bluuebunny/crossref_metadata_2025_split huggingface dataset:
TLR2 dependent enhancement of bacterial clearance in macrophages via TNFR2
Authors: Luu Abby , Hatton Alexis , Shepardson Kelly , Benson Evelyn , Hall Monica , Rynda-Apple Agnieszka 
Published: August 2023

Abstract
The public health crisis of antimicrobial resistance is especially challenging due to the rapid pace of bacterial adaptation to antibiotics. Thus, development of alternatives to antibiotic-based therapies are crucial. We found that stimulation of murine macrophage TLR2/6 heterodimer with Pam2CSK4 (PAM2), a synthetic bacterial lipoprotein, enhanced clearance of subsequent Staphylococcus aureus infection. Whole lung RNA sequencing identified tumor necrosis factor receptor superfamily member 1B (TNFRSF1B, TNFR2) and its cognate cytokine, TNFα, to be upregulated in response to PAM2. ELISA and qPCR data showed both bioactive forms of TNFα, transmembrane (tmTNFα) and soluble (sTNFα), to be upregulated. To mechanistically address the role that TNFR2 could play in PAM2 induced enhanced bacterial clearance (EBC) ability, antibody blocking of TNFR2 led to reduced macrophage S. aureus clearance. In contrast, sTNFα reduction by small molecule inhibition of ADAM17, the enzyme that cleaves tmTNFα to sTNFα, did not reduce macrophage EBC ability. These data suggest tmTNFα signaling via TNFR2 may have a protective effect which enhances S. aureus clearance. Our work aims to elucidate TLR signaling events through which enhancement of existing host bacterial resolution mechanisms can be achieved. As such, we are investigating whether/how tmTNFα:TNFR2 initiates intracellular signaling pathways that may contribute to upregulation of macrophage mechanisms to enhance pathogen clearance. An in-depth understanding of these signaling events could facilitate development of novel treatment strategies designed to modulate and enhance host immune responses against pathogens, which could be leveraged to circumvent antimicrobial resistance.
Metabolic changes induced by complete Freund’s adjuvant resemble the features of trained immunity
Authors: Mone Kiruthiga , Seravalli Javier , Reddy Jay 
Published: August 2023

Abstract
Using the mouse model of viral myocarditis, we recently reported that animals immunized with complete Freund’s adjuvant (CFA) conferred complete protection against Coxsackievirus B3 infection. Because that Bacillus Calmette-Guérin (BCG) is a well-known inducer of trained immunity and both CFA and BCG possess similar mycobacterial components, we sought to test the hypothesis that the trained immunity might be the underlying mechanism of CFA-mediated protection against CVB3. By using incomplete Freund’s adjuvant (IFA) as a negative control, we investigated the metabolic profiles by mass spectrometry in bone marrow-derived monocytes and CD11b+ cells sorted from splenocytes using LPS as a secondary stimulus. The analysis revealed elevated levels of lactate, α-ketoglutarate, fumarate, malate, and oxaloacetate in the CFA group as compared with the control or IFA groups. In contrast, S-adenosyl methionine and homoserine levels were high in the IFA group. Overall, our data suggest that the metabolites produced in response to CFA were uniquely different from those of IFA. Whether these profiles correlate with the epigenetic changes are currently being investigated.
Supported by grants from NIH (R21, A116673)
TLR4-Independent Mechanisms of Complement Activation During Endotoxemia
Authors: Falguni Mehnaz Mustari , Hunat Junela Cecile , Nunez Kathryn Elizabeth , Ngo Vy , Harberts Erin M 
Published: August 2023

