Virology Commons^™

Exploring The Transformative Effects Of Calorie Restriction On The Lacrimal Gland In Adult Mice, Olivier Mauduit, Prashant Kumar, Kaitlin K Scholand, Emre Aksan, Laura Schaefer, Anmar Abu-Romman, Vanessa Delcroix, Zhiyuan Yu, Aude I Sindikubwabo, Ron Korstanje, Helen P Makarenkova, Cintia S De Paiva

Faculty, Staff and Students Publications

Advanced age is one of the most recognizable risk factors for dry eye. Dry eye disease affects millions worldwide and can result from age-related lacrimal gland dysfunction, which correlates with a decline in lacrimal gland secretory cell function and chronic inflammation. This study investigated the potential of calorie restriction to maintain lacrimal gland and ocular surface health. Adult female C57BL/6 J mice were subjected to a 40% calorie restriction for 4 months, starting at 6-7 months and continuing until 10-11 months. These mice were compared to controls fed ad libitum. Bulk RNA sequencing of lacrimal glands, conjunctiva, and cornea subjected …

Oral Dosing Of The Nucleoside Analog Obeldesivir Is Efficacious Against Rsv Infection In African Green Monkeys, Jared Pitts, J Lizbeth Reyes Zamora, Savrina Manhas, Thomas Aeschbacher, Josolyn Chan, Vincent Cutillas, Varsha Nair, Nicholas C Riola, Arya Vijjapurapu, Meghan S Vermillion, Stacey Eng, Christopher Richards, Dong Han, Jason K Perry, Subhra Chaudhuri, Szu-Wen Liu, Clarissa Martinez, Nadine Peinovich, Kai-Hui Sun, Arthur Cai, Ross Martin, Jasmine Moshiri, Charlotte Hedskog, Darius Babusis, Dustin S Siegel, Rao Kalla, Vasanthi Avadhanula, Pedro A Piedra, Kim Stobbelaar, Peter L Delputte, Caleb Marceau, Roberto Mateo, Evguenia Maiorova, Hongmei Mo, Raju Subramanian, Richard L Mackman, Tomas Cihlar, Simon P Fletcher, John P Bilello

Faculty, Staff and Students Publications

Respiratory syncytial virus (RSV) is a significant cause of morbidity and mortality in high-risk populations. Although prophylactic options are available, there are no effective oral therapeutics for RSV infection. Obeldesivir (ODV) is an orally bioavailable prodrug of the nucleoside analog GS-441524, which is converted intracellularly to its active nucleoside triphosphate and inhibits the RSV RNA polymerase. Here we report the potent antiviral activity of ODV against geographically and temporally diverse RSV A and B clinical isolates (EC50: 0.20–0.66 μM). Resistance selection studies with ODV and GS-441524 against RSV identify a single amino acid substitution, I777L, in the L polymerase with …

Microbial Biosensor For Sensing And Treatment Of Intestinal Inflammation, Duolong Zhu, Jeffrey Galley, Jason Pizzini, Elena Musteata, Martin V Douglas, Walter J Chazin, Eric P Skaar, Jeffrey J Tabor, Robert A Britton

Faculty, Staff and Students Publications

Synthetic biology has enabled the development of biosensors to detect intestinal inflammation, yet few target the clinically validated biomarker of intestinal inflammation calprotectin with both diagnostic and therapeutic capabilities. Here, an optimized calprotectin biosensor is presented that leverages a zinc uptake regulator (Zur) controlled promoter coupled with a memory circuit to detect and record intestinal inflammation in vivo. The level of biosensor activation strongly correlates with calprotectin levels in the colon of two independent mouse models of colitis. Coupling of the biosensor with the production of the anti-inflammatory cytokine IL10 allowed for the resolution of chemically induced colitis, demonstrating the …

Aged Regulatory T Cells Fail To Control Autoimmune Lacrimal Gland Pathogenic Cd4+ T Cells, Kaitlin K Scholand, Laura Schaefer, Gowthaman Govindarajan, Zhiyuan Yu, Jeremias G Galletti, Cintia S De Paiva

Faculty, Staff and Students Publications

CD25KO mice are a model of Sjögren disease. CD25KO mice have severe inflammation and infiltrating lymphocytes to the lacrimal glands (LG). Whether the pathogenicity of CD25KO CD4+ T cells can be controlled in vivo by Tregs is unknown. Eight-week-old B6 and CD25KO mice LGs were submitted for RNA bulk sequencing. A total of 3481 genes were differentially expressed in CD25KO LG compared to B6. Tear washing analysis identified CD25KO mice had elevated protein levels of TNF, IFN-γ, and CCL5 and decreased protein levels of IL-12p40 and VEGF-A. Co-adoptive transfer of CD25KO CD4+ T cells with either young or aged B6 …

