Medical Immunology Commons^™

Inflammation Enhances Il-2 Driven Differentiation Of Cytolytic Cd4 T Cells, Aspen M. Workman, Ashley K. Jacobs, Alexander J. Vogel, Shirley Condon, Deborah M. Brown

Nebraska Center for Virology: Faculty Publications

Cytolytic CD4 T cells (CD4 CTL) have been identified in vivo in response to viral infections; however, the factors necessary for driving the cytolytic phenotype have not been fully elucidated. Our previously published work suggests IL-2 may be the master regulator of perforin-mediated cytotoxicity in CD4 effectors. To further dissect the role of IL-2 in CD4 CTL generation, T cell receptor transgenic mice deficient in the ability to produce IL-2 or the high affinity IL-2 receptor (IL-2Rα, CD25) were used. Increasing concentrations of IL-2 were necessary to drive perforin (Prf) expression and maximal cytotoxicity. Granzyme B (GrB) expression and killing …

Candida Albicans Als5p Amyloid In Host-Microbe Interactions: A Ceanorhabditis Elegans Study, Michael Bois

Dissertations, Theses, and Capstone Projects

Candida albicans, a dimorphic fungus and an opportunistic pathogen, possesses a myriad of adherence factors including members of the agglutinin-like sequence (Als) family of mannoproteins. The adhesin Als5p mediates adhesion to many substrates, and is upregulated during commensal interactions, but is downregulated during active C. albicans infections[1]. An amyloid forming core sequence at residues 325-331 has been shown to be important for Als5p function, because a single amino acid substitution at position 326 (V326N) greatly reduces Als5p-mediated adherence[2]. We evaluated the role of Als5p in host-microbe interactions, using Caenorhabditis elegans as a host model and feeding them Saccharomyces cerevisiae expressing …

An Ethnobotanical, Ecological And Lc-Ms-Based Chemometric Investigation Of Phaleria Nisidai, A Traditional Adaptogen Containing Diterpene Esters From Palau, Micronesia, Daniel Kulakowski

Dissertations, Theses, and Capstone Projects

An ethnobotanical, ecological and LC-MS-based chemometric investigation of Phaleria nisidai, a traditional adaptogen containing diterpene esters from Palau, Micronesia

Palau is a country with a rich heritage of traditional medicine still being practiced. One of the most popular and respected remedies in Palau is a tea made from fresh leaves of Phaleria nisidai Kaneh. (Thymelaeaceae). Interviews conducted to determine the use of this plant revealed that it is employed non-specifically to treat a variety of general health concerns. Its use as a prophylactic to keep away sickness, as a 'system cleaner', as well as for strength and energy indicate …

Quantitative Evaluation Of Microglial Activation And Vascularization In Suicide, Tatiana Pavlovna Schnieder

Dissertations, Theses, and Capstone Projects

Accumulated evidence points to immunological factors in psychiatric disorders. In a variety of chronic neurological disorders, exacerbation is associated with inflammation and a loss of integrity of the blood-brain barrier. Microglia, the principal brain immunological cells in the healthy state, respond to changes in the internal environment of the brain through a sequence of activated states. This study compared microglial phenotypes in the white matter of autopsy brains from 11 suicide victims and 25 subjects who died involuntarily. Both groups included cases with and without major psychiatric disorders, which were determined by PA interviews. Cases were matched for sex, age, …

Suppression Of Aquaporin, A Mediator Of Water Channel Control In The Carcinogenic Liver Fluke, Opisthorchis Viverrini, Sirikanda Thanasuwan, Supawadee Piratae, Paul J. Brindley, Alex Loukas, Sasithorn Kaewkes, Thewarach Laha

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background

Opisthorchiasis and Opisthorchis viverrini-associated bile duct cancer represent major public health threats in Thailand and Laos. The tegument of this food borne fluke plays pivotal roles in parasite metabolism, homeostasis and osmoregulation. Excretory/secretory products also pass from the fluke to the biliary environment, products that likely underlie pathogenesis of liver fluke infection. Aquaporins (AQPs), belong to the major intrinsic protein superfamily of integral plasma membrane channel proteins that selectively transport water across cell membranes. AQPs play key roles as water and ion transport channels through the tegument of helminth parasites.

