Medical Microbiology Commons^™

Can Testing The Environment For Severe Acute Respiratory Coronavirus Virus 2 (Sars-Cov-2) Be A Signal For Coronavirus Disease 2019 (Covid-19) Cases Among Nursing Home Staff?, Gabrielle M. Gussin, Raveena D. Singh, Izabela Coimbra Ibraim, Raheeb Saavedra, Thomas T. Tjoa, Micaila Curtis, Kristine P. Nguyen, Ilhem Messaoudi, Susan S. Huang

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Prior to widespread COVID-19 vaccination, nursing homes were required to perform comprehensive weekly testing of staff. After the vaccine became available, testing became symptom-based for vaccinated staff despite continued waves of different severe acute respiratory coronavirus virus 2 (SARS-CoV-2) variants. Nursing homes need pragmatic, affordable strategies to identify SARS-CoV-2–positive staff because financial and job-related pressures drive reluctance to disclose mild symptoms. We sought to determine whether positive environmental samples for SARS-CoV-2 could serve as trigger for comprehensive staff testing in lieu of weekly testing of all staff.

Correlates Of Sars-Cov-2 Anti-Rbd Igg Antibody Titers Among Persons Experiencing Homelessness In Los Angeles, Adeline Nyamathi, Sanghyuk S. Shin, Brianna M. Doratt, Alexandria Jones-Patten, Benissa Salem, Lillian Gelberg, Darlene Lee, Dana Garfin, Kartik Yadav, Alicia H. Chang, Kathryn White, Nicholas Arce, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Objectives: People experiencing homelessness (PEH) have been especially impacted by the COVID-19 pandemic, likely due to increased vulnerabilities stemming from chronic diseases, substance use, and mental health conditions.

Design: A case–control study to assess the presence of antibodies against SARS-CoV-2 among PEH and associations with key variables.

Sample: A convenience sample of 97 PEH in Skid Row, Los Angeles.

Measurements: A structured questionnaire assessing socio-demographic, mental health, drug and alcohol use, health care access, pandemic stress, and other COVID-19-specific questions.

Results: We found high anti-receptor binding domain (RBD) IgG titers among five of 15 PEH who reported no prior COVID-19 …

Maternal Obesity Blunts Antimicrobial Responses In Fetal Monocytes, Suhas Sureshchandra, Brianna M. Doratt, Norma Mendza, Oleg Varlamov, Monica Rincon, Nicole E. Marshall, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Maternal pre-pregnancy (pregravid) obesity is associated with adverse outcomes for both mother and offspring. Amongst the complications for the offspring is increased susceptibility and severity of neonatal infections necessitating admission to the intensive care unit, notably bacterial sepsis and enterocolitis. Previous studies have reported aberrant responses to LPS and polyclonal stimulation by umbilical cord blood monocytes that were mediated by alterations in the epigenome. In this study, we show that pregravid obesity dysregulates umbilical cord blood monocyte responses to bacterial and viral pathogens. Specifically, interferon-stimulated gene expression and inflammatory responses to respiratory syncytial virus (RSV) and E. coli were significantly …

Sars-Cov-2 Infection And Seroconversion Rates In Healthcare Providers Prior To Covid-19 Vaccine Rollout, Sanghyuk S. Shin, Miriam Bender, Delphine C. Malherbe, Hannah Vasquez, Brianna M. Doratt, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Objective: A 6-month longitudinal surveillance study of asymptomatic healthcare providers (HCP) was carried out at a large urban academic medical center in the United States to assess whether their job occupation with higher exposure risks to SARS-CoV-2 would equate with higher risk of contracting COVID-19 at the beginning of the pandemic before COVID-19 vaccines were available.

Methods: A longitudinal cohort study design was used to collect and analyze immunological and virological monitoring data and self-report survey assessments of personal protective equipment (PPE) availability, adherence to infection control guidelines, and time spent on COVID-19 wards.

