Introduction and immunopathogenesis of acquired immune deficiency syndrome

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Sudharshan S

2008-01-01

Full Text Available India has a large number of patients with acquired immune deficiency syndrome (AIDS, the third largest population of this group in the world. This disease was first described in patients with Pneumocystis pneumonia in 1981. Ocular lesions can occur at any stage of the disease but are more commonly seen at the late stages. Human immunodeficiency virus (HIV, the causative agent of AIDS is a retrovirus with RNA genome and a unique ′Reverse transcriptase enzyme′ and is of two types, HIV-1 and 2. Most human diseases are caused by HIV-1. The HIV-1 subtypes prevalent in India are A, B and C. They act predominantly by reducing the CD4+ cells and thus the patient becomes susceptible to opportunistic infections. High viral titers in the peripheral blood during primary infection lead to decrease in the number of CD4+ T lymphocytes. Onset of HIV-1-specific cellular immune response with synthesis of HIV-1 specific antibodies leads to the decline of plasma viral load and chronification of HIV-1 infection. However, the asymptomatic stage of infection may lead to persistent viral replication and a rapid turnover of plasma virions which is the clinical latency. During this period, there is further decrease in the CD4+ counts which makes the patient′s immune system incapable of controlling opportunistic pathogens and thus life-threatening AIDS-defining diseases emerge. Advent of highly active antiretroviral treatment (HAART has revolutionized the management of AIDS though there is associated increased development of immune recovery uveitis in a few of these patients.

Oral or parenteral administration of replication-deficient adenoviruses expressing the measles virus haemagglutinin and fusion proteins: protective immune responses in rodents.

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Fooks, A R; Jeevarajah, D; Lee, J; Warnes, A; Niewiesk, S; ter Meulen, V; Stephenson, J R; Clegg, J C

1998-05-01

The genes encoding the measles virus (MV) haemagglutinin (H) and fusion (F) proteins were placed under the control of the human cytomegalovirus immediate early promoter in a replication-deficient adenovirus vector. Immunofluorescence and radioimmune precipitation demonstrated the synthesis of each protein and biological activity was confirmed by the detection of haemadsorption and fusion activities in infected cells. Oral as well as parenteral administration of the H-expressing recombinant adenovirus elicited a significant protective response in mice challenged with MV. While the F-expressing adenovirus failed to protect mice, cotton rats immunized with either the H- or F-expressing recombinant showed reduced MV replication in the lungs. Antibodies elicited in mice following immunization with either recombinant had no in vitro neutralizing activity, suggesting a protective mechanism involving a cell-mediated immune response. This study demonstrates the feasibility of using oral administration of adenovirus recombinants to induce protective responses to heterologous proteins.

GATA2 Deficiency and Epstein–Barr Virus Disease

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Jeffrey I. Cohen

2017-12-01

Full Text Available GATA2 is a transcription factor that binds to the promoter of hematopoietic genes. Mutations in one copy of the gene are associated with haploinsufficiency and reduced levels of protein. This results in reduced numbers of several cell types important for immune surveillance including dendritic cells, monocytes, CD4, and NK cells, as well as impaired NK cell function. Recently, GATA2 has been associated with several different presentations of severe Epstein–Barr virus (EBV disease including primary infection requiring repeated hospitalizations, chronic active EBV disease, EBV-associated hydroa vacciniforme with hemophagocytosis, and EBV-positive smooth muscle tumors. EBV was found predominantly in B cells in each of the cases in which it was studied, unlike most cases of chronic active EBV disease in which the virus is usually present in T or NK cells. The variety of EBV-associated diseases seen in patients with GATA2 deficiency suggest that additional forms of severe EBV disease may be found in patients with GATA2 deficiency in the future.

GATA2 Deficiency and Epstein-Barr Virus Disease.

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Cohen, Jeffrey I

2017-01-01

GATA2 is a transcription factor that binds to the promoter of hematopoietic genes. Mutations in one copy of the gene are associated with haploinsufficiency and reduced levels of protein. This results in reduced numbers of several cell types important for immune surveillance including dendritic cells, monocytes, CD4, and NK cells, as well as impaired NK cell function. Recently, GATA2 has been associated with several different presentations of severe Epstein-Barr virus (EBV) disease including primary infection requiring repeated hospitalizations, chronic active EBV disease, EBV-associated hydroa vacciniforme with hemophagocytosis, and EBV-positive smooth muscle tumors. EBV was found predominantly in B cells in each of the cases in which it was studied, unlike most cases of chronic active EBV disease in which the virus is usually present in T or NK cells. The variety of EBV-associated diseases seen in patients with GATA2 deficiency suggest that additional forms of severe EBV disease may be found in patients with GATA2 deficiency in the future.

Polyomavirus specific cellular immunity: from BK-virus-specific cellular immunity to BK-virus-associated nephropathy ?

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manon edekeyser

2015-06-01

Full Text Available In renal transplantation, BK-virus-associated nephropathy has emerged as a major complication, with a prevalence of 5–10% and graft loss in >50% of cases. BK-virus is a member of the Polyomavirus family and rarely induces apparent clinical disease in the general population. However, replication of polyomaviruses, associated with significant organ disease, is observed in patients with acquired immunosuppression, which suggests a critical role for virus-specific cellular immunity to control virus replication and prevent chronic disease. Monitoring of specific immunity combined with viral load could be used to individually assess the risk of viral reactivation and virus control. We review the current knowledge on BK-virus specific cellular immunity and, more specifically, in immunocompromised patients. In the future, immune-based therapies could allow us to treat and prevent BK-virus-associated nephropathy.

Tolerance and immunity in mice infected with herpes simplex virus: simultaneous induction of protective immunity and tolerance to delayed-type hypersensitivity.

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Nash, A A; Gell, P G; Wildy, P

1981-05-01

Unresponsiveness to delayed type hypersensitivity was induced in mice following an intravenous injection of herpes simplex virus. The principal tolerogens used were thymidine kinase-deficient virus mutants which grow poorly in vivo; u.v.-inactivated and to a lesser extent formalin-inactivated virus were also tolerogenic. The tolerance induced was specific for the virus type. Despite the tolerance to delayed hypersensitivity, anti-viral immunity is present as determined by the rapid inactivation of infectious virus. The mechanism of tolerance to herpes virus and the importance of these observations for the pathogenesis of viral disease is discussed.

Effect of traditional Chinese medicine for treating human immunodeficiency virus infections and acquired immune deficiency syndrome: Boosting immune and alleviating symptoms.

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Zou, Wen; Wang, Jian; Liu, Ying

2016-01-01

To respond to the human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) epidemic in China, the integration of antiretroviral therapy (ART) and traditional Chinese medicine (TCM) has important implications in health outcomes, especially in China where the use of TCM is widespread. The National Free TCM Pilot Program for HIV Infected People began in 5 provinces (Henan, Hebei, Anhui, Hubei, and Guangdong) in 2004, and quickly scaled up to 19 provinces, autonomous regions, and municipalities in China including some places with high prevalence, 26,276 adults have been treated thus far. Usually, people with HIV infection seek TCM for four main reasons: to enhance immune function, to treat symptoms, to improve quality of life, and to reduce side effects related to medications. Evidences from randomized controlled clinical trials suggested some beneficial effects of use of traditional Chinese herbal medicine for HIV infections and AIDS. More proofs from large, well-designed, rigorous trials is needed to give firm support. Challenges include interaction between herbs and antiretroviral drugs, stigma and discrimination. The Free TCM Program has made considerable progress in providing the necessary alternative care and treatment for HIV-infected people in China, and has strong government support for continued improvement and expansion, establishing and improving a work mechanism integrating Chinese and Western medicines.

The role of CD4+ T cells in cell-mediated immunity to LCMV: studies in MHC class I and class II deficient mice

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Christensen, Jan Pravsgaard; Marker, O; Thomsen, Allan Randrup

1994-01-01

Parameters of the virus-specific T-cell response were analysed in order to dissect the contribution of CD4+ and CD8+ T cells to cell-mediated immunity to lymphocytic choriomeningitis virus. In MHC class II deficient mice, initial T-cell responsiveness was not impaired, but virus clearance...... was delayed, and virus-specific Td activity declined more rapidly. Furthermore, class I restricted Tc memory appeared to be impaired in these mice. To directly evaluate the role of CD4+ cells in virus clearance and T-cell mediated inflammation, MHC class I deficient mice were also studied. No virus...... exudate. This low-grade response was associated with some degree of virus control as organ titres were lower in these animals than in matched T-cell deficient nu/nu mice or class I deficient mice treated with anti-CD4 monoclonal antibody. This confirms that CD4+ cells are not needed to induce a virus...

Enveloped viruses disable innate immune responses in dendritic cells by direct activation of TAM receptors.

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Bhattacharyya, Suchita; Zagórska, Anna; Lew, Erin D; Shrestha, Bimmi; Rothlin, Carla V; Naughton, John; Diamond, Michael S; Lemke, Greg; Young, John A T

2013-08-14

Upon activation by the ligands Gas6 and Protein S, Tyro3/Axl/Mer (TAM) receptor tyrosine kinases promote phagocytic clearance of apoptotic cells and downregulate immune responses initiated by Toll-like receptors and type I interferons (IFNs). Many enveloped viruses display the phospholipid phosphatidylserine on their membranes, through which they bind Gas6 and Protein S and engage TAM receptors. We find that ligand-coated viruses activate TAM receptors on dendritic cells (DCs), dampen type I IFN signaling, and thereby evade host immunity and promote infection. Upon virus challenge, TAM-deficient DCs display type I IFN responses that are elevated in comparison to wild-type cells. As a consequence, TAM-deficient DCs are relatively resistant to infection by flaviviruses and pseudotyped retroviruses, but infection can be restored with neutralizing type I IFN antibodies. Correspondingly, a TAM kinase inhibitor antagonizes the infection of wild-type DCs. Thus, TAM receptors are engaged by viruses in order to attenuate type I IFN signaling and represent potential therapeutic targets. Copyright © 2013 Elsevier Inc. All rights reserved.

Human Immunodeficiency Virus Type 1-Hepatitis C Virus Coinfection: Intraindividual Comparison of Cellular Immune Responses against Two Persistent Viruses

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Lauer, Georg M.; Nguyen, Tam N.; Day, Cheryl L.; Robbins, Gregory K.; Flynn, Theresa; McGowan, Katherine; Rosenberg, Eric S.; Lucas, Michaela; Klenerman, Paul; Chung, Raymond T.; Walker, Bruce D.

2002-01-01

Both human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) lead to chronic infection in a high percentage of persons, and an expanding epidemic of HIV-1-HCV coinfection has recently been identified. These individuals provide an opportunity for simultaneous assessment of immune responses to two viral infections associated with chronic plasma viremia. In this study we analyzed the breadth and magnitude of the CD8+- and CD4+-T-lymphocyte responses in 22 individuals infected wit...

Persistent hepatitis virus infection and immune homeostasis

OpenAIRE

ZHOU Yun

2014-01-01

Homeostasis between the host and viruses is naturally maintained. On the one hand, the immune system activates the immune response to kill or eliminate viruses; on the other hand, the immune system controls the immune response to maintain immune homeostasis. The cause of persistent infections with hepatitis viruses such as HBV and HCV is that viral molecules damage the immune system of the host and their variants escape immune clearance. Long-term coexistence of the host and viruses is the pr...

Antibody quality and protection from lethal Ebola virus challenge in nonhuman primates immunized with rabies virus based bivalent vaccine.

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Blaney, Joseph E; Marzi, Andrea; Willet, Mallory; Papaneri, Amy B; Wirblich, Christoph; Feldmann, Friederike; Holbrook, Michael; Jahrling, Peter; Feldmann, Heinz; Schnell, Matthias J

2013-01-01

We have previously described the generation of a novel Ebola virus (EBOV) vaccine platform based on (a) replication-competent rabies virus (RABV), (b) replication-deficient RABV, or (c) chemically inactivated RABV expressing EBOV glycoprotein (GP). Mouse studies demonstrated safety, immunogenicity, and protective efficacy of these live or inactivated RABV/EBOV vaccines. Here, we evaluated these vaccines in nonhuman primates. Our results indicate that all three vaccines do induce potent immune responses against both RABV and EBOV, while the protection of immunized animals against EBOV was largely dependent on the quality of humoral immune response against EBOV GP. We also determined if the induced antibodies against EBOV GP differ in their target, affinity, or the isotype. Our results show that IgG1-biased humoral responses as well as high levels of GP-specific antibodies were beneficial for the control of EBOV infection after immunization. These results further support the concept that a successful EBOV vaccine needs to induce strong antibodies against EBOV. We also showed that a dual vaccine against RABV and filoviruses is achievable; therefore addressing concerns for the marketability of this urgently needed vaccine.

