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Synthetic Cationic Helical Polypeptides For The Stimulation Of Antitumour Innate Immune Pathways In Antigen-Presenting Cells, Daeyong Lee, Kristin Huntoon, Yifan Wang, Minjeong Kang, Yifei Lu, Seong Dong Jeong, Todd M Link, Thomas D Gallup, Yaqing Qie, Xuefeng Li, Shiyan Dong, Benjamin R Schrank, Adam J Grippin, Abin Antony, Jonghoon Ha, Mengyu Chang, Yi An, Liang Wang, Dadi Jiang, Jing Li, Albert C Koong, John A Tainer, Wen Jiang, Betty Y S Kim May 2024

Synthetic Cationic Helical Polypeptides For The Stimulation Of Antitumour Innate Immune Pathways In Antigen-Presenting Cells, Daeyong Lee, Kristin Huntoon, Yifan Wang, Minjeong Kang, Yifei Lu, Seong Dong Jeong, Todd M Link, Thomas D Gallup, Yaqing Qie, Xuefeng Li, Shiyan Dong, Benjamin R Schrank, Adam J Grippin, Abin Antony, Jonghoon Ha, Mengyu Chang, Yi An, Liang Wang, Dadi Jiang, Jing Li, Albert C Koong, John A Tainer, Wen Jiang, Betty Y S Kim

Student and Faculty Publications

Intracellular DNA sensors regulate innate immunity and can provide a bridge to adaptive immunogenicity. However, the activation of the sensors in antigen-presenting cells (APCs) by natural agonists such as double-stranded DNAs or cyclic nucleotides is impeded by poor intracellular delivery, serum stability, enzymatic degradation and rapid systemic clearance. Here we show that the hydrophobicity, electrostatic charge and secondary conformation of helical polypeptides can be optimized to stimulate innate immune pathways via endoplasmic reticulum stress in APCs. One of the three polypeptides that we engineered activated two major intracellular DNA-sensing pathways (cGAS-STING (for cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon genes) …


Bacteroides Uniformis-Induced Perturbations In Colonic Microbiota And Bile Acid Levels Inhibit Th17 Differentiation And Ameliorate Colitis Developments, Yiting Yan, Yu Lei, Ying Qu, Zhen Fan, Ting Zhang, Yangbin Xu, Qian Du, Daniel Brugger, Yulin Chen, Ke Zhang, Enping Zhang Aug 2023

Bacteroides Uniformis-Induced Perturbations In Colonic Microbiota And Bile Acid Levels Inhibit Th17 Differentiation And Ameliorate Colitis Developments, Yiting Yan, Yu Lei, Ying Qu, Zhen Fan, Ting Zhang, Yangbin Xu, Qian Du, Daniel Brugger, Yulin Chen, Ke Zhang, Enping Zhang

Student and Faculty Publications

Inflammatory bowel disease (IBD) is associated with gut dysbiosis and can lead to colitis-associated malignancies. Bacteroides uniformis (Bu) regulates animal intestinal homeostasis; however, the mechanism by which it alleviates colitis in mice remains unknown. We investigated the effects of B. uniformis JCM5828 and its metabolites on female C57BL/6J mice with dextran sulfate sodium salt (DSS) induced colitis. Treatment with Bu considerably alleviated colitis progression and restored the mechanical and immune barrier protein expression. Additionally, Bu increased the abundance of the symbiotic bacteria Bifidobacterium and Lactobacillus vaginalis while decreasing that of pathogenic Escherichia-Shigella, and modulated intestinal bile acid metabolism. Bu largely …


The Gpcr-Gαs-Pka Signaling Axis Promotes T Cell Dysfunction And Cancer Immunotherapy Failure, Victoria H Wu, Bryan S Yung, Farhoud Faraji, Robert Saddawi-Konefka, Zhiyong Wang, Alexander T Wenzel, Miranda J Song, Meghana S Pagadala, Lauren M Clubb, Joshua Chiou, Sanju Sinha, Marin Matic, Francesco Raimondi, Thomas S Hoang, Rebecca Berdeaux, Dario A A Vignali, Ramiro Iglesias-Bartolome, Hannah Carter, Eytan Ruppin, Jill P Mesirov, J Silvio Gutkind Aug 2023

The Gpcr-Gαs-Pka Signaling Axis Promotes T Cell Dysfunction And Cancer Immunotherapy Failure, Victoria H Wu, Bryan S Yung, Farhoud Faraji, Robert Saddawi-Konefka, Zhiyong Wang, Alexander T Wenzel, Miranda J Song, Meghana S Pagadala, Lauren M Clubb, Joshua Chiou, Sanju Sinha, Marin Matic, Francesco Raimondi, Thomas S Hoang, Rebecca Berdeaux, Dario A A Vignali, Ramiro Iglesias-Bartolome, Hannah Carter, Eytan Ruppin, Jill P Mesirov, J Silvio Gutkind

Student and Faculty Publications

Immune checkpoint blockade (ICB) targeting PD-1 and CTLA-4 has revolutionized cancer treatment. However, many cancers do not respond to ICB, prompting the search for additional strategies to achieve durable responses. G-protein-coupled receptors (GPCRs) are the most intensively studied drug targets but are underexplored in immuno-oncology. Here, we cross-integrated large singe-cell RNA-sequencing datasets from CD8+ T cells covering 19 distinct cancer types and identified an enrichment of Gαs-coupled GPCRs on exhausted CD8+ T cells. These include EP2, EP4, A2AR, β1AR and β2AR, all of which promote T cell dysfunction. We also developed transgenic mice expressing a chemogenetic CD8-restricted Gαs–DREADD to activate …


