bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of neutrophils in pulmonary vaso-occlusion during sickle cell disease acute chest syndrome (CAM3P.200)
Authors: Bennewitz Margaret , Gladwin Mark , Sundd Prithu 
Published: January 2023

Abstract
Sickle cell disease (SCD) is a hematological disorder that leads to sickling of red blood cells within the microcirculation. The sickle red blood cells (sRBCs) are not only less deformable, but also express α4β1, ICAM-4, Sialyl Lewis X and glycolipids not expressed on non SCD-RBCs. These rigid sRBCs can get sequestered in the microcirculation to cause painful vaso-occlusive crisis (VOC) in SCD patients. In the lung, VOC can contribute to acute chest syndrome, which is a form of acute lung injury. Several factors including the pro-adhesive sRBCs, the large marginated pool of neutrophils, and the hyper-inflammatory state present in SCD can contribute to pulmonary VOC. Although neutrophil-RBC-endothelium interactions are known to play a role in systemic VOC, the cellular mechanism that drives pulmonary VOC remains unknown. Intravital study of the lung microcirculation of live BERK or Townes SCD mice is conducted using two-photon microscopy. Prior to observation, mice are challenged with lipopolysaccharide or PBS to cause lung inflammation and administered (iv) with fluorescent anti-mouse Gr-1 and Ter-119 antibodies to label circulating neutrophils and RBCs, respectively. Vaso-occlusion is defined as cellular aggregation and stasis of blood flow within the lumen of pulmonary capillaries. Preliminary results reveal that circulating macro-aggregates of neutrophils and RBCs may play a role in pulmonary VOC.
The effect of norepinephrine on CD8 T cell subsets in healthy human adults (CCR3P.215)
Authors: Slota Christina , Weng Nan-ping 
Published: January 2023

Abstract
Chronic exposure to stress has detrimental effects on the adaptive immune response. Studies in vitro show that exposure of norepinephrine (NE), a stress hormone, decreases proliferation and functionality of T cells. T cells consist of several different types of cells and each of them serves distinct functions during an immune response. It is unknown how NE reduces functionality of T cells and whether NE has different impact on different types of T cells. Here, we assessed the effect of NE on CD8 T cell function in humans in vitro. We found that not all subsets of CD8 T cells respond the same to NE exposure; memory cells including central memory (Tcm) and effector memory (Tem) were more significantly affected by NE compared to naïve (Tn) CD8 T cells in terms of gene expression of cytokines (IL-2, IFNG, and TNF) important to proliferation and function in the adaptive immune response. Furthermore, expression of NE receptor, Beta-2 adrenergic receptor (B2AR), was higher in freshly isolated memory CD8 T cells (both Tcm and Tem) compared to Tn CD8 T cells. Together these findings show that memory CD8 T cells are more susceptible to NE induced reduction of cytokine production. Currently we are analyzing the effect of NE on general gene expression in Tcm and Tem cells as well as examining histone modifications in these cytokine loci to determine if NE effect via chromatin changes in CD8 T cells.
CCR4-mediated interactions between thymocytes and thymic dendritic cells are required for complete negative selection to self-antigens. (CCR3P.207)
Authors: Hu Zicheng , Jones Jessica , Ehrlich Lauren 
Published: January 2023

Abstract
Clonal deletion of auto-reactive thymocytes is crucial for establishing central tolerance. To mediate negative selection, thymic epithelial cells and dendritic cells (DCs) present self-antigens to thymocytes. Thymocytes that undergo high avidity TCR-mediated interactions with self-peptide:MHC complexes undergo apoptosis to prevent autoimmunity. DCs have been shown to be essential for negative selection. However, the molecular mechanisms governing interactions between thymocytes and DCs are not well characterized. In this study, we find that a chemokine receptor, CCR4, is required for efficient clonal deletion. CCR4 is expressed by post-positive selection thymocytes; CCR4 ligands are expressed by thymic DCs, suggesting CCR4 signaling could mediate interactions between these cell types. Using bone marrow chimeras, we find that CCR4 deficient polyclonal thymocytes fail to undergo efficient clonal deletion, but increase the differentiation to Tregs. While CCR4 deficient OTII TCR transgenic thymocytes also display defects in clonal deletion to endogenous antigens, they undergo efficient deletion to their high affinity ovalbumin antigen. This suggests that CCR4 is not required for TCR-signaling mediating apoptosis, but is required for efficient interactions with thymic DCs that present rare or low affinity antigens. Consistent with defects in clonal deletion, CCR4 deficient mice are prone to autoimmunity, demonstrating that CCR4 is essential for central tolerance.
CD5-CK2 binding domain regulates TCR signals and apoptosis during thymic development. (HEM4P.232)
Authors: Mier Aguilar Carlos Alberto , Raman Chander , Soldevila Gloria 
Published: January 2023

