Medical Microbiology Commons^™

Resistance To Ectromelia Virus Infection Requires Cgas In Bone Marrow-Derived Cells Which Can Be Bypassed With Cgamp Therapy., Eric B. Wong, Brian Montoya, Maria Ferez, Colby Stotesbury, Luis J. Sigal

Department of Microbiology and Immunology Faculty Papers

Cells sensing infection produce Type I interferons (IFN-I) to stimulate Interferon Stimulated Genes (ISGs) that confer resistance to viruses. During lympho-hematogenous spread of the mouse pathogen ectromelia virus (ECTV), the adaptor STING and the transcription factor IRF7 are required for IFN-I and ISG induction and resistance to ECTV. However, it is unknown which cells sense ECTV and which pathogen recognition receptor (PRR) upstream of STING is required for IFN-I and ISG induction. We found that cyclic-GMP-AMP (cGAMP) synthase (cGAS), a DNA-sensing PRR, is required in bone marrow-derived (BMD) but not in other cells for IFN-I and ISG induction and for …

Examining Multiple Cellular Pathways At Once Using Multiplex Hextuple Luciferase Assaying, Alejandro Sarrion-Perdigones, Lyra Chang, Yezabel Gonzalez, Tatiana Gallego-Flores, Damian W Young, Koen J T Venken

Faculty, Staff and Students Publications

Sensitive simultaneous assessment of multiple signaling pathways within the same cells requires orthogonal reporters that can assay over large dynamic ranges. Luciferases are such genetically encoded candidates due to their sensitivity, versatility, and cost-effectiveness. We expand luciferase multiplexing in post-lysis endpoint luciferase assays from two to six. Light emissions are distinguished by a combination of distinct substrates and emission spectra deconvolution. All six luciferase reporter units are stitched together into one plasmid facilitating delivery of all reporter units through a process we termed solotransfection, minimizing experimental errors. We engineer a multiplex hextuple luciferase assay to probe pathway fluxes through five …

Langerhans Cells Orchestrate The Protective Antiviral Innate Immune Response In The Lymph Node., Eric B. Wong, Brian Montoya, Colby Stotesbury, Maria Ferez, Ren-Huan Xu, Luis J. Sigal

Department of Microbiology and Immunology Faculty Papers

During disseminating viral infections, a swift innate immune response (IIR) in the draining lymph node (dLN) that restricts systemic viral spread is critical for optimal resistance to disease. However, it is unclear how this IIR is orchestrated. We show that after footpad infection of mice with ectromelia virus, dendritic cells (DCs) highly expressing major histocompatibility complex class II (MHC class II^hi DCs), including CD207⁺ epidermal Langerhans cells (LCs), CD103⁺CD207⁺ double-positive dermal DCs (DP-DCs), and CD103⁻CD207⁻ double-negative dermal DCs (DN-DCs) migrate to the dLN from the skin carrying virus. MHC class II^{hi …}

Nlrp6 In Gram-Positive Pneumonia And Sepsis, Laxman Ghimire

LSU Doctoral Dissertations

Acute lower respiratory infections (pneumonia) and pneumonia-derived sepsis are among the leading causes of death in the world causing 7.8 million deaths annually. In this regard, Methicillin-resistant Staphylococcus aureus (MRSA) is endemic in the US and implicated for causing high mortality-associated necrotizing pneumonia and aggravating viral pneumonia with superinfection. Additionally, sepsis is the 7^th leading cause of death among newborns in the US and is responsible for more than 750,000 hospitalization cases every year. Although there is a plethora of research in both pneumonia and sepsis, the detailed pathophysiology still remains elusive. Understanding the host defense mechanism will help …

Reverse Zoonosis Of Pandemic A(H1n1)Pdm09 Influenza Viruses At The Swine/Human Interface, Daniel Gene Darnell

Theses and Dissertations (ETD)

