Cytokine Production In Response Research Articles

Characteristics of the proinflammatory response of monocytes/macrophages in patients with metabolic syndrome, exemplified by the production of IL-6 and MCP-1

Metabolic syndrome (MS) is one of the most common socially significant diseases. Around 1.9 billion people suffer from this disease, which places an enormous burden on healthcare systems around the world. This is particularly true in connection with concomitant diseases. With the progression of MS, disorders in the function of the immune system occur in the body, including those associated with mitochondrial dysfunction, leading to the development of chronic inflammation. In particular, there is an increase in the number of circulating monocytes actively recruited to inflamed adipose tissue, where there is non-specific proinflammatory activation of innate immune cells, which adopt an M1-like phenotype and become less sensitive to anti-inflammatory stimuli. This ultimately leads to a decrease in the functional activity of monocytes/macrophages and their immunoplasticity. The subject of the study was the venous blood of patients and the CD14+ monocytes/macrophages obtained from it by immunomagnetic separation. In our work, we focused on the search for significant relationships between markers of chronic inflammation and the formation of immune tolerance of monocytes/macrophages in patients with metabolic syndrome. Biochemical parameters, basal and LPS-stimulated production of proinflammatory cytokines (IL-6 and MCP-1) were investigated by culture of monocytes/macrophages in patients with metabolic syndrome. The evaluation of biochemical parameters in blood samples from MS patients and healthy donors revealed that the levels of ALAT, AST, GGT, alkaline phosphatase, uric acid, C-reactive protein, glucose and insulin were significantly higher in MS patients than in healthy donors. The levels of P-amylase and high-density lipoprotein were significantly lower than in the control group. Within the experimental model, repeated stimulation showed a decrease in cytokine production in response to LPS compared to the first stimulation on day 7. It was also found that the response to the primary stimulus was higher in cells from patients with a body mass index (BMI) 40 kg/m2, which could indirectly indicate the presence of a phenotype associated with chronic inflammation and consequently with reduced plasticity of the monocyte/macrophage immune response.

Antibody blockade of the PSGL-1 immune checkpoint enhances T-cell responses to B-cell lymphoma.

Despite advancements in cancer immunotherapy, most lymphomas remain unresponsive to checkpoint inhibitors. P-selectin glycoprotein ligand-1 (PSGL-1), recently identified as a promoter of T-cell exhaustion in murine melanoma models, has emerged as a novel immune checkpoint protein and promising immunotherapeutic target. In this study, we investigated the potential of PSGL-1 antibody targeting in B-cell lymphoma. Using allogeneic co-culture systems, we demonstrated that targeted antibody interventions against human PSGL-1 enhanced T-cell activation and effector cytokine production in response to lymphoma cells. Moreover, in vitro treatment of primary lymphoma cell suspensions with PSGL-1 antibody resulted in increased activation of autologous lymphoma-infiltrating T cells. Using the A20 syngeneic B-cell lymphoma mouse model, we found that PSGL-1 antibody treatment significantly slowed tumor development and reduced the endpoint tumor burden. This antitumoral effect was accompanied by augmented tumor infiltration of CD4+ and CD8+ T cells and reduced infiltration of regulatory T cells. Finally, anti-PSGL-1 administration enhanced the expansion of CAR T cells previously transferred to mice bearing the aggressive Eμ-Myc lymphoma cells and improved disease control. These results demonstrate that PSGL-1 antibody blockade bolsters T-cell activity against B-cell lymphoma, suggesting a potential novel immunotherapeutic approach for treating these malignancies.

IL-7Rα on CD4+ T cells is required for their survival and the pathogenesis of experimental autoimmune encephalomyelitis

