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Hla Class I Supertype Associations With Clinical Outcome Of Secondary Dengue Virus Infections In Ethnic Thais, Sasijit Vejbaesya, Rungrot Thongpradit, Siripen Kalayanarooj, Komon Luangtrakool, Panpimon Luangtrakool, Robert V. Gibbons, Duangporn Srinak, Somporn Ngammthaworn, Kusuma Apisawes, In-Kyu Yoon, Stephen J. Thomas, Richard G. Jarman, Anon Srikiatkhachorn, Sharone Green, Dasnayanee Chandanayingyong, Sangshin Park, Jennifer Friedman, Alan L. Rothman, Henry A.F. Stephens May 2016

Hla Class I Supertype Associations With Clinical Outcome Of Secondary Dengue Virus Infections In Ethnic Thais, Sasijit Vejbaesya, Rungrot Thongpradit, Siripen Kalayanarooj, Komon Luangtrakool, Panpimon Luangtrakool, Robert V. Gibbons, Duangporn Srinak, Somporn Ngammthaworn, Kusuma Apisawes, In-Kyu Yoon, Stephen J. Thomas, Richard G. Jarman, Anon Srikiatkhachorn, Sharone Green, Dasnayanee Chandanayingyong, Sangshin Park, Jennifer Friedman, Alan L. Rothman, Henry A.F. Stephens

Sharone Green

BACKGROUND: Human leukocyte antigen (HLA) supertypes are groups of functionally related alleles that present structurally similar antigens to the immune system.

OBJECTIVES: To analyze HLA class I supertype associations with clinical outcome in hospitalized Thai children with acute dengue illness.

METHODS: Seven hundred sixty-two patients and population-matched controls recruited predominantly in Bangkok were HLA-A and -B typed. HLA supertype frequencies were compared and tested for significant dengue disease associations using logistic regression analyses. Multivariable models were built by conducting forward stepwise selection procedures.

RESULTS: In the final logistic regression model, the HLA-B44 supertype was protective against dengue hemorrhagic fever (DHF) …


Topical Lipophilic Epigallocatechin-3-Gallate On Herpes Labialis: A Phase Ii Clinical Trial Of Averteax Formula, Man Zhao, Rong Zheng, Jinyan Jiang, Douglas Dickinson, Baiping Fu, Tin-Chun Chu, Lee Lee, Hanna Pearl, Stephen Hsu Sep 2015

Topical Lipophilic Epigallocatechin-3-Gallate On Herpes Labialis: A Phase Ii Clinical Trial Of Averteax Formula, Man Zhao, Rong Zheng, Jinyan Jiang, Douglas Dickinson, Baiping Fu, Tin-Chun Chu, Lee Lee, Hanna Pearl, Stephen Hsu

Tin-Chun Chu, Ph.D.

Objectives The aim of this study was to clinically evaluate a topical proprietary formulation containing lipophilic catechins (AverTeaX) on recurrent herpes labialis. Methods A double blind, placebo-controlled, randomized trial with 40 participants initially in two groups. Results Compared to the vehicle group, AverTeaX applied topically 6-8 times daily resulted in a significant reduction of clinical episode duration (median 4.5 days, range 1-11 days vs. 9 days, range 2-11 days, p=0.003) and shortened blistering/ulceration stages within an episode from a median of 3 (range 0-6) days to 1 (range 0-3) day (p=0.0003). Median quality of life scores based on a multi-question …


Delineation Of Precursors In Murine Spleen That Develop In Contact With Splenic Endothelium To Give Novel Dendritic-Like Cells., Jonathan Tan, Pravin Periasamy, Helen O'Neill Sep 2015

Delineation Of Precursors In Murine Spleen That Develop In Contact With Splenic Endothelium To Give Novel Dendritic-Like Cells., Jonathan Tan, Pravin Periasamy, Helen O'Neill

