bluuebunny/crossref_metadata_2025_split huggingface dataset:
Avian IgY antibodies recognize novel Dengue NS1 epitopes with the ability to neutralize Dengue 2 virus infection in vitro and in vivo
Authors: O’Donnell Kyle Lee , Espinosa Diego , Nilles Matthew L , Harris Eva , Bradley David 
Published: January 2023

Abstract
Dengue virus (DENV) causes 96 million infections worldwide resulting in 500,000 cases of Dengue Hemorrhagic Fever (DHF) and 22,000 deaths. The severity of DENV infection is greatly enhanced by antibody dependent enhancement (ADE); increased viral load due to increased monocyte opsonization by non-neutralizing low avidity Abs from a previous infection with a different DENV serotype or secondary flavivirus infection. We have previously demonstrated that polyclonal avian anti-DENV-2 IgY ameliorates DENV infection in mice without inducing ADE. The whole polyclonal anti-DENV-2 IgY preparation contained distinct populations of IgY that recognized numerous epitopes of the envelope, membrane, and non-structural (NS) DENV proteins. We report here that two purified pools of anti-DENV-2 IgY with specificity for two different regions of NS1 had a neutralization capacity equivalent to the whole polyclonal anti-DENV-2 IgY preparation in vitro. We assayed each pool of NS1-specific IgY for the potential to induce ADE and demonstrated that neither pool induced ADE when cells were treated with IgY and challenged with a flavivirus. To determine if these NS1 specific IgY achieved neutralization via reducing vascular leakage, we utilized a trans-endothelial electrical resistance (TEER) assay. Interestingly, treatment with DENV NS1-specific IgY did not reduced vascular leakage in our model system. Final to demonstrate the therapeutic potential of NS1 specific IgY we prophylactically treated IFNAR−/− mice with 150 μg of NS1 specific IgY and saw protective efficacy up to 100% in a lethal dengue challenge. We hypothesize that the neutralizing effect of the NS1 specific IgY is via the antibody disrupting the stability of the viral replication complex.
Glycolipid-peptide vaccination induces liver-resident memory CD8+ T cells that protect against malaria
Authors: Holz Lauren , Chua Yu Cheng , Anderson Regan J , Draper Sarah , Compton Benjamin , Li Jasmine , Kedzierski Lukasz , Wang Zhongfang , Osmond Taryn , Farrand Kathryn , Bertolino Patrick J , Bowen David , Cozijnsen Anton , Mollard Vanessa , McFadden Geoffrey , Caminschi Irina , Lahoud Mireille , Kedzierska Katherine , Turner Stephen John , Godfrey Dale , Hermans Ian , Painter Gavin , Heath William R 
Published: January 2023

Abstract
Liver resident-memory CD8+ T cells (TRM cells) provide important protection against liver-stage Plasmodium infections. Here, we show that a glycolipid-peptide conjugate vaccine designed to be cleaved in vivo to release the NKT cell agonist a-galactosylceramide (a-GalCer), together with a CD8+ T cell malarial epitope, efficiently induced intrahepatic malaria-specific T cells expressing canonical markers of liver TRM (CD69, CXCR6 and CD101). While sterile protection was achieved in a proportion of mice using a single vaccine dose, a combined prime-boost regimen induced higher numbers of liver TRM cells and more robust protection. Improved liver TRM cell generation and sterile immunity using a single dose of the vaccine were obtained in all mice by extending the C-and N-terminal residues of the minimal epitope, and by modifying the linker to enhance a-GalCer release. Our findings describe an ideal synthetic vaccine platform to generate large numbers of liver TRM cells that is potentially valuable for controlling a variety of hepatotropic infections.
Adiposity augments toxicity of mouse cytomegalovirus
Authors: Wang Ziming , Dunai Cordelia , Le Catherine , Murphy William J 
Published: January 2023

