Medical Microbiology Commons^™

Synergy Of Two Low-Affinity Nlss Determines The High Avidity Of Influenza A Virus Nucleoprotein Np For Human Importin Α Isoforms., Wei Wu, Rajeshwer S. Sankhala, Tyler J Florio, Lixin Zhou, Nhan L.T. Nguyen, Ravi K. Lokareddy, Gino Cingolani, Nelly Panté

Department of Biochemistry and Molecular Biology Faculty Papers

The influenza A virus nucleoprotein (NP) is an essential multifunctional protein that encapsidates the viral genome and functions as an adapter between the virus and the host cell machinery. NPs from all strains of influenza A viruses contain two nuclear localization signals (NLSs): a well-studied monopartite NLS1 and a less-characterized NLS2, thought to be bipartite. Through site-directed mutagenesis and functional analysis, we found that NLS2 is also monopartite and is indispensable for viral infection. Atomic structures of importin α bound to two variants of NLS2 revealed NLS2 primarily binds the major-NLS binding site of importin α, unlike NLS1 that associates …

Taking Control: Reorganization Of The Host Cytoskeleton By Chlamydia., Jordan Wesolowski, Fabienne Paumet

Department of Microbiology and Immunology Faculty Papers

Both actin and microtubules are major cytoskeletal elements in eukaryotic cells that participate in many cellular processes, including cell division and motility, vesicle and organelle movement, and the maintenance of cell shape. Inside its host cell, the human pathogen Chlamydia trachomatis manipulates the cytoskeleton to promote its survival and enhance its pathogenicity. In particular, Chlamydia induces the drastic rearrangement of both actin and microtubules, which is vital for its entry, inclusion structure and development, and host cell exit. As significant progress in Chlamydia genetics has greatly enhanced our understanding of how this pathogen co-opts the host cytoskeleton, we will discuss …

Ablation Of An Ovarian Tumor Family Deubiquitinase Exposes The Underlying Regulation Governing The Plasticity Of Cell Cycle Progression In Toxoplasma Gondii, Animesh Dhara, Rodrigo De Paula Baptista, Jessica C. Kissinger, Ernest Charles Snow, Anthony P. Sinai

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The Toxoplasma genome encodes the capacity for distinct architectures underlying cell cycle progression in a life cycle stage-dependent manner. Replication in intermediate hosts occurs by endodyogeny, whereas a hybrid of schizogony and endopolygeny occurs in the gut of the definitive feline host. Here, we characterize the consequence of the loss of a cell cycle-regulated ovarian tumor (OTU family) deubiquitinase, OTUD3A of Toxoplasma gondii (TgOTUD3A; TGGT1_258780), in T. gondii tachyzoites. Rather than the mutation being detrimental, mutant parasites exhibited a fitness advantage, outcompeting the wild type. This phenotype was due to roughly one-third of TgOTUD3A-knockout (TgOTUD3A-KO) tachyzoites exhibiting deviations from endodyogeny …

Suppression Of Mrnas Encoding Cd63 Family Tetraspanins From The Carcinogenic Liver Fluke Opisthorchis Viverrini Results In Distinct Tegument Phenotypes., Sujittra Chaiyadet, Watchara Krueajampa, Wiphawi Hipkaeo, Yada Plosan, Supawadee Piratae, Javier Sotillo, Michael Smout, Banchob Sripa, Paul J Brindley, Alex Loukas, Thewarach Laha

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The liver fluke Opisthorchis viverrini infects 10 million people in Southeast Asia and causes cholangiocarcinoma (CCA). Fluke secreted and tegumental proteins contribute to the generation of a tumorigenic environment and are targets for drug and vaccine-based control measures. Herein, we identified two tetraspanins belonging to the CD63 family (Ov-TSP-2 and Ov-TSP-3) that are abundantly expressed in the tegument proteome of O. viverrini. Ov-tsp-2 and tsp-3 transcripts were detected in all developmental stages of O. viverrini. Protein fragments corresponding to the large extracellular loop (LEL) of each TSP were produced in recombinant form and antibodies were raised in rabbits. Ov-TSP-2 and …

A Coal Miner With Weakness, Fatigue, Nausea, Fever, Chills, Night Sweats And Dyspnea, Larry Nichols