Jonathan Tan

Hematopoietic cell lineages are best described in terms of distinct progenitors with limited differentiative capacity. To distinguish cell lineages, it is necessary to define progenitors and induce their differentiation in vitro. We previously reported in vitro development of immature dendritic-like cells (DCs) in long-term cultures (LTCs) of murine spleen, and in cocultures of spleen or bone marrow (BM) over splenic endothelial cell lines derived from LTCs. Cells produced are phenotypically distinct CD11b(hi)CD11c(lo)CD8(-)MHC-II(-) cells, tentatively named L-DCs. Here we delineate L-DC progenitors as different from known DC progenitors in BM and DC precursors in spleen. The progenitor is contained within the …


Haematopoietic Stem Cells In Spleen Have Distinct Differentiative Potential For Antigen Presenting Cells., Jonathan Tan, Helen O'Neill Sep 2015

Haematopoietic Stem Cells In Spleen Have Distinct Differentiative Potential For Antigen Presenting Cells., Jonathan Tan, Helen O'Neill

Jonathan Tan

Dendritic cells (DC) are known to develop from macrophage dendritic progenitors (MDP) in bone marrow (BM), which give rise to conventional (c)DC and monocytes, both dominant antigen presenting cell (APC) subsets in spleen. This laboratory has however defined a distinct dendritic-like cell subset in spleen (L-DC), which can also be derived in long-term cultures of spleen. In line with the restricted in vitro development of only L-DC in these stromal cultures, we questioned whether self-renewing HSC or progenitors exist in spleen with restricted differentiative capacity for only L-DC. Neonatal spleen and BM were compared for their ability to reconstitute mice …


Concise Review: Dendritic Cell Development In The Context Of The Spleen Microenvironment, Jonathan Tan, Helen O'Neill Sep 2015

Concise Review: Dendritic Cell Development In The Context Of The Spleen Microenvironment, Jonathan Tan, Helen O'Neill

Jonathan Tan

The dendritic cell (DC) population in spleen comprises a mixture of cells including endogenous DC progenitors, DC precursors migrating in from blood and bone marrow, and DC in different states of differentiation and activation. A role for different microenvironments in supporting the dynamic development of murine DC of different types or lineages is considered here. Recent evidence for production of DC dependent on splenic stromal cells is reviewed in the light of evidence that cell production is dependent on cells comprising an endothelial niche in spleen. The possibility that self-renewing progenitors in spleen give rise to DC with tolerogenic or …


Inhibition Of Sterile Danger Signals, Uric Acid And Atp, Prevents Inflammasome Activation And Protects From Alcoholic Steatohepatitis In Mice., Arvin Iracheta-Vellve, Jan Petrasek, Abhishek Satishchandran, Benedek Gyongyosi, Banishree Saha, Karen Kodys, Katherine Fitzgerald, Evelyn Kurt-Jones, Gyongyi Szabo Aug 2015

Inhibition Of Sterile Danger Signals, Uric Acid And Atp, Prevents Inflammasome Activation And Protects From Alcoholic Steatohepatitis In Mice., Arvin Iracheta-Vellve, Jan Petrasek, Abhishek Satishchandran, Benedek Gyongyosi, Banishree Saha, Karen Kodys, Katherine Fitzgerald, Evelyn Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

Background & Aims: The inflammasome is a well-characterized inducer of inflammation in alcoholic steatohepatitis (ASH). Inflammasome activation requires two signals for mature interleukin (IL)-1β production. Here we asked whether metabolic danger signals trigger inflammasome activation in ASH.

Results:The sterile danger signals, ATP and uric acid, were increased in the serum and liver of alcohol-fed mice. Depletion of uric acid or ATP, or lack of ATP signaling attenuated ASH and prevented inflammasome activation and its major downstream cytokine, IL-1β. Pharmacological depletion of uric acid with allopurinol provided significant protection from alcohol-induced inflammatory response, steatosis and liver damage, and additional protection was …


Metabolic Danger Signals, Uric Acid And Atp, Mediate Inflammatory Cross-Talk Between Hepatocytes And Immune Cells In Alcoholic Liver Disease., Jan Petrasek, Arvin Iracheta-Vellve, Banishree Saha, Abhishek Satishchandran, Karen Kodys, Katherine Fitzgerald, Evelyn Kurt-Jones, Gyongyi Szabo Aug 2015

