bluuebunny/crossref_metadata_2025_split huggingface dataset:
β-defensins that bind CCR6: Blunting the permissiveness of Th17 cells to HIV infection (P4432)
Authors: Christensen-Quick Aaron , Lafferty Mark , Goicochea Marco , Garzino-Demo Alfredo 
Published: January 2023

Abstract
HIV preferentially depletes IL-17-producing, CD4+ “T helper 17” (Th17) cells from the gut during the acute phase of infection. Th17 cells play a key role in mucosal barrier maintenance and protection against opportunistic infections commonly associated with HIV/AIDS. In response to IL-17, epithelial cells of mucosal barriers secrete β-defensins - a family of secreted, cationic peptides with potent broad-range antimicrobial activity against bacteria, fungi, and viruses including HIV. Our laboratory has shown that the expression of human β-defensin 2 (hBD2) is markedly decreased in the oral mucosa of HIV+ subjects, and that β-defensins, in addition to direct antimicrobial activity, upregulate the HIV restriction factor APOBEC3G via the chemokine receptor CCR6, which is expressed on Th17 cells. In order to characterize the effects of HIV infection on the Th17 subset and determine if β-defensins can protect Th17 cells from HIV infection, activated human primary CD4+ T cells are infected and/or treated with β-defensin, then characterized by flow cytometry. Our results show that IL-17A+ cells from peripheral blood are highly permissive to HIV, and are preferentially lost during infection. In addition, our model suggests that Th17-polarizing cytokines enhance HIV infection, and that β-defensins can protect these cells from infection. Our studies of the factors contributing to protection of Th17 cells may yield new therapeutic targets to protect the Th17 compartment.
In vitro characterization of GS-9620, a toll-like receptor 7 agonist (P4441)
Authors: Hesselgesser Joe , Frey Christian , Duatschek Paul , Halcomb Randall , Zheng Jim , Tumas Daniel , Wolfgang Grushenka 
Published: January 2023

Abstract
Efficient innate and adaptive immunity is necessary for initial containment and subsequent clearance of viral infections, including hepatitis B and C viruses. A feature of an effective anti-viral immune response is the interaction of single stranded viral RNA with toll-like receptor 7 and activation of plasmacytoid dendritic cells and B lymphocytes. In this study, the novel toll-like receptor 7 agonist GS 9620 was characterized in regards to its toll-like receptor selectivity and its ability to activate innate and adaptive immune responses in vitro. GS 9620 selectively activated human toll-like receptor 7 over other toll-like receptors and induced several cytokines and chemokines in a concentration dependent manner. In particular, GS-9620 was able to induce secretion of interferon-alpha at 55-fold lower concentrations compared to those that induce tumor necrosis factor in human PBMCs and isolated plasmacytoid dendritic cell cultures. We also detected GS-9620-dependent induction of interferon stimulated gene expression in PBMCs. Moreover, GS-9620 transiently induced the expression of the activation markers CD25 and CD69 in both CD3+CD4+ and CD3+CD8+ T lymphocyte subsets as well as up-regulated expression of CD69 and the co-stimulatory molecule CD86 on CD20+ B lymphocytes. In conclusion, GS-9620 is a potent and selective toll-like receptor 7 agonist that activates innate and adaptive antiviral immune responses which is currently being evaluated in human clinical trials.
The phosphatase and tensin homolog PTEN improves murine polymicrobial sepsis outcome by decreasing MyD88 expression. (P1344)
Authors: Sisti Flavia , Ferreira Ana , Wang Suojuan , Filgueiras Luciano , Wang Zhuo , Cunha Fernando , Alves-Filho Jose , Serezani C. Henrique 
Published: January 2023

Abstract
Sepsis is systemic inflammatory response caused by an infectious agent and may progress to multiple organ dysfunction and death. Therapeutic strategies to inhibit excessive inflammation in sepsis are needed. The lipid and protein phosphatase PTEN is a well-known tumor suppressor, but its role in host defense is poorly studied. Here, we investigated whether PTEN activation is involved in TLR activation in vivo and in vitro. PTEN expression is decreased in cells from the peritoneal cavity 24 h after cecum ligation and puncture (CLP). In vivo pretreatment with the PTEN inhibitor bpV(HOpic) 150 ug/Kg for 1 hour before cecum and ligation puncture decreases animals survival, associated with high bacterial number in the peritoneal cavity when compared to untreated mice. In vivo PTEN inhibition increases expression of the TLR adaptor MyD88 during sepsis. In vitro, LPS (TLR4) and PAM3Cys (TLR2) increase PTEN phosphorylation in thyoglicolate-elicited macrophages (MΦs). PTEN mRNA silencing further enhances MyD88 expression and TLR-2 and -4-induced IRAK and NFkB p65 phosphorylation. Transfection of MΦs with adenovirus expressing constitutively active PTEN decreases MyD88 expression. Together, our data show that PTEN is a key determinant of macrophage TLR activation by decreasing MyD88 expression, leading to reduced systemic inflammatory response and therefore improving sepsis outcome.
Cyclic GMP-AMP Synthase (cGAS) is a cytosolic DNA sensor that activates type I interferon pathway by generating a second messenger (P1346)
Authors: Sun Lijun , Wu Jiaxi , Chen Zhijian 
Published: January 2023