BackgroundThe IL-7 receptor alpha (IL-7Rα) binds both IL-7 and thymic stromal lymphopoietin (TSLP). IL-7Rα is essential for the development and survival of naive CD4+ T cells and their differentiation to effector/memory CD4+ T cells. Mice lacking IL-7Rα have severe lymphopenia and are resistant to experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis. However, it has been reported that IL-7Rα on peripheral CD4+ T cells is disposable for their maintenance and EAE pathogenesis, which does not align with the body of knowledge on the role of IL-7Rα in the biology of CD4+ T cells. Given that a definitive study on this important topic is lacking, we revisited it using a novel approach, an inducible knockout of the IL-7Rα gene in CD4+ T cells.MethodsWe generated Il7rafl/fl/CD4CreERT2 double transgenic mouse line (henceforth CD4ΔIl7ra), susceptible to tamoxifen-induced knockout of the IL-7Rα gene in CD4+ T cells. CD4ΔIl7ra mice were immunized with MOG35 − 55 for EAE induction and monitored for disease development. The expression of IL-7Rα, CD4+ T cell numbers, and MOG35 − 55-specific CD4+ T cell response was evaluated in the central nervous system (CNS) and lymphoid tissues by flow cytometry. Additionally, splenocytes of CD4ΔIl7ra mice were stimulated with MOG35 − 55 to assess their proliferative response and cytokine production by T helper cells.ResultsLoss of IL-7Rα from the surface of CD4+ T cells in CD4ΔIl7ra mice was virtually complete several days after tamoxifen treatment. The loss of IL-7Rα in CD4+ T cells led to a gradual and substantial decrease in their numbers in both non-immunized and immunized CD4ΔIl7ra mice, followed by slow repopulation up to the initial numbers. CD4ΔIl7ra mice did not develop EAE. We found a decrease in the total numbers of TNF-, IFN-γ-, IL-17 A-, and GM-CSF-producing CD4+ T cells and regulatory T cells in the spleens and CNS of immunized CD4ΔIl7ra mice. Tracking MOG35 − 55-specific CD4+ T cells revealed a significant reduction in their numbers in CD4ΔIl7ra mice and decreased proliferation and cytokine production in response to MOG35 − 55.ConclusionOur study demonstrates that IL-7Rα on peripheral CD4+ T cells is essential for their maintenance, immune response, and EAE pathogenesis.

Plasma polyamines during pregnancy and their relationships with maternal allergies and the immune response of the neonates

AbstractBackgroundSome studies have reported that polyamine levels may influence immune system programming. The aim of this study was to evaluate the polyamine profile during gestation and its associations with maternal allergy and cytokine production in cord blood cells in response to different allergenic stimuli.MethodsPolyamines were determined in plasma of pregnant women (24 weeks, N = 674) and in umbilical cord samples (N = 353 vein and N = 160 artery) from the Mediterranean NELA birth cohort. Immune cell populations were quantified, and the production of cytokines in response to different allergic and mitogenic stimuli was assessed in cord blood.ResultsSpermidine and spermine were the most prevalent polyamines in maternal, cord venous, and cord arterial plasma. Maternal allergies, especially allergic conjunctivitis, were associated with lower spermine in umbilical cord vein. Higher levels of polyamines were associated with higher lymphocyte number but lower Th2‐related cells in cord venous blood. Those subjects with higher levels of circulating polyamines in cord showed lower production of inflammatory cytokines, especially IFN‐α, and lower production of Th2‐related cytokines, mainly IL‐4 and IL‐5. The effects of polyamines on Th1‐related cytokines production were uncertain.ConclusionsSpermidine and spermine are the predominant polyamines in plasma of pregnant women at mid‐pregnancy and also in umbilical cord. Maternal allergic diseases like allergic conjunctivitis are related to lower levels of polyamines in cord vein, which could influence the immune response of the newborn. Cord polyamine content is related to a decreased Th2 response and inflammatory cytokines production, which might be important to reduce an allergenic phenotype in the neonate.

Oxymatrine attenuates sepsis-induced inflammation and organ injury via inhibition of HMGB1/RAGE/NF-κB signaling pathway.

Sepsis is a life-threatening organ dysfunction that endangers patient lives and is caused by an imbalance in the host defense against infection. Sepsis continues to be a significant cause of morbidity and mortality in critically sick patients. Oxymatrine (OMT), a quinolizidine alkaloid derived from the traditional Chinese herb Sophora flavescens Aiton, has been shown to have anti-inflammatory effects on a number of inflammatory illnesses according to research. In this study, we aimed to evaluate the therapeutic effects of OMT on sepsis and explore the underlying mechanisms. We differentiated THP-1 cells into THP-1 macrophages and studied the anti-inflammatory mechanism of OMT in a lipopolysaccharide (LPS)-induced THP-1 macrophage sepsis model. Activation of the receptor for advanced glycation end products (RAGE), as well as NF-κB, was assessed by Western blot analysis and immunofluorescence staining. ELISA was used to measure the levels of inflammatory factors. We found that OMT significantly inhibited HMGB1-mediated RAGE/NF-κB activation and downstream inflammatory cytokine production in response to LPS stimulation. Finally, an in vivo experiment was performed on septic mice to further study the effect of OMT on injured organs. The animal experiments showed that OMT significantly inhibited HMGB1-mediated RAGE/NF-κB activation, protected against the inflammatory response and organ injury induced by CLP, and prolonged the survival rate of septic mice. Herein, we provide evidence that OMT exerts a significant therapeutic effect on sepsis by inhibiting the HMGB1/RAGE/NF-κB signaling pathway.