The 2009 pandemic influenza A(H1N1)pdm09 virus emerged from the swine population. Despite frequent zoonotic events, swine influenza viruses had not become established in humans previously and little is known about host-barriers which prevent swine influenza viruses from efficiently infecting humans. Thus, the emergence of the H1N1pdm09 viruses in humans and the subsequent reverse zoonoses back to swine offered an extremely valuable opportunity to expand current knowledge. We used our active swine farm surveillance platform in combination with viruses from the USDA surveillance program to look for evidence of interspecies transmission of H1N1pdm09 viruses in the US. We found phylogenetic evidence …

Inactivated Rabies Virus-Based Ebola Vaccine Preserved By Vaporization Is Heat-Stable And Immunogenic Against Ebola And Protects Against Rabies Challenge., Drishya Kurup, Christine R. Fisher, Todd G. Smith, Tiago Abreu-Mota, Yong Yang, Felix R. Jackson, Nadia Gallardo-Romero, Richard Franka, Victor Bronshtein, Matthias J. Schnell

Department of Microbiology and Immunology Faculty Papers

BACKGROUND: Ebola virus (EBOV) is a highly lethal member of the Filoviridae family associated with human hemorrhagic disease. Despite being a sporadic disease, it caused a large outbreak in 2014-2016 in West Africa and another outbreak recently in the Democratic Republic of Congo. Several vaccine candidates are currently in preclinical and clinical studies but none are stable without cold chain storage.

METHODS: We used preservation by vaporization (PBV), a novel processing technology to heat-stabilize FiloRab1 (inactivated rabies-based Ebola vaccine), a candidate Ebola vaccine, and stored the vials at temperatures ranging from 4°C to 50°C for 10 days to 12 months. …

Heme And Hemoglobin Utilization By Mycobacterium Tuberculosis., Avishek Mitra, Ying-Hui Ko, Gino Cingolani, Michael Niederweis

Department of Biochemistry and Molecular Biology Faculty Papers

Iron is essential for growth of Mycobacterium tuberculosis (Mtb), but most iron in the human body is stored in heme within hemoglobin. Here, we demonstrate that the substrate-binding protein DppA of the inner membrane Dpp transporter is required for heme and hemoglobin utilization by Mtb. The 1.27 Å crystal structure of DppA shows a tetrapeptide bound in the protein core and a large solvent-exposed crevice for heme binding. Mutation of arginine 179 in this cleft eliminates heme binding to DppA and prevents heme utilization by Mtb. The outer membrane proteins PPE36 and PPE62 are also required for heme and hemoglobin …

Dmbt1 Inhibition Of Pseudomonas Aeruginosa Twitching Motility Involves Its N-Glycosylation And Cannot Be Conferred By The Scavenger Receptor Cysteine-Rich Bacteria-Binding Peptide Domain., Jianfang Li, Stephanie J Wan, Matteo M E Metruccio, Sophia Ma, Kamran Nazmi, Floris J Bikker, David J. Evans, Suzanne M J Fleiszig

Faculty Publications & Research of the TUC College of Pharmacy

The scavenging capacity of glycoprotein DMBT1 helps defend mucosal epithelia against microbes. DMBT1 binding to multiple bacterial species involves its conserved Scavenger Receptor Cysteine-Rich (SRCR) domains, localized to a 16-mer consensus sequence peptide, SRCRP2. Previously, we showed that DMBT1 bound Pseudomonas aeruginosa pili, and inhibited twitching motility, a pilus-mediated movement important for virulence. Here, we determined molecular characteristics required for twitching motility inhibition. Heat-denatured DMBT1 lost capacity to inhibit twitching motility and showed reduced pili binding (~40%). Size-exclusion chromatography of Lys-C-digested native DMBT1 showed that only high-Mw fractions retained activity, suggesting involvement of the N-terminal containing repeated SRCR domains with …

Antibody Responses Against The Vaccine Antigens Ov-103 And Ov-Ral-2 Are Associated With Protective Immunity To Onchocerca Volvulus Infection In Both Mice And Humans., Parakkal Jovvian George, Jessica A. Hess, Sonia Jain, John B. Patton, Tingting Zhan, Nancy Tricoche, Bin Zhan, Maria Elena Bottazzi, Peter J. Hotez, David Abraham, Sara Lustigman

Department of Microbiology and Immunology Faculty Papers

BACKGROUND: The current strategy for the elimination of onchocerciasis is based on annual or bi-annual mass drug administration with ivermectin. However, due to several limiting factors there is a growing concern that elimination of onchocerciasis cannot be achieved solely through the current strategy. Additional tools are critically needed including a prophylactic vaccine. Presently Ov-103 and Ov-RAL-2 are the most promising vaccine candidates against an Onchocerca volvulus infection.