Metabolic Danger Signals, Uric Acid And Atp, Mediate Inflammatory Cross-Talk Between Hepatocytes And Immune Cells In Alcoholic Liver Disease., Jan Petrasek, Arvin Iracheta-Vellve, Banishree Saha, Abhishek Satishchandran, Karen Kodys, Katherine Fitzgerald, Evelyn Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

Inflammation defines the progression of ALD from reversible to advanced stages. Translocation of bacterial LPS to the liver from the gut is necessary for alcohol-induced liver inflammation. However, it is not known whether endogenous, metabolic danger signals are required for inflammation in ALD. Uric acid and ATP, 2 major proinflammatory danger signals, were evaluated in the serum of human volunteers exposed to a single dose of ethanol or in supernatants of primary human hepatocytes exposed to ethanol. In vitro studies were used to evaluate the role of uric acid and ATP in inflammatory cross-talk between hepatocytes and immune cells. The …


Positive Selection Drives Preferred Segment Combinations During Influenza Virus Reassortment, Konstantin Zeldovich, Ping Liu, Nicholas Renzette, Matthieu Foll, Serena Pham, Sergey Venev, Glen Gallagher, Daniel Bolon, Evelyn Kurt-Jones, Jeffrey Jensen, Daniel Caffrey, Celia Schiffer, Timothy Kowalik, Jennifer Wang, Robert Finberg Jun 2015

Positive Selection Drives Preferred Segment Combinations During Influenza Virus Reassortment, Konstantin Zeldovich, Ping Liu, Nicholas Renzette, Matthieu Foll, Serena Pham, Sergey Venev, Glen Gallagher, Daniel Bolon, Evelyn Kurt-Jones, Jeffrey Jensen, Daniel Caffrey, Celia Schiffer, Timothy Kowalik, Jennifer Wang, Robert Finberg

Celia A. Schiffer

Influenza A virus (IAV) has a segmented genome that allows for the exchange of genome segments between different strains. This reassortment accelerates evolution by breaking linkage, helping IAV cross species barriers to potentially create highly virulent strains. Challenges associated with monitoring the process of reassortment in molecular detail have limited our understanding of its evolutionary implications. We applied a novel deep sequencing approach with quantitative analysis to assess the in vitro temporal evolution of genomic reassortment in IAV. The combination of H1N1 and H3N2 strains reproducibly generated a new H1N2 strain with the hemagglutinin and nucleoprotein segments originating from H1N1 …


Alcohol And Hcv: Implications For Liver Cancer, Gyongyi Szabo, Banishree Saha, Terence Bukong Jun 2015

Alcohol And Hcv: Implications For Liver Cancer, Gyongyi Szabo, Banishree Saha, Terence Bukong

Gyongyi Szabo

Liver cancers are one of the deadliest known malignancies which are increasingly becoming a major public health problem in both developed and developing countries. Overwhelming evidence suggests a strong role of infection with hepatitis B and C virus (HBV and HCV), alcohol abuse, as well as metabolic diseases such as obesity and diabetes either individually or synergistically to cause or exacerbate the development of liver cancers. Although numerous etiologic mechanisms for liver cancer development have been advanced and well characterized, the lack of definite curative treatments means that gaps in knowledge still exist in identifying key molecular mechanisms and pathways …


A Novel Human Radixin Peptide Inhibits Hepatitis C Virus Infection At The Level Of Cell Entry, Terence Bukong, Karen Kodys, Gyongyi Szabo Jun 2015

A Novel Human Radixin Peptide Inhibits Hepatitis C Virus Infection At The Level Of Cell Entry, Terence Bukong, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

Hepatitis C virus infection of hepatocytes is a multistep process involving the interaction between viral and host cell molecules. Recently, we identified ezrin-moesin-radixin proteins and spleen tyrosine kinase (SYK) as important host therapeutic targets for HCV treatment development. Previously, an ezrin hinge region peptide (Hep1) has been shown to exert anti-HCV properties in vivo, though its mechanism of action remains limited. In search of potential novel inhibitors of HCV infection and their functional mechanism we analyzed the anti-HCV properties of different human derived radixin peptides. Sixteen different radixin peptides were derived, synthesized and tested. Real-time quantitative PCR, cell toxicity assay, …