Abstract
Almost two million American adults are diagnosed with sepsis annually of which 350,000 succumb to the infection. Toll-like-receptor 4 (TLR4) canonically recognizes lipopolysaccharide (LPS), an outer membrane structure of Gram-negative bacteria. This recognition leads to pro-inflammatory cytokine release and propagation of other immune compartments. Complement is an acellular innate immune recognition system and has three general categories for activation: classical, lectin and alternative pathway. Previous research has found that complement proteins are dysregulated independent of TLR4 in serum during murine endotoxemia. This study investigates mechanisms of complement activation by describing location of complement gene upregulation and protein distribution in WT and TLR4−/− mice. mRNA was extracted from murine organ samples collected 0, 6, 12, and 18 hours post-induction of endotoxemia. RT-qPCR is then performed to measure expression fold changes of complement genes F5, F13a1, C1qb, Cfd, Masp1, and Mbl1. Genes involved in the lectin pathway were observed to be upregulated at the 6-hour timepoint and then downregulated throughout the progression of disease. C3 is a complement protein that is cleaved to create C3a, an anaphylatoxin, contributing to activation of acute phase inflammatory responses. Levels of C3a are analyzed using Western blots from WT and TLR4−/− mice as a marker of activation. The effects of LPS chemical structure on the efficiency of C3 cleavage is also analyzed. Identification of TLR4-independent pathways will allow for more targeted immune therapies for adverse outcomes related to sepsis.
Supported by National Institute of Health and Towson University Bridges to Doctorate Program NIH (1T32GM146694-01), Fisher College of Science and Math at Towson University, and an FY2022 grant from the Towson University Faculty Development and Research Committee (FDRC) awarded to Erin Harberts titled “Septic Shock: Defining Alternative Pathways of Activation”.
Nitric Oxide (NO) regulation of Dendritic cells (DC) metabolism and immune effector functions
Authors: Gullickson Soyeon , Snyder Julia , del Rio-Guerra Roxana , Sweezy Andrea , Vagher Bay L , Hogan Tyler , Lahue Karolyn , Reisz Julie , D’Alessandro Angelo , Krementsov Dimitry , Amiel Eyal 
Published: August 2023

Abstract
Dendritic cell (DC) activation is characterized by a sustained commitment to glycolysis, a requirement for survival in DC subsets expressing inducible nitric oxide synthase (iNOS, encoded by Nos2 gene). Nitric oxide (NO) can mediate both host-protective and host-cytotoxic effects by interfering with pathogen replication and/or by inhibiting the host mitochondrial respiration, resulting in metabolic rewiring in DCs. These phenomena primarily have been studied in DCs from the classic laboratory inbred mouse strain C57BL/6J (B6), where DCs experience a loss of mitochondrial function due to NO accumulation. To assess the conservation of NO-driven metabolic regulation in DCs, we compared B6 mice to the wild-derived genetically divergent PWD/PhJ (PWD) strain. We show preserved mitochondrial respiration and enhanced post-activation survival in LPS-stimulated PWD DCs due to attenuated NO production. To genetically map PWD’s NO phenotype, we used a congenic mouse strain (B6.PWD-Chr11.2; 11.2) that carries a PWD-derived portion of chromosome 11, including Nos2, on a B6 background. The 11.2 DCs show comparable iNOS expression with lower NO production levels than B6 DCs. We demonstrate that activated 11.2 DCs maintain mitochondrial respiration and TCA cycle carbon flux, compared with B6 DCs. However, reduced NO production by the PWD Nos2 allele results in impaired cellular control of Listeria monocytogenes replication. These studies establish a natural genetic model for restrained endogenous NO production and suggest a useful model to investigate the contribution/regulation of NO in DC metabolism and immune function.
This work was supported by the National Institutes of Health (NIH), National Institute of Allergy and Infectious Diseases (P30GM118228, 1R21AI135385-01A, T32AI055402-15, and R21 AI145306), the NIH, National Institute of Neurological Disorders and Stroke (R01 NS097596), and the National Multiple Sclerosis Society (RG-1901-33309).
Human respiratory syncytial virus activates beta-catenin pathway in lung epithelial cells to regulate pro-inflammatory response
Authors: Mohanty Indira , Pokharel Swechha , Maddison Lisette , Bose Santanu 
Published: August 2023

Abstract
Respiratory Syncytial Virus (RSV) is a non-segmented negative-sense RNA virus belonging to the paramyxovirus family. RSV infects respiratory tract to cause pneumonia and bronchiolitis in infants, elderly, and immunocompromised patients. Effective clinical therapeutic options and vaccine to combat RSV infection are still lacking. Therefore, to develop effective therapeutic interventions, it is imperative to understand virus-host interactions during RSV infection. Canonical Wnt/beta-catenin pathway is a well-established signaling cascade regulating expression of Wnt target genes involved in various biological and physiological functions. Our study shows RSV infection of human lung epithelial A549 cells triggering stabilization of beta-catenin protein and subsequent activation of beta-catenin mediated transcriptional activity. Further studies with beta-catenin inhibitors and beta-catenin lacking cells revealed a role of beta-catenin in positively regulating pro-inflammatory response in RSV infected A549 cells. Activation of beta-catenin during RSV infection was mediated by cell surface receptor complex comprising of frizzled receptors and low-density lipoprotein receptor-related protein 5 and 6 (LRP5 and LRP6). Thus, our studies have revealed an involvement of beta-catenin pathway in inducing pro-inflammatory response during RSV infection. The mechanism(s) and host derived factors regulating RSV-mediated beta-catenin activation will be discussed.
SOCS3 Regulates Dectin-2-Induced Inflammation in PBMCs of Diabetic Patients
Authors: Alrashed Fatema , Haider Mohammed , Albaqsumi Zahraa , Al-Mulla Fahd , Ahmad Rasheed 
Published: August 2023

