bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proteasome defects in candle patients’ cells lead to IFN production in both hemopoietic and non-hemopoietic cells (INM6P.416)
Authors: Liu Yin , Biancotto Angelique , Huang Yan , Gadina Massimo , McCoy John Philip , Goldbach-Mansky Rapheala 
Published: January 2023

Abstract
CANDLE (Chronic Atypical Neutrophilic Dermatosis with Lipodystrophy and Elevated Temperature) syndrome is an autoinflammatory disease caused by autosomal recessive mutations in PSMB8 and other subunits of the proteasome. Many IFN regulated genes in CANDLE patients’ whole blood were strongly upregulated and patient monocytes showed STAT1 hyperactivation after IFN-γ stimulation. We hypothesized that cellular stress in CANDLE patients leads to IFN production and asked whether it is restricted to hematopoietic cells. We studied IFN production in PBMCs and fibroblasts from CANDLE patients or in healthy cells treated with proteasome inhibitor epoxomicin. We found increased production of IFN-α and IFN-γ in NK, T and dendritic cells from the two CANDLE patients tested compared with healthy controls. Increased IFN production was reproduced in PBMCs of healthy individuals treated with epoxomicin. We also observed increased IFN-α message in CANDLE patients’ fibroblasts compared to healthy controls. Similarly, epoxomicin treated healthy fibroblasts increased IFN-α message. Interestingly message for other inflammatory cytokines, including TNF-α, IL-1 and IL-6, were either not change or even suppressed. Microarray study showed that IFN regulated genes were upregulated in sorted T, B, NK cells, monocytes and neutrophils. We conclude that proteasome defect causes IFN production in both hemopoietic and non-hemopoietic cells in CANDLE patients that can lead to increased IFN signaling.
Distinct actions of oligomers and fibrils of islet amyloid polypeptide on Toll-like receptor 2 and NLRP3 inflammasome activation (INM7P.423)
Authors: Westwell-Roper Clara , Ehses Jan , Verchere Bruce 
Published: January 2023

Abstract
Aggregation of islet amyloid polypeptide (IAPP) to form amyloid contributes to beta cell dysfunction in type 2 diabetes. Human but not non-amyloidogenic rodent IAPP activates TLR2 and NLRP3 to induce IL-1β secretion by islet macrophages. It is unclear which form of IAPP aggregate induces IL-1β and whether this pathway is relevant to disease pathogenesis. We therefore evaluated the contributions of soluble and fibrillar IAPP to IL-1β secretion by bone marrow-derived macrophages (BMDMs) and assessed the effects of IL-1 receptor antagonist (IL-1Ra) on glucose homeostasis in transgenic mice with beta cell expression of human IAPP. BMDMs treated with soluble but not fibrillar IAPP provided a TLR2-dependent priming stimulus for ATP-induced IL-1β secretion, suggesting that pre-fibrillar species interact with TLR2. Fibrillar but not soluble IAPP aggregates were required for IL-1β secretion in LPS-primed BMDMs and are therefore likely the principal stimulus for NLRP3. Moreover, IL-1Ra (50 mg/kg/d for 8 weeks) improved glucose tolerance in obese human IAPP transgenic mice (AUC=1360±110 vs. 880±70; p&lt;0.05) with no effect in wild-type littermates. These data provide the first in vivo evidence that IAPP-induced islet dysfunction in type 2 diabetes is mediated by IL-1, and suggest that both soluble and fibrillar IAPP aggregates participate in this process. Islet inflammation and amyloid formation are therefore important therapeutic targets to improve beta cell function in type 2 diabetes.
Silencing airway epithelial cell-derived hepcidin exacerbates acute lung injury by regulating the intracellular iron status in alveolar macrophages (INM7P.434)
Authors: Chen QiXing 
Published: January 2023

