Inflammatory Immune Cells Research Articles

Dual Function of Secreted APE1/Ref-1 in TNBC Tumorigenesis: An Apoptotic Initiator and a Regulator of Chronic Inflammatory Signaling.

The simultaneous regulation of cancer cells and inflammatory immune cells in the tumor microenvironment (TME) can be an effective strategy in treating aggressive breast cancer types, such as triple-negative breast cancer (TNBC). Apurinic/apyrimidinic endonuclease 1/redox effector factor 1 (APE1/Ref-1) is a multi-functional nuclear protein that can be stimulated and then secreted. The extracellular APE1/Ref-1 causes a reduction in disulfide bonds in cytokine receptors, resulting in their conformational changes, thereby inhibiting inflammatory signaling. Furthermore, the secreted APE1/Ref-1 in response to acetylation has been shown to bind to a receptor for the advanced glycation end product (RAGE), initiating the apoptotic cell death of TNBC in vitro and in vivo. This study used PPTLS-APE1/Ref-1 in an adenovirus vector (Ad-PPTLS-APE1/Ref-1) for the constant expression of extracellular APE1/Ref-1, and our results demonstrated its dual function as an apoptotic initiator and inflammation regulator. Injecting MDA-MB 231 orthotopic xenografts with the Ad-PPTLS-APE1/Ref-1 inhibited tumor growth and development in response to acetylation. Moreover, Ad-PPTLS-APE1/Ref-1 generated reactive oxygen species (ROS), and tumor tissues derived from these xenografts exhibited apoptotic bodies. Compared to normal mice, a comparable ratio of anti- and pro-inflammatory cytokines was observed in the plasma of Ad-PPTLS-APE1/Ref-1-injected mice. Mechanistically, the disturbed cytokine receptor by reducing activity of PPTLS-APE1/Ref-1 inhibited inflammatory signaling leading to the inactivation of the p21-activated kinase 1-mediated signal transducer and activator of transcription 3/nuclear factor-κB axis in tumor tissues. These results suggest that the regulation of inflammatory signaling with adenoviral-mediated PPTLS-APE1/Ref-1 in tumors modulates the secretion of pro-inflammatory cytokines in TME, thereby inhibiting aggressive cancer cell progression, and could be considered as a promising and safe therapeutic strategy for treating TNBCs.

Interleukin-18 cytokine in immunity, inflammation, and autoimmunity: Biological role in induction, regulation, and treatment.

Interleukin-18 (IL-18) is a potent pro-inflammatory cytokine involved in host defense against infections and regulates the innate and acquired immune response. IL-18 is produced by both hematopoietic and non-hematopoietic cells, including monocytes, macrophages, keratinocytes and mesenchymal cell. IL-18 could potentially induce inflammatory and cytotoxic immune cell activities leading to autoimmunity. Its elevated levels have been reported in the blood of patients with some immune-related diseases, including rheumatoid arthritis, systemic lupus erythematosus, type I diabetes mellitus, atopic dermatitis, psoriasis, and inflammatory bowel disease. In the present review, we aimed to summarize the biological properties of IL-18 and its pathological role in different autoimmune diseases. We also reported some monoclonal antibodies and drugs targeting IL-18. Most of these monoclonal antibodies and drugs have only produced partial effectiveness or complete ineffectiveness in vitro, in vivo and human studies. The ineffectiveness of these drugs targeting IL-18 may be largely due to the loophole caused by the involvement of other cytokines and proteins in the signaling pathway of many inflammatory diseases besides the involvement of IL-18. Combination drug therapies, that focus on IL-18 inhibition, in addition to other cytokines, are highly recommended to be considered as an important area of research that needs to be explored.

Long-term implications of COVID-19 on bone health: pathophysiology and therapeutics.

BackgroundSARS-CoV-2 is a highly infectious respiratory virus associated with coronavirus disease (COVID-19). Discoveries in the field revealed that inflammatory conditions exert a negative impact on bone metabolism; however, only limited studies reported the consequences of SARS-CoV-2 infection on skeletal homeostasis. Inflammatory immune cells (T helper—Th17 cells and macrophages) and their signature cytokines such as interleukin (IL)-6, IL-17, and tumor necrosis factor-alpha (TNF-α) are the major contributors to the cytokine storm observed in COVID-19 disease. Our group along with others has proven that an enhanced population of both inflammatory innate (Dendritic cells—DCs, macrophages, etc.) and adaptive (Th1, Th17, etc.) immune cells, along with their signature cytokines (IL-17, TNF-α, IFN-γ, IL-6, etc.), are associated with various inflammatory bone loss conditions. Moreover, several pieces of evidence suggest that SARS-CoV-2 infects various organs of the body via angiotensin-converting enzyme 2 (ACE2) receptors including bone cells (osteoblasts—OBs and osteoclasts—OCs). This evidence thus clearly highlights both the direct and indirect impact of SARS-CoV-2 on the physiological bone remodeling process. Moreover, data from the previous SARS-CoV outbreak in 2002–2004 revealed the long-term negative impact (decreased bone mineral density—BMDs) of these infections on bone health.MethodologyWe used the keywords “immunopathogenesis of SARS-CoV-2,” “SARS-CoV-2 and bone cells,” “factors influencing bone health and COVID-19,” “GUT microbiota,” and “COVID-19 and Bone health” to integrate the topics for making this review article by searching the following electronic databases: PubMed, Google Scholar, and Scopus.ConclusionCurrent evidence and reports indicate the direct relation between SARS-CoV-2 infection and bone health and thus warrant future research in this field. It would be imperative to assess the post-COVID-19 fracture risk of SARS-CoV-2-infected individuals by simultaneously monitoring them for bone metabolism/biochemical markers. Importantly, several emerging research suggest that dysbiosis of the gut microbiota—GM (established role in inflammatory bone loss conditions) is further involved in the severity of COVID-19 disease. In the present review, we thus also highlight the importance of dietary interventions including probiotics (modulating dysbiotic GM) as an adjunct therapeutic alternative in the treatment and management of long-term consequences of COVID-19 on bone health.