The Genetics Of Hepatitis C Virus Underlie Its Ability To Escape Humoral Immunity, Jay Kolls, Gyongyi Szabo Jun 2015

The Genetics Of Hepatitis C Virus Underlie Its Ability To Escape Humoral Immunity, Jay Kolls, Gyongyi Szabo

Gyongyi Szabo

Hepatitis C virus (HCV) is a leading cause of chronic liver disease, and efforts to develop therapeutic vaccine strategies have been limited by immune escape due to HCV variants that are resistant to current vaccines or HCV variants that rapidly acquire new resistance-conferring mutations. Recently, the crystal structure of the viral envelope protein E2 region was resolved as well as how E2 docks to the host CD81 protein; therefore, antibodies that block this interaction should prevent viral entry into host cells. In this issue of the JCI, Bailey and colleagues show that immune escape of HCV can occur by naturally …


Antiviral Activity Of Theaflavin Digallate Against Herpes Simplex Virus Type 1, Aline De Oliveira, Derek Prince, Chih-Yu Lo, Lee Lee, Tin-Chun Chu May 2015

Antiviral Activity Of Theaflavin Digallate Against Herpes Simplex Virus Type 1, Aline De Oliveira, Derek Prince, Chih-Yu Lo, Lee Lee, Tin-Chun Chu

Tin-Chun Chu, Ph.D.

Tea is the second most consumed drink in the world. The beneficial effects of tea have been mostly attributed to its catechin content. Black tea is derived from the leaves of Camellia sinensis plant, and it is rich in theaflavin polyphenols, in particular theaflavin (TF1), theaflavin-3-monogallate (TF2A), theaflavin-3′-monogallate (TF2B), and theaflavin-3,3′-digallate (TF3). Vero and A549 cells were used to evaluate the effect of purified individual black tea theaflavins as anti-herpes simplex virus 1 agents. With the rise of HSV resistant strains, there is a critical need to develop novel antiherpesviral treatments. Results of the cytotoxicity assay tested by MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxy-phenyl)-2-(4-sulfophenyl)-2H-tetrazolium] …


Alcohol-Induced Mir-27a Regulates Differentiation And M2 Macrophage Polarization Of Normal Human Monocytes, Banishree Saha, Johanna Bruneau, Karen Kodys, Gyongyi Szabo May 2015

Alcohol-Induced Mir-27a Regulates Differentiation And M2 Macrophage Polarization Of Normal Human Monocytes, Banishree Saha, Johanna Bruneau, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

Alcohol abuse is a leading cause of liver disease characterized by liver inflammation, fatty liver, alcoholic hepatitis, or liver cirrhosis. Immunomodulatory effects of alcohol on monocytes and macrophages contribute to alcoholic liver disease. Alcohol use, an independent risk factor for progression of hepatitis C virus (HCV) infection-mediated liver disease, impairs host defense and alters cytokine production and monocyte/macrophage activation. We hypothesized that alcohol and HCV have synergistic effects on the phenotype and function of monocytes. Our data show that acute alcohol binge drinking in healthy volunteers results in increased frequency of CD16(+) and CD68(+) and M2-type (CD206(+), dendritic cell [DC]-SIGN(+)-expressing …


Influenza Virus Drug Resistance: A Time-Sampled Population Genetics Perspective, Matthieu Foll, Yu Poh, Nicholas Renzette, Anna Admetlla, Claudia Bank, Hyunjin Shim, Anna Malaspinas, Gregory Ewing, Ping Liu, Daniel Wegmann, Daniel Caffrey, Konstantin Zeldovich, Daniel Bolon, Jennifer Wang, Timothy Kowalik, Celia Schiffer, Robert Finberg, Jeffrey Jensen Jan 2015

Influenza Virus Drug Resistance: A Time-Sampled Population Genetics Perspective, Matthieu Foll, Yu Poh, Nicholas Renzette, Anna Admetlla, Claudia Bank, Hyunjin Shim, Anna Malaspinas, Gregory Ewing, Ping Liu, Daniel Wegmann, Daniel Caffrey, Konstantin Zeldovich, Daniel Bolon, Jennifer Wang, Timothy Kowalik, Celia Schiffer, Robert Finberg, Jeffrey Jensen