Abstract
Objective: Hepcidin is a β-defensin-like antimicrobial peptide and acts as a principal iron regulatory hormone. Hepcidin is mostly produced by hepatocytes, but is also expressed by other cells, such as airway epithelial cells. However, nothing is known about its function in lung infectious and inflammatory disease such as acute lung injury. Methods: Acute lung injury was induced by polymicrobial sepsis via cecal ligation and puncture surgery. Adenovirus-mediated short hairpin RNA specific for the mouse hepcidin gene hepc1 and control adenovirus were intratracheally injected into mice twice. The adenovirus-mediated knockdown of hepcidin in airway epithelial cells was evaluated in vivo. Lung injury and the 7-day survival rate were assessed. The local and systemic iron content was assayed. Results: The hepcidin level in airway epithelial cells was upregulated during polymicrobial sepsis. The knockdown of airway epithelial cell-derived hepcidin aggravated the polymicrobial sepsis-induced lung injury and pulmonary bacterial infection and increased the mortality. Moreover, the knockdown of hepcidin in airway epithelial cells led to reduced ferroportin degradation and a low intracellular iron content in alveolar macrophages, but did not affect the STAT3/SOCS3 axis. Conclusions: Airway epithelial cell-derived hepcidin plays an important role in protection against acute lung injury via regulating the intracellular iron status in alveolar macrophages.
Blockade of mTOR in innate immune system represents an effective strategy to boost Toll-like receptor-induced Th1 response for vaccine (INM7P.428)
Authors: Xiao Hui , Zang Aiping , Ma Dapeng , Yuan Chuangping , Du Min , Huang Zhong , Xiao Jianhua , Lan Ke , Li Xiaoxia 
Published: January 2023

Abstract
Development of better adjuvant is urgently needed for vaccines whose efficacy depends on potent Th1 response. While TLR ligands represent the most promising adjuvants for Th1 response, induction of only suboptimal IL-12 but evident IL-10 in DCs may limit their efficacy. In this study, we attempted to test the notion that maximizing TLR-induced IL-12 versus IL-10 ratio in innate immune system can be a viable approach to elicit robust Th1 response for vaccine. Systemic screening identified a dozen of small molecule compounds capable of elevating LPS-induced IL-12p70 production in DCs. Interestingly, blocking mTOR directly by Rapamycin, or indirectly by compounds targeting mTOR’s upstream regulator PI3K or ERK, respectively, was able to consistently increase IL-12 but decrease IL-10 induction in LPS-stimulated DCs and macrophages. Our study further demonstrated that blocking mTOR in the innate immune system by a variety of compounds can effectively improve MPL-induced Th1 and antibody responses for HBV vaccine. Moreover, we identified a subset of transcriptional factors whose expression in innate immune cells depends on mTOR activation, whereby revealing novel mechanisms by which mTOR regulates TLR-induced IL-12 and IL-10 expression. In summary, our results suggest that maximizing IL-12 vs IL-10 ratio in innate immune system by blocking mTOR can be a novel approach to boost TLR-induced T cell response for vaccine.
Allele-specific induction of interleukin-1beta expression by CEBP-beta and PU.1 contributes to increased tuberculosis susceptibility (INM8P.451)
Authors: Chen Xinchun , Zhang Guoliang , Zhou Boping , Li Shaoyuan , Wen Yuxin , Yang Hui , Zhan Senlin , Zhang Mingxia , Zeng Gucheng , Feng Carl , Sassetti Christopher 
Published: January 2023

Abstract
Mycobacterium tuberculosis infection is associated with a spectrum of clinical outcomes, from long-term latent infection to different manifestations of progressive disease. Pro-inflammatory pathways, such as those controlled by IL-1beta, have the contrasting potential both to prevent disease by restricting bacterial replication and to promote disease by inflicting tissue damage. Thus, the ultimate contribution of individual inflammatory pathways to the outcome of M. tuberculosis infection remains ambiguous. In this study, we identified a naturally-occurring polymorphism in the human IL1B promoter region, which alters the association of the CEBPbeta and PU.1 transcription factors and controls the expression of IL-1β. The high-IL-1β expressing genotype was associated with the development of active tuberculosis, the severity of pulmonary disease and poor treatment outcome in TB patients. Higher IL-1β expression did not suppress the activity of IFN-γ-producing T cells, but instead correlated with neutrophil accumulation in the lung. These observations support a specific role for IL-1β and granulocytic inflammation as a driver of TB disease progression in humans, and suggest novel strategies for the prevention and treatment of tuberculosis.
Actelated dextran microparticle delivery as a means to generate regulatory myeloid cells (IRC5P.470)
Authors: Papenfuss Tracey , VanGundy Zachary , Strange Heather , Bachelder Eric 
Published: January 2023