Smarcb1 Regulates The Hypoxic Stress Response In Sickle Cell Trait, Melinda Soeung, Luigi Perelli, Ziheng Chen, Eleonora Dondossola, I-Lin Ho, Federica Carbone, Li Zhang, Hania Khan, Courtney N Le, Cihui Zhu, Michael D Peoples, Ningping Feng, Shan Jiang, Niki Millward Zacharias, Rosalba Minelli, Daniel D Shapiro, Angela K Deem, Sisi Gao, Emily H Cheng, Donatella Lucchetti, Cheryl L Walker, Alessandro Carugo, Virginia Giuliani, Timothy P Heffernan, Andrea Viale, Nizar M Tannir, Giulio F Draetta, Pavlos Msaouel, Giannicola Genovese May 2023

Smarcb1 Regulates The Hypoxic Stress Response In Sickle Cell Trait, Melinda Soeung, Luigi Perelli, Ziheng Chen, Eleonora Dondossola, I-Lin Ho, Federica Carbone, Li Zhang, Hania Khan, Courtney N Le, Cihui Zhu, Michael D Peoples, Ningping Feng, Shan Jiang, Niki Millward Zacharias, Rosalba Minelli, Daniel D Shapiro, Angela K Deem, Sisi Gao, Emily H Cheng, Donatella Lucchetti, Cheryl L Walker, Alessandro Carugo, Virginia Giuliani, Timothy P Heffernan, Andrea Viale, Nizar M Tannir, Giulio F Draetta, Pavlos Msaouel, Giannicola Genovese

Student and Faculty Publications

Renal medullary carcinoma (RMC) is an aggressive kidney cancer that almost exclusively develops in individuals with sickle cell trait (SCT) and is always characterized by loss of the tumor suppressor SMARCB1. Because renal ischemia induced by red blood cell sickling exacerbates chronic renal medullary hypoxia in vivo, we investigated whether the loss of SMARCB1 confers a survival advantage under the setting of SCT. Hypoxic stress, which naturally occurs within the renal medulla, is elevated under the setting of SCT. Our findings showed that hypoxia-induced SMARCB1 degradation protected renal cells from hypoxic stress. SMARCB1 wild-type renal tumors exhibited lower levels …


Ambient Oxygen Levels Regulate Intestinal Dysbiosis And Gvhd Severity After Allogeneic Stem Cell Transplantation, Keisuke Seike, Anders Kiledal, Hideaki Fujiwara, Israel Henig, Marina Burgos Da Silva, Marcel R M Van Den Brink, Robert Hein, Matthew Hoostal, Chen Liu, Katherine Oravecz-Wilson, Emma Lauder, Lu Li, Yaping Sun, Thomas M Schmidt, Yatrik M Shah, Robert R Jenq, Gregory Dick, Pavan Reddy Feb 2023

Ambient Oxygen Levels Regulate Intestinal Dysbiosis And Gvhd Severity After Allogeneic Stem Cell Transplantation, Keisuke Seike, Anders Kiledal, Hideaki Fujiwara, Israel Henig, Marina Burgos Da Silva, Marcel R M Van Den Brink, Robert Hein, Matthew Hoostal, Chen Liu, Katherine Oravecz-Wilson, Emma Lauder, Lu Li, Yaping Sun, Thomas M Schmidt, Yatrik M Shah, Robert R Jenq, Gregory Dick, Pavan Reddy

Student and Faculty Publications

The severity of T cell-mediated gastrointestinal (GI) diseases such as graft-versus-host disease (GVHD) and inflammatory bowel diseases correlates with a decrease in the diversity of the host gut microbiome composition characterized by loss of obligate anaerobic commensals. The mechanisms underpinning these changes in the microbial structure remain unknown. Here, we show in multiple specific pathogen-free (SPF), gnotobiotic, and germ-free murine models of GI GVHD that the initiation of the intestinal damage by the pathogenic T cells altered ambient oxygen levels in the GI tract and caused dysbiosis. The change in oxygen levels contributed to the severity of intestinal pathology in …


Loss Of Ubiquitin-Specific Peptidase 18 Destabilizes 14-3-3Ζ Protein And Represses Lung Cancer Metastasis, Zibo Chen, Lin Zheng, Yulong Chen, Xiuxia Liu, Masanori Kawakami, Lisa Maria Mustachio, Jason Roszik, Katherine V Ferry-Galow, Ralph E Parchment, Xin Liu, Thorkell Andresson, Gerard Duncan, Jonathan M Kurie, Jaime Rodriguez-Canales, Xi Liu, Ethan Dmitrovsky Dec 2022

Loss Of Ubiquitin-Specific Peptidase 18 Destabilizes 14-3-3Ζ Protein And Represses Lung Cancer Metastasis, Zibo Chen, Lin Zheng, Yulong Chen, Xiuxia Liu, Masanori Kawakami, Lisa Maria Mustachio, Jason Roszik, Katherine V Ferry-Galow, Ralph E Parchment, Xin Liu, Thorkell Andresson, Gerard Duncan, Jonathan M Kurie, Jaime Rodriguez-Canales, Xi Liu, Ethan Dmitrovsky

