bluuebunny/crossref_metadata_2025_split huggingface dataset:
AXL Promotes Zika Virus Infection in Astrocytes by Antagonizing Type I Interferon Signaling Pathway
Authors: Xu Jianqing , Zhang Xiaoyan , Liu Jia 
Published: January 2023

Abstract
Zika virus (ZIKV) is known to be associated with neonate microcephaly and Guillain-Barré syndrome in human adults. Despite the progress on understanding the causal link between ZIKV infection and microcephaly, the life cycle and pathogenesis of ZIKV remains elusive. In particular, recent studies have revealed a controversial role of AXL, a TAM family kinase receptor previously deemed as the entry receptor of ZIKV. In this study, we show that though genetic ablation of AXL protects primary human astrocytes and U-251MG astrocytoma cells from ZIKV infection, AXL knockout (KO) does not block the entry of ZIKV, instead it facilitates the up-regulation of type I interferon (IFN) signaling genes, including interferon regulatory factor 7 (IRF7), a key interferon transcriptional factor, and a number of type I interferon and interferon stimulating genes (ISGs). Knockout of type I IFN receptor a chain (IFNAR1) rescues the vulnerability of AXL KO astrocytes to ZIKV infection. In addition, AXL KO in astrocytes results in the down-regulation of SOCS1 in primary astrocytes and the failure to retain the homeostasis of SOCS1 in astrocyte cell lines, a known inhibitor of type I IFN signaling pathway, thus revealing important roles of AXL in maintaining the homeostasis of SOCS1 and thereby in containing type I interferon signaling pathway. Taken together, our study demonstrates that AXL does not function as the sole, if at all, entry receptor of ZIKV, but instead promotes ZIKV infection in astrocytes by SOCS1-mediated antagonism of type I interferon (IFN) signaling.
Dissemination of HIV-1 from latently infected cells to resting CD4+ T cells requires CD4 and actin remodeling.
Authors: Lan Jie , Li Wei , Shepherd Nicole , Xing Yanyan , Yu Andy 
Published: January 2023

Abstract
The major barrier to HIV-1 eradication is the replication-competent proviruses in long-lived latently infected CD4+ T cells. Current efforts to purge latently HIV-1-infected cells have focused on developing “shock and kill” approaches to force reactivation of the proviruses in these cells to be killed after reactivation of virus gene expression by viral cytopathic effects, host immune responses, or both. Cell-free virus infection and cell-to-cell transmission via the virological synapses (VS) are the two modes of HIV-1 dissemination between CD4+ T cells. Several studies have demonstrated that cell-to-cell spread, in which HIV-1 disseminates through direct contact of infected cells with surrounding uninfected cells, is a far more efficient process than that of cell-free virus infection. In this work, we studied the mechanism of cell-to-cell transmission between primary CD4+ T cells and the HIV-1 latently infected cell line ACH-2. When primary resting CD4+ T cells were co-cultured with ACH-2 cells under latency reversing agent Romidepsin stimulation, about 20.7% cells had been infected without becoming activated. Additionally, blocking with anti-CD4 or anti-gp120 neutralizing antibodies (VRC01) decreased de novo infection, and neither anti-CXCR4 antibodies nor chemokine inhibitors demonstrated the ability to inhibit cell-to-cell transmission. We also found that co-cultured resting CD4+ T cells carried higher levels of active cofilin, the actin-depolymerizing factor, suggesting actin plays a role in VS formation and viral pathogenesis. These results suggest HIV-1 Env gp120 binds with the CD4 receptor, not chemokine coreceptor to form VS during cell-to-cell transmission.
Zika and Dengue Virus Specific and Cross-reactive Memory B Cell Responses
Authors: Andrade Paulina E , Coloma Josefina , Michlmayr Daniela , Balmaseda Angel Lazaro , Harris Eva 
Published: January 2023