Abstract
Myeloid cells (MC) have potent regulatory abilities but factors influencing the development of such regulatory myeloid cells (MC-regs) remain poorly understood. Retinoic acid (RA) is a metabolite of vitamin A that has regulatory abilities and impacts myeloid cell differentiation. We have previously shown that RA produces MC-regs that expressed increased IL-10, regulatory T (Treg) cells, and were able to suppress the proliferation and cytotoxicity of CD4+ and CD8+ T cells, respectively. We hypothesize that encapsulation of RA within acetalated dextran (AC-DEX) microparticles (MPs) can be used for targeted generation of MC-regs in vivo. We used MPs containing encapsulated FITC-labeled BSA to determine the relative uptake of Ac-DEX MPs by myeloid cell populations in vitro and in vivo. We found that labeled MPs were readily taken up by macrophages, DCs and myeloid progenitors in vitro. Following in vivo injection, increased percentage of FITC+ cells was seen in both CD11c+CD11b- and CD11c-CD11b+ cells in draining lymph nodes (DLN) over controls of free FITC or empty MP administration. When RA was encapsulated into MPs, CD11b+ cells within the DLNs had a increased PD-L1 expression and proliferation in DLNs was decreased. These results suggest that in vivo targeted delivery of regulatory compounds by Ac-DEX MPs can induce MC-regs which may be useful to treat inlammatory and immune-mediated diseases.
In vivo role of HMGB1 in endotoxemia and bacterial infection (IRC5P.454)
Authors: Matsuda Atsushi , Yanai Hideyuki , Taniguchi Tadatsugu 
Published: January 2023

Abstract
High-mobility group box protein 1 is nuclear protein conserved among almost all eukaryotic cells. HMGB1 is thought to be a danger signal mediator when it is released both actively from activated immune cells and passively from dead cells into extracellular milieu upon pathogen infections or sterile inflammations. Released HMGB1 act as an inflammatory cytokine and promote inflammatory disorders. However, in vivo function of HMGB1 is still elusive since Hmgb1 gene-deficient mice are lethal. In this study, by using Hmgb1 gene conditional knockout mice which we have established recently, we examined the role of HMGB1 in innate immune responses and inflammation in vivo. We successfully generated Hmgb1fl/flLysM-Cre+ mice because it has been reported that HMGB1 is released from myeloid cells. They developed without significant anomaly and HMGB1 is deleted from macrophages. Interestingly, we observed that, in LPS induced endotoxin shock model, Hmgb1fl/flLysM-Cre+ mice became more sensitive while plasma HMGB1 level of Hmgb1fl/flLysM-Cre+ mice is comparable with wild-type control. These mice also became more susceptible to bacterial infection. In this poster session, we would like to discuss these and recent data further.
Suppressive monocytes: homeostatic mechanism to restrain chronic intestinal inflammation. (IRC5P.455)
Authors: Ostanin Dmitry , Kurmaeva Elvira , Bhattacharya Dhruva 
Published: January 2023

Abstract
Chronic intestinal inflammation in patients with inflammatory bowel diseases (IBD) is fueled by complex and poorly understood interactions between T cells and myeloid cells that are constantly recruited from blood into the affected regions of the gut. We undertook this study to characterize the interplay between colitis-induced myeloid cells and CD4 T cells in CD45RBhigh T cell-induced colitis model. Within massively expanded CD11b+Gr-1+ splenocytes in colitic mice, only Ly6Chigh inflammatory monocytes suppressed proliferation and production of cytokines by CD4 T cells. Suppression was mediated by cell-contact, nitric oxide (NO), and partially by IFN-γ and prostaglandins. Ly6Chigh cells isolated from colitic colons showed upregulation of inducible NO synthase (iNOS) and arginase-1 and were more potent suppressors than those from spleen. Morphological and phenotypical analysis revealed that colon Ly6Chigh cells were macrophage-like (CD115-CD64+) but did not express MHC-II, CD11c, or F4/80. They secreted IL-10 and IL-1β/IL-6 and, upon co-culture with naïve T cells, promoted their differentiation into foxp3+ T cells and Th17 cells, respectively. Taken together, recruitment of inflammatory monocytes into inflamed intestine enhances their suppressive properties and may also arrest their further differentiation. Thus, monocyte recruitment to areas of chronic inflammation may represent an important homeostatic mechanism aimed at restraining and/or reshaping T cell responses.
Characterization of human CS1 gene promoter in NK and B cells (IRM7P.485)
Authors: Mathew Stephen , Kim Jongrok , Mathew Porunelloor 
Published: January 2023