Student and Faculty Publications

Cancer metastasis is a major cause of cancer-related mortality. Strategies to reduce metastases are needed especially in lung cancer, the most common cause of cancer mortality. We previously reported increased ubiquitin-specific peptidase 18 (USP18) expression in lung and other cancers. Engineered reduction of USP18 expression repressed lung cancer growth and promoted apoptosis. This deubiquitinase (DUB) stabilized targeted proteins by removing the complex interferon-stimulated gene 15 (ISG15). This study explores if the loss of USP18 reduced lung cancer metastasis. USP18 knock-down in lung cancer cells was independently achieved using small hairpin RNAs (shRNAs) and small interfering RNAs (siRNAs). USP18 knock-down reduced …


Immunological And Hematological Outcomes Following Protracted Low Dose/Low Dose Rate Ionizing Radiation And Simulated Microgravity, Amber M. Paul, Eliah G. Overbey, Willian A. Da Silveira, Nathaniel Szewczyk, Nina C. Nishiyama, Michael J. Pecaut, Sulekha Anand, Jonathan M. Galazka, Xiao Wen Mao Jun 2021

Immunological And Hematological Outcomes Following Protracted Low Dose/Low Dose Rate Ionizing Radiation And Simulated Microgravity, Amber M. Paul, Eliah G. Overbey, Willian A. Da Silveira, Nathaniel Szewczyk, Nina C. Nishiyama, Michael J. Pecaut, Sulekha Anand, Jonathan M. Galazka, Xiao Wen Mao

Publications

Using a ground-based model to simulate spaceflight [21-days of single-housed, hindlimb unloading (HLU) combined with continuous low-dose gamma irradiation (LDR, total dose of 0.04 Gy)], an in-depth survey of the immune and hematological systems of mice at 7-days post-exposure was performed. Collected blood was profiled with a hematology analyzer and spleens were analyzed by whole transcriptome shotgun sequencing (RNA-sequencing). The results revealed negligible differences in immune differentials. However, hematological system analyses of whole blood indicated large disparities in red blood cell differentials and morphology, suggestive of anemia. Murine Reactome networks indicated majority of spleen cells displayed differentially expressed genes (DEG) …


Dormant Pathogenic Cd4(+) T Cells Are Prevalent In The Peripheral Repertoire Of Healthy Mice, Anna Cebula, Michal Kuczma, Edyta Szurek, Maciej Pietrzak, Natasha Savage, Wessam R. Elhefnawy, Grzegorz Rempala, Piotr Kraj, Leszek Ignatowicz Oct 2019

Dormant Pathogenic Cd4(+) T Cells Are Prevalent In The Peripheral Repertoire Of Healthy Mice, Anna Cebula, Michal Kuczma, Edyta Szurek, Maciej Pietrzak, Natasha Savage, Wessam R. Elhefnawy, Grzegorz Rempala, Piotr Kraj, Leszek Ignatowicz

Computer Science Faculty Publications

Thymic central tolerance eliminates most immature T cells with autoreactive T cell receptors (TCR) that recognize self MHC/peptide complexes. Regardless, an unknown number of autoreactive CD4+Foxp3 T cells escape negative selection and in the periphery require continuous suppression by CD4+Foxp3+ regulatory cells (Tregs). Here, we compare immune repertoires of Treg-deficient and Treg-sufficient mice to find Tregs continuously constraining one-third of mature CD4+Foxp3 cells from converting to pathogenic effectors in healthy mice. These dormant pathogenic clones frequently express TCRs activatable by ubiquitous autoantigens presented by class II MHCs on conventional dendritic cells, including selfpeptides that select …


The Trophic Life Cycle Stage Of The Opportunistic Fungal Pathogen Pneumocystis Murina Hinders The Ability Of Dendritic Cells To Stimulate Cd4+ T Cell Responses, Heather M. Evans, Andrew Simpson, Shu Shen, Arnold J. Stromberg, Carol L. Pickett, Beth A. Garvy Oct 2017

The Trophic Life Cycle Stage Of The Opportunistic Fungal Pathogen Pneumocystis Murina Hinders The Ability Of Dendritic Cells To Stimulate Cd4+ T Cell Responses, Heather M. Evans, Andrew Simpson, Shu Shen, Arnold J. Stromberg, Carol L. Pickett, Beth A. Garvy

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The life cycle of the opportunistic fungal pathogen Pneumocystis murina consists of a trophic stage and an ascus-like cystic stage. Infection with the cyst stage induces proinflammatory immune responses, while trophic forms suppress the cytokine response to multiple pathogen-associated molecular patterns (PAMPs), including β-glucan. A targeted gene expression assay was used to evaluate the dendritic cell response following stimulation with trophic forms alone, with a normal mixture of trophic forms and cysts, or with β-glucan. We demonstrate that stimulation with trophic forms downregulated the expression of multiple genes normally associated with the response to infection, including genes encoding …


Abl Kinase Regulation By Braf/Erk And Cooperation With Akt In Melanoma, Aditi Jain, Rakshamani Tripathi, Courtney P. Turpin, Chi Wang, Rina Plattner Aug 2017

