Medicine and Health Sciences Commons^™

Adjuvanted Fusion Protein Vaccine Induces Durable Immunity To Onchocerca Volvulus In Mice And Non-Human Primates, Nathan M. Ryan, Jessica A. Hess, Erica J. Robertson, Nancy Tricoche, Cheri Turner, Jenn Davis, Nikolai Petrovsky, Melissa Ferguson, William J. Rinaldi, Valerie M. Wong, Ayako Shimada, Bin Zhan, Maria Elena Bottazzi, Benjamin L. Makepece, Sean A. Gray, Darrick Carter, Sara Lustigman, David Abraham

Department of Microbiology and Immunology Faculty Papers

Onchocerciasis remains a debilitating neglected tropical disease. Due to the many challenges of current control methods, an effective vaccine against the causative agent Onchocerca volvulus is urgently needed. Mice and cynomolgus macaque non-human primates (NHPs) were immunized with a vaccine consisting of a fusion of two O. volvulus protein antigens, Ov-103 and Ov-RAL-2 (Ov-FUS-1), and three different adjuvants: Advax-CpG, alum, and AlT4. All vaccine formulations induced high antigen-specific IgG titers in both mice and NHPs. Challenging mice with O. volvulus L3 contained within subcutaneous diffusion chambers demonstrated that Ov-FUS-1/Advax-CpG-immunized animals developed protective immunity, durable for at least 11 weeks. Passive …

Il-11 Induces Nlrp3 Inflammasome Activation In Monocytes And Inflammatory Cell Migration To The Central Nervous System, Maryamsadat Seyedsadr, Yan Wang, Manal Elzoheiry, Sowmya Shree Gopal, Soohwa Jang, Gayel Duran, Inna Chervoneva, Ezgi Kasimoglu, John A. Wrobel, Daniel Hwang, James Garifallou, Xin Zhang, Tabish H. Khan, Ulrike Lorenz, Maureen Su, Jenny P. Ting, Bieke Broux, A M Rostami, Dhanashri Miskin, Silva Markovic-Plese

Department of Neurology Faculty Papers

The objective of this study is to examine IL-11-induced mechanisms of inflammatory cell migration to the central nervous system (CNS). We report that IL-11 is produced at highest frequency by myeloid cells among the peripheral blood mononuclear cell (PBMC) subsets. Patients with relapsing-remitting multiple sclerosis (RRMS) have an increased frequency of IL-11+ monocytes, IL-11+ and IL-11R+ CD4+ lymphocytes, and IL-11R+ neutrophils in comparison to matched healthy controls. IL-11+ and granulocyte-macrophage colony-stimulating factor (GM-CSF)+ monocytes, CD4+ lymphocytes, and neutrophils accumulate in the cerebrospinal fluid (CSF). The effect of IL-11 in-vitro stimulation, examined using single-cell RNA sequencing, revealed the highest number of …

Design And Preclinical Evaluation Of A Universal Sars-Cov-2 Mrna Vaccine, Jane Qin, Ju Hyeong Jeon, Jiangsheng Xu, Laura Katherine Langston, Ramesh Marasini, Stephanie Mou, Brian Montoya, Carolina R Melo-Silva, Hyo Jin Jeon, Tianyi Zhu, Luis J. Sigal, Renhuan Xu, Huabin Zhu

Department of Microbiology and Immunology Faculty Papers

Because of the rapid mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an effective vaccine against SARS-CoV-2 variants is needed to prevent coronavirus disease 2019 (COVID-19). T cells, in addition to neutralizing antibodies, are an important component of naturally acquired protective immunity, and a number of studies have shown that T cells induced by natural infection or vaccination contribute significantly to protection against several viral infections including SARS-CoV-2. However, it has never been tested whether a T cell-inducing vaccine can provide significant protection against SARS-CoV-2 infection in the absence of preexisting antibodies. In this study, we designed and evaluated …

Identification Of Collaborative Cross Mouse Strains Permissive To Salmonella Enterica Serovar Typhi Infection, Kishore Alugupalli, Sudeep Kothari, Matthew P Cravens, Justin A Walker, Darren T Dougharty, Gregory S. Dickinson, Louis A Gatto, Andreas J Bäumler, Tamding Wangdi, Darla R Miller, Fernando Pardo-Manuel De Villena, Linda D Siracusa

