Immunology of Infectious Disease Commons^™

C-Jun N-Terminal Kinases Regulate Adenovirus-Mediated Autophagy And Antigen Presentation, Sarah R. Klein

Dissertations and Theses (Open Access)

Targeted immunotherapy with recombinant, oncolytic adenoviruses is under investigation for the treatment of cancer. Evidence indicates adenoviruses induce autophagy that is required for oncolysis, but the molecular regulation of autophagy in infected cells remains under investigation. Our data suggested the canonical pathway regulating starvation-induced autophagy was not implemented in adenovirus-induced autophagy; however, adenovirus infection triggered phosphorylation of c-Jun N-terminal kinases (JNK) that was essential for autophagy. Adenoviral replication within the host cell elicited JNK pathway activation leading to B cell lymphoma-2 (Bcl-2) phosphorylation. JNK-dependent Bcl-2 phosphorylation stimulated the dissociation of Bcl-2/beclin 1 heterodimers, enabling beclin 1 to initiate autophagy. Moreover, …

Development Of Novel Antifungal Peptides Based On A Natural Model Of Histatin-5 Peptide, Duy Tu Nguyen

Graduate Theses and Dissertations

Our research group is working toward the development of novel antifungal peptides based on a natural model of peptide histatin-5. Histatin-5 is found in human saliva and known to protect our body against oral infections by Candida species. Candidiasis, or an infection caused by Candida species, is considered one of the most medically important fungal infections worldwide. Blood stream infections caused by Candida species are the fourth leading cause of hospital-acquired fungal infections that is associated with high mortality rates and high costs of treatment. This study investigated the modes of action of histatin-5 with the use of one 16-mer …

Immunoproteomic Analysis Of Proteins Expressed By Two Related Pathogens, Burkholderia Multivorans And Burkholderia Cenocepacia, During Human Infection., Minu Shinoy, Ruth Dennehy, Lorraine Coleman, Stephen Carberru, Kirsten Schaffer, Máire Callaghan, Sean Doyle, Siobhan Mcclean

Articles

Burkholderia cepacia complex (Bcc) is an opportunistic bacterial pathogen that causes chronic infections in people with cystic fibrosis (CF). It is a highly antibiotic resistant organism and Bcc infections are rarely cleared from patients, once they are colonized. The two most clinically relevant species within Bcc are Burkholderia cenocepacia and Burkholderia multivorans. The virulence of these pathogens has not been fully elucidated and the virulence proteins expressed during human infection have not been identified to date. Furthermore, given its antibiotic resistance, prevention of infection with a prophylactic vaccine may represent a better alternative than eradication of an existing infection. We …

Membrane Vesicles Nucleate Mineralo-Organic Nanoparticles And Induce Carbonate Apatite Precipitation In Human Body Fluids, Cheng-Yeu Wu, Jan Martel, Wei-Yun Cheng, Chao-Chih He, David M. Ojcius, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

Recent studies indicate that membrane vesicles (MVs) secreted by various cells are associated with human diseases, including arthritis, atherosclerosis, cancer, and chronic kidney disease. The possibility that MVs may induce the formation of mineralo-organic nanoparticles (NPs) and ectopic calcification has not been investigated so far. Here, we isolated MVs ranging in size between 20 and 400 nm from human serum and FBS using ultracentrifugation and sucrose gradient centrifugation. The MV preparations consisted of phospholipid-bound vesicles containing the serum proteins albumin, fetuin-A, and apolipoprotein A1; the mineralization-associated enzyme alkaline phosphatase; and the exosome proteins TNFR1 and CD63. Notably, we observed that …

Identification Of Leptospira Interrogans Phospholipase C As A Novel Virulence Factor Responsible For Intracellular Free Calcium Ion Elevation During Macrophage Death, Jing-Fang Zhao, Hong-Hu Chen, David M. Ojcius, Xin Zhao, Dexter Sun, Yu-Mei Ge, Lin-Li Zheng, Xu'ai Lin, Lan-Juan Li, Jie Yan

All Dugoni School of Dentistry Faculty Articles

Background: Leptospira-induced macrophage death has been confirmed to play a crucial role in pathogenesis of leptospirosis, a worldwide zoonotic infectious disease. Intracellular free Ca²⁺ concentration ([Ca²⁺]i) elevation induced by infection can cause cell death, but [Ca²⁺]i changes and high [Ca²⁺]i-induced death of macrophages due to infection of Leptospira have not been previously reported.