Results: Among 289 eligible participants, SARS-CoV-2 …

Single-Dose Vsv-Based Vaccine Protects Cynomolgus Macaques From Disease After Taï Forest Virus Infection, Paige Fletcher, Kyle L. O'Donnell, Brianna M. Doratt, Delphine C. Malherbe, Chad S. Clancy, Joseph F. Rhoderick, Friederike Feldmann, Patrick W. Hanley, Thomas G. Ksiazek, Thomas W. Geisbert, Ilhem Messaoudi, Andrea Marzi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Taï Forest virus (TAFV) is a lesser-known ebolavirus that causes lethal infections in chimpanzees and is responsible for a single human case. Limited research has been done on this human pathogen; however, with the recent emergence of filoviruses in West Africa, further investigation and countermeasure development against this virus is warranted. We developed a vesicular stomatitis virus (VSV)-based vaccine expressing the TAFV glycoprotein as the viral antigen and assessed it for protective efficacy in nonhuman primates (NHPs). Following a single high-dose vaccination, NHPs developed antigen-specific binding and neutralizing antibodies as well as modest T cell responses. Importantly, all vaccinated NHPs …

Transcriptional Profiling Of Immune Responses In Nhps After Low-Dose, Vsv-Based Vaccination Against Marburg Virus, Cecilia A. Prator, Brianna M. Doratt, Kyle L. O'Donnell, Justin Lack, Amanda N. Pinski, Stacy M. Ricklefs, Craig A. Martens, Ilhem Messaoudi, Andrea Marzi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Infection with Marburg virus (MARV), the causative agent of Marburg virus disease (MVD), results in haemorrhagic disease and high case fatality rates (>40%) in humans. Despite its public health relevance, there are no licensed vaccines or therapeutics to prevent or treat MVD. A vesicular stomatitis virus (VSV)-based vaccine expressing the MARV glycoprotein (VSV-MARV) is currently in clinical development. Previously, a single 10 million PFU dose of VSV-MARV administered 1–5 weeks before lethal MARV challenge conferred uniform protection in nonhuman primates (NHPs), demonstrating fast-acting potential. Additionally, our group recently demonstrated that even a low dose VSV-MARV (1000 PFU) protected NHPs …

Extracellular Vesicles Released After Cranial Radiation: An Insight Into An Early Mechanism Of Brain Injury., Suriyan Sukati, Jenni Ho, Luksana Chaiswing, Pradoldej Sompol, Harshul Pandit, Wendy Wei, Tadahide Izumi, Quan Chen, Heidi Weiss, Teresa Noel, Subbarao Bondada, D Allan Butterfield, Daret K St Clair

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Cranial radiation is important for treating both primary brain tumors and brain metastases. A potential delayed side effect of cranial radiation is neurocognitive function decline. Early detection of CNS injury might prevent further neuronal damage. Extracellular vesicles (EVs) have emerged as a potential diagnostic tool because of their unique membranous characteristics and cargos. We investigated whether EVs can be an early indicator of CNS injury by giving C57BJ/6 mice 10 Gy cranial IR. EVs were isolated from sera to quantify: 1) number of EVs using nanoparticle tracking analysis (NTA); 2) Glial fibrillary acidic protein (GFAP), an astrocyte marker; and 3) …

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 …

Interleukin-10 Suppression Enhances T-Cell Antitumor Immunity And Responses To Checkpoint Blockade In Chronic Lymphocytic Leukemia., J R Rivas, Y Liu, S S Alhakeem, J M Eckenrode, F Marti, J P Collard, Y Zhang, K A Shaaban, N Muthusamy, G C Hildebrandt, L Chen, J S Thorson, M Leggas, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

T-cell dysfunction is a hallmark of B-cell Chronic Lymphocytic Leukemia (CLL), where CLL cells downregulate T-cell responses through regulatory molecules including programmed death ligand-1 (PD-L1) and Interleukin-10 (IL-10). Immune checkpoint blockade (ICB) aims to restore T-cell function by preventing the ligation of inhibitory receptors like PD-1. However, most CLL patients do not respond well to this therapy. Thus, we investigated whether IL-10 suppression could enhance antitumor T-cell activity and responses to ICB. Since CLL IL-10 expression depends on Sp1, we utilized a novel, better tolerated analogue of the Sp1 inhibitor mithramycin (MTM