Antibody quality and protection from lethal Ebola virus challenge in nonhuman primates immunized with rabies virus based bivalent vaccine.

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Joseph E Blaney

Full Text Available We have previously described the generation of a novel Ebola virus (EBOV vaccine platform based on (a replication-competent rabies virus (RABV, (b replication-deficient RABV, or (c chemically inactivated RABV expressing EBOV glycoprotein (GP. Mouse studies demonstrated safety, immunogenicity, and protective efficacy of these live or inactivated RABV/EBOV vaccines. Here, we evaluated these vaccines in nonhuman primates. Our results indicate that all three vaccines do induce potent immune responses against both RABV and EBOV, while the protection of immunized animals against EBOV was largely dependent on the quality of humoral immune response against EBOV GP. We also determined if the induced antibodies against EBOV GP differ in their target, affinity, or the isotype. Our results show that IgG1-biased humoral responses as well as high levels of GP-specific antibodies were beneficial for the control of EBOV infection after immunization. These results further support the concept that a successful EBOV vaccine needs to induce strong antibodies against EBOV. We also showed that a dual vaccine against RABV and filoviruses is achievable; therefore addressing concerns for the marketability of this urgently needed vaccine.

Immunity to sporozoite-induced malaria infection in mice. I. The effect of immunization of T and B cell-deficient mice

International Nuclear Information System (INIS)

Chen, D.H.; Tigelaar, R.E.; Weinbaum, F.I.

1977-01-01

The cellular basis of immunity to sporozoites was investigated by examining the effect of immunization of T and B cell-deficient C57BL/6N x BALB/c AnN F 1 (BLCF 1 ) mice compared to immunocompetent controls. Immunization of T cell-deficient (ATX-BM-ATS) BLCF 1 mice with x-irradiated sporozoites did not result in the generation of protective immunity. The same immunization protocols protected all immunocompetent controls. In contrast, B cell-deficient (μ-suppressed) BLCF 1 mice were protected by immunization in the majority of cases. The absence of detectable serum circumsporozoite precipitins or sporozoite neutralizing activity in the μ-suppressed mice that resisted a sporozoite challenge suggests a minor role for these humoral factors in protection. These data demonstrate a preeminent role for T cells in the induction of protective immunity in BLCF 1 mice against a P. berghei sporozoite infection

Genotype I of Japanese Encephalitis Virus Virus-like Particles Elicit Sterilizing Immunity against Genotype I and III Viral Challenge in Swine.

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Fan, Yi-Chin; Chen, Jo-Mei; Lin, Jen-Wei; Chen, Yi-Ying; Wu, Guan-Hong; Su, Kuan-Hsuan; Chiou, Ming-Tang; Wu, Shang-Rung; Yin, Ji-Hang; Liao, Jiunn-Wang; Chang, Gwong-Jen J; Chiou, Shyan-Song

2018-05-10

Swine are a critical amplifying host involved in human Japanese encephalitis (JE) outbreaks. Cross-genotypic immunogenicity and sterile protection are important for the current genotype III (GIII) virus-derived vaccines in swine, especially now that emerging genotype I (GI) JE virus (JEV) has replaced GIII virus as the dominant strain. Herein, we aimed to develop a system to generate GI JEV virus-like particles (VLPs) and evaluate the immunogenicity and protection of the GI vaccine candidate in mice and specific pathogen-free swine. A CHO-heparan sulfate-deficient (CHO-HS(-)) cell clone, named 51-10 clone, stably expressing GI-JEV VLP was selected and continually secreted GI VLPs without signs of cell fusion. 51-10 VLPs formed a homogeneously empty-particle morphology and exhibited similar antigenic activity as GI virus. GI VLP-immunized mice showed balanced cross-neutralizing antibody titers against GI to GIV viruses (50% focus-reduction micro-neutralization assay titers 71 to 240) as well as potent protection against GI or GIII virus infection. GI VLP-immunized swine challenged with GI or GIII viruses showed no fever, viremia, or viral RNA in tonsils, lymph nodes, and brains as compared with phosphate buffered saline-immunized swine. We thus conclude GI VLPs can provide sterile protection against GI and GIII viruses in swine.

Infection of mice with a human influenza A/H3N2 virus induces protective immunity against lethal infection with influenza A/H5N1 virus.

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Kreijtz, J H C M; Bodewes, R; van den Brand, J M A; de Mutsert, G; Baas, C; van Amerongen, G; Fouchier, R A M; Osterhaus, A D M E; Rimmelzwaan, G F

2009-08-06

The transmission of highly pathogenic avian influenza (HPAI) A viruses of the H5N1 subtype from poultry to man and the high case fatality rate fuels the fear for a pandemic outbreak caused by these viruses. However, prior infections with seasonal influenza A/H1N1 and A/H3N2 viruses induce heterosubtypic immunity that could afford a certain degree of protection against infection with the HPAI A/H5N1 viruses, which are distantly related to the human influenza A viruses. To assess the protective efficacy of such heterosubtypic immunity mice were infected with human influenza virus A/Hong Kong/2/68 (H3N2) 4 weeks prior to a lethal infection with HPAI virus A/Indonesia/5/05 (H5N1). Prior infection with influenza virus A/Hong Kong/2/68 reduced clinical signs, body weight loss, mortality and virus replication in the lungs as compared to naive mice infected with HPAI virus A/Indonesia/5/05. Priming by infection with respiratory syncytial virus, a non-related virus did not have a beneficial effect on the outcome of A/H5N1 infections, indicating that adaptive immune responses were responsible for the protective effect. In mice primed by infection with influenza A/H3N2 virus cytotoxic T lymphocytes (CTL) specific for NP(366-374) epitope ASNENMDAM and PA(224-232) SCLENFRAYV were observed. A small proportion of these CTL was cross-reactive with the peptide variant derived from the influenza A/H5N1 virus (ASNENMEVM and SSLENFRAYV respectively) and upon challenge infection with the influenza A/H5N1 virus cross-reactive CTL were selectively expanded. These CTL, in addition to those directed to conserved epitopes, shared by the influenza A/H3N2 and A/H5N1 viruses, most likely contributed to accelerated clearance of the influenza A/H5N1 virus infection. Although also other arms of the adaptive immune response may contribute to heterosubtypic immunity, the induction of virus-specific CTL may be an attractive target for development of broad protective vaccines. Furthermore the

Extensive immune-mediated hippocampal damage in mice surviving infection with neuroadapted Sindbis virus

International Nuclear Information System (INIS)

Kimura, Takashi; Griffin, Diane E.

2003-01-01

Viral infections of the central nervous system and immune responses to these infections cause a variety of neurological diseases. Infection of weanling mice with Sindbis virus causes acute nonfatal encephalomyelitis followed by clearance of infectious virus, but persistence of viral RNA. Infection with a neuroadapted strain of Sindbis virus (NSV) causes fatal encephalomyelitis, but passive transfer of immune serum after infection protects from fatal disease and infectious virus is cleared. To determine whether persistent NSV RNA is associated with neurological damage, we examined the brains of recovered mice and found progressive loss of the hippocampal gyrus, adjacent white matter, and deep cerebral cortex associated with mononuclear cell infiltration. Mice deficient in CD4 + T cells showed less tissue loss, while mice lacking CD8 + T cells showed lesions comparable to those in immunocompetent mice. Mice deficient in both CD4 + and CD8 + T cells developed severe tissue loss similar to immunocompetent mice and this was associated with extensive infiltration of macrophages. The number of CD4 + cells and macrophage/microglial cells, but not CD8 + cells, infiltrating the hippocampal gyrus was correlated with the number of terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling positive pyramidal neurons. These results suggest that CD4 + T cells can promote progressive neuronal death and tissue injury, despite clearance of infectious virus

Live vaccinia-rabies virus recombinants, but not an inactivated rabies virus cell culture vaccine, protect B-lymphocyte-deficient A/WySnJ mice against rabies: considerations of recombinant defective poxviruses for rabies immunization of immunocompromised individuals.

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Lodmell, Donald L; Esposito, Joseph J; Ewalt, Larry C

2004-09-03

Presently, commercially available cell culture rabies vaccines for humans and animals consist of the five inactivated rabies virus proteins. The vaccines elicit a CD4+ helper T-cell response and a humoral B-cell response against the viral glycoprotein (G) resulting in the production of virus neutralizing antibody. Antibody against the viral nucleoprotein (N) is also present, but the mechanism(s) of its protection is unclear. HIV-infected individuals with low CD4+ T-lymphocyte counts and individuals undergoing treatment with immunosuppressive drugs have an impaired neutralizing antibody response after pre- and post-exposure immunization with rabies cell culture vaccines. Here we show the efficacy of live vaccinia-rabies virus recombinants, but not a cell culture vaccine consisting of inactivated rabies virus, to elicit elevated levels of neutralizing antibody in B-lymphocyte deficient A/WySnJ mice. The cell culture vaccine also failed to protect the mice, whereas a single immunization of a vaccinia recombinant expressing the rabies virus G or co-expressing G and N equally protected the mice up to 18 months after vaccination. The data suggest that recombinant poxviruses expressing the rabies virus G, in particular replication defective poxviruses such as canarypox or MVA vaccinia virus that undergo abortive replication in non-avian cells, or the attenuated vaccinia virus NYVAC, should be evaluated as rabies vaccines in immunocompromised individuals.

Memory immune responses against pandemic (H1N1 2009 influenza virus induced by a whole particle vaccine in cynomolgus monkeys carrying Mafa-A1*052:02.

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Masahiko Arikata

Full Text Available We made an H1N1 vaccine candidate from a virus library consisting of 144 ( = 16 HA×9 NA non-pathogenic influenza A viruses and examined its protective effects against a pandemic (2009 H1N1 strain using immunologically naïve cynomolgus macaques to exclude preexisting immunity and to employ a preclinical study since preexisting immunity in humans previously vaccinated or infected with influenza virus might make comparison of vaccine efficacy difficult. Furthermore, macaques carrying a major histocompatibility complex class I molecule, Mafa-A1*052:02, were used to analyze peptide-specific CD8(+ T cell responses. Sera of macaques immunized with an inactivated whole particle formulation without addition of an adjuvant showed higher neutralization titers against the vaccine strain A/Hokkaido/2/1981 (H1N1 than did sera of macaques immunized with a split formulation. Neutralization activities against the pandemic strain A/Narita/1/2009 (H1N1 in sera of macaques immunized twice with the split vaccine reached levels similar to those in sera of macaques immunized once with the whole particle vaccine. After inoculation with the pandemic virus, the virus was detected in nasal samples of unvaccinated macaques for 6 days after infection and for 2.67 days and 5.33 days on average in macaques vaccinated with the whole particle vaccine and the split vaccine, respectively. After the challenge infection, recall neutralizing antibody responses against the pandemic virus and CD8(+ T cell responses specific for nucleoprotein peptide NP262-270 bound to Mafa-A1*052:02 in macaques vaccinated with the whole particle vaccine were observed more promptly or more vigorously than those in macaques vaccinated with the split vaccine. These findings demonstrated that the vaccine derived from our virus library was effective for pandemic virus infection in macaques and that the whole particle vaccine conferred more effective memory and broader cross-reactive immune responses

CTA1-DD adjuvant promotes strong immunity against human immunodeficiency virus type 1 envelope glycoproteins following mucosal immunization.

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Sundling, Christopher; Schön, Karin; Mörner, Andreas; Forsell, Mattias N E; Wyatt, Richard T; Thorstensson, Rigmor; Karlsson Hedestam, Gunilla B; Lycke, Nils Y

2008-12-01

Strategies to induce potent and broad antibody responses against the human immunodeficiency virus type 1 (HIV-1) envelope glycoproteins (Env) at both systemic and mucosal sites represent a central goal for HIV-1 vaccine development. Here, we show that the non-toxic CTA1-DD adjuvant promoted mucosal and systemic humoral and cell-mediated immune responses following intranasal (i.n.) immunizations with trimeric or monomeric forms of HIV-1 Env in mice and in non-human primates. Env-specific IgG subclasses in the serum of immunized mice reflected a balanced Th1/Th2 type of response. Strikingly, i.n. immunizations with Env and the CTA1-DD adjuvant induced substantial levels of mucosal anti-Env IgA in bronchial alveolar lavage and also detectable levels in vaginal secretions. By contrast, parenteral immunizations of Env formulated in Ribi did not stimulate mucosal IgA responses, while the two adjuvants induced a similar distribution of Env-specific IgG-subclasses in serum. A single parenteral boost with Env in Ribi adjuvant into mice previously primed i.n. with Env and CTA1-DD, augmented the serum anti-Env IgG levels to similar magnitudes as those observed after three intraperitoneal immunizations with Env in Ribi. The augmenting potency of CTA1-DD was similar to that of LTK63 or CpG oligodeoxynucleotides (ODN). However, in contrast to CpG ODN, the effect of CTA1-DD and LTK63 appeared to be independent of MyD88 and toll-like receptor signalling. This is the first demonstration that CTA1-DD augments specific immune responses also in non-human primates, suggesting that this adjuvant could be explored further as a clinically safe mucosal vaccine adjuvant for humoral and cell-mediated immunity against HIV-1 Env.