Comprehensive Network Analysis Reveals the Targets and Potential Multitarget Drugs of Type 2 Diabetes Mellitus.

Type 2 diabetes mellitus (T2DM) is a metabolic disease with increasing prevalence and mortality year by year. The purpose of this study was to explore new therapeutic targets and candidate drugs for multitargets by single-cell RNA expression profile analysis, network pharmacology, and molecular docking. Single-cell RNA expression profiling of islet β cell samples between T2DM patients and nondiabetic controls was conducted to identify important subpopulations and the marker genes. The potential therapeutic targets of T2DM were identified by the overlap analysis of insulin-related genes and diabetes-related genes, the construction of protein-protein interaction network, and the molecular complex detection (MCODE) algorithm. The network distance method was employed to determine the potential drugs of the target. Molecular docking and molecular dynamic simulations were carried out using AutoDock Vina and Gromacs2019, respectively. Eleven cell clusters were identified by single-cell RNA sequencing (scRNA-seq) data, and three of them (C2, C8, and C10) showed significant differences between T2DM samples and normal samples. Eight genes from differential cell clusters were found from differential cell clusters to be associated with insulin activity and T2DM. The MCODE algorithm built six key subnetworks, with five of them correlating with inflammatory pathways and immune cell infiltration. Importantly, CCR5 was a gene within the key subnetworks and was differentially expressed between normal samples and T2DM samples, with the highest area under the ROC curve (AUC) of 82.5% for the diagnosis model. A total of 49 CCR5-related genes were screened, and DB05494 was identified as the most potential drug with the shortest distance to CCR5-related genes. Molecular docking illustrated that DB05494 stably bound with CCR5 (-8.0 kcal/mol) through multiple hydrogen bonds (LYS26, TYR37, TYR89, CYS178, and GLN280) and hydrophobic bonds (TRP86, PHE112, ILE198, TRP248, and TYR251). This study identified CCR5 as a potential therapeutic target and screened DB05494 as a potential drug for T2DM treatment.

Advances in anti-tumor research based on bionic micro-/nano technology

<p indent="0mm">A malignant tumor is a serious disease that can cause great harm to human health. Currently, the clinical treatment of tumors primarily includes surgery, chemotherapy, and radiotherapy. However, these three methods can cause significant damage to patient health and are expensive, causing considerable financial duress to patients. Thus, there is a pressing need to determine safe, effective, and low-cost treatments for cancer. One of the primary reasons malignant tumors are difficult to treat is that tumor cells constantly adapt to their environment, thereby forming a suitable tumor microenvironment (TME) that supports their growth. The TME is composed of immune cells, inflammatory cells, cancer-associated fibroblasts, capillaries, and various cytokines and chemokines, thus forming a complex integrated system. As the living environment of tumor cells, it is closely related to tumor genesis, metastasis, and recurrence. It is believed that the TME is not a silent spectator but an active promoter of cancer progression. Compared with normal cells, tumor cells show a lack of oxygen, a weakly acidic environment, and physiological phenotypes that directly result in the lack of oxygen. Oxygen-dependent X-ray radiotherapy, chemical therapy, and photodynamic therapy; tumor cells also indirectly affect cell metabolism and largely reduce the toxicity of some drugs, thus greatly enhancing genetic instability. TME provides conditions for the rapid growth and evolution of tumor cells so that tumor cells develop strong drug resistance. Although physiological phenotypes, such as tumor hypoxia and weakly acidic microenvironment, affect the clinical efficacy of tumors to a certain extent, they also provide therapeutic targets and research entry points for new tumor diagnosis and treatment strategies. With the advances in bionics, molecular sciences, gene technology, and nanoscience, the bionic micro-nano fusion tumor therapy has become a research hotspot. Bionic treatment has opened new avenues for patients with malignant tumors owing to its good biocompatibility and is receiving increasing attention from researchers. This environmentally friendly, efficient, long-term, and low-cost treatment method has good clinical application prospects and is becoming an effective means of antitumor treatment. Researchers have drawn inspiration from nature to develop and design biomimetic antitumor materials with excellent biocompatibility compared with traditional medicine, stronger antitumor effect, and lower cost. From the perspective of improving the TME, this paper describes the advantages of four types of tumor biomimetic treatment materials, analyzes the therapeutic effects of each material, summarizes the problems faced in their commercial use, and prospects the future applications of these materials.