Chemotherapy-Induced Cognitive Impairment: Focus On The Intersection Of Oxidative Stress And Tnfα., Nicole G Rummel, Luksana Chaiswing, Subbarao Bondada, Daret K St Clair, D Allan Butterfield

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Chemotherapy-induced cognitive impairment (CICI) has been observed in a large fraction of cancer survivors. Although many of the chemotherapeutic drugs do not cross the blood-brain barrier, following treatment, the structure and function of the brain are altered and cognitive dysfunction occurs in a significant number of cancer survivors. The means by which CICI occurs is becoming better understood, but there still remain unsolved questions of the mechanisms involved. The hypotheses to explain CICI are numerous. More than 50% of FDA-approved cancer chemotherapy agents are associated with reactive oxygen species (ROS) that lead to oxidative stress and activate a myriad of …

Endophytes Of Brazilian Medicinal Plants With Activity Against Phytopathogens, Jucélia Iantas, Daiani Cristina Savi, Renata Da Silva Schibelbein, Sandriele Aparecida Noriler, Beatriz Marques Assad, Guilherme Dilarri, Henrique Ferreira, Jürgen Rohr, Jon S. Thorson, Khaled A. Shaaban, Chirlei Glienke

Pharmaceutical Sciences Faculty Publications

Plant diseases caused by phytopathogens are responsible for significant crop losses worldwide. Resistance induction and biological control have been exploited in agriculture due to their enormous potential. In this study, we investigated the antimicrobial potential of endophytic fungi of leaves and petioles of medicinal plants Vochysia divergens and Stryphnodendron adstringens located in two regions of high diversity in Brazil, Pantanal, and Cerrado, respectively. We recovered 1,304 fungal isolates and based on the characteristics of the culture, were assigned to 159 phenotypes. One isolate was selected as representative of each phenotype and studied for antimicrobial activity against phytopathogens. Isolates with better …

Targeted Oral Delivery Of Paclitaxel Using Colostrum-Derived Exosomes, Raghuram Kandimalla, Farrukh Aqil, Sara S. Alhakeem, Jeyaprakash Jeyabalan, Neha Tyagi, Ashish Agrawal, Jun Yan, Wendy Spencer, Subbarao Bondada, Ramesh C. Gupta

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Lung cancer is the leading cause of cancer-related deaths worldwide. Non-small-cell lung cancer (NSCLC) is the most common type accounting for 84% of all lung cancers. Paclitaxel (PAC) is a widely used drug in the treatment of a broad spectrum of human cancers, including lung. While efficacious, PAC generally is not well tolerated and its limitations include low aqueous solubility, and significant toxicity. To overcome the dose-related toxicity of solvent-based PAC, we utilized bovine colostrum-derived exosomes as a delivery vehicle for PAC for the treatment of lung cancer. Colostrum provided higher yield of exosomes and could be loaded with higher …

Report Of The Pathogenesis And Pathophysiology Of Lyme Disease Subcommittee Of The Hhs Tick Borne Disease Working Group, Sam T. Donta, Leith J. States, Wendy A. Adams, Troy Bankhead, Nicole Baumgarth, Monica E. Embers, Robert B. Lochhead, Brian Stevenson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

An understanding of the pathogenesis and pathophysiology of Lyme disease is key to the ultimate care of patients with Lyme disease. To better understand the various mechanisms underlying the infection caused by Borrelia burgdorferi, the Pathogenesis and Pathophysiology of Lyme Disease Subcommittee was formed to review what is currently known about the pathogenesis and pathophysiology of Lyme disease, from its inception, but also especially about its ability to persist in the host. To that end, the authors of this report were assembled to update our knowledge about the infectious process, identify the gaps that exist in our understanding of …

