bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intracellular antibody activates innate immunity (P4135)
Authors: Tam Jerry , McEwan William , Watkinson Ruth , Bidgood Susanna , Mallery Donna , James Leo 
Published: January 2023

Abstract
Immune responses are initiated by infection, yet pathogens evolve faster than the host receptors tasked with their detection. Antibodies can match pathogen evolution but are extracellular whereas viruses replicate intracellularly. Recently however, we showed that viruses carry surface bound antibodies into cells when they infect. Cytosolic antibody-coated viruses are detected by the Fc-receptor and E3 ubiquitin ligase TRIM21, which targets them for proteasomal degradation in a process known as Antibody Dependent Intracellular Neutralization. Here we show that the presence of antibody in the cytosol acts as a highly potent DAMP, alerting the cell to infection and initiating an antiviral state. Upon recognition of an antibody-coated pathogen (eg a DNA or RNA non-enveloped virus or bacteria), TRIM21 synthesizes lysine-63 polyubiquitin chains and activates the NFκB, AP-1 and IRF pathways. Activation by TRIM21 is sufficient to drive production of proinflammatory cytokines, such as IL-6, TNF, CXCL10; as well as modulate surface expression of MHC Class 1-like stress ligands, such as RAE-1, H60 and HLA-E (Qa-1). In nonprofessional cells, such as primary human lung fibroblasts, TRIM21 and antibody are required for detection of adenovirus infection. In primary murine macrophages, TRIM21 mediated signalling promotes a type I immune response. The combination of intracellular antibody and ubiquitous cytosolic Fc-receptor provides a highly potent and rapidly adaptable pathogen sensor.
Involvement of natural immunoglobulin M secreted by epithelial cells in innate immune response (P4155)
Authors: Shao Wenwei , Hu Fanlei , Xiao Lin , Ma Junfan , Huang Jing , Qiu Xiaoyan 
Published: January 2023

Abstract
It is well known that B-1 B cells are the main cell type which is responsible for the production of natural immunoglobulin M (IgM) and can respond to infection by increasing IgM secretion. However, in this study, we reported that some epithelial cells also can secrete natural IgM that has natural IgM characteristics. 1. Epithelial cell-derived IgM revealed germline-encoded and restricted VDJ/VJ rearrangement patterns. 2. Epithelial cells can spontaneously secrete IgM, however, TLR9 agonists, CpG, can increase the secretion of IgM in epithelial cancer cells. 3. The CD79A and CD79B, two molecules that are physically linked to membranous IgM on the surface of B cells to form the B cell antigen receptor (BCR) complex, were also expressed on the cell surface of epithelial cancer cells and co-located with IgM to form BCR-like complex. 4. The epithelial cancer cell-derived IgM showed oligo-reactivity, which can recognize single-stranded DNA, double-stranded DNA, lipopolysaccharide, and some autoantigens. Our findings further expand the understanding for the significance of epithelial cells in the innate immune response, especially in the anti-bacterial immunity via secretion of IgM. In addition, this finding suggested that B-1 B cells may be not the main cell type that is responsible for the production of natural IgM.
Innate immune responses of exfoliated epithelial cells. (P4165)
Authors: Srinivasan Mythily , Swaminathan Venkatesh , Negrini Thais , Arthur Rodrigo 
Published: January 2023

