bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Protein Kinase C alpha regulates RIG-I mediated IRF3 activation through HDAC6 and beta-catenin (158.18)
Authors: Zhu Jianzhong , Sarkar Saumendra 
Published: January 2023

Abstract
RIG-I like receptors (RLR) are key cytoplasmic receptors to recognize viral RNA, and induce type I interferons via transcription factors such as IRF3 and NF-κB. Here we describe a novel signaling pathway involving PKCα, HDAC6 and β-catenin, which is essential for IRF3-mediated gene induction after virus infection. Stable knockdown of PKCα in various human cell lines inhibited Sendai virus-mediated IFN induction and enhanced virus replication. Sendai virus infection activated PKCα, which enhanced HDAC6 activity in a signal-dependent manner. HDAC6 physically interacted with PKCα and virus infection increased the deacetylation activity of HDAC6, which was absent in PKCα knockdown cells. HDAC6-mediated deacetylation of β-catenin enhanced its nuclear translocation and promoter binding, which was also attenuated in PKCα knockdown cells. We show that in the absence of PKCα/HDAC6-mediated β-catenin nuclear translocation, IRF3, although activated, does not bind to its promoter and is unable to support transcription.
Lung natural helper cells are an important source of innate TH2 cytokines (158.2)
Authors: Halim Timotheus , Sun Ann , Takei Fumio 
Published: January 2023

Abstract
Recently, novel innate TH2 cytokine producing lymphocytes termed nuocytes or natural helper cells have been found in the gut-associated mucosa tissues. Similar TH2 cytokine producing innate cells have also been detected in other organs, including the lung, but their functional significance is not well understood. We have identified TH2 cytokine producing innate lymphocytes, termed lung natural helper (NH) cells in B6 mouse lungs and elucidated their role in lung eosinophilia and asthma. Lung NH cells are Lineage-negative but express of Sca-1, c-Kit, CD127 and CD25. Lung NH cell gene expression microarrays indicate that they likely constitute a novel lymphoid lineage. When purified and stimulated in vitro, they produce large amounts of IL3, 4, 5, 13, and IL17A. They also rapidly produce IL5 and IL13 in lung explant cultures stimulated with IL25, an alarmin released by stressed lung epithelial cells. Lung NH cells are present in Rag-/- mice that lack T and B cells but absent in Rag-/-cγ-/- mice. Intranasal administration of protease allergen papain rapidly induces eosinophil infiltration and mucus hypersecretion, which are hallmark asthma symptoms, in the lung of B6 and Rag-/- mice but not in Rag-/-cγ-/- mice. Papain treatment of lung explants also induces IL13 production by lung NH cells. Thus, lung NH cells are unique lymphocytes of the innate immune system and an important source of T cell-independent TH2 cytokines. They likely play an important role in initiating asthma.
Dynamic changes of gene expression in concordance with histone modifications in CD8 T cells after activation (159.2)
Authors: Subedi Kalpana , Araki Yasuto , De Supriyo , Wood William , Sharov Alexei , Zang Chongzhi , Schones Dustin , Lhotsky Brad , Dudekula Dawood , Becker Kevin , Ko Minoru , Peng Weiqun , Zhao Keji , Weng Nan-ping 
Published: January 2023

Abstract
Memory T cells are characterized by their ability to exhibit a rapid response to the recall antigen. Our previous study shows that histone methylation provides a chromatin basis for the rapid transcriptional response of memory CD8 T cells. To further understand how the histone methylation patterns are established and maintained in memory T cells, we conducted a parallel analysis of gene expression changes with histone methylation changes in naïve and memory (central and effector memory cells) CD8 T cells after in vitro stimulation. Naïve and memory CD8 T cells were isolated from normal adult and stimulated in vitro with antibodies against CD3 and CD28. Gene expression changes (microarray) and histone methylation (H3K4me3 and H3K27me3) (ChIP-Seq) were analyzed. We observed substantial changes in gene expression (~25% increase and ~25% decrease of total expressed genes) after 72 hours of stimulation. Similar trends of histone methylation (H3K4me3 and H3K27me3) changes in corresponding genes in CD8 T cells were observed, suggesting a dynamic change of histone methylation in CD8 T cells after activation. Furthermore, we found that the open chromatin of some poised genes in memory CD8 T cells were established in activated naïve CD8 T cells. Together, these results indicate that histone methylation is dynamic after activation in CD8 T cells and suggest that activation-induced change of chromatin in naïve T cells is part of differentiation process to establish memory T cells.
Chemokine receptor CXCR3 facilitates CD8+ T cell differentiation into short-lived effector cells leading to memory degeneration (159.6)
Authors: Kurachi Makoto , Takamura Shiki , Abe Jun , Ueha Satoshi , Matsushima Kouji 
Published: January 2023

