Stimulatory Capacity Research Articles

Graphene-ophicalcite heterogeneous composite sponge for rapid hemostasis

Synergistic functionalization of interface coagulation stimulation and liquid absorption capacity is the key to improve the hemostatic efficiency of hemostats. Herein, we prepared a graphene-ophicalcite (OPH) heterogeneous composite sponge (GOCS) by using the heterogeneous gradient composite strategy. The sponge took cross-linked graphene sponge (CGS) as the main skeleton, allowing the OPH to be controllably positioned on the surface of GOCS. The heterogeneous strategy gave full play to the advantages of the material. On the one hand, GOCS had excellent liquid absorption ability, which enriched blood cells and other coagulation components at the wound interface after contacting blood. On the other hand, the OPH at the interface obviously activated platelets and rapidly triggered coagulation cascade reactions, exhibiting fast response and feedback characteristics for coagulation signals. Under the synergistic effects, the blood clotting index value of GOCS was reduced to 33.87 ± 9.97%, which was significantly lower than those of OPH (46.33 ± 16.85%) and CGS (67.53 ± 5.35%). Importantly, GOCS rapidly stopped bleeding within 51 s in the rat femoral artery model, suggesting its great potential in the field of hemostasis. Therefore, this study provides a new idea for the design and preparation of hemostatic materials via heterogeneous strategy.

Cofilin‐1 participates in the hyperfunction of myeloid dendritic cells in patients with severe aplastic anaemia

Cofilin‐1 interacts with actin to regulate cell movement. The importance of cofilin‐1 in immunity has been established, and its involvement in a number of autoimmune diseases has been confirmed. However, its role in severe aplastic anaemia (SAA) remains elusive. Thus, the aim of the current study was to investigate the role of cofilin‐1 in patients with SAA. Flow cytometry, Western blotting and real‐time quantitative reverse transcription‐polymerase chain reaction were performed to detect the mRNA and protein expression of cofilin‐1 in myeloid dendritic cells (mDCs) from patients with SAA. The expression of cofilin‐1 was then suppressed via siRNA, and its effects on mDCs and downstream effector T‐cell function were evaluated. Cofilin‐1 expression was higher in mDCs from patients with SAA and correlated with routine blood and immune indexes. Moreover, cofilin‐1 knockdown in mDCs from patients with SAA reduced their phagocytic capacity, migration capacity, and CD86 expression through F‐actin remodelling, downregulating the stimulatory capacity of mDCs on CD4+ and CD8+ T lymphocytes. Collectively, these findings indicate that cofilin‐1 participates in the hyperfunction of mDCs in patients with SAA and that the downregulation of cofilin‐1 in mDCs from patients with SAA could be a novel treatment approach for SAA.

CB2 engagement enhances group 2 innate lymphoid cell expansion and induction of airway hyperreactivity

Abstract Cannabinoids modulate the activation of immune cells and physiological processes in the lungs. Group 2 innate lymphoid cells (ILC2)s are central players in type-2 asthma, but how cannabinoids modulate ILC2 activation remains to be elucidated. Using a combination of cannabinoid receptor (CB)2 KO mice, a CB2 antagonist and agonist, we here provide evidence that CB2 signaling in ILC2s is important for the development of ILC2-driven airway inflammation in both mice and human. We show that both naïve and activated murine pulmonary ILC2s express CB2. CB2 signaling did not affect ILC2 homeostasis at steady state, but strikingly stimulated ILC2 proliferation and function upon activation using various models of airway inflammation including IL-33, IL-25 and Alternaria alternata. As a result, ILC2s lacking CB2 induced lower lung inflammation, as we made similar observations using a CB2 antagonist. Conversely, CB2 agonism remarkably exacerbated ILC2-driven airway hyperreactivity and lung inflammation. Mechanistically, transcriptomic and protein analysis revealed that CB2 signaling induced CREB phosphorylation in ILC2s. Human ILC2s expressed CB2, as CB2 antagonism and agonism showed opposing effects on ILC2 effector function and development of airway hyperreactivity in humanized mice. Collectively, our results define CB2 signaling in ILC2s as an important modulator of airway inflammation. Furthermore, our findings highlight the stimulatory capacity of cannabinoids on ILC2s and offer new therapeutic avenues, including the use of substances or pathways able to modulate CB2 and capable of alleviating lung function in patients with lung inflammation.

