Immunology and Infectious Disease | Open Access Articles

Nucleoside-Diphosphate-Kinase Of P. Gingivalis Is Secreted From Epithelial Cells In The Absence Of A Leader Sequence Through A Pannexin-1 Interactome, Kalina Atanasova, Jungnam Lee, Joann Roberts, Kyulim Lee, David M. Ojcius, Özlem Yilmaz

All Dugoni School of Dentistry Faculty Articles

Nucleoside-diphosphate-kinases (NDKs) are leaderless, multifunctional enzymes. The mode(s) of NDK secretion is currently undefined, while extracellular translocation of bacterial NDKs is critical for avoidance of host pathogen clearance by opportunistic pathogens such as Porphyromonas gingivalis. P. gingivalis-NDK during infection inhibits extracellular-ATP (eATP)/P2X7-receptor mediated cell death in gingival epithelial cells (GECs) via eATP hydrolysis. Furthermore, depletion of pannexin-1-hemichannel (PNX1) coupled with P2X7-receptor blocks the infection-induced eATP release in GECs, and P. gingivalis-NDK impacts this pathway. Ultrastructural and confocal microscopy of P. gingivalis-co-cultured GECs or green-fluorescent-protein (GFP)-P. gingivalis-NDK transfected GECs revealed a perinuclear/cytoplasmic localization of NDK. eATP stimulation induced NDK recruitment to …

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An Iron Detection System Determines Bacterial Swarming Initiation And Biofilm Formation, Chuan-Sheng Lin, Yu-Huan Tsai, Chih-Jung Chang, Shun-Fu Tseng, Tseng-Ru Wu, Chia-Chen Lu, Ting-Shu Wu, Jang-Jih Lu, Jim-Tong Horng, Jan Martel, David M. Ojcius, Hsin-Chih Lai, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

Iron availability affects swarming and biofilm formation in various bacterial species. However, how bacteria sense iron and coordinate swarming and biofilm formation remains unclear. Using Serratia marcescens as a model organism, we identify here a stage-specific iron-regulatory machinery comprising a two-component system (TCS) and the TCS-regulated iron chelator 2-isocyano-6,7-dihydroxycoumarin (ICDH-Coumarin) that directly senses and modulates environmental ferric iron (Fe3+) availability to determine swarming initiation and biofilm formation. We demonstrate that the two-component system RssA-RssB (RssAB) directly senses environmental ferric iron (Fe³⁺) and transcriptionally modulates biosynthesis of flagella and the iron chelator ICDH-Coumarin whose production requires the pvc cluster. …

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Novel Mutation Of Interferon-Γ Receptor 1 Gene Presenting As Early Life Mycobacterial Bronchial Disease, Maria J. Gutierrez, Neelu Kaira, Alexandra Horwitz, Gustavo Nino

Pediatrics Faculty Publications

Mendelian susceptibility to mycobacterial diseases (MSMD) are a spectrum of inherited disorders characterized by localized or disseminated infections caused by atypical mycobacteria. Interferon-γ receptor 1 (IFNGR1) deficiency was the first identified genetic disorder recognized as MSMD. Mutations in the genes encoding IFNGR1 can be recessive or dominant and cause complete or partial receptor deficiency. We present the case of a 2½-year-old boy with a history of recurrent wheezing, diagnosed with endobronchial mycobacterial infection. Immunological workup revealed a homozygous nonsense mutation in the IFNGR1 gene, a novel mutation predicted in silico to cause complete IFNGR1 deficiency. This case demonstrates that ( …

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Pyk2 Activates The Nlrp3 Inflammasome By Directly Phosphorylating Asc And Contributes To Inflammasome-Dependent Peritonitis, I-Che Chung, Chun-Nan Ouyang, Sheng-Ning Yuan, Hsin-Pai P. Li, Jeng-Ting Chen, Hui-Ru Shieh, Yu-Jen Chen, David M. Ojcius, Ching-Liang Chu, Jau-Song Yu, Yu-Sun Chang, Lih-Chyang Chen

All Dugoni School of Dentistry Faculty Articles

The inflammasome adaptor protein, ASC, contributes to both innate immune responses and inflammatory diseases via self-oligomerization, which leads to the activation of the protease, caspase-1. Here, we report that the cytosolic tyrosine kinases, FAK and Pyk2, are differentially involved in NLRP3 and AIM2 inflammasome activation. The inhibition of FAK and Pyk2 with RNA interference or chemical inhibitors dramatically abolished ASC oligomerization, caspase-1 activation, and IL-1β secretion in response to NLRP3 or AIM2 stimulation. Pyk2 is phosphorylated by the kinase Syk and relocalizes to the ASC specks upon NLRP3 inflammasome activation. Pyk2, but not FAK, could directly phosphorylate ASC at Tyr146, …