Abstract
Cell exfoliation is a characteristic feature of epithelia covering the external surface and the internal cavities of the body. While the benefit of cytology in infections and cancer diagnosis is well recognized, the clinical use of epithelial cells obtained from body fluids is relatively unexplored. As the first cells to encounter microbes, the epithelial cells exhibit toll like receptors (TLR) that bind specific conserved microbial patterns and transduce signals to thwart deleterious host responses to commensals and pathogens. We evaluated the potential application of epithelial cells derived from human saliva in investigating host responses to microbes. The salivary epithelial cells (SEC) derived from chronic periodontitis saliva exhibited distinct TLR-2 and TLR-4 expression profile and responded differentially to protein peptide derivative and lipopolysaccharides, ligand for TLR-2 and TLR-4 respectively. Interestingly, the ability of SEC to respond was not restricted to stimulation with oral microbes. Co-culture of SEC with Staphylococcus aureus biofilm, a transient cutaneous pathogen upregulated TLR-2 expression and induced increased secretion of inflammatory cytokines IL-6, IL-8, IL-12 and IFN-γ as compared to SEC exposed to a Staphylococcus epidermidis, a skin commensal. Collectively, it is postulated that the SEC is an efficient model to investigate the epithelial:microbe interphase and may serve as personalized specimen for evaluating individual response to biofilm.
Haptoglobin inhibits the pro-inflammatory activity of HMGB1 (P4177)
Authors: Yang Huan , Ju Zhongliang , Lu Ben , Ochani Mahendar , Li Jianhua , Chavan Sangeeta , Tracey Kevin 
Published: January 2023

Abstract
HMGB1 is a cytokine mediator in the pathogenesis of inflammatory diseases including sepsis (Yang et al, BBA, 2009). Recently we demonstrated that haptoglobin (Hp), a naturally occurring serum protein, binds to HMGB1 and suppresses HMGB1-stimulated TNF and IL-8 release in cultured macrophages. Hp knockout mice subjected to cecal ligation and puncture (CLP)-induced sepsis had significantly higher serum HMGB1 levels and higher mortality rates compared to wild type animals (75% survival in wild type vs. 34% in Hp knockout mice; P&lt;0.05). Wild type mice subjected to CLP and received injections of Hp were twice as likely to survive (63% survival in Hp-treated vs. 33% in vehicle control; P&lt;0.05), suggesting the therapeutic potential of exogenous Hp in sepsis. Hp is composed of alpha and beta subunits in a polymeric form (Yueh, J. Chromat B Life Sci. 2007). Structure-functional analysis revealed that Hp beta subunit alone is sufficient to recapitulate effects of Hp to neutralize HMGB1 in vitro in macrophages. The survival advantage of Hp in CLP-induced sepsis was also fully reproduced by Hp beta. Surface plasmon resonance analysis showed that Hp beta binds HMGB1 with high affinity (Kd = 29 nM). Thus, our data reveal unexpected roles of Hp as an endogenous antagonist of HMGB1, preventing the harmful HMGB1-induced inflammation in sepsis. The essential domain of Hp maps to the beta subunit, making it a target in the design of therapeutics.
β-defensins activate human mast cells via Mas-related Gene-X2: cross-regulation by LPS (P4179)
Authors: Subramanian Hariharan , Gupta Kshitij , Lee Donguk , Bayir Arzu , Ahn Harry , Ali Hydar 
Published: January 2023

Abstract
Human β-defensins (hBDs) stimulate degranulation in rat peritoneal mast cells and cause increased vascular permeability in wild-type but not mast cell-deficient rats. Here, we sought to determine if hBDs activate murine and human mast cells and to delineate the mechanisms of their regulation. hBD2 and hBD3 did not induce degranulation in murine peritoneal or bone marrow-derived mast cells in vitro and had no effect on vascular permeability in vivo. By contrast, they induced sustained Ca2+ mobilization and substantial degranulation in human mast cells with hBD3 being more potent. While human mast cells endogenously express G protein coupled receptor (GPCR); Mas-related gene X2 (MrgX2), murine mast cells and rat basophilic leukemia, RBL-2H3 cells do not. Silencing the expression of MrgX2 in human mast cells inhibited hBD2/3-induced degranulation and ectopic expression of MrgX2 in RBL-2H3 cells restored these responses. Interestingly, lipopolysaccharide (LPS) inhibited hBD3 but not hBD2-induced Ca2+ mobilization and degranulation. Thus, hBDs activate human mast cells via MrgX2 and that the resistance of murine mast cells likely reflects the absence of this GPCR. Furthermore, the ability of LPS to inhibit hBD3/MrgX2-mediated mast cell activation provides a novel complexity of the role of mast cells in host defense and inflammation.
Maturational differences between neonatal and adult neutrophils (P4183)
Authors: Lawrence Shelley , Eckert Jeffrey , Pereira Anne 
Published: January 2023