Anti-Tumor Potency of Short-Term Interleukin-15 Dendritic Cells Is Potentiated by In Situ Silencing of Programmed-Death Ligands

Dendritic cell (DC) vaccines have proven to be a valuable tool in cancer immune therapy. With several DC vaccines being currently tested in clinical trials, knowledge about their therapeutic value has been significantly increased in the past decade. Despite their established safety, it has become clear that objective clinical responses are not yet robust enough, requiring further optimization. Improvements of this advanced therapy medicinal product encompass, among others, regulating their immune stimulating capacity by in situ gene engineering, in addition to their implementation in combination therapy regimens. Previously, we have reported on a superior monocyte-derived DC preparation, including interleukin-15, pro-inflammatory cytokines and immunological danger signals in the culture process. These so-called IL-15 DCs have already proven to exhibit several favorable properties as cancer vaccine. Evolving research into mechanisms that could further modulate the immune response towards cancer, points to programmed death-1 as an important player that dampens anti-tumor immunity. Aiming at leveraging the immunogenicity of DC vaccines, we hypothesized that additional implementation of the inhibitory immune checkpoint molecules programmed death-ligand (PD-L)1 and PD-L2 in IL-15 DC vaccines would exhibit superior stimulatory potential. In this paper, we successfully implemented PD-L silencing at the monocyte stage in the 3-day IL-15 DC culture protocol resulting in substantial downregulation of both PD-L1 and PD-L2 to levels below 30%. Additionally, we validated that these DCs retain their specific characteristics, both at the level of phenotype and interferon gamma secretion. Evaluating their functional characteristics, we demonstrate that PD-L silencing does not affect the capacity to induce allogeneic proliferation. Ultimately designed to induce a durable tumor antigen-specific immune response, PD-L silenced IL-15 DCs were capable of surpassing PD-1-mediated inhibition by antigen-specific T cells. Further corroborating the superior potency of short-term IL-15 DCs, the combination of immune stimulatory components during DC differentiation and maturation with in situ checkpoint inhibition supports further clinical translation.

HIV-1 Trans Infection via TNTs Is Impeded by Targeting C5aR.

Nonadjacent immune cells communicate through a complex network of tunneling nanotubes (TNTs). TNTs can be hijacked by HIV-1, allowing it to spread between connected cells. Dendritic cells (DCs) are among the first cells to encounter HIV-1 at mucosal sites, but they are usually efficiently infected only at low levels. However, HIV-1 was demonstrated to productively infect DCs when the virus was complement-opsonized (HIV-C). Such HIV-C-exposed DCs mediated an improved antiviral and T-cell stimulatory capacity. The role of TNTs in combination with complement in enhancing DC infection with HIV-C remains to be addressed. To this aim, we evaluated TNT formation on the surface of DCs or DC/CD4+ T-cell co-cultures incubated with non- or complement-opsonized HIV-1 (HIV, HIV-C) and the role of TNTs or locally produced complement in the infection process using either two different TNT or anaphylatoxin receptor antagonists. We found that HIV-C significantly increased the formation of TNTs between DCs or DC/CD4+ T-cell co-cultures compared to HIV-exposed DCs or co-cultures. While augmented TNT formation in DCs promoted productive infection, as was previously observed, a significant reduction in productive infection was observed in DC/CD4+ T-cell co-cultures, indicating antiviral activity in this setting. As expected, TNT inhibitors significantly decreased infection of HIV-C-loaded-DCs as well as HIV- and HIV-C-infected-DC/CD4+ T-cell co-cultures. Moreover, antagonizing C5aR significantly inhibited TNT formation in DCs as well as DC/CD4+ T-cell co-cultures and lowered the already decreased productive infection in co-cultures. Thus, local complement mobilization via DC stimulation of complement receptors plays a pivotal role in TNT formation, and our findings herein might offer an exciting opportunity for novel therapeutic approaches to inhibit trans infection via C5aR targeting.

JAK1 signaling in dendritic cells promotes peripheral tolerance in autoimmunity through PD-L1-mediated regulatory Tcell induction.