Abl Kinase Regulation By Braf/Erk And Cooperation With Akt In Melanoma, Aditi Jain, Rakshamani Tripathi, Courtney P. Turpin, Chi Wang, Rina Plattner

Pharmacology and Nutritional Sciences Faculty Publications

The melanoma incidence continues to increase, and the disease remains incurable for many due to its metastatic nature and high rate of therapeutic resistance. In particular, melanomas harboring BRAFV600E and PTEN mutations often are resistant to current therapies, including BRAF inhibitors (BRAFi) and immune checkpoint inhibitors. Abl kinases (Abl/Arg) are activated in melanomas and drive progression; however, their mechanism of activation has not been established. Here we elucidate a novel link between BRAFV600E/ERK signaling and Abl kinases. We demonstrate that BRAFV600E/ERK play a critical role in binding, phosphorylating and regulating Abl localization and Abl/Arg activation …


Zinc Transporters Ybtx And Znuabc Are Required For The Virulence Of Yersinia Pestis In Bubonic And Pneumonic Plague In Mice, Alexander G. Bobrov, Olga Kirillina, Marina Y. Fosso, Jacqueline D. Fetherston, M. Clarke Miller, Tiva T. Vancleave, Joseph A. Burlison, William K. Arnold, Matthew B. Lawrenz, Sylvie Garneau-Tsodikova, Robert D. Perry Jun 2017

Zinc Transporters Ybtx And Znuabc Are Required For The Virulence Of Yersinia Pestis In Bubonic And Pneumonic Plague In Mice, Alexander G. Bobrov, Olga Kirillina, Marina Y. Fosso, Jacqueline D. Fetherston, M. Clarke Miller, Tiva T. Vancleave, Joseph A. Burlison, William K. Arnold, Matthew B. Lawrenz, Sylvie Garneau-Tsodikova, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

A number of bacterial pathogens require the ZnuABC Zinc (Zn2+) transporter and/or a second Zn2+ transport system to overcome Zn2+ sequestration by mammalian hosts. Previously we have shown that in addition to ZnuABC, Yersinia pestis possesses a second Zn2+ transporter that involves components of the yersiniabactin (Ybt), siderophore-dependent iron transport system. Synthesis of the Ybt siderophore and YbtX, a member of the major facilitator superfamily, are both critical components of the second Zn2+ transport system. Here we demonstrate that a ybtX znu double mutant is essentially avirulent in mouse models of bubonic and pneumonic …


Pneumocystis Infection Alters The Activation State Of Pulmonary Macrophages, Jessica M. Deckman, Cathryn J. Kurkjian, Joseph P. Mcgillis, Theodore J. Cory, Susan E. Birket, Linda M. Schutzman, Brian S. Murphy, Beth A. Garvy, David J. Feola Feb 2017

Pneumocystis Infection Alters The Activation State Of Pulmonary Macrophages, Jessica M. Deckman, Cathryn J. Kurkjian, Joseph P. Mcgillis, Theodore J. Cory, Susan E. Birket, Linda M. Schutzman, Brian S. Murphy, Beth A. Garvy, David J. Feola

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Recent studies show a substantial incidence of Pneumocystis jirovecii colonization and infection in patients with chronic inflammatory lung conditions. However, little is known about the impact of Pneumocystis upon the regulation of pulmonary immunity. We demonstrate here that Pneumocystis polarizes macrophages towards an alternatively activated macrophage-like phenotype. Genetically engineered mice that lack the ability to signal through IL-4 and IL-13 were used to show that Pneumocystis alternative macrophage activation is dependent upon signaling through these cytokines. To determine whether Pneumocystis-induced macrophage polarization would impact subsequent immune responses, we infected mice with Pneumocystis and then challenged them with Pseudomonas aeruginosa 14 …


Radiation Induced Apoptosis Of Murine Bone Marrow Cells Is Independent Of Early Growth Response 1 (Egr1), Karine Z. Oben, Beth W. Gachuki, Sara S. Alhakeem, Mary Kathryn Mckenna, Ying Liang, Daret K. St. Clair, Vivek M. Rangnekar, Subbarao Bondada Jan 2017

Radiation Induced Apoptosis Of Murine Bone Marrow Cells Is Independent Of Early Growth Response 1 (Egr1), Karine Z. Oben, Beth W. Gachuki, Sara S. Alhakeem, Mary Kathryn Mckenna, Ying Liang, Daret K. St. Clair, Vivek M. Rangnekar, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

An understanding of how each individual 5q chromosome critical deleted region (CDR) gene contributes to malignant transformation would foster the development of much needed targeted therapies for the treatment of therapy related myeloid neoplasms (t-MNs). Early Growth Response 1 (EGR1) is a key transcriptional regulator of myeloid differentiation located within the 5q chromosome CDR that has been shown to regulate HSC (hematopoietic stem cell) quiescence as well as the master regulator of apoptosis—p53. Since resistance to apoptosis is a hallmark of malignant transformation, we investigated the role of EGR1 in apoptosis of bone marrow cells; a cell population from which …


Herpes Simplex Virus And Interferon Signaling Induce Novel Autophagic Clusters In Sensory Neurons, Sarah Katzenell, David A. Leib Feb 2016

