Immunology and Infectious Disease Commons^™

Age-Induced Changes In Anti-Tumor Immunity Alter The Tumor Immune Infiltrate And Impact Response To Immuno-Oncology Treatments, Suzanne I Sitnikova, Jennifer A Walker, Laura B Prickett, Michelle Morrow, Viia E Valge-Archer, Matthew J Robinson, Robert W Wilkinson, Simon J Dovedi

Faculty, Staff and Student Publications

INTRODUCTION: Immuno-oncology (IO) research relies heavily on murine syngeneic tumor models. However, whilst the average age for a cancer diagnosis is 60 years or older, for practical purposes the majority of preclinical studies are conducted in young mice, despite the fact that ageing has been shown to have a significant impact on the immune response.

METHODS: Using aged (60-72 weeks old) mice bearing CT26 tumors, we investigated the impact of ageing on tumor growth as well as the immune composition of the tumor and peripheral lymphoid organs.

RESULTS: We found many differences in the immune cell composition of both the …

Small Molecule Inhibitor Of Tau Self-Association In A Mouse Model Of Tauopathy: A Preventive Study In P301l Tau Jnpl3 Mice, Eliot J Davidowitz, Patricia Lopez, Heidy Jimenez, Leslie Adrien, Peter Davies, James G Moe

Faculty, Staff and Student Publications

Advances in tau biology and the difficulties of amyloid-directed immunotherapeutics have heightened interest in tau as a target for small molecule drug discovery for neurodegenerative diseases. Here, we evaluated OLX-07010, a small molecule inhibitor of tau self-association, for the prevention of tau aggregation. The primary endpoint of the study was statistically significant reduction of insoluble tau aggregates in treated JNPL3 mice compared with Vehicle-control mice. Secondary endpoints were dose-dependent reduction of insoluble tau aggregates, reduction of phosphorylated tau, and reduction of soluble tau. This study was performed in JNPL3 mice, which are representative of inherited forms of 4-repeat tauopathies with …

Loss Of Ubiquitin-Specific Peptidase 18 Destabilizes 14-3-3Ζ Protein And Represses Lung Cancer Metastasis, Zibo Chen, Lin Zheng, Yulong Chen, Xiuxia Liu, Masanori Kawakami, Lisa Maria Mustachio, Jason Roszik, Katherine V Ferry-Galow, Ralph E Parchment, Xin Liu, Thorkell Andresson, Gerard Duncan, Jonathan M Kurie, Jaime Rodriguez-Canales, Xi Liu, Ethan Dmitrovsky

Faculty, Staff and Student Publications

Cancer metastasis is a major cause of cancer-related mortality. Strategies to reduce metastases are needed especially in lung cancer, the most common cause of cancer mortality. We previously reported increased ubiquitin-specific peptidase 18 (USP18) expression in lung and other cancers. Engineered reduction of USP18 expression repressed lung cancer growth and promoted apoptosis. This deubiquitinase (DUB) stabilized targeted proteins by removing the complex interferon-stimulated gene 15 (ISG15). This study explores if the loss of USP18 reduced lung cancer metastasis. USP18 knock-down in lung cancer cells was independently achieved using small hairpin RNAs (shRNAs) and small interfering RNAs (siRNAs). USP18 knock-down reduced …

Tumor-Intrinsic Sirpa Promotes Sensitivity To Checkpoint Inhibition Immunotherapy In Melanoma, Zhicheng Zhou, Mei-Ju May Chen, Yikai Luo, Kamalika Mojumdar, Xin Peng, Hu Chen, Shweta V Kumar, Rehan Akbani, Yiling Lu, Han Liang