Methods

Here, two forms of AQP mRNAs from the …

Schistosomes And Snails: A Molecular Encounter, Matty Knight, Halime D. Arican-Goktas, Wannaporn Ittiprasert, Edwin C. Odoemelam, Andre N. Miller, Joanna M. Bridger

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Biomphalaria glabrata snails play an integral role in the transmission of Schistosoma mansoni, the causative agent for human schistosomiasis in the Western hemisphere. For the past two decades, tremendous advances have been made in research aimed at elucidating the molecular basis of the snail/parasite interaction. The growing concern that there is no vaccine to prevent schistosomiasis and only one effective drug in existence provides the impetus to develop new control strategies based on eliminating schistosomes at the snail-stage of the life cycle. To elucidate why a given snail is not always compatible to each and every schistosome it encounters, B. …

Schistosome And Liver Fluke Derived Catechol-Estrogens And Helminth Associated Cancers., José M. Correia Da Costa, Nuno Vale, Maria J. Gouveia, Mónica C. Botelho, Banchob Sripa, Lúcio L. Santos, Júlio H. Santos, Gabriel Rinaldi, Paul J. Brindley

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Infection with helminth parasites remains a persistent public health problem in developing countries. Three of these pathogens, the liver flukes Clonorchis sinensis, Opisthorchis viverrini and the blood fluke Schistosoma haematobium, are of particular concern due to their classification as Group 1 carcinogens: infection with these worms is carcinogenic. Using liquid chromatography-mass spectrometry (LC-MS/MS) approaches, we identified steroid hormone like (e.g., oxysterol-like, catechol estrogen quinone-like, etc.) metabolites and related DNA-adducts, apparently of parasite origin, in developmental stages including eggs of S. haematobium, in urine of people with urogenital schistosomiasis, and in the adult stage of O. viverrini. Since these kinds of …

Helminth.Net: Expansions To Nematode.Net And An Introduction To Trematode.Net, John Martin, Bruce A. Rosa, Philip Ozersky, Kymberlie Hallsworth-Pepin, Xu Zhang, Veena Bhonagiri-Palsikar, Rahul Tyagi, Qi Wang, Young-Jun Choi, Xin Gao, Samantha N. Mcnulty, Paul J. Brindley, Makedonka Mitreva

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Helminth.net (http://www.helminth.net) is the new moniker for a collection of databases: Nematode.net and Trematode.net. Within this collection we provide services and resources for parasitic roundworms (nematodes) and flatworms (trematodes), collectively known as helminths. For over a decade we have provided resources for studying nematodes via our veteran site Nematode.net (http://nematode.net). In this article, (i) we provide an update on the expansions of Nematode.net that hosts omics data from 84 species and provides advanced search tools to the broad scientific community so that data can be mined in a useful and user-friendly manner and (ii) we …

High Prevalence Of Early Childhood Infection By Kshv In A Minority Population In China, Yifei Cao, Veenu Minhas, Xiaohua Tan, Jin Huang, Baodong Wang, Meiyi Zhu, Yuan Gao, Tingting Zhao, Lei Yang, Charles Wood

Nebraska Center for Virology: Faculty Publications

In China, KSHV seroprevalence varies considerably among different regions and ethnicities. But in Xinjiang province, located in the northwestern China, there is a very high seroprevalence of KSHV in adults of Kazak and Ughur ethnicities. However, KSHV prevalence in children and the risk factors associated with the acquisition of infection are currently not known. The aim of this study was to investigate the prevalence of KSHV infection, identify associated socio-economic or behavioral risk factors and the humoral immune response among children in this population. This is a cross-sectional study (N=178) to screen children and their caregivers from Xinjiang for total …

Global Analysis Of Chlorella Variabilis Nc64a Mrna Profiles During The Early Phase Of Paramecium Bursaria Chlorella Virus-1 Infection, Janet M. Rowe, Adrien Jeanniard, James R. Gurnon, Yuannan Xia, David D. Dunigan, James L. Van Etten, Guillaume Blanc