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Hepatitis C Virus Frameshift/Alternate Reading Frame Protein Suppresses Interferon Responses Mediated By Pattern Recognition Receptor Retinoic-Acid-Inducible Gene-I, Seung Bum Park, Scott Seronello, Wasima Mayer, David M. Ojcius

All Dugoni School of Dentistry Faculty Articles

Hepatitis C virus (HCV) actively evades host interferon (IFN) responses but the mechanisms of how it does so are not completely understood. In this study, we present evidence for an HCV factor that contributes to the suppression of retinoic-acid-inducible gene-I (RIG-I)-mediated IFN induction. Expression of frameshift/alternate reading frame protein (F/ARFP) from HCV -2/+1 frame in Huh7 hepatoma cells suppressed type I IFN responses stimulated by HCV RNA pathogen-associated molecular pattern (PAMP) and poly(IC). The suppression occurred independently of other HCV factors; and activation of interferon stimulated genes, TNFα, IFN-λ1, and IFN-λ2/3 was likewise suppressed by HCV F/ARFP. Point mutations in …

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Characterization Of Nuclear Factor-Kappab Binding Sites In The Freshwater Snail, Biomphalaria Glabrata, Laura E. Deneckere

Lawrence University Honors Projects

Biomphalaria glabrata is an intermediate snail host for the digenean trematode, Schistosoma mansoni, which causes the human disease schistosomiasis. A lot of research has focused on the snail-schistosome interaction, especially in regards to the immune response of the snail. The nuclear factor-kappaB (NF-κB) pathway, which is involved in regulating the immune response, can be triggered by the Toll-like receptor (TLR) signaling pathway. However, not much is known about the specific molecular mechanisms regulating these responses. Both NF-κB and TLR homologues have recently been reported in B. glabrata so it is of great interest to determine if BgNF-κB can regulate …

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Hiv Vaccines: Progress, Limitations And A Crispr/Cas9 Vaccine, Omar A. Garcia Martinez

Biology: Student Scholarship & Creative Works

ABSTRACT: The HIV-1 pandemic continues to thrive due to ineffective HIV-1 vaccines. Historically, the world’s most infectious diseases, such as polio and smallpox, have been eradicated or have come close to eradication due to the advent of effective vaccines. Highly active antiretroviral therapy is able to delay the onset of AIDS but can neither rid the body of HIV-1 proviral DNA nor prevent further transmission. A prophylactic vaccine that prevents the various mechanisms HIV-1 has to evade and attack our immune system is needed to end the HIV-1 pandemic. Recent advances in engineered nuclease systems, like the CRISPR/Cas9 system, have …

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Norovirus Infection And Acquired Immunity In 8 Countries: Results From The Mal-Ed Study, Furqan Kabir, Adil Kalam, Pascal Bessong Pascal Bessong, Zulfiqar Ahmed Bhutta, Anita K. M. Zaidi, (Mal-Ed) Network Investigators, Imran Ahmed, Didar Alam, Syed Asad Ali, Shahida Qureshi, Muneera Rasheed, Sajid Bashir Soofi, Ali Turab, Aisha Khizar Yousafzai

Department of Paediatrics and Child Health

Background: Norovirus is an important cause of childhood diarrhea. We present data from a longitudinal, multicountry study describing norovirus epidemiology during the first 2 years of life.
Methods: A birth cohort of 1457 children across 8 countries contributed 7077 diarrheal stools for norovirus testing. A subset of 199 children contributed additional asymptomatic samples (2307) and diarrheal stools (770), which were used to derive incidence rates and evaluate evidence for acquired immunity.
Results: Across sites, 89% of children experienced at least 1 norovirus infection before 24 months, and 22.7% of all diarrheal stools were norovirus positive. Severity of norovirus-positive diarrhea was …

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Local Admixture Of Amplified And Diversified Secreted Pathogenesis Determinants Shapes Mosaic Toxoplasma Gondii Genomes, Hernan Lorenzi, Asis Khan, Michael S. Behnke, Sivaranjani Namasivayam, Lakshmipuram S. Swapna, Michalis Hadjithomas, Svetlana Karamycheva, Deborah Pinney, Brian P. Brunk, James W. Ajioka, Daniel Ajzenberg, John C. Boothroyd, Jon P. Boyle, Marie L. Dardé, Maria A. Diaz-Miranda, Jitender P. Dubey, Heather M. Fritz, Solange M. Gennari, Brian D. Gregory, Kami Kim, Jeroen P. J. Saeij, Chunlei Su, Michael W. White, Xing-Quan Zhu, Daniel K. Howe, Benjamin M. Rosenthal, Michael E. Grigg, John Parkinson, Liang Liu, Jessica C. Kissinger

