bluuebunny/crossref_metadata_2025_split huggingface dataset:
Galectin-3 promotes non-canonical inflammasome activation through binding to glycans on LPS intracellularly
Authors: Lo Tzu-Han , Chen Hung-Lin , Chen Huan-Yuan , Liu Fu-Tong 
Published: January 2023

Abstract
In response to infection, pyroptosis is a typical inflammatory form of cell death. Even though the various stimuli have been well elucidated in the regulation of host immune responses through caspase-1, the mechanism of caspase-4/5/11 is not defined. Lipopolysaccharides (LPS) from Gram-negative bacteria have been shown to induce non-canonical inflammasome activation by binding to caspase-4/5/11 through its lipid A moiety intracellularly and causing oligomerization and activation. Galectin-3, belonging to a beta-galactoside-binding protein family, can bind to LPSs from different Gram-negative bacteria, which are composed of beta-galactoside-containing polysaccharide chains. Galectin-3 is known to self-associate upon binding to multivalent glycans through its non-lectin domain. Therefore, we hypothesized that galectin-3 can cross-link LPS and form an ordered array of galectin-3-LPS complex, and consequently, amplify LPS-induced caspase-4/5/11 oligomerization and activation. To test this hypothesis, we transferred LPSs intracellularly by liposome-mediated transfection into galectin-3−/− bone marrow-derived macrophages (BMDMs) and wild-type cells. We noted galectin-3 deficiency resulted in a lower level of LPS-induced pyroptosis. Co-immunoprecipitation confirmed the interaction between galectin-3 and caspase-11 in RAW264.7 cells after LPS intracellular delivery. In a cell-free system, we showed that galectin-3 facilitated the assembly of LPS-induced caspase-4 oligomerization and activation. In conclusion, galectin-3 is a novel host factor in the induction of higher degree of caspase-4/5/11 oligomerization and activation through LPS binding, resulting in more intense pyroptosis.
Glycolytic regulation of neuroinflammatory response: Role of monocarboxylate transporter 4
Authors: Giri Shailendra , Singh Jaspreet , Suhail Hamid , Kumar Ashok , Rattan Ramandeep 
Published: January 2023

Abstract
Our study aimed to investigate the functional importance of the monocarboxylate transporter (MCT) 4 in vitro, in mouse primary mixed glial cells and in vivo, in mouse brain. Stimulation of primary mixed glial cells with LPS/IFNγ (LI)-induced the expression of MCT4. Inflammatory signals increase glycolysis and lactate production, which have been shown to sustain inflammatory response in immune cells. A real-time increase in glycolysis in LI-stimulated mixed glial cells was observed. We also found that IL-1β and NLRP3 expression was significantly increased in stimulated mixed glial cells, which are associated with chronic inflammatory diseases. MCT4 inhibitor, CHCA, significantly downregulated the proinflammatory response, glycolytic gene expression and real-time glycolysis in the primary mixed glial cells. As expected, CHCA blocked the release of lactate into the culture medium. Knockdown of MCT4 by using siRNA significantly attenuated the proinflammatory response suggesting that MCT4 could be a therapeutic target for neuroinflammatory diseases. Further, targeted metabolomics approach revealed that glycolytic intermediated, phosphoenolpyruvate and ribulose-1,5-bisphosphate, were significantly increased in primary mixed glial cells stimulated with LI, which were significantly decreased by CHCA treatment suggesting that intracellular accumulation of lactate attenuates glycolysis. CHCA treatment also diminished production of cytokines in the brain and spleen cells in an endotoxin mouse model. Importantly, we show that pharmacologic targeting of lactate transporters in glial cells might provide a novel and viable approach to resolve chronic inflammation in metabolic and neurodegenerative diseases.
Mature Tissue-resident Memory T Cells Lose the Responsiveness to Bystander Inflammation
Authors: Liao Wei , Zhang Nu 
Published: January 2023

Abstract
Circulating memory T cells respond to both antigen-specific stimuli and antigen–nonspecific inflammation. IL-18, together with IL-12 induces robust bystander responses from circulating memory T cells. Tissue-resident memory T (Trm) cells represent an essential component of local immunity that elicits immediate response upon cognate antigen re-challenge. However, whether Trm responds to bystander inflammation is not entirely clear. Stepwise induction of CD69 and CD103 marks distinct differentiation stages of mucosal Trms. Because the majority of non-mucosal Trm lacks the expression of CD103, the maturation of non-mucosal Trms is largely unknown. Here, we found that both mucosal and non-mucosal Trms downregulated IL-18 receptor during maturation and largely lost the response to bystander inflammation. Local cytokines including TGF-β and type I IFN control Trm maturation. These data indicate that distinct from circulating memory T cells, Trms limit the response to bystander inflammation to prevent unnecessary collateral tissue damage.
Recruitment of NEMO/IKKγ to TCR microclusters during T cell activation
Authors: Koylass Nicholas Robert , DeRiso Elizabeth A. , Szymczak-Workman Andrea L. , Montecalvo Angela , Murphy Joanne M. , Seminario Maria Cristina , Kane Lawrence P. , Bunnell Stephen C. 
Published: January 2023