METHODOLOGY/PRINCIPAL FINDINGS: Protection induced by immunization of mice with the alum-adjuvanted Ov-103 or Ov-RAL-2 vaccines appeared to be antibody dependent since AID-/- mice that could not mount antigen-specific IgG antibody responses were not …

Role Of Dietary Flavonoid Compounds In Driving Patterns Of Microbial Community Assembly, Kerry L. Ivey, Andrew T. Chan, Jacques Izard, Aedin Cassidy, Geraint B. Rogers, Eric B. Rimm

Department of Food Science and Technology: Faculty Publications

Flavonoids are a group of polyphenolic dietary compounds found in many different plant-based foods. There is increasing evidence that higher flavonoid intake may be causally linked to a reduced risk of cardiovascular disease and other chronic diseases. The bioactivity and bioavailability of many dietary flavonoids can be influenced by gastrointestinal microbiome metabolism. However, the role that habitual flavonoid intake plays in shaping the human gut microbiome is poorly understood. We describe an application of an ecosystem-based analytic approach to nutritional, microbiome, and questionnaire data from a cohort of more than 240 generally healthy adult males to assess the role of …

Cytoplasmic Daxx Drives Sqstm1/P62 Phase Condensation To Activate Nrf2-Mediated Stress Response., Yi Yang, Thea L. Willis, Robert W. Button, Conor J. Strang, Yuhua Fu, Xue Wen, Portia R.C. Grayson, Tracey Evans, Rebecca J. Sipthorpe, Sheridan L. Roberts, Bing Hu, Jianke Zhang, Boxun Lu, Shouqing Luo

Department of Microbiology and Immunology Faculty Papers

Autophagy cargo recognition and clearance are essential for intracellular protein quality control. SQSTM1/p62 sequesters intracellular aberrant proteins and mediates cargo delivery for their selective autophagic degradation. The formation of p62 non-membrane-bound liquid compartments is critical for its function as a cargo receptor. The regulation of p62 phase separation/condensation has yet been poorly characterised. Using an unbiased yeast two-hybrid screening and complementary approaches, we found that DAXX physically interacts with p62. Cytoplasmic DAXX promotes p62 puncta formation. We further elucidate that DAXX drives p62 liquid phase condensation by inducing p62 oligomerisation. This effect promotes p62 recruitment of Keap1 and subsequent Nrf2-mediated …

Non-Thermal Plasma-Induced Immunogenic Cell Death In Cancer: A Topical Review., Marian Khalili, Lynsey Daniels, Abraham Lin, Fred C. Krebs, Adam E. Snook, Sander Bekeschus, Wilbur B. Bowne, Vandana Miller

Department of Pharmacology and Experimental Therapeutics Faculty Papers

Recent advances in biomedical research in cancer immunotherapy have identified the use of an oxidative stress-based approach to treat cancers, which works by inducing immunogenic cell death (ICD) in cancer cells. Since the anti-cancer effects of non-thermal plasma (NTP) are largely attributed to the reactive oxygen and nitrogen species that are delivered to and generated inside the target cancer cells, it is reasonable to postulate that NTP would be an effective modality for ICD induction. NTP treatment of tumors has been shown to destroy cancer cells rapidly and, under specific treatment regimens, this leads to systemic tumor-specific immunity. The translational …

An In Vitro Enrichment Strategy For Formulating Synergistic Synbiotics, Car Reen Kok, David Fabian Gomez Quintero, Clement Niyirora, Devin Rose, Amanda Li, Robert Hutkins