Methodology/Principal Findings: We first used a Ca²⁺-specific fluorescence probe to confirm that the infection of L. interrogans strain Lai triggered a significant increase of [Ca²⁺]i in mouse J774A.1 or human THP-1 macrophages. Laser confocal microscopic examination …

A Supramolecular Strategy To Assemble Multifunctional Viral Nanoparticles, Limin Chen, Xia Zhao, Yuan Lin, Yubin Huang, Qian Wang

Faculty Publications

Using a one-pot approach driven by the supramolecular interaction between β-cyclodextrin and adamantyl moieties, multifunctional viral nanoparticles can be facilely formulated for biomedical applications.

P2x4 Assembles With P2x7 And Pannexin-1 In Gingival Epithelial Cells And Modulates Reactive Oxygen Species Production And Inflammasome Activation, Shu-Chen Hung, Chul Hee Choi, Najwane Said-Sadier, Larry Johnson, Kalina Rosenova Atanasova, Hanen Sellami, Özlem Yilmaz, David M. Ojcius

All Dugoni School of Dentistry Faculty Articles

We have previously reported that Porphyromonas gingivalis infection of gingival epithelial cells (GEC) requires an exogenous danger signal such as ATP to activate an inflammasome and caspase-1, thereby inducing secretion of interleukin (IL)-1β. Stimulation with extracellular ATP also stimulates production of reactive oxygen species (ROS) in GEC. However, the mechanism by which ROS is generated in response to ATP, and the role that different purinergic receptors may play in inflammasome activation, is still unclear. In this study, we revealed that the purinergic receptor P2X₄ is assembled with the receptor P2X₇ and its associated pore, pannexin-1. ATP induces ROS …

Enrollment In Yfv Vaccine Trial: An Evaluation Of Recruitment Outcomes Associated With A Randomized Controlled Double-Blind Trial Of A Live Attenuated Yellow Fever Vaccine, Paula M. Frew, Eve T. Shapiro, Lu Lu, Srilatha Edupuganti, Harry L. Keyserling, Mark J. Mulligan

Environmental & Global Health Faculty Research

This investigation evaluated several factors associated with diverse participant enrollment of a clinical trial assessing safety, immunogenicity, and comparative viremia associated with administration of 17-D live, attenuated yellow fever vaccine given alone or in combination with human immune globulin. We obtained baseline participant information (e.g., sociodemographic, medical) and followed recruitment outcomes from 2005 to 2007. Of 355 potential Yellow Fever vaccine study participants, 231 cases were analyzed. Strong interest in study participation was observed among racial and ethnically diverse persons with 36.34% eligible following initial study screening, resulting in 18.75% enrollment. The percentage of white participants increased from 63.66% (prescreened …

Hirsutella Sinensis Mycelium Suppresses Interleukin-1b And Interleukin-18 Secretion By Inhibiting Both Canonical And Non-Canonical Inflammasomes, Tsung-Teng Huang, Kowit-Yu Chong, David M. Ojcius, Yi-Hui Wu, Yun-Fei Ko, Cheng-Yeu Wu, Jan Martel, Chia-Chen Lu, Hsin-Chih Lai, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

Cordyceps sinensis is a medicinal mushroom used for centuries in Asian countries as a health supplement and tonic. Hirsutella sinensis—the anamorphic, mycelial form of C. sinensis—possesses similar properties, and is increasingly used as a health supplement. Recently, C. sinensis extracts were shown to inhibit the production of the pro-inflammatory cytokine IL-1β in lipopolysaccharide-treated macrophages. However, the molecular mechanism underlying this process has remained unclear. In addition, whether H. sinensis mycelium (HSM) extracts also inhibit the production of IL-1β has not been investigated. In the present study, the HSM extract suppresses IL-1β and IL-18 secretion, and ATP-induced activation of caspase-1. Notably, …

Neutralizing Antibodies Against The Ricin Toxin Binding Subunit (Rtb), Anastasiya Yermakova

Legacy Theses & Dissertations (2009 - 2024)

Ricin is a toxin that is naturally produced by the seeds of the castor bean plant Ricinus communis, and is part of a family of A-B toxins that includes Shiga, cholera, and anthrax toxins. The toxin consists of two subunits, RTA and RTB, which are linked by a disulfide bond. RTA is an RNA N-glycosidase that selectively targets and inactivates 28S ribosomal RNA, thereby arresting protein synthesis and leading to cell death. RTB is a galactose/ N-acetylgalactosamine-specific lectin that mediates attachment, entry, and intracellular trafficking of ricin in host cells. Currently, there is no approved vaccine or therapeutics available against …