Piglet Immunization With A Spike Subunit Vaccine Enhances Disease By Porcine Epidemic Diarrhea Virus, Jieshi Yu, Chithra Sreenivasan, Tirth Uprety, Rongyuan Gao, Chen Huang, Ella J. Lee, Steven Lawson, Julie Nelson, Jane Christopher-Hennings, Radhey S. Kaushik, Eric Nelson, Diego G. Diel, Ben M. Hause, Feng Li, Dan Wang

Maxwell H. Gluck Equine Research Center Faculty Publications

Immunization with an insect cell lysate/baculovirus mixture containing recombinant porcine epidemic diarrhea virus (PEDV) spike protein induced high levels of neutralizing antibodies in both mice and piglets. However, immunization of piglets with this vaccine resulted in enhancement of disease symptoms and virus replication in vaccine recipients exposed to PEDV challenge. Thus, these observations demonstrate a previously unrecognized challenge of PEDV vaccine research, which has important implications for coronavirus vaccine development.

S. Gordonii-Produced Hydrogen Peroxide Modulates Mir-663a And Ccl20 Expression In Oral Epithelial Cells, Marshall Houston Maynard

Theses and Dissertations--Medical Sciences

The mechanisms through which a persistent recognition of commensal bacteria by oral epithelial cells (OECs) mitigates an uncontrolled inflammatory response of the oral mucosa remain unknown. CCL20 secretion by OECs in response to pathogenic bacteria is regulated by S. gordonii (Sg)-induced miR-663a; nevertheless, the mechanisms involved in these Sg-modulated responses remain to be elucidated. Since Sg is a hydrogen peroxide (H₂O₂) producer, and H₂O₂ has been shown to stimulate miRNA expression, we hypothesized that H₂O₂ could be involved in Sg-induced miR663a and CCL20 responses. Expression of miR663a …

Neurotropic Lineage Iii Strains Of Listeria Monocytogenes Disseminate To The Brain Without Reaching High Titer In The Blood, Taylor E. Senay, Jessica L. Ferrell, Filip G. Garrett, Taylor M. Albrecht, Jooyoung Cho, Katie L. Alexander, Tanya Myers-Morales, Olivia F. Grothaus, Sarah E. F. D'Orazio

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Listeria monocytogenes is thought to colonize the brain using one of three mechanisms: direct invasion of the blood-brain barrier, transportation across the barrier by infected monocytes, and axonal migration to the brain stem. The first two pathways seem to occur following unrestricted bacterial growth in the blood and thus have been linked to immunocompromise. In contrast, cell-to-cell spread within nerves is thought to be mediated by a particular subset of neurotropic L. monocytogenes strains. In this study, we used a mouse model of foodborne transmission to evaluate the neurotropism of several L. monocytogenes isolates. Two strains preferentially colonized the brain …

Cell Cycle Regulation In Macrophages And Susceptibility To Hiv-1, Isabella A. T. M. Ferreira, James Zachary Porterfield, Ravindra K. Gupta, Petra Mlcochova

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Macrophages are the first line of defence against invading pathogens. They play a crucial role in immunity but also in regeneration and homeostasis. Their remarkable plasticity in their phenotypes and function provides them with the ability to quickly respond to environmental changes and infection. Recent work shows that macrophages undergo cell cycle transition from a G0/terminally differentiated state to a G1 state. This G0-to-G1 transition presents a window of opportunity for HIV-1 infection. Macrophages are an important target for HIV-1 but express high levels of the deoxynucleotide-triphosphate hydrolase SAMHD1, which restricts viral DNA synthesis by decreasing levels of dNTPs. While …

Aging Induces B Cell Defects And Decreased Antibody Responses To Influenza Infection And Vaccination, Daniela Frasca, Bonnie B. Blomberg

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Background: Aging is characterized by a progressive decline in the capacity of the immune system to fight influenza virus infection and to respond to vaccination. Among the several factors involved, in addition to increased frailty and high-risk conditions, the age-associated decrease in cellular and humoral immune responses plays a relevant role. This is in large part due to inflammaging, the chronic low-grade inflammatory status of the elderly, associated with intrinsic inflammation of the immune cells and decreased immune function.