Abstract
Our laboratory has shown that gene expression of multiple microbicidal RNAs is greatly up regulated in neonatal versus adult neutrophils, and that neonates have a higher percentage of circulating immature neutrophils than adults. The aims of this study were to determine if there was a difference in number of immature neutrophils or in the production of microbicidal proteins based on exposure to labor. Design: The ratio of immature to total neutrophils was determined via flow cytometry and complete blood counts. The maturational stage of the neutrophil was verified by neutrophil granule RNA production via Luminex QuantiGene Plex Assays and protein levels via ELISA. Results: Exposure to labor did not affect the number of circulating immature neutrophils in neonates (p=0.864), but those delivered without labor had more neutrophils at the earliest stages of development. There was no difference in α-defensin protein levels between samples, but lactoferrin was elevated in adult as compared to neonates without labor (p=0.0003), but not to those exposed to labor (p=0.087). Conclusion: Labor does not affect the number of immature neutrophils in neonates, but may “push” them to mature. While the gene expression of microbicidal proteins is greatly up regulated in neonatal neutrophils, the amount of protein produced is similar to or lower than adults. Studies are ongoing to determine if protein levels can be increased after stimulation by bacteria or other activators.
Phytoalexin protects dopaminergic neurons against neurotoxicity by modulating myeloperoxidase levels in glial cells (P4199)
Authors: Chang Chi Young , Yoon Hee Jung , Park Eun Jung 
Published: January 2023

Abstract
Myeloperoxidase functions as a key molecular component of the host defense system against diverse pathogens. We have previously reported that increased myeloperoxidase levels and activity is a distinguishing feature of rotenone-exposed glial cells, and that either overactivation or deficiency of myeloperoxidase leads to pathological conditions in the brain. Here, we provide that modulation of myeloperoxidase levels in glia by resveratrol confers protective effects on rotenone-induced neurotoxicity. We show that resveratrol significantly reduced myeloperoxidase levels but did not trigger abnormal nitric oxide production in microglia and astrocytes. Resveratrol-induced down-regulation of myeloperoxidase markedly attenuated rotenone-triggered inflammatory responses including phagocytic activity and reactive oxygen species production in primary microglia and astrocytes. In addition, impaired responses of primary mixed glia from MPO knockout mice to rotenone were relieved by treatment with resveratrol. We further show that rotenone-induced neuronal injury, particularly dopaminergic cell death, was attenuated by resveratrol in neuron-glia co-cultures, but not in neurons cultured alone. Collectively, our findings provide that resveratrol influences glial responses to rotenone by regulating both myeloperoxidase and nitric oxide, and thus protects against rotenone-induced neuronal injury.
Forward genetic analysis of type I interferon responses to cytosolic deoxynucleotides reveals polymorphisms in Tmem173 gene of wild derived MOLF/EiJ mice. (P4201)
Authors: Surpris Guy , Fitzgerald Katherine , Poltorak Alexander 
Published: January 2023