Dendritic cells (DCs) induce peripheral Tcell tolerance, but cell-intrinsic signaling cascades governing their stable tolerogenesis remain poorly defined. Janus Kinase 1 (JAK1) transduces cytokine-receptor signaling, and JAK inhibitors (Jakinibs), including JAK1-specific filgotinib, break inflammatory cycles in autoimmunity. Here, we report in heterogeneous DC populations of multiple secondary lymphoid organs that JAK1 promotes peripheral Tcell tolerance during experimental autoimmune encephalomyelitis (EAE). Mice harboring DC-specific JAK1 deletion exhibit elevated peripheral CD4+ Tcell expansion, less regulatory Tcells (Tregs), and worse EAE outcomes, whereas adoptive DC transfer ameliorates EAE pathogenesis by inducing peripheral Tregs, programmed cell death ligand 1 (PD-L1) dependently. This tolerogenic program is substantially reduced upon the transfer of JAK1-deficient DCs. DC-intrinsic IFN-γ-JAK1-STAT1 signaling induces PD-L1, which is required for DCs to convert CD4+ Tcells into Tregs invitro and attenuated upon JAK1 deficiency and filgotinib treatment. Thus, DC-intrinsic JAK1 promotes peripheral tolerance, suggesting potential unwarranted DC-mediated effects of Jakinibs in autoimmune diseases.

Adenovirus vectors activate Vδ2+ γδT cells in a type I interferon-, TNF-, and IL-18-dependent manner.

Vδ2+ γδT cells are unconventional T cells that can be activated by cytokines without TCR signaling. Adenovirus vaccine vectors activated Vδ2+ γδT cells in an interleukin 18-, TNF-, and type I interferon-dependent manner. This stimulatory capacity was associated with adenovirus vectors of non-species C origin, including the ChAdOx1 vaccine platform.

Adrenergic control of the cardiovascular system in deer mice native to high altitude.

Studies of animals native to high altitude can provide valuable insight into physiological mechanisms and evolution of performance in challenging environments. We investigated how mechanisms controlling cardiovascular function may have evolved in deer mice (Peromyscus maniculatus) native to high altitude. High-altitude deer mice and low-altitude white-footed mice (P. leucopus) were bred in captivity at sea level, and first-generation lab progeny were raised to adulthood and acclimated to normoxia or hypoxia. We then used pharmacological agents to examine the capacity for adrenergic receptor stimulation to modulate heart rate (fH) and mean arterial pressure (Pmean) in anaesthetized mice, and used cardiac pressure-volume catheters to evaluate the contractility of the left ventricle. We found that highlanders had a consistently greater capacity to increase fH via pharmacological stimulation of β1-adrenergic receptors than lowlanders. Also, whereas hypoxia acclimation reduced the capacity for increasing Pmean in response to α-adrenergic stimulation in lowlanders, highlanders exhibited no plasticity in this capacity. These differences in highlanders may help augment cardiac output during locomotion or cold stress, and may preserve their capacity for α-mediated vasoconstriction to more effectively redistribute blood flow to active tissues. Highlanders did not exhibit any differences in some measures of cardiac contractility (maximum pressure derivative, dP/dtmax, or end-systolic elastance, Ees), but ejection fraction was highest in highlanders after hypoxia acclimation. Overall, our results suggest that evolved changes in sensitivity to adrenergic stimulation of cardiovascular function may help deer mice cope with the cold and hypoxic conditions at high altitude.

Immunosuppressive effect of Columbianadin on maturation, migration, allogenic T cell stimulation and phagocytosis capacity of TNF-α induced dendritic cells

