bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanical signaling regulates NLRP3 activation in macrophages
Authors: Joshi Hemant , Almgren-Bell Alison , Addanki Anvitha , Todd Elizabeth M , Morley Sharon Celeste 
Published: August 2023

Abstract
Macrophage controls infection and inflammation via releasing pro-inflammatory cytokine IL-1β. NLRP3 inflammasomes assembly triggers a signaling cascade to process pro-IL-1β in the active form via activating caspase-1. In the lungs, dysregulated NLRP3 activation escalates inflammatory diseases such as acute lung injury (ALI), ventilator-induced lung injury (VILI), and idiopathic pulmonary fibrosis (IPF). These inflammatory disorders are associated with changing tissue compliance/stiffness due to accumulated extracellular matrix (ECM). Tissue-resident macrophages interaction with ECM via integrins transduce “mechanotransduction” signaling. However, the molecular mechanism of how mechanotransduction cross-talks with NLRP3 pathways and inflammatory response is not clear yet.
We are examining NLRP3 activation in lung resident alveolar macrophages (AMs) during mechanical stress. For that, we culture macrophages on collagen-coated surfaces with altered stiffness (elastic modulus of 0.2 to 64 Kilo Pascals (kPa)). We observed that the NLRP3 inflammasome pathway is responsive to surface stiffness and IL-1β processing suppressed by a stiffer surface (64 kPa) when compared to a softer surface (0.2 kPa). Similarly, culture surface stiffness also regulates monocyte-to-macrophage differentiation. AMs show altered transcriptome signatures with changing the stiffness and favored activated macrophage phenotype at 0.2 kPa. Further, activation of the integrin-induced signaling also reduced the NLRP3-induced IL-1β release. Future examination of adhesion-based integrin-induced mechanical signaling and NLRP3 pathway will reveal the therapeutic potential in associated inflammatory diseases such as ALI/fibrosis.
National Institutes of Health grants
R01- AI104732, R21EB030171, R01 AI118719, HL148033,
R01AI139540, and R56 AI104732, National Science Foundation
grants CBET-1900277 and CMMI1548571, American Lung
Association grant ETRA 736343, Washington University in Saint
Louis Children’s Discovery Institute grants CDI-CORE-2019-813
and CDI-CORE-2015-505, Foundation for Barnes-JewishHospital
grants 3770 and 4642, American Association of Immunologists
AAICareers in immunology fellowship.
Neutrophil extracellular traps and extracellular histones mediate IL-17 inflammation and bone destruction in periodontitis
Authors: Kim Tae Sung , Silva Lakmali M , Williams Drake Winslow , Wild Teresa Greenwell , Ikeuchi Tomoko , Brenchley Laurie , Kaplan Mariana J , Carmona-Rivera Carmelo , Moutsopoulos Niki M 
Published: August 2023

Abstract
Neutrophil infiltration is a hallmark of the inflammatory disease periodontitis, a prevalent oral condition in which Th17 driven mucosal inflammation leads to destruction of tooth-supporting bone. Herein, we document that in periodontitis, neutrophil extracellular traps (NETs) are early triggers of pathogenic inflammation in periodontitis. In an established animal model of periodontitis, we demonstrate that neutrophils infiltrate disease lesions at early time points after disease induction and expel NETs to trigger mucosal inflammation and bone destruction in vivo. Investigating mechanism by which NETs drive inflammatory bone loss, we find that extracellular histones, a major component of NETs, trigger upregulation of IL17/Th17 responses, and bone destruction. Importantly, human findings corroborate our experimental work. We document, in periodontitis patients, significantly elevated levels of NET complexes and of extracellular histones bearing classic NET-associated post-translational modifications. Strikingly, concentrations of NET components in disease lesions and in circulation, significantly correlate with the severity of bone destruction in patients, even in the absence of known confounding systemic disease. Our findings suggest a feed-forward loop in which NETs trigger Th17 immunity to further amplify neutrophil immunopathology in a prevalent human inflammatory disease.
Bacteroides vulgatus attenuates colitis by inhibiting CD82 and increasing activation of the NLRP3 inflammasome
Authors: Keun Kim Hyo , Yang Chul-Su 
Published: August 2023