Abstract
The presence of DNA in the cytoplasm of mammalian cells is a danger signal that triggers the host immune responses such as the production of type-I interferons (IFN). This DNA signaling pathway requires the adaptor protein STING and the transcription factor IRF3, but the mechanism of DNA sensing is unclear. Here we showed that mammalian cytosolic extracts synthesized cyclic-GMP-AMP (cGAMP) in vitro from ATP and GTP in the presence of DNA but not RNA. DNA transfection or DNA virus infection of mammalian cells also triggered cGAMP production in vivo. cGAMP bound to STING, leading to the activation of IRF3 and induction of interferon-β. Thus, cGAMP represents the first cyclic di-nucleotide in metazoa and it functions as an endogenous second messenger that triggers interferon production in response to cytosolic DNA. Through biochemical fractionation and quantitative mass spectrometry, we identified a cGAMP synthase (cGAS), which belongs to the nucleotidyltransferase family. Overexpression of cGAS activated the transcription factor IRF3 and induced IFNβ in a STING-dependent manner. Knockdown of cGAS inhibited IRF3 activation and IFNβ induction by DNA transfection or DNA virus infection. cGAS bound to DNA in the cytoplasm and catalyzed cGAMP synthesis. These results indicate that cGAS is a cytosolic DNA sensor that induces interferons by producing the second messenger cGAMP.
In dendritic cells Toll-like receptor-dependent induction of IL-12p70 is accompanied by a profound down regulation of sphingosine-1-phosphate lyase mRNA (P1348)
Authors: Radeke Heinfried , Arlt Olga , Ranglack Annika , Pfeilschifter Josef 
Published: January 2023

Abstract
Sphingosine-1-phosphate (S1P) is an immune modulator produced by sphingosine kinase (SphK)1 and SphK2 and dephosphorylated by two S1P phosphatases or irreversibly degraded by a lyase. We recently showed that Toll-like receptor (TLR)4-induced IL-12p70 is selectively counter regulated by SphK1 and extracellular S1P/S1PR1. Others demonstrated that specific SphK1-dependent binding of intracellular S1P to TRAF2 enhances TNF signaling. In an ongoing investigation to determine the influence of extra- and intracellular S1P on dendritic cell signaling our experiments revealed that activation of TLR4 by lipopolysaccharide dose and time dependently decreased S1P lyase mRNA expression of murine bone marrow-derived dendritic cells by up to 70%. This set of realtime PCR data was further confirmed by semi-quantitative RT-PCR using exon-specific primers for murine sgpl1. Systematic analysis with dose-optimized ligands of TLRs 1/2, 5, 2/6, 7/8 and TLR9 showed a differential pattern of S1P lyase down regulation with concomitant increase of intracellular S1P. Although S1P lyase defcient mice are immune compromised, we found that TLR-induced transient S1P lyase downregulation resulted in a TLR adaptor-dependent upregulation of IL-12p70, IL-23 and IL-6 expression on mRNA and protein level. Further experiments including cell compartment-specific quantification of S1P, hexadecenal and, possibly counter regulatory, sphingolipid enzymes are necessary to understand the role of sphingolipids in DC.
Sialylated ligands interact in cis to modulate PILRα inhibitory receptor in myeloid cells (P1358)
Authors: Sun Yonglian , Senger Kate , Sebrell Andrew , Sai Tao , Mazloom Anita , Chinn Yvonne , Luis Elizabeth , Zarrin Ali 
Published: January 2023

Abstract
Paired Ig-like type 2 receptor alpha (PILRα) is an inhibitory receptor expressed in myeloid cells. We show that an evolutionary conserved arginine-containing domain is critical for PILRα interaction with its sialylated ligands. In addition, PILRα is pre-engaged with its ligands in cis on the surface of primary cells and dissociation of PILRa-ligand interactions by sialidase-A treatment unmasks PILRα to bind soluble ligands. At the cellular level, the engagement of PILRα with monoclonal antibody suppresses the production of proinflammatory cytokines. Our data provides novel insights into nature of PILRα interactions and means to modulate the immune response by agonizing this inhibitory pathway.
Functionally distinct Gata3/Chd4 complexes coordinately establish Th2 cell identity. (P1340)
Authors: Hosokawa Hiroyuki , Tanaka Tomoaki , Kato Miki , Tamaki Yuuki , Nakayama Toshinori 
Published: January 2023