Nebraska Center for Virology: Faculty Publications

The PBCV-1/Chlorella variabilis NC64A system is a model for studies on interactions between viruses and algae. Here we present the first global analyses of algal host transcripts during the early stages of infection, prior to virus replication. During the course of the experiment stretching over 1 hour, about a third of the host genes displayed significant changes in normalized mRNA abundance that either increased or decreased compared to uninfected levels. The population of genes with significant transcriptional changes gradually increased until stabilizing at 40 minutes post infection. Functional categories including cytoplasmic ribosomal proteins, jasmonic acid biosynthesis and anaphase promoting …

Dynamic Attachment Of Chlorovirus Pbcv-1 To Chlorella Variabilis, Irina Agarkova, Brigitte Hertel, Xinzheng Zhang, Les Lane, Alexander Tchourbanov, David D. Dunigan, Gerhard Thiel, Michael G. Rossmann, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

Chloroviruses infect their hosts by specifically binding to and degrading the cell wall of their algal hosts at the site of attachment, using an intrinsic digesting enzyme(s). Chlorovirus PBCV-1 stored as a lysate survived longer than virus alone, suggesting virus attachment to cellular debris may be reversible. Ghost cells (algal cells extracted with methanol) were used as a model to study reversibility of PBCV-1 attachment because ghost cells are as susceptible to attachment and wall digestion as are live cells. Reversibility of attachment to ghost cells was examined by releasing attached virions with a cell wall degrading enzyme extract. The …

Genetic Variation And Possible Mechanisms Driving The Evolution Of Worldwide Fig Mosaic Virus Isolates, Jeewan Jyot Walia, Anouk Willemsen, Eminur Elci, Kadriye Caglayan, Bryce W. Falk, Luis Rubio

Nebraska Center for Virology: Faculty Publications

Fig mosaic virus (FMV) is a multipartite negative-sense RNA virus infecting fig trees worldwide. FMV is transmitted by vegetative propagation and grafting of plant materials, and by the eriophyid mite Aceria ficus. In this work, the genetic variation and evolutionary mechanisms shaping FMV populations were characterized. Nucleotide sequences from four genomic regions (each within the genomic RNAs 1, 2, 3, and 4) from FMV isolates from different countries were determined and analyzed. FMV genetic variation was low, as is seen for many other plant viruses. Phylogenetic analysis showed some geographically distant FMV isolates which clustered together, suggesting long-distance migration. …

Risk Factors For Early Childhood Infection Of Human Herpesvirus-8 In Zambian Children: The Role Of Early Childhood Feeding Practices, Kay L. Crabtree, Janet M. Wojcicki, Veenu Minhas, David R. Smith, Chipepo Kankasa, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

Background—Human herpesvirus-8 (HHV-8) infection in early childhood is common throughout sub-Saharan Africa with prevalence increasing throughout childhood. Specific routes of transmission have not been clearly delineated, though HHV-8 is present in high concentrations in saliva.

Methods—To understand the horizontal transmission of HHV-8 within households to children we enrolled for cross-sectional analysis, 251 households including 254 children, age two and under, in Lusaka, Zambia. For all children, plasma was screened for HHV-8 and HIV-1 and health and behavioral questionnaires were completed. Multi-level logistic regression analysis was conducted to assess independent factors for HHV-8 infection in children.

Results—Risk factors for HHV-8 infection …

Turnip Crinkle Virus Coat Protein Inhibits The Basal Immune Response To Virus Invasion In Arabidopsis By Binding To The Nac Transcription Factor Tip, Teresa Donze, Feng Qu, Paul Twigg, T. Jack Morris

Nebraska Center for Virology: Faculty Publications

Turnip crinkle virus (TCV) has been shown to interact with a NAC transcription factor, TIP, of Arabidopsis thaliana, via its coat protein (CP). This interaction correlates with the resistance response manifested in TCV-resistant Arabidopsis ecotype Di-17. We report that failure of a mutated CP to interact with TIP triggered the corresponding TCV mutant (R6A) to cause more severe symptoms in the TCV-susceptible ecotype Col-0. We hypothesized that TCV regulates antiviral basal immunity through TIP-CP interaction. Consistent with this hypothesis, we found that the rate of accumulation of R6A was measurably slower than wild-type TCV over the course of an …

Cell- And Virus-Mediated Regulation Of The Barrier-To-Autointegration Factor’S Phosphorylation State Controls Its Dna Binding, Dimerization, Subcellular Localization, And Antipoxviral Activity, Augusta Jamin, April Wicklund, Matthew S. Wiebe