Abstract
Strength of inflammatory stimuli during the early expansion phase plays a crucial role in effector and memory cell fate-decision of CD8+ T cells. But it is not known how early lymphocyte distribution after infection impacts this process. Here we demonstrate that chemokine receptor CXCR3 is involved in CD8 T-cell commitment to effector rather than memory fates by regulating T-cell recruitment to an antigen/inflammation site. After systemic viral (VV-OVA) and bacterial (LM-OVA) infection, contraction of CXCR3KO antigen-specific CD8 T cells is significantly attenuated, resulting in massive accumulation of fully functional memory CD8 T cells. Unlike WT cells, CXCR3KO antigen-specific CD8 T cells fail to cluster early after infection at the marginal zone in the spleen, where inflammatory cytokines such as IL-12 and IFNα are abundant, thus receiving relatively weak inflammatory stimuli. Consequently, CXCR3KO CD8 T cells exhibit shortened expression of CD25, and preferentially differentiate into memory precursor effector cells as opposed to WT CD8 T cells. This series of events has important implications for development of vaccination strategies to generate increased numbers of antigen-specific memory CD8 T cells via inhibition of CXCR3-mediated T-cell migration to inflamed microenvironments.
Miz-1 is required to coordinate the pre-TCR-dependent transitional step in DN3/DN4 thymocytes. (160.1)
Authors: Saba Ingrid , Kosan Christian , Möröy Tarik 
Published: January 2023

Abstract
Miz-1 (Myc-interacting zinc finger-1) is a BTB/POZ domain transcription factor that can activate or repress gene transcription. To explore the function of Miz-1, we have generated mice that express a non-functional protein lacking the POZ domain, Miz-1ΔPOZ. These mice show a very small thymus owing to a dramatic reduction of early T cell progenitors and DN4 pre-T cells. DN1-3 cells have higher apoptotic rate indicating that Miz-1 is coordinating survival signals. Miz-1ΔPOZ mice also have a DN3/DN4 transitional block and DN3 cells showed a dramtic up-regulation of the cell cycle regulator p21Waf1. Surprisingly, neither the introduction of a Bcl-2 transgene nor the deletion of p21Waf1 rescued the DN3/DN4 block in Miz-1ΔPOZ mice. The block at the pre-TCR-dependent selection stage rather suggested that Miz-1 might regulate pre-TCR signaling. Although the pre-TCR signaling does not seem to be altered by the expression of a non-functional Miz-1, the intracellular expression of the TCRβ is reduced. Introduction of a rearranged TCR transgene rescued the DN3/DN4 cell numbers and their function in Miz-1ΔPOZ mice. Our data suggest that Miz-1 is required for the transport or the stability of the pre-TCR in order to support the proliferative burst of DN3 cells. Comparative gene expression analysis will determine which are the direct effector genes of Miz-1 and contribute to a better understanding of the critical factors involved in this precise step of T cell development.
The role of germinal centers in T cell receptor revision (160.10)
Authors: Higdon Lauren , Fink Pamela 
Published: January 2023

Abstract
CD4+ T cells in Vβ5 transgenic mice become tolerant to an endogenous superantigen through either deletion or T cell receptor (TCR) revision. In the revision process, T cells downregulate surface Vβ5 expression and undergo RAG-mediated rearrangement and expression of endogenous TCRs. Revision occurs in germinal centers (GCs), suggesting that revising T cells may be follicular helper T cells (Tfh). We are studying whether revising T cells have a Tfh phenotype and whether GC interactions are required for revision. Preliminary data indicate that revising T cells have an RNA phenotype closely resembling that of Tfh and distinct from that of post-revision T cells. Studies on the intracellular and surface phenotype of revising and post-revision T cells are ongoing. The importance of GCs to TCR revision is being analyzed using SAP and CXCR5 null mice. SAP is required for prolonged interactions of B and T cells in the GC, and CXCR5 is required for cellular migration into the follicle. Analyses of mixed chimeras generated using CXCR5 null and wildtype bone marrow donors are ongoing. CXCR5 and SAP null mice have reduced numbers of post-revision T cells, but no reduction in revision intermediates. These results suggest that migration into the follicle and prolonged B-T cell interactions are both required for completion, but not initiation, of TCR revision.
Essential role of IL-12 signaling for NK cell expansion and memory formation during viral infection (160.15)
Authors: Sun Joseph , Bezman Natalie , Beilke Joshua , Lanier Lewis 
Published: January 2023