Ethnopharmacological relevanceAngelicae pubescentis radix (APR) has a long history in the treatment of rheumatoid arthritis (RA) in China. It has the effects of dispelling wind to eliminate dampness, removing arthralgia and stopping pain in the Chinese Pharmacopeia, but its mechanisms was unclear. Columbianadin (CBN) was one of the main bioactive compounds of APR, and has many pharmacological effects. But the immunosuppressive effect of CBN on DCs and the potential mechanism needed to be explored. Aim of the studyThe study was aimed to clarify the immunosuppressive effect of CBN on maturation, migration, allogenic T cell stimulation and phagocytosis capacity of TNF-α induced DCs. Materials and methodsBone marrow-derived DCs were obtained and cultured from C57BL/6 mice in accordance with protocol. The phenotypic study (CD11c, CD40, CD80, CD86 and MHC Ⅱ) were measured by flow cytometry. FITC-dextran were uptaked by DCs and the change of endocytosis activity were mediated by acquired mannose receptor. Transwell chambers were used to detect the migration ability of DCs. Mixed leukocyte reaction (MLR) assay was used to detect the allostimulatory ability of CBN on TNF-α stimulated DCs. The secretion of cytokines and chemokines was measured by ELISA Kit. TLRs gene and MAPKs/NF-κB protein expression were checked by qRT-PCR and Western blot. ResultsCBN inhibited the maturation of TNF-α-induced DCs while maintaining phagocytosis capabilities. Additionally, CBN inhibited the migration of TNF-α stimulated DCs, which related to reduce the production of chemokines (MCP-1, MIP-1α). Notably, CBN could suppress the proliferation of CD4+T cells by inhibiting DCs maturation, and decrease the proinflammatory cytokines IL-6 production. Furthermore, CBN inhibited mRNA expression of TLR2, TLR7 and TLR9 in TNF-α-activated DCs. Meanwhile, the phosphorylation of p38, JNK1/2 and NF-κB protein were significantly inhibited in CBN treated DCs. ConclusionsThese findings provided novel insights into the pharmacological activity of CBN. They also indicated that inhibition DCs maturation owning to the immunosuppressive effect of CBN. CBN was expected as a potential immunosuppressant and TLRs/MAPKs/NF-κB pathway may be an important mechanism for CBN's immunosuppressive activity.

Functionally Active Antibodies to the Angiotensin II Type 1-Receptor Measured by a Luminometric Bioassay Do Not Correlate With Clinical Manifestations in Systemic Sclerosis: A Comparison With Antibodies to Vascular Receptors and Topoisomerase I Detected by ELISA.

Objectives1) To detect functionally active antibodies(abs) to the angiotensin II type-1-receptor (AT1R) by a novel luminometric assay. 2) To assess their prevalence in systemic sclerosis (SSc), other collagen disorders, as well as in further chronic inflammatory disorders including autoimmune, toxic and chronic viral diseases. 3) To compare these abs with anti-AT1R antibodies by ELISA as well as with antibodies to endothelin-type-A receptors (ETA1) and to topoisomerase I (topo-I) with respect to their specificity and clinical relevance.MethodsSera from 98 SSc-patients, 110 patients with other chronic inflammatory rheumatic disorders, 97 patients with autoimmune liver diseases, 57 patients with toxic or chronic viral liver diseases and 36 healthy controls were analyzed. A luminometric bioassay was established with Huh-7-cells constitutively expressing the AT1R. Patients’ sera were also tested by commercially available ELISA for anti-AT1R, -ETA1- and by an in-house ELISA for anti–topo-I-abs.ResultsFifty-two percent of the SSc-patients had functionally active anti-AT1R-abs with stimulatory (34%) or inhibitory capacity (18%). They were present also in up to 59% of patients with other rheumatic diseases but only 22% of healthy individuals (sensitivity 52%, specificity 53%). The functionally active antibodies detected by the luminometric assay did not correlate with anti-AT1R-, -ETA1- or -topo-I-abs measured by ELISA, but there was a strong correlation between anti-topo-I-, AT1R-, and -ETA1-ab reactivity measured by ELISA. Sensitivities of 55%, 28% and 47% and specificities of 66%, 87%, and 99% were calculated for these anti-AT1R-, -ETA1-, and anti-topo-I-abs, respectively. Functionally active abs did not correlate with disease severity or any organ manifestation. In contrast, abs to topo-I, AT1R, and ETA1 were associated with digital ulcers, pulmonary- and esophageal manifestation.ConclusionsFunctionally active anti-AT1R-abs can be detected in SSc-patients but do not correlate with disease activity. They are not specific for this disease and occur also in other autoimmune disorders and even viral or toxic diseases. Also, the vascular antibodies detected by ELISA are not SSc-specific but correlated with disease manifestations. In contrast, anti-topo-I-abs were confirmed to be a highly specific biomarker for both, diagnosis and organ manifestations of SSc.

In Vitro Generated Dendritic Cells of Leukemic Origin Predict Response to Allogeneic Stem Cell Transplantation in Patients With AML and MDS.