Marshall Journal of Medicine

Delayed or missed diagnoses are a constant hazard in primary care. This is the case report of a 51-year-old coal miner, who presented as an ambulatory outpatient on a Friday with weakness, fatigue, nausea, fever, chills, night sweats and dyspnea. Chest x-ray on Saturday showed pneumonia and pleural effusion, while blood testing showed renal failure, but these results were not known by his physician until Monday, when he was hospitalized with severe sepsis due to fatal Austrian syndrome of pneumococcal pneumonia, endocarditis and meningitis. Analysis of the delay of diagnosis in this case suggests the possibility that a weekend effect …

Differentiation And Protective Capacity Of Virus-Specific Cd8, Vesselin T. Tomov, Olesya Palko, Chi Wai Lau, Ajinkya Pattekar, Yuhang Sun, Ralitza Tacheva, Bertram Bengsch, Sasikanth Manne, Gabriela L. Cosma, Laurence C. Eisenlohr, Timothy J. Nice, Herbert W. Virgin, E. John Wherry

Department of Microbiology and Immunology Faculty Papers

Noroviruses can establish chronic infections with active viral shedding in healthy humans but whether persistence is associated with adaptive immune dysfunction is unknown. We used genetically engineered strains of mouse norovirus (MNV) to investigate CD8⁺ T cell differentiation during chronic infection. We found that chronic infection drove MNV-specific tissue-resident memory (Trm) CD8⁺ T cells to a differentiation state resembling inflationary effector responses against latent cytomegalovirus with only limited evidence of exhaustion. These MNV-specific Trm cells remained highly functional yet appeared ignorant of ongoing viral replication. Pre-existing MNV-specific Trm cells provided partial protection against chronic infection but largely ceased …

Human Herpesvirus 8 Infects And Replicates In Langerhans Cells And Interstitial Dermal Dendritic Cells And Impairs Their Function., Giovanna Rappocciolo, Mariel Jais, Paolo A Piazza, Diana C Delucia, Frank J Jenkins, Charles R Rinaldo

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The predominant types of dendritic cells (DC) in the skin and mucosa are Langerhans cells (LC) and interstitial dermal DC (iDDC). LC and iDDC process cutaneous antigens and migrate out of the skin and mucosa to the draining lymph nodes to present antigens to T and B cells. Because of the strategic location of LC and iDDC and the ability of these cells to capture and process pathogens, we hypothesized that they could be infected with human herpesvirus 8 (HHV-8) (Kaposi's sarcoma [KS]-associated herpesvirus) and have an important role in the development of KS. We have previously shown that HHV-8 …

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 …

T-Cell Responses Targeting Hiv Nef Uniquely Correlate With Infected Cell Frequencies After Long-Term Antiretroviral Therapy., Allison S Thomas, Kimberley L Jones, Rajesh T Gandhi, Deborah K Mcmahon, Joshua C Cyktor, Dora Chan, Szu-Han Huang, Ronald Truong, Alberto Bosque, Amanda B Macedo, Colin Kovacs, Erika Benko, Joseph J Eron, Ronald J Bosch, Christina M Lalama, Samuel Simmens, Bruce D Walker, John W Mellors, R Brad Jones

Microbiology, Immunology, and Tropical Medicine Faculty Publications

HIV-specific CD8+ T-cell responses limit viral replication in untreated infection. After the initiation of antiretroviral therapy (ART), these responses decay and the infected cell population that remains is commonly considered to be invisible to T-cells. We hypothesized that HIV antigen recognition may persist in ART-treated individuals due to low-level or episodic protein expression. We posited that if persistent recognition were occurring it would be preferentially directed against the early HIV gene products Nef, Tat, and Rev as compared to late gene products, such as Gag, Pol, and Env, which have higher barriers to expression. Using a primary cell model of …

Evaluating A Preoperative Protocol That Includes Magnetic Resonance Imaging For Lymph Node Metastasis In The Cholangiocarcinoma Screening And Care Program (Cascap) In Thailand., Metha Songthamwat, Nittaya Chamadol, Narong Khuntikeo, Jadsada Thinkhamrop, Supinda Koonmee, Nathaphop Chaichaya, Jeffrey Bethony, Bandit Thinkhamrop

Microbiology, Immunology, and Tropical Medicine Faculty Publications

BACKGROUND: Treatment planning especially liver resection in cholangiocarcinoma (CCA) depends on the extension of tumor and lymph node metastasis which is included as a key criterion for operability. Magnetic resonance imaging (MRI) offers a rapid and powerful tool for the detection of lymph node metastasis (LNM) and in the current manuscript is assessed as a critical tool in the preoperative protocol for liver resection for treatment of CCA. However, the accuracy of MRI to detect LNM from CCA had yet to be comprehensively evaluated.