Abstract
CS1 (CRACC, SLAMF7 or CD319) is a member of SLAM (Signaling Lymphocyte Activation Molecule) family receptors and is expressed on NK cells, CD8+ T lymphocytes, mature dendritic cells and activated B cells. Unlike other SLAM members, CS1 shows SAP (SLAM-associated protein) independent but EAT-2 (Ewing’s Sarcoma associated transcript) dependent signaling in human NK cells. CS1 has been shown to be overexpressed in multiple myeloma (MM) and a humanized monoclonal antibody against CS1 is in phase 2 clinical trial for MM. In this study, we analyzed the transcriptional regulation of human CS1 gene. In contrast to the multiple transcription initiation sites in human and mouse 2B4 genes that are driven by TATA-less promoters, we found that proximal region of CS1 promoter contains CAAT box and atypical TATA-box that might result in common transcription initiation at -29 nucleotides upstream of the ATG translation start codon. Relative luciferase activities of successive deletion mutants of CS1 promoter were different between Blimp-1-positive YT cells and Blimp-1-negative DB cells. Our electrophoretic mobility shift assay indicates that Blimp-1 binds to putative Blimp-1 binding site at -750 to -746 region of CS1 promoter. This suggests a possible activating role of Blimp-1 transcription factor in certain circumstances. Understanding CS1 gene expression and regulation will help in developing immune based therapy for B cell-mediated diseases, such as SLE and MM.
FCRL5 promotes T cell-independent innate-like B cell responses and counter-regulates tolerance through the Lyn/SHP-1 circuit (IRM8P.717)
Authors: Becker Eugene , Zhu Zilu , Won Woong-Jai , Dalla-Favera Riccardo , Davis Randall 
Published: January 2023

Abstract
The earliest phases of humoral defense are orchestrated by splenic marginal zone (MZ) and body cavity-derived B1 B cells. These frontline responders have been termed “innate-like” given their broadly-reactive natural antibody repertoires and capacity for rapid responses to T cell-independent (TI) antigens. Despite their key contributions to primary responses, why these cells possess such prompt responsivity to innate-stimulation is poorly understood. The discovery of a family of Fc receptor-like (FCRL) molecules with homology to the classical FCRs for IgG and IgE, complex tyrosine-based function, and preferential B cell expression has introduced a new level of humoral regulation. Although their in vivo functions have not yet been investigated, human FCRL (hFCRL) members are becoming increasingly appreciated for their associations with immune-related diseases. In particular, hFCRL3 has emerged as a generalized risk factor in autoimmunity. To better understand the role of hFCRL3 in B cells, we investigated its closest relative mouse FCRL5 (mFCRL5). This molecule shares homologous extracellular domains, binary tyrosine-based signaling, and innate-like B cell expression. Here we demonstrate that Fcrl5 deficiency impairs humoral responses to TI antigens and differentially modulates autoimmunity in lupus-prone SHP-1 and Lyn mutant mice. These data indicate a critical role for mFCRL5 in regulating innate-like B cell function at the interface of host defense and tolerance.
AID-initiated DNA lesions are differentially processed in distinct B cell populations (IRM8P.701)
Authors: Wang Jing , Chen Zhangguo , Ranganath Sheila , Viboolsittiseri Sawanee , Eder Maxwell , Elos Mihret , Chen Xiaomi , Hansen Erica 
Published: January 2023

Abstract
Activation-induced deaminase (AID) initiates U:G mismatches, causing point mutations or DNA double-stranded breaks at immunoglobulin (Ig) loci. How AID-initiated lesions are prevented from inducing genome-wide damage is not completely understood. Prior studies proposed a differential DNA repair mechanism that protects certain non-Ig loci such as c-myc from AID attack. However, determinants that regulate such protective mechanisms remain largely unknown. To test whether target DNA sequences might modulate protective mechanisms via modifying the processing manner of AID-initiated lesions, we established a knock-in model by inserting an Sγ2b region, a bona fide AID target, into the first intron of c-myc. Unexpectedly, we found that the inserted S region did not mutate or enhance genomic instability of c-myc, due to error-free repair of AID-initiated lesions, in antigen-stimulated germinal center B cells. In contrast, cytokine-activated B cells display a much higher level of c-myc genomic instability in an AID- and S region-dependent manner. Our findings reveal a complex interplay between target sequence, DNA repair mechanism, and cellular context associated with differential transcription, which coordinately regulate genome stability. Our studies could provide mechanistic insight into differential routes to AID-mediated genetic alterations in distinct subtypes of common B cell lymphomas.
Novel role of the E26 transformation-specific transcription factor Spi-C for B cell development and function (IRM8P.703)
Authors: Li Stephen , DeKoter Rodney 
Published: January 2023