Department of Microbiology and Immunology Faculty Papers

Salmonella enterica serovar Typhi is the causative agent of typhoid fever restricted to humans and does not replicate in commonly used inbred mice. Genetic variation in humans is far greater and more complex than that in a single inbred strain of mice. The Collaborative Cross (CC) is a large panel of recombinant inbred strains which has a wider range of genetic diversity than laboratory inbred mouse strains. We found that the CC003/Unc and CC053/Unc strains are permissive to intraperitoneal but not oral route of S. Typhi infection and show histopathological changes characteristic of human typhoid. These CC strains are immunocompetent, …

The Lack Of Natural Igm Increases Susceptibility And Impairs Anti-Vi Polysaccharide Igg Responses In A Mouse Model Of Typhoid, Akhil S. Alugupalli, Matthew P. Cravens, Justin A. Walker, Dania Gulandijany, Gregory S. Dickinson, Genevieve Lewis, Gudrun F. Debes, Dieter M. Schifferli, Andreas J. Bäumler, Kishore R. Alugupalli

Department of Microbiology and Immunology Faculty Papers

Circulating IgM present in the body prior to any apparent Ag exposure is referred to as natural IgM. Natural IgM provides protective immunity against a variety of pathogens. Salmonella enterica serovar Typhi (S. Typhi) is the causative agent of typhoid fever in humans. Because mice are not permissive to S. Typhi infection, we employed a murine model of typhoid using S. enterica serovar Typhimurium expressing the Vi polysaccharide (ViPS) of S. Typhi (S. Typhimurium strain RC60) to evaluate the role of natural IgM in pathogenesis. We found that natural mouse IgM binds to S. Typhi and S. Typhimurium. The severity …

Interferon Partly Dictates A Divergent Transcriptional Response In Poxvirus-Infected And Bystander Inflammatory Monocytes, Carolina R Melo-Silva, Marisa I Roman, Cory J Knudson, Lingjuan Tang, Ren-Huan Xu, Michel Tassetto, Patrick Dolan, Raul Andino, Luis J. Sigal

Department of Microbiology and Immunology Faculty Papers

Inflammatory monocytes (iMOs) and B cells are the main targets of the poxvirus ectromelia virus (ECTV) in the lymph nodes of mice and play distinct roles in surviving the infection. Infected and bystander iMOs control ECTV's systemic spread, preventing early death, while B cells make antibodies that eliminate ECTV. Our work demonstrates that within an infected animal that survives ECTV infection, intrinsic and bystander infection of iMOs and B cells differentially control the transcription of genes important for immune cell function and, perhaps, cell identity. Bystander cells upregulate metabolism, antigen presentation, and interferon-stimulated genes. Infected cells downregulate many cell-type-specific genes …

Human Dectin-1 Deficiency Impairs Macrophage-Mediated Defense Against Phaeohyphomycosis, Rebecca A. Drummond, Jigar V. Desai, Amy P. Hsu, Vasileios Oikonomou, Donald C. Vinh, Joshua A. Acklin, Michael S. Abers, Magdalena A. Walkiewicz, Sarah L. Anzick, Muthulekha Swamydas, Simon Vautier, Mukil Natarajan, Andrew J. Oler, Daisuke Yamanaka, Katrin D. Mayer-Barber, Yoichiro Iwakura, David Bianchi, Brian Driscoll, Ken Hauck, Ahnika Kline, Nicholas S.P. Viall, Christa S. Zerbe, Elise M.N. Ferré, Monica M. Schmitt, Tom Dimaggio, Stefania Pittaluga, John A. Butman, Adrian M. Zelazny, Yvonne R. Shea, Cesar A. Arias, Cameron Ashbaugh, Maryam Mahmood, Zelalem Temesgen, Alexander G. Theofiles, Masayuki Nigo, Varsha Moudgal, Karen C. Bloch, Sean G. Kelly, M. Suzanne Whitworth, Ganesh Rao, Cindy J. Whitener, Neema Mafi, Juan Gea-Banacloche, Lawrence C. Kenyon, William R. Miller, Katia Boggian, Andrea Gilbert, Matthew Sincock, Alexandra F. Freeman, John E. Bennett, Rodrigo Hasbun, Constantinos M. Mikelis, Kyung J. Kwon-Chung, Yasmine Belkaid, Gordon D. Brown, Jean K. Lim, Douglas B. Kuhns, Steven M. Holland, Michail S. Lionakis