Food for Health: Publications

ABSTRACT Research on the role of diet on gut and systemic health has led to considerable interest toward identifying novel therapeutic modulators of the gut microbiome, including the use of prebiotics and probiotics. However, various host responses have often been reported among many clinical trials. This is in part due to competitive exclusion as a result of the absence of ecological niches as well as host mediated constraints via colonization resistance. In this research, we developed a novel in vitro enrichment (IVE) method for isolating autochthonous strains that can function as synergistic synbiotics and overcome these constraints. The method relied …

Elucidating Immune Signaling Of Influenza A Virus And Aspergillus Fumigatus Co-Infections Through Pioneered Model Development, Meagan Danyelle Rippee-Brooks

Graduate Theses/Dissertations

Bacterial co-infections with influenza A virus (IAV) are extremely serious and life-threatening. However, there exists limited understanding about the importance of fungal infections with IAV. Clinical case reports indicate that fungal co-infections do occur and suggest the IAV pandemic of 2009 had a propensity to predispose patients to secondary fungal infections more than previous IAV strains. IAV-fungal co-infections are marked by high mortality rates of 47 to 61% in previously healthy individuals between the ages of 20 and 60. Yet, the variables involved in this co-infection remain undetermined. I achieved effective recapitulation of this co-infection using a C57Bl/6 murine (mouse) …

From Vaccine Vector To Oncomodulation: Understanding The Complex Interplay Between Cmv And Cancer., Nicole A. Wilski, Christopher M. Snyder

Department of Microbiology and Immunology Faculty Papers

Cytomegalovirus (CMV) is a herpesvirus that establishes a persistent, but generally asymptomatic, infection in most people in the world. However, CMV drives and sustains extremely large numbers of antigen-specific T cells and is, therefore, emerging as an exciting platform for vaccines against infectious diseases and cancer. Indeed, pre-clinical data strongly suggest that CMV-based vaccines can sustain protective CD8+ T cell and antibody responses. In the context of vaccines for infectious diseases, substantial pre-clinical studies have elucidated the effcacy and protective mechanisms of CMV-based vaccines, including in non-human primate models of various infections. In the context of cancer vaccines, however, much …

Infection Potential Of Rickettsia Felis Via Ingestion, Matthew M. Schexnayder

LSU Master's Theses

Rickettsia felis is the etiologic agent of flea-borne spotted fever (FBSF) in humans and a poorly described cause of fever in animals. It is transmitted by its primary arthropod vector and reservoir host, the cat flea Ctenocephalides felis. Known routes of Rickettsia felis transmission between Rickettsia felis-infected cat fleas and vertebrate hosts include cutaneous bites and contamination of cutaneous wounds with infective flea feces. The bulk of FBSF infections occur in young children in Africa, though infections of people at all ages all over the world have been confirmed. As mammals and young children frequently come into contact …

Monocyte Anti-Inflammatory Activity Is Dictated By Metabolic Status During Staphylococcus Aureus Biofilm Infection, Kelsey J. Yamada

Theses & Dissertations

Staphylococcus aureus biofilms represent a significant cause of morbidity and economic burden and are often associated with nosocomial infections, including medically implanted devices. In particular, prosthetic joint infections (PJIs) are a growing concern due to the continued increase in orthopedic procedures. Staphylococcal species cause >50% of all PJIs, while S. aureus represents the most invasive and associated with the most morbidity. S. aureus-associated biofilm infections are recalcitrant to antibiotic therapy, due to both the acquisition of genetic elements and metabolic dormancy. Furthermore, S. aureus biofilm infections remain chronic because they cannot be cleared by the immune system. Recent studies …

Identification Of Anaerobes In Clinical Specimens Comparison Between The Rapid Ana Ii System And The Bruker Maldi-Tof Ms System Utilized In The Clinical Laboratory, Raymond Chow

Natural Sciences and Mathematics | Clinical Laboratory Sciences

Matrix-Assisted Laser Desorption and Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) has been revealed as an invaluable platform for identifying anaerobic bacteria in the clinical laboratory over traditional methods such as the RapID ANA II System.