Herpes Simplex Virus And Interferon Signaling Induce Novel Autophagic Clusters In Sensory Neurons, Sarah Katzenell, David A. Leib

Dartmouth Scholarship

Herpes simplex virus 1 (HSV-1) establishes lifelong infection in the neurons of trigeminal ganglia (TG), cycling between productive infection and latency. Neuronal antiviral responses are driven by type I interferon (IFN) and are crucial to controlling HSV-1 virulence. Autophagy also plays a role in this neuronal antiviral response, but the mechanism remains obscure. In this study, HSV-1 infection of murine TG neurons triggered unusual clusters of autophagosomes, predominantly in neurons lacking detectable HSV-1 antigen. Treatment of neurons with IFN-β induced a similar response, and cluster formation by infection or IFN treatment was dependent upon an intact IFN-signaling pathway. The autophagic …


Coordination Of Rna Polymerase Ii Pausing And 3' End Processing Factor Recruitment With Alternative Polyadenylation, Becky Fusby, Soojin Kim, Benjamin Erickson, Hyunmin Kim, Martha L. Peterson, David L Bentley Jan 2016

Coordination Of Rna Polymerase Ii Pausing And 3' End Processing Factor Recruitment With Alternative Polyadenylation, Becky Fusby, Soojin Kim, Benjamin Erickson, Hyunmin Kim, Martha L. Peterson, David L Bentley

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Most mammalian genes produce transcripts whose 3' ends are processed at multiple alternative positions by cleavage/polyadenylation (CPA). Poly(A) site cleavage frequently occurs cotranscriptionally and is facilitated by CPA factor binding to the RNA polymerase II (Pol II) C-terminal domain (CTD) phosphorylated on Ser2 residues of its heptad repeats (YS2PTSPS). The function of cotranscriptional events in the selection of alternative poly(A) sites is poorly understood. We investigated Pol II pausing, CTD Ser2 phosphorylation, and processing factor CstF recruitment at wild-type and mutant IgM transgenes that use alternative poly(A) sites to produce mRNAs encoding the secreted and membrane-bound forms of …


Borrelia Burgdorferi Reva Significantly Affects Pathogenicity And Host Response In The Mouse Model Of Lyme Disease, Rebecca Byram, Robert A. Gaultney, Angela M. Floden, Christopher Hellekson, Brandee L. Stone, Amy Bowman, Brian Stevenson, Barbara J. B. Johnson, Catherine A. Brissette Sep 2015

Borrelia Burgdorferi Reva Significantly Affects Pathogenicity And Host Response In The Mouse Model Of Lyme Disease, Rebecca Byram, Robert A. Gaultney, Angela M. Floden, Christopher Hellekson, Brandee L. Stone, Amy Bowman, Brian Stevenson, Barbara J. B. Johnson, Catherine A. Brissette

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The Lyme disease spirochete, Borrelia burgdorferi, expresses RevA and numerous outer surface lipoproteins during mammalian infection. As an adhesin that promotes bacterial interaction with fibronectin, RevA is poised to interact with the extracellular matrix of the host. To further define the role(s) of RevA during mammalian infection, we created a mutant that is unable to produce RevA. The mutant was still infectious to mice, although it was significantly less well able to infect cardiac tissues. Complementation of the mutant with a wild-type revA gene restored heart infectivity to wild-type levels. Additionally, revA mutants led to increased evidence of arthritis, …


Role Of The Dna Sensor Sting In Protection From Lethal Infection Following Corneal And Intracerebral Challenge With Herpes Simplex Virus 1, Zachary M. Parker, Aisling A. Murphy, David. A. Leib Aug 2015

Role Of The Dna Sensor Sting In Protection From Lethal Infection Following Corneal And Intracerebral Challenge With Herpes Simplex Virus 1, Zachary M. Parker, Aisling A. Murphy, David. A. Leib

Dartmouth Scholarship

STING is a protein in the cytosolic DNA and cyclic dinucleotide sensor pathway that is critical for the initiation of innate responses to infection by various pathogens. Consistent with this, herpes simplex virus 1 (HSV-1) causes invariable and rapid lethality in STING-deficient (STING(-/-)) mice following intravenous (i.v.) infection. In this study, using real-time bioluminescence imaging and virological assays, as expected, we demonstrated that STING(-/-) mice support greater replication and spread in ocular tissues and the nervous system. In contrast, they did not succumb to challenge via the corneal route even with high titers of a virus that was routinely lethal …


Intracellular Listeria Monocytogenes Comprises A Minimal But Vital Fraction Of The Intestinal Burden Following Foodborne Infection, Grant S. Jones, Kate M. Bussell, Tanya Myers-Morales, Abigail M. Fieldhouse, Elsa N. Bou Ghanem, Sarah E. F. D'Orazio Aug 2015

Intracellular Listeria Monocytogenes Comprises A Minimal But Vital Fraction Of The Intestinal Burden Following Foodborne Infection, Grant S. Jones, Kate M. Bussell, Tanya Myers-Morales, Abigail M. Fieldhouse, Elsa N. Bou Ghanem, Sarah E. F. D'Orazio