Faculty, Staff and Student Publications

Checkpoint inhibition immunotherapy has revolutionized cancer treatment, but many patients show resistance. Here we perform integrative transcriptomic and proteomic analyses on emerging immuno-oncology targets across multiple clinical cohorts of melanoma under anti-PD-1 treatment, on both bulk and single-cell levels. We reveal a surprising role of tumor-intrinsic SIRPA in enhancing antitumor immunity, in contrast to its well-established role as a major inhibitory immune modulator in macrophages. The loss of SIRPA expression is a marker of melanoma dedifferentiation, a key phenotype linked to immunotherapy efficacy. Inhibition of SIRPA in melanoma cells abrogates tumor killing by activated CD8+ T cells in a co-culture …

T Cells Specific For Α-Myosin Drive Immunotherapy-Related Myocarditis, Margaret L Axelrod, Wouter C Meijers, Elles M Screever, Juan Qin, Mary Grace Carroll, Xiaopeng Sun, Elie Tannous, Yueli Zhang, Ayaka Sugiura, Brandie C Taylor, Ann Hanna, Shaoyi Zhang, Kaushik Amancherla, Warren Tai, Jordan J Wright, Spencer C Wei, Susan R Opalenik, Abigail L Toren, Jeffrey C Rathmell, P Brent Ferrell, Elizabeth J Phillips, Simon Mallal, Douglas B Johnson, James P Allison, Javid J Moslehi, Justin M Balko

Faculty, Staff and Student Publications

Immune-related adverse events, particularly severe toxicities such as myocarditis, are major challenges to the utility of immune checkpoint inhibitors (ICIs) in anticancer therapy1. The pathogenesis of ICI-associated myocarditis (ICI-MC) is poorly understood. Pdcd1-/-Ctla4+/- mice recapitulate clinicopathological features of ICI-MC, including myocardial T cell infiltration2. Here, using single-cell RNA and T cell receptor (TCR) sequencing of cardiac immune infiltrates from Pdcd1-/-Ctla4+/- mice, we identify clonal effector CD8+ T cells as the dominant cell population. Treatment with anti-CD8-depleting, but not anti-CD4-depleting, antibodies improved the survival of Pdcd1-/-Ctla4+/- mice. Adoptive transfer of immune cells from mice with myocarditis induced fatal myocarditis in recipients, …

Cisplatin And Gemcitabine Exert Opposite Effects On Immunotherapy With Pd-1 Antibody In K-Ras-Driven Cancer, Christophe Glorieux, Xiaojun Xia, Xin You, Zining Wang, Yi Han, Jing Yang, Gauthier Noppe, Christophe De Meester, Jianhua Ling, Annie Robert, Hui Zhang, Sheng-Ping Li, Huamin Wang, Paul J Chiao, Li Zhang, Xiaobing Li, Peng Huang

Faculty, Staff and Student Publications

INTRODUCTION: Immunochemotherapy using PD-1/PD-L1 antibodies in combination with chemotherapeutic agents has become a mainstream treatment for cancer patients, but it remains unclear which drug combinations would produce best therapeutic outcome.

OBJECTIVES: The purpose of this study was to investigate two common chemotherapeutic drugs, gemcitabine and cisplatin, for their impacts on the therapeutic efficacy of PD-1 antibody in K-ras-driven cancers known to overexpress PD-L1.

METHODS: Both in vitro assays and syngeneic mouse tumor models were used in this study. Biochemical and molecular assays were used to determine the effects of drugs on T cell functions in cell culture models and in …

Targeting De Novo Lipogenesis And The Lands Cycle Induces Ferroptosis In Kras-Mutant Lung Cancer, Caterina Bartolacci, Cristina Andreani, Gonçalo Vale, Stefano Berto, Margherita Melegari, Anna Colleen Crouch, Dodge L Baluya, George Kemble, Kurt Hodges, Jacqueline Starrett, Katerina Politi, Sandra L Starnes, Daniele Lorenzini, Maria Gabriela Raso, Luisa M Solis Soto, Carmen Behrens, Humam Kadara, Boning Gao, Ignacio I Wistuba, John D Minna, Jeffrey G Mcdonald, Pier Paolo Scaglioni

