Pathology Commons^™

Targeted Repression Of Topa By Crispri Reveals A Critical Function For Balanced Dna Topoisomerase I Activity In The Chlamydia Trachomatis Developmental Cycle, Li Shen, Leiqiong Gao, Abigail R. Swoboda, Scot P. Ouellette

School of Medicine Faculty Publications

Chlamydia trachomatis is an obligate intracellular bacterium that is responsible for the most prevalent bacterial sexually transmitted infection. Changes in DNA topology in this pathogen have been linked to its pathogenicity-associated developmental cycle. Here, evidence is provided that the balanced activity of DNA topoisomerases contributes to controlling Chlamydia developmental processes. Utilizing catalytically inactivated Cas12 (dCas12)-based clustered regularly interspaced short palindromic repeats interference (CRISPRi) technology, we demonstrate targeted knockdown of chromosomal topA transcription in C. trachomatis without detected toxicity of dCas12. Repression of topA impaired the developmental cycle of C. trachomatis mostly through disruption of its differentiation from a replicative form …

Metabolism Shapes Immune Responses To Staphylococcus Aureus., Prabhakar Arumugam, Tammy Kielian

Journal Articles: Pathology and Microbiology

BACKGROUND: Staphylococcus aureus (S. aureus) is a common cause of hospital- and community-acquired infections that can result in various clinical manifestations ranging from mild to severe disease. The bacterium utilizes different combinations of virulence factors and biofilm formation to establish a successful infection, and the emergence of methicillin- and vancomycin-resistant strains introduces additional challenges for infection management and treatment.

SUMMARY: Metabolic programming of immune cells regulates the balance of energy requirements for activation and dictates pro- versus anti-inflammatory function. Recent investigations into metabolic adaptations of leukocytes and S. aureus during infection indicate that metabolic crosstalk plays a crucial role in …

Metabolic Diversity Of Human Macrophages: Potential Influence On Staphylococcus Aureus Intracellular Survival, Blake P. Bertrand, Dhananjay Shinde, Vinai C. Thomas, Marvin Whiteley, Carolyn B. Ibberson, Tammy Kielian

Journal Articles: Pathology and Microbiology

Staphylococcus aureus is a leading cause of medical device-associated biofilm infections. This is influenced by the ability of S. aureus biofilm to evade the host immune response, which is partially driven by the anti-inflammatory cytokine interleukin-10 (IL-10). Here, we show that treatment of human monocyte-derived macrophages (HMDMs) with IL-10 enhanced biofilm formation, suggesting that macrophage anti-inflammatory programming likely plays an important role during the transition from planktonic to biofilm growth. To identify S. aureus genes that were important for intracellular survival in HMDMs and how this was affected by IL-10, transposon sequencing was performed. The size of the S. aureus …

Elucidating Granulocytic Myeloid-Derived Suppressor Cell Heterogeneity During Staphylococcus Aureus Biofilm Infection, Blake P. Bertrand, Cortney E. Heim, Scott A. Koepsell, Tammy Kielian

Journal Articles: Pathology and Microbiology

Myeloid-derived suppressor cells (MDSCs) are pathologically activated immature myeloid cells with immunosuppressive activity that expand during chronic inflammation, such as cancer and prosthetic joint infection (PJI). Myeloid-derived suppressor cells can be broadly separated into 2 populations based on surface marker expression and function: monocytic myeloid-derived suppressor cells (M-MDSCs) and granulocytic myeloid-derived suppressor cells (G-MDSCs). Granulocytic myeloid-derived suppressor cells are the most abundant leukocyte infiltrate during PJI; however, how this population is maintained in vivo and cellular heterogeneity is currently unknown. In this study, we identified a previously unknown population of Ly6G+Ly6C+F4/80+MHCII+ MDSCs during PJI that displayed immunosuppressive properties ex vivo. …

Bacteria Commonly Associated With Central Nervous System Catheter Infections Elicit Distinct Csf Proteome Signatures, Matthew K. Beaver, Dragana Noe, Ishwor Thapa, Hesham Ali, Jessica Snowden, Tammy Kielian, Gwenn Skar