Abstract
Inflammatory bowel disease (IBD), involving Crohn’s disease (CD) and ulcerative colitis (UC), is a worldwide disease. IBD is known as a chronic immune-mediated intestinal inflammation caused by a variety of causes, such as genetic, microbial and environmental factors, but the exact etiology and treatment are unclear and undiscovered. Although the correlation between IBD and gut microbiota dysbiosis has not been fully demonstrated, it has long been hypothesized that changes in the microbiome are responsible for IBD. Thus, we analyzed each microbiome using pyrosequencing of the colon of normal mice and DSS-induced colitis mice, and found that the relative abundance of Bacteroides vulgatus(B. vulgatus) was increased in the colon of DSS-induced colitis mice. Next, we confirmed that B. vulgatus regulates CD82 expression and promotes activation of NLRP3 inflammasome. CD82 binds to NLRP3 and BRCC3, with a higher affinity for BRCC3. This binding mediated degradation of NLRP3 by inhibition BRCC3-dependent K63-specific deubiquitination. Therefore, we verified the difference between DSS-induced colitis in CD82 KO mice and normal mice, and the effect of B. vulgatus on DSS-induced colitis in CD82 KO mice and normal mice. Deficiency of CD82 decreased the severity of colitis in mice with enhancing the level of IL-1β and IL-18. Also, administration of B. vulgatus increased the survival through mediating CD82 expression and activating BRCC-dependent deubiquitination of NLRP3 in mice. Taken together, suppression of CD82 reduced the pathogenesis of colitis with elevating the activation of NLRP3 inflammasome by BRCC-dependent K63 deubiquitination. Additionally, B. vulgatus may be a novel therapeutic candidate for colitis.
This work was supported by the NRF grant funded by the Korea government (MSIP) (2019R1I1A2A01064237).
Role of HMGB1 in the activation of innate immune responses during SARS-CoV-2 infection
Authors: Hosakote Yashoda Madaiah , Rayavara Kempaiah , Liang Yuejin , Levine Corri B , Weaver Scott C , Ameredes Bill T , Garg Nisha J , Chopra Ashok K , McLellan Susan , Tseng Chien-Te K 
Published: August 2023

Abstract
The ongoing COVID-19 pandemic caused by SARS-CoV-2 has resulted in overwhelming number of deaths worldwide, affecting all age groups. Due to the emergence and rapid spread of SARS-CoV-2 variants and waning immunity in humans to current vaccines, it is imperative that new treatment modalities must continue to be developed for combating this deadly disease. The molecular mechanisms by which SARS-CoV-2 increases risk of serious respiratory disease is largely unknown but exuberant lung inflammatory and immune responses are key. Understanding of the cascades of events that initiate and sustain inflammatory processes contributing to more severe disease is crucial for developing effective therapies for COVID-19. In this study, we found that the release of high-mobility group box 1 (HMGB1), a proinflammatory mediator that alerts the immune system, was increased in the medium of human lung epithelial cells (A549-ACE2 and Calu-3/2B4) in vitro infected with SARS-CoV-2, and in the serum of SARS-CoV-2 infected mice and humans. Our studies showed that SARS-CoV-2 induced acute inflammation by downregulating the retinoic acid inducible gene-I (RIG-I)-dependent interferon (IFN)-mediated innate antiviral immune response and nuclear factor erythroid 2-related factor (NRF2)-dependent antioxidant mechanism. Treatment with rHMGB1 significantly activated the innate antiviral and antioxidant pathways and inhibited the viral replication. Our studies demonstrated an important role of HMGB1 in the regulation of viral replication and cellular protection as well as the activation of innate immune signaling cascades to promote inflammation. Modulation of HMGB1’s proinflammatory signaling may attenuate SARS-CoV-2-induced lung inflammation.
This work was supported by COVID-19 and Emerging Respiratory Viruses Research Award from American Lung Association (COVID-920427), COVID-19 Bridging grant from Sealy Institute for Vaccine Sciences (C28455), Young Clinical Scientist Award from the Flight Attendant Medical Research Institute (FAMRI) (grant I.D. number 123385), NIH/NIAID R21 AI35619, Short-Term Provost’s Scholar Award by CTSA Mentored Career Development Award, CTSA KL2 COVID Funds (NIH/NCATS KL2TR001441) to YMH.
XIST expression in male leukocytes
Authors: Meester Irene , Frausto Gustavo Alejandro Paniagua , Solis-Soto Juan Manuel 
Published: August 2023