METHODS: The accuracy of MRI to detect LNM was assessed in a cohort of individuals with …

Characterization Of Different Molecular Markers For Identification Of Salmonella Enterica Serovar Typhi In Pakistani Population, Faizan Muttiullah, Fida Muhammad Khan, Fakhar-I- Abbas, Sabiha Shamim

Journal of Bioresource Management

Typhoid is caused by Salmonella enterica serovar Typhi that is usually diagnosed by using serologic and immuno-chromatographic techniques in developing counties including Pakistan, which is thought to be an unreliable diagnostic method. For accurate diagnosis we used molecular techniques to amplify 204 bp StyR-36 and 498 bp flagellin gene for the identification of Salmonella enterica serovar Typhi. This study was done on 58 individuals diagnosed positive of typhoid via serologic tests and 50 healthy individuals as a control group. Success rate of amplification for flagellin gene was 77.58% while that for StyR-36 gene was 68.97% showing that flagellin gene primer …

Silver Oxide Coatings With High Silver-Ion Elution Rates And Characterization Of Bactericidal Activity., Sarah S Goderecci, Eric Kaiser, Michael Yanakas, Zachary Norris, Jeffrey Scaturro, Robert Oszust, Clarence D Medina, Fallon Waechter, Min Heon, Robert R Krchnavek, Lei Yu, Samuel E Lofland, Renee M Demarest, Gregory A Caputo, Jeffrey D Hettinger

Rowan-Virtua School of Osteopathic Medicine Departmental Research

This paper reports the synthesis and characterization of silver oxide films for use as bactericidal coatings. Synthesis parameters, dissolution/elution rate, and bactericidal efficacy are reported. Synthesis conditions were developed to create AgO, Ag₂O, or mixtures of AgO and Ag₂O on surfaces by reactive magnetron sputtering. The coatings demonstrate strong adhesion to many substrate materials and impede the growth of all bacterial strains tested. The coatings are effective in killing Escherichia coli and Staphylococcus aureus, demonstrating a clear zone-of-inhibition against bacteria growing on solid media and the ability to rapidly inhibit bacterial growth in planktonic culture. Additionally, the coatings exhibit very …

Anti-Herv-K (Hml-2) Capsid Antibody Responses In Hiv Elite Controllers., Miguel De Mulder, Devi Sengupta, Steven G Deeks, Jeffrey N Martin, Christopher D Pilcher, Frederick M Hecht, Jonah B Sacha, Douglas F Nixon, Henri-Alexandre Michaud

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background

Human endogenous retroviruses (HERVs) comprise approximately 8% of the human genome and while the majority are transcriptionally silent, the most recently integrated HERV, HERV-K (HML-2), remains active. During HIV infection, HERV-K (HML-2) specific mRNA transcripts and viral proteins can be detected. In this study, we aimed to understand the antibody response against HERV-K (HML-2) Gag in the context of HIV-1 infection.

Results

We developed an ELISA assay using either recombinant protein or 164 redundant “15mer” HERV-K (HML-2) Gag peptides to test sera for antibody reactivity. We identified a total of eight potential HERV-K (HML-2) Gag immunogenic domains: two on …

Improving Type And Screen Specimen Collection Prior To Elective Surgery, Nordx Blood Bank Staff, Haley Pelletier, Suneela Nayak, Stephen Tyzik, Ruth Hanselman

MaineHealth Maine Medical Center

To avoid delays in the availability of compatible blood for elective surgery patients requiring transfusion, a type and screen specimen should be completed at least 24 hours prior to surgery. Baseline metrics in an acute care inpatient blood bank demonstrated a significant number of cases with no type or screen completed.

The objective of this KPI was to prevent any delays in providing compatible blood products to scheduled surgical patients. Several internal and external system issues were identified as a result of a root cause analysis and a number of actions were initiated.