Journal Articles: Pathology and Microbiology

Background: Cerebrospinal fluid (CSF) shunt infection is a common and devastating complication of the treatment of hydrocephalus. Timely and accurate diagnosis is essential as these infections can lead to long-term neurologic consequences including seizures, decreased intelligence quotient (IQ) and impaired school performance in children. Currently the diagnosis of shunt infection relies on bacterial culture; however, culture is not always accurate since these infections are frequently caused by bacteria capable of forming biofilms, such as Staphylococcus epidermidis, Cutibacterium acnes, and Pseudomonas aeruginosa resulting in few planktonic bacteria detectable in the CSF. Therefore, there is a critical need to identify a …

Advances In Antimicrobial Peptide Discovery Via Machine Learning And Delivery Via Nanotechnology, Alexa Sowers, Guangshun Wang, Malcolm Xing, Bingyun Li

Journal Articles: Pathology and Microbiology

Antimicrobial peptides (AMPs) have been investigated for their potential use as an alternative to antibiotics due to the increased demand for new antimicrobial agents. AMPs, widely found in nature and obtained from microorganisms, have a broad range of antimicrobial protection, allowing them to be applied in the treatment of infections caused by various pathogenic microorganisms. Since these peptides are primarily cationic, they prefer anionic bacterial membranes due to electrostatic interactions. However, the applications of AMPs are currently limited owing to their hemolytic activity, poor bioavailability, degradation from proteolytic enzymes, and high-cost production. To overcome these limitations, nanotechnology has been used …

The Antimicrobial Peptide Database Is 20 Years Old: Recent Developments And Future Directions, Guangshun Wang

Journal Articles: Pathology and Microbiology

In 2023, the Antimicrobial Peptide Database (currently available at https://aps.unmc.edu) is 20-years-old. The timeline for the APD expansion in peptide entries, classification methods, search functions, post-translational modifications, binding targets, and mechanisms of action of antimicrobial peptides (AMPs) has been summarized in our previous Protein Science paper. This article highlights new database additions and findings. To facilitate antimicrobial development to combat drug-resistant pathogens, the APD has been re-annotating the data for antibacterial activity (active, inactive, and uncertain), toxicity (hemolytic and nonhemolytic AMPs), and salt tolerance (salt sensitive and insensitive). Comparison of the respective desired and undesired AMP groups produces new knowledge …

An Intravenous Pancreatic Cancer Therapeutic: Characterization Of Crispr/Cas9n-Modified Clostridium Novyi-Non Toxic, Kaitlin M. Dailey, James M. Small, Jessica E. Pullan, Seth Winfree, Krysten E. Vance, Megan Orr, Sanku Mallik, Kenneth W. Bayles, Michael A. Hollingsworth, Amanda E Brooks

Journal Articles: Pathology and Microbiology

Clostridium novyi has demonstrated selective efficacy against solid tumors largely due to the microenvironment contained within dense tumor cores. The core of a solid tumor is typically hypoxic, acidic, and necrotic-impeding the penetration of current therapeutics. C. novyi is attracted to the tumor microenvironment and once there, can both lyse and proliferate while simultaneously re-activating the suppressed immune system. C. novyi systemic toxicity is easily mitigated by knocking out the phage DNA plasmid encoded alpha toxin resulting in C. novyi-NT; but, after intravenous injection spores are quickly cleared by phagocytosis before accomplishing significant tumor localization. C. novyi-NT could be designed …

Androgen Receptor Inhibition Suppresses Anti-Tumor Neutrophil Response Against Bone Metastatic Prostate Cancer Via Regulation Of Tβri Expression, Massar Alsamraae, Diane Costanzo-Garvey, Benjamin A. Teply, Shawna Boyle, Gary Sommerville, Zachary T. Herbert, Colm Morrissey, Alicia J. Dafferner, Maher Y. Abdalla, Rachel W. Fallet, Tammy Kielian, Heather Jensen Smith, Edson I. Deoliveira, Keqiang Chen, Ian A. Bettencourt, Ji Ming Wang, Daniel W. Mcvicar, Tyler Keeley, Fang Yu, Leah M. Cook