PA-X protein contributes to virulence of triple-reassortant H1N2 influenza virus by suppressing early immune responses in swine.

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Xu, Guanlong; Zhang, Xuxiao; Liu, Qinfang; Bing, Guoxia; Hu, Zhe; Sun, Honglei; Xiong, Xin; Jiang, Ming; He, Qiming; Wang, Yu; Pu, Juan; Guo, Xin; Yang, Hanchun; Liu, Jinhua; Sun, Yipeng

2017-08-01

Previous studies have identified a functional role of PA-X for influenza viruses in mice and avian species; however, its role in swine remains unknown. Toward this, we constructed PA-X deficient virus (Sw-FS) in the background of a Triple-reassortment (TR) H1N2 swine influenza virus (SIV) to assess the impact of PA-X in viral virulence in pigs. Expression of PA-X in TR H1N2 SIV enhanced viral replication and host protein synthesis shutoff, and inhibited the mRNA levels of type I IFNs and proinflammatory cytokines in porcine cells. A delay of proinflammatory responses was observed in lungs of pigs infected by wild type SIV (Sw-WT) compared to Sw-FS. Furthermore, Sw-WT virus replicated and transmitted more efficiently than Sw-FS in pigs. These results highlight the importance of PA-X in the moderation of virulence and immune responses of TR SIV in swine, which indicated that PA-X is a pro-virulence factor in TR SIV in pigs. Copyright © 2017 Elsevier Inc. All rights reserved.

Induction of immunity to human immunodeficiency virus type-1 by vaccination.

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McElrath, M Juliana; Haynes, Barton F

2010-10-29

Recent findings have brought optimism that development of a successful human immunodeficiency virus type-1 (HIV-1) vaccine lies within reach. Studies of early events in HIV-1 infection have revealed when and where HIV-1 is potentially vulnerable to vaccine-targeted immune responses. With technical advances in human antibody production, clues about how antibodies recognize HIV-1 envelope proteins have uncovered new targets for immunogen design. A recent vaccine regimen has shown modest efficacy against HIV-1 acquisition. However, inducing long-term T and B cell memory and coping with HIV-1 diversity remain high priorities. Mediators of innate immunity may play pivotal roles in blocking infection and shaping immunity; vaccine strategies to capture these activities are under investigation. Challenges remain in integrating basic, preclinical and clinical research to improve predictions of types of immunity associated with vaccine efficacy, to apply these insights to immunogen design, and to accelerate evaluation of vaccine efficacy in persons at-risk for infection. Copyright © 2010 Elsevier Inc. All rights reserved.

A Respiratory Syncytial Virus Vaccine Vectored by a Stable Chimeric and Replication-Deficient Sendai Virus Protects Mice without Inducing Enhanced Disease.

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Wiegand, Marian Alexander; Gori-Savellini, Gianni; Gandolfo, Claudia; Papa, Guido; Kaufmann, Christine; Felder, Eva; Ginori, Alessandro; Disanto, Maria Giulia; Spina, Donatella; Cusi, Maria Grazia

2017-05-15

Respiratory syncytial virus (RSV) is a major cause of severe respiratory infections in children and elderly people, and no marketed vaccine exists. In this study, we generated and analyzed a subunit vaccine against RSV based on a novel genome replication-deficient Sendai virus (SeV) vector. We inserted the RSV F protein, known to be a genetically stable antigen, into our vector in a specific way to optimize the vaccine features. By exchanging the ectodomain of the SeV F protein for its counterpart from RSV, we created a chimeric vectored vaccine that contains the RSV F protein as an essential structural component. In this way, the antigen is actively expressed on the surfaces of vaccine particles in its prefusion conformation, and as recently reported for other vectored vaccines, the occurrence of silencing mutations of the transgene in the vaccine genome can be prevented. In addition, its active gene expression contributes to further stimulation of the immune response. In order to understand the best route of immunization, we compared vaccine efficacies after intranasal (i.n.) or intramuscular (i.m.) immunization of BALB/c mice. Via both routes, substantial RSV-specific immune responses were induced, consisting of serum IgG and neutralizing antibodies, as well as cytotoxic T cells. Moreover, i.n. immunization was also able to stimulate specific mucosal IgA in the upper and lower respiratory tract. In virus challenge experiments, animals were protected against RSV infection after both i.n. and i.m. immunization without inducing vaccine-enhanced disease. Above all, the replication-deficient SeV appeared to be safe and well tolerated. IMPORTANCE Respiratory syncytial virus (RSV) is a major cause of respiratory diseases in young children and elderly people worldwide. There is a great demand for a licensed vaccine. Promising existing vaccine approaches based on live-attenuated vaccines or viral vectors have suffered from unforeseen drawbacks related to immunogenicity

The immune complex CTA1-DD/IgG adjuvant specifically targets connective tissue mast cells through FcγRIIIA and augments anti-HPV immunity after nasal immunization.

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Fang, Y; Zhang, T; Lidell, L; Xu, X; Lycke, N; Xiang, Z

2013-11-01

We have previously reported that CTA1-DD/IgG immune complexes augment antibody responses in a mast cell-dependent manner following intranasal (IN) immunizations. However, from a safety perspective, mast cell activation could preclude clinical use. Therefore, we have extended these studies and demonstrate that CTA1-DD/IgG immune complexes administered IN did not trigger an anaphylactic reaction. Importantly, CTA1-DD/IgE immune complexes did not activate mast cells. Interestingly, only connective tissue, but not mucosal, mast cells could be activated by CTA1-DD/IgG immune complexes. This effect was mediated by FcγRIIIA, only expressed on connective tissue mast cells, and found in the nasal submucosa. FcγRIIIA-deficient mice had compromised responses to immunization adjuvanted by CTA1-DD/IgG. Proof-of-concept studies revealed that IN immunized mice with human papillomavirus (HPV) type 16 L1 virus-like particles (VLP) and CTA1-DD/IgG immune complexes demonstrated strong and sustained specific antibody titers in serum and vaginal secretions. From a mast cell perspective, CTA1-DD/IgG immune complexes appear to be safe and effective mucosal adjuvants.

Recombinant Marburg viruses containing mutations in the IID region of VP35 prevent inhibition of Host immune responses.

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Albariño, César G; Wiggleton Guerrero, Lisa; Spengler, Jessica R; Uebelhoer, Luke S; Chakrabarti, Ayan K; Nichol, Stuart T; Towner, Jonathan S

2015-02-01

Previous in vitro studies have demonstrated that Ebola and Marburg virus (EBOV and MARV) VP35 antagonize the host cell immune response. Moreover, specific mutations in the IFN inhibitory domain (IID) of EBOV and MARV VP35 that abrogate their interaction with virus-derived dsRNA, lack the ability to inhibit the host immune response. To investigate the role of MARV VP35 in the context of infectious virus, we used our reverse genetics system to generate two recombinant MARVs carrying specific mutations in the IID region of VP35. Our data show that wild-type and mutant viruses grow to similar titers in interferon deficient cells, but exhibit attenuated growth in interferon-competent cells. Furthermore, in contrast to wild-type virus, both MARV mutants were unable to inhibit expression of various antiviral genes. The MARV VP35 mutants exhibit similar phenotypes to those previously described for EBOV, suggesting the existence of a shared immune-modulatory strategy between filoviruses. Published by Elsevier Inc.

Role of complement and antibodies in controlling infection with pathogenic simian immunodeficiency virus (SIV in macaques vaccinated with replication-deficient viral vectors

Directory of Open Access Journals (Sweden)

Strasak Alexander

2009-06-01

Full Text Available Abstract Background We investigated the interplay between complement and antibodies upon priming with single-cycle replicating viral vectors (SCIV encoding SIV antigens combined with Adeno5-SIV or SCIV pseudotyped with murine leukemia virus envelope boosting strategies. The vaccine was applied via spray-immunization to the tonsils of rhesus macaques and compared with systemic regimens. Results Independent of the application regimen or route, viral loads were significantly reduced after challenge with SIVmac239 (p Conclusion The heterologous prime-boost strategy with replication-deficient viral vectors administered exclusively via the tonsils did not induce any neutralizing antibodies before challenge. However, after challenge, comparable SIV-specific humoral immune responses were observed in all vaccinated animals. Immunization with single cycle immunodeficiency viruses mounts humoral immune responses comparable to live-attenuated immunodeficiency virus vaccines.

Effect of the novel influenza A (H1N1 virus in the human immune system.

Directory of Open Access Journals (Sweden)

Evangelos J Giamarellos-Bourboulis

Full Text Available BACKGROUND: The pandemic by the novel H1N1 virus has created the need to study any probable effects of that infection in the immune system of the host. METHODOLOGY/PRINCIPAL FINDINGS: Blood was sampled within the first two days of the presentation of signs of infection from 10 healthy volunteers; from 18 cases of flu-like syndrome; and from 31 cases of infection by H1N1 confirmed by reverse RT-PCR. Absolute counts of subtypes of monocytes and of lymphocytes were determined after staining with monoclonal antibodies and analysis by flow cytometry. Peripheral blood mononuclear cells (PBMCs were isolated from patients and stimulated with various bacterial stimuli. Concentrations of tumour necrosis factor-alpha, interleukin (IL-1beta, IL-6, IL-18, interferon (FN-alpha and of IFN-gamma were estimated in supernatants by an enzyme immunoassay. Infection by H1N1 was accompanied by an increase of monocytes. PBMCs of patients evoked strong cytokine production after stimulation with most of bacterial stimuli. Defective cytokine responses were shown in response to stimulation with phytohemagglutin and with heat-killed Streptococcus pneumoniae. Adaptive immune responses of H1N1-infected patients were characterized by decreases of CD4-lymphocytes and of B-lymphocytes and by increase of T-regulatory lymphocytes (Tregs. CONCLUSIONS/SIGNIFICANCE: Infection by the H1N1 virus is accompanied by a characteristic impairment of the innate immune responses characterized by defective cytokine responses to S.pneumoniae. Alterations of the adaptive immune responses are predominated by increase of Tregs. These findings signify a predisposition for pneumococcal infections after infection by H1N1 influenza.

Effect of the novel influenza A (H1N1) virus in the human immune system.

Science.gov (United States)

Giamarellos-Bourboulis, Evangelos J; Raftogiannis, Maria; Antonopoulou, Anastasia; Baziaka, Fotini; Koutoukas, Pantelis; Savva, Athina; Kanni, Theodora; Georgitsi, Marianna; Pistiki, Aikaterini; Tsaganos, Thomas; Pelekanos, Nikolaos; Athanassia, Sofia; Galani, Labrini; Giannitsioti, Efthymia; Kavatha, Dimitra; Kontopidou, Flora; Mouktaroudi, Maria; Poulakou, Garyfallia; Sakka, Vissaria; Panagopoulos, Periklis; Papadopoulos, Antonios; Kanellakopoulou, Kyriaki; Giamarellou, Helen

2009-12-23

The pandemic by the novel H1N1 virus has created the need to study any probable effects of that infection in the immune system of the host. Blood was sampled within the first two days of the presentation of signs of infection from 10 healthy volunteers; from 18 cases of flu-like syndrome; and from 31 cases of infection by H1N1 confirmed by reverse RT-PCR. Absolute counts of subtypes of monocytes and of lymphocytes were determined after staining with monoclonal antibodies and analysis by flow cytometry. Peripheral blood mononuclear cells (PBMCs) were isolated from patients and stimulated with various bacterial stimuli. Concentrations of tumour necrosis factor-alpha, interleukin (IL)-1beta, IL-6, IL-18, interferon (FN)-alpha and of IFN-gamma were estimated in supernatants by an enzyme immunoassay. Infection by H1N1 was accompanied by an increase of monocytes. PBMCs of patients evoked strong cytokine production after stimulation with most of bacterial stimuli. Defective cytokine responses were shown in response to stimulation with phytohemagglutin and with heat-killed Streptococcus pneumoniae. Adaptive immune responses of H1N1-infected patients were characterized by decreases of CD4-lymphocytes and of B-lymphocytes and by increase of T-regulatory lymphocytes (Tregs). Infection by the H1N1 virus is accompanied by a characteristic impairment of the innate immune responses characterized by defective cytokine responses to S.pneumoniae. Alterations of the adaptive immune responses are predominated by increase of Tregs. These findings signify a predisposition for pneumococcal infections after infection by H1N1 influenza.

