TNF Production Research Articles

IMMU-23. ELIMINATING MONOCYTE CHEMOATTRACTION INVOKES COMPENSATORY NEUTROPHIL INFLUX AND PRONEURAL TO MESENCHYMAL TRANSITION IN GLIOBLASTOMA

Abstract Myeloid cells comprise the majority of immune cells in tumors, where their content and composition is determined by tumor type and driver mutation. While these cells are essential for shaping the tumor microenvironment, promoting tumor growth, and contributing to therapeutic resistance, targeting tumor-associated myeloid cells, including bone-marrow-derived monocytes and neutrophils, has not been successful in the clinics. Monocyte chemoattractant protein (MCP) family, comprising of Ccl2, Ccl7, Ccl8, Ccl12, are essential for monocytes trafficking to the tumor sites. To eliminate monocyte recruitment, we leveraged CRISPR/Cas-9 based gene editing tool to generate a mouse strain that is devoid of all MCP genes, which we termed quadruple MCP knockout (qMCP-/-). Using these mice in combination with genetically engineered mouse models (GEMM) of glioblastoma (GBM), we abolished tumor monocyte infiltration. Due to the functional redundancy of MCP family members, we show that targeting individual MCP genes leads to compensation by other MCPs. In contrast, when all MCPs are genetically deleted and monocyte recruitment is abolished, neutrophil infiltration ensues. Single-cell RNA sequencing revealed that intratumoral neutrophils promoted proneural-to-mesenchymal transition in GBM, and supported tumor aggression by facilitating hypoxia response via TNF production. Remarkably, pharmacologic or genetic interventions that suppress both monocytes and neutrophil infiltration improve the survival of GBM-bearing mice. Taken together, our findings establish that specific subsets of myeloid cells can influence the dynamism of tumor microenvironment, and they emphasize the importance of targeting both monocytes and neutrophils simultaneously for effective GBM immunotherapy.

Mast Cell Cytokines in Acute and Chronic Gingival Tissue Inflammation: Role of IL-33 and IL-37.

Much evidence suggests autoimmunity in the etiopathogenesis of periodontal disease. In fact, in periodontitis, there is antibody production against collagen, DNA, and IgG, as well as increased IgA expression, T cell dysfunction, high expression of class II MHC molecules on the surface of gingival epithelial cells in inflamed tissues, activation of NK cells, and the generation of antibodies against the azurophil granules of polymorphonuclear leukocytes. In general, direct activation of autoreactive immune cells and production of TNF can activate neutrophils to release pro-inflammatory enzymes with tissue damage in the gingiva. Gingival inflammation and, in the most serious cases, periodontitis, are mainly due to the dysbiosis of the commensal oral microbiota that triggers the immune system. This inflammatory pathological state can affect the periodontal ligament, bone, and the entire gingival tissue. Oral tolerance can be abrogated by some cytokines produced by epithelial cells and activated immune cells, including mast cells (MCs). Periodontal cells and inflammatory-immune cells, including mast cells (MCs), produce cytokines and chemokines, mediating local inflammation of the gingival, along with destruction of the periodontal ligament and alveolar bone. Immune-cell activation and recruitment can be induced by inflammatory cytokines, such as IL-1, TNF, IL-33, and bacterial products, including lipopolysaccharide (LPS). IL-1 and IL-33 are pleiotropic cytokines from members of the IL-1 family, which mediate inflammation of MCs and contribute to many key features of periodontitis and other inflammatory disorders. IL-33 activates several immune cells, including lymphocytes, Th2 cells, and MCs in both innate and acquired immunological diseases. The classic therapies for periodontitis include non-surgical periodontal treatment, surgery, antibiotics, anti-inflammatory drugs, and surgery, which have been only partially effective. Recently, a natural cytokine, IL-37, a member of the IL-1 family and a suppressor of IL-1b, has received considerable attention for the treatment of inflammatory diseases. In this article, we report that IL-37 may be an important and effective therapeutic cytokine that may inhibit periodontal inflammation. The purpose of this paper is to study the relationship between MCs, IL-1, IL-33, and IL-37 inhibition in acute and chronic inflamed gingival tissue.

TNF-induced metalloproteinase-9 production is associated with neurological manifestations in HTLV-1-infected individuals.