Allogeneic stem cell transplantation (alloSCT) is the treatment of choice for many patients with acute myeloid leukemia (AML) and myelodysplastic syndrome. The presentation of leukemic or allospecific antigens by malignant blasts is regarded as a crucial trigger for an effective allogeneic immune response. Conversely, insufficient stimulatory capacity by the leukemic blasts is thought to be a relevant escape mechanism from cellular immunotherapy (alloSCT). Our purpose was to test, whether the ability of malignant blasts to differentiate in vitro toward dendritic cells of leukemic origin (DCleu) is associated with clinical outcome. We isolated leukemic blasts from peripheral blood or bone marrow of AML and myelodysplastic syndrome patients before alloSCT (n=47) or at relapse after alloSCT (n=22). A panel of 6 different assays was used to generate DCleu in vitro. Results were correlated with clinical outcome. DCleu could be generated from all 69 samples. Significantly higher mean frequencies of DCleu were found in clinical long-term responders versus nonresponders to SCT (76.8% vs. 58.8%, P=0.006). Vice versa, the chance for response to SCT was significantly higher, if a DCleu+/dendritic cells (DC) ratio of >50% could be reached in vitro (P=0.004). Those patients were characterized by a longer time to relapse (P=0.04) and by a higher probability for leukemia-free survival (P=0.005). In vitro generation of DC and DCleu from leukemic blasts correlated with the clinical outcome. This observation may support a role of leukemic antigen presentation by "leukemia-derived DC" for the stimulation of an allogeneic immune response in AML.

Phase- targeted stimulation modulates phase-amplitude coupling in the motor cortex of the human brain

BackgroundPhase-amplitude coupling (PAC) in which the amplitude of a faster field potential oscillation is coupled to the phase of a slower rhythm, is one of the most well-studied interactions between oscillations at different frequency bands. In a healthy brain, PAC accompanies cognitive functions such as learning and memory, and changes in PAC have been associated with neurological diseases including Parkinson's disease (PD), schizophrenia, obsessive-compulsive disorder, Alzheimer's disease, and epilepsy. Objective/Hypothesis: In PD, normalization of PAC in the motor cortex has been reported in the context of effective treatments such as dopamine replacement therapy and deep brain stimulation (DBS), but the possibility of normalizing PAC through intervention at the cortex has not been shown in humans. Phase-targeted stimulation (PDS) has a strong potential to modulate PAC levels and potentially normalize it. MethodsWe applied stimulation pulses triggered by specific phases of the beta oscillations, the low frequency oscillations that define phase of gamma amplitude in beta-gamma PAC, to the motor cortex of seven PD patients at rest during DBS lead placement surgery We measured the effect on PAC modulation in the motor cortex relative to stimulation-free periods. ResultsWe describe a system for phase-targeted stimulation locked to specific phases of a continuously updated slow local field potential oscillation (in this case, beta band oscillations) prediction. Stimulation locked to the phase of the peak of beta oscillations increased beta-gamma coupling both during and after stimulation in the motor cortex, and the opposite phase (trough) stimulation reduced the magnitude of coupling after stimulation. ConclusionThese results demonstrate the capacity of cortical phase-targeted stimulation to modulate PAC without evoking motor activation, which could allow applications in the treatment of neurological disorders associated with abnormal PAC, such as PD.

024 Comparative analysis of ex vivo assays aimed at identifying Desmoglein 3 reactive CD4+ T cells in pemphigus vulgaris

Autoreactive CD4+ T cells against the desmosomal protein, Desmoglein 3 (Dsg3) play a central role in the pathogenesis of pemphigus vulgaris (PV). Accordingly, descriptive and functional analyses of these cells ex vivo are of great interest. Here, we investigated the phenotype and pathogenicity of CD4+ T cells within peripheral blood mononuclear cells of PV patients. Flow cytometric analysis enabled phenotyping of CD4+ T cells and even identification of Dsg3-reactive CD4+ T cells by using fluorochrome-labeled HLA-DRB1*04:02 multimers loaded with immunogenic Dsg3-peptides. Proliferation of CD3+CD4+ T cells was studied by CFSE-dye dilution in response to in vitro stimulation with Dsg3 protein or peptides. ELISpot analysis characterized cytokine- secretion profiles of CD4+ T cells in response to Dsg3-stimulation. In contrast to healthy controls, PV patients showed an increased number of activated CD4+ T cells with a stimulatory capacity. Dsg3-reactive CD4+ T cells were detected at low frequencies within PBMCs of PV patients. CD4+ T cells proliferated in response to specific Dsg3-peptides and especially IL-5 secretion was enhanced in PV even correlating with the clinical course. Our findings characterize Dsg3 reactive CD4+ T cells contributing to PV pathogenesis and thus serve as basis for the development of targeted therapies in the future.