Abstract
Although natural killer (NK) cells are generally classified as innate immune cells, several recent studies demonstrated that NK cells become long-lived memory cells and contribute to secondary immune responses like T and B cells. However, the precise signals that promote generation of long-lived NK cells are unknown. Using cytokine receptor deficient mice, we show that the pro-inflammatory cytokine IL-12 is indispensible for virus-specific NK cell expansion and generation of memory cells during MCMV infection. In contrast to wildtype NK cells which proliferated robustly and resided in lymphoid and non-lymphoid tissues for months following MCMV infection, IL-12 receptor-deficient NK cells failed to expand and were difficult to detect soon after infection. In the absence of IL-12 signaling, NK cells were also unable to mediate protection following MCMV challenge. We have evidence that a STAT4-dependent, IFN-gamma-independent mechanism contributes toward the generation of memory NK cells during viral infection. Understanding the full contribution of inflammatory cytokine signaling in the NK cell response to viral infection will be of interest for development of vaccines and therapeutics.
Investigating the involvement of Foxo1 in T cell repertoire diversity (160.8)
Authors: Gubbels Bupp Melanie , Horseman Erica 
Published: January 2023

Abstract
Advanced age is associated with increased susceptibility to and mortality from infectious diseases, especially influenza and pneumonia; and vaccination responses in the elderly are diminished. Declining resistance to infection in aging individuals is correlated with a progressive decline in the size and repertoire of the T cell pool. A better understanding of the mechanisms underlying age-related deterioration of T cell immunity could inform therapies that enhance general immune function and vaccination effectiveness in this vulnerable population. The forkhead transcription factor, Foxo1, has recently been identified as a major regulator of naïve T cell homeostasis. Moreover, a Foxo1 homolog, DAF-16, promotes longevity in C. elegans. Therefore, these studies documented the repertoire diversity of splenic CD4+ and CD8+ T cells in mice selectively deficient for Foxo1 in the T cell compartment (Foxo1 cKO mice). Our studies indicate that T cell-specific Foxo1 deficiency impacts TCR diversity in both the CD4+ and CD8+ splenic T cell populations of young mice. These observations suggest the intriguing possibility that in mice, Foxo1 may participate in aging-related changes in T cell diversity.
B cell traffic through skin increases during inflammation (161.13)
Authors: Geherin Skye , Fintushel Sarah , Lee Michael , Alt Carsten , Young Alan , Hay John , Debes Gudrun 
Published: January 2023

Abstract
B cells infiltrate skin in many chronic inflammatory diseases caused by autoimmunity or infection. Despite their potential to contribute to disease processes, skin-associated B cells remain poorly characterized. Here, we find in an ovine granuloma model of cutaneous inflammation, B cells increase during the chronic phase of inflammation in both relative and absolute number in the skin and skin-draining afferent lymph. Surprisingly, these B cells are a heterogeneous population that is phenotypically distinct from the B cell population in lymph nodes with more ‘innate-like’ B cells co-expressing high levels IgM and CD11b. Furthermore, skin B cells have increased MHCII and CD80/86 expression compared to lymph node B cells, suggesting that they are well-suited for T cell activation at the site of inflammation. Additionally, unlike co-isolated T cells, skin B cells are not responsive to ligands of chemokine receptors typically associated with skin homing, implying that they utilize alternative chemokine receptors to migrate to the skin. In summary, our data show that a population of B cells recirculates through uninflamed and inflamed skin, fulfilling a so far unappreciated role in skin immunity.
Antigen-dependent surveillance of the lungs by pathogen-specific CTL prolongs protective cellular immunity after influenza infection. (161.18)
Authors: Lee Young Tae , Wu Tao , Bouchard Keith , Cauley Linda 
Published: January 2023