Abstract
Gata3 is a GATA family transcription factor that controls differentiation of naïve CD4 T cells into T helper (Th) 2 cells. However, it is unknown how Gata3 simultaneously activates Th2-specific genes while repressing those of other Th lineages. Here we show that Chd4 (chromodomain helicase DNA-binding protein 4) forms a complex with Gata3 in Th2 cells that both activates Th2 cytokine transcription and represses the Th1 cytokine IFNγ. We define a Gata3/Chd4/p300 transcriptional activation complex at the Th2 cytokine loci and a Gata3/Chd4-NuRD repression complex at the Tbx21 locus in Th2 cells. We also demonstrated a physiological role for Chd4 in Th2-dependent inflammation in an in vivo model of asthmatic inflammation. Thus, Gata3/Chd4 forms functionally distinct complexes, which mediate both positive and negative gene regulation to facilitate Th2 cell differentiation.
A genomic regulatory element that directs assembly and function of immune-specific AP-1-IRF complexes (P1322)
Authors: Glasmacher Elke , Agrawal Smita , Chang Abraham , Murphy Theresa , Zeng Wenwen , Vander Lugt Bryan , Khan Aly , Ciofani Maria , Spooner Chauncey , Rutz Sascha , Hackney Jason , Nurieva Roza , Escalante Carlos , Ouyang Wenjun , Littman Dan , Murphy Ken , Singh Harinder 
Published: January 2023

Abstract
Interferon regulatory factor 4 (IRF4) and IRF8 regulate B, T, macrophage, and dendritic cell differentiation. They are recruited to cis-regulatory Ets-IRF composite elements by PU.1 or Spi-B. How these IRFs target genes in most T cells is enigmatic given the absence of specific Ets partners. Chromatin immunoprecipitation sequencing in T helper 17 (T(H)17) cells reveals that IRF4 targets sequences enriched for activating protein 1 (AP-1)-IRF composite elements (AICEs) that are co-bound by BATF, an AP-1 factor required for T(H)17, B, and dendritic cell differentiation. IRF4 and BATF bind cooperatively to structurally divergent AICEs to promote gene activation and T(H)17 differentiation. The AICE motif directs assembly of IRF4 or IRF8 with BATF heterodimers and is also used in T(H)2, B, and dendritic cells. This genomic regulatory element and cognate factors appear to have evolved to integrate diverse immunomodulatory signals.
Influence of site of antigen expression in polarised airway epithelial cells on induction of immune responses (P3339)
Authors: Herbert Rebecca , Norimatsu Mari , Kohl Wiebke , Herrler Georg , Iqbal Munir , Taylor Geraldine 
Published: January 2023

Abstract
Bovine respiratory syncytial virus (BSRV) is a major cause of respiratory disease in calves and is closely related to human RSV. Bovine viral diarrhoea virus (BVDV) is responsible for disease that affects the respiratory, reproductive, immune and enteric systems of cattle. These diseases are a huge problem globally for the livestock industry and a mucosally targeted, bivalent vaccine which prevents infection and spread of these viruses would be valuable. We investigated the influence of the site of expression of the BVDV E2 protein on induction of immune responses using recombinant (r)BRSV expressing wild-type and mutant forms of the E2 protein targeted to different sites within polarised epithelial cells. Calves vaccinated intranasally with rBRSV expressing the E2 protein at the basolateral surface induced higher levels of E2-specific serum antibodies than animals vaccinated with rBRSV expressing E2 at the apical membrane, intracellularly or when secreted from cells. Targeting E2 to the basolateral surface also induced E2-specific IgA antibodies in respiratory secretions without compromising RSV-specific responses. Calves vaccinated intranasally with rBRSV expressing E2 targeted to the basolateral surface were completely protected against challenge with BRSV, and were also protected against nasopharyngeal excretion of BVDV. These studies highlight the importance of the site of expression of foreign proteins in polarised epithelial cells on priming of immune responses.
CX3CR1+ intestinal mononuclear phagocytes regulate induction and maintenance of tolerogenic intestinal immune responses (P3343)
Authors: Diehl Gretchen , Galan Carolina , Longman Randy , Egawa Takeshi , Yang Yi , Littman Dan 
Published: January 2023