Abstract
Transcription factors of the E26 transformation-specific family are critically important for regulating B cell development and function. Spi-B and Spi-C are highly related E26 transformation-specific transcription factors that can bind to identical DNA sequences in the genome. Spib-/- mice have reduced follicular and increased marginal zone B cell frequencies compared to WT mice. Spib-/- B cells are defective in BCR signaling, and cannot generate T-dependent antibody responses. Spi-C is expressed in developing B cells, but its function in B cell development and function is not clear. To determine if Spi-B and Spi-C are functionally redundant, we generated mice that are germline knockout for Spib and heterozygous for Spic (Spib-/-Spic+/-). Spib-/-Spic-/- mice were not born, potentially due to embryonic lethality. Interestingly, Spib-/-Spic+/- mice had restored number of B cells in the spleen, including a rescue of follicular B cells, and had restored proliferative responses compared to Spib-/- mice. Transcripts of genes important for BCR signaling were rescued in sorted follicular Spib-/-Spic+/- B cells compared to Spib-/- B cells. These results suggest a novel role for Spi-C in opposing Spi-B in B cell development and function. These findings have important implications for understanding antibody forming responses, such as those seen in vaccinations.
Receptor interacting protein-2 plays a critical role in human lung epithelial cells survival in response to Fas-induced cell-death (IRM9P.731)
Authors: Rahman Mohd. , Sundaram Kruthika , Srabani Das , Gavrilin Mikhail , Wewers Mark 
Published: January 2023

Abstract
Lung epithelial cell death is critical to acute lung injury. It is known that FasL plays a prominent role in lung cell death and may work in part through activation of the receptor interacting protein-2 (RIP2). RIP2 is serine/threonine kinase with a C-terminal caspase activation and recruitment domain (CARD). This CARD contains a highly conserved, predicted tyrosine phosphorylation site. Thus, involvement of tyrosine phosphorylation in the CARD domain of RIP2 may play a critical role in Fas-mediated apoptosis in the human lung. To test this hypothesis, human lung epithelial cells (BEAS-2B) were induced to undergo cell death in response to the Fas agonist antibody CH11 with and without manipulation of endogenous RIP2 concentrations. We show that CH11 increases lung epithelial cell death in a dose-dependent manner as determined by LDH release and nuclear condensation. Fas-induced LDH release was inhibited by RIP2 knock-down. Reduced levels of RIP2 in BEAS-2B cells after treatment with RIP2 siRNA were confirmed by immunoblot. Overexpression of RIP2 in BEAS-2B cells synergized with Fas ligand-induced LDH release in a dose-dependent manner. Finally, mutation of the tyrosine phosphorylation site in CARD of RIP2 protected BEAS-2B cells from Fas ligand induced cell death. Thus RIP2’s CARD tyrosine phosphorylation may represent a new therapeutic target to promote the survival of human lung epithelial cells in disorders that lead to acute lung injury and ARDS.
Structural motifs suggestive of hydrolytic activity are common among three-dimensional antibody structures (IRM9P.722)
Authors: Bowen Anthony , Casadevall Arturo 
Published: January 2023

Abstract
Naturally occurring catalytic antibodies are associated with both positive and negative outcomes in autoimmune disease and infection, but their function and prevalence remain unclear. Two monoclonal antibodies to Cryptococcus neoformans were shown to hydrolyze several peptide antigen mimetics. These two antibodies had distinct peptide hydrolysis patterns, which were altered, but not blocked, by alanine substitution of peptide residues, indicating a non-sequence-specific mechanism. A putative serine-protease-like active site was identified in the light chain variable region of both molecules. A computational algorithm was developed to detect similar sites present in other antibody structures. A three-dimensional reference template corresponding to the putative active site was optimally superposed with all possible templates in the other antibody structures. Hits were defined as those superpositions with an RMSD ≤ 1Å. The putative site was found in 24 of 80 known catalytic antibody structures and was found in 126 of 1367 studied antibodies with no annotation of catalytic activity. The ability of many antibodies to cleave antigen, albeit slowly, would provide a new function to immunoglobulin molecules in host defense. Confirmation of this active site is being pursued through site-directed mutagenesis. We anticipate that these studies will provide insights into the design of anti-cryptococcal therapies and the role of catalysis as a function of humoral immunity.