Abstract
XIST expression occurs in human somatic cells possessing more than one X chromosome to balance gene expression and in male germline cells to ensure X chromosome inactivation. A study designed to investigate the sex-biased expression of X-linked immune genes convincingly and repeatedly found low-level XIST expression in male leukocytes.
RNA was extracted from peripheral blood mononuclear cells (PBMC), granulocytes, and oral mucosa from healthy young adults of both sexes (n = 8) by the TRIzol method. After a DNase treatment, RNA was reverse transcribed with a mix of random hexamers and oligodT primers. Real-time PCR was performed in duplicate on 5 ng RNA-equivalent cDNA in duplicate using Taqman primer-probe sets. Negative controls included non-template controls and non-reverse transcribed samples; ref gene, ACTB. Delta Ct between parametric groups were compared by Welch’s t-test.
Control genes behaved as expected: CDH1, was expressed higher in mucosa than in leukocytes (P &lt; 0.04); the Y-linked gene TSMB4Y was expressed in male cells only. Most X-linked immune genes were expressed higher in leukocytes than in mucosa (exception TLR7) with an equal expression between the sexes (0.3&lt;P&gt;0.93) or a sex-biased expression: FOXP3(male-biased, P= 0.04), SH2D1A (female-biased, P= 0.003). Only XIST expression differed from the expected profile, as it was also found in all male leukocyte samples, both PBMC and granulocytes, but not in mucosa samples. The expression levels in male leukocytes were much lower than in female leukocytes (P &lt; 0.0001). Further investigation on XIST expression in male leukocytes will focus on chromosomal localization of lncRNA XIST within male nuclei and the life cycle stage of XIST- expressing male leukocytes.
Supported by UDEM grant UIN20512
DcR3 suppresses LPS-Induced Aggresome-like induced structures in Macrophages via inhibition of ROS and p38 MAPK
Authors: Lin Wan-Wan , Huang Duen-Yi , Lee Chun-Hung 
Published: August 2023

Abstract
Decoy receptor 3 (DcR3), also known as tumor necrosis factor receptor (TNFR) superfamily member 6b (TNFRSF6B), is a pleiotropic factor which modulates cell functions via decoy and non-decoy actions. DcR3 has been shown its anti-apoptotic and anti-inflammatory effects on cancers and inflammatory diseases. Toll-like receptors (TLRs), which are the members of pattern recognition receptors (PRRs), trigger inflammatory response against invading pathogens. However, it remains unclear whether DcR3 plays a role in TLR4-induced inflammatory response. In this study, we demonstrated that in bone marrow-derived macrophages (BMDMs) DcR3 did not affect lipopolysaccharide (LPS)-induced COX-2, iNOS, NLRP3 and pro-IL-1b protein expression. It has been reported that aggresome-like induced structures (ALIS) are formed in response to LPS in macrophages. ALIS, which containing ubiquitinated protein aggregates, are stress-induced response involved in MHC class I antigen presentation. Our findings illustrated that DcR3 can decrease LPS-induced ALIS formation via inhibiting cellular ROS production and p38 MAPK phosphorylation. In addition to LPS, ZnPP-, bafilomycin A1- and MG132-induced ubiquitinated protein expression were reduced by DcR3. Confirming the notion that ALIS is controlled by autophagy, we found that rapamycin can decrease LPS-induced ALIS formation, while bafilomycin A1 can increase LC3-II accumulation with similar extent in WT and DcR3 macrophages. Nevertheless, DcR3 expression does not change p62 and HO-1 expression induced by LPS. Taken together, despite the fact that DcR3 does not alter LPS-induced inflammatory response, our data suggest a novel role of DcR3 in suppression of ALIS formation.
MOST 111-2320-B-002-028
MOF-mediated PRDX1 acetylation regulates LPS-induced macrophage activation
Authors: Chen Hui-Ru , Rabbani Leily , Mittler Gerhard , Rumpf Tobias , Akhtar Asifa 
Published: August 2023

Abstract
Macrophages respond to environmental cues and play a crucial role in host defense, inflammation, and tissue homeostasis. Macrophage activation undergoes metabolic and transcriptomic reprogramming to adapt and tailor an appropriate response, regulating innate immunity. Reactive oxygen species (ROS) have been shown to play a pivotal role in macrophage activation. Nevertheless, the detailed molecular mechanism of how redox signals direct macrophage activation is not fully elucidated. Here, we uncover a role for the lysine acetyltransferase MOF (also known as KAT8) in regulating inflammatory macrophage activation via modulating the acetylation of peroxiredoxin 1 (PRDX1), an H2O2 scavenger. We demonstrate that PRDX1 is a novel substrate of MOF. PRDX1 acetylation is dynamic and reversely regulated by HDAC6 and SIRT2. PRDX1 acetylation fine-tunes its peroxidase activity, leading to modulation of intracellular ROS level upon LPS stimulation. Moreover, PRDX1 acetylation appears to participate in LPS-induced macrophage activation via regulation of H2O2-mediated signal transduction.
A new pipeline denoted SPICE identifies novel JUN-IKZF1 composite elements
Authors: Das Sonali , Li Peng , Pulugulla Sree H , Oh Jangsuk , Spolski Rosanne , Lin Jian-Xin , Leonard Warren J 
Published: August 2023