Abstract
Obesity, a meta-inflammatory state defined by BMI≥30kg/m2, is reaching pandemic proportions. Generally, the impact of obesity on immune responses is poorly understood. Obesity is associated with chronic low-grade systemic pro-inflammatory cytokines. Similar to aging, obesity can affect immune responses and cause susceptibility to infection and pathology. Cytomegalovirus (CMV) is a prevalent herpes virus that can remain asymptomatic for years but causes significant morbidity and mortality in immunosuppressed patients. Our goal was to evaluate the impact of obesity on immune responses to CMV infection with a focus on toxicity. We reported that systemic immunotherapy results in elevated levels of pro-inflammatory cytokines in obese mice, leading to TNF-mediated pathological responses and death. We hypothesized that obesity will augment toxicity in mouse CMV (MCMV) infection as a consequence of heightened pro-inflammatory cytokine production. C57BL/6 and Balb/c were fed either a 60% fat (DIO) or 10% fat (Control) diet starting at 6-weeks old until 6-months old. DIO mice had significantly more subcutaneous and visceral adipose tissue than control mice assessed by MRI. Although ob/ob mice were fed a regular diet, they were significantly fatter than WT mice. Mice (DIO vs control and ob/ob vs WT) infected with 1–5×104 p.f.u. MCMV were assessed for clinical symptoms, serum cytokines, and survival. We observed that 50% of both DIO and ob/ob mice succumbed starting 2 days post-infection, which was associated with increased pro-inflammatory cytokine production. The augmented toxicity induced by MCMV in obese models demonstrates that adiposity is a critical factor in immune-mediated pathological responses to infections.
A PML-Synonymous Mutation in MuPyV Results in Viral Escape from a Neutralizing Monoclonal Antibody
Authors: Lauver Matthew D , Ren Heather , Goetschius Daniel , Hafenstein Susan , Lukacher Aron 
Published: January 2023

Abstract
Progressive Multifocal Leukoencephalopathy (PML) is a fatal demyelinating brain disease caused by JC polyomavirus (JCPyV). Most individuals are asymptomatically infected with JCPyV, but those with immunological perturbations are at risk of developing PML. PML pathogenesis is closely linked with the emergence of JCPyV mutants bearing mutations in regions of the VP1 major capsid protein that bind host cell receptors; these mutations may mediate immune escape or result in altered cell tropism/neurovirulence. A frequent PML mutation in VP1, S269F, is located in the receptor-binding pocket of the virus capsid. To investigate the effects of the S269F mutation on viral infection and the immune response, we utilized mouse polyomavirus (MuPyV) as a natural pathogen-host model of JCPyV infection. We generated a MuPyV mutant containing a V296F substitution in VP1, which maps to the S269F mutation in JCPyV, to ask whether this mutation on immune evasion and host cell tropism. The MuPyV DNA genome incorporates cellular histones; thus we generated infectious fluorescent MuPyV by infecting a host cell line expressing an H2B histone-GFP protein. Using this fluorescently-labeled virus, we determined that a VP1 monoclonal antibody (mAb), which neutralizes wild type virus, binds the V296F mutant, but is unable to block viral attachment and infection. We are currently generating cryo-EM reconstructions to visualize the interaction of this mAb with the wild type and V296F mutant viruses. This data suggests that this PML-synonymous mutation in MuPyV may allow escape from antiviral humoral immunity.
Whole Genome Evolutionary Fingerprinting Suggests Novel Primate Gene Functions in Evolutionary Arms Races
Authors: Tsu Brian V , Murrell Benjamin , Daugherty Matthew , Wertheim Joel 
Published: January 2023

Abstract
Previous positive selection analyses on primate host restriction factors have helped to elucidate differences in primate adaptation to viral infection. However, many of these studies have been focused on small gene families and genes known or suspected to play a role as primate host restriction factors. With the genome sequencing of numerous primate species, we are now capable of comparing the evolutionary profiles of primate genes across the whole genome. Using these evolutionary profiles as guides, we characterize evolutionary similarities and differences between known primate restriction factors and sets of other genes with diverse functions to provide insight on new candidate restriction factors and the biological pressures that affect them.
Interaction between HIV-1 integrase and viral RNA drives proper virion morphogenesis and is necessary for successful infection
Authors: Elliott Jennifer L , Eschbach Jenna E. , Lawson Dana Q. , Puray-Chavez Maritza , Townsend Dana , Li Wen , Koneru Pratibha , Engelman Alan N. , Kvaratskhelia Mamuka , Kutluay Sebla B. 
Published: January 2023