Abstract
The IκB kinase (IKK) complex mediates the activation of canonical NFκB isoforms following T cell receptor (TCR) ligation. This complex consists of the kinases IKKα and IKKβ and an essential adaptor subunit, the NFκB essential modulator protein (NEMO). Most models suggest that the IKK complex is activated within oligomeric Carma1/Bcl10/Malt1 (CBM) signalosomes. However, we observed that NEMO enters TCR microclusters before CBM complexes are assembled, within ~70 seconds of TCR engagement. NEMO also entered mobile vesicles and in larger membrane-bounded structures (hereafter ‘macroclusters’). The recruitment of NEMO into TCR microclusters is prevented by Src kinase inhibitors and by the catalytic inactivation of ZAP-70, but occurs in the absence of either SLP-76 or Carma1. Further, NEMO fails to co-localize with TCR-induced CBM polymers. Thus, the recruitment of NEMO to the TCR occurs via a CBM-independent mechanism. The deletion the zinc-finger (ZnF) domain of NEMO disables NFκB signaling and eliminates NEMO from microclusters, while preserving NEMO macroclusters. Since the ZnF domain interacts with polyubiquitin chains, we generated point mutations impacting the ubiquitin-binding site in the ZnF domain and two independent sites within the NEMO ubiquitin-binding ‘NUB’ domain. These mutations impair the ability of NEMO to capture K63-linked and/or linear polymers, hinder NFκB signaling, and eliminate NEMO from microclusters without disrupting NEMO macroclusters. These findings suggest that NEMO is rapidly recruited to polyubiquitin chains associated with the TCR, rather than the CBM complex, and that the CBM complex augments IKK-dependent NFκB signaling via a distinct, recruitment-independent mechanism.
TCR-pMHC bond length controls TCR ligand discrimination
Authors: Huang Jun , Sasmal Dibyendu K. 
Published: January 2023

Abstract
T-cell receptors (TCRs) detect specifically and sensitively a small number of agonist peptide-major histocompatibility complexes (pMHCs) from an ocean of structurally similar self-pMHCs to trigger antigen-specific adaptive immune responses. Despite intense efforts, the mechanism underlying TCR ligand discrimination remains a major unanswered question in immunology. Here we show that a TCR discriminates between closely related peptides by forming TCR-pMHC bonds with different lengths, which precisely control the accessibility of CD3ζ immunoreceptor tyrosine-based activation motifs (ITAMs) for phosphorylation. Using in situ fluorescence resonance energy transfer (FRET), we measured the intermolecular length of single TCR-pMHC bonds and the intramolecular distance of individual TCR-CD3ζ complexes at the membrane of live primary T cells. We found that an agonist forms a short TCR-pMHC bond to pull the otherwise sequestered CD3ζ off the inner leaflet of the plasma membrane, leading to full exposure of its ITAMs for strong phosphorylation. By contrast, a structurally similar weaker peptide forms a longer bond with the TCR, resulting in partial dissociation of CD3ζ from the membrane and weak phosphorylation. Furthermore, we found that TCR-pMHC bond length determines 2D TCR binding kinetics and affinity, T-cell calcium signaling and T-cell proliferation, governing the entire process of signal reception, transduction and regulation. Thus, our data reveal the fundamental mechanism by which a TCR deciphers the structural differences between foreign antigens and self-peptides via TCR-pMHC bond length to initiate different TCR signaling for ligand discrimination.
Regulatory role of Ifit2 in mouse hepatitis virus induced neuroinflammation
Authors: Sarma Jayasri Das , Burrows Amy , Kessler Patricia , Hwang Mi-Hyun , Bergmann Cornelia , Sen Ganes C 
Published: January 2023