Celia A. Schiffer

The challenge of distinguishing genetic drift from selection remains a central focus of population genetics. Time-sampled data may provide a powerful tool for distinguishing these processes, and we here propose approximate Bayesian, maximum likelihood, and analytical methods for the inference of demography and selection from time course data. Utilizing these novel statistical and computational tools, we evaluate whole-genome datasets of an influenza A H1N1 strain in the presence and absence of oseltamivir (an inhibitor of neuraminidase) collected at thirteen time points. Results reveal a striking consistency amongst the three estimation procedures developed, showing strongly increased selection pressure in the presence …


Hiv-1 Protease-Substrate Coevolution In Nelfinavir Resistance, Madhavi Kolli, Aysegul Ozen, Nese Yilmaz, Celia Schiffer Jan 2015

Hiv-1 Protease-Substrate Coevolution In Nelfinavir Resistance, Madhavi Kolli, Aysegul Ozen, Nese Yilmaz, Celia Schiffer

Celia A. Schiffer

Resistance to various human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs) challenges the effectiveness of therapies in treating HIV-1-infected individuals and AIDS patients. The virus accumulates mutations within the protease (PR) that render the PIs less potent. Occasionally, Gag sequences also coevolve with mutations at PR cleavage sites contributing to drug resistance. In this study, we investigated the structural basis of coevolution of the p1-p6 cleavage site with the nelfinavir (NFV) resistance D30N/N88D protease mutations by determining crystal structures of wild-type and NFV-resistant HIV-1 protease in complex with p1-p6 substrate peptide variants with L449F and/or S451N. Alterations of residue …


Another Armed Cd4(+) T Cell Ready To Battle Hepatocellular Carcinoma, Roniel Cabrera, Gyongyi Szabo Sep 2014

Another Armed Cd4(+) T Cell Ready To Battle Hepatocellular Carcinoma, Roniel Cabrera, Gyongyi Szabo

Gyongyi Szabo

No abstract provided.


Human Ezrin-Moesin-Radixin Proteins Modulate Hepatitis C Virus Infection, Terence Bukong, Karen Kodys, Gyongyi Szabo Sep 2014

Human Ezrin-Moesin-Radixin Proteins Modulate Hepatitis C Virus Infection, Terence Bukong, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

Host cytoskeletal proteins of the ezrin-moesin-radixin (EMR) family have been shown to modulate single-stranded RNA virus infection through regulating stable microtubule formation. Antibody engagement of CD81, a key receptor for hepatitis C virus (HCV) entry, induces ezrin phosphorylation. Here we tested the role of EMR proteins in regulating HCV infection and explored potential therapeutic targets. We show that HCV E2 protein induces rapid ezrin phosphorylation and its cellular redistribution with F-actin by way of spleen tyrosine kinase (SYK). Therapeutically blocking the functional roles of SYK or F-actin reorganization significantly reduced Huh7.5 cell susceptibility to HCV J6/JFH-1 infection. Using gene regulation, …


Differences In Innate Immune Signaling Between Alcoholic And Non-Alcoholic Steatohepatitis, Jan Petrasek, Timea Csak, Michal Ganz, Gyongyi Szabo Sep 2014

Differences In Innate Immune Signaling Between Alcoholic And Non-Alcoholic Steatohepatitis, Jan Petrasek, Timea Csak, Michal Ganz, Gyongyi Szabo

Gyongyi Szabo

The similar histopathological characteristics of alcoholic steatohepatitis (ASH) and non-alcoholic steatohepatitis (NASH), and the crucial role of the innate immune response in both conditions may lead to the assumption that ASH and NASH represent the same pathophysiological entities caused by different risk factors. In this review paper, we elaborate on the pathophysiological differences between these two entities and highlight the disease-specific involvement of signaling molecules downstream of the Toll-like receptor 4, and the differential mechanism by which the inflammasome contributes to ASH versus NASH. Our findings emphasize that ASH and NASH have disease-specific mechanisms and therefore represent distinct biological entities. …


