Medical Microbiology Commons^™

Chlamydia Trachomatis Subverts Alpha-Actinins To Stabilize Its Inclusion, A. Haines, J. Wesolowski, F. Paumet

Department of Microbiology and Immunology Faculty Papers

Chlamydia trachomatis is the leading cause of sexually transmitted bacterial disease and a global health burden. As an obligate intracellular pathogen, Chlamydia has evolved many strategies to manipulate its host and establish its intracellular niche called the inclusion. C. trachomatis reorganizes the host actin cytoskeleton to form scaffolds around the inclusion and reinforce the growing inclusion membrane. To control the kinetics and formation of actin scaffolds, Chlamydia expresses the effector InaC/CT813, which activates the host GTPase RhoA. Here, we have discovered that InaC stabilizes actin scaffolds through the host actin cross-linking proteins α-actinins 1 and 4. We demonstrate that α-actinins …

Excessive Mechanotransduction In Sensory Neurons Causes Joint Contractures, Shang Ma, Adrienne E Dubin, Luis O Romero, Meaghan Loud, Alexandra Salazar, Sarah Chu, Nikola Klier, Sameer Masri, Yunxiao Zhang, Yu Wang, Alex T Chesler, Katherine A Wilkinson, Valeria Vásquez, Kara L Marshall, Ardem Patapoutian

Faculty, Staff and Student Publications

Distal arthrogryposis (DA) is a collection of rare disorders that are characterized by congenital joint contractures. Most DA mutations are in muscle- and joint-related genes, and the anatomical defects originate cell-autonomously within the musculoskeletal system. However, gain-of-function mutations in PIEZO2, a principal mechanosensor in somatosensation, cause DA subtype 5 (DA5) through unknown mechanisms. We show that expression of a gain-of-function PIEZO2 mutation in proprioceptive sensory neurons that mainly innervate muscle spindles and tendons is sufficient to induce DA5-like phenotypes in mice. Overactive PIEZO2 causes anatomical defects through increased activity within the peripheral nervous system during postnatal development. Furthermore, botulinum toxin …

Differential Co-Expression Networks Of The Gut Microbiota Are Associated With Depression And Anxiety Treatment Resistance Among Psychiatric Inpatients, Dominique S Thompson, Chenlian Fu, Tanmay Gandhi, J Christopher Fowler, B Christopher Frueh, Benjamin L Weinstein, Joseph Petrosino, Julia K Hadden, Marianne Carlson, Cristian Coarfa, Alok Madan

Faculty, Staff and Students Publications

BACKGROUND: Comorbid anxiety and depression are common and are associated with greater disease burden than either alone. Our recent efforts have identified an association between gut microbiota dysfunction and severity of anxiety and depression. In this follow-up, we applied Differential Co-Expression Analysis (DiffCoEx) to identify potential gut microbiota biomarker(s) candidates of treatment resistance among psychiatric inpatients.

METHODS: In a sample of convenience, 100 psychiatric inpatients provided clinical data at admission and discharge; fecal samples were collected early during the hospitalization. Whole genome shotgun sequencing methods were used to process samples. DiffCoEx was used to identify clusters of microbial features significantly …

Identification Of Collaborative Cross Mouse Strains Permissive To Salmonella Enterica Serovar Typhi Infection, Kishore Alugupalli, Sudeep Kothari, Matthew P Cravens, Justin A Walker, Darren T Dougharty, Gregory S. Dickinson, Louis A Gatto, Andreas J Bäumler, Tamding Wangdi, Darla R Miller, Fernando Pardo-Manuel De Villena, Linda D Siracusa

Department of Microbiology and Immunology Faculty Papers

Salmonella enterica serovar Typhi is the causative agent of typhoid fever restricted to humans and does not replicate in commonly used inbred mice. Genetic variation in humans is far greater and more complex than that in a single inbred strain of mice. The Collaborative Cross (CC) is a large panel of recombinant inbred strains which has a wider range of genetic diversity than laboratory inbred mouse strains. We found that the CC003/Unc and CC053/Unc strains are permissive to intraperitoneal but not oral route of S. Typhi infection and show histopathological changes characteristic of human typhoid. These CC strains are immunocompetent, …

Technology Meets Tils: Deciphering T Cell Function In The -Omics Era, William H Hudson, Andreas Wieland

Faculty, Staff and Students Publications

T cells are at the centerstage of cancer immunology due to their ability to recognize mutations within tumor cells and directly mediate cancer cell killing. Immunotherapies to rejuvenate exhausted T cell responses have transformed the clinical management of several malignancies. In parallel, the development of novel multidimensional analysis platforms such as single-cell RNA-sequencing and high-dimensional flow cytometry has yielded unprecedented insights into immune cell biology. This convergence has revealed substantial heterogeneity of tumor-infiltrating immune cells, both within single tumors, across tumor types, and among cancer patients. Here, we discuss the opportunities and challenges of studying the complex tumor microenvironment with …