HTLV-1-infected individuals may develop a neurologic inflammatory condition known as HTLV-1-associated myelopathy (HAM/TSP), in which the high production of TNF is observed. These patients exhibit higher proviral loads, enhanced production of proinflammatory cytokines and lymphocyte proliferation in comparison to asymptomatic HTLV-1 carriers and those presenting overactive bladder (OAB-HTLV-infected). Metalloproteinases (MMPs) are known to degrade the components of the blood-brain barrier, favoring the migration of infected cells into the central nervous system. Moreover, the unbalanced production of MMPs and their inhibitors (TIMPs) has also been associated with tissue damage. The present work studied the production of MMP-9 and TIMPs in HTLV-1-infected individuals with and without neurological manifestations. HAM/TSP patients presented higher concentrations of MMP-9 in peripheral blood mononuclear cell (PBMC) culture supernatants, as well as a higher MMP-9/TIMP-3 ratio when compared to the other groups studied. MMP-9 levels positively correlated with proviral load and TNF in OAB-HTLV-infected individuals, and the in vitro neutralization of TNF significantly decreased MMP-9 levels in PBMC culture supernatants. Our findings indicate an association between MMP-9 production and the proinflammatory state associated with HTLV-1 infection, as well as HAM/TSP.

Precision Terminology: Why to Avoid the Term "Atypical Optic Neuritis".

Tuberculosis, one of the leading causes of death worldwide, stimulates inflammatory responses with beneficial and pathologic consequences. The regulation and nature of an optimal inflammatory response to <i>Mycobacterium tuberculosis</i> remains poorly understood in humans. Insight into mechanisms of negative regulation of the TLR-mediated innate immune response to <i>M. tuberculosis</i> could provide significant breakthroughs in the design of new vaccines and drugs. We hypothesized that TOLLIP and its common variants negatively regulate TLR signaling in human monocytes and are associated with susceptibility to tuberculosis. Using short hairpin RNA knockdown of TOLLIP in peripheral blood human monocytes, we found that TOLLIP suppresses TNF and IL-6 production after stimulation with TLR2 and TLR4 ligands. In contrast, secretion of the anti-inflammatory cytokine IL-10 was induced by TOLLIP. We also discovered two common polymorphisms that are associated with either decreased levels of mRNA expression (rs3750920) or increased IL-6 production (rs5743899) in a sample of 56 healthy volunteers. Furthermore, in a case-population study in Vietnam with 760 cord blood samples and 671 TB case patients, we found that SNPs rs3750920 and rs5743899 were associated with susceptibility to tuberculosis (<i>p</i> = 7.03 × 10⁻¹⁶ and 6.97 × 10⁻⁷, respectively). These data demonstrate that TOLLIP has an anti-inflammatory effect on TLR signaling in humans and that TOLLIP deficiency is associated with an increased risk of tuberculosis. To our knowledge, these data also show the first associations of TOLLIP polymorphisms with any infectious disease. These data also implicate an unexpected mechanism of negative regulation of TLR signaling in human tuberculosis pathogenesis.

Effect of cucurbiturils on cytokine production by peripheral blood mononuclear cells of healthy donors

Many drug delivery systems are currently under study, e.g., nanosized cavitands cucurbiturils, which, due to the presence of a cavity, can incorporate drug molecules. Since the immune system is quite sensitive to influence of nanomaterials and other cell-damaging factors, it is necessary to study immunosafety of the new delivery systems, i.e., immunotoxicity and immunomodulatory properties. The aim of this study was to investigate the effect of nanosized cucurbituril cavitands on the cytokine-producing ability of peripheral blood mononuclear cells in apparently healthy donors.&#x0D; Blood mononuclear cells (106/mL) were cultured in the presence of cucurbiturils at the following concentrations: 0.3 mM cucurbit[6]uril, 0.3 mM cucurbit[7]uril, and 0.01 mM cucurbit[8]uril for 72 h, under additional stimulation with aCD3 antibodies (1 g/mL), or without it. The level of cytokines in the supernatants was determined using enzyme immunoassay.&#x0D; It was shown that cucurbit[6]uril increased the level of spontaneous IL-4 production by 1.5 times (p 0.01) compared with the control. In the case of stimulated cytokine production, we found that cucurbit[6]uril reduced the level of IL-6, and also shows a tendency (p = 0.09) towards an increase in the IL-4 level. When cells were cultured with cucurbit[7]uril, we gave revealed a trend for increased production of pro-inflammatory TNF. It was also found that cucurbit[7]uril is able to suppress the production of IL-10 in aCD3-stimulated cell culture by 1.5 times. Cucurbit[8]uril was shown to inhibit production of cytokines in non-stimulated cell cultures. A significant decrease in the level of IFN and IL-10 was revealed as compared with the production of these cytokines in control cultures. When assessing the effect of cucurbit[8]uril on the IFN production upon stimulation with aCD3 antibodies, no significant differences were found, but there is also a trend for a decreased concentration of this cytokine agains control levels.&#x0D; Cucurbiturils can influence both spontaneous and stimulated production of cytokines by the blood mononuclear cells. The effect on cytokine-producing ability of the cells depends on the tested homologue compound.