Abstract
Zika virus (ZIKV) belongs to the Flaviviridae family and is transmitted to humans by Aedes mosquitoes. Since 2015, ZIKV has spread rapidly to 70 countries, most notably in the Americas, where it co-circulates with other flaviviruses that also cause human disease, such as dengue virus (DENV). DENV is comprised of four serotypes that are conserved 65–70% in amino acid sequence of the envelope protein among the DENV serotypes and conserved 54–59% with ZIKV. The antigenic similarity of ZIKV and DENV has raised important biological concerns regarding the effect of immunological cross-reactivity on protection and potential enhancement of ZIKV and DENV infections and vaccines. To date, the cross-reactivity of ZIKV and DENV B cell responses is not fully understood in the context of natural human infections. Here, we use a novel ELISPOT-based assay designated Quad-Color Fluorospot that allows investigation of the DENV serotype specificity vs. cross-reactivity of the memory B cell (MBC) population at a single-cell level, adding a fifth color to include ZIKV. We analyzed a unique set of peripheral blood mononuclear cells from the Nicaraguan Pediatric Dengue Cohort Study, a prospective study of dengue, chikungunya, and Zika now in its 13th year. Samples were collected ~2 weeks and several months after RT-PCR-confirmed ZIKV infection from children who were previously DENV-immune or DENV-naïve. We also included a set of dengue patients who were ZIKV-naïve. Preliminary results show that despite the antigenic similarity between DENV and ZIKV, MBCs from ZIKV-infected subjects were highly specific to ZIKV, with lesser cross-reactivity to DENV. These studies provide much-needed information on how the human immune response reacts to ZIKV and DENV over time
Global Phosphoproteomic and Structural Analyses of Ebola Virions
Authors: Parry Christian , Ivanov Andrey , Ramanathan Palaniappan , Ilinykh Philipp A. , Lin Xionghao , Ammosova Tatiana , Bukreyev Alexander , Nekhai Sergei 
Published: January 2023

Abstract
Ebola virus causes severe hemorrhagic fevers with high mortality characterized by unchecked viral growth and inflammation with marked suppression of host innate and adaptive immune responses. Ebola virus infects macrophages and dendritic cells preferentially, repressing the development of MHC and antigen presentation. Patients who succumb to Ebola virus disease show little evidence of a humoral immune response. VP35 inhibits critical immune signaling early in infection. We have carried out global phosphoproteomic analysis of Ebola virions produced in monkey and bat cells using high resolution MS/MS. We detected all viral proteins with high coverage and identified novel phosphorylation sites in all seven proteins of each virion type. We compared phosphorylation patterns and validated the results by testing the role of the phosphorylation sites of interferon-modulatory VP35 using mutagenesis, in vivo phosphorylation and minigenome assay. We carried out biophysical analyses, structural modeling and simulations of wildtype versus phosphorylated proteins. The phosphorylation pattern differs between virions grown in monkey cells and those grown in bat cells. Nearly all phosphorylation sites were found to be solvent accessible with the majority in flexible regions. VP30, VP35 and NP were characterized by inherent disorder. Mutagenesis, phosphorylation analysis and minigenome experiments showed that VP35 Ser-210 undergoes phosphorylation and is important for transcription. Ser-210 lies in a linker region connecting the coiled coil oligomerization domain and the interferon inhibitory domain. Our findings point to an important role of VP35 phosphorylation and a means of developing inhibitors as drugs against Ebola virus.
Glucocorticoids Drive Circadian Changes in T-Cell Homing and Response via IL-7 Receptor
Authors: Shimba Akihiro , Ikuta Koichi 
Published: January 2023