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 …

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 …

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 …

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 …

The Antibacterial And Anti-Inflammatory Properties Of Probiotics Against Methicillin-Resistant Staphylococcus Aureus (Mrsa), Punploy Klawkla

Chulalongkorn University Theses and Dissertations (Chula ETD)

Background: Dysbiosis refers to an imbalance in the types of microorganisms in a person’s natural f lora, associated with several diseases like asthma, type 2 diabetes, and atopic dermatitis (AD). Reports indicate that Staphylococcus aureuscolonizes about 60%-100% of AD skin, causing barrier dysfunction through virulence factors such as superantigens, enzymes, and other proteins. These factors disrupt skin homeostasis by affecting keratinocytes and immune cells. Additionally, dysbiosis in AD skin is marked by a reduction in commensal microbes like Staphylococcus epidermidis and Corynebacterium spp. In recent years, probiotics have been studied in both live bacteria and bacterial lysate forms. Most studies …

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 Development Of Novel Chimeric Antigen Receptor T Cell Targeting B7h3 For Common Solid Cancers, Thananya Inthanachai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Chimeric antigen receptor (CAR-T cells) have shown a prominent success in hematologic malignancies and are being widely investigated to overcome heterogeneity and immune suppressive environment in solid tumors. B7 homolog 3 (B7H3), an overexpressed antigen across multiple cancers with restricted expression on normal tissues, serves as a potential target for CAR T cells therapy. This study, Gene Expression Profiling Interactive Analysis 2 (GEPIA 2) was used to evaluate CD276 gene upregulation and using flow cytometric staining to investigate an expression of B7H3 across various solid tumors. As a potential antigen targeting cancers, novel B7H3 CAR-T cells were developed from new …

The More Severe Adverse Effect Of Alcohol In Fc Gamma Receptor Iib Deficient (Fcgrllb-/-) Lupus Mice Than In Wild-Type Due To The More Profound Responses Against Alcohol-Induced Leaky Gut, Phatcharapon Yiengwattananon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Consuming alcoholic beverages is well-known to have a part in causing inflammation and obstructing the function of the digestive system, and it may lead to leaky intestines. However, the relationship between alcohol consumption and Systemic Lupus Erythematosus (SLE) remains a subject of controversy continued. In general, alcohol can promote intestinal bacterial dysbiosis and also result in endotoxin release by Gram-negative bacteria. This stimulates many immune cells to produce inflammatory cytokines in the gut. This study focuses on the inflammatory response effect of FcgRIIb-/- mice upon loss of FcgRIIb receptors in which alcohol-induced leaky gut can occur. In 8-week-old mice lacking …

Hmgb2 Regulates The Differentiation And Stemness Of Exhausted Cd8+ T Cells During Chronic Viral Infection And Cancer, Emily N. Neubert, Julia M. Derogatis, Sloan A. Lewis, Karla M. Viramontes, Pedro Ortega, Monique L. Henriquez, Rémi Buisson, Ilhem Messaoudi, Roberto Tinoco

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Chronic infections and cancers evade the host immune system through mechanisms that induce T cell exhaustion. The heterogeneity within the exhausted CD8⁺ T cell pool has revealed the importance of stem-like progenitor (Tpex) and terminal (Tex) exhausted T cells, although the mechanisms underlying their development are not fully known. Here we report High Mobility Group Box 2 (HMGB2) protein expression is upregulated and sustained in exhausted CD8⁺ T cells, and HMGB2 expression is critical for their differentiation. Through epigenetic and transcriptional programming, we identify HMGB2 as a cell-intrinsic regulator of the differentiation and maintenance of Tpex cells during …

Combatting Bacterial Infections: The Efficacy Of Poly-Gamma-Glutamic Acid On The Prevention Of Nasopharyngeal Infections Among Individuals With Cleft Lip And Palate, Florence Pun

Scripps Senior Theses

Cleft lip and palate (CLP) is a medical condition where children are born with an unfused lip and palate. While surgery is required to fuse the lip and palate, there are other conditions that children with CLP face after surgeries, such as otitis media (OM), speech impediments, and difficulty breathing. Particularly, OM occurs frequently in individuals with CLP because the tensor veli palatini muscles cannot open the Eustachian tube frequently and ventilate the middle ear properly, even after surgery. This thesis is a research proposal to evaluate whether γ-PGA can be used in nasal washes to safely prevent nasopharyngeal infections …