Hub Genes Identification, Small Molecule Compounds Prediction for Atrial Fibrillation and Diagnostic Model Construction Based on XGBoost Algorithm.

BackgroundAtrial fibrillation (AF) is the most common sustained cardiac arrhythmia and engenders significant global health care burden. The underlying mechanisms of AF is remained to be revealed and current treatment options for AF have limitations. Besides, a detection system can help identify those at risk of developing AF and will enable personalized management.Materials and MethodsIn this study, we utilized the robust rank aggregation method to integrate six AF microarray datasets from the Gene Expression Omnibus database, and identified a set of differentially expressed genes between patients with AF and controls. Potential compounds were identified by mining the Connectivity Map database. Functional modules and closely-interacted clusters were identified using weighted gene co-expression network analysis and protein–protein interaction network, respectively. The overlapped hub genes were further filtered. Subsequent analyses were performed to analyze the function, biological features, and regulatory networks. Moreover, a reliable Machine Learning-based diagnostic model was constructed and visualized to clarify the diagnostic features of these genes.ResultsA total of 156 upregulated and 34 downregulated genes were identified, some of which had not been previously investigated. We showed that mitogen-activated protein kinase and epidermal growth factor receptor inhibitors were likely to mitigate AF based on Connectivity Map analysis. Four genes, including CXCL12, LTBP1, LOXL1, and IGFBP3, were identified as hub genes. CXCL12 was shown to play an important role in regulation of local inflammatory response and immune cell infiltration. Regulation of CXCL12 expression in AF was analyzed by constructing a transcription factor-miRNA-mRNA network. The Machine Learning-based diagnostic model generated in this study showed good efficacy and reliability.ConclusionKey genes involving in the pathogenesis of AF and potential therapeutic compounds for AF were identified. The biological features of CXCL12 in AF were investigated using integrative bioinformatics tools. The results suggested that CXCL12 might be a biomarker that could be used for distinguishing subsets of AF, and indicated that CXCL12 might be an important intermediate in the development of AF. A reliable Machine Learning-based diagnostic model was constructed. Our work improved understanding of the mechanisms of AF predisposition and progression, and identified potential therapeutic avenues for treatment of AF.

Linking inflammatory adipose tissue to placental abnormalities in obese preeclamptic pregnancies.

Preeclampsia (PE), a pregnancy-specific disorder, is characterized by maternal hypertension and proteinuria or another accompanying sign/symptom of multiorgan dysfunction. Maternal symptoms resolve with delivery of the baby and, importantly, the placenta. Therefore, the placenta plays a causal role in PE. However, the precise cause of abnormal placental development and/or function is unknown. Women with obesity have an increased risk of developing PE that is potentially related to the increased inflammation that accompanies increased maternal adiposity. Furthermore, inflammatory adipokines, i.e., leptin, have been linked to the development of systemic inflammation, hypertension, and other adverse outcomes associated with PE. Rodent models that recapitulate key pathophysiological features of the maternal and fetal syndrome have been used translationally to study PE. This review covers inflammatory adipokines, immune cells, and impaired placental development associated with PE in women and in rodent models of PE that use functional genomics to test causation.

The protective effect of MiR-27a on the neonatal hypoxic-ischemic encephalopathy by targeting FOXO1 in rats.

BackgroundNeonatal hypoxic-ischemic encephalopathy (HIE), a kind of hypoxic-ischemic brain damage caused by perinatal asphyxia, is the most crucial cause of neonatal death and long-term neurological dysfunction in children. We aimed to investigate the protective effects of micro (mi)R-27a on HIE in neonatal rats.MethodsA rat model of neonatal HIE was constructed by modification of the Rice-Vannucci model. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to test the expressions of miR-27a, FOXO1 messenger RNA (mRNA), interleukin-1β (IL-1β) mRNA, and tumor necrosis factor-α (TNF-α) mRNA, and western blot was applied to test the expression of FOXO1. In order to overexpress miR-27a, an intracerebroventricular injection (i.c.v) of miR-27a mimic was administered. We adopted 2,3,5-triphenytetrazolium chloride (TTC) staining and brain water content measurement to test the effects of miR-27a on the infarcted volume and edema in brain after HIE. Flow cytometry (FCM) analysis was applied to test the effects of miR-27a on the infiltrated peripheral immune cells in the rat brains after HIE.ResultsWe successfully established a rat model of neonatal HIE. It was revealed that the expressions of miR-27a decreased gradually after HIE, however, the expressions of FOXO1 mRNA increased. After injection of the miR-27a mimic, the expression of miR-27a in the rat HIE model brains was significantly upregulated, however, the expression of FOXO1 was robustly downregulated. Both TTC staining and brain water content showed that the infarcted volume and brain edema was markedly increased after HIE. Interestingly, the overexpression of miR-27a reduced the infarcted volume and edema induced by HIE. Additionally, RT-qPCR and FCM analysis showed that HIE lead to increases of IL-1β, TNF-α, and infiltrated immune cells. Overexpression of miR-27a could reduce the expressions of IL-1β mRNA and TNF-α mRNA, and the cell numbers of infiltrated peripheral macrophages and neutrophils in the brain.ConclusionsMiR-27a plays protective roles by reducing infarct volume and brain edema, and inhibiting inflammatory factors and infiltrated peripheral immune cells by targeting FOXO1 in neonatal HIE rats.