Journal Articles: Pathology and Microbiology

Bone metastatic disease of prostate cancer (PCa) is incurable and progression in bone is largely dictated by tumor-stromal interactions in the bone microenvironment. We showed previously that bone neutrophils initially inhibit bone metastatic PCa growth yet metastatic PCa becomes resistant to neutrophil response. Further, neutrophils isolated from tumor-bone lost their ability to suppress tumor growth through unknown mechanisms. With this study, our goal was to define the impact of metastatic PCa on neutrophil function throughout tumor progression and to determine the potential of neutrophils as predictive biomarkers of metastatic disease. Using patient peripheral blood polymorphonuclear neutrophils (PMNs), we identified that …

Investigating Novel Ispe Inhibitors Of The Mep Pathway In Mycobacterium, Seoung Ryoung Choi, Prabagaran Narayanasamy

Journal Articles: Pathology and Microbiology

In a recent effort to mitigate harm from human pathogens, many biosynthetic pathways have been extensively evaluated for their ability to inhibit pathogen growth and to determine drug targets. One of the important products/targets of such pathways is isopentenyl diphosphate. Isopentenyl diphosphate is the universal precursor of isoprenoids, which are essential for the normal functioning of microorganisms. In general, two biosynthetic pathways lead to the formation of isopentenyl diphosphate: (1) the mevalonate pathway in animals; and (2) the non-mevalonate or methylerythritol phosphate (MEP) in many bacteria, and some protozoa and plants. Because the MEP pathway is not found in mammalian …

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

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

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

A Single Dose Of The Deactivated Rabies-Virus Vectored Covid-19 Vaccine, Coravax, Is Highly Efficacious And Alleviates Lung Inflammation In The Hamster Model, Drishya Kurup, Christoph Wirblich, Leila Zabihi Diba, Rachael Lambert, Megan Watson, Noor Shaikh, Holly Ramage, Charalambos Solomides, Matthias J Schnell

Department of Microbiology and Immunology Faculty Papers

Without sufficient herd immunity through either vaccination or natural infection, the coronavirus disease 2019 pandemic is unlikely to be controlled. Waning immunity with the currently approved vaccines suggests the need to evaluate vaccines causing the induction of long-term responses. Here, we report the immunogenicity and efficacy of our adjuvanted single-dose Rabies-vectored SARS-CoV-2 S1 vaccine, CORAVAX, in hamsters. CORAVAX induces high SARS-CoV-2 S1-specific and virus-neutralizing antibodies (VNAs) that prevent weight loss, viral loads, disease, lung inflammation, and the cytokine storm in hamsters. We also observed high Rabies VNA titers. In summary, CORAVAX is a promising dual-antigen vaccine candidate for clinical evaluation …

Realistic And Critical Review Of The State Of Systemic Anti-Microbial Peptides, Guangshun Wang, Abraham F. Mechesso

Journal Articles: Pathology and Microbiology

Antimicrobial peptide research remains active not only because of the growing antibiotic resistance problem but also our desire to understand the role of innate immune peptides in host defense. While numerous peptides are currently under active development for topical use, this article highlights peptides with systemic efficacy. The scaffolds of these peptides range from linear to cyclic forms. The neutropenic mouse model is well established to illustrate antimicrobial efficacy from direct killing. The majority of tests, however, are conducted using normal mice so that both direct antimicrobial and immune regulatory effects can be characterized. These systemic examples underscore the possibility …

Datasets For The Reporting Of Primary Tumour In Bone: Recommendations From The International Collaboration On Cancer Reporting (Iccr), Judith V. M. G. Bovée, Fleur Webster, Fernanda Amary, Daniel Baumhoer, J. L. Hans Bloem, Julia A. Bridge, Justin M. M. Cates, Enrique De Alava, Angelo Paolo Dei Tos, Kevin B. Jones, Annabelle Mahar, G. Petur Nielsen, Alberto Righi, Andrew J. Wagner, Akihiko Yoshida, Christopher D. M. Fletcher

Journal Articles: Pathology and Microbiology

BACKGROUND AND OBJECTIVES: Bone tumours are relatively rare and, as a consequence, treatment in a centre with expertise is required. Current treatment guidelines also recommend review by a specialised pathologist. Here we report on international consensus-based datasets for the pathology reporting of biopsy and resection specimens of bone sarcomas. The datasets were produced under the auspices of the International Collaboration on Cancer Reporting (ICCR), a global alliance of major (inter-)national pathology and cancer organisations.