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Listeria monocytogenes is a highly adaptive bacterium that replicates as a free-living saprophyte in the environment as well as a facultative intracellular pathogen that causes invasive foodborne infections. The intracellular life cycle of L. monocytogenes is considered to be its primary virulence determinant during mammalian infection; however, the proportion of L. monocytogenes that is intracellular in vivo has not been studied extensively. In this report, we demonstrate that the majority of wild-type (strain EGDe) and mouse-adapted (InlAm-expressing) L. monocytogenes recovered from the mesenteric lymph nodes (MLN) was extracellular within the first few days after foodborne infection. In addition, …


Selective Involvement Of The Checkpoint Regulator Vista In Suppression Of B-Cell, But Not T-Cell, Responsiveness By Monocytic Myeloid-Derived Suppressor Cells From Mice Infected With An Immunodeficiency-Causing Retrovirus, Kathy A. Green, Li Wang, Randolph J. Noelle, William R. Green Jul 2015

Selective Involvement Of The Checkpoint Regulator Vista In Suppression Of B-Cell, But Not T-Cell, Responsiveness By Monocytic Myeloid-Derived Suppressor Cells From Mice Infected With An Immunodeficiency-Causing Retrovirus, Kathy A. Green, Li Wang, Randolph J. Noelle, William R. Green

Dartmouth Scholarship

Inhibition of T-cell responses in tumor microenvironments by myeloid-derived suppressor cells (MDSCs) is widely accepted. We demonstrated augmentation of monocytic MDSCs whose suppression of not only T-cell, but also B-cell, responsiveness paralleled the immunodeficiency during LP-BM5 retrovirus infection. MDSCs inhibited T cells by inducible nitric oxide synthase (iNOS)/nitric oxide (NO), but uniquely, inhibition of B cells was ~50% dependent each on iNOS/NO and the MDSC-expressed negative-checkpoint regulator VISTA. Blockade with a combination of iNOS/NO and VISTA caused additive or synergistic abrogation of MDSC-mediated suppression of B-cell responsiveness.


Apparent Role For Borrelia Burgdorferi Luxs During Mammalian Infection, William K. Arnold, Christina R. Savage, Alyssa D. Antonicello, Brian Stevenson Apr 2015

Apparent Role For Borrelia Burgdorferi Luxs During Mammalian Infection, William K. Arnold, Christina R. Savage, Alyssa D. Antonicello, Brian Stevenson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The Lyme disease spirochete, Borrelia burgdorferi, controls protein expression patterns during its tick-mammal infection cycle. Earlier studies demonstrated that B. burgdorferi synthesizes 4,5-dihydroxy-2,3-pentanedione (autoinducer-2 [AI-2]) and responds to AI-2 by measurably changing production of several infection-associated proteins. luxS mutants, which are unable to produce AI-2, exhibit altered production of several proteins. B. burgdorferi cannot utilize the other product of LuxS, homocysteine, indicating that phenotypes of luxS mutants are not due to the absence of that molecule. Although a previous study found that a luxS mutant was capable of infecting mice, a critical caveat to those results is that bacterial …


Zhx2 Enhances The Cytotoxicity Of Chemotherapeutic Drugs In Liver Tumor Cells By Repressing Mdr1 Via Interfering With Nf-Ya, Hongxin Ma, Xuetian Yue, Lifen Gao, Xiaohong Liang, Wenjiang Yan, Zhenyu Zhang, Haixia Shan, Hualin Zhang, Brett T. Spear, Chunhong Ma Jan 2015

Zhx2 Enhances The Cytotoxicity Of Chemotherapeutic Drugs In Liver Tumor Cells By Repressing Mdr1 Via Interfering With Nf-Ya, Hongxin Ma, Xuetian Yue, Lifen Gao, Xiaohong Liang, Wenjiang Yan, Zhenyu Zhang, Haixia Shan, Hualin Zhang, Brett T. Spear, Chunhong Ma

Microbiology, Immunology, and Molecular Genetics Faculty Publications

We previously reported the tumor suppressor function of Zinc-fingers and homeoboxes 2 (ZHX2) in hepatocellular carcinoma (HCC). Other studies indicate the association of increased ZHX2 expression with improved response to high dose chemotherapy in multiple myeloma. Here, we aim to test whether increased ZHX2 levels in HCC cells repress multidrug resistance 1(MDR1) expression resulting in increased sensitivity to chemotherapeutic drugs. We showed evidence that increased ZHX2 levels correlated with reduced MDR1 expression and enhanced the cytotoxicity of CDDP and ADM in different HCC cell lines. Consistently, elevated ZHX2 significantly reduced ADM efflux in HepG2 cells and greatly increased the CDDP-mediated …


Mcl1 Enhances The Survival Of Cd8+ Memory T Cells After Viral Infection, Jingang Gui, Zhuting Hu, Ching-Yi Tsai, Tian Ma, Yan Song, Amanda Morales, Li-Hao Huang, Ethan Dmitrovsky, Ruth Craig, Edward Usherwood Jan 2015

Mcl1 Enhances The Survival Of Cd8+ Memory T Cells After Viral Infection, Jingang Gui, Zhuting Hu, Ching-Yi Tsai, Tian Ma, Yan Song, Amanda Morales, Li-Hao Huang, Ethan Dmitrovsky, Ruth Craig, Edward Usherwood