Faculty, Staff and Student Publications

Mutant KRAS (KM), the most common oncogene in lung cancer (LC), regulates fatty acid (FA) metabolism. However, the role of FA in LC tumorigenesis is still not sufficiently characterized. Here, we show that KMLC has a specific lipid profile, with high triacylglycerides and phosphatidylcholines (PC). We demonstrate that FASN, the rate-limiting enzyme in FA synthesis, while being dispensable in EGFR-mutant or wild-type KRAS LC, is required for the viability of KMLC cells. Integrating lipidomic, transcriptomic and functional analyses, we demonstrate that FASN provides saturated and monounsaturated FA to the Lands cycle, the process remodeling oxidized phospholipids, such as PC. Accordingly, …

Reshaping The Tumor Microenvironment With Oncolytic Viruses, Positive Regulation Of The Immune Synapse, And Blockade Of The Immunosuppressive Oncometabolic Circuitry, Teresa T Nguyen, Dong Ho Shin, Sagar Sohoni, Sanjay K Singh, Yisel Rivera-Molina, Hong Jiang, Xuejun Fan, Joy Gumin, Frederick F Lang, Christopher Alvarez-Breckenridge, Filipa Godoy-Vitorino, Lisha Zhu, W Jim Zheng, Lijie Zhai, Erik Ladomersky, Kristen L Lauing, Marta M Alonso, Derek A Wainwright, Candelaria Gomez-Manzano, Juan Fueyo

Faculty, Staff and Student Publications

Background: Oncolytic viruses are considered part of immunotherapy and have shown promise in preclinical experiments and clinical trials. Results from these studies have suggested that tumor microenvironment remodeling is required to achieve an effective response in solid tumors. Here, we assess the extent to which targeting specific mechanisms underlying the immunosuppressive tumor microenvironment optimizes viroimmunotherapy.

Methods: We used RNA-seq analyses to analyze the transcriptome, and validated the results using Q-PCR, flow cytometry, and immunofluorescence. Viral activity was analyzed by replication assays and viral titration. Kyn and Trp metabolite levels were quantified using liquid chromatography-mass spectrometry. Aryl hydrocarbon receptor (AhR) activation …

Redirecting Host Preexisting Influenza A Virus Immunity For Cancer Immunotherapy, Bharat K R Chaganty, Songbo Qiu, Yang Lu, Gabriel Lopez-Berestein, Bulent Ozpolat, Zhen Fan

Faculty, Staff and Student Publications

We tested the concept that host preexisting influenza A virus immunity can be redirected to inhibit tumor growth and metastasis through systemic administration of influenza A virus-related peptides to targeted tumors. Mice infected with influenza A virus strain A/Puerto Rico/8/34 (PR8) were used as a model of a host with preexisting viral immunity. The extent to which preexisting influenza A immunity in PR8-immunized mice can be redirected to inhibit tumor growth and metastasis was first examined by ectopic expression of influenza A nucleoprotein (NP) and hemagglutinin (HA) in syngeneic mammary tumor cells via lentiviral transduction. Then, the feasibility of implementing …

Exploiting 4–1bb Immune Checkpoint To Enhance The Efficacy Of Oncolytic Virotherapy For Diffuse Intrinsic Pontine Gliomas, Virginia Laspidea, Montserrat Puigdelloses, Sara Labiano, Lucía Marrodán, Marc Garcia-Moure, Marta Zalacain, Marisol Gonzalez-Huarriz, Naiara Martínez-Vélez, Iker Ausejo-Mauleon, Daniel De La Nava, Guillermo Herrador-Cañete, Javier Marco-Sanz, Elisabeth Guruceaga, Carlos E De Andrea, María Villalba, Oren Becher, Massimo Squatrito, Verónica Matía, Jaime Gállego Pérez-Larraya, Ana Patiño-García, Sumit Gupta, Candelaria Gomez-Manzano, Juan Fueyo, Marta M Alonso