Abstract
The immune system is deeply affected by steroid hormones. Glucocorticoids are a group of steroid hormones with strong immunosuppressive effects and widely used in clinical practice. However, whether glucocorticoids physiologically control homeostasis and response of the immune system remains unclear. We found that glucocorticoid receptor up-regulates IL-7 receptor (IL-7R) of T cells by binding to an enhancer of the IL-7R locus, and the induction followed circadian rhythm consistent with circadian change of glucocorticoid production. The circadian regulation of IL-7R supported T-cell survival and redistribution between spleen, peyer’s patch and blood by controlling the expression of a chemokine receptor, CXCR4. CXCR4 upregulation induced T cell migration to CXCL12-positive area in spleen and peyer’s patch. Consequently, T cell accumulation in spleen promoted immune responses against systemic bacterial infection. Furthermore, GR enhanced IL-4 production in Th2 condition and helped B cell activation and class-switch to IgG1. Our results reveal the beneficial role of glucocorticoids in enhancing adaptive immunity, and provide insights how the immune function is influenced by circadian rhythm.
T cell up-regulation of CD127 is associated with reductions in the homeostatic set point of the peripheral T cell pool during malnourishment
Authors: Bupp Melanie R Gubbels , Murphy Sarah , Patrick Kristin , Thoner Timothy , Edwards R. Whitney , Litvin Seth 
Published: January 2023

Abstract
The following study was undertaken to better understand the impact of short-term malnutrition on T cell homeostasis, with particular attention focused on the CD127/IL-7 signaling dynamic of peripheral T cells in mice. We report that the total number of peripheral naïve and memory CD4+ and CD8+ T cells notably declined after one week of mild malnourishment--a time period too short to be entirely due to malnutrition-induced thymic involution. Peripheral malnourished T cells expressed higher levels of the IL-7 receptor component, CD127, and were less sensitive to death-by-neglect as compared to control T cells. Adoptive transfer studies revealed that CD127 expression did not correlate with increased survival in vivo and that all naïve CD8+ T cells upregulated CD127, regardless of initial expression levels. Corticosterone levels were elevated in malnourished mice and this correlated in time with peripheral T cell up-regulation of CD127 and the diminishment of the peripheral T cell pool. Overall, these data suggest a model in which CD127 levels are up-regulated quickly during malnourishment, thereby increasing the scavenge rate of IL-7, and providing a mechanism to rapidly adjust the total number of T cells during malnutrition.
Regulatory T cells exhibit distinct lymph node homing and trafficking kinetics as compared to conventional CD4+ T cells
Authors: Tong Alexander , Forestell Benjamin , Murphy Daniel V. , Nair Aditya , Allen Frederick , Mandl Judith N. , Huang Alex Yee-Chen 
Published: January 2023

Abstract
Regulatory T cells (Tregs) express the canonical marker Foxp3 and are critical for suppressing the immune response in homeostatic and inflammatory conditions. Despite how widely studied CD4+Foxp3+ Tregs are in mice, their physiologic trafficking and scanning behavior of antigen-presenting cells in secondary lymphoid organs (SLOs) have yet to be quantitatively analyzed in the intravital setting. We have previously described the dynamics of T cell trafficking through SLOs and scanning of dendritic cells (DCs), revealing that CD4+ T cells and CD8+ T cells exhibit different transit kinetics through lymph nodes (LNs). On average, CD4+ T cells spend less time scanning for self-peptide/MHC (self-pMHC), dwell shorter in LNs, and egress faster compared to CD8+ T cells. Here we use flow cytometry and 2-photon laser scanning microscopy (2-PLSM) to quantitate the homeostatic trafficking behavior and surveillance strategy of Tregs in LNs and to compare their behavior to conventional T cells (Tconvs). Our data reveal significant differences in Treg versus Tconv homing and transit through peripheral and mesenteric LNs. We find that Tregs with an effector phenotype are preferentially retained in LNs, and complementary transwell assays demonstrate that Tregs have blunted response to CCL21 compared to Tconvs. Finally, we use intravital 2-PLSM to quantify the contribution of self-pMHC recognition to Treg kinetics and scanning of DCs in peripheral and mesenteric LNs, taking advantage of a novel gut SLO stabilization device allowing up to 10 hours of continuous imaging. These results add quantitative data to the emerging paradigm that self-pMHC interactions dynamically control homeostatic Treg retainment and localized suppressive function in LNs.
Development and function of skin-homing invariant natural killer T cells
Authors: Wang WeiBei , Xiong Na 
Published: January 2023