Cross-protection against European swine influenza viruses in the context of infection immunity against the 2009 pandemic H1N1 virus: studies in the pig model of influenza.

Science.gov (United States)

Qiu, Yu; De Hert, Karl; Van Reeth, Kristien

2015-09-24

Pigs are natural hosts for the same influenza virus subtypes as humans and are a valuable model for cross-protection studies with influenza. In this study, we have used the pig model to examine the extent of virological protection between a) the 2009 pandemic H1N1 (pH1N1) virus and three different European H1 swine influenza virus (SIV) lineages, and b) these H1 viruses and a European H3N2 SIV. Pigs were inoculated intranasally with representative strains of each virus lineage with 6- and 17-week intervals between H1 inoculations and between H1 and H3 inoculations, respectively. Virus titers in nasal swabs and/or tissues of the respiratory tract were determined after each inoculation. There was substantial though differing cross-protection between pH1N1 and other H1 viruses, which was directly correlated with the relatedness in the viral hemagglutinin (HA) and neuraminidase (NA) proteins. Cross-protection against H3N2 was almost complete in pigs with immunity against H1N2, but was weak in H1N1/pH1N1-immune pigs. In conclusion, infection with a live, wild type influenza virus may offer substantial cross-lineage protection against viruses of the same HA and/or NA subtype. True heterosubtypic protection, in contrast, appears to be minimal in natural influenza virus hosts. We discuss our findings in the light of the zoonotic and pandemic risks of SIVs.

Genetics Home Reference: common variable immune deficiency

Science.gov (United States)

... disorders are immune thrombocytopenia purpura, which is an abnormal bleeding disorder caused by a decrease in cell fragments involved ... antibodies makes it difficult for people with this disorder to fight off infections. Abnormal and deficient immune responses over time likely contribute ...

Engineering Molecular Immunity Against Plant Viruses

KAUST Repository

Zaidi, Syed Shan-e-Ali; Tashkandi, Manal; Mahfouz, Magdy M.

2017-01-01

Genomic engineering has been used to precisely alter eukaryotic genomes at the single-base level for targeted gene editing, replacement, fusion, and mutagenesis, and plant viruses such as Tobacco rattle virus have been developed into efficient vectors for delivering genome-engineering reagents. In addition to altering the host genome, these methods can target pathogens to engineer molecular immunity. Indeed, recent studies have shown that clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) systems that target the genomes of DNA viruses can interfere with viral activity and limit viral symptoms in planta, demonstrating the utility of this system for engineering molecular immunity in plants. CRISPR/Cas9 can efficiently target single and multiple viral infections and confer plant immunity. Here, we discuss the use of site-specific nucleases to engineer molecular immunity against DNA and RNA viruses in plants. We also explore how to address the potential challenges encountered when producing plants with engineered resistance to single and mixed viral infections.

Engineering Molecular Immunity Against Plant Viruses

KAUST Repository

Zaidi, Syed Shan-e-Ali

2017-04-26

Genomic engineering has been used to precisely alter eukaryotic genomes at the single-base level for targeted gene editing, replacement, fusion, and mutagenesis, and plant viruses such as Tobacco rattle virus have been developed into efficient vectors for delivering genome-engineering reagents. In addition to altering the host genome, these methods can target pathogens to engineer molecular immunity. Indeed, recent studies have shown that clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) systems that target the genomes of DNA viruses can interfere with viral activity and limit viral symptoms in planta, demonstrating the utility of this system for engineering molecular immunity in plants. CRISPR/Cas9 can efficiently target single and multiple viral infections and confer plant immunity. Here, we discuss the use of site-specific nucleases to engineer molecular immunity against DNA and RNA viruses in plants. We also explore how to address the potential challenges encountered when producing plants with engineered resistance to single and mixed viral infections.

Detection of Immune-Complex Dissociated Nonstructural-1 (NS-1) Antigen in Patients with Acute Dengue Virus Infections

NARCIS (Netherlands)

P. Koraka (Penelope); C.P. Burghoorn-Maas; A. Falconar; T.E. Setiati (Tatty); K. Djamiatun; J. Groen (Jan); A.D.M.E. Osterhaus (Albert)

2003-01-01

textabstractAccurate and timely diagnosis of dengue virus (DEN) infections is essential for the differential diagnosis of patients with febrile illness and hemorrhagic fever. In the present study, the diagnostic value of a newly developed immune-complex dissociated nonstructural-1 (NS-1) antigen dot

Response of ELA-A1 horses immunized with lipopeptide containing an equine infectious anemia virus ELA-A1-restricted CTL epitope to virus challenge.

Science.gov (United States)

Ridgely, Sherritta L; Zhang, Baoshan; McGuire, Travis C

2003-01-17

Lipopeptide containing an ELA-A1-restricted cytotoxic T lymphocyte (CTL) epitope from the envelope surface unit (SU) protein of the EIAV(WSU5) strain was used to immunize three horses having the ELA-A1 haplotype. Peptide-specific ELA-A1-restricted CTL were induced in all three horses, although these were present transiently in PBMC. These horses were further immunized with lipopeptide containing the corresponding CTL epitope from the EIAV(PV) strain. Then, the three immunized horses and three non-immunized horses were challenged by intravenous inoculation with 300 TCID(50) EIAV(PV). All horses developed cell free viremia, fever and thrombocytopenia. However, there was a statistically lower fever and thrombocytopenia severity score in the immunized group. Shorter duration of plasma viral load in two of the three immunized horses likely explains the less severe clinical disease in this group. Results indicate that lipopeptide immunization had a protective effect against development of clinical disease following virus challenge.

Effects of Vector Backbone and Pseudotype on Lentiviral Vector-mediated Gene Transfer: Studies in Infant ADA-Deficient Mice and Rhesus Monkeys

Science.gov (United States)

Carbonaro Sarracino, Denise; Tarantal, Alice F; Lee, C Chang I.; Martinez, Michele; Jin, Xiangyang; Wang, Xiaoyan; Hardee, Cinnamon L; Geiger, Sabine; Kahl, Christoph A; Kohn, Donald B

2014-01-01

Systemic delivery of a lentiviral vector carrying a therapeutic gene represents a new treatment for monogenic disease. Previously, we have shown that transfer of the adenosine deaminase (ADA) cDNA in vivo rescues the lethal phenotype and reconstitutes immune function in ADA-deficient mice. In order to translate this approach to ADA-deficient severe combined immune deficiency patients, neonatal ADA-deficient mice and newborn rhesus monkeys were treated with species-matched and mismatched vectors and pseudotypes. We compared gene delivery by the HIV-1-based vector to murine γ-retroviral vectors pseudotyped with vesicular stomatitis virus-glycoprotein or murine retroviral envelopes in ADA-deficient mice. The vesicular stomatitis virus-glycoprotein pseudotyped lentiviral vectors had the highest titer and resulted in the highest vector copy number in multiple tissues, particularly liver and lung. In monkeys, HIV-1 or simian immunodeficiency virus vectors resulted in similar biodistribution in most tissues including bone marrow, spleen, liver, and lung. Simian immunodeficiency virus pseudotyped with the gibbon ape leukemia virus envelope produced 10- to 30-fold lower titers than the vesicular stomatitis virus-glycoprotein pseudotype, but had a similar tissue biodistribution and similar copy number in blood cells. The relative copy numbers achieved in mice and monkeys were similar when adjusted to the administered dose per kg. These results suggest that this approach can be scaled-up to clinical levels for treatment of ADA-deficient severe combined immune deficiency subjects with suboptimal hematopoietic stem cell transplantation options. PMID:24925206

Effects of vector backbone and pseudotype on lentiviral vector-mediated gene transfer: studies in infant ADA-deficient mice and rhesus monkeys.

Science.gov (United States)

Carbonaro Sarracino, Denise; Tarantal, Alice F; Lee, C Chang I; Martinez, Michele; Jin, Xiangyang; Wang, Xiaoyan; Hardee, Cinnamon L; Geiger, Sabine; Kahl, Christoph A; Kohn, Donald B

2014-10-01

Systemic delivery of a lentiviral vector carrying a therapeutic gene represents a new treatment for monogenic disease. Previously, we have shown that transfer of the adenosine deaminase (ADA) cDNA in vivo rescues the lethal phenotype and reconstitutes immune function in ADA-deficient mice. In order to translate this approach to ADA-deficient severe combined immune deficiency patients, neonatal ADA-deficient mice and newborn rhesus monkeys were treated with species-matched and mismatched vectors and pseudotypes. We compared gene delivery by the HIV-1-based vector to murine γ-retroviral vectors pseudotyped with vesicular stomatitis virus-glycoprotein or murine retroviral envelopes in ADA-deficient mice. The vesicular stomatitis virus-glycoprotein pseudotyped lentiviral vectors had the highest titer and resulted in the highest vector copy number in multiple tissues, particularly liver and lung. In monkeys, HIV-1 or simian immunodeficiency virus vectors resulted in similar biodistribution in most tissues including bone marrow, spleen, liver, and lung. Simian immunodeficiency virus pseudotyped with the gibbon ape leukemia virus envelope produced 10- to 30-fold lower titers than the vesicular stomatitis virus-glycoprotein pseudotype, but had a similar tissue biodistribution and similar copy number in blood cells. The relative copy numbers achieved in mice and monkeys were similar when adjusted to the administered dose per kg. These results suggest that this approach can be scaled-up to clinical levels for treatment of ADA-deficient severe combined immune deficiency subjects with suboptimal hematopoietic stem cell transplantation options.

Immunity to VHS virus in rainbow trout

DEFF Research Database (Denmark)

Lorenzen, Niels; Olesen, Niels Jørgen; Koch, C.

1999-01-01

Viral hemorrhagic septicemia virus (VHSV) is the rhabdovirus that causes most disease problems in farmed rainbow trout in Europe. Survivors of infection are usually immune to reinfection but as with other fish viruses, development of a modern recombinant vaccine has been complicated by the limited...... knowledge of the immune mechanisms and antigens involved in induction of immunity. Neutralizing and protective monoclonal antibodies recognize the envelope glycoprotein (G protein) which is the only viral protein known to be present on the surface of the virus particle. Immunoblotting analyses...... with monoclonal antibodies as well as with sera from immunized trout have indicated that protein conformation plays an important role in neutralization epitopes. The virus neutralizing activity often found in sera from convalescent trout is highly dependent on a poorly defined complementing activity in normal...

TREX1 deficiency triggers cell-autonomous immunity in a cGAS-dependent manner.

Science.gov (United States)

Ablasser, Andrea; Hemmerling, Inga; Schmid-Burgk, Jonathan L; Behrendt, Rayk; Roers, Axel; Hornung, Veit

2014-06-15

Cytosolic detection of DNA is crucial for the initiation of antiviral immunity but can also cause autoimmunity in the context of endogenous nucleic acids being sensed. Mutations in the human 3' repair exonuclease 1 (TREX1) have been linked to the type I IFN-associated autoimmune disease Aicardi-Goutières syndrome. The exact mechanisms driving unabated type I IFN responses in the absence of TREX1 are only partly understood, but it appears likely that accumulation of endogenous DNA species triggers a cell-autonomous immune response by activating a cytosolic DNA receptor. In this article, we demonstrate that knocking out the DNA sensor cyclic GMP-AMP synthase completely abrogates spontaneous induction of IFN-stimulated genes in TREX1-deficient cells. These findings indicate a key role of cyclic GMP-AMP synthase for the initiation of self-DNA-induced autoimmune disorders, thus providing important implications for novel therapeutic approaches. Copyright © 2014 by The American Association of Immunologists, Inc.

MAdCAM-1 expressing sacral lymph node in the lymphotoxin beta-deficient mouse provides a site for immune generation following vaginal herpes simplex virus-2 infection.

Science.gov (United States)

Soderberg, Kelly A; Linehan, Melissa M; Ruddle, Nancy H; Iwasaki, Akiko

2004-08-01

The members of the lymphotoxin (LT) family of molecules play a critical role in lymphoid organogenesis. Whereas LT alpha-deficient mice lack all lymph nodes and Peyer's patches, mice deficient in LT beta retain mesenteric lymph nodes and cervical lymph nodes, suggesting that an LT beta-independent pathway exists for the generation of mucosal lymph nodes. In this study, we describe the presence of a lymph node in LT beta-deficient mice responsible for draining the genital mucosa. In the majority of LT beta-deficient mice, a lymph node was found near the iliac artery, slightly misplaced from the site of the sacral lymph node in wild-type mice. The sacral lymph node of the LT beta-deficient mice, as well as that of the wild-type mice, expressed the mucosal addressin cell adhesion molecule-1 similar to the mesenteric lymph node. Following intravaginal infection with HSV type 2, activated dendritic cells capable of stimulating a Th1 response were found in this sacral lymph node. Furthermore, normal HSV-2-specific IgG responses were generated in the LT beta-deficient mice following intravaginal HSV-2 infection even in the absence of the spleen. Therefore, an LT beta-independent pathway exists for the development of a lymph node associated with the genital mucosa, and such a lymph node serves to generate potent immune responses against viral challenge.