Abstract
DNA composite elements allow combinatorial transcription factor binding, which is important for fine tuning gene expression in response to physiological stimuli and in pathological conditions. Moreover, composite elements may contribute to epigenetic regulation. Accordingly, developing screening algorithms to identify novel composite elements and their compositions is crucial. Here we report a pipeline termed Spacing Preference Identification of Composite Elements (SPICE), that systematically predicts novel protein binding partners along with their DNA motifs and spacing preferences in a genome wide fashion. Besides predicting known composite elements like AP1-IRF composite elements (AICE) and STAT5 tetramers, SPICE de novo predicted a range of novel binding partners, including JUN-IKZF1 composite elements. We validated JUN-IKZF1 association by co-immunoprecipitation and showed cooperative binding of these factors to an upstream conserved noncoding region, CNS9, in the human IL10 gene based on electrophoretic mobility shift assays. Furthermore, the activity of an IL10 luciferase reporter depended on both AP1 and IKZF1 binding sites within this composite element in mouse B and T cells, confirming its transcriptional relevance. These data establish SPICE as a valuable pipeline for predicting novel transcription factor complexes that regulate gene transcription and provide insights into the biological cooperation of IKZF1 and AP1.
Division of Intramural Research, NHLBI.
Assessing the Role of the VCAM1-VLA4 Interaction in Macrophage Polarization in Pulmonary Metastatic Osteosarcoma
Authors: Kingsley Daniel T , Choi Sung-Hee , Myers Jay , Huang Alex 
Published: August 2023

Abstract
Macrophages are key members of the innate immune system involved in phagocytosis, antigen presentation and other immunological functions. Macrophages are also important players in response to tumor. Their polarization states determine the role that they play in the tumor microenvironment (TME) and are generally regarded as M1-like and M2-like tumor associated macrophages (TAMs). Subsequently, the TME influences how macrophages function in that environment. Osteosarcoma is an aggressive solid tumor and about 20% of patients present with lung metastasis at the time of diagnosis. Pulmonary metastatic osteosarcoma has a low 5-year survival rate of less than 20%. The ability for osteosarcoma to metastasize to the lungs is due, in part, by the expression of Vascular Cell Adhesion Molecule 1 (VCAM1) on its surface. However, it is not well-known how expression of this protein contributes to tumor metastasis. We speculate that the binding interaction between VCAM1 and its integrin α4β1 (VLA4) has some role in this process. Recently, our lab has obtained preliminary data suggesting one of the methods osteosarcomas use to shape macrophages into a pro-tumor (M2-like) phenotype is through the interaction between VCAM1 on its surface and the VLA4 integrin on macrophages. Our data shows that this interaction upregulates expression of the enzyme Arginase 1, (Arg1) a well-accepted marker of M2-polarized macrophages. We speculate that this phenomenon may be, in part, regulated by the protein, suppressor of cytokine signaling 1 (SOCS1), as it inhibits the phosphorylation of the transcription factor, signal transducer and activator of transcription 1 (STAT1); thus, allowing STAT3 to phosphorylate and upregulate M2-associated genes such as Arg1.
St Baldricks Foundation, Keira Kilbane Foundation, Steven G. AYA Cancer Research Fund, Theresa G. & Stuart F. Kline Family Foundation
Neutrophils in the tumor microenvironment (TME) induce T cell non-responsiveness characterized by a shift from proliferation and activation to lipid transport pathways
Authors: Giridharan Thejaswini , Suzuki Sora , Khan A N M Nazmul H , Stokolosa Anna , Long Mark D , Rosario Spencer R , Emmons Tiffany R , Yaffe Michael B , Zsiros Emese , Segal Brahm H 
Published: August 2023