A qualitative comparison is made, through the analysis of methodologies and specifications, to determine whether the RapID ANA II system or Bruker MALDI-TOF MS is more suitable for identifying anaerobic organism in the clinical laboratory. Based on the data reviewed, the MALDI-TOF MS is a more intuitive platform within the clinical laboratory due to its increased specificity, cost-effectiveness, and shorten turnaround time for the identification …

Development Of Methods To Evaluate The Use Of Medi-551 To Target Cd19 Transmembrane Proteins On B-Cells To Improve Systemic Sclerosis, Natalia Dohman

Honors Thesis

Systemic sclerosis, a subcategory of scleroderma, is a rare autoimmune disease that affects the skin and, in some cases, the internal organs of those diagnosed with the disease. There is currently no cure for this disease, only treatments to slow its progression. It is important to note that each individual diagnosed with scleroderma experience differences in severity and symptoms of the disease and are treated based on their symptoms, not as a whole. Many factors of this disease still remain unknown, such as what causes the disease or stimulates the onset of it. Recent studies have helped determine different treatment …

Role Of Atm In T Cell Dysfunction During Chronic Viral Infections, Juan Zhao

Electronic Theses and Dissertations

Hepatitis C virus (HCV) or human immunodeficiency virus (HIV) infection leads to a phenomenon of inflammaging, in which chronic infection or inflammation induces an immune aged phenotype with T cell dysfunction. Thus, HCV or HIV infection has been deemed as a model to study the mechanisms of T cell infammaging and viral persistence in humans. In this dissertation, T cell homeostasis, DNA damage and repair machineries were investigated in patients with chronic HCV or HIV infection at risk for inflammaging. We found a significant depletion in CD4 T cells, which was correlated with their apoptosis in chronically HCV/HIVinfected patients, compared …

Effects Of Ambient And Laser Light On Water Evaporation From The Surface Of Polyurethane Swabs Doped With Surfactant, Collin Campbell

Chemical Engineering Undergraduate Honors Theses

Polyurethane swabs are a common instrument for environmental sampling in the food, medical, and forensic fields due to their high recovery of organisms like viruses, spores, and bacteria. For sampling microbes in food and medical facilities, storage of the collected samples occurs under the absence of light to promote growth for more accurate testing. In the forensic fields, microbial growth results in sample contamination so the inhibition of this growth requires the drying of the swabs. This work studies the evaporation rates of water from polyurethane swabs under zero watt incident light, 30 W fluorescent bulb, 50 mW 532 nm …

Transcriptional Regulation Of Nlrc4 Inflammasome By Irf8, Ein Lee

Theses and Dissertations (ETD)

The NLRC4 inflammasome is a crucial part of the innate immune response against bacterial infections. We found that NLRC4 inflammasome activation in bone marrow-derived macrophages (BMDMs) is greatly dependent on interferon regulatory factor 8 (IRF8). NLRC4-mediated caspase-1 activation and subsequent production of the inflammasome-dependent cytokines IL-1β and IL-18 and cell death were impaired in IRF8-deficient cells. IRF8 mediated the transcription of genes encoding NAIPs, the receptors for NLRC4 inflammasome, which recognize bacterial flagellin and type III secretion system (T3SS) proteins. IRF8 was critical for host survival following infection with Salmonella Typhimurium or Burkholderia thailandensis. Furthermore, mice deficient in IRF8 were …

Rabies-Based Vaccine Induces Potent Immune Responses Against Nipah Virus., Rohan Keshwara, Thomas Shiels, Elena Postnikova, Drishya Kurup, Christoph Wirblich, Reed F. Johnson, Matthias J. Schnell