Cytokine competent gut-joint migratory T Cells contribute to inflammation in the joint.

Although studies have identified the presence of gut-associated cells in the enthesis of joints affected by spondylarthritis (SpA), a direct link through cellular transit between the gut and joint has yet to be formally demonstrated. Using KikGR transgenic mice to label in situ and track cellular trafficking from the distal colon to the joint under inflammatory conditions of both the gut and joint, we demonstrate bona-fide gut-joint trafficking of T cells from the colon epithelium, also called intraepithelial lymphocytes (IELs), to distal sites including joint enthesis, the pathogenic site of SpA. Similar to patients with SpA, colon IELs from the TNFΔARE/+ mouse model of inflammatory bowel disease and SpA display heightened TNF production upon stimulation. Using ex vivo stimulation of photo-labeled gut-joint trafficked T cells from the popliteal lymph nodes of KikGR and KikGR TNFΔARE/+ we saw that the CD4+ photo-labeled population was highly enriched for IL-17 competence in healthy as well as arthritic mice, however in the TNFΔARE/+ mice these cells were additionally enriched for TNF. Using transfer of magnetically isolated IELs from TNF+/+ and TNFΔARE/+ donors into Rag1 -/- hosts, we confirmed that IELs can exacerbate inflammatory processes in the joint. Finally, we blocked IEL recruitment to the colon epithelium using broad spectrum antibiotics in TNFΔARE/+ mice. Antibiotic-treated mice had reduced gut-joint IEL migration, contained fewer Il-17A and TNF competent CD4+ T cells, and lessened joint pathology compared to untreated littermate controls. Together these results demonstrate that pro-inflammatory colon-derived IELs can exacerbate inflammatory responses in the joint through systemic trafficking, and that interference with this process through gut-targeted approaches has therapeutic potential in SpA.

Inhibition of mTOR in bovine monocyte derived macrophages and dendritic cells provides a potential mechanism for postpartum immune dysfunction in dairy cows

Dairy cattle experience a profound nutrient deficit postpartum that is associated with immune dysfunction characterized by heightened inflammation and reduced pathogen clearance. The activation of the central nutrient-sensing mTOR pathway is comparatively reduced in leukocytes of early postpartum dairy cows during this time of most pronounced nutrient deficit. We assessed the effect of pharmacological mTOR inhibition (Torin-1, rapamycin) on differentiation of monocyte derived classically (M1) and alternatively (M2) activated macrophages (MPh) and dendritic cells (moDC) from 12 adult dairy cows. Treatment with mTOR inhibitors generated M1 MPh with increased oxidative burst and expression of IL12 subunits but decreased phagocytosis and expression of IL1B, IL6, and IL10. In M2 MPh, treatment inhibited expression of regulatory features (CD163, ARG2, IL10) skewing the cells toward an M1-like phenotype. In moDC, mTOR inhibition increased expression of pro-inflammatory cytokines (IL12A, IL12B, IL1B, IL6) and surface CD80. In co-culture with mixed lymphocytes, mTOR-inhibited moDC exhibited a cytokine profile favoring a Th1 response with increased TNF and IFNG production and decreased IL10 concentrations. We conclude that mTOR inhibition in vitro promoted differentiation of inflammatory macrophages with reduced regulatory features and generation of Th1-favoring dendritic cells. These mechanisms could contribute to immune dysregulation in postpartum dairy cows.

Abstract IA04: Metabolic control of HCC initiation and progression

Abstract Non-alcoholic steatohepatitis (NASH) is quickly becoming the leading HCC etiology. NASH can lead to HCC by altering liver metabolism, inducing oncogenic mutations, causing tumor promoting inflammation as well as the immunosuppression of anti-HCC immunity. We have established an accurate model for studying NASH-induced HCC development, the MUP-uPA mouse, and used it to show that elevated TNF production by liver macrophages contributes to both NASH and HCC progression. The major cause of TNF induction during NASH is gut-derived endotoxin, whose infiltration into the portal circulation is enhanced by barrier disrupting diets that are high in fats or fructose. By disrupting autophagy and activating NF-kB, HFD feeding of MUP-uPA mice results in accumulation of p62, the major constituent of Mallory-Denk bodies, within hepatocytes. Accumulation of p62 is not required for induction of hepatosteatosis but it greatly accelerates and enhances NASH to HCC progression through the activation of NRF2 and mTORC1. Conditional activation of NRF2 in hepatocytes results in hepatomegaly due to induction of EGF and PDGF family members as well as altered liver metabolism, in part by triggering the degradation of fructose-1,6 bisphosphate phosphatase (FBP1). FBP1 is rate limiting for gluconeogenesis and its germ-line inherited deficiency results in a complex metabolic disorder that includes hypoglycemia, lactic acidosis, hepatomegaly, hepatosteatosis, hyperlipidemia and liver damage and is manifested only in response to glucose starvation. By generating Fbp1ΔHep mice, we found that FBP1 has enzymatic and non-enzymatic activities, the latter of which are due to formation of a multiprotein complex with aldolase B (ALDOB) and PP2A-C that interacts with AKT, dephosphorylates it and inhibits its activation. By inhibiting AKT activation, FBP1 and ALDOB suppress HCC development. Citation Format: Michael Karin, Li Gu, Yahui Zhu. Metabolic control of HCC initiation and progression [abstract]. In: Proceedings of the AACR Special Conference: Advances in the Pathogenesis and Molecular Therapies of Liver Cancer; 2022 May 5-8; Boston, MA. Philadelphia (PA): AACR; Clin Cancer Res 2022;28(17_Suppl):Abstract nr IA04.