Abstract
Influenza viruses are segmented negative-strand RNA viruses which do not integrate into the genome of their host and are incapable of latent infection. Although infectious virus is cleared from the lungs within ~7-10dpi we have shown that trace quantities of processed peptide antigen remain in the draining lymph nodes of the respiratory tract for ~2 months and correspond with local changes in the migration patterns of pathogen-specific CTL in the respiratory tract. Prolonged antigen presentation is a common characteristic of infection with multiple strains of influenza virus, but antigen clearance can occur with much faster kinetics after infection with some isolates. Comparisons between these different isolates show that the processed peptide antigens reinforce expression of two homing receptors (CD69 and CD103) in the lungs which help activated virus-specific CD8 T cells colonize the mucosal tissues during a mild inflammatory response. Furthermore, virus-specific CTL which lacked CD103 expression were less efficient in clearing infectious virus from the lungs, than wild type cells, after heterosubtypic challenge. These data indicate that prolonged antigen presentation is required to reinforce local CTL responses in the lungs and thus explains why protective cellular immunity is short-lived.
Targeting the inflammasome: clearance of Methicillin-Resistant Staphylococcus aureus in skin and soft tissue infections (162.14)
Authors: Artlett Carol , Sassi-Gaha Sihem , Purohit Mitali , Rest Richard , Thacker James 
Published: January 2023

Abstract
We reported an endogenously derived inflammasome activating lipopeptide (1-peptidyl-2-arachidonoyl-3-stearoyl glyceride) with the amino acid sequence for the peptide being acALYDKGYTSKEQKDCVGI (acALY18) and determined that the peptide alone was responsible for the biological activity. Inflammasomes are important for the activation of the innate immune response by detection of danger signals in response to pathogen infection and sterile injury. The inflammasomes modulate the activation of IL-1β and IL-18, by controlling the activation of caspase-1 that cleaves these cytokines for secretion. In fibroblasts, the activation of the inflammasome mediated signaling events by acALY18 was inhibited by Z-YVAD(OMe)-FMK (caspase-1 inactivator) and secretion of IL-1β and IL-18 was abolished. Inflammasome activation in primary human fibroblasts suggests that acALY-18 could be prophylactically useful for the prevention of hospital-acquired infections. Therefore, we conducted a pilot study consisting of two cohorts of 30 mice each infected with MRSA +/- 100 μg/Kg acALY18. In both cohorts, acALY18 reduced the pathogen load in the tissues resulting in smaller lesions and an increased healing rate whereas the untreated mice had much larger lesions with a thick, purulent exudate and no signs of healing. This data suggests that in vivo administration of acALY-18 could induce innate immune responses that would be prophylactically useful for the prevention of hospital-acquired infections.
Cellular mechanisms underlying LPS-induced bactericidal activity in Dictyostelium discoideum (162.15)
Authors: Snyder Michelle , Pflaum Katherine , Gerdes Kimberly , Yovo Kossi , Callahan Jennifer , Walk Alexander 
Published: January 2023

Abstract
Cells of the innate immune system detect pathogen-associated molecular patterns (PAMPs) through highly conserved pattern-recognition machinery. The conservation of this machinery allows for its characterization in model organisms. The unique model organism Dictyostelium discoideum can exist as single-celled amoebae that phagocytize bacteria for nutritional uptake. However, it has not been determined if D. discoideum uses pattern-recognition machinery to detect PAMPs. Here we show that D. discoideum mounts a response against the bacterial cell wall PAMP, lipopolysaccharide (LPS). LPS treatment results in an increased clearance of phagoctyzed bacteria by D. discoideum. LPS-induced bactericidal activity appears to be dependent on MAPK and Tir domain-containing protein A (TirA)-mediated pathways. Recent results suggest that increased bactericidal activity upon treatment with LPS may involve the induction and maturation of autophagosomes. We show here, by following the delivery of the autophagosomal marker Atg8 to degradative compartments, that Staphylococcus aureus induces autophagosomal maturation in D. discoideum only upon addition of LPS. We are currently characterizing the signaling pathways underlying bacterial induction of autophagy in D. discoideum. Characterization of the cellular events induced upon microbial pattern recognition in D. discoideum should provide valuable insight into conversed cellular mechanisms underlying microbial detection and killing.
The cytosolic sensors RIG-I and DAI can mediate glial inflammatory responses to neurotropic viruses (162.17)
Authors: Furr Samantha , Grdzelishvili Valery , Marriott Ian 
Published: January 2023