Department of Microbiology and Immunology Faculty Papers

Nipah Virus (NiV) is a re-emerging zoonotic pathogen in the genus Henipavirus of the Paramyxoviridae family of viruses. NiV is endemic to Bangladesh and Malaysia and is highly fatal to both livestock and humans (human case fatality rate = 74.5%). Currently, there is no approved vaccine against NiV on the market. The goal of this study was to use a recombinant RABV vector expressing NiV glycoprotein (NiV G) to develop a bivalent candidate vaccine against NiV disease and rabies virus (RABV) disease, which is also a significant health burden in the regions where NiV is endemic. The rabies vector is …

Role Of Ribosome Recycling Factor As A Ribosome Releasing Factor, Yoshio Inokuchi, Fabio Quaglia, Akikazu Hirashima, Yoshihiro Yamamoto, Hideko Kaji, A. Kaji

Department of Biochemistry and Molecular Biology Posters

The objective of this presentation is to study the in vivo actions of ribosome recycling factor (RRF) and compare them with those found in vitro. RRF is known to catalyze three separate reactions: release of tRNA and mRNA from the post-termination complex (PoTC), and splitting of the ribosome of the PoTC. To study the mechanism of RRF reaction in vivo, we used E. coli harboring temperature sensitive (ts) RRF and assayed by following downstream reading of translationally coupled ORF. At the non-permissive temperature, ribosomes remain on the termination codon of the junction sequence of coupled ORFs and translate downstream ORF …

Induction Of Lipid Bodies In Leishmania Infantum-Infected C57bl/6 Macrophages Of Male Versus Female Origin, Victor A. Soupene, Ryan D. Lockard, Mary E. Wilson, Nilda E. Rodriguez

Research in the Capitol

Worldwide, 12 million people are infected with Leishmania spp. parasites. Leishmania are transmitted by the bite of sand flies. The parasite is internalized by immune cells where they develop, reproduce, and spread to new immune cells causing disease. Epidemiological studies have shown that males are more likely to develop disease. We recently demonstrated that Leishmania infantum survive better in immune cells of male origin than in cells derived from females. We also showed that L. infantum infection is characterized by fat accumulation. Additional experiments have shown that infected immune cells from males accumulate more fat than cells from females. We …

Long-Term Use Of Antibiotics And Risk Of Colorectal Adenoma, Yin Cao, Kana Wu, Raaj Mehta, David A. Drew, Mingyang Song, Paul Lochhead, Long H. Nguyen, Jacques Izard, Charles S. Fuchs, Wendy S. Garrett, Curtis Huttenhower, Shuji Ogino, Edward L. Giovannucci, Andrew T. Chan

Department of Food Science and Technology: Faculty Publications

Objective: Recent evidence suggests that antibiotic use, which alters the gut microbiome, is associated with an increased risk of colorectal cancer. However, the association between antibiotic use and risk of colorectal adenoma, the precursor for the majority of colorectal cancers, has not been investigated.

Design: We prospectively evaluated the association between antibiotic use at age 20–39 and 40–59 (assessed in 2004) and recent antibiotic use (assessed in 2008) with risk of subsequent colorectal adenoma among 16,642 women aged ≥ 60 enrolled in the Nurses’ Health Study who underwent at least one colonoscopy through 2010. We used multivariate logistic …

Dynamic Molecular Changes During The First Week Of Human Life Follow A Robust Developmental Trajectory., Amy H. Lee, Casey P. Shannon, Nelly Amenyogbe, Tue B. Bennike, Joann Diray-Arce, Olubukola T. Idoko, Erin E. Gill, Rym Ben-Othman, William S. Pomat, Simon D. Van Haren, Kim-Anh Lê Cao, Momoudou Cox, Alansana Darboe, Reza Falsafi, Davide Ferrari, Daniel J. Harbeson, Daniel He, Cai Bing, Samuel J. Hinshaw, Jorjoh Ndure, Jainaba Njie-Jobe, Matthew A. Pettengill, Peter C. Richmond, Rebecca Ford, Gerard Saleu, Geraldine Masiria, John Paul Matlam, Wendy Kirarock, Elishia Roberts, Mehrnoush Malek, Guzmán Sanchez-Schmitz, Amrit Singh, Asimenia Angelidou, Kinga K. Smolen, Diana Vo, Ken Kraft, Kerry Mcenaney, Sofia Vignolo, Arnaud Marchant, Ryan R. Brinkman, Al Ozonoff, Robert E.W. Hancock, Anita H.J. Van Den Biggelaar, Hanno Steen, Scott J. Tebbutt, Beate Kampmann, Ofer Levy, Tobias R. Kollmann