Faculty, Staff and Student Publications

Diffuse intrinsic pontine gliomas (DIPGs) are aggressive pediatric brain tumors, and patient survival has not changed despite many therapeutic efforts, emphasizing the urgent need for effective treatments. Here, we evaluated the anti-DIPG effect of the oncolytic adenovirus Delta-24-ACT, which was engineered to express the costimulatory ligand 4-1BBL to potentiate the antitumor immune response of the virus. Delta-24-ACT induced the expression of functional 4-1BBL on the membranes of infected DIPG cells, which enhanced the costimulation of CD8+ T lymphocytes. In vivo, Delta-24-ACT treatment of murine DIPG orthotopic tumors significantly improved the survival of treated mice, leading to long-term survivors that developed …

Notch-Induced Mdsc Recruitment After Ohsv Virotherapy In Cns Cancer Models Modulates Antitumor Immunotherapy, Yoshihiro Otani, Ji Young Yoo, Cole T Lewis, Samantha Chao, Jessica Swanner, Toshihiko Shimizu, Jin Muk Kang, Sara A Murphy, Kimberly Rivera-Caraballo, Bangxing Hong, Joseph C Glorioso, Hiroshi Nakashima, Sean E Lawler, Yeshavanth Banasavadi-Siddegowda, John D Heiss, Yuanqing Yan, Guangsheng Pei, Michael A Caligiuri, Zhongming Zhao, E Antonio Chiocca, Jianhua Yu, Balveen Kaur

Faculty, Staff and Student Publications

PURPOSE: Oncolytic herpes simplex virus-1 (oHSV) infection of brain tumors activates NOTCH, however the consequences of NOTCH on oHSV-induced immunotherapy is largely unknown. Here we evaluated the impact of NOTCH blockade on virus-induced immunotherapy.

EXPERIMENTAL DESIGN: RNA sequencing (RNA-seq), TCGA data analysis, flow cytometry, Luminex- and ELISA-based assays, brain tumor animal models, and serum analysis of patients with recurrent glioblastoma (GBM) treated with oHSV was used to evaluate the effect of NOTCH signaling on virus-induced immunotherapy.

RESULTS: TCGA data analysis of patients with grade IV glioma and oHSV treatment of experimental brain tumors in mice showed that NOTCH signaling significantly …

Rickettsial Pathogen Perturbs Tick Circadian Gene To Infect The Vertebrate Host, Supreet Khanal, Vikas Taank, John F. Anderson, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Ixodes scapularis is a medically important tick that transmits several microbes to humans, including rickettsial pathogen Anaplasma phagocytophilum. In nature, these ticks encounter several abiotic factors including changes in temperature, humidity, and light. Many organisms use endogenously generated circadian pathways to encounter abiotic factors. In this study, we provide evidence for the first time to show that A. phagocytophilum modulates the arthropod circadian gene for its transmission to the vertebrate host. We noted a circadian oscillation in the expression of arthropod clock, bmal1, period and timeless genes when ticks or tick cells were exposed to alternate 12 h …

B Cells Are Required To Generate Optimal Anti-Melanoma Immunity In Response To Checkpoint Blockade, Shubhra Singh, Jason Roszik, Neeraj Saini, Vipul Kumar Singh, Karishma Bavisi, Zhiqiang Wang, Long T Vien, Zixi Yang, Suprateek Kundu, Richard E Davis, Laura Bover, Adi Diab, Sattva S Neelapu, Willem W Overwijk, Kunal Rai, Manisha Singh