Abstract 013: Microbial Metabolites Induce Pro-inflammatory Mechanisms In Children With Chronic Kidney Disease

Introduction: Chronic inflammation is a major risk factor for cardiovascular disease in chronic kidney disease (CKD). The underlying mechanisms are incompletely understood, but may be linked to gut dysbiosis. We aim to describe the microbiota-immune interaction in a cohort of pediatric CKD, thus independent of confounding comorbidities frequently seen in adult patients. Methods: We analyzed the fecal microbiome, plasma metabolites and peripheral immune phenotypes in 48 children (normal kidney function (HC, n=10), CKD stage G3-G4 (CKD, n=12), G5 treated by hemodialysis (HD, n=11) or kidney transplantation (KT, n=15)) with a mean age of 10.6 ± 3.8 (mean±SD) years. Results: Children exhibit stage-dependently increased cardiovascular risk as seen by the presence of arterial hypertension despite anti-hypertensive medication. Serum TNF-α (2.87±1.10 (HC); 7.54±2.29 (CKD); 9.63±2.73 (HD); 5.70 ± 1.66 (KT) pg/mL) and sCD14 (1.83±0.28 (HC); 2.88±0.47 (CKD); 2.83±0.69 (HD); 2.22±0.34 (KT) μg/mL) were elevated, indicating inflammation, gut barrier dysfunction and endotoxemia. We observed compositional and functional alterations of the microbiome, including a diminished production of short-chain fatty acids (e.g. propionate 10.43±5.49 (HC); 8.95±4.66 (CKD); 2.75±3.84 (HD); 12.49±4.89 (KT) μM). Plasma metabolite analysis revealed a stage-dependent increase of tryptophan metabolites of bacterial origin (e.g. indoxylsulfate). Serum from HD patients activated the aryl hydrocarbon receptor and stimulated TNF production in monocytes (fold change over HC: 1.80±0.61), corresponding to a pro-inflammatory shift from classical to non-classical and intermediate monocytes. Moreover, unsupervised analysis (FlowSOM) of T cells revealed a loss of mucosa-associated invariant T (MAIT) cells and regulatory T cell subtypes (e.g. CCR6+ and CXCR3+ subsets) in HD patients. Conclusions: In conclusion, gut barrier dysfunction and microbial metabolite imbalance mediate the pro-inflammatory immune phenotype in CKD. These dysbiosis-driven immunological changes are already detectable in children with CKD, in whom comorbidities usually found in adults are absent, highlights the specificity of CKD-related microbiota-immune interaction.

HDM induces distinct immunometabolic phenotype in macrophages in TLR4-dependent manner

Asthma is one of the most common chronic diseases. In many cases it is preceded by the development of an immune response to allergens such as animal fur, dust, pollens and etc. In human population this disease is heterogeneous, and no selective drugs are available at the moment for some endotypes of asthma. The role of the adaptive immune system in the pathogenesis of asthma was extensively studied, while the role of innate immune cells, in particular myeloid cells, was not sufficiently addressed. Myeloid cells, such as macrophages and dendritic cells, are characterized by high plasticity, heterogenicity and ability to undergo polarization in response to various pathogenic stimuli, including those engaging innate immune receptors. Recently, special attention was drawn to the link between polarization of macrophages and cell metabolism. We hypothesized that immunometabolic reprogramming of myeloid cells, in particular, of macrophages and dendritic cells during sensitization with an allergen may affect further immune response and asthma development. To test this hypothesis, we generated distinct types of myeloid cells in vitro from murine bone marrow and analyzed their immunometabolic profiles upon activation with house dust mite extract (HDM) and its key active components. We found that the combination of lipopolysaccharide (LPS) and beta-glucan is sufficient to upregulate proinflammatory cytokine production as well as respiratory and glycolytic capacity of myeloid cells, comparably to HDM. This specific immunometabolic phenotype was associated with altered mitochondrial morphology and possibly with increased ROS production in macrophages. Moreover, we found that both TNF production and metabolic remodeling of macrophages in response to HDM are TLR4-dependent processes. Altogether, these results expand our understanding of molecular mechanisms underlying asthma induction and pathogenesis and may potentially lead to new therapeutic strategies for the treatment of this disease.

