular solutions containing 100 ng/mL of IL-6 while the control group was perfused with standard extracellular solutions. The measurements focused on action potential (AP), transient outward potassium current (Ito), and inward rectifier potassium current (Ik1) after a 30-minute perfusion. Results As depicted in Fig. 1A, a dose-response relationship between IL-6 levels and sAF occurrence was observed, with incidence increasing from 0% at 15 ng/kg to 75% at 180 ng/kg (χ²= 16.691, P = 0.005). The injection of IL-6 also induced the production of MPO, TGF-β1, and TNF-α with a dose-dependent effects (Fig. 2). In comparison to control, the AP duration at 90% (APD90) and APD50 of repolarization of atrial myocytes were significantly shortened in IL-6 group (Fig. 1B). For voltages from -10mV to +70mV, atrial myocytes in the IL-6 group showed significantly lower Ito current density than those in the control (Fig. 1C). No significant alterations were observed in the impact of IL-6 on Ik1 current density in atrial myocytes (Fig.1D). Conclusion To the best of our knowledge, this is the first study that experimentally tested the causal relation between IL-6 and sAF. The injection of IL-6 could cause the onset of sAF and produce MPO, TGF-β1, and TNF-α with a significant dose-dependent effect. The effect of IL-6 on inducing sAF might be through its effect on reducing APD and Ito current density in mouse atrial myocytes. This suggests that inhibition of atrial IL-6 might be a potential novel sPOAF prevention strategy.