188 Bacterial stimulation in the gut shapes hapten–driven skin inflammation

We addressed the functional role of microbiota in experimental contact hypersensitivity (CHS), a CD8+ Tc1–mediated cutaneous inflammatory model, which largely resembles allergic contact dermatitis in men. We found that germfree mice (GF) exhibited reduced ear swelling and cellular infiltration compared to conventionally housed (Conv) mice. To our surprise, hapten–specific Tc1 responses (proliferation, IFNγ production) were not altered in Conv and GF animals, excluding an effect of microbial stimualtion on T cell priming. Importantly, recolonized GF mice showed an unaffected CHS reaction, excluding a general defect in the GF immune system and a potent CHS–stimulatory capacity for microbiota in general. However, lymphocytes from skin–draining lymph nodes of CHS tolerant GF mice secreted higher amounts of IL10. Unexpectedly, ablation of the intestinal microbiota in mice, by an antibiotics (ABX) cocktail, completely mimicked the GF phenotype with regard to clinical symptoms, T cell response and IL10 secretion. This indicates that intestinal– but not cutaneous– microbiota shape immunity towards contact allergens. Moreover, a distinct set of bacteria was able to restore CHS immunity in total. Indicating that extent and quality of bacterial stimulation in the gut alter hapten–driven skin inflammation. Increased numbers of IL10 producing CD25+ CD4+ T cells and restoration of CHS responses in the absence of IL10 producing FOXP3+ Tregs in ABX treated mice demonstrated the functional relevance of T cell related IL10 in CHS inhibition. In absence of TLR2 signaling, the CHS response was restored in germ reduced mice. Interestingly, GF and ABX conditions restored IL10 secretion in TLR2 –deficient mice, demonstrating a role for TLR2 engagement upstream of Treg IL10 production.

Nanocomposite Hydrogels: A Promising Approach for Developing Stimuli-responsive Platforms and their Application in Targeted Drug Delivery

Introduction: With the development of hydrogels from half a century ago, their application in various medical fields, including drug delivery has been widely expanded. Hydrogels used in this field are produced with synthetic polymers such as polyvinylpyrrolidone, polyvinyl alcohol, or natural polymers like chitosan, agarose, and hyaluronic acid to develop biocompatible, biodegradable, and non-immunogenic drug carriers. However, limitations such as inadequate response to stimulation, low homogeneity, and poor loading capacity for hydrophobic drugs have limited the use of hydrogels for drug delivery due to the hydrophilic nature of the hydrogel. The use of nanoparticles in the structure of hydrogels to produce hydrogel nanocomposites leads to more diverse interactions such as hydrogen and electrostatic bonds in addition to covalent interactions between hydrogel polymers. In addition to enhancing the mechanical properties of the hydrogel and further homogeneity, these interactions lead to the formation of platforms responsive to various stimuli, attaining sustained release, and ameliorating the poor loading of hydrophobic drugs used in cancer treatment and wound dressing. Conclusion: A review of a research conducted in the last 20 years represents that the application of nanocomposite hydrogels in drug delivery includes a wide range of production methods, nanoparticles to create various stimulation mechanisms, and therapeutic applications. Indeed, research has been focused on developing smart systems for controlled release with stimuli to reduce side effects of conventional cancer treatment methods, such as chemotherapy, by targeting drug delivery and reducing drug administration frequency and mitigating chronic wound complications by the release of growth factors.

Synthesis of Ziziphus spina-christi (Jujube) Root Methanol Extract Loaded Functionalized Silver Nanoparticle (ZS-Ag-NPs); Physiochemical Characterization and Effect of ZS-Ag-NPs on Adipocyte Maturation, Adipokine and Vascular Smooth Muscle Cell Interaction.