Nebraska Center for Virology: Faculty Publications

Barrier-to-autointegration factor (BAF) is a DNA binding protein with multiple cellular functions, including the ability to act as a potent defense against vaccinia virus infection. This antiviral function involves BAF’s ability to condense double-stranded DNA and subsequently prevent viral DNA replication. In recent years, it has become increasingly evident that dynamic phosphorylation involving the vaccinia virus B1 kinase and cellular enzymes is likely a key regulator of multiple BAF functions; however, the precise mechanisms are poorly understood. Here we analyzed how phosphorylation impacts BAF’s DNA binding, subcellular localization, dimerization, and antipoxviral activity through the characterization of BAF phosphomimetic and unphosphorylatable …

Characterization Of A Dual-Tropic Human Immunodeficiency Virus (Hiv-1) Strain Derived From The Prototypical X4 Isolate Hxbc2, Shi-Hua Xiang, Beatriz Pacheco, Dane Bowder, Wen Yuan, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

Human immunodeficiency virus type 1 (HIV-1) coreceptor usage and tropism can be modulated by the V3 loop sequence of the gp120 exterior envelope glycoprotein. For coreceptors, R5 viruses use CCR5, X4 viruses use CXCR4, and dual-tropic (R5X4) viruses use either CCR5 or CXCR4. To understand the requirements for dual tropism, we derived and analyzed a dual-tropic variant of an X4 virus. Changes in the V3 base, which allow gp120 to interact with the tyrosine-sulfated CCR5 N-terminus, and deletion of residues 310/311 in the V3 tip were necessary for efficient CCR5 binding and utilization. Thus, both sets of V3 changes allowed …

Live Siv Vaccine Correlate Of Protection: Immune Complex-Inhibitory Fc Receptor Interactions That Reduce Target Cell Availability, Anthony J. Smith, Stephen W. Wietgrefe, Liang Shang, Cavan S. Reilly, Peter J. Southern, Katherine E. Perkey, Lijie Duan, Heinz Kohler, Sybille Muller, James Robinson, John V. Carlis, Qingsheng Li, R. Paul Johnson, Ashley T. Haase

Nebraska Center for Virology: Faculty Publications

Principles to guide design of an effective vaccine against HIV are greatly needed, particularly to

protect women in the pandemic’s epicentre in Africa. We have been seeking these principles by

identifying correlates of the robust protection associated with SIV_mac239Δnef vaccination in the

SIV-rhesus macaque animal model of HIV-1 transmission to women. We have identified one

correlate of SIV_mac239Δnef protection against vaginal challenge as a resident mucosal system for

SIV-gp41 trimer antibody production and neonatal Fc receptor (FcRn)-mediated concentration of

these antibodies on the path of virus entry to inhibit establishment of infected founder populations

at the …

Review Of Epidemiology And Transmission Of Kaposi’S Sarcoma-Associated Herpesvirus, Veenu Minhas, Charles Wood

Nebraska Center for Virology: Faculty Publications

This review summarizes the current knowledge pertaining to Kaposi sarcoma-associated herpesvirus (KSHV) epidemiology and transmission. Since the identification of KSHV twenty years ago, it is now known to be associated with Kaposi’s sarcoma (KS), primary effusion lymphoma, and multicentric Castleman’s disease. Many studies have been conducted to understand its epidemiology and pathogenesis and their results clearly show that the worldwide distribution of KSHV is uneven. Some geographical areas, such as sub-Saharan Africa, the Mediterranean region and the Xinjiang region of China, are endemic areas, but Western Europe and United States have a low prevalence in the general population. This makes …

Seroprevalence Of Human Herpesvirus 8 And Hepatitis C Virus Among Drug Users In Shanghai, China, Tiejun Zhang, Ying Liu, Yuyan Zhang, Jun Wang, Veenu Minhas, Charles Wood, Na He