Phosphorylation of caspase-8 by RSKs via organ-constrained effects controls the sensitivity to TNF-induced death

Caspase-8 (Casp8) serves as an initiator of apoptosis or a suppressor of necroptosis in context-dependent manner. Members of the p90 RSK family can phosphorylate caspase-8 at threonine-265 (T265), which can inactivate caspase-8 for bypassing caspase-8-mediated blockade of necroptosis and can also decrease caspase-8 level by promoting its degradation. Mutating T265 in caspase-8 to alanine (A) in mice blocked TNF-induced necroptotic cecum damage but resulted in unexpectedly massive injury in the small intestine. Here, we show RSK1, RSK2, and RSK3 redundantly function in caspase-8 phosphorylation, and the duodenum is the most severely affected part of the small intestine when T265 phosphorylation of caspase-8 was prevented. Eliminating caspase-8 phosphorylation resulted in a duodenum-specific increase in basal caspase-8 protein level, which shall be responsible for the increased sensitivity to TNF-induced damage. Apoptosis of intestinal epithelial cells (IECs) was predominant in the duodenum of TNF-treated Rsk1−/−Rsk2−/−Rsk3−/− and Casp8T265A/T265A mice, though necroptosis was also observed. The heightened duodenal injury amplified systemic inflammatory responses, as evidenced by the contribution of hematopoietic cells to the sensitization of TNF-induced animal death. Further analysis revealed that hematopoietic and non-hematopoietic cells contributed differentially to cytokine production in response to the increased cell death. Collectively, RSKs emerges as a previously overlooked regulator that, via tissue/organ-constrained inactivating caspase-8 and/or downregulating caspase-8 protein level, controls the sensitivity to TNF-induced organ injury and animal death.

Metabolic Recovery with the Persistence of Proinflammatory Leucocyte Dysfunction After Bariatric Intervention for Obesity.

A suitable option for severe obesity treatment is a surgical approach. After surgery, metabolic markers and weight frequently return to adequate values; however, concerning systemic inflammatory mediators, the results are inconsistent. Furthermore, it has been suggested that leucocyte function may be affected even after weight normalization. This study aimed to determine if the surgical treatment of obesity influences the production of cytokines by LPS-stimulated as a function of leucocytes. We performed a cross-sectional study that investigated the production of cytokines in response to lipopolysaccharide (LPS) along a kinetic of simulation by leucocytes recovered from individuals with normal weight (NW, n = 8), persons living with obesity (Ob, n = 7), persons living with obesity and diabetes mellitus (Ob-DM, n = 17), and persons that used to live with obesity who underwent bypass surgery (fOb + bypass, n = 8) and recover normal weigh. IL-6 levels were significantly higher in the Ob and fOb + bypass groups than in NW (p = 0.043). IL-10 secretion without LPS was significantly higher in the NW group than in the other groups explored (p < 0.05). When exposed to LPS, the IL-10 levels increased in all groups except the NW group. As also observed for IL-18 and IL-33, the secretion curve of the fOb + bypass group was more similar to the Ob group, even when they had reached normal weight, as opposed to the NW group. Our results show that in patients with fOb + bypass, inflammatory and anti-inflammatory cytokine production dynamics remain disrupted even with improved metabolic control and normal weight recovery.

Immunometabolic adaptation in monocytes underpins functional changes during pregnancy

Metabolic heterogeneity is a determinant of immune cell function. The normal physiological metabolic reprogramming of pregnancy that ensures the fuel requirements of mother and baby are met, might also underpin changes in immunity that occur with pregnancy and manifest as altered responses to pathogens and changes to autoimmune disease symptoms. Using peripheral blood from pregnant women at term, we reveal that monocytes lose M2-like and gain M1-like properties accompanied by reductions in mitochondrial mass, maximal respiration, and cardiolipin content in pregnancy; glycolysis is unperturbed. We establish that muramyl dipeptide (MDP)-stimulated cytokine production relies on oxidative metabolism, then show in pregnancy reduced cytokine production in response to MDP but not LPS. Overall, mitochondrially centered metabolic capabilities of late gestation monocytes are down-regulated revealing natural plasticity in monocyte phenotype and function that could reveal targets for improving pregnancy outcomes but also yield alternative therapeutic approaches to diverse metabolic and/or immune-mediated diseases beyond pregnancy.