Dartmouth Scholarship

Viral infection results in the generation of massive numbers of activated effector CD8+ T cells that recognize viral components. Most of these are short-lived effector T cells (SLECs) that die after clearance of the virus. However, a small proportion of this population survives and forms antigen-specific memory precursor effector cells (MPECs), which ultimately develop into memory cells. These can participate in a recall response upon reexposure to antigen even at protracted times postinfection. Here, antiapoptotic myeloid cell leukemia 1 (MCL1) was found to prolong survival upon T cell stimulation, and mice expressing human MCL1 as a transgene exhibited a skewing …


Caspase-3 Mediates The Pathogenic Effect Of Yersinia Pestis Yopm In Liver Of C57bl/6 Mice And Contributes To Yopm's Function In Spleen, Zhan Ye, Amanda A. Gorman, Annette M. Uittenbogaard, Tanya Myers-Morales, Alan M. Kaplan, Donald A. Cohen, Susan C. Straley Nov 2014

Caspase-3 Mediates The Pathogenic Effect Of Yersinia Pestis Yopm In Liver Of C57bl/6 Mice And Contributes To Yopm's Function In Spleen, Zhan Ye, Amanda A. Gorman, Annette M. Uittenbogaard, Tanya Myers-Morales, Alan M. Kaplan, Donald A. Cohen, Susan C. Straley

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The virulence protein YopM of the plague bacterium Yersinia pestis has different dominant effects in liver and spleen. Previous studies focused on spleen, where YopM inhibits accumulation of inflammatory dendritic cells. In the present study we focused on liver, where PMN function may be directly undermined by YopM without changes in inflammatory cell numbers in the initial days of infection, and foci of inflammation are easily identified. Mice were infected with parent and ΔyopM-1 Y. pestis KIM5, and effects of YopM were assessed by immunohistochemistry and determinations of bacterial viable numbers in organs. The bacteria were found …


Cyclic Di-Gmp-Dependent Signaling Pathways In The Pathogenic Firmicute Listeria Monocytogenes, Li-Hong Chen, Volkan K. Köseoğlu, Zehra T. Güvener, Tanya Myers-Morales, Joseph M. Reed, Sarah E. F. D'Orazio, Kurt W. Miller, Mark Gomelsky Aug 2014

Cyclic Di-Gmp-Dependent Signaling Pathways In The Pathogenic Firmicute Listeria Monocytogenes, Li-Hong Chen, Volkan K. Köseoğlu, Zehra T. Güvener, Tanya Myers-Morales, Joseph M. Reed, Sarah E. F. D'Orazio, Kurt W. Miller, Mark Gomelsky

Microbiology, Immunology, and Molecular Genetics Faculty Publications

We characterized key components and major targets of the c-di-GMP signaling pathways in the foodborne pathogen Listeria monocytogenes, identified a new c-di-GMP-inducible exopolysaccharide responsible for motility inhibition, cell aggregation, and enhanced tolerance to disinfectants and desiccation, and provided first insights into the role of c-di-GMP signaling in listerial virulence. Genome-wide genetic and biochemical analyses of c-di-GMP signaling pathways revealed that L. monocytogenes has three GGDEF domain proteins, DgcA (Lmo1911), DgcB (Lmo1912) and DgcC (Lmo2174), that possess diguanylate cyclase activity, and three EAL domain proteins, PdeB (Lmo0131), PdeC (Lmo1914) and PdeD (Lmo0111), that possess c-di-GMP phosphodiesterase activity. Deletion of all …


Vcam-1/Α4Β1 Integrin Interaction Is Crucial For Prompt Recruitment Of Immune T Cells Into The Brain During The Early Stage Of Reactivation Of Chronic Infection With Toxoplasma Gondii To Prevent Toxoplasmic Encephalitis, Qila Sa, Eri Ochiai, Tomoko Sengoku, Melinda E. Wilson, Morgan Brogli, Stephen Crutcher, Sara A. Michie, Baohui Xu, Laura Payne, Xisheng Wang, Yasuhiro Suzuki Jul 2014

Vcam-1/Α4Β1 Integrin Interaction Is Crucial For Prompt Recruitment Of Immune T Cells Into The Brain During The Early Stage Of Reactivation Of Chronic Infection With Toxoplasma Gondii To Prevent Toxoplasmic Encephalitis, Qila Sa, Eri Ochiai, Tomoko Sengoku, Melinda E. Wilson, Morgan Brogli, Stephen Crutcher, Sara A. Michie, Baohui Xu, Laura Payne, Xisheng Wang, Yasuhiro Suzuki

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Reactivation of chronic infection with Toxoplasma gondii can cause life-threatening toxoplasmic encephalitis in immunocompromised individuals. We examined the role of VCAM-1/α4β1 integrin interaction in T cell recruitment to prevent reactivation of the infection in the brain. SCID mice were infected and treated with sulfadiazine to establish a chronic infection. VCAM-1 and ICAM-1 were the endothelial adhesion molecules detected on cerebral vessels of the infected SCID and wild-type animals. Immune T cells from infected wild-type mice were treated with anti-α4 integrin or control antibodies and transferred into infected SCID or nude mice, and the animals received the same antibody every other …


Intrinsic Innate Immunity Fails To Control Herpes Simplex Virus And Vesicular Stomatitis Virus Replication In Sensory Neurons And Fibroblasts, Pamela C. Rosato, David A. Leib Jun 2014