4-Ethylguaiacol Modulates Neuroinflammation and Promotes Heme Oxygenase-1 Expression to Ameliorate Brain Injury in Ischemic Stroke.

Ischemic stroke is caused by a sudden reduction in cerebral blood flow that subsequently induces a complex cascade of pathophysiological responses, leading to brain inflammation and irreversible infarction. 4-ethylguaiacol (4-EG) is reported to suppress inflammatory immune responses. However, whether 4-EG exerts anti-inflammatory effects in ischemic stroke remains unexplored. We evaluated the therapeutic potential of 4-EG and examined the cellular and molecular mechanisms underlying the protective effects of 4-EG in ischemic stroke. The effect of 4-EG in ischemic stroke was determined by using a transient middle cerebral artery occlusion (MCAO) animal model followed by exploring the infarct size, neurological deficits, microglia activation, inflammatory cytokine production, blood–brain barrier (BBB) disruption, brain endothelial cell adhesion molecule expression, and microglial heme oxygenase-1 (HO-1) expression. Nrf2-/- and HO-1 inhibitor ZnPP-treated mice were also subjected to MCAO to evaluate the role of the Nrf2/HO-1 pathway in 4-EG-mediated protection in ischemic stroke. We found that 4-EG attenuated infarct size and neurological deficits, and lessened BBB disruption in ischemic stroke. Further investigation revealed that 4-EG suppressed microglial activation, peripheral inflammatory immune cell infiltration, and brain endothelial cell adhesion molecule upregulation in the ischemic brain. Finally, we identified that the protective effect of 4-EG in ischemic stroke was abolished in Nrf2-/– and ZnPP-treated MCAO mice. Our results identified that 4-EG confers protection against ischemic stroke and reveal that the protective effect of 4-EG in ischemic stroke is mediated through the induction of the Nrf2/HO1 pathway. Thus, our findings suggest that 4-EG could be developed as a novel therapeutic agent for the treatment of ischemic stroke.

Dendritic Cells and Macrophages in the Pathogenesis of Psoriasis.

Psoriasis is a chronic inflammatory skin disease characterized by scaly indurated erythema. This disease impairs patients’ quality of life enormously. Pathological findings demonstrate proliferation and abnormal differentiation of keratinocytes and massive infiltration of inflammatory immune cells. The pathogenesis of psoriasis is complicated. Among immune cells, dendritic cells play a pivotal role in the development of psoriasis in both the initiation and the maintenance phases. In addition, it has been indicated that macrophages contribute to the pathogenesis of psoriasis especially in the initiation phase, although studies on macrophages are limited. In this article, we review the roles of dendritic cells and macrophages in the pathogenesis of psoriasis.

Negative Associations of Stress and Anxiety Levels With Cytotoxic and Regulatory Natural Killer Cell Frequency in Chronic Tinnitus.

BackgroundDepression and anxiety are known to be associated with stress-induced changes in the immune system. Bothersome tinnitus can be related to stress and often co-occurs with depression and anxiety. This study investigates associations of psychological and audiological tinnitus-related factors with inflammatory parameters and immune cell subsets in chronic tinnitus patients as well as treatment-related effects.MethodsThis longitudinal study of inpatients treated with compact multimodal tinnitus-specific cognitive behavioral therapy included four repeated measurement sessions: baseline (N = 41), treatment end, 7.8-week (N = 35), and 13.8-week follow-up (N = 34). Data collection included audiometric testing, blood sampling, and psychometric questionnaires: Tinnitus Handicap Inventory (THI), Perceived Stress Questionnaire (PSQ-20), and Hospital Anxiety Depression Scale (HADS). Flow cytometry was used to analyze immune cell subsets. Statistical analyses comprised correlation and network analysis (cross-sectional), and linear mixed effect models (longitudinal).ResultsBootstrapped network analysis showed negative averaged cross-sectional associations of cytotoxic natural killer (NKc) cell frequency (CD56 + CD16+) and PSQ-20 (−0.21 [−0.48, 0]) and of regulatory natural killer (NKreg) cell frequency (CD56 + CD16dim/−) and HADS anxiety (−0.14 [−0.38, 0]). No significant treatment effects were found. A negative predictive effect of baseline PSQ-20 scores (β = −6.22 [−12.18, −0.26], p = 0.041) and a positive predictive effect of baseline ferritin levels (β = 8.90 [2.76, 15.03], p = 0.004) on NKc cell frequency across the repeated measurement sessions were observed.ConclusionWe observed negative relationships between perceived stress levels and NKc cell frequency and between anxiety levels and NKreg cell frequency in chronic tinnitus patients. These exploratory results suggest stress−/anxiety-related immune alterations in bothersome tinnitus but need to be tested in further confirmatory studies with larger sample sizes. The potential of NK cells as biomarkers of emotional distress in chronic tinnitus should be further investigated.