Effects of Liposome-Entrapped Muramyl Tripeptide Phosphatidylethanolamine (L-MTP-PE) on the Tumor Growth and Survival of Mice Bearing Syngeneic Tumor in Combination with a Chemotherapeutic or Immunomodulatory Agent.

Antitumor activities of L-MTP-PE (Liposome entrapped myuramyl tripeptide phosphatidylethanolamine) in the combination treatment with chemo- or immune-therapeutic antitumor agents against various syngeneic tumors were tested.Against Meth A fibrosarcoma solid tumor system, L-MTP-PE showed slight but statistically significant elongation of survival days against 5-FU monotherapy in spite of its non-effect on tumor growth, when combined with 5-FU. Against liver metastasis model of M5076 carcinoma, L-MTP-PE showed a tendency of elongation of survival days by its single drug treatment, however, elongation with statistical significance was observed in the combination treatment with 5-FU in comparison with control group.These data suggest that L-MTP-PE seems to elongate the survival days of the solid tumor bearing mice and the liver metastasis model basically due to its saving effect on chemotherapeutic drug-induced immunosuppression. In the combination with an immunotherapeutic agent in mice, TNF production induced by another biological response modifier OK-432 was potentiated when primed with L-MTP-PE. L-MTP-PE also potentiate the antitumor effect of OK-432 possibly through the enhanced production of TNF-α. Combination of L-MTP-PE and OK-432 is considered to be a candidate for a new treatment model for cancer.

High-dimensional profiling reveals Tc17 cell enrichment in active Crohn’s disease and identifies a potentially targetable signature

The immune-pathology in Crohn’s disease is linked to dysregulated CD4+ T cell responses biased towards pathogenic TH17 cells. However, the role of CD8+ T cells able to produce IL-17 (Tc17 cells) remains unclear. Here we characterize the peripheral blood and intestinal tissue of Crohn’s disease patients (n = 61) with flow and mass cytometry and reveal a strong increase of Tc17 cells in active disease, mainly due to induction of conventional T cells. Mass cytometry shows that Tc17 cells express a distinct immune signature (CD6high, CD39, CD69, PD-1, CD27low) which was validated in an independent patient cohort. This signature stratifies patients into groups with distinct flare-free survival associated with differential CD6 expression. Targeting of CD6 in vitro reduces IL-17, IFN-γ and TNF production. These results identify a distinct Tc17 cell population in Crohn’s disease with proinflammatory features linked to disease activity. The Tc17 signature informs clinical outcomes and may guide personalized treatment decisions.

The stimulatory effect of fusobacteria on dendritic cells under aerobic or anaerobic conditions

Fusobacteria have been suspected to be pathobionts of colon cancer and inflammatory bowel disease. However, the immunomodulatory properties that affect these inflammatory reactions in dendritic cells (DCs) under anaerobic and aerobic conditions have not yet been characterized. We directly assessed the stimulatory effects of anaerobic commensal bacteria, including fusobacteria, on a human DC line through coculture under aerobic or anaerobic conditions. Under aerobic or anaerobic conditions, stimulation of the DC line with all live commensal bacteria examined, except the probiotic Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus), significantly increased the geometric mean fluorescent intensity (MFI) of marker proteins (HLA-ABC, HLA-DR, CD80, CD86, CD83, or CCR7) on the DC surface. In particular, both Fusobacterium nucleatum (F. nucleatum) and Escherichia coli (E. coli) significantly increased the expression of DC-associated molecules, except for CD83 under both aerobic and anaerobic conditions. The DC line stimulated with Fusobacterium varium (F. varium) significantly increased only CD80, HLA-ABC, and HLA-DR expression under anaerobic conditions. Moreover, differences in the levels of proinflammatory cytokines, such as IL-6, IL-8, and TNF-α, were detected in the DC line stimulated by all live commensal bacteria under either aerobic or anaerobic conditions. Under aerobic conditions, the DC line stimulated with E. coli produced significantly more IL-6, IL-8, and TNF-α than did the cells stimulated with any of the bacteria examined. When E. coli were used to stimulate the DC line under anaerobic conditions, TNF-α was predominantly produced compared to stimulation with any other bacteria. Compared to the DC line stimulated with any other bacteria, the cells stimulated with F. nucleatum showed significantly increased production of IL-6, IL-8 and TNF-α only under anaerobic conditions. In particular, E. coli, F. nucleatum, and F. varium strongly stimulated the DC line, resulting in significantly increased expression of surface molecules associated with DCs and production of inflammatory cytokines.