In this research, a simple, green approach was employed to synthesize silver nanoparticles with the aid of Ziziphus spina-christi (L.) methanol root extract, which can act as a reducing, capping agent to treat obesity and inflammation. Globally, Ziziphus spina-christi (Jujube) root is used in traditional therapy as a lipolysis promoter. GC-MS results confirmed the availability of kaempferol (flavonol), cannabinol and indole-3-carboxylic acid in Ziziphus spina-christi root methanol extract (ZSE). ZSE silver nanoparticles (ZS-Ag-NPs) were synthesized and their effect on mitochondrial fatty acid oxidation capacity and adipokine levels in maturing adipocytes were analyzed. Maturing adipocytes treated with 0.4 µg/dL of ZSE and ZS-Ag-NPs significantly reduced the lipid content in adipocytes by 64% and 82%, respectively. In addition, lipolysis-related genes such as LPL (1.9 fold), HSL (2.3 fold), PGC-1α (3 fold), UCP-1 (4.1 fold), PRDM16 (2 fold) and PPARα (2.7 fold) increased significantly in ZS-Ag-NPs treated maturing adipocytes. The ZS-Ag-NPs treatment significantly decreased insulin resistance and metabolic inflammation-related LTB4-R, TNF-α, IL-4 and STAT-6 mRNA levels. Mitochondrial thermogenesis stimulating capacity of ZS-Ag-NPs was further confirmed by the significantly enhanced CREB-1 and AMPK protein levels in adipocytes. Furthermore, ZS-Ag-NPs treated adipokines (condition media, CM) were treated with human umbilical vein endothelial cells (HUVECs) to determine cytotoxicity and pro-inflammatory stimulus capacity. We found that ZS-Ag-NPs treated adipocyte CM effectively increased mRNA expression levels of the vascular endothelial cell growth factor (VEGF), and down-regulated oxidative stress (LPO, eNOS, and HO) and vascular cell inflammation (ICAM, VCAM, TNF-α, IL-1β, and NF-κB). In conclusion, ZS-Ag-NPs displayed an action at the molecular level in mitochondrial fatty acid oxidation, decreased adipokine secretion in adipocytes, and enhanced vascular endothelial cell growth. This molecular mechanical action of ZS-Ag-NPs reduced effectively obesity progressions and metabolic inflammatory pathogenesis associated with aging.

Parkinson\u2019s disease patients\u2019 short chain fatty acids production capacity after in vitro fecal fiber fermentation

Animal models indicate that butyrate might reduce motor symptoms in Parkinson’s disease. Some dietary fibers are butyrogenic, but in Parkinson’s disease patients their butyrate stimulating capacity is unknown. Therefore, we investigated different fiber supplements’ effects on short-chain fatty acid production, along with potential underlying mechanisms, in Parkinson’s patients and age-matched healthy controls. Finally, it was investigated if this butyrate production could be confirmed by using fiber-rich vegetables. Different fibers (n = 40) were evaluated by in vitro fermentation experiments with fecal samples of Parkinson’s patients (n = 24) and age-matched healthy volunteers (n = 39). Short-chain fatty acid production was analyzed by headspace solid-phase micro-extraction gas chromatography-mass spectrometry. Clostridium coccoides and C. leptum were quantified through 16S-rRNA gene-targeted group-specific qPCR. Factors influencing short-chain fatty acid production were investigated using linear mixed models. After fiber fermentation, butyrate concentration varied between 25.6 ± 16.5 µmol/g and 203.8 ± 91.9 µmol/g for Parkinson’s patients and between 52.7 ± 13.0 µmol/g and 229.5 ± 42.8 µmol/g for controls. Inulin had the largest effect, while xanthan gum had the lowest production. Similar to fiber supplements, inulin-rich vegetables, but also fungal β-glucans, stimulated butyrate production most of all vegetable fibers. Parkinson’s disease diagnosis limited short-chain fatty acid production and was negatively associated with butyrate producers. Butyrate kinetics during 48 h fermentation demonstrated a time lag effect in Parkinson’s patients, especially in fructo-oligosaccharide fermentation. Butyrate production can be stimulated in Parkinson’s patients, however, remains reduced compared to healthy controls. This is a first step in investigating dietary fiber’s potential to increase short-chain fatty acids in Parkinson’s disease.

CD169 Defines Activated CD14+ Monocytes With Enhanced CD8+ T Cell Activation Capacity.