Micro-Rna-155 Deficiency Prevents Alcohol-Induced Serum Endotoxin Increase And Small Bowel Inflammation In Mice, Dora Lippai, Shashi Bala, Donna Catalano, Karen Kodys, Gyongyi Szabo Sep 2014

Micro-Rna-155 Deficiency Prevents Alcohol-Induced Serum Endotoxin Increase And Small Bowel Inflammation In Mice, Dora Lippai, Shashi Bala, Donna Catalano, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND: Chronic alcohol impairs gut barrier function and induces inflammatory cytokines. The effects of acute alcohol binge on the gut are partially understood. Micro-RNA-155 (miR-155), a modulator of cytokine and T-cell immune response in the gut, stabilizes tumor necrosis factor-alpha (TNFalpha) mRNA. Here, we investigated the role of the inflammation modulator miR-155 as well as the effects of acute binge and chronic alcohol feeding in the small bowel (SB) in mice. METHODS: For the acute alcohol binge, wild-type (WT) mice received 5 g/kg 50% alcohol/d or equal amount of water oral gavage for 3 days. WT and miR-155-deficient (miR-155-knockout [KO]) …


Human Type 2 Myeloid Dendritic Cells Produce Interferon-Lambda And Amplify Interferon-Alpha In Response To Hepatitis C Virus Infection, Shuye Zhang, Karen Kodys, Kui Li, Gyongyi Szabo Sep 2014

Human Type 2 Myeloid Dendritic Cells Produce Interferon-Lambda And Amplify Interferon-Alpha In Response To Hepatitis C Virus Infection, Shuye Zhang, Karen Kodys, Kui Li, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND and AIMS: The type III interferons (IFN-lambdas: interleukin [IL]-28a, IL-28b, and IL-29) have important roles in hepatitis C virus (HCV) infection, but little is understood about what cells produce these cytokines or how production is activated. We investigated whether human immune cells recognize HCV-infected cells and respond by producing IFN-lambda. METHODS: We cultured healthy human peripheral blood mononuclear cells (PBMCs) with different populations of immune cells and Japanese fulminant hepatitis-1 (JFH-1) HCV-infected Huh7.5 (cell culture-derived HCV particles [HCVcc]/Huh7.5) cells. RESULTS: Human PBMCs recognized HCVcc/Huh7.5 cells and responded by producing IFN-alpha, IFN-gamma, and IFN-lambda. A rare subset of myeloid dendritic …


Converging Actions Of Alcohol On Liver And Brain Immune Signaling, Gyongyi Szabo, Dora Lippai Sep 2014

Converging Actions Of Alcohol On Liver And Brain Immune Signaling, Gyongyi Szabo, Dora Lippai

Gyongyi Szabo

Chronic excessive alcohol consumption results in inflammation in multiple organs, including the brain. While the contribution of neuroinflammation to alcohol-related cognitive dysfunction and behavioral alterations is established, the mechanisms by which alcohol triggers inflammation in the brain are only partially understood. There are acute and long-term alterations in brain function due to intercellular and intracellular changes of different cell types as a result of alcohol consumption. This review focuses on the alcohol-induced proinflammatory cellular and molecular changes in the central nervous system. Alcohol passes through the blood-brain barrier and alters neurotransmission. Alcohol use activates microglia and astrocyte, contributing to neurodegeneration …


Both Bone Marrow-Derived And Non-Bone Marrow-Derived Cells Contribute To Aim2 And Nlrp3 Inflammasome Activation In A Myd88-Dependent Manner In Dietary Steatohepatitis, Timea Csak, Arun Pillai, Michal Ganz, Dora Lippai, Jan Petrasek, Jin-Kyu Park, Karen Kodys, Angela Dolganiuc, Evelyn Kurt-Jones, Gyongyi Szabo Sep 2014

Both Bone Marrow-Derived And Non-Bone Marrow-Derived Cells Contribute To Aim2 And Nlrp3 Inflammasome Activation In A Myd88-Dependent Manner In Dietary Steatohepatitis, Timea Csak, Arun Pillai, Michal Ganz, Dora Lippai, Jan Petrasek, Jin-Kyu Park, Karen Kodys, Angela Dolganiuc, Evelyn Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND and AIMS: Inflammation promotes the progression of non-alcoholic steatohepatitis (NASH). Toll-like receptor 4 (TLR4) and TLR9 activation through myeloid differentiation primary response gene 88 (MyD88) and production of mature interleukin-1beta (IL-1beta) via inflammasome activation contribute to steatohepatitis. Here, we investigated the inter-relationship between TLR signalling and inflammasome activation in dietary steatohepatitis.