CD47 Promotes Autoimmune Valvular Carditis by Impairing Macrophage Efferocytosis and Enhancing Cytokine Production.

Systemic autoantibody-mediated diseases accelerate chronic cardiovascular disease in humans. In the K/B.g7 mouse model of spontaneous autoantibody-mediated inflammatory arthritis, valvular carditis arises in part because of Fc receptor-mediated activation of macrophages, leading to production of pathogenic TNF and IL-6. In this study, we explored whether impaired efferocytosis mediated by the interaction of CD47-expressing apoptotic cells with signal regulatory protein α (SIRPα) on macrophages contributes to disease progression in this model. CD47-expressing apoptotic cells and SIRPα+ macrophages were abundant in inflamed/rheumatic cardiac valves from both mice and humans. In vivo anti-CD47 blockade both prevented and treated valvular carditis in K/B.g7 mice. Blocking CD47 enhanced macrophage efferocytosis and reduced macrophage production of TNF and IL-6. These studies highlight the CD47:SIRPα interaction as a key driver of chronic cardiac valve inflammation and suggest these molecules as potential therapeutic targets to reduce cardiovascular disease risk in autoantibody-driven inflammatory diseases.

Abstract 212: Squamous cell carcinoma antigen counteracts the radiation-induced antitumor response by driving an immune evasion phenotype through STAT signaling

Abstract Radiation therapy (RT)-induced immune response shapes the tumor microenvironment, and is recognized as an essential mechanism for anti-tumor effect. RT promotes the release of neoantigens, damage-associated molecular patterns and cytokines leading to cytotoxic T cell infiltration and enhancing immune surveillance. However, RT-induced anti-tumor response is sometimes hampered by inhibitory signals that suppress T cell function and facilitate tumor immune evasion. Squamous cell carcinoma antigen (SERPINB3/SCCA1) is highly expressed in epithelial cancers including cervix, head and neck, lung, and esophagus, and often associated with poor prognosis. We found that overexpressing mSerpinb3a in Lewis lung carcinoma cells (LL2/mB3a) promoted tumor growth compared to LL2 transduced with control vector (LL2/C). Prior to RT, increased MDSCs, TAMs, and Treg cells were observed in LL2/mB3a tumors compared to LL2/C, and is associated with a shorter RT-induced tumor growth delay in LL2/mB3a. The total number of infiltrating T cells was significantly reduced in LL2/mB3a and LL2/C at 2 days post-RT, with recovery by 5 days post-RT. However, CD8+ T remained low in the LL2/mB3a tumors and showed decreased proliferative capacity compared to LL2/C infiltrating T cells. Importantly, while RT improved the functionality in LL2/C-infiltrating T cells, as shown by ex vivo stimulation resulting in increased TNF and INFγ production compared to non-RT LL2/C-infiltrating T cells, the same improvement was not observed in LL2/mB3a-infiltrating T cells. In human T cell in vitro assay, SERPINB3 inhibited T cell activation by suppressing CD69, and CD25 expression, resulting in impaired proliferation capability. Further study on the association between SERPINB3 and immunosuppression showed that LL2/mB3a had increased suppressive chemokine CXCL1 and S100A8/A9 expression compared to LL2/C tumors and RT further enhanced expression of these chemokines in LL2/mB3a tumors. Likewise, human cancer cells overexpressing SERPINB3 also secreted high levels of CXCL1/8 and S100A8/A9. This chemokine induction was found regulated by elevated phosphorylation of STAT1/3 in SERPINB3-expressing cancer cells, while inhibiting STAT signaling by Ruxolitinib significantly suppressed the SERPINB3-dependent chemokine expression. We found that cervical cancer patients with high pre-treatment serum SCCA level (&amp;gt;16.1 ng/ml) and p-STAT3 level is associated with worse outcome with cancer specific survival at 2 years of about 10% compared to patients with serum SCCA &amp;lt;16.1 and low pSTAT3 of 95%. Our findings indicate that SERPINB3 high tumors produce high levels of suppressive chemokines through STAT signaling, leading to MDSCs, macrophages, and Treg infiltration, which dampen T cell functionality and mitigate the effect of radiation therapy. Citation Format: Liyun Chen, Victoria Shi, Songyan Wang, Rebecca Freeman, Jin Zhang, Pippa Cosper, Catherine Spina, Julie Schwarz, Stephanie Markovina. Squamous cell carcinoma antigen counteracts the radiation-induced antitumor response by driving an immune evasion phenotype through STAT signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 212.