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Subcutaneous phaeohyphomycosis typically affects immunocompetent individuals following traumatic inoculation. Severe or disseminated infection can occur in CARD9 deficiency or after transplantation, but the mechanisms protecting against phaeohyphomycosis remain unclear. We evaluated a patient with progressive, refractory Corynespora cassiicola phaeohyphomycosis and found that he carried biallelic deleterious mutations in CLEC7A encoding the CARD9-coupled, β-glucan-binding receptor, Dectin-1. The patient's PBMCs failed to produce TNF-α and IL-1β in response to β-glucan and/or C. cassiicola. To confirm the cellular and molecular requirements for immunity against C. cassiicola, we developed a mouse model of this infection. Mouse macrophages required Dectin-1 and CARD9 for IL-1β and …

Caspase-8 Inactivation Drives Autophagy-Dependent Inflammasome Activation In Myeloid Cells., Yung-Hsuan Wu, Shu-Ting Mo, I-Ting Chen, Fu-Yi Hsieh, Shie-Liang Hsieh, Jianke Zhang, Ming-Zong Lai

Department of Microbiology and Immunology Faculty Papers

Caspase-8 activity controls the switch from cell death to pyroptosis when apoptosis and necroptosis are blocked, yet how caspase-8 inactivation induces inflammasome assembly remains unclear. We show that caspase-8 inhibition via IETD treatment in Toll-like receptor (TLR)-primed Fadd-/-Ripk3-/- myeloid cells promoted interleukin-1β (IL-1β) and IL-18 production through inflammasome activation. Caspase-8, caspase-1/11, and functional GSDMD, but not NLRP3 or RIPK1 activity, proved essential for IETD-triggered inflammasome activation. Autophagy became prominent in IETD-treated Fadd-/-Ripk3-/- macrophages, and inhibiting it attenuated IETD-induced cell death and IL-1β/IL-18 production. In contrast, inhibiting GSDMD or autophagy did not prevent IETD-induced septic …

Attenuation Of Relapsing Fever Neuroborreliosis In Mice By Il-17a Blockade, Meihui Cheng, Jingwen Xu, Kaiyun Ding, Jing Zhang, Wei Lu, Jiansheng Liu, Jiahong Gao, Kishore R Alugupalli, Hongqi Liu

Department of Microbiology and Immunology Faculty Papers

Relapsing fever due to Borrelia hermsiiis characterized by recurrent bacteremia episodes. However, infection of B. hermsii, if not treated early, can spread to various organs including the central nervous system (CNS). CNS disease manifestations are commonly referred to as relapsing fever neuroborreliosis (RFNB). In the mouse model of B. hermsiiinfection, we have previously shown that the development of RFNB requires innate immune cells as well as T cells. Here, we found that prior to the onset of RFNB, an increase in the systemic proinflammatory cytokine response followed by sustained levels of IP-10 concurrent with the CNS disease phase. RNA sequencing …

Pre-Exposure To Mrna-Lnp Inhibits Adaptive Immune Responses And Alters Innate Immune Fitness In An Inheritable Fashion, Zhen Qin, Aurélie Bouteau, Christopher Herbst, Botond Z. Igyártó

Department of Microbiology and Immunology Faculty Papers

Hundreds of millions of SARS-CoV-2 mRNA-LNP vaccine doses have already been administered to humans. However, we lack a comprehensive understanding of the immune effects of this platform. The mRNA-LNP-based SARS-CoV-2 vaccine is highly inflammatory, and its synthetic ionizable lipid component responsible for the induction of inflammation has a long in vivo half-life. Since chronic inflammation can lead to immune exhaustion and non-responsiveness, we sought to determine the effects of pre-exposure to the mRNA-LNP on adaptive immune responses and innate immune fitness. We found that pre-exposure to mRNA-LNPs or LNP alone led to long-term inhibition of the adaptive immune response, which …