METHODS: Wild type (WT), TLR4- and MyD88-deficient (KO) mice received methionine-choline-deficient (MCD) or -supplemented (MCS) diets for 5 weeks and a subset was challenged with TLR9 ligand CpG-DNA.

RESULTS: TLR4, TLR9, AIM2 (absent in melanoma 2) and NLRP3 (NLR family pyrin domain containing 3) inflammasome mRNA, and mature …


Toll-Like Receptors In Liver Disease, Jan Petrasek, Timea Csak, Gyongyi Szabo Sep 2014

Toll-Like Receptors In Liver Disease, Jan Petrasek, Timea Csak, Gyongyi Szabo

Gyongyi Szabo

Activation of inflammatory signaling pathways is of central importance in the pathogenesis of alcoholic liver disease (ALD) and nonalcoholic steatohepatitis (NASH). Recent studies demonstrated that Toll-like receptors, the sensors of microbial and endogenous danger signals, are expressed and activated in innate immune cells as well as in parenchymal cells in the liver and thereby contribute to ALD and NASH. In this review, we emphasize the importance of gut-derived endotoxin and its recognition by TLR4 in the liver. The significance of TLR-induced intracellular signaling pathways and cytokine production as well as the contribution of individual cell types to the inflammation is …


Exosome-Mediated Delivery Of Functionally Active Mirna-155 Inhibitor To Macrophages, Fatemeh Momen-Heravi, Shashi Bala, Terence Bukong, Gyongyi Szabo Sep 2014

Exosome-Mediated Delivery Of Functionally Active Mirna-155 Inhibitor To Macrophages, Fatemeh Momen-Heravi, Shashi Bala, Terence Bukong, Gyongyi Szabo

Gyongyi Szabo

Exosomes, membranous nanovesicles, naturally carry bio-macromolecules and play pivotal roles in both physiological intercellular crosstalk and disease pathogenesis. Here, we showed that B cell-derived exosomes can function as vehicles to deliver exogenous miRNA-155 mimic or inhibitor into hepatocytes or macrophages, respectively. Stimulation of B cells significantly increased exosome production. Unlike in parental cells, baseline level of miRNA-155 was very low in exosomes derived from stimulated B cells. Exosomes loaded with a miRNA-155 mimic significantly increased miRNA-155 levels in primary mouse hepatocytes and the liver of miRNA-155 knockout mice. Treatment of RAW macrophages with miRNA-155 inhibitor loaded exosomes resulted in statistically …


Immune And Inflammatory Pathways In Nash, Michal Ganz, Gyongyi Szabo Sep 2014

Immune And Inflammatory Pathways In Nash, Michal Ganz, Gyongyi Szabo

Gyongyi Szabo

Immune and inflammatory pathways have a central role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Both the innate and adaptive immune systems contribute to the development of NAFLD. Pathogen-associated molecular patterns and danger-associated molecular patterns are known to activate a variety of pattern-recognition receptors that result in inflammation. The key features of the immune system and inflammatory pathways in the development of NAFLD are discussed in this review.


Innate Immune Cell Networking In Hepatitis C Virus Infection, Banishree Saha, Gyongyi Szabo Sep 2014

Innate Immune Cell Networking In Hepatitis C Virus Infection, Banishree Saha, Gyongyi Szabo

Gyongyi Szabo

Persistent viral infection, such as HCV infection, is the result of the inability of the host immune system to mount a successful antiviral response, as well as the escape strategies devised by the virus. Although each individual component of the host immune system plays important roles in antiviral immunity, the interactive network of immune cells as a whole acts against the virus. The innate immune system forms the first line of host defense against viral infection, and thus, virus elimination or chronic HCV infection is linked to the direct outcome of the interactions between the various innate immune cells and …


Dengue: Defining Protective Versus Pathologic Immunity, Alan Rothman Aug 2014

Dengue: Defining Protective Versus Pathologic Immunity, Alan Rothman

Alan Rothman

Dengue is an expanding public health problem, and an effective vaccine remains elusive. This review discusses how the significant influence of sequential infection with different dengue virus serotypes on the severity of disease can be viewed in terms of beneficial and detrimental effects of heterologous immunity. A more complete understanding of these effects is likely to be critical for predicting optimal vaccine-induced immune responses.