Combined immunodeficiency and Epstein-Barr virus-induced B cell malignancy in humans with inherited CD70 deficiency

DEFF Research Database (Denmark)

Abolhassani, Hassan; Edwards, Emily S. J.; Ikinciogullari, Aydan

2017-01-01

In this study, we describe four patients from two unrelated families of different ethnicities with a primary immunodeficiency, predominantly manifesting as susceptibility to Epstein-Barr virus (EBV)-related diseases. Three patients presented with EBV-associated Hodgkin's lymphoma...... is a novel cause of combined immunodeficiency and EBV-associated diseases, reminiscent of inherited CD27 deficiency. Overall, human CD70-CD27 interactions therefore play a nonredundant role in T and B cell-mediated immunity, especially for protection against EBV and humoral immunity....

Homologous recombination deficiency and host anti-tumor immunity in triple-negative breast cancer.

Science.gov (United States)

Telli, M L; Stover, D G; Loi, S; Aparicio, S; Carey, L A; Domchek, S M; Newman, L; Sledge, G W; Winer, E P

2018-05-07

Triple-negative breast cancer (TNBC) is associated with worse outcomes relative to other breast cancer subtypes. Chemotherapy remains the standard-of-care systemic therapy for patients with localized or metastatic disease, with few biomarkers to guide benefit. We will discuss recent advances in our understanding of two key biological processes in TNBC, homologous recombination (HR) DNA repair deficiency and host anti-tumor immunity, and their intersection. Recent advances in our understanding of homologous recombination (HR) deficiency, including FDA approval of PARP inhibitor olaparib for BRCA1 or BRCA2 mutation carriers, and host anti-tumor immunity in TNBC offer potential for new and biomarker-driven approaches to treat TNBC. Assays interrogating HR DNA repair capacity may guide treatment with agents inducing or targeting DNA damage repair. Tumor infiltrating lymphocytes (TILs) are associated with improved prognosis in TNBC and recent efforts to characterize infiltrating immune cell subsets and activate host anti-tumor immunity offer promise, yet challenges remain particularly in tumors lacking pre-existing immune infiltrates. Advances in these fields provide potential biomarkers to stratify patients with TNBC and guide therapy: induction of DNA damage in HR-deficient tumors and activation of existing or recruitment of host anti-tumor immune cells. Importantly, these advances provide an opportunity to guide use of existing therapies and development of novel therapies for TNBC. Efforts to combine therapies that exploit HR deficiency to enhance the activity of immune-directed therapies offer promise. HR deficiency remains an important biomarker target and potentially effective adjunct to enhance immunogenicity of 'immune cold' TNBCs.

Vitamin D and neonatal immune function.

LENUS (Irish Health Repository)

Clancy, N

2013-05-01

Vitamin D deficiency is widespread in the neonatal and paediatric population of northern latitudes, particularly in children of African, Middle Eastern and Asian ethnicity. This is associated with diminished immune function and increases the risk of Th1 autoimmune diseases like type 1 diabetes. Epidermiological studies have also shown a link between vitamin D deficiency in children and a more severe course of illness with lower respiratory tract infection or Respiratory Syncitial Virus (RSV) bronchiolitis. The mechanism by which vitamin D enhances immunity is complex. It acts through the innate immune system by inducing antimicrobial peptides in epithelial cells, neutrophils and macrophages. The role of Vitamin D in neonatal and paediatric immunomodulation requires further study.

An update on the association of vitamin D deficiency with common infectious diseases.

Science.gov (United States)

Watkins, Richard R; Lemonovich, Tracy L; Salata, Robert A

2015-05-01

Vitamin D plays an important role in modulating the immune response to infections. Deficiency of vitamin D is a common condition, affecting both the general population and patients in health care facilities. Over the last decade, an increasing body of evidence has shown an association between vitamin D deficiency and an increased risk for acquiring several infectious diseases, as well as poorer outcomes in vitamin D deficient patients with infections. This review details recent developments in understanding the role of vitamin D in immunity, the antibacterial actions of vitamin D, the association between vitamin D deficiency and common infections (like sepsis, pneumonia, influenza, methicillin-resistant Staphylococcus aureus, human immunodeficiency virus type-1 (HIV), and hepatitis C virus (HCV)), potential therapeutic implications for vitamin D replacement, and future research directions.

A pandemic influenza H1N1 live vaccine based on modified vaccinia Ankara is highly immunogenic and protects mice in active and passive immunizations.

Directory of Open Access Journals (Sweden)

Annett Hessel

Full Text Available BACKGROUND: The development of novel influenza vaccines inducing a broad immune response is an important objective. The aim of this study was to evaluate live vaccines which induce both strong humoral and cell-mediated immune responses against the novel human pandemic H1N1 influenza virus, and to show protection in a lethal animal challenge model. METHODOLOGY/PRINCIPAL FINDINGS: For this purpose, the hemagglutinin (HA and neuraminidase (NA genes of the influenza A/California/07/2009 (H1N1 strain (CA/07 were inserted into the replication-deficient modified vaccinia Ankara (MVA virus--a safe poxviral live vector--resulting in MVA-H1-Ca and MVA-N1-Ca vectors. These live vaccines, together with an inactivated whole virus vaccine, were assessed in a lung infection model using immune competent Balb/c mice, and in a lethal challenge model using severe combined immunodeficient (SCID mice after passive serum transfer from immunized mice. Balb/c mice vaccinated with the MVA-H1-Ca virus or the inactivated vaccine were fully protected from lung infection after challenge with the influenza H1N1 wild-type strain, while the neuraminidase virus MVA-N1-Ca induced only partial protection. The live vaccines were already protective after a single dose and induced substantial amounts of neutralizing antibodies and of interferon-gamma-secreting (IFN-gamma CD4- and CD8 T-cells in lungs and spleens. In the lungs, a rapid increase of HA-specific CD4- and CD8 T cells was observed in vaccinated mice shortly after challenge with influenza swine flu virus, which probably contributes to the strong inhibition of pulmonary viral replication observed. In addition, passive transfer of antisera raised in MVA-H1-Ca vaccinated immune-competent mice protected SCID mice from lethal challenge with the CA/07 wild-type virus. CONCLUSIONS/SIGNIFICANCE: The non-replicating MVA-based H1N1 live vaccines induce a broad protective immune response and are promising vaccine candidates for

MVA-based H5N1 vaccine affords cross-clade protection in mice against influenza A/H5N1 viruses at low doses and after single immunization.

Directory of Open Access Journals (Sweden)

Joost H C M Kreijtz

Full Text Available Human infections with highly pathogenic avian influenza viruses of the H5N1 subtype, frequently reported since 2003, result in high morbidity and mortality. It is feared that these viruses become pandemic, therefore the development of safe and effective vaccines is desirable. MVA-based H5N1 vaccines already proved to be effective when two immunizations with high doses were used. Dose-sparing strategies would increase the number of people that can be vaccinated when the amount of vaccine preparations that can be produced is limited. Furthermore, protective immunity is induced ideally after a single immunization. Therefore the minimal requirements for induction of protective immunity with a MVA-based H5N1 vaccine were assessed in mice. To this end, mice were vaccinated once or twice with descending doses of a recombinant MVA expressing the HA gene of influenza virus A/Vietnam/1194/04. The protective efficacy was determined after challenge infection with the homologous clade 1 virus and a heterologous virus derived from clade 2.1, A/Indonesia/5/05 by assessing weight loss, virus replication and histopathological changes. It was concluded that MVA-based vaccines allowed significant dose-sparing and afford cross-clade protection, also after a single immunization, which are favorable properties for an H5N1 vaccine candidate.

Inducible nitric-oxide synthase plays a minimal role in lymphocytic choriomeningitis virus-induced, T cell-mediated protective immunity and immunopathology

DEFF Research Database (Denmark)

Bartholdy, C; Nansen, A; Christensen, Jeanette Erbo

1999-01-01

-mediated immune response was found to be unaltered in iNOS-deficient mice compared with wild-type C57BL/6 mice, and LCMV- induced general immunosuppression was equally pronounced in both strains. In vivo analysis revealed identical kinetics of virus clearance, as well as unaltered clinical severity of systemic......By using mice with a targetted disruption in the gene encoding inducible nitric-oxide synthase (iNOS), we have studied the role of nitric oxide (NO) in lymphocytic choriomeningitis virus (LCMV)-induced, T cell-mediated protective immunity and immunopathology. The afferent phase of the T cell...... LCMV infection in both strains. Concerning the outcome of intracerebral infection, no significant differences were found between iNOS-deficient and wild-type mice in the number or composition of mononuclear cells found in the cerebrospinal fluid on day 6 post-infection. Likewise, NO did not influence...

Virus-like particle vaccine primes immune responses preventing inactivated-virus vaccine-enhanced disease against respiratory syncytial virus.

Science.gov (United States)

Hwang, Hye Suk; Lee, Young-Tae; Kim, Ki-Hye; Ko, Eun-Ju; Lee, Youri; Kwon, Young-Man; Kang, Sang-Moo

2017-11-01

Formalin inactivated respiratory syncytial virus (FI-RSV) vaccination caused vaccine-enhanced respiratory disease (ERD) upon exposure to RSV in children. Virus-like particles presenting RSV F fusion protein (F VLP) are known to increase T helper type-1 (Th1) immune responses and avoid ERD in animal models. We hypothesized that F VLP would prime immune responses preventing ERD upon subsequent exposure to ERD-prone FI-RSV. Here, we demonstrated that heterologous F VLP priming and FI-RSV boosting of mice prevented FI-RSV vaccine-enhanced lung inflammation and eosinophilia upon RSV challenge. F VLP priming redirected pulmonary T cells toward effector CD8 T cells producing Th1 cytokines and significantly suppressed pulmonary Th2 cytokines. This study suggests that RSV F VLP priming would modulate and shift immune responses to subsequent exposure to ERD-prone FI-RSV vaccine and RSV infection, suppressing Th2 immune-mediated pulmonary histopathology and eosinophilia. Copyright © 2017. Published by Elsevier Inc.

Efficacy of genital T cell responses to herpes simplex virus type 2 resulting from immunization of the nasal mucosa

International Nuclear Information System (INIS)

Milligan, Gregg N.; Dudley-McClain, Kristen L.; Chu Chinfun; Young, Christal G.

2004-01-01

Intravaginal (ivag) or intranasal (i.n.) immunization of C57BL/6J (B6) mice with a thymidine kinase-deficient strain (tk-) of herpes simplex virus type 2 (HSV-2) resulted in comparable protection of the genital epithelium and sensory ganglia against HSV-2 challenge. In contrast, protection of these sites was much reduced in i.n.-immunized compared to ivag-immunized B cell-deficient μMT mice. Fewer HSV-specific T cells were detected in the genital epithelium of i.n.-immunized compared to ivag-immunized μMT mice after HSV-2 challenge. Passive transfer of HSV-specific serum to immune μMT mice restored protection of these sites against HSV-2 challenge. These results suggest that protection of genital and neuronal sites may be conferred by i.n. immunization but may be more dependent on antibody-dependent mechanisms than the protection resulting from genital immunization. These results have implications for immunization strategies to elicit high levels of cell-mediated protection of the genital tract and sensory ganglia

Human Ebola virus infection results in substantial immune activation.