Is Strongyloides Stercoralis Hyperinfection Induced By Gglucocorticoids A Result Of Both Suppressed Host Immunity And Altered Parasite Genetics?, De'broski R Herbert, Jonathan D C Stoltzfus, Heather L Rossi, David Abraham

Department of Microbiology and Immunology Faculty Papers

The gastrointestinal (GI) nematode Strongyloides stercoralis (S.s.) causes human strongyloidiasis, a potentially life-threatening disease that currently affects over 600 million people globally. The uniquely pernicious aspect of S.s. infection, as compared to all other GI nematodes, is its autoinfective larval stage (L3a) that maintains a low-grade chronic infection, allowing undetectable persistence for decades. Infected individuals who are administered glucocorticoid therapy can develop a rapid and often lethal hyperinfection syndrome within days. Hyperinfection patients often present with dramatic increases in first- and second-stage larvae and L3a in their GI tract, with L3a widely disseminating throughout host organs leading to sepsis. How …

Similarly Efficacious Anti-Malarial Drugs Sj733 And Pyronaridine Differ In Their Ability To Remove Circulating Parasites In Mice, Arya Sheelanair, Aleksandra S. Romanczuk, Rosemary A. Aogo, Rohit Nemai Haldar, Lianne I. M. Lansink, Deborah Cromer, Yandira G. Salinas, R. Kiplin Guy, James S. Mccarthy, Miles P. Davenport, Ashraful Haque, David S. Khoury

Pharmaceutical Sciences Faculty Publications

BACKGROUND: Artemisinin-based combination therapy (ACT) has been a mainstay for malaria prevention and treatment. However, emergence of drug resistance has incentivised development of new drugs. Defining the kinetics with which circulating parasitized red blood cells (pRBC) are lost after drug treatment, referred to as the "parasite clearance curve", has been critical for assessing drug efficacy; yet underlying mechanisms remain partly unresolved. The clearance curve may be shaped both by the rate at which drugs kill parasites, and the rate at which drug-affected parasites are removed from circulation.

METHODS: In this context, two anti-malarials, SJ733, and an ACT partner drug, pyronaridine …

Langerhans Cells And Cdc1s Play Redundant Roles In Mrna-Lnp Induced Protective Anti-Influenza And Anti-Sars-Cov-2 Immune Responses, Sonia Ndeupen, Aurélie Bouteau, Christopher Herbst, Zhen Qin, Sonya Jacobsen, Nicholas E Powers, Zachary Hutchins, Drishya Kurup, Leila Zabihi Diba, Megan Watson, Holly Ramage, Botond Z. Igyártó

Department of Microbiology and Immunology Faculty Papers

Nucleoside modified mRNA combined with Acuitas Therapeutics' lipid nanoparticles (LNPs) has been shown to support robust humoral immune responses in many preclinical animal vaccine studies and later in humans with the SARS-CoV-2 vaccination. We recently showed that this platform is highly inflammatory due to the LNPs' ionizable lipid component. The inflammatory property is key to support the development of potent humoral immune responses. However, the mechanism by which this platform drives T follicular helper (Tfh) cells and humoral immune responses remains unknown. Here we show that lack of Langerhans cells or cDC1s neither significantly affected the induction of PR8 HA …

Bias Of The Immune Response To Pneumocystis Murina Does Not Alter The Ability Of Neonatal Mice To Clear The Infection, Cathryn J. Kurkjian, Melissa L. Hollifield, David J. Feola, Beth A. Garvy

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Newborn mice are unable to clear Pneumocystis (PC) infection with the same efficiency as adults due, in part, to their inability to develop a robust immune response to infection until three weeks of age. It is known that infants tend develop a Th2 skewed response to antigen so we sought to determine whether a biased cytokine response altered the clearance of PC infection in neonatal mice. P. murina infection in neonatal mice resulted in increased IL-4 expression by CD4 T cells and myeloid cells, augmented IL-13 secretion within the airways and increased arginase activity in the airways, indicative of Th2-type …