Intrinsic Innate Immunity Fails To Control Herpes Simplex Virus And Vesicular Stomatitis Virus Replication In Sensory Neurons And Fibroblasts, Pamela C. Rosato, David A. Leib

Dartmouth Scholarship

Herpes simplex virus 1 (HSV-1) establishes lifelong latent infections in the sensory neurons of the trigeminal ganglia (TG), wherein it retains the capacity to reactivate. The interferon (IFN)-driven antiviral response is critical for the control of HSV-1 acute replication. We therefore sought to further investigate this response in TG neurons cultured from adult mice deficient in a variety of IFN signaling components. Parallel experiments were also performed in fibroblasts isolated concurrently. We showed that HSV-1 replication was comparable in wild-type (WT) and IFN signaling-deficient neurons and fibroblasts. Unexpectedly, a similar pattern was observed for the IFN-sensitive vesicular stomatitis virus (VSV). …


Use Of Irf-3 And/Or Irf-7 Knockout Mice To Study Viral Pathogenesis: Lessons From A Murine Retrovirus-Induced Aids Model, Megan A. O'Connor, William R. Green Dec 2013

Use Of Irf-3 And/Or Irf-7 Knockout Mice To Study Viral Pathogenesis: Lessons From A Murine Retrovirus-Induced Aids Model, Megan A. O'Connor, William R. Green

Dartmouth Scholarship

Interferon regulatory factor (IRF) regulation of the type I interferon response has not been extensively explored in murine retroviral infections. IRF-3(-/-) and select IRF-3/7(-/-) mice were resistant to LP-BM5-induced pathogenesis. However, further analyses strongly suggested that resistance could be attributed to strain 129-specific contamination of the known retrovirus resistance gene Fv1. Therefore, caution should be taken when interpreting phenotypes observed in these knockout mice, as strain 129-derived genetic polymorphisms may explain observed differences.


Evidence For Finely-Regulated Asynchronous Growth Of Toxoplasma Gondii Cysts Based On Data-Driven Model Selection, Adam M. Sullivan, Xiaopeng Zhao, Yasuhiro Suzuki, Eri Ochiai, Stephen Crutcher, Michael A. Gilchrist Nov 2013

Evidence For Finely-Regulated Asynchronous Growth Of Toxoplasma Gondii Cysts Based On Data-Driven Model Selection, Adam M. Sullivan, Xiaopeng Zhao, Yasuhiro Suzuki, Eri Ochiai, Stephen Crutcher, Michael A. Gilchrist

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Toxoplasma gondii establishes a chronic infection by forming cysts preferentially in the brain. This chronic infection is one of the most common parasitic infections in humans and can be reactivated to develop life-threatening toxoplasmic encephalitis in immunocompromised patients. Host-pathogen interactions during the chronic infection include growth of the cysts and their removal by both natural rupture and elimination by the immune system. Analyzing these interactions is important for understanding the pathogenesis of this common infection. We developed a differential equation framework of cyst growth and employed Akaike Information Criteria (AIC) to determine the growth and removal functions that best describe …


Epigenetic Dominance Of Prion Conformers, Eri Saijo, Hae-Eun Kang, Jifeng Bian, Kristi G. Bowling, Shawn Browning, Sehun Kim, Nora Hunter, Glenn C. Telling Oct 2013

Epigenetic Dominance Of Prion Conformers, Eri Saijo, Hae-Eun Kang, Jifeng Bian, Kristi G. Bowling, Shawn Browning, Sehun Kim, Nora Hunter, Glenn C. Telling

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Although they share certain biological properties with nucleic acid based infectious agents, prions, the causative agents of invariably fatal, transmissible neurodegenerative disorders such as bovine spongiform encephalopathy, sheep scrapie, and human Creutzfeldt Jakob disease, propagate by conformational templating of host encoded proteins. Once thought to be unique to these diseases, this mechanism is now recognized as a ubiquitous means of information transfer in biological systems, including other protein misfolding disorders such as those causing Alzheimer's and Parkinson's diseases. To address the poorly understood mechanism by which host prion protein (PrP) primary structures interact with distinct prion conformations to influence pathogenesis, …


The Role Of Indoleamine 2,3-Dioxygenase In Lp-Bpm5 Murine Retroviral Disease Progression, Megan A. O'Connor, William R. Green May 2013

The Role Of Indoleamine 2,3-Dioxygenase In Lp-Bpm5 Murine Retroviral Disease Progression, Megan A. O'Connor, William R. Green

Dartmouth Scholarship

Indoleamine 2,3-dioxygenase (IDO) is an immunomodulatory intracellular enzyme involved in tryptophan degradation. IDO is induced during cancer and microbial infections by cytokines, ligation of co-stimulatory molecules and/or activation of pattern recognition receptors, ultimately leading to modulation of the immune response. LP-BM5 murine retroviral infection induces murine AIDS (MAIDS), which is characterized by profound and broad immunosuppression of T- and B-cell responses. Our lab has previously described multiple mechanisms regulating the development of immunodeficiency of LP-BM5-induced disease, including Programmed Death 1 (PD-1), IL-10, and T-regulatory (Treg) cells. Immunosuppressive roles of IDO have been demonstrated in other retroviral models, suggesting a possible …