Science.gov (United States)

McElroy, Anita K; Akondy, Rama S; Davis, Carl W; Ellebedy, Ali H; Mehta, Aneesh K; Kraft, Colleen S; Lyon, G Marshall; Ribner, Bruce S; Varkey, Jay; Sidney, John; Sette, Alessandro; Campbell, Shelley; Ströher, Ute; Damon, Inger; Nichol, Stuart T; Spiropoulou, Christina F; Ahmed, Rafi

2015-04-14

Four Ebola patients received care at Emory University Hospital, presenting a unique opportunity to examine the cellular immune responses during acute Ebola virus infection. We found striking activation of both B and T cells in all four patients. Plasmablast frequencies were 10-50% of B cells, compared with less than 1% in healthy individuals. Many of these proliferating plasmablasts were IgG-positive, and this finding coincided with the presence of Ebola virus-specific IgG in the serum. Activated CD4 T cells ranged from 5 to 30%, compared with 1-2% in healthy controls. The most pronounced responses were seen in CD8 T cells, with over 50% of the CD8 T cells expressing markers of activation and proliferation. Taken together, these results suggest that all four patients developed robust immune responses during the acute phase of Ebola virus infection, a finding that would not have been predicted based on our current assumptions about the highly immunosuppressive nature of Ebola virus. Also, quite surprisingly, we found sustained immune activation after the virus was cleared from the plasma, observed most strikingly in the persistence of activated CD8 T cells, even 1 mo after the patients' discharge from the hospital. These results suggest continued antigen stimulation after resolution of the disease. From these convalescent time points, we identified CD4 and CD8 T-cell responses to several Ebola virus proteins, most notably the viral nucleoprotein. Knowledge of the viral proteins targeted by T cells during natural infection should be useful in designing vaccines against Ebola virus.

Tuberculosis and the acquired immune deficiency syndrome in South Brazil

International Nuclear Information System (INIS)

Vieira, M.V.; Genro, C.H.; Santos Silveira, R. de C. dos

1989-01-01

Tuberculosis and the acquired immune deficiency syndrome in South Brazil. The authors studied the incidence of tuberculosis in South Brazilian patients with acquired immune deficiency syndrome from January 1985 to June 1988. During this period, tuberculosis occurred in 10.3% of acquired immune deficiency syndrome patients. The socioeconomic conditions and the incidence of disease in the population were not confirmed as a potential risk for tuberculosis infection. Chest radiographs revealed pulmonary infiltrates in six patients, hilar and/or mediastinal adenopathy in three, and pleural effusion in two. The two remaining patients had pulmonary consolidation associated with other features. None of these patients presented pulmonary cavitation or radiographic findings of typical reactivation of pulmonary tuberculosis. (author) [pt

Detection of immune-complex-dissociated nonstructural-1 antigen in patients with acute dengue virus infections

NARCIS (Netherlands)

P. Koraka (Penelope); C.P. Burghoorn-Maas; A. Falconar; T.E. Setiati (Tatty); K. Djamiatun; J. Groen (Jan); A.D.M.E. Osterhaus (Albert)

2003-01-01

textabstractAccurate and timely diagnosis of dengue virus (DEN) infections is essential for the differential diagnosis of patients with febrile illness and hemorrhagic fever. In the present study, the diagnostic value of a newly developed immune-complex dissociated nonstructural-1 (NS-1) antigen dot

Detection of immune-complex-dissociated nonstructural-1 antigen in patients with acute dengue virus infections.

NARCIS (Netherlands)

Koraka, P.; Burghoorn-Maas, C.P.; Falconar, A.; Setiati, T.E.; Djamiatun, K.; Groen, J.; Osterhaus, A.D.

2003-01-01

Accurate and timely diagnosis of dengue virus (DEN) infections is essential for the differential diagnosis of patients with febrile illness and hemorrhagic fever. In the present study, the diagnostic value of a newly developed immune-complex dissociated nonstructural-1 (NS-1) antigen dot blot

Flexible use of CCR5 in the absence of CXCR4 use explains the immune deficiency in HIV-1 infected children.

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Cavarelli, Mariangela; Karlsson, Ingrid; Ripamonti, Chiara; Plebani, Anna; Fenyo, Eva Maria; Scarlatti, Gabriella

2010-10-23

CCR5-using HIV-1 (R5 viruses) are usually isolated during acute infection from both adults and children. We have recently demonstrated that R5 viruses with a flexible use of CCR5 (called R5broad) can be detected in children close to birth and are predictive of a fast immunological failure. The aim of the present work was to investigate viral phenotype variation during disease progression in HIV-1 infected children, six slow and eight fast progressors. A total of 74 viral isolates obtained sequentially from 14 HIV-1 infected children were tested for their ability to infect U87.CD4 cells expressing a set of six different CCR5/CXCR4 chimeric receptors or wild-type coreceptors. The sensitivity of 35 R5 viruses to inhibition with the CC-chemokine RANTES (regulated upon activation, normal T-cell expressed and secreted) was evaluated in a peripheral blood mononuclear cells based assay. Viral evolution to R5broad or to R5X4 phenotype occurred with one exception, in all children, although at a different time point according to rate of disease progression. Immune deficiency in the children was significantly associated with the appearance of R5broad phenotype or R5X4 viruses. Analysis of the sensitivity to inhibition by RANTES revealed a significant correlation between the R5broad phenotype and an augmented resistance to this CC-chemokine. We demonstrate that the viral evolution to a more flexible CCR5-use is sufficient to explain the immunological failure in the absence of CXCR4 usage. These results warrant detailed analysis of the R5 phenotype in forthcoming clinical studies introducing CCR5 inhibitors for the treatment of pediatric HIV-1 infection.

Induction of influenza-specific mucosal immunity by an attenuated recombinant Sendai virus.

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Thuc-vy L Le

2011-04-01

Full Text Available Many pathogens initiate infection at the mucosal surfaces; therefore, induction of mucosal immune responses is a first level of defense against infection and is the most powerful means of protection. Although intramuscular injection is widely used for vaccination and is effective at inducing circulating antibodies, it is less effective at inducing mucosal antibodies.Here we report a novel recombinant, attenuated Sendai virus vector (GP42-H1 in which the hemagglutinin (HA gene of influenza A virus was introduced into the Sendai virus genome as an additional gene. Infection of CV-1 cells by GP42-H1 resulted in cell surface expression of the HA protein. Intranasal immunization of mice with 1,000 plaque forming units (pfu of GP42-H1 induced HA-specific IgG and IgA antibodies in the blood, bronchoalveolar lavage fluid, fecal pellet extracts and saliva. The HA-specific antibody titer induced by GP42-H1 closely resembles the titer induced by sublethal infection by live influenza virus; however, in contrast to infection by influenza virus, immunization with GP42-H1 did not result in disease symptoms or the loss of body weight. In mice that were immunized with GP42-H1 and then challenged with 5LD(50 (1250 pfu of influenza virus, no significant weight loss was observed and other visual signs of morbidity were not detected.These results demonstrate that the GP42-H1 Sendai virus recombinant is able to confer full protection from lethal infection by influenza virus, supporting the conclusion that it is a safe and effective mucosal vaccine vector.

Induction of long-term protective immune responses by influenza H5N1 virus-like particles.

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Sang-Moo Kang

Full Text Available Recurrent outbreaks of highly pathogenic H5N1 avian influenza virus pose a threat of eventually causing a pandemic. Early vaccination of the population would be the single most effective measure for the control of an emerging influenza pandemic.Influenza virus-like particles (VLPs produced in insect cell-culture substrates do not depend on the availability of fertile eggs for vaccine manufacturing. We produced VLPs containing influenza A/Viet Nam1203/04 (H5N1 hemagglutinin, neuraminidase, and matrix proteins, and investigated their preclinical immunogenicity and protective efficacy. Mice immunized intranasally with H5N1 VLPs developed high levels of H5N1 specific antibodies and were 100% protected against a high dose of homologous H5N1 virus infection at 30 weeks after immunization. Protection is likely to be correlated with humoral and cellular immunologic memory at systemic and mucosal sites as evidenced by rapid anamnestic responses to re-stimulation with viral antigen in vivo and in vitro.These results provide support for clinical evaluation of H5N1 VLP vaccination as a public health intervention to mitigate a possible pandemic of H5N1 influenza.

Linear DNA vaccine prepared by large-scale PCR provides protective immunity against H1N1 influenza virus infection in mice.

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Wang, Fei; Chen, Quanjiao; Li, Shuntang; Zhang, Chenyao; Li, Shanshan; Liu, Min; Mei, Kun; Li, Chunhua; Ma, Lixin; Yu, Xiaolan

2017-06-01

Linear DNA vaccines provide effective vaccination. However, their application is limited by high cost and small scale of the conventional polymerase chain reaction (PCR) generally used to obtain sufficient amounts of DNA effective against epidemic diseases. In this study, a two-step, large-scale PCR was established using a low-cost DNA polymerase, RKOD, expressed in Pichia pastoris. Two linear DNA vaccines encoding influenza H1N1 hemagglutinin (HA) 1, LEC-HA, and PTO-LEC-HA (with phosphorothioate-modified primers), were produced by the two-step PCR. Protective effects of the vaccines were evaluated in a mouse model. BALB/c mice were immunized three times with the vaccines or a control DNA fragment. All immunized animals were challenged by intranasal administration of a lethal dose of influenza H1N1 virus 2 weeks after the last immunization. Sera of the immunized animals were tested for the presence of HA-specific antibodies, and the total IFN-γ responses induced by linear DNA vaccines were measured. The results showed that the DNA vaccines but not the control DNA induced strong antibody and IFN-γ responses. Additionally, the PTO-LEC-HA vaccine effectively protected the mice against the lethal homologous mouse-adapted virus, with a survival rate of 100% versus 70% in the LEC-HA-vaccinated group, showing that the PTO-LEC-HA vaccine was more effective than LEC-HA. In conclusion, the results indicated that the linear H1N1 HA-coding DNA vaccines induced significant immune responses and protected mice against a lethal virus challenge. Thus, the low-cost, two-step, large-scale PCR can be considered a potential tool for rapid manufacturing of linear DNA vaccines against emerging infectious diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

Cellular immune responses to respiratory viruses

NARCIS (Netherlands)

van Helden, M.J.G.

2011-01-01

When a respiratory virus successfully infects the lungs, cascades of immune responses are initiated aimed to remove the pathogen. Immediate non-specific protection is provided by the innate immune system and this reduces the viral load during the first days of infection. The adaptive immune response

Adenosine Deaminase (ADA)-Deficient Severe Combined Immune Deficiency (SCID): Molecular Pathogenesis and Clinical Manifestations.

Science.gov (United States)

Bradford, Kathryn L; Moretti, Federico A; Carbonaro-Sarracino, Denise A; Gaspar, Hubert B; Kohn, Donald B

2017-10-01

Deficiency of adenosine deaminase (ADA, EC3.5.4.4), a housekeeping enzyme of purine metabolism encoded by the Ada gene, is a cause of human severe combined immune deficiency (SCID). Numerous deleterious mutations occurring in the ADA gene have been found in patients with profound lymphopenia (T - B - NK - ), thus underscoring the importance of functional purine metabolism for the development of the immune defense. While untreated ADA SCID is a fatal disorder, there are multiple life-saving therapeutic modalities to restore ADA activity and reconstitute protective immunity, including enzyme replacement therapy (ERT), allogeneic hematopoietic stem cell transplantation (HSCT) and gene therapy (GT) with autologous gene-corrected hematopoietic stem cells (HSC). We review the pathogenic mechanisms and clinical manifestations of ADA SCID.

Induction of protective immunity in swine by recombinant bamboo mosaic virus expressing foot-and-mouth disease virus epitopes

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Lin Na-Sheng

2007-09-01

Full Text Available Abstract Background Plant viruses can be employed as versatile vectors for the production of vaccines by expressing immunogenic epitopes on the surface of chimeric viral particles. Although several viruses, including tobacco mosaic virus, potato virus X and cowpea mosaic virus, have been developed as vectors, we aimed to develop a new viral vaccine delivery system, a bamboo mosaic virus (BaMV, that would carry larger transgene loads, and generate better immunity in the target animals with fewer adverse environmental effects. Methods We engineered the BaMV as a vaccine vector expressing the antigenic epitope(s of the capsid protein VP1 of foot-and-mouth disease virus (FMDV. The recombinant BaMV plasmid (pBVP1 was constructed by replacing DNA encoding the 35 N-terminal amino acid residues of the BaMV coat protein with that encoding 37 amino acid residues (T128-N164 of FMDV VP1. Results The pBVP1 was able to infect host plants and to generate a chimeric virion BVP1 expressing VP1 epitopes in its coat protein. Inoculation of swine with BVP1 virions resulted in the production of anti-FMDV neutralizing antibodies. Real-time PCR analysis of peripheral blood mononuclear cells from the BVP1-immunized swine revealed that they produced VP1-specific IFN-γ. Furthermore, all BVP1-immunized swine were protected against FMDV challenge. Conclusion Chimeric BaMV virions that express partial sequence of FMDV VP1 can effectively induce not only humoral and cell-mediated immune responses but also full protection against FMDV in target animals. This BaMV-based vector technology may be applied to other vaccines that require correct expression of antigens on chimeric viral particles.

Genetics Home Reference: purine nucleoside phosphorylase deficiency

Science.gov (United States)

... the expand/collapse boxes. Description Purine nucleoside phosphorylase deficiency is one of several disorders that damage the immune system and cause severe combined immunodeficiency (SCID). People with SCID lack virtually all immune protection from foreign invaders such as bacteria, viruses, and ...