CircDCLRE1C Regulated Lipopolysaccharide-Induced Inflammatory Response and Apoptosis by Regulating miR-214b-3p/STAT3 Pathway in Macrophages.

The immune cell inflammation response is closely related to the occurrence of disease, and much evidence has shown that circular RNAs (circRNAs) play vital roles in the occurrence of disease. However, the biological function and regulatory mechanisms of circRNAs in the immune cell inflammation response remain poorly understood. In this study, we constructed an inflammatory model using lipopolysaccharide (LPS)-stimulated chicken macrophage lines (also known as HD11) to verify the function and mechanism of the novel circDCLRE1C (ID: gga_circ_0001674), which was significantly upregulated in spleen tissues infected by coccidia and the macrophage cells exposed to LPS. The results showed that circDCLRE1C aggravated LPS-induced inflammation and apoptosis in HD11 cells. Systemically, circDCLRE1C acted as a sponge for miR-214b-3p binding sites thereby regulating the expression of STAT3. The overexpression of miR-214b-3p rescued the pro-inflammatory effect of circDCLRE1C in HD11 cells stimulated with LPS, and rescued the high expression of STAT3. In conclusion, our study showed that circDCLRE1C could aggravate LPS-induced inflammation and apoptosis through competitive adsorption of miR-214b-3p, thereby increasing the expression of STAT3.

Abstract 5273: The peripheral proinflammatory responses in COVID-19: Clinical spectrum and outcome in patients with and without cancer

Abstract Background: A meta-analysis of COVID-19 shows that the pooled prevalence of cancer is 1.4%. Febrile illness during COVID-19 is caused by cytokine release syndrome energized by innate inflammatory immune cells, neutrophils, monocytes, and macrophages. Cancer has a worse clinical outcome with COVID-19 due to a potential contribution of the disordered inflammatory microenvironment and immune system. This study aimed to determine the impact of peripheral inflammatory responses on clinical outcome and severity of COVID-19 patients with and without cancer and compare their clinical spectra. Methodology: This IRB-approved, retrospective chart review performed at PNOC included patients 18 years or older with PCR-confirmed COVID-19 from April 2020 to April 2021. Histopathology-confirmed cases identified excluded cranial metastases, pregnancy, or ICU-ineligible due to advanced malignancy or missing data. We collected the first clinical encounter data following a positive COVID-19 test, including CDC-defined COVID-19 symptoms, co-morbidities, cancer status, and treatment—clinical outcomes and death from any cause within30 days of COVID-19 diagnosis. We determined peripheral blood inflammatory cells of neutrophils, lymphocytes, monocytes, platelets and the ratios between lymphocytes and the other three. According to INH guidelines, we ranked clinical severity as presymptomatic, mild, moderate, severe, or critical. Results: Of 3745 people with PCR-confirmed COVID-19, 65 (1.7%) had cancer. We randomly selected 130 non-cancer subjects, homogeneously distributed across each month. The median age was 59 years. Of all, 52.3% were women, 43% were diabetic, 45% were hypertensive, and 35% had the cardiopulmonary disease. Dyspnea occurs in 30.8% of those with cancer but in 59.2% of those without cancer (P &amp;lt; .001). High neutrophil was significantly associated with severity (P = .038), but there was no significant difference between cancer and non-cancer groups. High lymphocytes, MPV, and Neutrophil/Lymphocyte ratio were associated with symptoms but not outcome or severity. Death from any cause was more in the group with cancer 23.1% vs. 6.9%, P= .001. Only 2% of study participants with cancer continued chemotherapy after the diagnosis of COVID-19 was confirmed. Conclusion: Mortality significantly remains higher when cancer is comorbid with COVID-19, as seen in international groups. Further studies are needed to confirm whether cancer immunomodulation is a factor. Peripheral inflammatory response modestly predicts a worse outcome, particularly with elevated neutrophils, known for its proinflammatory rule by polarization and neutrophil extracellular trap (NET) formation with platelet activation. There was a modest increase in symptoms severity in non-cancer COVID19 but more mortality in cancer comorbid COVID-19 Citation Format: Amer N. Radwi, Zahra H. Alshardi, Rakan H. Alelyani, Raha M. Garout, Lojain N. Alruwaili, Muhammad T. Bakhsh. The peripheral proinflammatory responses in COVID-19: Clinical spectrum and outcome in patients with and without cancer [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 5273.