Faculty, Staff and Student Publications

Immunotherapies such as checkpoint blockade therapies are known to enhance anti-melanoma CD8+ T cell immunity, but only a fraction of patients treated with these therapies achieve durable immune response and disease control. It may be that CD8+ T cells need help from other immune cells to generate effective and long-lasting anti-tumor immunity or that CD8+ T cells alone are insufficient for complete tumor regression and cure. Melanoma contains significant numbers of B cells; however, the role of B cells in anti-melanoma immunity is controversial. In this study, B16 melanoma mouse models were used to determine the role of B cells …

Immunological And Hematological Outcomes Following Protracted Low Dose/Low Dose Rate Ionizing Radiation And Simulated Microgravity, Amber M. Paul, Eliah G. Overbey, Willian A. Da Silveira, Nathaniel Szewczyk, Nina C. Nishiyama, Michael J. Pecaut, Sulekha Anand, Jonathan M. Galazka, Xiao Wen Mao

Publications

Using a ground-based model to simulate spaceflight [21-days of single-housed, hindlimb unloading (HLU) combined with continuous low-dose gamma irradiation (LDR, total dose of 0.04 Gy)], an in-depth survey of the immune and hematological systems of mice at 7-days post-exposure was performed. Collected blood was profiled with a hematology analyzer and spleens were analyzed by whole transcriptome shotgun sequencing (RNA-sequencing). The results revealed negligible differences in immune differentials. However, hematological system analyses of whole blood indicated large disparities in red blood cell differentials and morphology, suggestive of anemia. Murine Reactome networks indicated majority of spleen cells displayed differentially expressed genes (DEG) …

The Effect Of Age On Neurological Inflammation To Acute Sleep Fragmentation In Mice, Molly Taylor

Mahurin Honors College Capstone Experience/Thesis Projects

Obstructive sleep apnea is identified by recurring events of airway collapse during sleep, intermittent hypoxia, and perturbations in sleep continuity, known as sleep fragmentation. There is evidence to suggest that elderly patients are more at risk of developing obstructive sleep apnea. The purpose of this study was to assess whether age affects neurological inflammatory responses to acute sleep fragmentation. This assessment was made by subjecting young (4-5 months old) and old (10-11 months old) male C57BL/6j mice to automated sleep fragmentation, as well as having mice in both age categories as a control with no sleep fragmentation, for twenty-four hours. …

Interleukin-17a Facilitates Chikungunya Virus Infection By Inhibiting Ifn-Α2 Expression, Biswas Neupane, Dhiraj Acharya, Farzana Nazneen, Gabriel Gonzalez-Fernandez, Alex Sutton Flynt, Fengwei Bai

Faculty Publications

Interferons (IFNs) are the key components of innate immunity and are crucial for host defense against viral infections. Here, we report a novel role of interleukin-17A (IL-17A) in inhibiting IFN-α2 expression thus promoting chikungunya virus (CHIKV) infection. CHIKV infected IL-17A deficient (Il17a^−/−) mice expressed a higher level of IFN-α2 and developed diminished viremia and milder footpad swelling in comparison to wild-type (WT) control mice, which was also recapitulated in IL-17A receptor-deficient (Il17ra^−/−) mice. Interestingly, IL-17A selectively blocked IFN-α2 production during CHIKV, but not West Nile virus (WNV) or Zika virus (ZIKV), infections. Recombinant IL-17A …

Tobacco Enhances Bacterial-Induced Periodontal Bone Loss In Mice., Mina Iskander

Electronic Theses and Dissertations

Background: Tobacco smoking is the leading environmental risk factor for periodontal diseases. Delineation of the mechanisms underlying tobacco-induced or exacerbated periodontitis is hampered by the lack of an appropriate and reliable animal model. Hypothesis: We hypothesized that Porphyromonas-gingivalis-infected, cigarette smoke-exposed mice would represent reproducible models of acute (ligature model) and chronic (oral gavage model) tobacco-enhanced periodontitis that reflect multiple aspects of the disease noted in human smokers. Methods: In a chronic oral gavage disease model, Balb/c mice (6-8 weeks, 4 groups of n = 6 per group) were exposed to smoke produced by a Teague-10 smoking machine from 1R6F research …