Abstract
The intestinal immune system must be tolerant towards commensal microorganisms and food while allowing for the induction of inflammatory responses against pathogens. The mechanisms governing this tolerance are not clearly understood, but loss of this balance can result in commensal- or food-mediated inflammation, leading to intestinal damage. The intestine contains many cell types that can initiate and regulate immune responses, and it is unclear what role each plays in maintaining homeostasis. Two main populations of mononuclear phagocytes reside within the intestine. One is defined by expression of the integrin CD103, and has been described as a migratory dendritic cell (DC). The other expresses the chemokine receptor CX3CR1 and has been compared to tissue resident macrophages. In contrast to previous reports, we recently demonstrated that CX3CR1+ cells migrate from the intestine to the mesenteric lymph node, suggesting that they can behave as DCs. We have generated novel mouse strains allowing depletion of each cell population so that their functions can be studied in vivo. We have found that CX3CR1 and not CD103+ cells are critical for the induction and maintenance of tolerogenic immune responses. We have further demonstrated that antigen presentation by CX3CR1+ cells is critical to prime tolerogenic T cells to intestinal antigens in vivo. This supports our hypothesis that CX3CR1+ cells are DCs that regulate induction of tolerogenic immune responses in vivo.
IFN-γ suppresses MUC5AC expression in human airway epithelium through inhibition of ERK1/2 and SP1 (P3349)
Authors: Takizawa Takumi , Oyanagi Takato , Aizawa Akira , Orosoo Solongo , Arakawa Hirokazu 
Published: January 2023

Abstract
Mucous secretion from airway epithelium plays a pivotal role in primary immune response against pathogens which infect the airway. However its excessive secretion can cause obstruction of airways and respiratory failure. Therefore it is vital to understand mechanisms underlying mucous secretion from airway epithelium and develop medical strategy to control the production of mucous. We have developed an in vitro viral-induced mucin production model using human airway epithelial cell line, NCI-H292, and found that TGF-α and double stranded RNA, polyI:C synergistically induce expression of MUC5AC (J Immunol 2009). Here we uncover IFN-γ suppresses transcription of MUC5AC induced by TGF-α and polyI:C in H292 cells and reveal its molecular mechanisms. IFN-γ inhibited activation of ERK1/2 provoked by TGF-a and polyI:C 9-12 hours after stimulation. IFN-γ decreased TGF-α and polyI:C-upregulated SP1 binging to its cognate site of the MUC5AC promoter. By using inhibitors against SP1 and ERK1/2 phosphorylation, we found that ERK1/2 activation and SP1 binding is independent from each other. These findings demonstrate IFN-g suppress dual pathways that are required for MCU5AC expression.
Improved click chemistry demonstrating EdU cell proliferation with GFP expressing cells and R-PE based immunophenotyping. (P3299)
Authors: Deveny Ruth , DeMarco Carolyn , Bradford Jolene , Clarke Scott , Grecian Scott , Singh Upinder , Gee Kyle 
Published: January 2023

Abstract
The current Click-iT® EdU kit, for measuring cell proliferation, cannot be use for the simultaneous detection of EdU, GFP and R-PE fluorescence due to the presence of copper and reactive oxygen species mediated damage to fluorescent proteins. We present modifications to the click reaction resulting in“copper safe” catalysis of the click reaction. Flow cytometry measurements of cell proliferation using Click-iT® EdU are demonstrated to be compatible with immunophenotyping panels using R-PE conjugates and GFP expressing proteins. The basis of the click chemistry improvement is the use of a copper (I) ligand combined with a modified dye azide detection reagent. We optimized components in the improved click reaction which best preserved R-PE fluorescence while obtaining a bright EdU signal. Jurkat cells were pulsed with EdU, labelled with PE conjugated antibodies and then fixed and permeabilized. EdU incorporation was then detected using click chemistry, demonstrating improved detection while maintaining PE signal. Additionally, BacMam transduced cells expressing GFP were treated with cell cycle inhibitors then pulsed with EdU and used to demonstrate GFP and click chemistry compatibility. The modified click reaction is an improvement over the original copper based click reactions and will further enhance the utility of EdU based cell proliferation applications in flow cytometry.
Brilliant UltraViolet™ Dyes: A new set of high sensitivity fluorescence reagents for multicolor flow cytometry with a UV laser (P3301)
Authors: Stall Alan , Gaylord Brent , Liang Yongchao , Uckert Frank , Leonard Barry , Li Haiqing , Tran Lan , Bartholomew Glenn , Chen Yu , Luan Fengjun , Widmann Stephanie 
Published: January 2023