Control Of Clostridioides Difficile Virulence And Physiology By The Flagellin Homeostasis Checkpoint Flic-Fliw-Csra In The Absence Of Motility, Duolong Zhu, Katherine J Wozniak, Firas Midani, Shaohui Wang, Xingmin Sun, Robert A Britton

Faculty, Staff and Students Publications

Mutations affecting Clostridioides difficile flagellin (FliC) have been shown to be hypervirulent in animal models and display increased toxin production and alterations in central metabolism. The regulation of flagellin levels in bacteria is governed by a tripartite regulatory network involving fliC, fliW, and csrA, which creates a feedback system to regulate flagella production. Through genomic analysis of C. difficile clade 5 strains (non-motile), we identified they have jettisoned many of the genes required for flagellum biosynthesis yet retain the major flagellin gene fliC and regulatory gene fliW. We therefore investigated the roles of fliC, fliW …

Viroporin Activity Is Necessary For Intercellular Calcium Signals That Contribute To Viral Pathogenesis, J Thomas Gebert, Francesca J Scribano, Kristen A Engevik, Ethan M Huleatt, Michael R Eledge, Lauren E Dorn, Asha A Philip, Takahiro Kawagishi, Harry B Greenberg, John T Patton, Joseph M Hyser

Faculty, Staff and Students Publications

Viruses engage in a variety of processes to subvert host defenses and create an environment amenable to replication. Here, using rotavirus as a prototype, we show that calcium conductance out of the endoplasmic reticulum by the virus encoded ion channel, NSP4, induces intercellular calcium waves that extend beyond the infected cell and contribute to pathogenesis. Viruses that lack the ability to induce this signaling show diminished viral shedding and attenuated disease in a mouse model of rotavirus diarrhea. This implicates nonstructural protein 4 (NSP4) as a virulence factor and provides mechanistic insight into its mode of action. Critically, this …

Tamm-Horsfall Protein Augments Neutrophil Netosis During Urinary Tract Infection, Vicki Mercado-Evans, Holly Branthoover, Claude Chew, Camille Serchejian, Alexander B Saltzman, Marlyd E Mejia, Jacob J Zulk, Ingrid Cornax, Victor Nizet, Kathryn A Patras

Faculty, Staff and Students Publications

Urinary neutrophils are a hallmark of urinary tract infection (UTI), yet the mechanisms governing their activation, function, and efficacy in controlling infection remain incompletely understood. Tamm-Horsfall glycoprotein (THP), the most abundant protein in urine, uses terminal sialic acids to bind an inhibitory receptor and dampen neutrophil inflammatory responses. We hypothesized that neutrophil modulation is an integral part of THP-mediated host protection. In a UTI model, THP-deficient mice showed elevated urinary tract bacterial burdens, increased neutrophil recruitment, and more severe tissue histopathological changes compared with WT mice. Furthermore, THP-deficient mice displayed impaired urinary NETosis during UTI. To investigate the effect of …

Progress Toward A Vaccine For Extraintestinal Pathogenic Coli (Expec) Ii: Efficacy Of A Toxin-Autotransporter Dual Antigen Approach, Yikun Xing, Justin R Clark, James D Chang, Jacob J Zulk, Dylan M Chirman, Felipe-Andres Piedra, Ellen E Vaughan, Haroldo J Hernandez Santos, Kathryn A Patras, Anthony W Maresso

Faculty, Staff and Students Publications

Extraintestinal pathogenic Escherichia coli (ExPEC) is a leading cause of worldwide morbidity and mortality, the top cause of antimicrobial-resistant (AMR) infections, and the most frequent cause of life-threatening sepsis and urinary tract infections (UTI) in adults. The development of an effective and universal vaccine is complicated by this pathogen’s pan-genome, its ability to mix and match virulence factors and AMR genes via horizontal gene transfer, an inability to decipher commensal from pathogens, and its intimate association and co-evolution with mammals. Using a pan virulome analysis of >20,000 sequenced E. coli strains, we identified the secreted cytolysin α-hemolysin (HlyA) as a …

Select Gut Microbiota Impede Rotavirus Vaccine Efficacy, Vu L Ngo, Yanling Wang, Yadong Wang, Zhenda Shi, Robert Britton, Jun Zou, Sasirekha Ramani, Baoming Jiang, Andrew T Gewirtz

Faculty, Staff and Students Publications

BACKGROUND & AIMS: The protection provided by rotavirus (RV) vaccines is highly heterogeneous among individuals. We hypothesized that microbiota composition might influence RV vaccine efficacy.