Abstract
Recent findings indicate a key role for the HIV-1 integrase (IN) enzyme in proper virion morphogenesis which involves its binding to viral RNA. Mutations within the IN C-terminal domain potently block IN-RNA interactions leading to the generation of non-infectious particles with “eccentric” morphology with the viral genomic RNA mislocalized outside the capsid core. Despite containing all the components necessary for replication, such particles cannot successfully infect target cells. Interestingly, mutations within IN at residues outside the RNA-binding site cause similar defects. To determine how multiple mutations within IN can lead to similar defects in virion morphology and viral replication, we characterized a panel of IN mutant viruses for defects in the viral lifecycle. Human monocyte-derived macrophages or cultured cells were infected with IN mutant viruses and viral RNA, DNA, and proteins were analyzed by either immunoblot, qPCR, or confocal microscopy. All of the mutant viruses screened were severely attenuated in infectivity, and encountered a block early after entering target cells. Viral RNA and IN were lost from target cells, and reverse-transcribed viral DNA did not accumulate. These findings support a model in which the viral capsid core is critical for protecting entering viral RNA and replicative enzymes from the host environment.
NLRX1 Facilitates HIV-1 Infection of CD4 T Cells by Promoting Oxidative Phosphorylation
Authors: Guo Haitao , Wang Qi , Wang Li , Rampanelli Elena , Chen Xian , Chanda Sumit , Su Lishan , Ting Jenny P 
Published: January 2023

Abstract
The nucleotide-binding, leucine-rich-repeat-containing protein, NLRX1 is recognized as a host factor which promotes HIV-1 infection of myeloid cells by suppressing HIV-1 reverse transcribed DNA induced and STING-mediated innate immune response. However, the function of NLRX1 in HIV-1 infection of CD4 T cells, the major cells responsible for HIV-1 replication in vivo, is still unrevealed. Here we found NLRX1 still acted as a host factor required for HIV-1 infection of the human T cell line, primary CD4 T cells, and CD4 T cell-reconstituted humanized mice through a mechanism involved in cell intrinsic pathways but not innate immune cytokines. In the perspective of virology, we found NLRX1 facilitated both of the integration of HIV-1 cDNA and HIV-1 LTR-mediated viral gene transcription. By using SILAC-based quantitative proteomics, we characterized that HIV-1 infection-induced expression of genes involved in the electron transport chain (ETC) of mitochondria through an NLRX1 dependent mechanism. Consistent with the proteomics data, HIV-1 infection led to increased oxidative phosphorylation in Jurkat T cell line but not in the counterpart containing shRNAs against NLRX1. In addition, inhibition of oxidative phosphorylation by mitochondrial complex I inhibitors suppressed HIV-1 infection in Jurkat cells, while forcing expression of genes involved in ETC rescued the deficiency of HIV-1 replication in NLRX1-deficient cells. Importantly, treating humanized mice with FDA-approved drug, metformin which targets mitochondrial complex I, significantly reduced HIV-1 viral load. This study demonstrated the potential of targeting NLRX1 and applying metformin in suppressing HIV-1 replication in patients.
Sphingosine Kinase 2 mediates LCMV-induced CD4+ T cell suppression and instigates viral persistence while preventing immunopathology
Authors: Studstill Caleb J , Pritzl Curtis J. , Seo Young-Jin , Kim Dae Y. , Xia Chuan Z. , Wolf Jennifer J , Vijayan Madhuvanthi , Hahm Bumsuk 
Published: January 2023

Abstract
Viruses often establish persistent infections by causing dysfunctional T cell responses. Little is known about the role of sphingosine kinase 2 (SphK2) in the immune response to viral infections; even though, its enzymatic product, sphingosine 1-phosphate, is well-known to regulate versatile cellular processes. In this work, we demonstrate that during lymphocytic choriomeningitis virus clone 13 (LCMV Cl 13) infection in mice, SphK2 functions to limit CD4+ T cell responses, which aids in the establishment of virus-induced immunosuppression and viral persistence. The infection of SphK2-deficient (SphK2−/−) mice with LCMV Cl 13 resulted in kidney disease and ultimately mortality, which was not observed with acute infection by the Armstrong strain of LCMV. Following infection, SphK2−/− mice were shown to have increased LCMV-specific CD4+ and CD8+ T cell responses. Depletion of CD4+ or CD8+ T cells prevented the infection-induced death of SphK2−/− mice, which indicates T cell-mediated immunopathology. With the use of LCMV epitope-specific TCR transgenic mouse lines for adoptive transfer studies, SphK2 was shown to have intrinsic negative function in CD4+ T cells, but not CD8+ T cells. Furthermore, SphK2−/− CD4+ T cells were able to promote endogenous, virus-specific CD8+ T cell responses. Importantly, oral treatment of LCMV Cl 13-infected mice with an SphK2-selective inhibitor increased the number of LCMV-reactive CD4+ and CD8+ T cells, and led to the accelerated termination of LCMV Cl 13 persistence, without causing mortality. Our results suggest that transient SphK2 inhibition is a promising novel immunotherapeutic strategy for the control of persistent viral infections.
A Brazilian Zika virus isolate suppresses type I interferon to establish a sustained infection in immunocompetent mice
Authors: Pardy Ryan D , Richer Martin J 
Published: January 2023