An elevated level of interleukin-17A in a Senegalese malaria cohort is associated with rs8193038 IL-17A genetic variant

Malaria infection is a multifactorial disease partly modulated by host immuno-genetic factors. Recent evidence has demonstrated the importance of Interleukin-17 family proinflammatory cytokines and their genetic variants in host immunity. However, limited knowledge exists about their role in parasitic infections such as malaria. We aimed to investigate IL-17A serum levels in patients with severe and uncomplicated malaria and gene polymorphism’s influence on the IL-17A serum levels. In this research, 125 severe (SM) and uncomplicated (UM) malaria patients and 48 free malaria controls were enrolled. IL-17A serum levels were measured with ELISA. PCR and DNA sequencing were used to assess host genetic polymorphisms in IL-17A. We performed a multivariate regression to estimate the impact of human IL-17A variants on IL-17A serum levels and malaria outcomes. Elevated serum IL-17A levels accompanied by increased parasitemia were found in SM patients compared to UM and controls (P < 0.0001). Also, the IL-17A levels were lower in SM patients who were deceased than in those who survived. In addition, the minor allele frequencies (MAF) of two IL-17A polymorphisms (rs3819024 and rs3748067) were more prevalent in SM patients than UM patients, indicating an essential role in SM. Interestingly, the heterozygous rs8193038 AG genotype was significantly associated with higher levels of IL-17A than the homozygous wild type (AA). According to our results, it can be concluded that the IL-17A gene rs8193038 polymorphism significantly affects IL-17A gene expression. Our results fill a gap in the implication of IL-17A gene polymorphisms on the cytokine level in a malaria cohort. IL-17A gene polymorphisms also may influence cytokine production in response to Plasmodium infections and may contribute to the hyperinflammatory responses during severe malaria outcomes.

TRPV4 Regulates the Macrophage Metabolic Response to Limit Sepsis-induced Lung Injury.

Sepsis is a systemic inflammatory response that requires effective macrophage metabolic functions to resolve ongoing inflammation. Previous work showed that the mechanosensitive cation channel, transient receptor potential vanilloid 4 (TRPV4), mediates macrophage phagocytosis and cytokine production in response to lung infection. Here, we show that TRPV4 regulates glycolysis in a stiffness-dependent manner by augmenting macrophage glucose uptake by GLUT1. In addition, TRPV4 is required for LPS-induced phagolysosome maturation in a GLUT1-dependent manner. In a cecal slurry mouse model of sepsis, TRPV4 regulates sepsis-induced glycolysis as measured by BAL fluid (BALF) lactate and sepsis-induced lung injury as measured by BALF total protein and lung compliance. TRPV4 is necessary for bacterial clearance in the peritoneum to limit sepsis-induced lung injury. It is interesting that BALF lactate is increased in patients with sepsis compared with healthy control participants, supporting the relevance of lung cell glycolysis to human sepsis. These data show that macrophage TRPV4 is required for glucose uptake through GLUT1 for effective phagolysosome maturation to limit sepsis-induced lung injury. Our work presents TRPV4 as a potential target to protect the lung from injury in sepsis.

Abstract WP162: Myelin Suppresses Macrophage Responses to Diverse Stimuli

Introduction: In intracerebral hemorrhage (ICH), blood-derived macrophages initially contribute to a neurotoxic inflammatory response. Understanding the endogenous signals that control this response could help limit these effects. Uptake of myelin debris limits macrophage inflammatory cytokine production in response to LPS, possibly due to the cholesterol present in myelin. However, the pathways by which myelin suppresses macrophage responses and the broader impacts of myelin on macrophage phenotype are poorly understood. Methods and Results: RNA sequencing was used to examine impacts of myelin in diverse conditions. BMDMs were pretreated with myelin, cholesterol or T0901317, an agonist of the cholesterol-response transcription factor LXR. The cells were stimulated with Type I cytokines, Type II cytokines, and different TLR agonists to mimic the diverse stimuli encountered in the inflamed brain (Fig 1A). Myelin suppressed responses to all stimulations, as did T0901317. Cholesterol suppressed the response to LPS and had little effect on other stimulations, including the ICH-relevant alarmin S100A9 (Fig 2). Gene Ontology Enrichment showed that many of the inflammatory gene pathways suppressed by myelin were unique for each stimulation although lipid metabolism pathways were shared across stimulations. Conclusions: Myelin broadly limits macrophage responses to diverse stimulations, partially though not completely through cholesterol and activation of LXR. Cholesterol does not suppress the response to S100A9, suggesting that other components of myelin or activation of phagocytic receptors contribute to suppression of the macrophage response during ICH.

Evidence of innate training in bovine γδ T cells following subcutaneous BCG administration.