Results: Aging is usually associated with reduced influenza virus-specific and influenza vaccine-specific antibody responses but some elderly individuals with higher pre-exposure …

Dna Methylation By Restriction Modification Systems Affects The Global Transcriptome Profile In Borrelia Burgdorferi, Timothey Casselli, Yvonne Tourand, Adam Scheidegger, William K. Arnold, Anna Proulx, Brian Stevenson, Catherine A. Brissette

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Prokaryote restriction modification (RM) systems serve to protect bacteria from potentially detrimental foreign DNA. Recent evidence suggests that DNA methylation by the methyltransferase (MTase) components of RM systems can also have effects on transcriptome profiles. The type strain of the causative agent of Lyme disease, Borrelia burgdorferi B31, possesses two RM systems with N6-methyladenosine (m6A) MTase activity, which are encoded by the bbe02 gene located on linear plasmid lp25 and bbq67 on lp56. The specific recognition and/or methylation sequences had not been identified for either of these B. burgdorferi MTases, and it was not previously known whether these RM …

Floxed-Cassette Allelic Exchange Mutagenesis Enables Markerless Gene Deletion In Chlamydia Trachomatis And Can Reverse Cassette-Induced Polar Effects, Gabrielle Keb, Robert Hayman, Kenneth A. Fields

Microbiology, Immunology, and Molecular Genetics Faculty Publications

As obligate intracellular bacteria, Chlamydia spp. have evolved numerous, likely intricate, mechanisms to create and maintain a privileged intracellular niche. Recent progress in elucidating and characterizing these processes has been bolstered by the development of techniques enabling basic genetic tractability. Florescence-reported allelic exchange mutagenesis (FRAEM) couples chromosomal gene deletion with the insertion of a selection cassette encoding antibiotic resistance and green fluorescent protein (GFP). Similar to other bacteria, many chlamydial genes exist within polycistronic operons, raising the possibility of polar effects mediated by insertion cassettes. Indeed, FRAEM-mediated deletion of Chlamydia trachomatis tmeA negatively impacts the expression of tmeB. We …

Antibody Epitope Specificity For Dsdna Phosphate Backbone Is An Intrinsic Property Of The Heavy Chain Variable Germline Gene Segment Used, Tatjana Srdic-Rajic, Heinz Kohler, Vladimir Jurisic, Radmila Metlas

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Analysis of protein sequences by the informational spectrum method (ISM) enables characterization of their specificity according to encoded information represented with defined frequency (F). Our previous data showed that F(0.367) is characteristic for variable heavy chain (VH) domains (a combination of variable (V), diversity (D) and joining (J) gene segments) of the anti-phosphocholine (PC) T15 antibodies and mostly dependent on the CDR2 region, a site for PC phosphate group binding. Because the T15 dsDNA-reactive U4 mutant also encodes F(0.367), we hypothesized that the same frequency may also be characteristic for anti-DNA antibodies. Data obtained from an analysis of 60 spontaneously …

Detection Of (1,3)-Β-D-Glucan In Cerebrospinal Fluid In Histoplasma Meningitis, Thein Myint, Felicia C. Chow, Karen C. Bloch, Luke Raymond-Guillen, Thomas E. Davis, Patty W. Wright, Laila Woc-Colburn, Raed N. Khairy, Alan C. Street, Tomotaka Yamamoto, Amanda Albers, L. Joseph Wheat, Chadi A. Hage

Internal Medicine Faculty Publications

The diagnosis of central nervous system (CNS) histoplasmosis is often difficult. Although cerebrospinal fluid (CSF) (1,3)-β-d-glucan (BDG) is available as a biological marker for the diagnosis of fungal meningitis, there are limited data on its use for the diagnosis of Histoplasma meningitis. We evaluated CSF BDG detection, using the Fungitell assay, in patients with CNS histoplasmosis and controls. A total of 47 cases and 153 controls were identified. The control group included 13 patients with a CNS fungal infection other than histoplasmosis. Forty-nine percent of patients with CNS histoplasmosis and 43.8% of controls were immunocompromised. The median CSF …