Candida Cell-Surface-Specific Monoclonal Antibodies Protect Mice Against Candida Auris Invasive Infection, Jonothan Rosario-Colon, Karen Eberle, Abby Adams, Evan Courville, Hong Xin

School of Graduate Studies Faculty Publications

Candida auris is a multidrug-resistant fungal pathogen that can cause disseminated bloodstream infections with up to 60% mortality in susceptible populations. Of the three major classes of antifungal drugs, most C. auris isolates show high resistance to azoles and polyenes, with some clinical isolates showing resistance to all three drug classes. We reported in this study a novel approach to treating C. auris disseminated infections through passive transfer of monoclonal antibodies (mAbs) targeting cell surface antigens with high homology in medically important Candida species. Using an established A/J mouse model of disseminated infection that mimics human candidiasis, we showed that …

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

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

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

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 BRAF^V600E 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 BRAF^V600E/ERK signaling and Abl kinases. We demonstrate that BRAF^V600E/ERK play a critical role in binding, phosphorylating and regulating Abl localization and Abl/Arg activation …

April:Taci Axis Is Dispensable For The Immune Response To Rabies Vaccination., Shannon L. Haley, Evgeni P. Tzvetkov, Andrew G. Lytle, Kishore R. Alugupalli, Joseph R. Plummer, James P. Mcgettigan

Department of Microbiology and Immunology Faculty Papers

There is significant need to develop a single-dose rabies vaccine to replace the current multi-dose rabies vaccine regimen and eliminate the requirement for rabies immune globulin in post-exposure settings. To accomplish this goal, rabies virus (RABV)-based vaccines must rapidly activate B cells to secrete antibodies which neutralize pathogenic RABV before it enters the CNS. Increased understanding of how B cells effectively respond to RABV-based vaccines may improve efforts to simplify post-exposure prophylaxis (PEP) regimens. Several studies have successfully employed the TNF family cytokine a proliferation-inducing ligand (APRIL) as a vaccine adjuvant. APRIL binds to the receptors TACI and B cell …

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

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

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

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

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 …

Dendritic Cell Autophagy Contributes To Herpes Simplex Virus-Driven Stromal Keratitis And Immunopathology, Yike Jiang, Xiaotang Yin, Patrick M. Stuart, David A. Leib

Dartmouth Scholarship

Herpetic stromal keratitis (HSK) is a blinding ocular disease that is initiated by HSV-1 and characterized by chronic inflammation in the cornea. Although HSK immunopathology of the cornea is well documented in animal models, events preceding this abnormal inflammatory cascade are poorly understood. In this study, we have examined the activation of pathological CD4T cells in the development of HSK. Dendritic cell autophagy (DC-autophagy) is an important pathway regulating ma- jor histocompatibility complex class II (MHCII)-dependent antigen presentation and proper CD4T cell activation during infectious diseases. Using DC-autophagy-deficient mice, we found that DC-autophagy significantly and specifically contributes to HSK disease …

Parasite Manipulation Of The Invariant Chain And The Peptide Editor H2-Dm Affects Major Histocompatibility Complex Class Ii Antigen Presentation During Toxoplasma Gondii Infection, Louis-Philippe Leroux, Manami Nishi, Sandy El-Hage, Barbara A. Fox, David I Bzik, Florence Dzierszinsk

Dartmouth Scholarship

Toxoplasma gondii is an obligate intracellular protozoan parasite. This apicomplexan is the causative agent of toxoplasmosis, a leading cause of central nervous system disease in AIDS. It has long been known that T. gondii interferes with major histocompatibility complex class II (MHC-II) antigen presentation to attenuate CD4(+) T cell responses and establish persisting infections. Transcriptional downregulation of MHC-II genes by T. gondii was previously established, but the precise mechanisms inhibiting MHC-II function are currently unknown. Here, we show that, in addition to transcriptional regulation of MHC-II, the parasite modulates the expression of key components of the MHC-II antigen presentation pathway, …

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

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

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 (InlA^m-expressing) L. monocytogenes recovered from the mesenteric lymph nodes (MLN) was extracellular within the first few days after foodborne infection. In addition, …