The Bacillus Calmette Guerin (BCG) vaccine has been shown to induce non-specific protection against diseases other than tuberculosis in vaccinated individuals, attributed to the induction of trained immunity. We have previously demonstrated that BCG administration induces innate immune training in mixed peripheral blood mononuclear cells and monocytes in calves. Gamma Delta (γδ) T cells are non-conventional T cells that exhibit innate and adaptive immune system features. They are in higher proportion in the peripheral blood of cattle than humans or rodents and play an essential role in bovine immune response to pathogens. In the current study, we determined if BCG administration induced innate immune training in bovine γδ T cells. A group of 16 pre-weaned Holstein calves (2-4 d age) were enrolled in the study and randomly assigned to vaccine and control groups (n=8/group). The vaccine group received two doses of 106 colony forming units (CFU) BCG Danish strain subcutaneously, separated by 2 weeks. The control group remained unvaccinated. Gamma delta T cells were purified from peripheral blood using magnetic cell sorting three weeks after receiving the 1st BCG dose. We observed functional changes in the γδ T cells from BCG-treated calves shown by increased IL-6 and TNF-α cytokine production in response to in vitro stimulation with Escherichia coli LPS and PAM3CSK4. ATAC-Seq analysis of 78,278 regions of open chromatin (peaks) revealed that γδ T cells from BCG-treated calves had an altered epigenetic status compared to cells from the control calves. Differentially accessible peaks (DAP) found near the promoters of innate immunity-related genes like Siglec14, Irf4, Ifna2, Lrrfip1, and Tnfrsf10d were 1 to 4-fold more accessible in cells from BCG-treated calves. MOTIF enrichment analysis of the sequences within DAPs, which explores transcription factor binding motifs (TFBM) upstream of regulatory elements, revealed TFBM for Eomes and IRF-5 were among the most enriched transcription factors. GO enrichment analysis of genes proximal to the DAPs showed enrichment of pathways such as regulation of IL-2 production, T-cell receptor signaling pathway, and other immune regulatory pathways. In conclusion, our study shows that subcutaneous BCG administration in pre-weaned calves can induce innate immune memory in the form of trained immunity in γδ T cells. This memory is associated with increased chromatin accessibility of innate immune response-related genes, thereby inducing a functional trained immune response evidenced by increased IL-6 and TNF-α cytokine production.

Dual CAR-T Cells Targeting CD19 and CD37 Are Effective in Target Antigen Loss B-cell Tumor Models.

Chimeric antigen receptor T (CAR-T) cells targeting multiple antigens (Ag), may reduce the risk of immune escape following the loss of the target Ag and further increase the efficacy of treatment. We developed dual-targeting CAR-T cells that target CD19 and CD37 Ags and evaluated their antitumor effects. CD19/CD37 dual CAR-T cells were generated using cotransduction and simultaneous gene transfer of two types of lentiviral vectors transferring CD19CAR or CD37CAR genes, including the intracellular domains of CD28 and CD3ζ signaling domains. These dual CAR-T cells contained three fractions: CD19/CD37 bispecific CAR-T cells, single CD19CAR-T cells, and single CD37CAR-T cells. In the functional evaluation of CAR-T cells in vitro, CD19/CD37 dual CAR-T cells showed adequate proliferation and cytokine production in response to CD19 and CD37 antigen stimulation alone or in combination. Evaluation of intracellular signaling revealed that dual CAR-T cell-mediated signals were comparable with single CAR-T cells in response to CD19- and CD37-positive B-cell tumors. Although the cytotoxicity of CD19/CD37 dual CAR-T cells in both CD19- and CD37-positive B-cell tumors was similar to that of single CD19 and CD37CAR-T cells, against CD19 and CD37 Ag-heterogeneous tumor, dual CAR-T cells demonstrated significantly superior tumor lysis compared with single CAR-T cells. Furthermore, CD19/CD37 dual CAR-T cells effectively suppressed Ag-heterogeneous Raji cells in a xenograft mouse model. Collectively, these results suggest that CD19/CD37 dual CAR-T cells may be effective target-Ag-loss B-cell tumor models in vitro and in vivo, which represents a promising treatment for patients with relapsed/refractory B-cell malignancies.