Abstract
The rapid onset of severe neuroinflammation is a defining feature of viral encephalitis. Glial cells are ideally positioned to respond to CNS pathogens and produce potent inflammatory mediators following exposure to neurotropic viruses. However, the mechanisms by which glia perceive viruses remain unclear. Recently the cytosolic proteins RIG-I and DAI have been reported to function as intracellular sensors of RNA and DNA viruses, respectively, but their role in virally-induced neuroinflammation has not been defined. We have shown that primary glial cells express such receptors constitutively and that their expression can be further induced following viral challenge. In the present study we demonstrate that resident CNS cells express these cytosolic pattern recognition receptors in situ and we show that their expression is elevated in murine models of viral encephalitis. Importantly, we have utilized specific ligands for RIG-I and DAI to demonstrate that these viral sensors can mediate the production of inflammatory/neurotoxic mediators by microglia and astrocytes. Furthermore, we have employed siRNA approaches to demonstrate the importance of RIG-I and DAI in such responses to the neurotropic viruses, VSV and HSV-1, respectively. Together, our studies indicate that these novel cytosolic viral sensors may play a critical role in the recognition of viral pathogens and the initiation of the potentially lethal neuroinflammation associated with acute viral CNS infection.
RON receptor tyrosine kinase, a negative regulator of inflammation, is decreased during SIV associated central nervous system disease. (162.18)
Authors: Cary Daniele , Henderson Andrew , Clements Janice 
Published: January 2023

Abstract
Expressed on tissue resident macrophages, the receptor tyrosine kinase, RON, functions to maintain inflammation homeostatisis by activating genes that promote wound repair and resolve inflammation; while repressing genes that perpetuate tissue damage and cell death. Chronic HIV infection is associated with dysregulated inflammation that contributes to organ diseases, and we hypothesize that altered RON expression contributes to the development of HIV associated CNS disease. We utilized a well characterized SIV model in macaques to explore the temporal regulation of RON in the brain during the course of infection. Following prolonged SIV infection, RON expression decreased below levels observed in controls. RON expression inversely correlated with the development of CNS disease; RON was maintained in animals that did not develop CNS disease and was reduced in macaques that demonstrated CNS disease symptoms. Arginase expression was reduced in the brain during late infection whereas expression of the inflammatory genes, interleukin 12p40 and TNFα were elevated. Our data support a model in which during acute SIV infection in the brain, active inflammation is controlled by RON, however, following prolonged infection, RON expression is decreased, genes that quell inflammation are repressed, and inflammatory mediators are induced to directly promote CNS disease.
Altered oral mucosal homeostasis in Type 1 diabetes (162.19)
Authors: Wallet Shannon , Alonso Tess , Lalane Charles , Catalfamo Dana , Neiva Kathleen 
Published: January 2023

Abstract
In type 1 diabetes (T1D) alterations in mucosal barrier function and immunity are implicated in disease pathogenesis. We have reported that TLR2-inducing homeostatic responses are disrupted in oral epithelial cells (HOK) from T1D individuals. The objective of the study was to delineate mechanisms of TLR2-induced homeostasis altered in T1D. miRNA, protein phosphorylation and cytokine expression were evaluated in HOK challenged with TLR2 or TLR4 agonists. Expression of cytokines was evaluated using a multiplex assay. Total RNA was probed for miR146a, mir133, miR9 and miR155 using qPCR. The expression and phosphorylation of MyD88, TRAF6, IRAK1, and IRAK4 along with the expression of PTPN5, PTPN7 and PTPRR were quantified using western blot. In HOK from non-diabetic participants, TLR2-induced expression of TGFβ and IL10 in the absence of TNFα, IL6 and IL8 was concomitant with increased expression of miR146a and miR155 as well as PTPN5 and PTPRR along with decreased expression and phosphorylation of TRAF6 and IRAK4 when compared to TLR4 stimulation. Upon TLR2 ligation of HOK from T1D, miR146a, miR155, PPTN5 and PTPRR expression was unaltered when compared to TLR4 ligation. Therefore, miRNA regulation of TLR2-induced homeostatic responses as well as phosphatase regulation of TLR signaling cascades are altered in human T1D HOK resulting in over-expression and phosphorylation of TLR signaling intermediates allowing for exacerbated epithelial mediated inflammatory responses.