Abstract
We identified a novel phenotype in wild derived inbred mouse strain, MOLF/EiJ (MOLF). In response to cytosolic DNA or cyclic-diadenylate (c-di-AMP), MOLF macrophages exhibit high levels of IL-6 but very low levels of type I interferon, IFNβ, compared to classical inbred mouse strain C5BL/6J (B6). Furthermore, the IFNβ production is reduced in responses of MOLF macrophages to herpes simplex virus (HSV) and Listeria monocytogenes infection that release double stranded DNA and c-di-AMP into the cytosol, respectively. To identify loci that confer the trait, we used quantitative trait locus (QTL) mapping. We measured the IFNβ production of macrophages from a panel of 2nd filial generation (F2), B6/MOLF intercrossed mice, and genotyped the individual mice for inheritance of loci genome wide. The lack of IFNβ production mapped to a locus that contains Tmem173, a gene that encodes STING. STING is an innate immune cytosolic surveyor that mediates interferon response to cytosolic DNA and c-di-AMP. Sequencing the MOLF transcript of Tmem173 revealed multiple single nucleotide polymorphisms and an 18 base pair deletion in the MOLF allele of Tmem173. Almost all of these polymorphisms encode amino acid changes in the putative transmembrane domains of STING, while the cytosolic fraction is highly conserved. In vitro, expression of MOLF STING in Tmem173-/- murine embryonic fibroblasts (MEFs) shows greatly reduced activation of the IFNβ promoter, compared to C57BL/6.
Progranulin regulates endotoxin tolerance (P4143)
Authors: Tang Wei , Liu Lu , Zheng Lin , Lu Yi 
Published: January 2023

Abstract
The growth factor progranulin (PGRN) has been implicated in embryonic development, tissue repair, tumorigenesis, inflammation and host defense. The anti-inflammatory properties of PGRN have been reported in various pathologies and conditions, such as rheumatoid arthritis, but the mechanisms remain to be well resolved. Here we show that pretreatment of recombinant PGRN inhibits the immune response of mouse peritoneal macrophages to LPS, with decreased production of pro-inflammatory cytokines (TNFα, IL-12), and increased production of anti-inflammatory cytokines (IL-10), which displays an endotoxin tolerance-like phenotype. Most interestingly, PGRN deficient peritoneal macrophages show an increased sensitivity toward LPS and a deficient LPS-tolerance induction, and PGRN deficient mice exhibit more elevated lethality and lung injure compared with wild-type mice in response to a subsequent endotoxin. Collectively, these data demonstrate a critical and novel role of PGRN in endotoxin tolerance, and suggest the potential function of PGRN in endotoxin tolerance related diseases, such as sepsis or systemic inflammatory response syndrome (SIRS), hepatic ischaemia, acute coronary syndrome, cystic fibrosis and perhaps even cancer.
Cereblon is a novel E3 ubiquitin ligase regulator of CD28 signaling in T cells (P1007)
Authors: Epling-Burnette Pearlie , Han Ying , Rajadhyaksha Anjali , Mailloux Adam , Jessica McDaniel 
Published: January 2023

Abstract
E3 ubiquitin ligases (E3-UbL) regulate clonal anergy and immune self-tolerance. Of the known regulators, c-Cbl and Cbl-b regulate T-cell growth factor production and proliferation induced by IL-2 through the CD28 pathway. Investigations of immunomodulatory (IMiDsTM) drugs lenalidomide (LEN) and thalidomide in myelodysplastic syndrome and multiple myeloma show that these analogs are capable of activating T-cells in the absence of co-stimulation and reverse T-cell anergy. LEN increased IL-2 production (p&lt;0.001), proliferation (p&lt;0.001), and pCREB promoter binding in primary human T-cells after TCR stimulation alone without CD28-receptor ligation. Comparing LEN-induced response in sorted human CD28+CD8+ and CD28-CD8+ T-cells and in CD28 shRNA knock-down T-cells indicates that LEN acts to directly potentiate receptor function dependent on CD28 expression. A landmark study identified cereblon (CRBN), a RING-domain E3-UbL as the primary target of thalidomide. CRBN has also been shown to mediate LEN immunomodulatory activity in vitro. To examine the effect of CRBN on CD28 signaling, germ-line CRBN knock-out mice (crbn-/-) were studied and found to have normal numbers of mature T-cells, normal naïve and memory compartmentalization, and normal proliferative response, but increased contextual activation of IL-2 in the absence of CD28 ligation. These results reveal a novel E3-UbL regulator involved in CD28 signaling with importance in anti-tumor immunity.
Endosomal Toll-like receptors protect MyD88 from Complement Receptor 3-mediated degradation (P3001)
Authors: Reed Joanne , Buyon Jill , Gupta Vineet , Clancy Robert 
Published: January 2023