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Systems biology can unravel complex biology but has not been extensively applied to human newborns, a group highly vulnerable to a wide range of diseases. We optimized methods to extract transcriptomic, proteomic, metabolomic, cytokine/chemokine, and single cell immune phenotyping data fromblood, a volume readily obtained from newborns. Indexing to baseline and applying innovative integrative computational methods reveals dramatic changes along a remarkably stable developmental trajectory over the first week of life. This is most evident in changes of interferon and complement pathways, as well as neutrophil-associated signaling. Validated across two independent cohorts of newborns from West Africa and Australasia, a …

Ripk1 Can Mediate Apoptosis In Addition To Necroptosis During Embryonic Development., Xuhua Zhang, John P. Dowling, Jianke Zhang

Department of Microbiology and Immunology Faculty Papers

RIPK1 has emerged as a key effector in programmed necrosis or necroptosis. This function of RIPK1 is mediated by its protein serine/threonine kinase activity and through the downstream kinase RIPK3. Deletion of RIPK1 prevents embryonic lethality in mice lacking FADD, a signaling adaptor protein required for activation of Caspase 8 in extrinsic apoptotic pathways. This indicates that FADD-mediated apoptosis inhibits RIPK1-dependent necroptosis to ensure successful embryogenesis. However, the molecular mechanism for this critical regulation remains unclear. In the current study, a novel mouse model has been generated, by disrupting a potential caspase cleavage site at aspartic residue (D)324 in RIPK1. …

Wave 2 Strains Of Atypical Vibrio Cholerae El Tor Caused The 2009-2011 Cholera Outbreak In Papua New Guinea, Andrew R. Greenhill, Ankur Mutreja, Dieter Bulach, Matthew J. Belousoff, Marinjho H. Jonduo, Deirdre A. Collins, Monalisa P. Kas, Johanna Wapling, Torsten Seemann, Alice Lafana, Gordon Dougan, Mark V. Brown, Paul F. Horwood

Research outputs 2014 to 2021

Vibrio cholerae is the causative agent of cholera, a globally important human disease for at least 200 years. In 2009-2011, the first recorded cholera outbreak in Papua New Guinea (PNG) occurred. We conducted genetic and phenotypic characterization of 21 isolates of V. cholerae, with whole-genome sequencing conducted on 2 representative isolates. The PNG outbreak was caused by an atypical El Tor strain harbouring a tandem repeat of the CTX prophage on chromosome II. Whole-genome sequence data, prophage structural analysis and the absence of the SXT integrative conjugative element was indicative that the PNG isolates were most closely related to strains …

Osteoblasts Are "Educated" By Crosstalk With Metastatic Breast Cancer Cells In The Bone Tumor Microenvironment., Alexus D. Kolb, Alison B. Shupp, Dimpi Mukhopadhyay, Frank C. Marini, Karen M. Bussard

Department of Cancer Biology Faculty Papers

INTRODUCTION: In a cancer-free environment in the adult, the skeleton continuously undergoes remodeling. Bone-resorbing osteoclasts excavate erosion cavities, and bone-depositing osteoblasts synthesize osteoid matrix that forms new bone, with no net bone gain or loss. When metastatic breast cancer cells invade the bone, this balance is disrupted. Patients with bone metastatic breast cancer frequently suffer from osteolytic bone lesions that elicit severe bone pain and fractures. Bisphosphonate treatments are not curative. Under ideal circumstances, osteoblasts would synthesize new matrix to fill in erosion cavities caused by osteoclasts, but this is not what occurs. Our prior evidence demonstrated that osteoblasts are …