Abstract
CD5 has been previously shown to play an important role in thymic development by downregulating TCR signaling. The receptor contains two major signaling domains in its cytoplasmic tail. The first domain is a functional ITIM domain that recruits proteins such as Ras-Gap, PI3K, Zap 70 and others. The second domain is a CKII Binding Domain (CD5-CKII BD), which in peripheral T cells promotes survival, proliferation and Th differentiation. However, the role of these CD5 signaling domains in early T cell development is poorly understood. In this work we determined the function of CD5-CKII BD in differentiation of thymocyte subpopulations, activation of TCR downstream molecules and regulation of apoptosis using a knock-in mouse in which the CK2 BD is selectively ablated (CD5ΔCKII-BD). Our data show that in non TCR-Tg and in OTII TCR-Tg the loss of CD5-CKII signaling results in a decrease in DP populations in proportion and total cell number and an increase in percentage of CD4+ thymocytes. This reduction in DP thymocytes of OTII.CD5ΔCKII-BD mice was associated with increase in antigen-induced acute activation of ERK phosphorylation relative to OTII.wild-type mice. Additionally, DP and CD4+ thymocytes in CD5ΔCKII-BD mice had increased apoptosis along with elevated levels Caspase 3. Collectively, these results demonstrate that CD5-CKII BD is an important regulator of TCR signals during thymic development and also is a major regulator of the apoptotic events in the thymus.
Peroxisome proliferator-activated receptor-gamma expression in dendritic cells determines immune tolerance versus immune activation (HYP6P.256)
Authors: Khare Anupriya , Chakraborty Krishnendu , Raundhal Mahesh , Morse Christina , Ray Prabir , Ray Anuradha 
Published: January 2023

Abstract
Dendritic cells (DCs) play a central role in regulating immune tolerance and activation but the molecular axis within DCs that dictates immune outcome is unknown. We investigated the role of Peroxisome proliferator-activated receptor-gamma (PPARγ) in DCs in establishment of immune tolerance in the airways using an experimental model. Using mice with selective deletion of PPARγ in CD11c+ cells (PPARγΔ) to ablate PPARγ expression in DCs, we show that DC-specific PPARγ expression exerts a dual role whose collective goal in response to inhaled antigen is to not only promote de novo Foxp3 expression in T cells but to actively dampen T effector cell development. We demonstrate that PPARγ plays a crucial role in enhancing aldh1a2 expression in lung CD103+ DCs under tolerogenic conditions and when tolerized PPARγΔ mice were antigen-challenged, a complete loss of immune tolerance with increased neutrophil-dominated airway inflammation was observed. Absence of PPARγ promoted the expression of multiple pro-inflammatory cytokines such as IL-6 and IL-23 in DCs, limited Foxp3 induction but augmented IL-17 production in T cells with significant increase in the frequency of dual Foxp3+RORγt+ CD4+ T cells in PPARγΔ mice. In summary, our study identifies PPARγ as a central regulator in DC-mediated programming of the Foxp3/RORγt balance in CD4+ T cells dictating tolerance versus inflammation upon antigen provocation.
ILC2 contribute to ozone-induced airway hyperresponsiveness in obese mice (HYP6P.266)
Authors: Mathews Joel , Wurmbrand Allson , Umetsu Dale , Shore Stephanie 
Published: January 2023

Abstract
Many obese asthmatics have non atopic asthma, but the mechanistic basis is poorly understood. Ozone (O3), a common air pollutant, is an asthma trigger that causes airway hyperresponsiveness (AHR) and neutrophilic inflammation. O3-induced AHR and neutrophilia are augmented in obese vs lean mice. Innate lymphoid cells type 2 (ILC2) may be driving these responses. To address this hypothesis, lean WT and obese db/db mice were exposed to room air or O3 (2 ppm) for 3 h. 24 h later, we measured AHR and performed bronchoalveolar lavage (BAL). BAL IL-5, IL-13 and IL-33 were increased by O3 in obese but not lean mice. IL-5 and IL-13 can drive AHR and are secreted by ILC2. IL-33 signaling through ST2 drives activation of ILC2. Therefore, we pretreated db/db mice with ST2 blocking antibody (provided by Dirk Smith, Amgen) prior to O3 exposure. Blocking ST2 decreased O3-induced AHR, baseline lung mechanics, neutrophilia and BAL IL-5 in db/db mice. Anti-IL-13 also decreases BAL neutrophils and lung mechanics in obese mice after O3. IL-23, IL-7, IL-22, and IL-17A were also increased by O3 in obese mice, suggesting the possible involvement of ILC3, a cell activated by IL-7 and IL-23 that secretes IL-17A and IL-22. Blocking IL-17A in a separate cohort also decreased O3 induced AHR and neutrophilia in obese mice. Taken together, our data indicate that obese mice exposed to O3 have increased activation of ILC2 and ILC3 and that these cells are driving the asthma phenotype in these mice.
Limited dependence of IL-4-regulated keratinocyte differentiation and gene expression on STAT6 (HYP6P.261)
Authors: Serezani Ana Paula , Bozdogan Gunseli , Walsh Daniel , Krishnamurthy Purna , Sehra Sarita , Goenka Shreevrat , Spandau Dan , Kaplan Mark 
Published: January 2023