Abstract
Activation of Toll-like receptors (TLR) is a vital component of the inflammatory response in diseases characterized by nucleic acid-containing immune complexes. The identification of a biologic break to pathologic TLR signaling would be an important advance. Complement Receptor 3 (CR3) suppresses TLR-mediated inflammation in a murine sepsis model. The current study was initiated to evaluate whether a novel CR3 agonist, Leukadherin1 (LA1), downregulates TLR signaling in macrophages stimulated with hY3, a single stranded RNA that associates with the Ro autoantigen. Macrophages stimulated with either hY3, R848 (TLR7/8 agonist), lipopolysaccharide (TLR4 agonist), or interleukin (IL)-1β secreted TNFα. The addition of LA1 30 minutes prior to stimulation completely inhibited TNFα in all conditions and was accompanied by degradation of MyD88. When LA1 was administered 30 minutes after LPS and IL-1β, the CR3 agonist maintained its ability to inhibit TNFα. In contrast, the addition of LA1 after hY3 or R848 neither inhibited TNFα secretion nor degraded MyD88. These findings demonstrate that LA1 is a potent downregulator of signaling by surface “MyD88-dependent” receptors (TLR4, IL-1R). However, the anti-inflammatory properties of LA1 are negated if ligation of endosomal TLR7/8 has already occurred. In conclusion, CR3 agonists may be most effective in diseases mediated by surface TLR and limited to preventative therapy for autoimmune diseases triggered by RNA containing immune complexes.
The Immune Epitope Database (IEDB): A resource for immunological data related to infectious disease, autoimmunity and allergy. (P3024)
Authors: Vaughan Kerrie , Sette Alessandro 
Published: January 2023

Abstract
The Immune Epitope Database (IEDB) is a freely available repository of epitope data from infectious disease agents, allergy, autoimmunity and transplantation. The IEDB captures details of experiments associated with each epitope and thus provides an information rich resource and user-friendly platform for performing broad-based or more detailed queries. Recent analysis performed using the IEDB, including HCV, allergy, myasthenia gravis and diabetes; highlight the breadth of information accessible through the database, as well as tools and unique features provided therein. Each analysis serves to provide an inventory of all related data, thereby revealing interesting trends, experimental bias and/or knowledge gaps. Features like the Immunomebrowser and Disease Finder can be used synergistically to explore comparative immune reactivity across entire genomes or individual antigens for humans and animal models of disease, and tools like homology mapping can enable visualization of 3D discontinuous B cell epitopes. Moreover, these works provide outreach to the individual community of scientists, help elicit feedback to identify areas for improvement and can serve as ‘tutorials’ for those interested in using the database.
Bcl-XL overexpression prevents B cell receptor driven autophagy in IgM+ lymphoma (P3026)
Authors: Carey Gregory , Sesay Alphius , Roy Sanjit 
Published: January 2023