Campylobacter Vaccination Reduces Diarrheal Disease And Infant Growth Stunting Among Rhesus Macaques, Sara M. Hendrickson, Archana Thomas, Hans-Peter Raué, Kamm Prongay, Andrew J. Haertel, Nicholas S. Rhoades, Jacob F. Slifka, Lina Gao, Benjamin K. Quintel, Ian J. Amanna, Ilhem Messaoudi, Mark K. Slifka

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Campylobacter-associated enteric disease is estimated to be responsible for more than 160 million cases of gastroenteritis each year and is linked to growth stunting of infants living under conditions of poor sanitation and hygiene. Here, we examine naturally occurring Campylobacter-associated diarrhea among rhesus macaques as a model to determine if vaccination could reduce severe diarrheal disease and infant growth stunting. Compared to unvaccinated controls, there are no Campylobacter diarrhea-associated deaths observed among vaccinated infant macaques and all-cause diarrhea-associated infant mortality is decreased by 76% (P = 0.03). By 9 months of age, there is a 1.3 cm increase in dorsal …

Chronic Alcohol Consumption Dysregulates Innate Immune Response To Sars-Cov-2 In The Lung, Sloan A. Lewis, Isaac R. Cinco, Brianna M. Doratt, Madison B. Blanton, Cherise Hoagland, Natali Newman, Michael Davies, Kathleen A. Grant, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Background Alcohol consumption is widespread with over half of the individuals over 18 years of age in the U.S. reporting alcohol use in the last 30 days. Moreover, 9 million Americans engaged in binge or chronic heavy drinking (CHD) in 2019. CHD negatively impacts pathogen clearance and tissue repair, including in the respiratory tract, thereby increasing susceptibility to infection. Although, it has been hypothesized that chronic alcohol consumption negatively impacts COVID-19 outcomes; the interplay between chronic alcohol use and SARS-CoV-2 infection outcomes has yet to be elucidated.

Methods In this study we employed luminex, scRNA sequencing, and flow cytometry to …

Monoclonal Antibody Therapy Of Breastfeeding Patient Infected With Sars-Cov-2: A Case Report, Nicole E. Marshall, Madison B. Blanton, Brianna M. Doratt, Delphine C. Malherbe, Monica Rincon, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Introduction: Although safety data demonstrated the efficacy and effectiveness of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination for all individuals over 6 months of age, including pregnant and breastfeeding individuals, optimal treatment courses for symptomatic pregnant and lactating individuals infected with SARS-CoV-2 remain to be defined. Case Description: A coronavirus disease 2019 (COVID-19)-vaccinated breastfeeding woman received anti-SARS-CoV-2 monoclonal antibody treatment casirivimab–imdevimab 5 days after diagnosis of a symptomatic breakthrough SARS-CoV-2 infection. Results and Conclusions: The patient did not present with obvious defects in innate or adaptive cellular subsets, but compared with controls had minimal maternal antibody response to recommended …

Mild/Asymptomatic Covid-19 In Unvaccinated Pregnant Mothers Impairs Neonatal Immune Responses, Brianna M. Doratt, Suhas Sureshchandra, Heather E. True, Monica Rincon, Nicole E. Marshall, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Maternal SARS-CoV-2 infection triggers placental inflammation and alters cord blood immune cell composition. However, most studies focus on outcomes of severe maternal infection. Therefore, we analyzed cord blood and chorionic villi from newborns of unvaccinated mothers who experienced mild/asymptomatic SARS-CoV-2 infection during pregnancy. We investigated immune cell rewiring using flow cytometry, single-cell RNA sequencing, and functional readouts using ex vivo stimulation with TLR agonists and pathogens. Maternal infection was associated with increased frequency of memory T and B cells and nonclassical monocytes in cord blood. Ex vivo T and B cell responses to stimulation were attenuated, suggesting a tolerogenic state. …

Integrated Single Cell Analysis Shows Chronic Alcohol Drinking Disrupts Monocyte Differentiation In The Bone Marrow, Sloan A. Lewis, Brianna M. Doratt, Qi Qiao, Madison B. Blanton, Kathleen A. Grant, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Chronic heavy alcohol drinking (CHD) rewires monocytes and macrophages toward heightened inflammatory states with compromised antimicrobial defenses that persist after 1-month abstinence. To determine whether these changes are mediated through alterations in the bone marrow niche, we profiled monocytes and hematopoietic stem cell progenitors (HSCPs) from CHD rhesus macaques using a combination of functional assays and single cell genomics. CHD resulted in transcriptional profiles consistent with increased activation and inflammation within bone marrow resident monocytes and macrophages. Furthermore, CHD resulted in transcriptional signatures associated with increased oxidative and cellular stress in HSCP. Differentiation of HSCP in vitro revealed skewing toward …