Abstract 2115: Glutamine blockade via prodrug JHU083 reprograms immunosuppressive tumor associated macrophages (TAMs) and drives tumor immunity in urologic cancers

Abstract Introduction: Metastatic prostate cancer is currently incurable and kills more than 30,000 men in the United States each year, making it the second leading cancer related cause of death and an area of unmet need. Previously, we reported increased infiltration of immunosuppressive CD206-positive tumor associated macrophages (TAMs) with disease progression in prostate adenocarcinoma.[1] Glutamine metabolism has been implicated in immunosuppressive TAMs as well as metastatic castration resistant prostate cancer (mCRPC)[2] and radioresistant urothelial carcinoma.[3] As such, we hypothesize that rational metabolic interventions could be a promising strategy to simultaneously target both TAMs and cancer cells, resulting in anti-tumor immunity. Methods: We utilized a novel pro-drug (JHU083) derived from 6-Diazo-5-oxo-L-norleucine (DON) which has significantly lowered toxicity to treat two urological syngeneic immunogenic mouse tumor models in vivo; B6CaP (prostate cancer) and MB49 (bladder cancer). We studied the direct effect on tumor cells, as well as the required immune compartment for drug efficacy in vivo using antibody targeted depletions or adoptively transferred TAMs. Moreover, we used RNA-sequencing and multi-parameter flow cytometry to characterize the effect of JHU083 on TAMs transcriptional programming and proteomic expression profiles in vivo. Lastly, we assessed the phagocytotic capacity of macrophages after treatment with JHU083 with flow cytometry and immunofluorescence (IF) microscopy. Results: JHU083 treatment showed significant tumor regression in both urologic cancer models. Using in vivo depletion of CD4 or CD8 T cells, or adoptively transferring previously in-vivo JHU083 treated TAMs we established a direct anti-tumor role of TAMs. These TAMs were more inflammatory as shown by the increased TNF-positivity. Strikingly, in the TME we also observed an increase of Glut1 and Hexokinase II indicating metabolic reprogramming of these TAMs towards glycolytic phenotype. Importantly, JHU083-treated TAMs showed significantly increased phagocytic activity of cancer cells, providing direct evidence of functional reprogramming. Conclusion: We found that JHU083 has two distinct functions in vivo; first, it directly impairs cancer cells which are glutamine dependent and second, it reprograms TAMs from an immunosuppressive to an inflammatory state via antagonism of glutamine metabolism in vivo. These macrophages convert to a highly glycolytic state, have increased TNF production, and have improved phagocytic activity against tumor cells. As urologic cancers are heavily infiltrated with immunosuppressive TAMs, JHU083 is an excellent preclinical candidate for these diseases. It remains to be seen if JHU083 treatment can be effectively combined with checkpoint therapy to elicit durable anti-tumor immunity. Citation Format: Monali Praharaj, Fan Shen, Liang Zhao, Thomas R. Nirschl, Laura Sena, Alok K. Singh, Debebe Theodros, Xiaoxu Wang, Raekwon A. Williams, Elizabeth Thompson, Ada Tam, Srinivasan Yegnasubramanian, Robert D. Leone, Jesse Al, Rana Rais, Barbara S. Slusher, Drew M. Pardoll, Jonathan D. Powell, Jelani C. Zarif. Glutamine blockade via prodrug JHU083 reprograms immunosuppressive tumor associated macrophages (TAMs) and drives tumor immunity in urologic cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2115.

Photodynamic anti-inflammatory activity of azulene derivatives on mammalian macrophages and their intracellular mechanism of action

Azulene derivatives have been studied previously as photodynamic therapy agents. They have anti-cancer, anti-microbial and anti-inflammatory activities. Together with their photodynamic activity they enable more control on their activation which aims to decrease possible side effects that have been encountered with their constitutively active drug counterparts. In our current study we focused on photodynamic anti-inflammatory activities of two azulene derivatives whose synthesis methods were described before. We found that when mammalian macrophages J774.2 cells were incubated with these two derivatives in the presence of LPS in dark conditions, these molecules had anti-inflammatory activity at their highest concentrations based on ELISA results on the pro-inflammatory cytokine levels. After light application, both derivatives exerted strong anti-inflammatory activities by substantially decreasing the TNF, IL6, GMCSF and IL12p40 cytokine production levels. When the intracellular mechanism of action for both derivatives was tested, only one of them acted through p38 and PI3K pathways whereas the other derivative did not affect either of these pathways. Our results suggest that these two azulene derivatives can be utilized as photodynamic anti-inflammatory drug candidates.