Abstract
Interferons (IFNs) are known to protect from virus dissemination and pathogenesis by means of IFN stimulated genes (ISG) but the mechanisms underlying the antiviral effects are not clearly understood. IFN induced tetratricopeptide repeats (Ifit) genes are a class of ISGs represented in mice by Ifit1, Ifit2 and Ifit3. Intracranial infection of mice with MHV significantly increases mRNA levels of all 3 Ifit genes in the CNS. Moreover, Ifit2 is beneficial in limiting encephalitis caused by neurotropic viruses like VSV, WNV, EMCV, and MHV. To provide better cellular insights into the protective mechanisms of Ifit2, we studied viral spread and inflammation in young Ifit2−/− mice (4–5 weeks) infected with MHV-A59. Compared to wildtype (wt) viral spread was rapid and uncontrolled in Ifit2−/− mice and mortality was reduced to 70% by day 6–8 p.i. at 2000 PFU. Also, the pattern of virus distribution in spinal cords was significantly different. Where virus was restricted prominently to the gray-white matter border in wt mice, viral antigen expanded to both white and gray matter in Ifit2−/− mice, but they are less inflamed and less encephalitic. Surprisingly, despite vastly elevated virus load, microglia/macrophage activation was limited compared to wt mice as examined by anti-Iba-1 staining. Moreover, leukocyte recruitment was reduced despite similar induction of inflammatory cytokines. By contrast, type I IFN induction was significantly reduced. At lower viral doses (500 PFU), Ifit2−/− mice developed severe clinical symptoms and myelin damage at the chronic infection stage. Given the homeostatic interactions between microglia and neurons, we suggest that Ifit2 deficiency may disrupt microglial activation and protective functions to neurons.
The RNA binding protein HuR is required for antigen-mediated activation and proliferation of CD4+T cells
Authors: Ellis Jason S , Taylor Tiffany , Atasoy Ulus 
Published: January 2023

Abstract
The RNA binding protein HuR directs helper T cell fate decisions by interacting with 3′ AU-rich elements within the untranslated region of multiple target mRNAs, leading to increased stability and transport to the heavy polysomes. We hypothesized that HuR plays a key role in antigen-induced T cell activation and expansion. HuR was conditionally ablated late during T cell development, immediately before thymic egress (distal Lck-Cre ROSA HuRfl/fl mouse). Upon activation in vitro, HuR KO T cells had significant reductions in Th2 cytokine production (IL-4, IL-5, and IL-13) compared to control cells and greatly increased IL-2. There was no difference in IFNgproduction between HuR KO and controls. Reductions in Gata-3, IL-4 and IL-2Ra (CD25) nascent transcription were also observed. An OVA challenge model of airway inflammation was used to ascertain the effects of HuR KO in vivo. While only half of CD4+T cells in HuR KO mice lack HuR, there was a lack of Th2 responses and these mice had complete amelioration of lung inflammation. OVA challenged HuR KO mice also had significantly reduced BAL IL-13. In parallel, mice were immunized with either OVA or KLH, boosted 10 days later, and antigen specific proliferative responses measured in vitro to investigate antigen-specific T cell responses in the absence of HuR. HuR KO T cells had profound proliferation defects compared to controls, and CD3/CD28 stimulation only partially restored proliferation defects. HuR KO T cells had reductions in STAT5/STAT6 signaling, pathways which are key for Th2 differentiation and function. We conclude HuR plays an indispensable role in regulating antigen-specific activation and proliferation in CD4+T cells, as well as controlling IL-2 homeostasis.
JUUL E-vapor Has Less Protective Effect in a Zebrafish Model of Heart Failure Compared to Nicotine Salt, Nicotine Agonists, and First-Generation ENDS
Authors: Mai Xuyen Kim , Chow Sheryl , Cameron Joshua , O’Barr Stephen A 
Published: January 2023

Abstract
Heart failure (HF) is defined by the impairment of ventricular filling that results in loss of oxygen and damage to the myocardium. HF affects about 2% – 3% of people worldwide in the United States. At the same time, e-cigarette use among young adults has been on the rise because of social norms. The correlation between HF and e-cigarette can be explained by the phenomenon called the “smoker’s paradox”, which states improvement in acute myocardial infarction (MI) and smokers via the interaction between three processes. These processes involve activation of the cholinergic anti-inflammatory pathway (CAP) via the vagus nerve and stimulation of the α7 nicotinic acetylcholine receptor (α7 nAChR). When these processes are activated, inflammatory properties of HF are inhibited. Our lab and others have shown that nicotine salt, α7 nAChR agonists, and first-generation ENDS vapor have potential therapeutic benefit for HF through activation of CAP. In this study, zebrafish were pretreated for 20 minutes over four consecutive days with e-vapor from a flavored JUUL pod, nAChR agonists GTS-21 and AR-R17779, or pure nicotine salt. On day four, MI was induced by chemical induction. Survival times were recorded, and heart tissue was collected for analysis. Regulatory gene and cytokine levels in the myocardium were measured by rtPCR. Results show that nicotine salt, nicotine agonists, and e-vapor from first-generation ENDS have more protective effect as measured by longer survival times and lower regulatory gene and cytokine expression levels, compared to JUUL e-vapor pretreated fish.
The role of the von-Hippel Lindau gene in osteocytes on B lymphocyte maturation and activation
Authors: Chicana Betsabel J , Manilay Jennifer O 
Published: January 2023