Nebraska Center for Virology: Faculty Publications

To elucidate and compare the seroprevalence of human herpesvirus 8 (HHV8) and hepatitis C virus (HCV) among Chinese drug users, a cross-sectional study of 441 participants, was conducted in Shanghai, China, from 2012 through 2013. Seventy-seven (17.5%) participants were found to be positive for HHV8 antibodies, while 271 (61.5%) participants were positive for HCV. No significant association between HHV8 seropositivity and drug use characteristics, sexual behaviors, HCV, or syphilis was observed. In contrast, a statistically significant association between HCV seropositivity and injected drug history (OR, 2.18, 95% CI 1.41–3.37) was detected, whereas no statistically significant association between HCV seropositivity and …

Vaccines Within Vaccines: The Use Of Adenovirus Types 4 And 7 As Influenza Vaccine Vectors, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

adenovirus Types 4 and 7 (ad4 and ad7) are associated with acute respiratory distress (aRD). In order to prevent wide- spread ad-associated aRD (ad-aRD) the United states military immunizes new recruits using a safe and effective lyophi- lized wildtype ad4 and ad7 delivered orally in an enteric-coated capsule. We cloned ad4 and ad7 and modified them to express either a GFP-Luciferase (GFPLuc) fusion gene or a centralized influenza H1 hemagglutinin (Ha1-con). BaLB/c mice were injected with GFPLuc expressing viruses intramuscularly (i.m.) and intranasally (i.n.). ad4 induced significantly higher luciferase expression levels as compared with ad7 by both routes. ad7 transduction …

Comparison Of Two Different Sprint Interval Training Work-To-Rest Ratios On Acute Metabolic And Inflammatory Responses, Christopher R. Harnish

Theses and Dissertations

High intensity exercise is believed to yield greater results on health and human performance than moderate intensity exercise. Extensive research indicates that not only do high-intensity interval training (HIT) and sprint interval training (SIT) produce significant improvements in cardiovascular fitness and disease, they may be more effective at improving long-term metabolic function, including insulin sensitivity (Si), by producing more mitochondria. Moreover, compliance rates for HIT and SIT participation are reported to be the same or better than traditional moderate intensity exercise. Because lack of time is often cited as major hindrance to exercise participation, SIT is also seen as a …

Novel And Predominant Pathogen Responsible For The Enterovirus-Associated Encephalitis In Eastern China, Lei Zhang, Jie Yan, David M. Ojcius, Huakun Lv, Ziping Miao, Yin Chen, Yanjun Zhang, Jvying Yan

All Dugoni School of Dentistry Faculty Articles

Enteroviruses (EV) have been increasingly identified as the causative agent for unknown etiological encephalitis in many parts of the world, but the long period surveillance for enterovirus-associated encephalitis (EAE) was not reported in China. From 2002-2012 in Zhejiang, Coxsackieviruses A9, B1, B2, B3, B4, B5; and echoviruses 3, 4, 6, 9, 14, 25, 30 were detected from the unknown etiological encephalitis cases, with coxsackievirus B4 been identified here for the first time. From 2002-2004 and 2010-2012, echovirus 30 was found to be the periodically predominant serotype for in the EAE. The molecular typing results showed that all the EV isolates …

Septins Of Platyhelminths: Identification, Phylogeny, Expression And Localization Among Developmental Stages Of Schistosoma Mansoni, Ana E. Zeraik, Gabriel Rinaldi, Victoria H. Mann, Anastas Popratiloff, Ana P.U. Araujo, Ricardo Demarco, Paul J. Brindley

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Septins are a family of eukaryotic GTP binding proteins conserved from yeasts to humans. Originally identified in mutants of budding yeast, septins participate in diverse cellular functions including cytokinesis, organization of actin networks, cell polarity, vesicle trafficking and many others. Septins assemble into heteroligomers to form filaments and rings. Here, four septins of Schistosoma mansoni are described, which appear to be conserved within the phylum Platyhelminthes. These orthologues were related to the SEPT5, SEPT10 and SEPT7 septins of humans, and hence we have termed the schistosome septins SmSEPT5, SmSEPT10, SmSEPT7.1 and SmSEPT7.2. Septin transcripts were detected throughout the developmental cycle …

Divergent Antibody Subclass And Specificity Profiles But Not Protective Hla-B Alleles Are Associated With Variable Antibody Effector Function Among Hiv-1 Controllers, Jennifer I. Lai, Anna F. Licht, Anne-Sophie Dugast, Todd Suscovich, Ickwon Choi, Chris Bailey-Kellogg, Galit Alter, Margaret E. Ackerman