T Cell Receptor Vbeta Gene Usage In Thai Children With Dengue Virus Infection, Susan Gagnon, Anita Leporati, Sharone Green, Siripen Kalayanarooj, David Vaughn, Henry Stephens, Saroj Suntayakorn, Ichiro Kurane, Francis Ennis, Alan Rothman Aug 2014

T Cell Receptor Vbeta Gene Usage In Thai Children With Dengue Virus Infection, Susan Gagnon, Anita Leporati, Sharone Green, Siripen Kalayanarooj, David Vaughn, Henry Stephens, Saroj Suntayakorn, Ichiro Kurane, Francis Ennis, Alan Rothman

Alan Rothman

T lymphocyte activation during dengue is thought to contribute to the pathogenesis of dengue hemorrhagic fever (DHF). We examined the T cell receptor Vbeta gene usage by a reverse transcriptase-polymerase chain reaction assay during infection and after recovery in 13 children with DHF and 13 children with dengue fever (DF). There was no deletion of specific Vbeta gene families. We detected significant expansions in usage of single Vbeta families in six subjects with DHF and three subjects with DF over the course of infection, but these did not show an association with clinical diagnosis, viral serotype, or HLA alleles. Differences …


Quantitation Of Cd8+ T Cell Responses To Newly Identified Hla-A*0201-Restricted T Cell Epitopes Conserved Among Vaccinia And Variola (Smallpox) Viruses, Masanori Terajima, John Cruz, Gregory Raines, Elizabeth Kilpatrick, Jeffrey Kennedy, Alan Rothman, Francis Ennis Aug 2014

Quantitation Of Cd8+ T Cell Responses To Newly Identified Hla-A*0201-Restricted T Cell Epitopes Conserved Among Vaccinia And Variola (Smallpox) Viruses, Masanori Terajima, John Cruz, Gregory Raines, Elizabeth Kilpatrick, Jeffrey Kennedy, Alan Rothman, Francis Ennis

Alan Rothman

Immunization with vaccinia virus resulted in long-lasting protection against smallpox and was the approach used to eliminate natural smallpox infections worldwide. Due to the concern about the potential use of smallpox virus as a bioweapon, smallpox vaccination is currently being reintroduced. Severe complications from vaccination were associated with congenital or acquired T cell deficiencies, but not with congenital agammaglobulinemia, suggesting the importance of T cell immunity in recovery from infection. In this report, we identified two CD8+ T cell epitopes restricted by the most common human major histocompatibility complex (MHC) class I allele, HLA-A*0201. Both epitopes are highly conserved in …


Inflammasomes And Host Defenses Against Bacterial Infections, Gregory Vladimer, Robyn Marty-Roix, Shubhendu Ghosh, Dan Weng, Egil Lien May 2014

Inflammasomes And Host Defenses Against Bacterial Infections, Gregory Vladimer, Robyn Marty-Roix, Shubhendu Ghosh, Dan Weng, Egil Lien

Robyn Marty-Roix

The inflammasome has emerged as an important molecular protein complex which initiates proteolytic processing of pro-IL-1β and pro-IL-18 into mature inflammatory cytokines. In addition, inflammasomes initiate pyroptotic cell death that may be independent of those cytokines. Inflammasomes are central to elicit innate immune responses against many pathogens, and are key components in the induction of host defenses following bacterial infection. Here, we review recent discoveries related to NLRP1, NLRP3, NLRC4, NLRP6, NLRP7, NLRP12 and AIM2-mediated recognition of bacteria. Mechanisms for inflammasome activation and regulation are now suggested to involve kinases such as PKR and PKCδ, ligand binding proteins such as …