Abstract
The C-type lectin receptors (CLRs) Dectin-1 and Dectin-2 are involved in several innate immune responses and are expressed mainly in dendritic cells, monocytes, and macrophages. This study aims to evaluate the expression and function of Dectin-2 in peripheral blood mononuclear cells (PBMCs) isolated from diabetic patients and non-diabetic controls. Our results show that Dectin-2 expression was the highest in monocytes compared with other leukocyte subpopulations. The expression of Dectin-2 was also found to be significantly higher in T2D patients monocytes compared with non-diabetic controls. The expression of Dectin-2 was found to be positively correlated with markers of glucose homeostasis, including HOMA-IR and HbA1c. Interestingly, SOCS3, a negative regulator of inflammation, was expressed significantly lower in the PBMCs of T2D patients. Moreover, SOCS3 expression was negatively correlated with Dectin-2 expression level. Further analysis of inflammatory signaling pathways showed a persistent activation of the Dectin-2-Syk-NFkB pathway that was instigated by the diminished expression of SOCS3. Dectin-2 activation failed to induce SOCS3 expression and suppress subsequent inflammatory responses in the PBMCs of diabetic patients. siRNA-mediated knockdown of SOCS3 in PBMCs displayed a similar inflammatory phenotype to diabetic PBMCs when exposed to Dectin-2 ligands. Altogether, our findings suggest that elevated Dectin-2 and its relationship with SOCS3 could be involved in the abnormal immune response observed in T2D patients.
This work was supported and funded by the Kuwait University Research Grant No. [SL01/21] and by the Kuwait Foundation for the Advancement of Sciences (KFAS) grant No. (RA MoH-2022-002).
Impact of Ezh2 on macrophage responses against lipopolysaccharide (LPS), experiments on conditional Ezh2 deletion mice using LysM-Cre system
Authors: Hirankarn Nattiya , Kunanopparat Areerat , Leelahavanichkul Asada , Visitchanakuna Peerapat , Kueanjindaa Patipak , Phuengmaung Pornpimol , Sae-khow Kritsanawan , Boonmee Atsadang , Benjaskulluecha Salisa , Palaga Tanapat 
Published: August 2023

Abstract
Because the macrophage responses to lipopolysaccharide (LPS) might determine the direction of clinical manifestations of sepsis (severe infection), impacts of the enhancer of zeste homologue 2 (Ezh2; a histone lysine methyltransferase of epigenetic regulation) were explored. The transcriptomic analysis on LPS-activated wild-type macrophages demonstrated an alteration of several epigenetic enzymes. Although the Ezh2 silencing, using small interfering RNA (siRNA), in a macrophage cell line (RAW264.7) indicated the non-different LPS responses between Ezh2-reducing cells and the control, higher supernatant TNF-α in Ezh2-reducing cells were demonstrated after twice LPS stimulations (LPS tolerance). With a single LPS stimulation, Ezh2 null (Ezh2flox/flox; LysM-Crecre/−) macrophages demonstrated lower supernatant TNF-α than Ezh2 control (Ezh2fl/fl; LysM-Cre−/−), perhaps due to an upregulation of Socs3 (suppressor of cytokine signaling 3; another inhibitor controlled by Ezh2 gene). In LPS tolerance, Ezh2 null macrophages indicated higher supernatant TNF-α and IL-6 than the control supporting loss of the Ezh2 inhibitory gene. In parallel, Ezh2 null mice demonstrated lower serum TNF-α and IL-6 than Ezh2 control mice after an LPS injection (less severe LPS-induced hyper-inflammation) with similar serum cytokines after LPS tolerance (no reduction of serum cytokines after the 2nd dose of LPS indicating the less severe LPS tolerance). In conclusion, an absence of Ezh2 in macrophages resulted in less severe LPS-induced inflammation with the less severe LPS tolerance (higher cytokine production), partly, through an upregulated Socs3.
Supported by grants from NSRF via the Program Management Unit for Human Resources and Institutional Development, Research and Innovation (B16F640175 and B05F640144). A. K. was supported by the Second Century Fund (C2F) for Postdoctoral Fellowship, Chulalongkorn University.
Characterization of gene alterations during Macrophage Activation Syndrome associated with central nervous system disorders
Authors: Kulangara Varsha Kontham , Nagarkatti Prakash , Nagarkatti Mitzi 
Published: August 2023