Abstract
Epidermal Differentiation Complex (EDC) genes are critical for barrier function in the skin, and Th2 cytokines that promote allergic inflammation inhibit EDC gene expression in keratinocytes. To further define the effects of the atopic immune response on keratinocyte differentiation, we investigated IL-4-mediated changes in gene expression in human keratinocytes via RNA-seq. Human keratinocytes were differentiated for 2 days with calcium chloride and then stimulated with IL-4 for 24 hours, or keratinocytes were differentiated with calcium chloride and chronically stimulated with IL-4 for 5 days. At day 2, IL-4 increased expression of genes associated with cell cycle, and decreased expression of genes involved with cell adhesion. At day 5 of differentiation, IL-4-stimulated keratinocytes showed increased expression of genes involved with cell projection and adhesion, and decreased expression of genes that participate in wound repair, epidermis development and host defense. STAT6 inhibition by siRNA significantly altered the expression of less than 20% of genes induced by IL-4. Thus, although IL-4 dramatically alters keratinocyte gene expression and differentiation, only a subset of this response is dependent upon STAT6, and eliminating STAT6 expression has IL-4-independent changes in gene expression. This suggests that keratinocyte gene regulation by IL-4 requires additional molecular pathways.
The IL-17-independent role of IL-23 in severe asthma (HYP7P.300)
Authors: Manni Michelle , Mandalapu Sivanarayana , McHugh Kevin , Alcorn John 
Published: January 2023

Abstract
Asthma is a common respiratory disease affecting approximately 300 million people worldwide with no current preventions or cures. Th17 cells are known to be influential in asthma pathogenesis, especially in asthmatics with severe disease that fail to respond to glucocorticoid therapy. Interleukin-23 is critical for the maintenance and full acquisition of Th17 cells, but very little is known about its direct effects outside of IL-17 signaling. This study seeks to investigate novel mechanisms by which IL-23 regulates allergic airway disease. To do this, BALB/c SCID and Rag2-/-γc-/- mice were treated with adenoviral IL-23 or control and airway disease was assessed 3 days later. Preliminary data show that exogenous IL-23 induced airway neutrophilia and pulmonary expression of genes related to asthma pathogenesis and Th17-related cytokines and chemokines, while it increased airway resistance in response to methacholine and decreased lung compliance in BALB/c SCID mice. Further, IL-23 induced airspace inflammation and production of Th17-related cytokines and chemokines, while not impacting lung function in Rag2-/-γc-/- mice. This work suggests a novel role for IL-23 in airway disease as IL-23 itself could induce inflammation, which was predominately neutrophilic, in mice regardless of immune status. More significantly, IL-23 was also shown to modulate pulmonary expression of extracellular matrix-related proteins in these mice, which is currently under investigation.
Development of house dust mite-induced allergic airway disease in a murine model of sickle cell disease is associated with decreased regulatory cells and increased pulmonary pathology (HYP7P.283)
Authors: Adami Alexander , Bracken Sonali , Guernsey Linda , Andemariam Biree , Thrall Roger 
Published: January 2023