Immune Evasion by Epstein-Barr Virus.

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Ressing, Maaike E; van Gent, Michiel; Gram, Anna M; Hooykaas, Marjolein J G; Piersma, Sytse J; Wiertz, Emmanuel J H J

2015-01-01

Epstein-Bar virus (EBV) is widespread within the human population with over 90% of adults being infected. In response to primary EBV infection, the host mounts an antiviral immune response comprising both innate and adaptive effector functions. Although the immune system can control EBV infection to a large extent, the virus is not cleared. Instead, EBV establishes a latent infection in B lymphocytes characterized by limited viral gene expression. For the production of new viral progeny, EBV reactivates from these latently infected cells. During the productive phase of infection, a repertoire of over 80 EBV gene products is expressed, presenting a vast number of viral antigens to the primed immune system. In particular the EBV-specific CD4+ and CD8+ memory T lymphocytes can respond within hours, potentially destroying the virus-producing cells before viral replication is completed and viral particles have been released. Preceding the adaptive immune response, potent innate immune mechanisms provide a first line of defense during primary and recurrent infections. In spite of this broad range of antiviral immune effector mechanisms, EBV persists for life and continues to replicate. Studies performed over the past decades have revealed a wide array of viral gene products interfering with both innate and adaptive immunity. These include EBV-encoded proteins as well as small noncoding RNAs with immune-evasive properties. The current review presents an overview of the evasion strategies that are employed by EBV to facilitate immune escape during latency and productive infection. These evasion mechanisms may also compromise the elimination of EBV-transformed cells, and thus contribute to malignancies associated with EBV infection.

Inactivated Recombinant Rabies Viruses Displaying Canine Distemper Virus Glycoproteins Induce Protective Immunity against Both Pathogens.

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da Fontoura Budaszewski, Renata; Hudacek, Andrew; Sawatsky, Bevan; Krämer, Beate; Yin, Xiangping; Schnell, Matthias J; von Messling, Veronika

2017-04-15

The development of multivalent vaccines is an attractive methodology for the simultaneous prevention of several infectious diseases in vulnerable populations. Both canine distemper virus (CDV) and rabies virus (RABV) cause lethal disease in wild and domestic carnivores. While RABV vaccines are inactivated, the live-attenuated CDV vaccines retain residual virulence for highly susceptible wildlife species. In this study, we developed recombinant bivalent vaccine candidates based on recombinant vaccine strain rabies virus particles, which concurrently display the protective CDV and RABV glycoprotein antigens. The recombinant viruses replicated to near-wild-type titers, and the heterologous glycoproteins were efficiently expressed and incorporated in the viral particles. Immunization of ferrets with beta-propiolactone-inactivated recombinant virus particles elicited protective RABV antibody titers, and animals immunized with a combination of CDV attachment protein- and fusion protein-expressing recombinant viruses were protected from lethal CDV challenge. However, animals that were immunized with only a RABV expressing the attachment protein of CDV vaccine strain Onderstepoort succumbed to infection with a more recent wild-type strain, indicating that immune responses to the more conserved fusion protein contribute to protection against heterologous CDV strains. IMPORTANCE Rabies virus and canine distemper virus (CDV) cause high mortality rates and death in many carnivores. While rabies vaccines are inactivated and thus have an excellent safety profile and high stability, live-attenuated CDV vaccines can retain residual virulence in highly susceptible species. Here we generated recombinant inactivated rabies viruses that carry one of the CDV glycoproteins on their surface. Ferrets immunized twice with a mix of recombinant rabies viruses carrying the CDV fusion and attachment glycoproteins were protected from lethal CDV challenge, whereas all animals that received

Filovirus pathogenesis and immune evasion: insights from Ebola virus and Marburg virus

Energy Technology Data Exchange (ETDEWEB)

Messaoudi, Ilhem; Amarasinghe, Gaya K.; Basler, Christopher F.

2015-10-06

Ebola viruses and Marburg viruses, members of the filovirus family, are zoonotic pathogens that cause severe disease in people, as highlighted by the latest Ebola virus epidemic in West Africa. Filovirus disease is characterized by uncontrolled virus replication and the activation of host responses that contribute to pathogenesis. Underlying these phenomena is the potent suppression of host innate antiviral responses, particularly the type I interferon response, by viral proteins, which allows high levels of viral replication. In this Review, we describe the mechanisms used by filoviruses to block host innate immunity and discuss the links between immune evasion and filovirus pathogenesis.

Primer for non-immunologists on immune-deficient mice and their applications in research.

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Croy, B A; Linder, K E; Yager, J A

2001-08-01

Studies of immune deficiencies have a history as long as that of immunology. However, reports of two key spontaneous recessive mutations in mice (nude in 1966-1968 and scid in 1983) laid the foundations for widespread application of immune-deficient rodents to a broad range of research topics. More recently, technologies modifying the mouse genome by transgenesis, gene ablation and crossbreeding for lines with multiple immune deficits have provided a large number of new types of immunologically impaired mice. The primary goals of this overview are to help non-immunologists understand key differences between some of the immunodeficient strains, develop an appreciation for the value of information derived from immunodeficient mouse-based research and to encourage expanded, creative use of these specialized research animals. Secondary goals are to promote greater awareness of unexpected outcomes that can arise when working with genetically immune-deficient mice, the need for vigilance in maintaining these research animals, and the care required in interpretation of the data that immune-deficient modeling provides. Two illustrations on developing appropriate immune deficient animal models for a new research application conclude the review.

Deficient CD4+ T cell priming and regression of CD8+ T cell functionality in virus-infected mice lacking a normal B cell compartment

DEFF Research Database (Denmark)

Christensen, Jan Pravsgaard; Kauffmann, Susanne Ørding; Thomsen, Allan Randrup

2003-01-01

of virus-specific CD4(+) T cells was markedly impaired in B(-/-) mice infected with either virus strain. Thus, our results indicate that B cells play an important role in antiviral immunity not only as Ab producers, but also in promoting an optimal and sustained T cell response. The T cell defects......In this study, we investigate the state of T cell-mediated immunity in B cell-deficient (B(-/-)) mice infected with two strains of lymphocytic choriomeningitis virus known to differ markedly in their capacity to persist. In B(-/-) C57BL mice infected with the more persisting virus, virus......-specific CD8(+) T cells are initially generated that are qualitatively similar to those in wild-type mice. However, although cell numbers are well sustained over time, the capacity to produce cytokines is rapidly impaired. In similarly infected B(-/-) BALB/c mice, virus-specific CD8(+) T cells are completely...

Natural and adoptive T-cell immunity against herpes family viruses after allogeneic hematopoietic stem cell transplantation.

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Thomas, Simone; Herr, Wolfgang

2011-06-01

Reactivated infections with herpes family-related cytomegalovirus, Epstein-Barr virus and varicella zoster virus are serious and sometimes life-threatening complications for patients undergoing allogeneic hematopoietic stem cell transplantation. The pathogenesis of these infections critically involves the slow and inefficient recovery of antiviral T-cell immunity after transplantation. Although efficient drugs to decrease viral load during this vulnerable period have been developed, long-term control of herpes viruses and protection from associated diseases require the sufficient reconstitution of virus-specific memory T cells. To heal the deficiency by immunotherapeutic means, numerous research groups have developed antiviral vaccines and strategies based on the adoptive transfer of virus-specific T cells. This article summarizes the substantial progress made in this field during the past two decades and gives future perspectives about challenges that need to be addressed before antigen-specific immunotherapy against herpes family viruses can be implemented in general clinical practice.

Capturing public interest toward new tools for controlling human immunodeficiency virus (HIV) infection exploiting data from Google Trends.

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Mahroum, Naim; Bragazzi, Nicola Luigi; Brigo, Francesco; Waknin, Roy; Sharif, Kassem; Mahagna, Hussein; Amital, Howard; Watad, Abdulla

2018-04-01

Human immunodeficiency virus vaccination and pre-exposure prophylaxis represent two different emerging preventive tools. Google Trends was used to assess the public interest toward these tools in terms of digital activities. Worldwide web searches concerning the human immunodeficiency virus vaccine represented 0.34 percent, 0.03 percent, and 46.97 percent of human immunodeficiency virus, acquired immune deficiency syndrome, and human immunodeficiency virus/acquired immune deficiency syndrome treatment-related Google Trends queries, respectively. Concerning temporal trends, digital activities were shown to increase from 0 percent as of 1 January 2004 percent to 46 percent as of 8 October 2017 with two spikes observed in May and July 2012, coinciding with the US Food and Drug Administration approval. Bursts in search number and volume were recorded as human immunodeficiency virus vaccine trials emerged. This search topic has decreased in the past decade in parallel to the increase in Truvada-related topics. Concentrated searches were noticed among African countries with high human immunodeficiency virus/acquired immune deficiency syndrome prevalence. Stakeholders should take advantage of public interest especially in preventive medicine in high disease burden countries.

Knowledge, attitude, and behavioral practices pertaining to human immunodeficiency virus/acquired immune deficiency syndrome among secondary school adolescents in makurdi, Nigeria

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Ayu Agbecha

2017-01-01

Full Text Available Background: Adolescents knowledge with their safe practices pertaining to human immunodeficiency virus (HIV has a critical impact on the prevention of contracting and spreading HIV. Reports have shown that adolescents in the general setting engage in activities that enhance the spread of the virus. Aim: The study assessed school adolescent's HIV/acquired immune deficiency syndrome (AIDS knowledge, with its impact on their behaviors and attitudes regarding the infection. Materials and Methods: Two hundred randomly selected adolescent students from 10 different schools in the city metropolis were involved in the cross-sectional study. Primary data were collected using a validated self-administered questionnaire on students HIV/AIDS knowledge, attitude toward people living with HIV/AIDS (PLWHA, and safe practices preventing the spread of HIV/AIDS. Results: The study observed that majority of the students had good knowledge about HIV/AIDS, had good attitude toward PLWHA, and engaged in safe practices that prevent the spread of HIV. The sources of HIV/AIDS information were hospital, school, home, electronic, and print media. The study also found that HIV/AIDS knowledge instilled good attitudes and behavioral practices in the students. Conclusion: The study shows that school sex education, as well as health promotion campaigns through media platforms, could impact positively on the knowledge, attitude, and behavioral practices of adolescents in curbing the spread of HIV/AIDS.

Immune responses of poultry to Newcastle disease virus.

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Kapczynski, Darrell R; Afonso, Claudio L; Miller, Patti J

2013-11-01

Newcastle disease (ND) remains a constant threat to poultry producers worldwide, in spite of the availability and global employment of ND vaccinations since the 1950s. Strains of Newcastle disease virus (NDV) belong to the order Mononegavirales, family Paramyxoviridae, and genus Avulavirus, are contained in one serotype and are also known as avian paramyxovirus serotype-1 (APMV-1). They are pleomorphic in shape and are single-stranded, non-segmented, negative sense RNA viruses. The virus has been reported to infect most orders of birds and thus has a wide host range. Isolates are characterized by virulence in chickens and the presence of basic amino acids at the fusion protein cleavage site. Low virulent NDV typically produce subclinical disease with some morbidity, whereas virulent isolates can result in rapid, high mortality of birds. Virulent NDV are listed pathogens that require immediate notification to the Office of International Epizootics and outbreaks typically result in trade embargos. Protection against NDV is through the use of vaccines generated with low virulent NDV strains. Immunity is derived from neutralizing antibodies formed against the viral hemagglutinin and fusion glycoproteins, which are responsible for attachment and spread of the virus. However, new techniques and technologies have also allowed for more in depth analysis of the innate and cell-mediated immunity of poultry to NDV. Gene profiling experiments have led to the discovery of novel host genes modulated immediately after infection. Differences in virus virulence alter host gene response patterns have been demonstrated. Furthermore, the timing and contributions of cell-mediated immune responses appear to decrease disease and transmission potential. In view of recent reports of vaccine failure from many countries on the ability of classical NDV vaccines to stop spread of disease, renewed interest in a more complete understanding of the global immune response of poultry to NDV will be

Intramuscular Immunization of Mice with the Live-Attenuated Herpes Simplex Virus 1 Vaccine Strain VC2 Expressing Equine Herpesvirus 1 (EHV-1) Glycoprotein D Generates Anti-EHV-1 Immune Responses in Mice.