Abstract
The von-Hippel Lindau protein (VHL) regulates hypoxia-inducible factor (HIF) degradation, which is involved in cellular adaptation to low oxygen environments. Conditional deletion of Vhl in osteoblasts and in hematopoietic progenitors have demonstrated a role for VHL in these cell types, but how changes in bone homeostasis affects immune development are not fully understood. Osteoblasts (OBs) support B cell development and mature into osteocytes (OCYs). To test if OCYs also support B cell development, we generated OCY-specific (Dmp1-Cre) conditional VHL knockout (cKO) mice. We previously found that cKO mice display dysregulated bone growth, high bone density, smaller bone marrow (BM) cavity volume, and overall decrease in BM cellularity compared to controls. In line with this, the frequencies and numbers of B cell precursors (B220+ IgM−), immature B (B220+ IgMint) and recirculating B (B220+ IgMhigh) cells in the bone marrow are significantly decreased. Although the absolute numbers of B cells in the spleens of cKOs were normal, frequency of B220+ CD19+ cells are decreased, while B1a (IgM+ CD5+) cells are increased. To define the mechanisms by which changes in the bone microenvironment affect B cells, we are investigating oxygenation status, vascular architecture and metabolic profiles of bone and B cells. We hypothesize that loss of VHL in OCYs could permanently and adversely affect B cell functional response. To test this, responses in T-independent and T-dependent antigens will be assessed in cKOs. Taken together, our data suggest that OCY-specific VHL deletion might be helpful to increase bone density, but at the expense of B cells.
LSD1 epigenetically represses NF-κB target genes to regulate marginal zone B cell development
Authors: Haines Robert Richard , Scharer Christopher D. , Boss Jeremy 
Published: January 2023

Abstract
Marginal zone B cells (MZB) are a mature B cell subset that rapidly respond to blood-borne pathogens and are transcriptionally poised to differentiate. Although the transcriptional changes that occur throughout MZB development are known, the corresponding epigenetic changes and epigenetic modifying proteins that facilitate these changes are poorly understood. The H3K4 mono- and di-methyl demethylase LSD1, an epigenetic and transcriptional modifier that promotes plasmablast formation, represents a prime candidate for regulating MZB development because of the high degree of overlap between MZB and plasmablast transcriptomes. B cell-conditional deletion of LSD1 resulted in a two-fold decrease in MZB while follicular B cells (FoB) and bone marrow B cell populations were minimally affected. LSD1 repressed genes in MZB that were normally upregulated in FoB and are involved in adhesion, migration, interferon response, transcriptional regulation, and signaling. MZB lacking LSD1 exhibited alterations in chromatin accessibility at transcription factor family motifs, including NF-κB. The importance of NF-κB signaling was examined through an ex vivo MZB development assay, which showed that both LSD1-deficient and NF-κB-inhibited transitional B cells failed to undergo full MZB development. Gene expression and chromatin accessibility analyses of in vivo- and ex vivo-generated LSD1-deficient MZB indicated that LSD1 regulated the downstream target genes of non-canonical NF-κB signaling. Overall, these data reveal that the epigenetic modulation of the NF-κB pathway by LSD1 is an essential process during MZB development.
Understanding mechanisms of disease tolerance during intestinal helminth infection
Authors: Gentile Marilena , Li Yue , Robertson Amicha , Fontes Ghislaine , Kaufmann Eva , Khan Nargis , Munter Hans M. , Divangahi Maziar , King Irah L. 
Published: January 2023