Abstract
Macrophage activation syndrome (MAS) is the immense proinflammatory condition that occurs most frequently in patients with systemic juvenile idiopathic arthritis (SJIA) and systemic lupus erythematosus (SLE). An important feature of MAS is central nervous system dysfunction as evident in the form of seizures as well as altered mental status. In current study, MAS was induced in C57Bl/6 female mice by repeated injections of CpG. We performed transcriptome analysis of spleen from MAS and vehicle-treated control mice. Differential expression analysis revealed significantly altered expression of 3873 genes in mice harboring MAS. Pathway analysis indicated upregulation of heme biosynthesis while downregulation of pathways involved in 14-3-3 mediated signaling, oxytocin signaling and dopamine receptor signaling. Decreased expression of genes involved in these pathways was associated with incidents of depression, schizophrenia and Parkinsonism. The major downregulated genes were dopamine receptor D5 (DRD5), glutamate decarboxylase 1 (GAD1) and protein kinase C (PRKC) family of genes. Decreased activity of these genes are reported in depression, schizophrenia, epilepsy and Parkinson’s. At the same time, significant increase in the expression of glutamate ionotropic receptor NMDA type subunit associated protein 1 (GRINA), synuclein alpha (SNCA), glucocerebrosidase (GBA) and tubulin (TUB) genes were observed in MAS induced mice. In this study, we unravel the novel pathways as well as differential expression of genes associated with central nervous system dysfunction during episodes of MAS.
(Supported by NIH grants P01AT003961, P20GM103641, R01ES030144, R01AI129788, R01AI123947 and R01AI160896 to PN and MN).
Ruminococcus gnavus is a pathobiont expanded by genetic susceptibility and dietary tryptophan in a lupus-prone mouse model
Authors: Ma Longhuan , Brown Josephine , Choi Seung-Chul , Elshikha Ahmed , Kanda Nathalie , Terrell Morgan , Ge Yong , Mohamadzadeh Mansour , Morel Laurence 
Published: August 2023

Abstract
Gut microbial dysbiosis has been associated with the development of systemic lupus erythematosus (SLE). Dietary tryptophan modifies the composition of gut microbiota as well as disease activity in a lupus-prone mouse (TC). To directly test the modulatory function of tryptophan on the gut microbiota, we transplanted the gut microbiota from TC and B6 control mice into germ-free or antibiotic treated B6 recipients fed with high or low dietary tryptophan. Interestingly, a putative human lupus pathobiont Ruminococcus gnavus (Rg) was only enriched in the recipients of TC microbiota fed with high dietary tryptophan, which produced anti-dsDNA IgA and presented T cell infiltration in the kidney. A higher level of Rg was detected in untouched TC mice as compared to B6 controls, in correlation with the levels of lupus signature cytokines. Depletion of this bacterium from the gut of TC mice decreased autoantibody production and increased the frequency of regulatory T cells. Conversely, monocolonization of antibiotic-treated TC mice with Rg induced the production of autoantibody as well as increased the frequency of IFN-γ+ T cells, IL-10+ non-T regulatory cells and GC B cells as compared to age-matched TC mice. These results indicate that monocolonization with Rg is sufficient to induce the autoimmune activation in lupus mouse model and that this bacterium is expanded by the combination of lupus genetic susceptibility and tryptophan.
This project is supported by grant RO1 AI143313 from the NIH to LMo.
Discovery and characterization of novel inhibitors of CTP synthase 1 (CTPS1) for the treatment of autoimmune and inflammatory disease
Authors: McElwee Joshua J , Kaila Neelu , Carreiro Samantha , Kumar Sheetal , Toms Angela V , Phadke Avinash , Jacques Suzanne , Caravella Justin A , Kreutter Kevin , Campos Sebastien , Verras Andreas , Albanese Steven K , Demarco Kevin R , DiMattia Michael A , Lynch Eric , Kollman Justin , Tummino Peter 
Published: August 2023