Consequences of mitochondrial DNA depletion in microglial cells

AbstractBackgroundMitochondrial dysfunction is an early and prominent feature of Alzheimer’s disease (AD). We have recently published that lower brain mitochondrial DNA copy number (mtDNAcn) is associated with a greater odds of AD neuropathological change and worse cognitive performance. As it is known that microglial cells play an important role in AD, we want to address how a reduction in mtDNAcn may affect microglial function.Methodsmicroglial BV2 cells were treated with ethidium bromide (etbr) (1ug/ml) for 5 days to achieve a 95% reduction of mitochondrial‐encoded genes expression. Cells were characterized by RNAseq and Seahorse experiments. BV2 cells were challenged with latex beads and 10uM zymosan‐pHrodo for 24 hours and phagocytosis was analyzed by flow cytometry. BV2 cells were stimulated with LPS (100ng/ml) for 3 hours to measure cytokine release by qPCR and ELISA. After BV2 stimulation, fresh media (without LPS or etbr) was conditioned for 6 hours and collected to treat neurons (SH‐SY5Y cells) and human primary astrocytes for 24 hours. RNA and protein samples were collected.ResultsmtDNAcn reduction led to a dramatic reduction in oxidative phosphorylation and a mild reduction in proliferation. RNAseq data showed an increase in the hypoxia signature and cellular senescence, coupled with a reduction in biosynthetic process and response to interferon. No changes were observed in phagocytic capacity. However, after LPS stimulation, etbr‐treated cells showed a reduction in the production of IL1B and IL6 cytokines, suggesting an impairment in the response to challenge. Neurons exposed to media from etbr‐treated BV2 cells showed an increase in MAPT and APOE expression. Samples from astrocytes are currently being analyzed.ConclusionsmtDNAcn reduction impairs mitochondrial respiration, which affects the production of cytokines in response to stimulus and leads to cell senescence in microglial cells. Cytokines released by microglia affected neuronal expression of AD‐related genes.

Multiplex Prime Editing and PASSIGE TM for Non-Viral Generation of an Allogeneic CAR-T Cell Product

While CAR-T cell therapy represents a major advance in personalized immunotherapy, the autologous nature of commercially available CAR-T products have delayed its broad application beyond a subset of hematological malignancies. In particular, manufacturing autologous CAR-T therapies is costly and time-consuming, and success relies on the fitness of a patient's cells. An allogeneic off-the-shelf CAR-T product could overcome these cell quality and quantity issues and could be accessed on-demand. However, a successful allogeneic CAR-T product will require multiplex gene knockout in addition to stable CAR integration to prevent graft-versus-host disease (GvHD) and graft rejection by the patient's immune system. Strategies for the delivery and expression of CAR transgenes include semi-random integration using lentivirus or transposons, which risk unintended gene disruption or activation. Targeted integration can be achieved using nucleases in combination with a template for homology-directed repair (HDR), but efficiency of this approach is generally low and there are risks associated with the induction of double-strand breaks (DSBs), including p53 activation and chromothripsis. This is further complicated in a situation where multiplex editing is required, as multiple DSBs can lead to gross chromosomal rearrangements. Alternatively, base editors have been used for targeted gene disruption without the induction of DSBs via single nucleotide conversion to disrupt a splice site or introduce a single premature stop (pmSTOP) codon. However, this approach is limited to transition mutations and cannot be used to integrate large genetic cargo, which is required to generate CAR-T cells. Prime Editing (PE) can be used for precise and programmable gene disruption via multiple strategies, including introduction of multiple pmSTOP codons, splice site disruption, frameshift mutations, or deletion of large segments of regulatory or coding sequence. Further, Prime-Assisted Site-Specific Integrase Gene Editing (PASSIGE) can be used to precisely and flexibly integrate large genetic cargo at a specific locus. Together, PE-mediated gene knock out and PASSIGE can be tailored to generate a more broadly applicable, potentially safer, and more effective CAR-T cell product. To evaluate the efficacy of an all-PE non-viral approach to allogeneic CAR-T cell generation, PASSIGE and PE mediated gene knockout were used to generate CD19-CAR-T cells. Multiplex PE precisely disrupted expression of the endogenous T cell receptor alpha constant ( TRAC) and beta-2-microglobulin ( B2M) loci in over 90% of human T cells. Co-delivery of a non-viral DNA donor template with PASSIGE editing components resulted in targeted integration of a 3.5 kb CD19-CAR transgene expression cassette at the TRAC locus in over 60% of the T cells, with no observed impact on T cell viability, phenotype, or functionality. CD19 CAR-T cells generated using PASSIGE show potent anti-tumor activity and cytokine production in response to CD19 + tumor cell lines in vitro and in vivo. The PASSIGE-generated CD19 CAR-T cells reduce tumor burden and prolong survival of mice bearing CD19 + tumors. These results show that a PE platform can be used to generate multiplex edited CAR-T cells without the need for viral vectors and without causing DSBs. This modular, one-step, non-viral delivery Prime Editing platform expands the applicability of T cell therapies for the treatment of tumors and immune diseases.

Immunological Phenotyping of Mice with a Point Mutation in Cdk4.