Outcomes have been positive. Data collection post …

Stromal Cyclin D1 Promotes Heterotypic Immune Signaling And Breast Cancer Growth, Timothy G. Pestell, Xuanmao Jiao, Mukesh Kumar, Amy R. Peck, Marco Prisco, Shengqiong Deng, Zhiping Li, Adam Ertel, Matthew C. Casimiro, Xiaoming Ju, Agnese Di Rocco, Gabriele Di Sante, Sanjay Katiyar, Alison Shupp, Michael P. Lisanti, Pooja Jain, Kongming Wu, Hallgeir Rui, Douglas Craig Hooper, Zuoren Yu, Aaron R. Goldman, David W. Speicher, Lisa Laury-Kleintop, Richard G. Pestell

Department of Cancer Biology Faculty Papers

The cyclin D1 gene encodes the regulatory subunit of a holoenzyme that drives cell autonomous cell cycle progression and proliferation. Herein we show cyclin D1 abundance is increased > 30-fold in the stromal fibroblasts of patients with invasive breast cancer, associated with poor outcome. Cyclin D1 transformed hTERT human fibroblast to a cancer-associated fibroblast phenotype. Stromal fibroblast expression of cyclin D1 (cyclin D1^Stroma) in vivo, enhanced breast epithelial cancer tumor growth, restrained apoptosis, and increased autophagy. Cyclin D1^Stroma had profound effects on the breast tumor microenvironment increasing the recruitment of F4/80⁺ and CD11b⁺ macrophages and increasing …

Structure-Based Design Of Hepatitis C Virus Vaccines That Elicit Neutralizing Antibody Responses To A Conserved Epitope, Brian G. Pierce, Elisabeth N. Boucher, Kurt H. Piepenbrink, Monir Ejemal, Chelsea A. Rapp, William D. Thomas Jr, Eric J. Sundberg, Zhiping Weng, Yang Wang

Food for Health: Publications

Despite recent advances in therapeutic options, hepatitis C virus (HCV) remains a severe global disease burden, and a vaccine can substantially reduce its incidence. Due to its extremely high sequence variability, HCV can readily escape the immune response; thus, an effective vaccine must target conserved, functionally important epitopes. Using the structure of a broadly neutralizing antibody in complex with a conserved linear epitope from the HCV E2 envelope glycoprotein (residues 412 to 423; epitope I), we performed structure-based design of immunogens to induce antibody responses to this epitope. This resulted in epitope-based immunogens based on a cyclic defensin protein, as …

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 …

Revisiting Neutrophil Responses To Toll-Like Receptor 4 : Influence Of Ligand Structures And Cellular Environments., Shuvasree Sengupta

Electronic Theses and Dissertations

Neutrophils respond to bacterial LPS through Toll-like receptor 4 (TLR4), which activates or potentiates immune defensive functions and prolongs cell survival. Activation of TLR4 signaling in neutrophils is beneficial for effective clearance of LPS-bearing Gram-negative bacteria, but may also drive aberrant inflammation if not stringently regulated. The regulatory processes by which neutrophil functions are calibrated to respond appropriately to different LPS-bearing bacteria are incompletely understood. Described here are investigations that reveal an unexpected sensitivity of TLR4 in neutrophils to small changes in LPS structure typical of various Gram-negative bacteria, including those that are dangerously virulent (Escherichia coli and Salmonella …

The Global Alliance For Infections In Surgery: Defining A Model For Antimicrobial Stewardship-Results From An International Cross-Sectional Survey, M Sartelli, F Labricciosa, P Barbadoro, L Pagani, L Ansaloni, Rifat Latifi, N Shafiq, K Koike, I Kozlovska, A Kumar, L Lagunes, Rifat Latifi, J Lee, N Shafiq

NYMC Faculty Publications

BACKGROUND: Antimicrobial Stewardship Programs (ASPs) have been promoted to optimize antimicrobial usage and patient outcomes, and to reduce the emergence of antimicrobial-resistant organisms. However, the best strategies for an ASP are not definitively established and are likely to vary based on local culture, policy, and routine clinical practice, and probably limited resources in middle-income countries. The aim of this study is to evaluate structures and resources of antimicrobial stewardship teams (ASTs) in surgical departments from different regions of the world. METHODS: A cross-sectional web-based survey was conducted in 2016 on 173 physicians who participated in the AGORA (Antimicrobials: A Global …

The Feoabc Locus Of Yersinia Pestis Likely Has Two Promoters Causing Unique Iron Regulation, Lauren O'Connor, Jacqueline D. Fetherston, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The FeoABC ferrous transporter is a wide-spread bacterial system. While the feoABC locus is regulated by a number of factors in the bacteria studied, we have previously found that regulation of feoABC in Yersinia pestis appears to be unique. None of the non-iron responsive transcriptional regulators that control expression of feoABC in other bacteria do so in Y. pestis. Another unique factor is the iron and Fur regulation of the Y. pestis feoABC locus occurs during microaerobic but not aerobic growth. Here we show that this unique iron-regulation is not due to a unique aspect of the Y. pestis …