Alterations In Platelet Secretion Differentially Affect Thrombosis And Hemostasis, Smita Joshi, Meenakshi Banerjee, Jinchao Zhang, Akhil Kesaraju, Irina D. Pokrovskaya, Brian Storrie, Sidney W. Whiteheart

Molecular and Cellular Biochemistry Faculty Publications

We genetically manipulated the major platelet vesicle-associated membrane proteins (VAMP2, VAMP3, and VAMP8) to create mice with varying degrees of disrupted platelet secretion. As previously shown, loss of VAMP8 reduced granule secretion, and this defect was exacerbated by further deletion of VAMP2 and VAMP3. VAMP2^Δ3^Δ8^−/− platelets also had reduced VAMP7. Loss of VAMP2 and VAMP3 (VAMP2^Δ3^Δ) had a minimal impact on secretion when VAMP7 and VAMP8 were present. Integrin αIIbβ3 activation and aggregation were not affected, although spreading was reduced in VAMP2^Δ3^Δ8^−/− platelets. Using these mice …

Interfering With Dna Decondensation As A Strategy Against Mycobacteria, Enzo M. Scutigliani, Edwin R. Scholl, Anita E. Grootemaat, Sadhana Khanal, Jakub A. Kochan, Przemek M. Krawczyk, Eric A. Reits, Atefeh Garzan, Huy X. Ngo, Keith D. Green, Sylvie Garneau-Tsodikova, Jan M. Ruijter, Henk A. Van Veen, Nicole N. Van Der Wel

Pharmaceutical Sciences Faculty Publications

Tuberculosis is once again a major global threat, leading to more than 1 million deaths each year. Treatment options for tuberculosis patients are limited, expensive and characterized by severe side effects, especially in the case of multidrug-resistant forms. Uncovering novel vulnerabilities of the pathogen is crucial to generate new therapeutic strategies. Using high resolution microscopy techniques, we discovered one such vulnerability of Mycobacterium tuberculosis. We demonstrate that the DNA of M. tuberculosis can condense under stressful conditions such as starvation and antibiotic treatment. The DNA condensation is reversible and specific for viable bacteria. Based on these observations, we hypothesized …

The Conquest Of Pus -- A History Of Bitumen, Creosote And Carbolic Acid, Charles T. Ambrose

Microbiology, Immunology, and Molecular Genetics Faculty Publications

In the Western world from antiquity on, open wounds were treated topically with petroleum-derived substances, such as bitumen, asphalt, pitch, and tar. The immediate aim was to stifle bleeding and ease pain but a potential benefit was preventing local corruption with pus formation. In the early 19th century, creosote was recovered from bitumen and found to reduce suppuration. Carbolic acid was later isolated from creosote and recognized as an underlying active agent. In the 1860s, carbolic acid was first employed by Jules Lemaire to treat local skin infections and later by Joseph Lister to prevent the suppuration in compound fractures. …

Transcriptomic Insights On The Virulence-Controlling Csra, Badr, Rpon, And Rpos Regulatory Networks In The Lyme Disease Spirochete, William K. Arnold, Christina R. Savage, Kathryn G. Lethbridge, Trever C. Smith, Catherine A. Brisette, Janakiram Seshu, Brian Stevenson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Borrelia burgdorferi, the causative agent of Lyme disease, survives in nature through a cycle that alternates between ticks and vertebrates. To facilitate this defined lifestyle, B. burgdorferi has evolved a gene regulatory network that ensures transmission between those hosts, along with specific adaptations to niches within each host. Several regulatory proteins are known to be essential for the bacterium to complete these critical tasks, but interactions between regulators had not previously been investigated in detail, due to experimental uses of different strain backgrounds and growth conditions. To address that deficit in knowledge, the transcriptomic impacts of four critical …