Cyclin-dependent kinases (CDKs) play a crucial role in regulation of the mammalian cell cycle. CDK4 and CDK6 control the G1/S restriction checkpoint through their ability to associate with cyclin D proteins in response to growth factor signals. CDK4 deficiency in mice gives rise to a range of endocrine-specific phenotypes including diabetes, infertility, dwarfism, and atrophy of the anterior pituitary. Although CDK6 deficiency can cause thymic atrophy due to a block in the double-negative (DN) to double-positive (DP) stage of T cell development, there are no overt defects in immune cell development reported for CDK4-deficient mice. Here, we examined the impact of a novel N-ethyl-N-nitrosourea-induced point mutation in the gene encoding CDK4 on immune cell development. Mutant mice (Cdk4wnch/wnch) showed normal development and differentiation of major immune cell subsets in the thymus and spleen. Moreover, T cells from Cdk4wnch/wnch mice exhibited normal cytokine production in response to in vitro stimulation. However, analysis of the mixed bone marrow chimeras revealed that Cdk4wnch/wnch-derived T cell subsets and NK cells are at a competitive disadvantage compared to Cdk4+/+-derived cells in the thymus and periphery of recipients. These results suggest a possible role for the CDK4wnch mutation in the development of some immune cells, which only becomes apparent when the Cdk4wnch/wnch mutant cells are in direct competition with wild-type immune cells in the mixed bone marrow chimera.

Feeding Saccharomyces cerevisiae fermentation postbiotic products alters immune function and the lung transcriptome of preweaning calves with an experimental viral-bacterial coinfection

Bovine respiratory disease causes morbidity and mortality in cattle of all ages. Supplementing with postbiotic products from Saccharomyces cerevisiae fermentation (SCFP) has been reported to improve growth and provide metabolic support required for immune activation in calves. The objective of this study was to determine effects of SCFP supplementation on the transcriptional response to coinfection with bovine respiratory syncytial virus (BRSV) and Pasteurella multocida in the lung using RNA sequencing. Twenty-three calves were enrolled and assigned to 2 treatment groups: control (n = 12) or SCFP-treated (n = 11, fed 1 g/d SmartCare in milk and 5 g/d NutriTek on starter grain; both from Diamond V Mills Inc.). Calves were infected with ∼104 median tissue culture infectious dose per milliliter of BRSV, followed 6 d later by intratracheal inoculation with ∼1010 cfu of Pasteurella multocida (strain P1062). Calves were euthanized on d 10 after viral infection. Blood cells were collected and assayed on d 0 and 10 after viral infection. Bronchoalveolar lavage (BAL) cells were collected and assayed on d 14 of the feeding period (preinfection) and d 10 after viral infection. Blood and BAL cells were assayed for proinflammatory cytokine production in response to stimulation with lipopolysaccharide (LPS) or a combination of polyinosinic:polycytidylic acid and imiquimod, and BAL cells were evaluated for phagocytic and reactive oxygen species production capacity. Antemortem and postmortem BAL and lesioned and nonlesioned lung tissue samples collected at necropsy were subjected to RNA extraction and sequencing. Sequencing reads were aligned to the bovine reference genome (UMD3.1) and edgeR version 3.32.1 used for differential gene expression analysis. Supplementation with SCFP did not affect the respiratory burst activity or phagocytic activity of either lung or blood immune cells. Immune cells from the peripheral blood of SCFP-supplemented calves produced increased quantities of IL-6 in response to toll-like receptor stimulation, whereas cells from the BAL of SCFP-treated calves secreted fewer proinflammatory cytokines and less tumor necrosis factor-α (TNF-α) and IL-6 in response to the same stimuli. Transcriptional responses in lung tissues and BAL samples from SCFP-fed calves differed from the control group. The top enriched pathways in SCFP-treated lungs were associated with decreased expression of inflammatory responses and increased expression of plasminogen and genes involved in glutathione metabolism, supporting effective lung repair. Our results indicate that supplementing with SCFP postbiotics modulates both systemic and mucosal immune responses, leading to increased resistance to bovine respiratory disease.

Dimethyl Fumarate Protects against Lipopolysaccharide- (LPS-) Induced Sepsis through Inhibition of NF-κB Pathway in Mice.