METHODS AND RESULTS: According to the ICCR's process for dataset development, an international expert panel consisting of pathologists, an oncologic orthopaedic surgeon, a medical oncologist, and …

Improved Database Filtering Technology Enables More Efficient Ab Initio Design Of Potent Peptides Against Ebola Viruses, Thomas Ripperda, Yangsheng Yu, Atul Verma, Elizabeth Klug, Michellie Thurman, St. Patrick Reid, Guangshun Wang

Journal Articles: Pathology and Microbiology

The rapid mutations of viruses such as SARS-CoV-2 require vaccine updates and the development of novel antiviral drugs. This article presents an improved database filtering technology for a more effective design of novel antiviral agents. Different from the previous approach, where the most probable parameters were obtained stepwise from the antimicrobial peptide database, we found it possible to accelerate the design process by deriving multiple parameters in a single step during the peptide amino acid analysis. The resulting peptide DFTavP1 displays the ability to inhibit Ebola virus. A deviation from the most probable peptide parameters reduces antiviral activity. The designed …

Expanding The Landscape Of Amino Acid-Rich Antimicrobial Peptides: Definition, Deployment In Nature, Implications For Peptide Design And Therapeutic Potential, Aaron P. Decker, Abraham F. Mechesso, Guangshun Wang

Journal Articles: Pathology and Microbiology

Unlike the α-helical and β-sheet antimicrobial peptides (AMPs), our knowledge on amino acid-rich AMPs is limited. This article conducts a systematic study of rich AMPs (>25%) from different life kingdoms based on the Antimicrobial Peptide Database (APD) using the program R. Of 3425 peptides, 724 rich AMPs were identified. Rich AMPs are more common in animals and bacteria than in plants. In different animal classes, a unique set of rich AMPs is deployed. While histidine, proline, and arginine-rich AMPs are abundant in mammals, alanine, glycine, and leucine-rich AMPs are common in amphibians. Ten amino acids (Ala, Cys, Gly, His, …

The Staphylococcus Aureus Cida And Lrga Proteins Are Functional Holins Involved In The Transport Of By-Products Of Carbohydrate Metabolism, Jennifer L. Endres, Sujata S. Chaudhari, Xinyan Zhang, Janani Prahlad, Shu-Qi Wang, Lily A. Foley, Sorin Luca, Jeffrey L. Bose, Vinai C. Thomas, Kenneth W. Bayles

Journal Articles: Pathology and Microbiology

The Staphylococcus aureus cidABC and lrgAB operons encode members of a well-conserved family of proteins thought to be involved in programmed cell death (PCD). Based on the structural similarities that CidA and LrgA share with bacteriophage holins, we have hypothesized that these proteins function by forming pores within the cytoplasmic membrane. To test this, we utilized a "lysis cassette" system that demonstrated the abilities of the cidA and lrgA genes to support bacteriophage endolysin-induced cell lysis. Typical of holins, CidA- and LrgA-induced lysis was dependent on the coexpression of endolysin, consistent with the proposed holin-like functions of these proteins. In …

Exploring Epigenetic Reprogramming During Central Nervous System Infection, Zachary Van Roy, Tammy Kielian

Journal Articles: Pathology and Microbiology

Epigenetics involves the study of various modes of adaptable transcriptional regulation, contributing to cell identity, characteristics, and function. During central nervous system (CNS) infection, epigenetic mechanisms can exert pronounced control over the maturation and antimicrobial properties of nearly every immune cell type. Epigenetics is a relatively new field, with the first mention of these marks proposed only a half-century ago and a substantial body of immunological epigenetic research emerging only in the last few decades. Here, we review the best-characterized epigenetic marks and their functions as well as illustrate how various immune cell populations responding to CNS infection utilize these …