Abstract
Zika virus (ZIKV) is a mosquito-borne pathogen that recently gained international attention following a major epidemic in South and Central America. The most striking aspect of this epidemic was the novel association of ZIKV infection with neurological symptoms, such as fetal microcephaly. In addition, ZIKV may persist in humans for 15- and 42-days post-symptom onset in serum and semen, respectively. Therefore, our objective was to investigate whether recent ZIKV isolates have an enhanced capacity to evade host immunity. To address this objective, we have established an immunocompetent mouse model of ZIKV infection, in which infection with pre-epidemic, early Asian lineage ZIKV isolate (ZIKV-CDN) induces robust type I interferon (IFN) production and prototypical Th1 CD4 and effector CD8 T cell responses. We are now comparing this baseline to the immune response induced by a ZIKV isolate from the Brazilian epidemic (ZIKV-BR). Our data demonstrate a dramatic suppression of type I IFN production during ZIKV-BR infection, which correlates with a severe reduction in the CD8 T cell response. Co-infection reduces the magnitude of the CD8 T cell response when compared to infection with ZIKV-CDN alone, suggesting ZIKV-BR actively interferes with the host immune response. As a result, ZIKV-BR establishes a sustained infection, with high viral loads detected as late as 7 days post-infection. Future studies will aim to determine why less type I interferons are produced, and the impact of ZIKV-BR infection on the CD4 T cell response. Together, our data suggest that contemporary strains of ZIKV have evolved novel ways of countering host immunity, which could explain, at least in part, the increased pathogenicity observed in recent outbreaks.
The Influence of The Lung Virome on Pulmonary B cells
Authors: Aihara Fumiaki , Breen Michael P. , Feng Feng , Fearns Rachel , Mizgerd Joseph P. , Kepler Thomas B. 
Published: January 2023

Abstract
The human microbiome is a complex and diverse environment that is implicated in human health and disease. Major locations that host a microbiome include the gut, respiratory system, and the urogenital tracts. While there have been steady advances of the effect of our commensal flora in regions such as the gut microbiome, the impact of the pulmonary microbiome, specifically the viral arm of the microbiome (virome), remains unclear and under-researched. Recent studies have shown that pulmonary viruses can influence disease susceptibility to the benefit, or detriment, to the host. Despite increasing evidence that the lung virome influences human health through the immune system, the direct effects on the host immune system remain unclear. We hypothesize that the chronic presence of the lung virome influences the pulmonary B cell repertoire. The constant exposure to pulmonary virus can generate a unique B cell repertoire independent of peripheral B cells that is tailored specifically towards pulmonary viruses. To address this hypothesis, we have utilized a single-cell B cell culture system to amplify human lung-derived memory B cells (MBCs) from limited human donor samples. By analyzing these MBCs at the genetic level by RNA sequencing and protein level by antigen affinity from secreted antibodies, we can begin to understand the impact of the lung virome on the pulmonary B cell repertoire.
Blimp-1 transcriptionally induced by growth factors, TNF-α and TLR ligands inhibits keratinocyte migration and inflammation but enhances cell migration in squamous cell carcinoma
Authors: Lin Wan-Wan , Huang Duen-Yi 
Published: January 2023