Sepsis is one of the most severe complications and causes of mortality in the clinic. It remains a great challenge with no effective treatment for clinicians worldwide. Inhibiting the release of proinflammatory cytokines during sepsis is considered as an important strategy for treating sepsis and improving survival. In the present study, we have observed the effect of dimethyl fumarate (DMF) on lipopolysaccharide- (LPS-) induced sepsis and investigated the possible mechanism. By screening a subset of the Johns Hopkins Drug Library, we identified DMF as a novel inhibitor of nitric oxide synthesis in LPS-stimulated RAW264.7 cells, suggesting that DMF could be a potential drug to treat sepsis. To further characterize the effect of DMF on LPS signaling, TNF-α, MCP-1, G-CMF, and IL-6 expression levels were determined by using cytokine array panels. In addition, an endotoxemia model with C57BL/6 mice was used to assess the in vivo efficacy of DMF on sepsis. The survival rate was assessed, and HE staining was performed to investigate histopathological damage to the organs. DMF was found to increase the survival of septic mice by 50% and attenuate organ damage, consistent with the reduction in IL-10, IL-6, and TNF-α (inflammatory cytokines) in serum. In vitro experiments revealed DMF's inhibitory effect on the phosphorylation of p65, IκB, and IKK, suggesting that the primary inhibitory effects of DMF can be attributed, at least in part, to the inhibition of phosphorylation of IκBα, IKK as well as nuclear factor-κB (NF-κB) upon LPS stimulation. The findings demonstrate that DMF dramatically inhibits NO and proinflammatory cytokine production in response to LPS and improves survival in septic mice, raising the possibility that DMF has the potential to be repurposed as a new treatment of sepsis.

Subcutaneous Bacillus Calmette-Guérin Administration Induces Innate Training in Monocytes in Preweaned Holstein Calves.

The bacillus Calmette-Guérin (BCG) vaccine, administered to prevent tuberculosis, is a well-studied inducer of trained immunity in human and mouse monocytes. We have previously demonstrated that aerosol BCG administration induces innate training in calves. The current study aimed to determine whether s.c. BCG administration could induce innate training, identify the cell type involved, and determine whether innate training promoted resistance to bovine respiratory syncytial virus (BRSV) infection, a major cause of bovine respiratory disease in preweaned calves. A total of 24 calves were enrolled at 1-3 d of age and blocked by age into two treatment groups (BCG, n = 12; control, n = 12). BCG was given s.c. to preweaned calves. The control calves received PBS. We observed a trained phenotype, demonstrated by enhanced cytokine production in response to invitro stimulation with LPS (TLR-4 agonist) in PBMCs and CD14+ monocytes from the BCG group 2 wk (IL-1β, p = 0.002) and 4 wk (IL-1β, p = 0.005; IL-6, p = 0.013) after BCG administration, respectively. Calves were experimentally infected via aerosol inoculation with BRSV strain 375 at 5 wk after BCG administration and necropsied on day 8 postinfection. There were no differences in disease manifestation between the treatment groups. Restimulation of bronchoalveolar lavage fluid cells isolated on day 8 after BRSV infection revealed enhanced IL-1β (p = 0.014) and IL-6 (p = 0.010) production by the BCG group compared with controls. In conclusion, results from our study show that s.c. administration of the BCG vaccine can induce trained immunity in bovine monocytes and influence cytokine production in the lung environment after BRSV infection.

Effect of mevalonate, zoledronate and BCG on monocyte/macrophage phenotype

Cells of innate immunity, mainly monocytes/macrophages, form a long-term nonspecific immunological memory during the initial encounter with the pathogen, the so-called trained immunity. Mevalonate pathway metabolites play an important role in the formation of trained immunity. The aim of this investigation was to study the effect of modulators of mevalonate pathway, mevalonate and zoledronate, on the formation of trained immunity in human and animal monocytes/ macrophages.Material and methods. Human monocyte-like cell lines THP-1 and U-937, peritoneal macrophages of BALB/c mice were used. Trained immunity was induced in vitro by incubation of THP-1 and U-937 monocyte-like cell lines for 24 and 72 hours with inactivated Mycobacteria of BCG vaccine strain, and in vivo by intraperitoneal administration of BCG to BALB/c mice with isolation of peritoneal macrophages on day 7 after infection (lag phase). Cell hyperreactivity was assessed by response to a second stimulus with bacterial lipopolysaccharide (LPS) and mevalonate, zoledranate in the presence or absence of LPS. Lactate, cytokine (IL-1β, TNF-α, IL-10), nitric oxide and glucose level was measured in conditioned media from cells.Results and discussion. The study showed that monocyte-like cell lines THP-1 and U-937 responded differently by cytokine production, lactate, and glucose consumption to BCG stimulus in the presence or absence of lag phase. Mevalonate and zoledronate alone or in combination with LPS also stimulated cytokine production in different ways. The presence of lag phase for human monocyte-like cells is essential for the level of cytokine production and glucose consumption. Peritoneal macrophages have been shown to enhance pro-inflammatory cytokine production in response to LPS, mevalonate, and zoledronate.Conclusions. Mevalonate and zoledronate induce trained immunity in monocytes/macrophages.