The Effects Of Heat-Killed Echinostomatid Parasites On Mice Treated With Dextran Sodium Sulfate (Dss), Natalie Gooder

All Graduate Theses, Dissertations, and Other Capstone Projects

Objective: Autoimmune diseases are chronic, incurable, and affect approximately 50 million Americans. This is a strong need for better ways to treat autoimmune diseases. Parasites and parasite proteins have been observed to protect mice from symptoms of induced colitis in mice treated with dextran sodium sulfate (DSS), a model for inflammatory bowel disease (IBD). I hypothesize that non-living echinostomatid parasites, given during DSS treatment, can decrease intestinal inflammation and weight loss, providing a possible novel treatment for IBD.

Methods: A range of DSS concentrations (0.5%-3%) were delivered to female C57BL/6 mice in their drinking water in order to determine the …

Pancreas Of Coxsackievirus-Infected Dams And Their Challenged Pups: A Complex Issue, Sona Sarmirova, Maria Borsanyiova, Brigita Benkoova, Michaela Pospisilova, Rajkumar Rajasekaran, Katarina Berakova, Pavol Gomolcak, Jay Reddy, Shubhada Bopegamage

School of Veterinary and Biomedical Sciences: Faculty Publications

Enteroviral infections are frequent, often asymptomatic in humans and during gravidity. The present study is an extension of our previous investigations where we had shown pancreatitis in challenged pups of CVB4-E2-infected dams. Present investigation describes the effect of gestational infection with this virus on the pancreas of both dams and their challenged pups. Gravid CD1 outbred mice were orally infected with CVB4-E2 virus at different gestation times. Pups were challenged orally with the same virus after 25 days of birth. Organs were collected at selected intervals postinfection (p.i.), and replicating virus and viral-RNA copies were analyzed. Additional readouts included histopathology …

Evaluating The Effects Of Antibody-Conjugated Multi-Walled Carbon Nanotubes In Combination With Microwave Irradiation, Amy Chall

College of Graduate Studies: Theses & Dissertations

Cancer remains one of the largest public health concerns of our day, particularly in developed countries where technological advances have allowed populations to live well into their eighth decade. In America, those in their 80’s have a 1 in 2 chance of developing cancer in their lifetime. Prostate cancer, specifically is the second leading cause of cancer deaths in males. Traditional cancer therapies cause high levels of toxicity to the patient due to mechanisms of action that often attack cancer cells and healthy cells alike. The holy grail of cancer research is to find a treatment that targets the cancer …

Fluorescence-Reported Allelic Exchange Mutagenesis Reveals A Role For Chlamydia Trachomatis Tmea In Invasion That Is Independent Of Host Ahnak, M. J. Mckuen, Konrad E. Mueller, Y. S. Bae, Kenneth A. Fields

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Development of approaches to genetically manipulate Chlamydia is fostering important advances in understanding pathogenesis. Fluorescence-reported allelic exchange mutagenesis (FRAEM) now enables the complete deletion of specific genes in C. trachomatis L2. We have leveraged this technology to delete the coding sequences for a known type III effector. The evidence provided here indicates that CT694/CTL0063 is a virulence protein involved in chlamydial invasion. Based on our findings, we designate the gene product corresponding to ct694-ctl0063 translocated membrane-associated effector A (TmeA). Deletion of tmeA did not impact development of intracellular chlamydiae. However, the absence of TmeA manifested as a decrease in infectivity …

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 …

Nlrp9b Inflammasome Restricts Rotavirus Infection In Intestinal Epithelial Cells, Shu Zhu, Siyuan Ding, Penghua Wang, Zheng Wei, Wen Pan, Noah Palm, Richard Flavell