Abstract
B lymphocyte-induced maturation protein-1 (Blimp-1) is a transcriptional repressor, and plays a crucial role in the regulation of development and functions of various immune cells. Currently, there is limited understanding about the regulation of Blimp-1 expression and cellular functions in keratinocytes and cancer cells. The aim of the study was to investigate the regulation and functional link between EGFR and Blimp-1 in human epidermal keratinocytes and squamous cell carcinoma (SCC). We found that EGF, PMA, TNF-α, LPS (TLR4 activator) and polyIC (TLR3 activator) can upregulate the protein and mRNA levels of Blimp-1 in NHEK and/or HaCaT cells. This effect of EGF was dependent on PKC, p38, and ERK activation, and Syk is also involved in the action of PMA. Additionally, the stability of Blimp-1 protein was under the control of the proteasome and lysosome degradation systems. PMA, LPS and polyIC also can activate EGFR and Syk in HaCaT cells. In addition, Blimp-1 knockdown enhanced the EGFR-mediated IL8, CXCL5 and IL6 gene expression and keratinocyte migration, but reduced the EGFR-mediated suppression of differentiation marker K10. On the other hand, EGF, TNF-α, TGF-β and PMA could also upregulate Blimp-1 expression in SCC, and EGFR activation by TNF-α and PMA was observed. Unlike the action of Blimp-1 in keratinocytes, Blimp-1 silencing reduces SCC cell migration either in the absence or presence of TNF-α and PMA. Taken together, Blimp-1 can be upregulated by several growth factors, innate immune receptors and PKC signaling pathway. Blimp-1 is a negative regulator of EGF-induced inflammation and migration in keratinocytes, but mediates cell migration in SCC.
Follicular dendritic cell migration is promoted by the expression of matrix metalloproteinase 3 through TNFα-ERK1/2-AP-1 signaling
Authors: Yong-Woo Kim , Pak Hyo-Kyung , Park Chan-Sik 
Published: January 2023

Abstract
Follicular dendritic cells (FDCs) are the major stromal components in the germinal center and are developed and maintained by lymphotoxin α1/β2 and tumor necrosis factor-α (TNFα). These cells have the pivotal role in high-affinity antibody production. However, many functions of FDCs are still unknown, such as its migration. Here, we demonstrate for the first time that TNFα increased matrix metalloproteinase 3 (MMP3) expression in human FDCs and induced migration of these cells. Normal human germinal centers expressed of MMP3, and MMP3 in the FDCs are increased by TNFα. The induction of MMP3 in FDCs is dependent on ERK1/2 activation. TNFα stimulation induced the promoter activity of the AP-1 binding sites in Mmp3 proximal promoter region. The induced expression of MMP3 increased FDC migration and the reduction of MMP3 expression decreased FDC migration. Overall, we identified a novel mechanism for the expression of MMP3 in FDCs to modulate the migration, a process of lymphoid follicle development. Lymphoid follicles are observed in the lesion of many autoimmune and autoantibody-associated diseases, thereby control of TNFα-mediated migration of FDCs may suppress those diseases.
TSPAN33 regulates endocytosis and migration of human B lymphocytes by regulating the plasma membrane tension
Authors: Navarro-Hernandez Itze Cecilia , Acevedo-Ochoa Ernesto , López-Ortega Orestes , Fragoso-Soriano Rogelio , Galván-Hernández Arturo , Antillón Armando , Ortega-Blake Iván , Hernández-Hernández José Manuel , Maravillas-Montero José Luis 
Published: January 2023

Abstract
B lymphocytes develop different immune-related functions apart from differentiating into antibody-secreting cells. These processes are triggered by external stimuli that activate them and induce changes in the physicochemical properties of their plasma membrane. These changes are regulated by the formation of discrete lipid-bilayer compartments, including the tetraspanin-enriched microdomains. Tetraspanins compose a superfamily of transmembrane proteins that establish lateral associations with other molecules, determining its activity. In this study, we identified TSPAN33 as an active player during B lymphocyte cytoskeleton and plasma membrane-related phenomena. By using an overexpression model of TSPAN33 in human Raji cells, we located this protein on different membrane organelles including Golgi and intracellular vesicles as observed by confocal microscopy. Additionally, these cells displayed diminished phagocytic and cell adhesion properties, due to aberrant surface expression of integrins. This phenotype also prove to enhance 2D and 3D migration in response to CCL21. Strikingly, when we evaluated the mechanical plasma membrane response of the cells using atomic force microscopy, during fibronectin-induced spreading, we found that TSPAN33 expression inhibited normal changes in membrane tension and roughness parameters. For that reason, we generate TSPAN33 knock-down cells that showed enhanced adhesive and phagocytic capacities when compared with control cells. Altogether, our data indicate that TSPAN33 represents an inhibitory element of the adhesion and migration of B cells, suggesting also a novel implication of this protein in the regulation of mechanical properties of the plasma membrane.