Humoral Immunity To Ehrlichial Infection : Identification And Characterization Of An Igm+ Memory B Cell Population, Jennifer Lynne Yates

Legacy Theses & Dissertations (2009 - 2024)

Immunological memory is a fundamental concept that is key to generating and maintaining immunity to pathogens. Humoral memory resides in part in antigen-specific memory B cells, which are classically defined as class-switched, somatically mutated, long-lived cells that are highly responsive to specific antigen challenge. Despite the focus on class-switched memory B cells, several studies have validated the existence of IgM memory B cells, and have demonstrated distinct functions of IgM and IgG memory B cell subsets. Based on the expression of CD11c, we have identified a large population of IgM memory B cells using a natural model of infection by …

Evidence For The Maturation Of Cellular Immune Responses In Equine Infectious Anemia Virus-Infected Ponies, Chong Liu

Theses and Dissertations--Veterinary Science

Equine infectious anemia virus (EIAV) has been used as a model to investigate protective mechanisms against lentiviruses. Unlike other lentiviruses, EIAV replication can be eventually controlled in most infected horses leading to an inapparent carrier state free of overt clinical signs which can last for many years. Maintenance of this carrier state is absolutely dependent on active immune responses as evidenced by the fact that immunosuppressive drugs can induce the recurrence of disease. However, the immune mechanisms that are responsible for this control of infection are not yet identified. As the resolution of the initial infection is correlated with the …

Equine Serum Antibody Responses To Streptococcus Equi And Streptococcus Zooepidemicus, Rafaela De Negri

Theses and Dissertations--Veterinary Science

Streptococcus zooepidemicus (Sz) and Streptococcus equi (Se) share 98% DNA sequence homology, but display different pathogenic properties. Infection by one organism does not cross-protect against the other. To better understand pathogenic differences between these organisms and gain information about which proteins are expressed in horses infected experimentally with Se, intrauterine Sz or naturally with respiratory Sz we compared antibody specificities of convalescent sera using ELISA. These comparisons were based on sets of 8 and 14 immunoreactive recombinant proteins of Se strain CF32 and Sz strain NC78, respectively. Sera from donkeys that were previously naturally affected with strangles and later developed …

Tumour Inflammasome-Derived Il-1b Recruits Neutrophils And Improves Local Recurrence-Free Survival In Ebv-Induced Nasopharyngeal Carcinoma, Lih-Chyang Chen, Li-Jie Wang, Nang-Ming Tsang, David M. Ojcius, Chia-Chen Chen, Chun-Nan Ouyang, Chuen Hsueh, Ying Liang, Kai-Ping Chang, Chiu-Chin Chen, Yu-Sun Chang

All Dugoni School of Dentistry Faculty Articles

Inflammasomes sense infection and cellular damage and are critical for triggering inflammation through IL-1β production. In carcinogenesis, inflammasomes may have contradictory roles through facilitating antitumour immunity and inducing oncogenic factors. Their function in cancer remains poorly characterized. Here we show that the NLRP3, AIM2 and RIG-I inflammasomes are overexpressed in Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC), and expression levels correlate with patient survival. In tumour cells, AIM2 and RIG-I are required for IL-1β induction by EBV genomic DNA and EBV-encoded small RNAs, respectively, while NLRP3 responds to extracellular ATP and reactive oxygen species. Irradiation and chemotherapy can further activate AIM2 …

Reversible Inhibition Of Chlamydia Trachomatis Infection In Epithelial Cells Due To Stimulation Of P2x4 Receptors, Matthew A. Pettengill, Camila Marques-Da-Silva, Maria Luisa Avila, Verissa W. Lam, Ikechukwu Ollawa, Ali Abdul-Sater, Robson Coutinho-Silva, Georg Hacker, David M. Ojcius, Suellen D'Arc Dos Santos Oliveira

All Dugoni School of Dentistry Faculty Articles

Bacterial infections of the mucosal epithelium are a major cause of human disease. The prolonged presence of microbial pathogens stimulates inflammation of the local tissues, which leads to changes in the molecular composition of the extracellular milieu. A well-characterized molecule that is released to the extracellular milieu by stressed or infected cells is extracellular ATP and its ecto-enzymatic degradation products, which function as signaling molecules through ligation of purinergic receptors. There has been little information, however, on the effects of the extracellular metabolites on bacterial growth in inflamed tissues. Millimolar concentrations of ATP have been previously shown to inhibit irreversibly …

Ivermectin Inhibits Growth Of Chlamydia Trachomatis In Epithelial Cells, Matthew A. Pettengill, Verissa W. Lam, Ikechukwu Ollawa, Camila Marques-Da-Silva, David M. Ojcius

All Dugoni School of Dentistry Faculty Articles

Ivermectin is currently approved for treatment of both clinical and veterinary infections by nematodes, including Onchocerca cervicalis in horses and Onchocerca volvulus in humans. However, ivermectin has never been shown to be effective against bacterial pathogens. Here we show that ivermectin also inhibits infection of epithelial cells by the bacterial pathogen, Chlamydia trachomatis, at doses that could be envisioned clinically for sexually-transmitted or ocular infections by Chlamydia.