Abstract
The hematologic disorder sickle cell disease (SCD) is associated with unusually severe allergic asthma. To explore the mechanisms behind this heightened severity, allergic airway disease was induced in transgenic SCD mice and littermate (LM) controls via 2 wks of intranasal exposure to the clinically-relevant allergen house dust mite (HDM). Following final HDM exposure, animals were sacrificed for pathologic and cellular analyses. SCD was associated with nearly two-fold increase in leukocytes (p &lt; 0.05) and more numerous inflammatory foci in the lung tissue as compared to LM controls. The proportion of CD4+Foxp3+ regulatory T cells was significantly reduced in SCD mice versus LM controls in the broncho-alveolar lavage (BAL) (9% vs. 14% of CD4+ T cells, p &lt; 0.05) and lung (9% vs. 14% of CD4+ T cells, p &lt; 0.01) but not in the hilar (lung-draining) lymph node (HLN). Furthermore, the proportion of CD5+ B cells in SCD mice was nearly half that of LM controls in the BAL (p &lt; 0.0001), lung (p &lt; 0.01), and HLN (p &lt; 0.05). Intriguingly, this B cell population includes regulatory B cells that our laboratory has shown to play an important role in murine models of asthma. The dearth of regulatory cells in SCD may influence the increased pathology seen in the lungs of SCD mice and could contribute to the heightened severity of allergic asthma seen in human SCD. Treatment of asthma in SCD could be enhanced through efforts to target these cellular populations.
Silver nanoparticles impair human antimicrobial immune responses (INC6P.353)
Authors: Schwander Stephan , Zhang Junfeng (Jim) , Tetley Teresa , Gow Andrew , Chung Kian Fan , Ryan Mary , Porter Alexandra , Sarkar Srijata 
Published: January 2023

Abstract
Silver (Ag) nanoparticles (NPs) are widely used in consumer products potentially exposing humans via lungs, skin, digestive tract and insertion of medical devices. Therefore, biological risk assessments of Ag NPs are critical. We assessed the effect of Ag NPs [colloidal silver spheres of 20 nm (Ag20) and 110 nm diameters (Ag110) stabilized with either citrate or polyvinlypyrrolidone (PVP)] on human innate immune responses to Mycobacterium tuberculosis (M.tb), a respiratory pathogen that causes TB. Human monocyte-derived macrophages (MDMs), a model for alveolar macrophages, were exposed to multiple Ag NP doses for 4 hours. Ag NPs (at nontoxic concentrations, MTS assay) increased the expression of mRNA encoding IL8 (p&lt;0.05) while decreasing the expression of mRNA encoding IL10 (p&lt;0.05). Co-exposure of MDMs to Ag NPs and M.tb suppressed the M.tb-induced expression of mRNAs encoding IL1B, IL10, and TNFA in an Ag NP concentration-dependent manner (p&lt;0.05). Ag20-citrate and Ag20-PVP showed stronger inhibitory activities than Ag110-citrate and Ag110-PVP. Ag NPs suppressed antimycobacterial immune responses by inhibiting NF-κB target genes including CSF2, CSF3, IL6, IL1A, IL1B and TNFA, components of the pathogen-induced TLR signaling pathway, crucial for innate antimycobacterial host immunity. These observations may be explained by the strong induction (p&lt;0.05) of mRNA encoding Hsp72 following Ag NP exposure. Hsp72 can potentially inhibit M.tb-induced NF-κB activation.
Exocytosis of toxic primary granules by human neutrophils is associated with high surface TRPM2 expression and pinocytosis (INC6P.401)
Authors: Tirouvanziam Rabindra , Forrest Osric , Bowen James , Brown Milton , Ingersoll Sarah 
Published: January 2023

Abstract
Polymorphonuclear neutrophils (PMNs) play a key role in host defense against microbial infection. PMN responses culminate in the mobilization of highly toxic intracellular primary granules toward either the phagosome (during phagocytosis), nucleus (during NETosis), or plasma membrane (exocytosis). Mechanisms regulating the fate of PMN primary granules remain unclear. Here, we studied the dynamics of PMN primary granule exocytosis in two relevant sets of conditions: 1- in vivo migration of blood PMNs into chronically infected airways of patients with cystic fibrosis; 2- in vitro treatment of blood PMNs with latrunculin B and fMLF. Using flow and image cytometry, we show a striking resemblance between these two sets of conditions, with a close association between primary granule exocytosis (based on surface CD63 expression) and increased surface expression of the inflammatory calcium channel TRPM2. In addition, high primary granule exocytosis associates with major membrane rearrangements, as evidenced by the loss of surface phagocytic receptors (e.g., CD16 and CD35) and high pinocytosis (based on Lucifer Yellow uptake), a process previously linked to TRPM2 activation. All the while, exocytosing PMNs maintain their nuclear integrity. Thus, high primary granule exocytosis, surface TRPM2 upregulation and high pinocytosis are a concerted set of events indicative of a functional program in activated PMNs that is distinct from phagocytosis and NETosis.
AIM2 inflammasome is protective in regulating adaptive responses to oxidative stress in the liver (INM6P.410)
Authors: Sun Qian , Billiar Timothy , Scott Melanie 
Published: January 2023