Abstract
We previously showed that B cell receptor (BCR) induced apoptosis in lymphoma required suppression of PI-3K [Carey GB, Scott DW (2001) J. Immunol, 166: 1618-]. PI-3K stimulates mTOR, a suppressor of autophagy and mitophagy. In addition, Bcl-XL blocks BCR-driven apoptosis in lymphoma, although the underlying mechanism is unclear. In contrast, a recent study demonstrated that Bcl2 overexpression blocked BCR-driven apoptosis, but not the induction of autophagy [Watanabe et al BBRC (2008) 19;374(2):274-]. Therefore the present study examined autophagic and mitophagic responses following BCR crosslinking on parental WEHI-231 lymphoma cells or on a derivative expressing high levels of Bcl-XL (WEHI-231/Bcl-XL). The results confirmed dramatic mitochondrial dysfunction followed by apoptosis in WEHI-231 compared to WEHI-231/Bcl-XL. BCR-crosslinking resulted in rapid and massive induction of the autophagic response in parental WEHI-231 compared to WEHI-231/Bcl-XL. Furthermore, treatment with STF-62247, a small molecule inducer of autophagy, resulted in apoptosis in WEHI-231 but not WEHI-231/Bcl-XL cells. These data suggest that Bcl-XL prevents BCR-driven apoptosis in lymphoma via blocking autophagic and mitophagic responses. Hence, these studies demonstrate specific roles of BclXL and bcl2 in BCR-driven death responses. Lastly, combinations of small molecule autophagy inducers and Bcl-XL antagonists may prove to be effective in addressing lymphoma.
Intracellular free Mg2+ is required to maintain NKG2D expression necessary for controlling EBV infection in XMEN disease (P3028)
Authors: Li Feng-Yen , Chaigne-Delalande Benjamin , O'Connor Geraldine , Lukacs Marshall , Zheng Lixin , Shatzer Amber , Matthews Helen , Su Helen , Cohen Jeffrey , Uzel Gulbu , Lenardo Michael 
Published: January 2023

Abstract
Epstein-Barr virus (EBV) is a B cell-tropic gammaherpesvirus present in latent form in approximately 90% of people worldwide. However, a subset of immunocompromised hosts develop malignancy from uncontrolled EBV infection. While the etiology of such immunodeficiency states is sometimes apparent, as in HIV and post-transplant immunosuppression, the underlying immune deficiency is other cases remains unknown. X-linked immunodeficiency with Mg2+ defect, EBV infection, and neoplasia (XMEN) disease is a novel primary immunodeficiency characterized by deleterious mutations in magnesium transporter 1 (MAGT1), chronic EBV infection and increased susceptibility for EBV-associated lymphomas. We had previously demonstrated that MAGT1 mediates a second messenger role for Mg2+ during T cell activation. Here, we show that loss of MAGT1 also decreases the basal level of intracellular free Mg2+ and abolishes the expression of NKG2D on natural killer cells and cytotoxic T lymphocytes, leading to impaired cytotoxicity against EBV-transformed lymphoblastoid cell lines. Interestingly, both these defects can be restored in vitro and in vivo by exogenous Mg2+ supplementation, leading to decreased EBV-infected cells in vivo. This not only revealed the first specific molecular function of basal free Mg2+ in eukaryotic cells but also identified a novel Mg2+-dependent immune arm of defense against EBV lymphomagenesis that has profound diagnostic and therapeutic implications for XMEN disease.
Possible involvement of transmembrane protein 173 in RANKL-induced osteoclastogenesis (P3012)
Authors: Kim Ju , Shin Yun Ji , Choe Chung Hyeon , Park In Sun , Yu Kang-Yeol , Jang Yong-Suk 
Published: January 2023

Abstract
Osteoclasts play a central role in bone development and remodeling via the resorption of bone and are thus important mediators of bone loss, which leads to osteoporosis. In this research, we investigated the effect of Tmem173 on RANKL-induced osteoclastogenesis via the study of osteoclast differentiation associated gene expression, TRAP activity and NO on Tmem173 overexpressed RAW264.7 cells. The mRNA levels of c-Fos, NFATc1, TRAP and TRAP activity were decreased in Tmem173 overexpressed RAW264.7 cells stimulated by RANKL. In addition, we observed down-regulation NO production and the mRNA levels of NO associated factors such as COX-2 and iNOS. Interestingly, we discovered up-regulation of the Tmem173 by osteoprotegerin (OPG) on Tmem173 overexpressed RAW264.7 cells. OPG prevents interaction of RANKL to RANK by competitive binding to RANKL. These results provide new additional information that Tmem173 played a regulatory role in RANKL-mediated osteoclast differentiation.