Monocytes are antigen-presenting cells (APCs) that play diverse roles in promoting or regulating inflammatory responses, but their role in T cell stimulation is not well defined. In inflammatory conditions, monocytes frequently show increased expression of CD169/Siglec-1, a type-I interferon (IFN-I)-regulated protein. However, little is known about the phenotype and function of these CD169+ monocytes. Here, we have investigated the phenotype of human CD169+ monocytes in different diseases, their capacity to activate CD8+ T cells, and the potential for a targeted-vaccination approach. Using spectral flow cytometry, we detected CD169 expression by CD14+ CD16- classical and CD14+ CD16+ intermediate monocytes and unbiased analysis showed that they were distinct from dendritic cells, including the recently described CD14-expressing DC3. CD169+ monocytes expressed higher levels of co-stimulatory and HLA molecules, suggesting an increased activation state. IFNα treatment highly upregulated CD169 expression on CD14+ monocytes and boosted their capacity to cross-present antigen to CD8+ T cells. Furthermore, we observed CD169+ monocytes in virally-infected patients, including in the blood and bronchoalveolar lavage fluid of COVID-19 patients, as well as in the blood of patients with different types of cancers. Finally, we evaluated two CD169-targeting nanovaccine platforms, antibody-based and liposome-based, and we showed that CD169+ monocytes efficiently presented tumor-associated peptides gp100 and WT1 to antigen-specific CD8+ T cells. In conclusion, our data indicate that CD169+ monocytes are activated monocytes with enhanced CD8+ T cell stimulatory capacity and that they emerge as an interesting target in nanovaccine strategies, because of their presence in health and different diseases.

Iridium Oxide Nanoparticle–Protein Corona Neural Interfaces with Enhanced Electroactivity and Bioactivity Enable Electrically Manipulatable Physical and Chemical Neuronal Activation

AbstractIridium oxide (IrOx) is a promising implantable electrode material owing to its remarkable neural stimulation capacity. However, presently, IrOx electrodes lack biocompatibility and bioactive interactions with nerve tissues. Application of polymeric surface coatings results in a weak physical adhesion at the organic/inorganic interface, which limits their wide‐scale application. Herein, a smart iridium oxide‐plasma protein (IrOx‐PP) electrode with enhanced electroactivity, electrochemical stability, cytocompatibility, and bioactivity that can provide controllable topographical, electrical, and chemical stimuli to enhance neuronal activity is proposed. In the inorganic/organic nanoparticle (NP)‐protein corona structures, the soft NP‐corona led to repeated burst‐to‐zero‐to‐burst PP release, while the hard NP‐corona with an ordered atomic structure enhanced the electrochemical stability and bioactivity. The incorporated PP resulted in a higher current storage capacity, lower impedance, better cell growth, and significant neurite outgrowth compared with those obtained with pristine IrOx. The application of electrical stimulation to IrOx‐PP enabled simultaneous neuromodulation, on‐demand PP release, and cell uptake, with a 2‐fold higher cell density and significant neurite outgrowth on IrOx‐PP than on pristine IrOx. This bioactive inorganic‐organic hybrid electrode with the combined features of physical properties and improved neuromodulation is expected to be a revolutionary platform for efficient and biocompatible neural implantation.

β-(1→4)-Mannobiose Acts as an Immunostimulatory Molecule in Murine Dendritic Cells by Binding the TLR4/MD-2 Complex.

Some β-mannans, including those in coffee bean and soy, contain a mannose backbone with β-(1→4) bonds. Such mannooligosaccharides could have immunological functions involving direct interaction with immune cells, in addition to acting as prebiotics. This study aimed at assessing the immunological function of mannooligosaccharides with β-(1→4) bond, and elucidating their mechanism of action using bone marrow-derived murine dendritic cells (BMDCs). When BMDCs were stimulated with the mannooligosaccharides, only β-Man-(1→4)-Man significantly induced production of cytokines that included IL-6, IL-10, TNF-α, and IFN-β, and enhanced CD4+ T-cell stimulatory capacity. Use of putative receptor inhibitors revealed the binding of β-Man-(1→4)-Man to TLR4/MD2 complex and involvement with the complement C3a receptor (C3aR) for BMDC activation. Interestingly, β-Man-(1→4)-Man prolonged the production of pro-inflammatory cytokines (IL-6 and TNF-α), but not of the IL-10 anti-inflammatory cytokine during extended culture of BMDCs, associated with high glucose consumption. The results suggest that β-Man-(1→4)-Man is an immunostimulatory molecule, and that the promotion of glycolysis could be involved in the production of pro-inflammatory cytokine in β-Man-(1→4)-Man-stimulated BMDCs. This study could contribute to development of immune-boosting functional foods and a novel vaccine adjuvant.