Insect Cell Expression And Purification Of Recombinant Sars-Cov-2 Spike Proteins That Demonstrate Ace2 Binding, Lucas R. Struble, Audrey L. Smith, William E. Lutz, Gabrielle Grubbs, Satish Sagar, Kenneth W. Bayles, Prakash Radhakrishnan, Surender Khurana, Dalia El-Gamal, Gloria E. O. Borgstahl

Journal Articles: Pathology and Microbiology

The COVID-19 pandemic caused by SARS-CoV-2 infection has led to socio-economic shutdowns and the loss of over 5 million lives worldwide. There is a need for the identification of therapeutic targets to treat COVID-19. SARS-CoV-2 spike is a target of interest for the development of therapeutic targets. We developed a robust SARS-CoV-2 S spike expression and purification protocol from insect cells and studied four recombinant SARS-CoV-2 spike protein constructs based on the original SARS-CoV-2 sequence using a baculovirus expression system: a spike protein receptor-binding domain that includes the SD1 domain (RBD) coupled to a fluorescent tag (S-RBD-eGFP), spike ectodomain coupled …

Type I Ifn Signaling Protects Mice From Lethal Sars-Cov-2 Neuroinvasion., Md Bashir Uddin, Yuejin Liang, Shengjun Shao, Sunil Palani, Michael Mckelvey, Scott C. Weaver, Keer Sun

Journal Articles: Pathology and Microbiology

Multiple organ damage is common in patients with severe COVID-19, even though the underlying pathogenic mechanisms remain unclear. Acute viral infection typically activates type I IFN (IFN-I) signaling. The antiviral role of IFN-I is well characterized in vitro. However, our understanding of how IFN-I regulates host immune response to SARS-CoV-2 infection in vivo is incomplete. Using a human ACE2-transgenic mouse model, we show in the present study that IFN-I receptor signaling is essential for protection against the acute lethality of SARS-CoV-2 in mice. Interestingly, although IFN-I signaling limits viral replication in the lung, the primary infection site, it is dispensable …

Biofilms: Formation, Research Models, Potential Targets, And Methods For Prevention And Treatment, Yajuan Su, Jaime T. Yrastorza, Mitchell Matis, Jenna Cusick, Siwei Zhao, Guangshun Wang, Jingwei Xie

Journal Articles: Pathology and Microbiology

Due to the continuous rise in biofilm-related infections, biofilms seriously threaten human health. The formation of biofilms makes conventional antibiotics ineffective and dampens immune clearance. Therefore, it is important to understand the mechanisms of biofilm formation and develop novel strategies to treat biofilms more effectively. This review article begins with an introduction to biofilm formation in various clinical scenarios and their corresponding therapy. Established biofilm models used in research are then summarized. The potential targets which may assist in the development of new strategies for combating biofilms are further discussed. The novel technologies developed recently for the prevention and treatment …

Catabolic Ornithine Carbamoyltransferase Activity Facilitates Growth Of Staphylococcus Aureus In Defined Medium Lacking Glucose And Arginine, Itidal Reslane, Cortney R. Halsey, Amanda Stastny, Barbara J. Cabrera, Jong-Sam Ahn, Dhananjay Shinde, Madeline R. Galac, Margaret F. Sladek, Fareha Razvi, Mckenzie K. Lehman, Kenneth W. Bayles, Vinai Chittezham Thomas, Luke D. Handke, Paul D. Fey

Journal Articles: Pathology and Microbiology

Previous studies have found that arginine biosynthesis in Staphylococcus aureus is repressed via carbon catabolite repression (CcpA), and proline is used as a precursor. Unexpectedly, however, robust growth of S. aureus is not observed in complete defined medium lacking both glucose and arginine (CDM-R). Mutants able to grow on agar-containing defined medium lacking arginine (CDM-R) were selected and found to contain mutations within ahrC, encoding the canonical arginine biosynthesis pathway repressor (AhrC), or single nucleotide polymorphisms (SNPs) upstream of the native arginine deiminase (ADI) operon arcA1B1D1C1. Reverse transcription-PCR (RT-PCR) studies found that mutations within ccpA or ahrC or …