METHODS: First, we examined the potential of segmented filamentous bacteria (SFB) colonization to influence RV vaccine efficacy in mice. Next, we probed the influence of human microbiomes on RV vaccination via administering mice fecal microbial transplants (FMTs) from children with robust or minimal RV vaccine responsiveness. Post-FMT, mice were subjected to RV vaccination followed by RV challenge.

RESULTS: SFB colonization induced a phenotype that was reminiscent of RV vaccine failure (ie, failure to generate RV …

Age-Associated Temporal Decline In Butyrate-Producing Bacteria Plays A Key Pathogenic Role In The Onset And Progression Of Neuropathology And Memory Deficits In 3×Tg-Ad Mice, Paula M Chilton, Smita S Ghare, Benjamin T Charpentier, Scott A Myers, Aakarsha V Rao, Joseph F Petrosino, Kristi L Hoffman, John C Greenwell, Neetu Tyagi, Jyotirmaya Behera, Yali Wang, Lucy J Sloan, Jingwen Zhang, Christopher B Shields, Gregory E Cooper, Leila Gobejishvili, Scott R Whittemore, Craig J Mcclain, Shirish S Barve

Faculty, Staff and Students Publications

Alterations in the gut-microbiome-brain axis are increasingly being recognized to be involved in Alzheimer's disease (AD) pathogenesis. However, the functional consequences of enteric dysbiosis linking gut microbiota and brain pathology in AD progression remain largely undetermined. The present work investigated the causal role of age-associated temporal decline in butyrate-producing bacteria and butyrate in the etiopathogenesis of AD. Longitudinal metagenomics, neuropathological, and memory analyses were performed in the 3×Tg-AD mouse model. Metataxonomic analyses showed a significant temporal decline in the alpha diversity marked by a decrease in butyrate-producing bacterial communities and a concurrent reduction in cecal butyrate production. Inferred metagenomics analysis …

Vaginal Microbial Dynamics And Pathogen Colonization In A Humanized Microbiota Mouse Model, Marlyd E Mejia, Vicki Mercado-Evans, Jacob J Zulk, Samantha Ottinger, Korinna Ruiz, Mallory B Ballard, Stephanie W Fowler, Robert A Britton, Kathryn A Patras

Faculty, Staff and Students Publications

Vaginal microbial composition is associated with differential risk of urogenital infection. Although Lactobacillus spp. are thought to confer protection against infection, the lack of in vivo models resembling the human vaginal microbiota remains a prominent barrier to mechanistic discovery. Using 16S rRNA amplicon sequencing of C57BL/6J female mice, we found that vaginal microbial composition varies within and between colonies across three vivaria. Noting vaginal microbial plasticity in conventional mice, we assessed the vaginal microbiome of humanized microbiota mice (

Exercise Reprograms The Inflammatory Landscape Of Multiple Stem Cell Compartments During Mammalian Aging, Ling Liu, Soochi Kim, Matthew T Buckley, Jaime M Reyes, Jengmin Kang, Lei Tian, Mingqiang Wang, Alexander Lieu, Michelle Mao, Cristina Rodriguez-Mateo, Heather D Ishak, Mira Jeong, Joseph C Wu, Margaret A Goodell, Anne Brunet, Thomas A Rando

Faculty, Staff and Students Publications

Exercise has the ability to rejuvenate stem cells and improve tissue regeneration in aging animals. However, the cellular and molecular changes elicited by exercise have not been systematically studied across a broad range of cell types in stem cell compartments. We subjected young and old mice to aerobic exercise and generated a single-cell transcriptomic atlas of muscle, neural, and hematopoietic stem cells with their niche cells and progeny, complemented by whole transcriptome analysis of single myofibers. We found that exercise ameliorated the upregulation of a number of inflammatory pathways associated with old age and restored aspects of intercellular communication mediated …

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 …

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 …

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.

Cd40-Associated Traf 6 Signaling Is Required For Disease Induction In A Retrovirus-Induced Murine Immunodeficiency, Kathy A. Green, Cory L. Ahonen, W. James Cook, William R. Green

Dartmouth Scholarship

LP-BM5 retrovirus-infected C57BL/6 mice develop splenomegaly, lymphadenopathy, hypergammaglobulinemia, and immunodeficiency; thus, this disease has been named mouse AIDS. In this syndrome, CD154/CD40 interactions are required for but do not mediate disease by upregulation of CD80 or CD86. We report here that there is nonetheless a necessity for CD40 signaling competence, specifically an intact tumor necrosis factor receptor-associated factor 6 (TRAF 6) binding site.