Abstract
The de novo pyrimidine biosynthetic pathway is an inducible cellular program which allows the rapid synthesis of pyrimidine nucleotides in proliferating cells, and the final rate-limiting step is catalyzed by cytidine triphosphate synthase (CTPS1 or CTPS2). A CTPS1 loss-of-function mutation in humans has illustrated the essential and non-redundant role of CTPS1 in activated lymphocyte proliferation. Therefore, selective CTPS1 inhibition is an attractive approach to specifically target pathological immune activity in autoimmune and inflammatory disease.
Using cryo-EM and structure-based drug design, we have identified a series of potent, orally bioavailable, CTPS1-specific inhibitors, exemplified by the compound NTX-871. In-vitro, NTX-871 significantly inhibits the proliferation of T-cell derived lines and activated primary T-cells. These inhibitory effects are reversed by the addition of exogenous cytidine, illustrating the specificity of NTX-871 for CTPS1 and the de novo pyrimidine synthesis program.
NTX-871 was also tested in several mouse in-vivo PD and autoimmune disease models. Oral dosing of NTX-871 significantly reduced T-cell proliferation in an ovalbumin-induced T-cell proliferation model, and QD or BID dosing of NTX-871 significantly improved disease phenotypes in models of delayed-type hypersensitivity, collagen-induced arthritis, and experimental autoimmune encephalomyelitis.
Novel NFkB Variant V213E: Phenotypic Description & Molecular Modeling
Authors: Chaudhri Eman N , Weber Caleb A , Coban Mathew A , Savytskyi Oleksandr V , Squire Jacqueline D , Wierenga Klaas J , Caulfield Thomas R 
Published: August 2023

Abstract

BACKGROUND
Mutations of NFkB1 are a known cause of inborn errors of immunity resulting in immunodeficiency due to the role of NFkB1 as a transcriptional regulator of immunomodulating proteins. We present a patient with a diagnosis of common variable immunodeficiency (CVID), cytopenias with massive splenomegaly, and nodular regenerative hyperplasia of the liver. Our proband, a 22-year-old male, presents with a clinical picture of immunodeficiency, and has a maternal cousin with a similar gene mutation but differing phenotype. Next generation panel sequencing (NGPS) was utilized to discover a novel, single point mutation variant in NFkB1, V213E, that is present in our proband.

METHODS
The novel single-point mutation V213E in the NFkB gene was modeled in-silico using the I-TASSER homology modeling software. Molecular dynamics simulations of both the wild type and variant mutant form fitted to accommodate the novel mutation were conducted and analyzed to assess for possible pathogenicity of the novel mutation.

RESULTS
This variant replaces Valine with Glutamic Acid at position 213 in the transcription regulator’s sequence. We perform molecular modeling to analyze the proteomic impact and difference in molecular dynamics (MDS) which depicted suppressed dynamics in the ankyrin region and death domain of the protein complex. Analysis of the proband’s family showed no significant family history except for the maternal cousin with a mutation in NFkB1.

CONCLUSION
This case both highlights the heterogeneity in phenotype of NFkB1 pathogenic variants as shown in this patient, full penetrance of the variant mutation, and suggests the pathogenicity of a new variant through protein modeling techniques and molecular dynamic simulations.
Tumor Progression Locus 2 Promotes Mouse Plasmacytoid Dendritic Cell Cytokine Secretion and Signaling
Authors: Watford Wendy Tharpe , Shirke Neeti , Choudhury Farhatul 
Published: August 2023

Abstract
The autoimmune disorder systemic lupus erythematosus is thought to be caused by the inefficient clearance of dying cells. This releases nucleic acid debris that stimulates type I interferon (T1 IFN) secretion. Plasmacytoid dendritic cells (pDCs) are the major source of T1 IFNs, which are causally linked to lupus pathogenesis. Both T1 IFNs and pDCs are thus the focus of intense studies for immunotherapies. The serine-threonine kinase, tumor progression locus 2 (TPL2), negatively regulates T1 IFN secretion by conventional dendritic cells (cDCs) and macrophages in response to Toll-like receptor 9 (TLR9) stimulation in vitro. In contrast, we and others have shown that TPL2 is required for T1 IFN production in TLR9-stimulated pDCs. The goal of this study is to validate TPL2-dependent regulation of pDC function in vivo and to delineate the mechanisms responsible. Both cDCs and pDCs develop normally in Tpl2−/− mice, but Tpl2−/− mice show defective secretion of T1 IFNs and proinflammatory cytokines in response to administration of CpG (TLR9) or R848 (TLR7) in vivo. The same defect in T1 IFN and proinflammatory cytokine production was observed in bone marrow-derived pDCs and cDCs in vitro. A modest defect in TLR-induced expression of maturation markers CD80, CD86 and MHC class II was seen in Tpl2−/− pDCs, suggesting impaired NFkB activation. Flow cytometric measurement of phosphoproteins demonstrated that TPL2 is also required for TLR-induced activation of MAPK and ribosomal S6 kinase pathways in pDCs. Ongoing studies are examining the role of TPL2 in TLR trafficking and lupus pathogenesis. These data establish TPL2-dependent regulation of pDC functions, which may be exploited for therapeutic intervention in lupus or other IFN-related diseases.
Supported by grants from NIH/NIAMS (R21 AR075317) titled “Tpl2 regulation of pDC function and SLE pathogenesis”