Ifn-Γ Transforms The Transcriptomic Landscape And Triggers Myeloid Cell Hyperresponsiveness To Cause Lethal Lung Injury, Atul K. Verma, Michael Mckelvey, Md Bashir Uddin, Sunil Palani, Meng Niu, Christopher Bauer, Shengjun Shao, Keer Sun

Journal Articles: Pathology and Microbiology

Acute Respiratory Distress Syndrome (ARDS) is an inflammatory disease that is associated with high mortality but no specific treatment. Our understanding of initial events that trigger ARDS pathogenesis is limited. We have developed a mouse model of inflammatory lung injury by influenza and methicillin-resistant Staphylococcus aureus (MRSA) coinfection plus daily antibiotic therapy. Using this pneumonic ARDS model, here we show that IFN-γ receptor signaling drives inflammatory cytokine storm and lung tissue damage. By single-cell RNA sequencing (scRNA-seq) analysis, we demonstrate that IFN-γ signaling induces a transcriptional shift in airway immune cells, particularly by upregulating macrophage and monocyte expression of genes …

Ifn-Γ Attenuates Eosinophilic Inflammation But Is Not Essential For Protection Against Rsv-Enhanced Asthmatic Comorbidity In Adult Mice, Abenaya Muralidharan, Md Bashir Uddin, Christopher Bauer, Wenzhe Wu, Xiaoyong Bao, Keer Sun

Journal Articles: Pathology and Microbiology

The susceptibility to respiratory syncytial virus (RSV) infection in early life has been associated with a deficient T-helper cell type 1 (Th1) response. Conversely, healthy adults generally do not exhibit severe illness from RSV infection. In the current study, we investigated whether Th1 cytokine IFN-γ is essential for protection against RSV and RSV-associated comorbidities in adult mice. We found that, distinct from influenza virus, prior RSV infection does not induce significant IFN-γ production and susceptibility to secondary Streptococcus pneumoniae infection in adult wild-type (WT) mice. In ovalbumin (OVA)-induced asthmatic mice, RSV super-infection increases airway neutrophil recruitment and inflammatory lung damage …

Clinical Laboratory Testing Practices In Diffuse Gliomas Prior To Publication Of 2021 World Health Organization Classification Of Central Nervous System Tumors, Shakti H. Ramkissoon, Helen Fernandes, Dolores H. Lopez-Terrada, Meera R. Hameed, Dimitri G. Trembath, Julia A. Bridge, Neal I. Lindeman, Rhona J. Souers, Patricia Vasalos, Daniel J Brat, Joel T. Moncur

Journal Articles: Pathology and Microbiology

CONTEXT.—: Integration of molecular data into glioma classification supports diagnostic, prognostic, and therapeutic decision-making; however, testing practices for these informative biomarkers in clinical laboratories remain unclear.

OBJECTIVE.—: To examine the prevalence of molecular testing for clinically relevant biomarkers in adult and pediatric gliomas through review of a College of American Pathologists proficiency testing survey prior to the release of the 2021 World Health Organization Classification of Central Nervous System Tumors.

DESIGN.—: College of American Pathologists proficiency testing 2020 survey results from 96 laboratories performing molecular testing for diffuse gliomas were used to determine the use of testing for molecular biomarkers …

Accumulation Of Succinyl Coenzyme A Perturbs The Methicillin-Resistant Staphylococcus Aureus (Mrsa) Succinylome And Is Associated With Increased Susceptibility To Beta-Lactam Antibiotics, Christopher Campbell, Claire Fingleton, Merve S. Zeden, Emilio Bueno, Laura A Gallagher, Dhananjay Shinde, Jong-Sam Ahn, Heather M. Olson, Thomas L. Fillmore, Joshua N. Adkins, Fareha Razvi, Kenneth W. Bayles, Paul D. Fey, Vinai Chittezham Thomas, Felipe Cava, Geremy C. Clair, James P. O'Gara