Abstract
Inflammasome activation leads to activation of caspase1 and maturation of IL1β/IL18 in immune cells. Our previous data showed a novel role for caspase1 in hepatoprotection after redox stress by induction of mitochondrial autophagy, and this is independent of IL1β/IL18. Here, we further investigated inflammasome activation pathways after redox stress in liver. Mice deficient in known main inflammasome components NLRP1a, NLRP3, AIM2 or WT control (C57BL/6) mice underwent hemorrhagic shock with resuscitation (HS/R). NLRP3-/- mice had comparable IL18 levels, liver damage and hepatocyte (HC) caspase1-cleavage as WT mice at 6h. Knockdown of NLRP1a significantly suppressed levels of circulating IL-18 (162±21 vs 101±11pg/ml, p&lt;0.01, control vs NLRP1a knockdown) after HS/R, but similar liver damage and HC caspase1 cleavage to control mice. AIM2-/- mice had similar levels of plasma IL18 as control mice (128±15 vs 135±29pg/ml), but significantly elevated liver injury (195±12 vs 995±287 IU/L, p&lt;0.01) after HS/R, similarly to caspase1-/- mice. Similarly, in vitro AIM2-/- HC had decreased beclin1 expression (2.7 fold decrease in comparison with WT HC) and decreased mitochondrial clearance during redox stress as compared with WT cells. Taken together our data suggest that NLRP1-inflammasome regulates caspase1-activation in immune cells after redox stress, but that AIM2-inflammsome regulates caspase1-activation and mitophagy in HC/liver and is hepatoprotective after HS/R.
Reprogramming lipid metabolism primes host antiviral immunity (INM7P.431)
Authors: York Autumn , Argus Joseph , Zhen Anjie , Wu Nicholas , Sun Ren , Kitchen Scott , Bensinger Steven 
Published: January 2023

Abstract
Oxysterols, or oxidized derivatives of cholesterol, have emerged as important regulators of adaptive and innate immunity. However, the molecular mechanisms by which these lipids facilitate host defense remain indeterminate. To better understand how cellular sterol metabolism influences innate immunity, we have generated gain- and loss-of-function macrophages that have key components of sterol homeostasis perturbed. Remarkably, we find that genetic manipulation of sterol biosynthetic capacity, and cellular sterol homeostasis, intrinsically alters its innate immune program. Genetic inhibition of the sterol biosynthetic pathway renders cells intrinsically resistant to pathogen challenge. Conversely, ectopically enforcing a sterol synthetic program renders cells more susceptible to viral infections. Mechanistic studies indicate that disruption of sterol synthesis in macrophages activates an array of host defense pathways, most notably a robust type 1 IFN response and upregulation of the anti-viral proteins MX-1 and MX-2. Current studies are focused on defining how inhibition of the sterol biosynthetic pathway engages anti-viral immunity and determining if this response is broadly applicable to other cell types. These studies provide proof -of-principle evidence that direct manipulation of sterol homeostatic state of a cell is intimately associated with host defense and suggests that metabolic manipulation converts a cell from a permissive to resistant viral immune state.
Roles of viral inclusion bodies in innate immune evasion in infection with a novel bunyavirus (INM8P.441)
Authors: Xing Zheng , Wu Xiaodong , Qi Xian , Liang Mifang , Li Chuan , Cardona Carol , Li Dexin 
Published: January 2023

Abstract
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging febrile illness caused by a novel phlebovirus in the family Bunyaviridae. We have previously shown that innate immunity in host cells was modulated in infected cells and antiviral cytokine induction was suppressed by nonstructural protein NSs of SFTSV. In this study, we analyzed the pattern recognition receptors and the signaling pathways for mounting innate defense against viruses. Through studying virus-host interactions, we have explored the strategy exploited by SFTSV to evade host antiviral responses. We found that NSs can form inclusion bodies in infected cells. Viral inclusion bodies (IBs), which are accumulated aggregates of viral proteins, are commonly formed during viral replication in infected cells, but their role in viral immune evasion has barely been explored. Interestingly NSs interacted with multiple players in the signaling pathways. Through interacting with tank-binding kinase 1 (TBK1), NSs was able to sequester the IKK complex, including IKKε and IRF3 into IBs, albeit NSs did not interact with IKKε or IRF3 directly. In the presence of NSs, IRF3 could still be phosphorylated, but p-IRF3 was trapped into cytoplasmic IBs in SFTSV-infected cells; consequently, IFN-β induction was reduced and viral replication enhanced. Sequestering IKK complex, active IRF3, and other signaling molecules into viral IBs resulting in a reduced IFN response, is a novel mechanism for viruses to evade innate immunity.