Abstract
Invariant natural killer T (iNKT) cells are innate-like T cells that express restricted T cell receptors (TCR) to recognize self and foreign lipid antigens. Distinct iNKT subsets can quickly produce numerous cytokines such as interferon (IFN)-g (iNKT1), interleukin (IL)-4 (iNKT2), and IL-17 (iNKT17) to regulate immune responses in microbial infection, allergic disease, autoimmune disease and cancer. Different iNKT cell subsets have unique transcription factor profiles such as T-bet, PLZF and RORgt that determine their cytokine-producing abilities. However, mechanisms directing the tissue localization preference of different iNKT cell subsets are not well understood. Using a novel strain of CCR10-knockout (KO)/EGFP-knockin (KI) reporter mice, we found that the skin-homing chemokine receptor CCR10 is highly upregulated in iNKT cells during their thymic development stages. Analysis of cytokine production in stimulated thymic iNKT cells demonstrated that CCR10+ iNKT cells are predominantly iNKT2 cells producing IL-4, implying that iNKT2 cells are preferentially programmed in the thymus to migrate into the skin. Confirming this, CCR10-expressing iNKT2 cells are enriched in the skin at the steady state. Taken together, these findings suggest that intrathymic programming orchestrate generation of skin-homing innate-like iNKT cells with specific functional potentials to provide immediate protection of the border tissue.
Supplementing dams with both arachidonic acid and docosahexaenoic acid has beneficial effects on growth and immune development beyond single fatty acid supplementation
Authors: Hadley Kevin , Guimont-Desrochers Fanny , Bailey-Hall Eileen , Field Catherine J , Yurko-Mauro Karin , Salem Norman 
Published: January 2023

Abstract
Omega-3 long-chain polyunsaturated fatty acids (LCPUFAS) modulate immune cells in vitro and in vivo. This study investigated the effects of enriching the maternal diet with the n-6 and -3 LCPUFAs, arachidonic (20:4n-6, 0.6%wt ARA) and docosahexaenoic acid (22:6n-3, 0.32%wt DHA), or a 2:1 ratio (2ARA:1DHA) on total lipids in milk, total lipids, and immunophenotypes in plasma, lymph nodes, and spleen from isolated immune cells from 28d old pups. From day 15 of gestation to post-partum day (ppd)3, Sprague-Dawley dams were fed a commercial chow. On ppd3 litters were culled and pups (4 males and 2 females) randomly cross-fostered to dams who were randomized to one of the 3 experimental diets resulting in 20 male and 10 female pups/diet group. Dams fed ARA or ARA:DHA had 28–36% more 20:4n-6 in milk and feeding DHA or 2:1 ARA:DHA doubled 22:6n-3 in milk lipids (P&lt;0.05). Feeding 2ARA:1DHA or ARA alone resulted in greater pup weight at weaning (P&lt;0.05). Feeding ARA (-DHA) resulted in lower DHA in plasma and spleen while feeding DHA (-ARA) resulted in higher DHA in plasma (P&lt;0.05). Compared to the 2ARA:1DHA pups, there was general trend for ARA fed pups to have higher and DHA fed pups to have lower total, T helper, T cytotoxic, and B lymphocytes in blood, and spleen. In summary, perinatal supplementation with 2ARA:1DHA, compared to ARA or DHA alone, resulted in a higher content of ARA and DHA in breast milk and tissues and had positive effects on growth. DHA without ARA increased 22:6n-3 in milk, plasma, spleen, and reduced 20:4n-6 in milk. Manipulation of dietary LCPUFAs was reflected by lipid content in tissues, and accompanied by evidence of effects on immunophenotype. These changes suggest functional effects but this remains to be confirmed by future investigations.
Embryonic fate mapping uncovers the critic role of miRNAs in skin-resident γδ T cell ontogeny
Authors: Yao Yi , Liu Queping , Martin Carly Elizabeth , Zhou Li , Mi Qing-Sheng 
Published: January 2023