Novel Role Of Prostate Apoptosis Response-4 Tumor Suppressor In B-Cell Chronic Lymphocytic Leukemia, Mary Kathryn Mckenna, Sunil K. Noothi, Sara S. Alhakeem, Karine Z. Oben, Joseph T. Greene, Rajeswaran Mani, Kathryn L. Perry, James P. Collard, Jacqueline R. Rivas, Gerhard C. Hildebrandt, Roger A. Fleischman, Eric B. Durbin, John C. Byrd, Chi Wang, Natarajan Muthusamy, Vivek M. Rangnekar, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Prostate apoptosis response-4 (Par-4), a proapoptotic tumor suppressor protein, is downregulated in many cancers including renal cell carcinoma, glioblastoma, endometrial, and breast cancer. Par-4 induces apoptosis selectively in various types of cancer cells but not normal cells. We found that chronic lymphocytic leukemia (CLL) cells from human patients and from Eµ-Tcl1 mice constitutively express Par-4 in greater amounts than normal B-1 or B-2 cells. Interestingly, knockdown of Par-4 in human CLL-derived Mec-1 cells results in a robust increase in p21/WAF1 expression and decreased growth due to delayed G1-to-S cell-cycle transition. Lack of Par-4 also increased the expression of p21 and …

Chronic Lymphocytic Leukemia-Derived Il-10 Suppresses Antitumor Immunity., Sara S Alhakeem, Mary K Mckenna, Karine Z Oben, Sunil K Noothi, Jacqueline R Rivas, Gerhard C Hildebrandt, Roger A Fleischman, Vivek M Rangnekar, Natarajan Muthusamy, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Chronic lymphocytic leukemia (CLL) patients progressively develop an immunosuppressive state. CLL patients have more plasma IL-10, an anti-inflammatory cytokine, than healthy controls. In vitro human CLL cells produce IL-10 in response to BCR cross-linking. We used the transgenic Eμ-T cell leukemia oncogene-1 (

Borrelia Burgdorferi Spovg Dna- And Rna-Binding Protein Modulates The Physiology Of The Lyme Disease Spirochete, Christina R. Savage, Brandon L. Jutras, Aaron Bestor, Kit Tilly, Patricia A. Rosa, Yvonne Tourand, Philip E. Stewart, Catherine A. Brissette, Brian Stevenson

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The SpoVG protein of Borrelia burgdorferi, the Lyme disease spirochete, binds to specific sites of DNA and RNA. The bacterium regulates transcription of spoVG during the natural tick-mammal infectious cycle and in response to some changes in culture conditions. Bacterial levels of spoVG mRNA and SpoVG protein did not necessarily correlate, suggesting that posttranscriptional mechanisms also control protein levels. Consistent with this, SpoVG binds to its own mRNA, adjacent to the ribosome-binding site. SpoVG also binds to two DNA sites in the glpFKD operon and to two RNA sites in glpFKD mRNA; that operon encodes genes necessary for glycerol catabolism …

Bioprospecting Deep-Sea Actinobacteria For Novel Anti-Infective Natural Products, Dongbo Xu, Linna Han, Chunhui Li, Qi Cao, Duolong Zhu, Nolan H. Barrett, Dedra Harmody, Jing Chen, Haining Zhu, Peter J. Mccarthy, Xingmin Sun, Guojun Wang

Molecular and Cellular Biochemistry Faculty Publications

The global prevalence of drug resistance has created an urgent need for the discovery of novel anti-infective drugs. The major source of antibiotics in current clinical practice is terrestrial actinobacteria; the less-exploited deep-sea actinobacteria may serve as an unprecedented source of novel natural products. In this study, we evaluated 50 actinobacteria strains derived from diverse deep water sponges and environmental niches for their anti-microbial activities against a panel of pathogens including Candida albicans, Clostridium difficile, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA), and Pseudomonas aeruginosa. More than half of the tested strains (27) were identified as …