NYMC Faculty Publications

Rotavirus, a leading cause of severe gastroenteritis and diarrhoea in young children, accounts for around 215,000 deaths annually worldwide. Rotavirus specifically infects the intestinal epithelial cells in the host small intestine and has evolved strategies to antagonize interferon and NF-κB signalling, raising the question as to whether other host factors participate in antiviral responses in intestinal mucosa. The mechanism by which enteric viruses are sensed and restricted in vivo, especially by NOD-like receptor (NLR) inflammasomes, is largely unknown. Here we uncover and mechanistically characterize the NLR Nlrp9b that is specifically expressed in intestinal epithelial cells and restricts rotavirus infection. Our …

A Potent Antimalarial Benzoxaborole Targets A Plasmodium Falciparum Cleavage And Polyadenylation Specificity Factor Homologue., Ebere Sonoiki, Caroline L. Ng, Marcus C. S. Lee, Denghui Guo, Yong-Kang Zhang, Yasheen Zhou, M. R. K. Alley, Vida Ahyong, Laura M. Sanz, Maria Jose Lafuente-Monasterio, Chen Dong, Patrick G. Schupp, Jiri Gut, Jenny Legac, Roland A. Cooper, Francisco-Javier Gamo, Joseph Derisi, Yvonne R. Freund, David A. Fidock, Philip J. Rosenthal

Natural Sciences and Mathematics | Faculty Scholarship

Benzoxaboroles are effective against bacterial, fungal and protozoan pathogens. We report potent activity of the benzoxaborole AN3661 against Plasmodium falciparum laboratory-adapted strains (mean IC50 32 nM), Ugandan field isolates (mean ex vivo IC50 64 nM), and murine P. berghei and P. falciparum infections (day 4 ED90 0.34 and 0.57 mg kg-1, respectively). Multiple P. falciparum lines selected in vitro for resistance to AN3661 harboured point mutations in pfcpsf3, which encodes a homologue of mammalian cleavage and polyadenylation specificity factor subunit 3 (CPSF-73 or CPSF3). CRISPR-Cas9-mediated introduction of pfcpsf3 mutations into parental lines recapitulated AN3661 resistance. PfCPSF3 homology models placed these …

Sphingosine 1-Phosphate Activation Of Egfr As A Novel Target For Meningitic Escherichia Coli Penetration Of The Blood-Brain Barrier, Xiangru Wang, Ravi Maruvada, Andrew J. Morris, Jun O. Liu, Michael J. Wolfgang, Dong Jae Baek, Robert Bittman, Kwang Sik Kim

Internal Medicine Faculty Publications

Central nervous system (CNS) infection continues to be an important cause of mortality and morbidity, necessitating new approaches for investigating its pathogenesis, prevention and therapy. Escherichia coli is the most common Gram-negative bacillary organism causing meningitis, which develops following penetration of the blood–brain barrier (BBB). By chemical library screening, we identified epidermal growth factor receptor (EGFR) as a contributor to E. coli invasion of the BBB in vitro. Here, we obtained the direct evidence that CNS-infecting E. coli exploited sphingosine 1-phosphate (S1P) for EGFR activation in penetration of the BBB in vitro and in vivo. We …

Lipophosphoglycans From Leishmania Amazonensis Strains Display Immunomodulatory Properties Via Tlr4 And Do Not Affect Sand Fly Infection, Paula M. Nogueira, Rafael R. Assis, Ana C. Torrecilhas, Elvira M. Saraiva, Natália L. Pessoa, Marco A. Campos, Eric F. Marialva, Cláudia M. Ríos-Velasquez, Felipe A. Pessoa, Nágila F. Secundino, Jerônimo N. Rugani, Elsa Nieves, Salvatore J. Turco, Maria N. Melo, Rodrigo P. Soares