Abstract 5631: Immunomodulatory activity of sulindac plus erlotinib for colon cancer prevention in familial adenomatous polyposis

Abstract Familial adenomatous polyposis (FAP) is an autosomal dominant disorder caused by germline mutation in Adenomatous Polyposis Coli (APC)1. Patients with FAP have a nearly 100% lifetime risk of colorectal cancer (CRC) due to the formation of hundreds to thousands of adenomatous polyps in the gastrointestinal tract2. A clinical trial in FAP patients demonstrated that Cox-1/2 inhibitor sulindac (SUL) plus EGFR inhibitor erlotinib (ERL) reduced polyp burden significantly in the colon and small intestine (SI), but toxicity issues raised concerns for durable long-term CRC interception3. In the Apc-mutant polyposis in rat colon (Pirc) rat model of FAP, we determined low-dose regimens of ERL+SUL that were both safe and efficacious4. In the current investigation, the lowest tested dose of dietary SUL (125 ppm continuously) plus ERL (5 mg/kg twice weekly), given at one-half the SUL clinical dose and one-fourth of the ERL clinical dose, administered for 46 weeks respectively, demonstrated good inhibition of tumor burden in the colon (&amp;gt;85% efficacy, p&amp;lt;0.05) and SI (&amp;gt;94% efficacy, p&amp;lt;0.05) compared to untreated controls. Moreover, treatment normalized organ weights and hematocrits that were altered in the untreated AIN controls.Recently, ERL5 and SUL6 were individually demonstrated to increase the recruitment of inflammatory immune cells in mouse models of lung and colon cancer, respectively. However, ERL+SUL in combination was not investigated in the context of immune cell infiltration and polarization. Our preliminary IHC data in the Pirc model indicated increased recruitment of CD8+ T cells in colon polyps by SUL 250 ppm + ERL 42 mg/kg once a week. RT-qPCR and immunoblotting analysis of colon polyps obtained from the low-dose combination of SUL 125 ppm + ERL 5 mg/kg twice weekly demonstrated increased CD4 expression and concurrently decreased oncogenic IL-17 expression and tumor associated macrophage markers (CD163 and CD206) (P&amp;lt;0.05 vs control). Additional immune markers will be identified and validated via CyTOF. We hypothesize that low-dose combination of SUL+ERL can enhance the recruitment of immune cells into early adenomatous colon and SI polyps, providing an effective immunointerception strategy, with potential clinical relevance for FAP patients before or after colectomy. Acknowledgements Research supported by NCI Contract Number 75N91019D00021, Task Order 75N91019F00130. 1.Groden J et al., Cell 1991; 66:589-600.2.Jasperson KW et al., Gastroenterology 2010; 138:2044-2058.3.Samadder NJ et. al., JAMA 2016; 315:1266-75.4.Ulusan AM et. al., Cancer Prev Res (Phila). 2021; 14:325-336.5.Ayeni D et al., J Immunother Cancer 2019; 7:172.6.Yi B et al., Mol Cancer Ther 2021; Apr 20. Citation Format: Chakrapani Tripathi, Roderick H. Dashwood. Immunomodulatory activity of sulindac plus erlotinib for colon cancer prevention in familial adenomatous polyposis [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 5631.

Mesenchymal Stem Cells Attenuate Acute Lung Injury in Mice Partly by Suppressing Alveolar Macrophage Activation in a PGE2-Dependent Manner.

Mesenchymal stem cells (MSCs) have been demonstrated to attenuate acute lung injury (ALI). We also found that they can suppress the activation of alveolar macrophages (AMs), which can partly account for their therapeutic effects. MSCs do not inherently own immunosuppressive effects, when co-cultured with inflammatory immune cells, MSCs can be activated by inflammatory cytokines and meanwhile exert immunosuppressive effects. In order to further research, RNA sequencing (RNA-seq) of MSCs cultured before and after co-culturing with activated macrophages was performed. The data suggested a total of 5268 differentially expressed genes (DEGs) along the process. We used the data of 2754 upregulated DEGs to develop a signaling network of genes and the transcription factors targeting them in order to predict the altered functions of MSCs after exposure to inflammatory stimuli. This constructed network revealed some critical target genes and potential roles of MSCs under inflammatory conditions. According to the network, Ptgs2 was assumed to be an important gene participating in the immunosuppressive effects of MSCs. We also identified significant increases in the expression of COX2 protein and the secretion of PGE2 from MSCs. The use of the COX2 inhibitor NS-398 restrained the secretion of PGE2 and reversed the suppression of macrophage activation by MSCs in vitro. In addition, a selective antagonist of PGE2 binding receptor (EP4 receptor), GW627368X, also reversed the inhibitory effects of MSCs on AMs and the protective effects in ALI mouse. In summary, the therapeutic effects of MSCs on ALI partly occur through suppressing AM activation via PGE2 binding to EP4 receptor.