Abstract
Circulating neutrophils (PMN) acquire a T cell suppressor function in the TME characterized by suppression of proliferation, cytokine, and metabolic responses in stimulated T cells. Using ovarian cancer ascites fluid supernatants (ASC) and malignant effusions from other solid tumors as authentic components of the TME, we have identified multiple PMN effector functions including complement signaling, CD11b/CD18 (CR3), and NADPH oxidase drive the suppressor phenotype. Activated PMN also cause CD11b-dependent trogocytosis of T cell membranes, causing membrane injury without inducing T cell apoptosis. We hypothesized that PMN-generated injury cues to T cells cumulatively result in non-responsiveness. We exposed healthy donor unstimulated or CD3/CD28-stimulated T cells to PMN, ASC, or PMN + ASC for 24h, then performed bulk RNA-seq on purified T cells. T cells exposed to PMN + ASC had severe suppression of pathways driving proliferation, protein synthesis, and metabolic pathways, but increased expression of genes associated with lipid and cholesterol transport to the plasma membrane, including CD36 and ATP binding cassettes. Consistent with these results, PMN +/− ASC induced significant upregulation of neutral lipid content on T cell membranes. Further analysis using a metabolism-specific transcriptional pipeline identified upregulation of fatty acid degradation pathways and transporters (CPT1A and SLC25A20). Though not well-studied in T cells, mobilization of lipids to the plasma membrane serves to repair membrane injury. Our results raise the notion that ASC-primed neutrophils induce non-responsiveness in T cells characterized by a shift from stimulated T cell activation to injury repair that enables T cell viability.
NCI Grant Numbers: R01CA188900, R01CA267690
STAT3 restrains dendritic cell function and tumor immunity
Authors: Zhou Jiajia , Tison Kole , Kryczek Ilona , Wei Shuang , Grove Sara , Zhou Haibin , Bai Longchuan , Wang Shaomeng , Zou Weiping 
Published: August 2023

Abstract
STAT3 is considered an oncogene in multiple human cancers. However, its direct involvement in dendritic cell (DC)-mediated antitumor immunity and immune checkpoint blockade (ICB) remains unknown. Here, we found that STAT3 was constitutively activated in DCs and restrained DC function in the tumor microenvironment (TME). Genetic ablation of STAT3 in DCs resulted in enhanced DC function and T cell immunity, thereby slowing down tumor progression in tumor bearing mouse models. Analogously, targeting STAT3 with a proteasome degradation agent, SD-36, preferentially deleted STAT3 expression in DCs, enhanced DC dependent-T cell immunity, and therapeutically synergized ICB in multiple tumor-bearing mouse models. Clinically, the combination of Stat3 expression and DC gene signature correlated with complete response in patients who received ICB. Thus, the STAT3 signaling pathway restrains DC function and targeting STAT3 has the potential to promote an immunologic TME sensitizing immunotherapy.
Identification of T cell Autoantigens in a mouse model of Lupus Nephritis
Authors: Arshad Sanya , Gao David , Kublo Lyubov , Rowe Alex , Wei Wenzhong , Yang Yi , Shlomchik Mark Jay , Tilstra Jeremy , Joglekar Alok 
Published: August 2023

Abstract
Lupus nephritis (LN) is the most common severe organ manifestation of Systemic lupus erythematosus (SLE). Autoreactive CD4+ T cells play a key role in SLE, but the mechanism of loss of self-tolerance and antigen specificity of CD4+ T cells is unclear. CD4+ αβ T cells use their T cell receptor (TCR) to recognize 12–20 residue-long epitopes presented on class II MHC molecules. Identifying CD4+ T cell epitopes has been challenging due to lack of efficient and easy-to-implement methods for epitope discovery. We developed a robust T cell antigen discovery technology that uses chimeric receptors called SABR-II (Signaling and Antigen-presenting Bifunctional Receptors) to express large peptide antigen libraries in the context of MHC molecules. Using SABR-IIs, we sought to identify the autoantigens recognized by kidney-infiltrating CD4+ T cells in a mouse mode of LN – MRL/lpr mice. We used a high-throughput single cell TCR cloning to clone and express 93 TCRs from CD4+ T cells sorted from kidneys of 26-week-old MRL/lpr mice. For antigen discovery, we constructed SABR-IIs with I-Ek and I-Ak (class II MHC allele of MRL/lpr mice) and confirmed their functionality. We built libraries of ~25,000 epitopes derived from nuclear proteins and validated them using a known antigen-specific TCR. We have identified novel putative autoantigens, which will be validated in vitro. This study will lead to identification of novel self-antigens, providing the groundwork for understanding the biology of LN and for development of preventative and therapeutic approaches in SLE.