Abstract
Epidermis-resident γδ T cells (termed dendritic epidermal T cells, DETCs) are the first T cells developing in embryonic thymus. Given lack of a fate mapping tool, DETC ontogeny remains poorly understood. Recently, colony stimulating factor 1 receptor (CSF1R) Cre reporter was used to fate map tissue resident macrophages. To study the role of miR-155 in embryonic resident macrophages, we generated Csf1rCremiR-155GFP mice in which both miR-155 and GFP expressions are induced by Csf1rCre. As expected, the majority of skin macrophages highly expressed GFP. Surprisingly, the epidermal Vγ3+DETCs that emerged at E16.5 were all GFP+ cells, and nearly all fetal thymic γδ T cells were also GFP+, although overexpression of miR-155 did not disturb embryonic macrophages and γδ T cells. This observation was confirmed in Csf1rCreRosa26EGFP mice, suggesting CSF1R promoter driving both embryonic myeloid and lymphoid cell lineages. To further study the role of miRNAs in γδ T cell ontogeny, we next generated Csf1rCreDicerKO mice in which miRNAs are deficient. DETCs were almost completely eliminated in Dicer. KO epidermis at E18.5. The number of thymic Vγ3+ T cells were severely reduced (P &lt; 0.0001) in KO embryos, and the frequency of annexin V+ apoptotic Vγ3+ T cells was raised (P &lt; 0.001). Moreover, CD122+ or CD45RB+ mature Vγ3+ T cells were decreased (P &lt; 0.01) in KO embryos, while immature CD24+Vγ3+ T cells were increased (P &lt; 0.01). Thus, loss of miRNAs contributes to defects on survival and maturation of fetal thymic Vγ3+T cells, leading to DETC deficiency. Overall, this is the first study to demonstrate that Csf1rCre serves as a new tool for studying resident γδ T cell embryonic development and miRNAs regulate DETC ontogeny.
Kruppel-like factor 10 regulates innate-like IL-17+CD27−Vγ4+ γδ T cell development
Authors: Kim Girak , Gu MinJeong , Kim Soo Ji , Han Seung Hyun , Cho Jae-Ho , Yun Cheol-Heui 
Published: January 2023

Abstract
γδ T cells, an important source of innate IL-17 in mouse and human, are known to act critical contributions to host immune responses. However, certain factors that control their development and homeostasis are poorly elucidated. In the present study, we examined the role of zinc finger transcriptional factor, Kruppel-like factor 10 (KLF10) in the development and homeostasis of IL-17-committed CD27− γδ T (γδ27−-17) cells. We found a selective augmentation of Vγ4+ γδ27− cells, but not of other IL-17-producing αβ T cells, with higher IL-17 production in KLF10-deficient mice. Although either cytokine (IL-7 or IL-1β plus IL-23) or T cell receptor (TCR) stimuli could induce Klf10 on γδ T cells, KLF10 inhibited γδ27− cell responsiveness to IL-7 or IL-1β plus IL-23 but not TCR stimuli. Surprisingly, KLF10-deficient CD127hiVγ4+ γδ27−-17 cells expressed CD5, a stable indicator of TCR strength, higher than their wild-type counterparts. This was also observed in mature (CD24loCD44hi) but not in immature (CD24hiCD44lo) Vγ4+ γδ27− cells from the neonatal thymus of KLF10-deficient mice, with enhanced maturation of these subsets, indicating that KLF10 deficiency promoted high-affinity TCR bearing Vγ4+ γδ27− cell maturation. Finally, mixed bone marrow chimera study indicated that intrinsic KLF10 signaling is mandatory to limit Vγ4+ γδ27−-17 cells. Collectively, these results suggest that the development and homeostasis of innate-like Vγ4+ γδ27−-17 cell are dependent on a transcriptional control by KLF10 which is differently involved in cytokine or TCR signaling.
Select targeting of intracellular Cysteine in Toll-Interleukin-1 receptor resistance domains for protection against Influenza.
Authors: Snyder Greg A , Shirey Kari Ann , Brown Lindsey J 
Published: January 2023