Pathogenicity and Growth Conditions Modulate Fonsecaea Extracellular Vesicles' Ability to Interact With Macrophages.

Chromoblastomycosis (CBM) is a chronic cutaneous and subcutaneous mycosis caused by black, dimorphic, and filamentous fungi of the Herpothrichiellaceae family, such as species of the genus Fonsecaea. These fungi can switch between the saprophytic forms (conidia and hyphae) and the pathogenic form, the muriform cells (MCs), which is considered an essential mechanism for fungal virulence. Nearly all types of cells can produce membranous structures formed by a lipid bilayer that communicate extracellularly with other cells, known as “extracellular vesicles” (EVs), which may act as virulence factors, as observed for several species of pathogenic fungi. Our findings demonstrated for the first time that F. pedrosoi, F. nubica, and F. erecta produce EVs in response to nutritional conditions. The EVs varied in sterol and protein contents, size, and morphology. Moreover, the EVs induced different cytokine and nitric oxide release patterns by bone marrow-derived macrophages (BMDMs). The EVs activated IL-1β production, possibly acting as the first signal in inflammasome activation. Unlike the pathogenic species, the EVs isolated from F. erecta did not significantly stimulate TNF and IL-10 production in general. Overall, these results demonstrated that different species of Fonsecaea produce EVs capable of modulating pro- and anti-inflammatory cytokine and nitric oxide production by BMDMs and that growth conditions affected the immunomodulatory capacities of the EVs as well as their size, content, and morphology.

Participation of MAPK and PI3K in Regulation of Cytokine Secretion by Peripheral Blood Monocular Cells in Response to Escherichia coli LPS and rDer p 2 Combination.

Search for the effective approaches to treat acute inflammation caused by combination of allergens and infectious agents is an important task for public health worldwide. House dust mites Dermatophagoides pteronyssinus are the source of allergens of the Der p groups and of microbial compounds, in particular, lipopolysaccharides (LPS). LPS and Der p 2 induce secretion of pro-inflammatory cytokines via activation of kinases p38 MAPK, MEK1/2, and PI3K. Participation of these kinases in the regulation of cells response to combined exposure to LPS and Der p 2 has not been sufficiently studied. We studied the effects of kinases (p38 MAPK, MEK1/2, and PI3K) inhibition on secretion of cytokines (TNF, IL-8, and IL-6) by peripheral blood mononuclear cells (PBMC) of healthy volunteers in response to E. coli LPS and rDer p 2. Contribution of kinases to the regulation of cell response to different agents (rDer p 2 and/or LPS) was revealed. It was found that p38 MAPK plays a key role in the regulation of secretion TNF by PBMC in response to the combination of LPS and rDer p 2. MEK1/2-dependent signaling is the main pathway for the synthesis of TNF and IL-8 in response to LPS and rDer p 2. PI3K-dependent signaling negatively regulates TNF production during rDer p 2-induced cell activation, but is not involved in the response to the combination of LPS and rDer p 2. PI3K-dependent signaling in the regulation of PBMC cytokine synthesis is most pronounced in response to their activation by rDer p 2. Understanding the mechanisms of immune cell responses to combinations of inflammatory agents could facilitate the search for new intracellular targets for anti-inflammatory therapy.

Novel urea-thiourea hybrids bearing 1,4-naphthoquinone moiety: Anti-inflammatory activity on mammalian macrophages by regulating intracellular PI3K pathway, and molecular docking study

In this study, four novel urea-thiourea hybrids bearing 1,4-naphthoquinone moiety were synthesized by the reaction of 2,3-diaminonaphthalene-1,4-dione and various isothiocyanate derivatives in 75–88% yield, and their molecular structures were characterized by using 1H/13C NMR, FT-IR and HRMS techniques. Urea-thiourea hybrids have been known for their anti-inflammatory activities. Therefore, in our study, we aimed to decipher their biological activities on mammalian macrophages. Macrophages were stimulated by LPS and pro-inflammatory TNF, IL6, GMCSF and IL12p40 cytokine production levels were measured in the presence of these derivatives by ELISA. Our results suggest that these derivatives on stimulated mammalian macrophages had anti-inflammatory activities. In order to examine their intracellular mechanism of action, intracellular phosphorylated (activated) PI3K protein levels were measured in the presence of our novel derivatives by flow cytometry. Our results suggest that these novel derivatives had anti-inflammatory activities on mammalian macrophages by blocking the PI3K activation and decreasing the production of pro-inflammatory cytokines. Molecular docking calculations were also employed to elucidate the theoretical binding modes of our studied compounds with PI3Kγ. These derivatives have the potential to be utilized as anti-inflammatory drug agents against versatile inflammatory and autoimmune disorders.