Molecular and Cellular Biochemistry Faculty Publications

The immunomodulatory properties of lipophosphoglycans (LPG) from New World species of Leishmania have been assessed in Leishmania infantum and Leishmania braziliensis, the causative agents of visceral and cutaneous leishmaniasis, respectively. This glycoconjugate is highly polymorphic among species with variation in sugars that branch off the conserved Gal(β1,4)Man(α1)-PO₄ backbone of repeat units. Here, the immunomodulatory activity of LPGs from Leishmania amazonensis, the causative agent of diffuse cutaneous leishmaniasis, was evaluated in two strains from Brazil. One strain (PH8) was originally isolated from the sand fly and the other (Josefa) was isolated from a human case. The ability of …

Substance P And The Host Immune Response, Megan Elizabeth Foldenauer

Wayne State University Dissertations

This body of work examined the mechanism by which SP regulates host immunity, specifically, its control of growth factors and TLR expression in the P. aeruginosa-infected cornea. The role of mTOR and VIP in corneal infection and inflammation also was tested.

SP has a dual role in bacterial infection, unexpectedly upregulating growth factor production. This was accompanied by macrophage-specific upregulation of pro-inflammatory cytokines, downregulation of anti-inflammatory cytokines, and upregulation of anti-apoptotic genes, as well as a decrease in arginase-producing macrophages (M2 cells), important in stromal healing in these mice. All of these lead to worsened disease, despite the stimulatory effects …

Differential Innate Immune Responses Correlate With The Contrasting Pathogenicity Of The Equine H7n7 Influenza Virus Demonstrated In Horses And Balb/C Mice, Liang Zhang

University of Kentucky Doctoral Dissertations

Equine influenza virus causes a mild, self-limiting upper respiratory disease in its natural host. In stark contrast, equine influenza viruses of the H7N7 subtype produce lethal infection in BALB/c mice. This dissertation explored the mechanism underlying the differential pathogenicity of the equine H7N7 influenza virus observed in horses and BALB/c mice. Initially, a comparative study of the pathogenesis was conducted in BALB/c mice inoculated intranasally with a representative isolate of either H7N7 or H3N8 subtype equine influenza virus. All H3N8 virus-infected mice survived the infection whereas 100% mortality was documented for the mice receiving the H7N7 virus by day 8 …

The Armadillo Repeat Protein Pf16 Is Essential For Flagellar Structure And Function In Plasmodium Male Gametes, Ursula Straschil, Arthur M. Talman, David J. P. Ferguson, Karen A. Bunting, Zhengyao Xu, Elizabeth Bailes, Robert E. Sinden, Anthony A. Holder, Elizabeth F. Smith

Dartmouth Scholarship

Malaria, caused by the apicomplexan parasite Plasmodium, threatens 40% of the world's population. Transmission between vertebrate and insect hosts depends on the sexual stages of the life-cycle. The male gamete of Plasmodium parasite is the only developmental stage that possesses a flagellum. Very little is known about the identity or function of proteins in the parasite's flagellar biology. Here, we characterise a Plasmodium PF16 homologue using reverse genetics in the mouse malaria parasite Plasmodium berghei. PF16 is a conserved Armadillo-repeat protein that regulates flagellar structure and motility in organisms as diverse as green algae and mice. We show that …

Interleukin-10 Mediated Autoregulation Of Murine B-1 B-Cells And Its Role In Borrelia Hermsii Infection, Vishal Sindhava, Michael E Woodman, Brian Stevenson, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

B cells are typically characterized as positive regulators of the immune response, primarily by producing antibodies. However, recent studies indicate that various subsets of B cells can perform regulatory functions mainly through IL-10 secretion. Here we discovered that peritoneal B-1 (B-1P) cells produce high levels of IL-10 upon stimulation with several Toll-like receptor (TLR) ligands. High levels of IL-10 suppressed B-1P cell proliferation and differentiation response to all TLR ligands studied in an autocrine manner in vitro and in vivo. IL-10 that accumulated in cultures inhibited B-1P cells at second and subsequent cell divisions mainly at the G1/S interphase. …