Abstract
While UV lasers have been available for many years, their utility has been mainly restricted to DNA/RNA binding fluorochromes (e.g. DAPI, Hoescht 33342) for studying cell cycle or stem cell side populations. The low fluorescence intensity of standard fluorescent dyes, such as AlexaFluor™ 350 or AMCA, have made them impractical for routine immunological flow analyses. Here we report the development of a novel class of highly fluorescent polymeric reporters which are excitable by a UV (355nm) laser. The introduction of these dyes has the potential to dramatically extend the functionality of the UV laser adding up to 6 totally new colors for multi-color cytometric flow studies. The first Brilliant UltraViolet (BUV) polymer has an excitation maximum near 355nm with emission below 405nm. Cross laser excitation is minimal requiring very little compensation into the Brilliant Violet 421 channel. Furthermore these polymers can serve as the basis for developing a wide range of bright, ultraviolet excitable tandem reagents, which span the entire spectrum from UV to the near IR. Data will be presented to demonstrate how the superior staining performance and unique excitation / emission profiles of these new dyes offer a broader pallet of colors for those designing multi-parameter flow panels. Comparative flow performance will be presented as will multicolor staining panels which highlight their compatibility with conventional flow reagents.
Anti-CD3 antibody treatment induces hypoglycemia and super tolerance to glucose challenge in mice through T cell activation (P5218)
Authors: Xia Chang-Qing , Wan Suigui , Chernatynskaya Anna , Looney Benjamin , Clare-Salzler Michael 
Published: January 2023

Abstract
Anti-CD3 antibody has been used for various immune-mediated disorders through modulating immune responses. However, whether anti-CD3 administration leads to rapid metabolic alternation has not been well investigated. In the current study, we studied how anti-CD3 treatment affected blood glucose levels in mice. We found that anti-CD3 treatment induced immediate reduction of blood glucose as early as 3-4 hours post-administration. Furthermore, we observed that a single dose of anti-CD3 treatment was able to correct hyperglycemia in all nonobese diabetic mice with new-onset diabetes. This glucose-lowering effect was not attributable to major T cell cytokines secreted by anti-CD3 activated T cells. Furthermore, blood glucose levels of NOD-rag-/- mice lacking T cells remained unchanged after anti-CD3 treatment. Of interest, when tested in a normal strain of mice (C57BL/6), the serum levels of C-peptide in anti-CD3-treated animals were significantly lower than those of control animals. Paradoxically, the anti-CD3-treated animals were highly tolerant to the exogenous glucose challenge. In vitro studies demonstrated that anti-CD3 treatment lowered glucose levels in T cell culture media. Further studies showed that anti-CD3 antibody up-regulated GLUT-1 on activated T cells. This study indicates that anti-CD3 therapy-induced hypoglycemia is likely resulted from increased glucose consumption via enhancing glucose transportation into the activated cells induced by anti-CD3 treatment.
IL-21 neutralizing antibody inhibits human TFH proliferation and TFH-mediated maturation of naïve B cells (P5220)
Authors: Hussell Scott , Smith Patricia , Fox Brian , Serikawa Kyle , Levin Steven , Cox Jennifer , Lundsgaard Dorthe 
Published: January 2023

Abstract
The hallmark of T follicular helper (TFH) cells is the ability to help B cells generate humoral immune responses. Recent evidence suggests that aberrant function of TFH cells plays a key role in the generation of autoantibodies, which can inflict autoimmune pathologies. TFH cells are characterized by their unique master regulator (Bcl6), surface marker expression (CXCR5 and ICOS), and production of the pro-inflammatory cytokine interleukin-21 (IL-21). In mice, IL-21 is described as a regulator of TFH cell differentiation and B cell maturation, but its role in human TFH cells remains incompletely understood. In the present study, we sorted TFH subsets from human tonsils or TFH-like cells from human blood to characterize IL-21 production and the functional consequences of blocking IL-21 with a neutralizing antibody. IL-21 was highest in TFHHI cells (CXCR5++ICOS++), detectable in TFHINT cells (CXCR5+ICOS+), and minimal in non-TFH cells. Anti-IL-21 caused a moderate decrease in anti-CD3 stimulated TFH proliferation. Peripheral CXCR5+ TFH-like cells also had elevated IL-21 production, but anti-IL-21 had little effect on TFH-like proliferation. When TFHINT, TFHHI, or TFH-like cells were co-incubated with naïve B cells, anti-IL-21 decreased B cell maturation and Ig production in a dose-dependent manner. Together, these findings indicate that anti-IL-21 inhibits TFH generation and B cell help, and is a promising therapeutic for autoimmune disorders involving autoantibody production.