Abstract
Intestinal helminths infect over two billion people worldwide and can cause significant morbidity. In many cases, however, individuals fail to develop resistance to these tissue-invasive pathogens, indicating that mammalian hosts have evolved unknown strategies to tolerate infection. To investigate the mechanisms underlying host tolerance to helminth infection, we examined the initial tissue invasive stage of Heligmosomoides polygyrus bakeri (Hpb), a natural parasitic roundworm infection of mice. Unexpectedly, we observed a rapid and robust Type 1 inflammatory response that preceded the expected Type 2 immune response. This early Type 1 response was associated with a gut-specific expansion of IFNγ-producing Eomesodermin+ Natural Killer (NK) cells with no increase in other innate lymphoid cell populations. Parabiosis and confocal microscopy studies indicated that Eomes+ NK cells are recruited from circulation and surround the larvae in association with the intestinal vasculature. The recruitment of NK cells to the small intestinal lamina propria is dependent on IFNγ-induced expression of CXCL9 and CXCL10, and the presence of αβ+ T cells. NK cell depletion did not alter worm burden or fitness, but resulted in increased incidence of intestinal bleeding, suggesting a role for NK cells in promoting intestinal vascular integrity. In summary, our work provides new insight into the cellular dynamics required for protection during intestinal helminth infection and will help inform strategies to maximize host fitness in the context of tissue injury and repair.
Interplay of Wnt β-catenin pathway and mTORC1 in pathogenesis of Ehrlichia-induced sepsis
Authors: Haloul Mohamed Abdalla , El Andaloussi Abdeljabar , Ismail Nahed 
Published: January 2023

Abstract
The Wnt/β-catenin pathway has been evolved in regulating cell proliferation, survival, and inflammation in cancer development. However, the role of β-catenin during infections remains elusive. Ehrlichia is obligate intracellular bacteria that cause life-threatening sepsis, characterized by liver injury and dysregulated inflammatory response with no effective therapy available. We examined here the contribution of Wnt pathway to the pathogenesis of Ehrlichia-induced sepsis employing murine models of mild and fatal ehrlichiosis caused by intraperitoneal infection with avirulent Ehrlichia muris (EM) and virulent Ixodes Ovatus Ehrlichia (IOE), respectively. We show that EM infection induces higher activation of the hepatic Wnt/β-catenin pathway and activates Wnt target genes; C-Myc and Cyclin D1 on day 7 post infection compared to uninfected controls. Notably, IOE infection attenuated Wnt/β-catenin pathway in liver tissue, which is associated with inflammasome activation, inhibition of autophagy in macrophages, host cell death, and increased number of replicating bacteria, suggesting that Wnt pathway is a host-protective mechanism that also enhances cell survival and attenuate inflammation during Ehrlichia infection. Notably, pharmacologic or genetic inhibition of mTORC1 activation in IOE-infected mice by rapamycin or MyD88 deficiency, respectively, enhanced Wnt signaling, induced autophagy, and decreased inflammation, suggesting that suppression of Wnt pathway during IOE infection is mediated by mTORC1. These novel findings unravel that virulent Ehrlichia may cause liver injury via mTORC1-mediated inhibition of Wnt pathway. Targeting of mTORC1 could provide a novel therapy for Ehrlichia-induced sepsis.
Renewal rates of CD4 and CD11b cells in mycobacterial granulomas
Authors: Herbath Melinda , Marcus Sarah , Fabry Zsuzsanna , Sandor Matyas 
Published: January 2023

Abstract
Granulomas are the central feature of mycobacterial infections. The majority of granuloma cells are monocytes/macrophages but T cells also play an important role in regulating these lesions. The effector cells in the granuloma have a relatively short life time. Therefore, they must be continuously replaced from the blood. However, the rate of monocyte and T cell recruitment into Mtb-induced lung granulomas is not known and the focus of our work is to measure this rate using intravascular staining.
C57Bl/6 mice were infected via the aerosol route with 200 CFU Mtb H37Rv, expressing tdTomato. Four weeks post infection, the mice were IV injected with anti-CD45 antibody conjugated with BV421, A488 and A647, 24 hours, 4 hours and 3 minutes prior to harvest, respectively. Lung sections were labelled for CD4 and CD11b to test granuloma homing of the stained cells from the blood. A significant fraction of granuloma cells was labelled indicating an access of blood cells to these lesions and a fast turnover of monocytes and CD4 T cells in the granuloma. The cellular turnover differs between different regions, with a higher replacement rate for CD4+ cells (23% in 24 h, from which 16% occurred in the last 4 h) and a slower renewal for CD11b+ cells (19% in 24 h). The rapid cell renewal we observed suggests a therapeutic potential for cell migration blockers in the reduction of Mtb-induced granulomatous pathology. We examine the effect of VEGFR1 and CCR2 blocker treatments on short-term changes in cellular composition and cell distribution in Mtb-induced lung granulomas to demonstrate that this technology offers an approach to study the mechanism of cellular replacement in granulomatous lesions.