Veterinary Science Faculty Publications

Toxoplasma gondii is among the most prevalent parasites worldwide, infecting many wild and domestic animals and causing zoonotic infections in humans. T. gondii differs substantially in its broad distribution from closely related parasites that typically have narrow, specialized host ranges. To elucidate the genetic basis for these differences, we compared the genomes of 62 globally distributed T. gondii isolates to several closely related coccidian parasites. Our findings reveal that tandem amplification and diversification of secretory pathogenesis determinants is the primary feature that distinguishes the closely related genomes of these biologically diverse parasites. We further show that the unusual population structure …

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Genetic And Genomic Basis Of Antibody Response To Porcine Reproductive And Respiratory Syndrome (Prrs) In Gilts And Sows, Nick V. Serão, Robert A. Kemp, Benny Mote, Philip Willson, John C.S. Harding, Stephen C. Bishop, Graham S. Plastow, Jack C.M. Dekkers

Department of Animal Science: Faculty Publications

Background: Our recent research showed that antibody response to porcine reproductive and respiratory syndrome (PRRS), measured as sample-to-positive (S/P) ratio, is highly heritable and has a high genetic correlation with reproductive performance during a PRRS outbreak. Two major quantitative trait loci (QTL) on Sus scrofa chromosome 7 (SSC7; QTL_MHCand QTL₁₃₀) accounted for ~40 % of the genetic variance for S/P. Objectives of this study were to estimate genetic parameters for PRRS S/P in gilts during acclimation, identify regions associated with S/P, and evaluate the accuracy of genomic prediction of S/P across populations with different prevalences of …

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The Differentiation And Protective Function Of Cytolytic Cd4 T Cells In Influenza Infection, Deborah M. Brown, Anna T. Lampe, Aspen M. Workman

School of Biological Sciences: Faculty Publications

CD4 T cells that recognize peptide antigen in the context of class II MHC can differentiate into various subsets that are characterized by their helper functions. However, increasing evidence indicates that CD4 cells with direct cytolytic activity (CD4 CTL) play a role in chronic as well as acute infections, such as influenza A virus (IAV) infection. In the last couple of decades, techniques to measure the frequency and activity of these cytolytic cells has demonstrated their abundance in infections, such as human immunodeficiency virus, mouse pox, murine gamma herpes virus, cytomegalovirus, Epstein–Barr virus, and influenza among others. We now appreciate …

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Full-Text Articles in Immunology and Infectious Disease

Nucleoside-Diphosphate-Kinase Of P. Gingivalis Is Secreted From Epithelial Cells In The Absence Of A Leader Sequence Through A Pannexin-1 Interactome, Kalina Atanasova, Jungnam Lee, Joann Roberts, Kyulim Lee, David M. Ojcius, Özlem Yilmaz

All Dugoni School of Dentistry Faculty Articles

An Iron Detection System Determines Bacterial Swarming Initiation And Biofilm Formation, Chuan-Sheng Lin, Yu-Huan Tsai, Chih-Jung Chang, Shun-Fu Tseng, Tseng-Ru Wu, Chia-Chen Lu, Ting-Shu Wu, Jang-Jih Lu, Jim-Tong Horng, Jan Martel, David M. Ojcius, Hsin-Chih Lai, John Ding-E. Young

All Dugoni School of Dentistry Faculty Articles

Novel Mutation Of Interferon-Γ Receptor 1 Gene Presenting As Early Life Mycobacterial Bronchial Disease, Maria J. Gutierrez, Neelu Kaira, Alexandra Horwitz, Gustavo Nino

Pediatrics Faculty Publications

All Dugoni School of Dentistry Faculty Articles

Hepatitis C Virus Frameshift/Alternate Reading Frame Protein Suppresses Interferon Responses Mediated By Pattern Recognition Receptor Retinoic-Acid-Inducible Gene-I, Seung Bum Park, Scott Seronello, Wasima Mayer, David M. Ojcius

All Dugoni School of Dentistry Faculty Articles

Characterization Of Nuclear Factor-Kappab Binding Sites In The Freshwater Snail, Biomphalaria Glabrata, Laura E. Deneckere

Lawrence University Honors Projects

Hiv Vaccines: Progress, Limitations And A Crispr/Cas9 Vaccine, Omar A. Garcia Martinez

Biology: Student Scholarship & Creative Works

Department of Paediatrics and Child Health

Veterinary Science Faculty Publications

Genetic And Genomic Basis Of Antibody Response To Porcine Reproductive And Respiratory Syndrome (Prrs) In Gilts And Sows, Nick V. Serão, Robert A. Kemp, Benny Mote, Philip Willson, John C.S. Harding, Stephen C. Bishop, Graham S. Plastow, Jack C.M. Dekkers

Department of Animal Science: Faculty Publications

The Differentiation And Protective Function Of Cytolytic Cd4 T Cells In Influenza Infection, Deborah M. Brown, Anna T. Lampe, Aspen M. Workman

School of Biological Sciences: Faculty Publications