Dartmouth Scholarship

Understanding the coordination between humoral and cellular immune responses may be the key to developing protective vaccines, and because genetic studies of long-term HIV-1 nonprogressors have associated specific HLA-B alleles with spontaneous control of viral replication, this subject group presents an opportunity to investigate relationships between arms of the adaptive immune system. Given evidence suggesting that cellular immunity may play a role in viral suppression, we sought to determine whether and how the humoral immune response might vary among controllers. Significantly, Fc-mediated antibody effector functions have likewise been associated with durable viral control. In this study, we compared the effector …

Use Of Irf-3 And/Or Irf-7 Knockout Mice To Study Viral Pathogenesis: Lessons From A Murine Retrovirus-Induced Aids Model, Megan A. O'Connor, William R. Green

Dartmouth Scholarship

Interferon regulatory factor (IRF) regulation of the type I interferon response has not been extensively explored in murine retroviral infections. IRF-3(-/-) and select IRF-3/7(-/-) mice were resistant to LP-BM5-induced pathogenesis. However, further analyses strongly suggested that resistance could be attributed to strain 129-specific contamination of the known retrovirus resistance gene Fv1. Therefore, caution should be taken when interpreting phenotypes observed in these knockout mice, as strain 129-derived genetic polymorphisms may explain observed differences.

A Process Similar To Autophagy Is Associated With Cytocidal Chloroquine Resistance In Plasmodium Falciparum, David Gaviria, Michelle F. Paguio, Lindsey B. Turnbull, Asako Tan, Amila Siriwardana, Debasish Ghosh, Michael T. Ferdig, Anthony P. Sinai, Paul D. Roepe

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Resistance to the cytostatic activity of the antimalarial drug chloroquine (CQ) is becoming well understood, however, resistance to cytocidal effects of CQ is largely unexplored. We find that PfCRT mutations that almost fully recapitulate P. falciparum cytostatic CQ resistance (CQR(CS)) as quantified by CQ IC50 shift, account for only 10-20% of cytocidal CQR (CQR(CC)) as quantified by CQ LD50 shift. Quantitative trait loci (QTL) analysis of the progeny of a chloroquine sensitive (CQS; strain HB3)×chloroquine resistant (CQR; strain Dd2) genetic cross identifies distinct genetic architectures for CQR(CS) vs CQR(CC) phenotypes, including identification of novel interacting chromosomal loci that influence CQ …

Evidence For Finely-Regulated Asynchronous Growth Of Toxoplasma Gondii Cysts Based On Data-Driven Model Selection, Adam M. Sullivan, Xiaopeng Zhao, Yasuhiro Suzuki, Eri Ochiai, Stephen Crutcher, Michael A. Gilchrist

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Toxoplasma gondii establishes a chronic infection by forming cysts preferentially in the brain. This chronic infection is one of the most common parasitic infections in humans and can be reactivated to develop life-threatening toxoplasmic encephalitis in immunocompromised patients. Host-pathogen interactions during the chronic infection include growth of the cysts and their removal by both natural rupture and elimination by the immune system. Analyzing these interactions is important for understanding the pathogenesis of this common infection. We developed a differential equation framework of cyst growth and employed Akaike Information Criteria (AIC) to determine the growth and removal functions that best describe …

Epigenetic Dominance Of Prion Conformers, Eri Saijo, Hae-Eun Kang, Jifeng Bian, Kristi G. Bowling, Shawn Browning, Sehun Kim, Nora Hunter, Glenn C. Telling

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Although they share certain biological properties with nucleic acid based infectious agents, prions, the causative agents of invariably fatal, transmissible neurodegenerative disorders such as bovine spongiform encephalopathy, sheep scrapie, and human Creutzfeldt Jakob disease, propagate by conformational templating of host encoded proteins. Once thought to be unique to these diseases, this mechanism is now recognized as a ubiquitous means of information transfer in biological systems, including other protein misfolding disorders such as those causing Alzheimer's and Parkinson's diseases. To address the poorly understood mechanism by which host prion protein (PrP) primary structures interact with distinct prion conformations to influence pathogenesis, …

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 …