Microbial-Derived Toll-like Receptor Agonism in Cancer Treatment and Progression

Simple SummaryToll like receptors (TLRs) are a group of transmembrane receptors belonging to the class of pattern recognition receptors (PRR), which are involved in recognition of pathogen associated molecular patterns (PAMPs), inducing immune response. During the past decade, a number of preclinical and clinical breakthroughs in the field of TLR agonists has immerged in cancer research and some of these agents have performed exceptionally well in clinical trials. Based on evidence from scientific studies, we draw attention to several microbial based TLR agonists and discuss their relevance in various cancer and explore various microbial based TLR agonists for developing effective immunotherapeutic strategies against cancer.Toll-like receptors (TLRs) are typical transmembrane proteins, which are essential pattern recognition receptors in mediating the effects of innate immunity. TLRs recognize structurally conserved molecules derived from microbes and damage-associated molecular pattern molecules that play an important role in inflammation. Since the first discovery of the Toll receptor by the team of J. Hoffmann in 1996, in Drosophila melanogaster, numerous TLRs have been identified across a wide range of invertebrate and vertebrate species. TLR stimulation leads to NF-κB activation and the subsequent production of pro-inflammatory cytokines and chemokines, growth factors and anti-apoptotic proteins. The expression of TLRs has also been observed in many tumors, and their stimulation results in tumor progression or regression, depending on the TLR and tumor type. The anti-tumoral effects can result from the activation of anti-tumoral immune responses and/or the direct induction of tumor cell death. The pro-tumoral effects may be due to inducing tumor cell survival and proliferation or by acting on suppressive or inflammatory immune cells in the tumor microenvironment. The aim of this review is to draw attention to the effects of TLR stimulation in cancer, the activation of various TLRs by microbes in different types of tumors, and, finally, the role of TLRs in anti-cancer immunity and tumor rejection.

A Novel Enolase-1 Antibody Targets Multiple Interacting Players in the Tumor Microenvironment of Advanced Prostate Cancer.

Prostate cancer is one of the most common causes of cancer death in men worldwide, and the treatment options are limited for patients with advanced stages of prostate cancer. Upon oncogenic or inflammatory stimulation, tumor cells or immune cells express cell surface enolase-1 (ENO1) as plasminogen receptor to facilitate their migration via plasmin activation. Little is known about the roles of ENO1 in prostate cancer, especially in the tumor microenvironment (TME). We hypothesized that targeting surface ENO1 with specific mAbs would exert multifactorial therapeutic potentials against prostate cancer. In vivo, we showed ENO1 mAb (HuL227) reduced the growth of subcutaneous PC-3 xenograft, monocytes recruitment, and intratumoral angiogenesis. In a PC-3 intratibial implantation model, HuL227 reduced tumor growth and osteoclast activation in the bone. To investigate the antitumor mechanism of ENO1 mAb, we found that blocking surface ENO1 significantly reduced VEGF-A-induced tube formation of endothelial cells in vitro. Furthermore, HuL227 inhibited inflammation-enhanced osteoclasts activity and the secretion of invasion-related cytokines CCL2 and TGFβ from osteoclasts. In addition, inflammation-induced migration and chemotaxis of androgen-independent prostate cancer cells were dose-dependently inhibited by HuL227. In summary, we showed that, ENO1 mAb targets multiple TME niches involved in prostate cancer progression and bone metastasis via a plasmin-related mechanism, which may provide a novel immunotherapy approach for men with advanced prostate cancer.

Evaluation of the Cytotoxic, Anti-Inflammatory, and Immunomodulatory Effects of Withaferin A (WA) against Lipopolysaccharide (LPS)-Induced Inflammation in Immune Cells Derived from BALB/c Mice.

(1) Background: Inflammation is one of the primary responses of the immune system and plays a key role in the pathophysiology of various diseases. Recent reports suggest that various phytochemicals exhibit promising anti-inflammatory and immunomodulation activities with relatively few undesirable effects, thus offering a viable option to deal with inflammation and associated diseases. The current study evaluates the anti-inflammatory and immunomodulatory effects of withaferin A (WA) in immune cells extracted from BALB/c mice. (2) Methods: MTT assays were performed to assess the cell viability of splenocytes and anti-inflammatory doses of WA. Under aseptic conditions, the isolation of macrophages and splenocytes from BALB/c mice was performed to investigate the anti-inflammatory effects of WA. Analysis of the expression of proinflammatory cytokines and associated signaling mediators was performed using proinflammatory assay kits, real-time polymerase chain reaction (RT-PCR), and immunoblotting, while the quantification of B and T cells was performed by flow cytometry. (3) Results: Our results demonstrated that WA exhibits anti-inflammatory and immunomodulatory effects in LPS-stimulated macrophages and splenocytes derived from BALB/c mice, respectively. Mechanistically, we found that WA promotes an anti-inflammatory effect on LPS-stimulated macrophages by attenuating the secretion and expression of proinflammatory cytokines TNF-α, IL-1β, IL-6, and the inflammation modulator NO, both at the transcriptional and translational level, respectively. Further, WA inhibits LPS-stimulated inflammatory signaling by dephosphorylation of p-Akt-Ser473 and p-ERK1/2. This dephosphorylation does not allow IĸB-kinase activation to disrupt IĸB–NF-ĸB interaction. The consistent interaction of IĸB with NF-ĸB in WA-treated cells attenuates the activation of downstream inflammatory signaling mediators Cox-2 and iNOS expression, which play crucial roles in inflammatory signaling. Additionally, we observed significant immunomodulation of LPS-stimulated spleen-derived lymphocytes by suppression of B (CD19) and T (CD4+/CD8+) cell populations after treatment with WA. (4) Conclusion: WA exhibits anti-inflammatory and immunomodulatory activity by modulating Akt/ERK/NF-kB-mediated inflammatory signaling in macrophages and immunosuppression of B (CD19) and T cell (CD4+/CD8+) populations in splenocytes after LPS stimulation. These results suggest that WA could act as a potential anti-inflammatory/immunomodulatory molecule and support its use in the field of immunopharmacology to modulate immune system cells.