Abstract
Regulation of Toll-like receptor (TLR) signaling using small molecule agonists and antagonists is widely sought after for controlling inflammation and disease. Recently, small molecule and TIR-based-decoy-peptide inhibitors targeting intracellular Toll-Interleukin-1 receptor (TIR) resistance domains have been identified and functionally characterized to protect against lethality in animal models of infection, inflammation and disease. We observe multiple instances of targeting, modification or involvement of conserved Cysteine residues within intracellular TIR domains by functionally characterized small molecule and decoy peptide inhibitors. We hypothesize that cysteine interactions among intracellular Toll and Interleukin-1 receptors may possess therapeutic value. We have used molecular modeling, X-ray crystallography and in vitro and in vivo functional characterization to characterize TIR cysteine interactions in molecular detail using previously functionally verified derived small molecule and decoy-peptide inhibitors. As a proof of concept, we have used the small molecule receptor antagonist TAK242, which selectively binds Cys747 located in the intracellular TIR domain of TLR4. We show that intracellular targeting of TLR4 TIR domain cysteine using TAK242 is able block LPS activated TLR4 NF-kB signaling in cells and protects mice against lethal influenza (PR8) infection at a lower dose than the ectodomain TLR4 antagonist Eritoran. Structural analysis shows this Cysteine residue to be highly conserved among other surface receptor TLRs 1,2,4,5,6 and 10. Additionally, surface plasmon resonance binding of cysteine containing TIR-decoy peptides, is sensitive to reduction using 2-Mercaptoethanol.
Lactic acid suppresses LPS-induced cytokine production in vitro and in vivo.
Authors: Caslin Heather , Abebayehu Daniel , Qayum Amina Abdul , Hoeferlin L. Alexis , Chalfant Charles E. , Ryan John J. 
Published: January 2023

Abstract
Sepsis is a considerable health burden worldwide with no molecular-based drug treatments. Following the cytokine storm, a hypoinflammatory phase is observed in patients, characterized by impaired cytokine production and glycolysis in immune cells. Lactic acid levels are associated with mortality in patients; however, any regulatory role of lactic acid is currently unknown. We hypothesized that lactic acid contributes to the late phase of sepsis and is not solely a consequence of bacterial infection. As a product of glycolysis, lactic acid may feedback to inhibit glycolysis and overall energy production. Therefore, our purpose was to examine the effects of lactic acid on LPS-induced cytokine production and glycolysis in vitro and on LPS-induced septic shock in vivo. In bone marrow derived and peritoneal mast cells, lactic acid significantly suppressed cytokine and chemokine production at concentrations ≥ 6mM (IL-6) and 12.5 mM (TNF and MCP-1). These effects were dependent upon pH and MCT-1 transport. Additionally, lactic acid attenuated glucose uptake, lactate production, and the expression of the glycolytic enzyme hexokinase 2 following LPS-activation. Extending our in vitro results, lactic acid significantly suppressed IL-6, TNF-α, and MCP-1 induction in multiple in vivo experiments using LPS-induced septic shock. Interestingly, lactic acid did not affect temperature change or observational score. These findings suggest that elevated lactic acid levels may contribute to reduced cytokine concentrations and impaired immune cell metabolism observed in sepsis patients. This information may improve our understanding of immunosuppression in the late phase of sepsis and could reveal new molecular targets for treatment.