Journal Articles: Pathology and Microbiology

Penicillin binding protein 2a (PBP2a)-dependent resistance to β-lactam antibiotics in methicillin-resistant Staphylococcus aureus (MRSA) is regulated by the activity of the tricarboxylic acid (TCA) cycle via a poorly understood mechanism. We report that mutations in sucC and sucD, but not other TCA cycle enzymes, negatively impact β-lactam resistance without changing PBP2a expression. Increased intracellular levels of succinyl coenzyme A (succinyl-CoA) in the sucC mutant significantly perturbed lysine succinylation in the MRSA proteome. Suppressor mutations in sucA or sucB, responsible for succinyl-CoA biosynthesis, reversed sucC mutant phenotypes. The major autolysin (Atl) was the most succinylated protein in the proteome, …

The Prospect Of Nanoparticle Systems For Modulating Immune Cell Polarization During Central Nervous System Infection, Lee E. Korshoj, Wen Shi, Bin Duan, Tammy Kielian

Journal Articles: Pathology and Microbiology

The blood-brain barrier (BBB) selectively restricts the entry of molecules from peripheral circulation into the central nervous system (CNS) parenchyma. Despite this protective barrier, bacteria and other pathogens can still invade the CNS, often as a consequence of immune deficiencies or complications following neurosurgical procedures. These infections are difficult to treat since many bacteria, such as Staphylococcus aureus, encode a repertoire of virulence factors, can acquire antibiotic resistance, and form biofilm. Additionally, pathogens can leverage virulence factor production to polarize host immune cells towards an anti-inflammatory phenotype, leading to chronic infection. The difficulty of pathogen clearance is magnified by …

Integrative Network Analyses Of Transcriptomics Data Reveal Potential Drug Targets For Acute Radiation Syndrome, Robert Moore, Bhanwar Lal Puniya, Robert Powers, Chittibabu Guda, Kenneth W. Bayles, David B. Berkowitz, Tomáš Helikar

Journal Articles: Pathology and Microbiology

Recent political unrest has highlighted the importance of understanding the short- and long-term effects of gamma-radiation exposure on human health and survivability. In this regard, effective treatment for acute radiation syndrome (ARS) is a necessity in cases of nuclear disasters. Here, we propose 20 therapeutic targets for ARS identified using a systematic approach that integrates gene coexpression networks obtained under radiation treatment in humans and mice, drug databases, disease-gene association, radiation-induced differential gene expression, and literature mining. By selecting gene targets with existing drugs, we identified potential candidates for drug repurposing. Eight of these genes (BRD4, NFKBIA, CDKN1A, TFPI, MMP9, …

Crosstalk Between Staphylococcus Aureus And Innate Immunity: Focus On Immunometabolism, Christopher M. Horn, Tammy Kielian

Journal Articles: Pathology and Microbiology

Staphylococcus aureus is a leading cause of bacterial infections globally in both healthcare and community settings. The success of this bacterium is the product of an expansive repertoire of virulence factors in combination with acquired antibiotic resistance and propensity for biofilm formation. S. aureus leverages these factors to adapt to and subvert the host immune response. With the burgeoning field of immunometabolism, it has become clear that the metabolic program of leukocytes dictates their inflammatory status and overall effectiveness in clearing an infection. The metabolic flexibility of S. aureus offers an inherent means by which the pathogen could manipulate the …

The Evolution And Future Of Targeted Cancer Therapy: From Nanoparticles, Oncolytic Viruses, And Oncolytic Bacteria To The Treatment Of Solid Tumors, Kyle M. Pierce, William R. Miklavcic, Kyle P. Cook, Mikayla Sweitzer Hennen, Kenneth W. Bayles, Michael A. Hollingsworth, Amanda E. Brooks, Jessica E. Pullan, Kaitlin M. Dailey

Journal Articles: Pathology and Microbiology

While many classes of chemotherapeutic agents exist to treat solid tumors, few can generate a lasting response without substantial off-target toxicity despite significant scientific advancements and investments. In this review, the paths of development for nanoparticles, oncolytic viruses, and oncolytic bacteria over the last 20 years of research towards clinical translation and acceptance as novel cancer therapeutics are compared. Novel nanoparticle, oncolytic virus, and oncolytic bacteria therapies all start with a common goal of accomplishing therapeutic drug activity or delivery to a specific site while avoiding off-target effects, with overlapping methodology between all three modalities. Indeed, the degree of overlap …