Transcriptomic Profiling Reveals That HMGB1 Induces Macrophage Polarization Different from Classical M1.

Macrophages are key inflammatory immune cells that display dynamic phenotypes and functions in response to their local microenvironment. In different conditions, macrophage polarization can be induced by high-mobility group box 1 (HMGB1), a nuclear DNA-binding protein that activates innate immunity via the Toll-like receptor (TLR) 4, the receptor for advanced glycation end products (RAGE), and C-X-C chemokine receptor (CXCR) 4. This study investigated the phenotypes of murine bone-marrow-derived macrophages (BMDMs) stimulated with different HMGB1 redox isoforms using bulk RNA sequencing (RNA-Seq). Disulfide HMGB1 (dsHMGB1)-stimulated BMDMs showed a similar but distinct transcriptomic profile to LPS/IFNγ- and LPS-stimulated BMDMs. Fully reduced HMGB1 (frHMGB1) did not induce any significant transcriptomic change. Interestingly, compared to LPS/IFNγ- and LPS-, dsHMGB1-stimulated BMDMs showed lipid metabolism and foam cell differentiation gene set enrichment, and oil red O staining revealed that both dsHMGB1 and frHMGB1 alleviated oxidized low-density lipoprotein (oxLDL)-induced foam cells formation. Overall, this work, for the first time, used transcriptomic analysis by RNA-Seq to investigate the impact of HMGB1 stimulation on BMDM polarization. Our results demonstrated that dsHMGB1 and frHMGB1 induced distinct BMDM polarization phenotypes compared to LPS/IFNγ- and LPS- induced phenotypes.

78-OR: LRH-1/NR5A2 Agonism Triggers an Anti-Inflammatory Phenotypic Switch of Immune Cells from Patients with Type 1 Diabetes and Improves Islet Engraftment/Function

Administration of the LRH-1 agonist BL0refrains hyperglycemia in 3 mouse models of type 1 diabetes (T1DM) . This antidiabetes action correlated with beta cell mass preservation and the presence of anti, rather than pro, inflammatory immune cells, indicating tolerization. Herein, we sought to translate these data to human immune cells of T1DM patients to demonstrate BL0benefits to re-educate the immune system and to assess its therapeutic value on human islet engraftment/function. Blood mononuclear cells purified from blood samples (healthy and T1DM) were derived in culture into 1) pro-inflammatory macrophages (MDM1) , 2) mature dendritic cells (mDCs) , 3) T-cells and 4) B-cells. Cells were then treated with BL0 and processed for 1) cell surface marker profiling, 2) cytokine secretome profiling, 3) T-cell proliferation and 4) RNAseq. In T1DM samples, BL0reduced the expression of pro-inflammatory markers on MDM1 (CD80) and mDCs (CD54 and CXCR4) and the secretion of the pro-inflammatory cytokines, CXCL6 and CCL24 (MDM1) as well as IL7 (mDCs) . Moreover, in these samples, BL0also increased Tregs, but not B-cells. T-cell proliferation was blunted by BL001-treated mDCs and Tregs. RNAseq analysis of BL001-treated MDM1 revealed increased expression of genes encoding components of complex I, III, IV, and V of the respiratory chain consistent with a transition from a glycolytic driven MDM1 to an oxidative phosphorylation driven MDM2 anti-inflammatory phenotype. BL0administration to STZ-treated mice transplanted with human islet improved survival correlating with reduced hyperglycemia, increased circulating human C-peptide, preserved beta cell mass, and reduced CD4+ T-cell infiltration. Our results establish that BL0can induce a pro-to-anti-inflammatory phenotypic switch to human immune cells, and improve human islet engraftment/function, supporting the therapeutic benefits of BL0in human. Disclosure N. Cobo-Vuilleumier: None. S. Rodriguez-Fernandez: Employee; Ahead Therapeutics SL. P.I. Lorenzo: None. A. Dorronsoro: None. C.C. Lachaud: None. L. Almenara-Fuentes: Employee; Ahead Therapeutics SL. M. Ramos-Rodríguez: None. I. Merida: None. M. Aguilar-Diosdado: None. L. Piemonti: None. L. Pasquali: None. F. Martin: None. I. Garcia-Sanchez: None. M. Martinez-Brocca: None. M. Vives-Pi: Research Support; Ahead Therapeutics S.L. B.R. Gauthier: None. Funding JDRF (2-SRA-2019-837-S-B) Consejeria de Salud y Familia, junta de Andalucia (PI-0001-2020)