Neurosteroid-Mediated Regulation Of Brain Innate Immunity In Hiv/Aids: Dhea-S Suppresses Neurovirulence, Amber Paul, Ferdinand G. Maingat, Maria J. Polyak, Pornpun Vivithanaporn, Farshid Noorbakhsh, Samir Ahboucha, Glen B. Baker, Keir Pearson, Christopher Power

Publications

Neurosteroids are cholesterol-derived molecules synthesized within the brain, which exert trophic and protective actions. Infection by human and feline immunodeficiency viruses (HIV and FIV, respectively) causes neuroinflammation and neurodegeneration, leading to neurological deficits. Secretion of neuroinflammatory host and viral factors by glia and infiltrating leukocytes mediates the principal neuropathogenic mechanisms during, although the effect of neurosteroids on these processes is unknown. We investigated the interactions between neurosteroid mediated effects and lentivirus infection outcomes. Analyses of HIV-infected uninfected human brains disclosed a reduction in neurosteroid synthesis enzyme expression. Human neurons exposed to supernatants from HIV macrophages exhibited suppressed enzyme expression without …

Interactome-Wide Analysis Identifies End-Binding Protein 1 As A Crucial Component For The Speck-Like Particle Formation Of Activated Absence In Melanoma 2 (Aim2) Inflammasomes, Li-Jie Wang, Chia-Wei Hsu, Chiu-Chin Chen, Ying Liang, Lih-Chyang Chen, David M. Ojcius, Ngan-Ming Tsang, Chuen Hsueh, Chih-Ching Wu, Yu-Sun Chang

All Dugoni School of Dentistry Faculty Articles

Inflammasomes are cytoplasmic receptors that can recognize intracellular pathogens or danger signals and are critical for interleukin 1β production. Although several key components of inflammasome activation have been identified, there has not been a systematic analysis of the protein components found in the stimulated complex. In this study, we used the isobaric tags for relative and absolute quantification approach to systemically analyze the interactomes of the NLRP3, AIM2, and RIG-I inflammasomes in nasopharyngeal carcinoma cells treated with specific stimuli of these interactomes (H2O2, poly (dA:dT), and EBV noncoding RNA, respectively). We identified a number of proteins that appeared to be …

Inhibition Of Burkholderia Multivorans Adhesion To Lung Epithelial Cells By Bivalent Lactosides, Ciara Wight, Rosaria Leyden, Paul V. Murphy, Máire Callaghan, Trinidad Velasco-Torrijos, Siobhan Mcclean

Articles

Burkholderia cepacia complex (Bcc) is an opportunistic pathogen in cystic fibrosis patients which is inherently resistant to antimicrobial agents. The mechanisms of attachment and pathogenesis of Bcc, a group of 17 species, are poorly understood. The most commonly identified Bcc species in newly colonised patients, Burkholderia multivorans, continues to be acquired from the environment. Development of therapies which can prevent or reduce the risk of colonization on exposure to Bcc in the environment would be a better alternative to antimicrobial agents. Previously, it has been shown that Bcc strains bound to many glycolipid receptors on lung epithelia. Using a …

Leptospiral Hemolysins Induce Proinflammatory Cytokines Through Toll-Like Receptor 2-And 4-Mediated Jnk And Nf-Κb Signaling Pathways, Huan Wang, Yifei Hu, David M. Ojcius, X. Frank Yang, Chenglin Zhang, Shibiao Ding, Xu'ai Lin, Jie Yan

All Dugoni School of Dentistry Faculty Articles

Infection with pathogenic Leptospira species causes serious systemic inflammation in patients. Although a few leptospiral proinflammatory molecules have been identified, Leptospira likely encodes other unidentified strong inflammation stimulators. The pathogenic L. interrogans genome encodes numerous putative hemolysin genes. Since hemolysins from other bacteria can cause inflammatory reactions, we hypothesized that leptospiral hemolysins may function as proinflammatory stimulators that contribute to the strong inflammation associated with Leptospira infection.