Science.gov (United States)

Liu, Shiliang A; Stanfield, Brent A; Chouljenko, Vladimir N; Naidu, Shan; Langohr, Ingeborg; Del Piero, Fabio; Ferracone, Jacqueline; Roy, Alma A; Kousoulas, Konstantin G

2017-06-15

Vaccination remains the best option to combat equine herpesvirus 1 (EHV-1) infection, and several different strategies of vaccination have been investigated and developed over the past few decades. Herein, we report that the live-attenuated herpes simplex virus 1 (HSV-1) VC2 vaccine strain, which has been shown to be unable to enter into neurons and establish latency in mice, can be utilized as a vector for the heterologous expression of EHV-1 glycoprotein D (gD) and that the intramuscular immunization of mice results in strong antiviral humoral and cellular immune responses. The VC2-EHV-1-gD recombinant virus was constructed by inserting an EHV-1 gD expression cassette under the control of the cytomegalovirus immediate early promoter into the VC2 vector in place of the HSV-1 thymidine kinase (UL23) gene. The vaccines were introduced into mice through intramuscular injection. Vaccination with both the VC2-EHV-1-gD vaccine and the commercially available vaccine Vetera EHV XP 1/4 (Vetera; Boehringer Ingelheim Vetmedica) resulted in the production of neutralizing antibodies, the levels of which were significantly higher in comparison to those in VC2- and mock-vaccinated animals ( P < 0.01 or P < 0.001). Analysis of EHV-1-reactive IgG subtypes demonstrated that vaccination with the VC2-EHV-1-gD vaccine stimulated robust IgG1 and IgG2a antibodies after three vaccinations ( P < 0.001). Interestingly, Vetera-vaccinated mice produced significantly higher levels of IgM than mice in the other groups before and after challenge ( P < 0.01 or P < 0.05). Vaccination with VC2-EHV-1-gD stimulated strong cellular immune responses, characterized by the upregulation of both interferon- and tumor necrosis factor-positive CD4 + T cells and CD8 + T cells. Overall, the data suggest that the HSV-1 VC2 vaccine strain may be used as a viral vector for the vaccination of horses as well as, potentially, for the vaccination of other economically important animals. IMPORTANCE A novel virus

Adaptive immunity and histopathology in frog virus 3-infected Xenopus

International Nuclear Information System (INIS)

Robert, Jacques; Morales, Heidi; Buck, Wayne; Cohen, Nicholas; Marr, Shauna; Gantress, Jennifer

2005-01-01

Xenopus has been used as an experimental model to evaluate the contribution of adaptive cellular immunity in amphibian host susceptibility to the emerging ranavirus FV3. Conventional histology and immunohistochemistry reveal that FV3 has a strong tropism for the proximal tubular epithelium of the kidney and is rarely disseminated elsewhere in Xenopus hosts unless their immune defenses are impaired or developmentally immature as in larvae. In such cases, virus is found widespread in most tissues. Adults, immunocompromised by depletion of CD8 + T cells or by sub-lethal γ-irradiation, show increased susceptibility to FV3 infection. Larvae and irradiated (but not normal) adults can be cross-infected through water by infected adult conspecifics (irradiated or not). The natural MHC class I deficiency and the absence of effect of anti-CD8 treatment on both larval CD8 + T cells and larval susceptibility to FV3 are consistent with an inefficient CD8 + T cell effector function during this developmental period

Primary Immune Deficiency Treatment Consortium (PIDTC) report

NARCIS (Netherlands)

L.M. Griffith (Linda); M. Cowan (Morton); L.D. Notarangelo (Luigi Daniele); R. Kohn (Robert); J. Puck (Jennifer); S.-Y. Pai (Sung-Yun); B. Ballard (Barbara); S.C. Bauer (Sarah); J. Bleesing (Jack); M. Boyle (Marcia); R.W. Brower (Ronald); R.H. Buckley (Rebecca); M. van der Burg (Mirjam); L.M. Burroughs (Lauri); F. Candotti (Fabio); A. Cant (Andrew); T. Chatila (Talal); C. Cunningham-Rundles (Charlotte); M.C. Dinauer (Mary); J. Dvorak (Jennie); A. Filipovich (Alexandra); L.A. Fleisher (Lee); H.B. Gaspar (Bobby); T. Gungor (Tayfun); E. Haddad (Elie); E. Hovermale (Emily); F. Huang (Faith); A. Hurley (Alan); M. Hurley (Mary); S.K. Iyengar (Sudha); E.M. Kang (Elizabeth); B.R. Logan (Brent); J.R. Long-Boyle (Janel); H. Malech (Harry); S.A. McGhee (Sean); S. Modell (Sieglinde); S. Modell (Sieglinde); H.D. Ochs (Hans); R.J. O'Reilly (Richard); R. Parkman (Robertson); D. Rawlings (D.); J.M. Routes (John); P. Shearer (P.); T.N. Small (Trudy); H. Smith (H.); K.E. Sullivan (Kathleen); P. Szabolcs (Paul); A.J. Thrasher (Adrian); D. Torgerson; P. Veys (Paul); K. Weinberg (Kenneth); J.C. Zuniga-Pflucker (Juan Carlos)

2014-01-01

textabstractThe Primary Immune Deficiency Treatment Consortium (PIDTC) is a network of 33 centers in North America that study the treatment of rare and severe primary immunodeficiency diseases. Current protocols address the natural history of patients treated for severe combined immunodeficiency

Hepatitis B and C Sero-prevalence in Patients with Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome at a Tertiary Care Hospital in Izmir

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Sabri ATALAY

2018-04-01

Full Text Available Objectives: Infections caused by human immunodeficiency virus (HIV, hepatitis B virus (HBV and hepatitis C virus (HCV represent a significant health problem. Co-infection with these viral agents is not uncommon as a result of the similar transmission routes. Our study was planned to investigate the prevalence of HBV and HCV infections in HIV/Acquired Immune Deficiency syndrome (AIDS patients followed up at our institution. Materials and Methods: In this study conducted in the Department of Infectious Diseases and Clinical Microbiology at Izmir Tepecik Training and Research Hospital, medical records of patients followed at the HIV/AIDS outpatient clinic between August 2002 and December 2014 were evaluated. Demographic data, main route of HIV transmission, hepatitis B surface antigen (HBsAg, anti-hepatitis B core (HBc immunoglobulin G (IgG, anti-HBs and anti-HCV results were evaluated. Results: A total of 157 treatment-naïve patients who were followed up at our HIV/AIDS outpatient clinic were included in this study. Four patients (2.6%, had HBsAg positivity. Anti-HBc IgG and anti-HBs positivity were detected in 34% and 28.4% of the patients, respectively. No patients had anti-HCV positivity. Conclusion: The prevalence of HBsAg in HIV-positive individuals was found to be similar to that in other population-based studies in our country. Absence of anti-HCV positivity suggests that hepatitis C infection is not a major health problem in this population.

Immune Evasion by Epstein-Barr Virus

NARCIS (Netherlands)

Ressing, Maaike E; van Gent, Michiel; Gram, Anna M; Hooykaas, Marjolein J G; Piersma, Sytse J; Wiertz, EJHJ

2015-01-01

Epstein-Bar virus (EBV) is widespread within the human population with over 90% of adults being infected. In response to primary EBV infection, the host mounts an antiviral immune response comprising both innate and adaptive effector functions. Although the immune system can control EBV infection to

Acute immune thrombocytopenic purpura in an adolescent with 2009 novel H1N1 influenza A virus infection

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Chun-Yi Lee

2011-09-01

Full Text Available Although both leukopenia and thrombocytopenia are not uncommon hematological findings among patients with novel 2009 H1N1 influenza virus infection, immune thrombocytopenic purpura has rarely been shown to be associated with this novel influenza A infection. Here, we describe a previously healthy adolescent who presented with fever, influenza-like symptoms and acute onset of generalized petechiae and active oral mucosa bleeding on the third day of his illness. Severe leukopenia and thrombocytopenia were found. There was neither malignancy nor blast cells found by bone marrow aspiration. Real-time reverse transcriptase polymerase chain reaction was positive for novel 2009 H1N1 influenza infection. Novel influenza-associated atypical immune thrombocytopenic purpura was diagnosed. The patient recovered uneventfully after oseltamivir and methylprednisolone therapy.

Immune barriers of Ebola virus infection.

Science.gov (United States)

McElroy, Anita K; Mühlberger, Elke; Muñoz-Fontela, César

2018-02-01

Since its initial emergence in 1976 in northern Democratic Republic of Congo (DRC), Ebola virus (EBOV) has been a global health concern due to its virulence in humans, the mystery surrounding the identity of its host reservoir and the unpredictable nature of Ebola virus disease (EVD) outbreaks. Early after the first clinical descriptions of a disease resembling a 'septic-shock-like syndrome', with coagulation abnormalities and multi-system organ failure, researchers began to evaluate the role of the host immune response in EVD pathophysiology. In this review, we summarize how data gathered during the last 40 years in the laboratory as well as in the field have provided insight into EBOV immunity. From molecular mechanisms involved in EBOV recognition in infected cells, to antigen processing and adaptive immune responses, we discuss current knowledge on the main immune barriers of infection as well as outstanding research questions. Copyright © 2018 Elsevier B.V. All rights reserved.

Influenza H5N1 and H1N1 virus replication and innate immune responses in bronchial epithelial cells are influenced by the state of differentiation.

Directory of Open Access Journals (Sweden)

Renee W Y Chan

Full Text Available Influenza H5N1 virus continues to be enzootic in poultry and transmits zoonotically to humans. Although a swine-origin H1N1 virus has emerged to become pandemic, its virulence for humans remains modest in comparison to that seen in zoonotic H5N1 disease. As human respiratory epithelium is the primary target cells for influenza viruses, elucidating the viral tropism and host innate immune responses of influenza H5N1 virus in human bronchial epithelium may help to understand the pathogenesis. Here we established primary culture of undifferentiated and well differentiated normal human bronchial epithelial (NHBE cells and infected with highly pathogenic influenza H5N1 virus (A/Vietnam/3046/2004 and a seasonal influenza H1N1 virus (A/Hong Kong/54/1998, the viral replication kinetics and cytokine and chemokine responses were compared by qPCR and ELISA. We found that the in vitro culture of the well differentiated NHBE cells acquired the physiological properties of normal human bronchi tissue which express high level of alpha2-6-linked sialic acid receptors and human airway trypsin-like (HAT protease, in contrast to the low expression in the non-differentiated NHBE cells. When compared to H1N1 virus, the H5N1 virus replicated more efficiently and induced a stronger type I interferon response in the undifferentiated NHBE cells. In contrast, in well differentiated cultures, H5N1 virus replication was less efficient and elicited a lower interferon-beta response in comparison with H1N1 virus. Our data suggest that the differentiation of bronchial epithelial cells has a major influence in cells' permissiveness to human H1N1 and avian H5N1 viruses and the host innate immune responses. The reduced virus replication efficiency partially accounts for the lower interferon-beta responses in influenza H5N1 virus infected well differentiated NHBE cells. Since influenza infection in the bronchial epithelium will lead to tissue damage and associate with the

Priming-boosting vaccination with recombinant Mycobacterium bovis bacillus Calmette-Guérin and a nonreplicating vaccinia virus recombinant leads to long-lasting and effective immunity.

Science.gov (United States)

Ami, Yasushi; Izumi, Yasuyuki; Matsuo, Kazuhiro; Someya, Kenji; Kanekiyo, Masaru; Horibata, Shigeo; Yoshino, Naoto; Sakai, Koji; Shinohara, Katsuaki; Matsumoto, Sohkichi; Yamada, Takeshi; Yamazaki, Shudo; Yamamoto, Naoki; Honda, Mitsuo

2005-10-01

Virus-specific T-cell responses can limit immunodeficiency virus type 1 (HIV-1) transmission and prevent disease progression and so could serve as the basis for an affordable, safe, and effective vaccine in humans. To assess their potential for a vaccine, we used Mycobacterium bovis bacillus Calmette-Guérin (BCG)-Tokyo and a replication-deficient vaccinia virus strain (DIs) as vectors to express full-length gag from simian immunodeficiency viruses (SIVs) (rBCG-SIVgag and rDIsSIVgag). Cynomolgus macaques were vaccinated with either rBCG-SIVgag dermally as a single modality or in combination with rDIsSIVgag intravenously. When cynomologus macaques were primed with rBCG-SIVgag and then boosted with rDIsSIVgag, high levels of gamma interferon (IFN-gamma) spot-forming cells specific for SIV Gag were induced. This combination regimen elicited effective protective immunity against mucosal challenge with pathogenic simian-human immunodeficiency virus for the 1 year the macaques were under observation. Antigen-specific intracellular IFN-gamma activity was similarly induced in each of the macaques with the priming-boosting regimen. Other groups receiving the opposite combination or the single-modality vaccines were not effectively protected. These results suggest that a recombinant M. bovis BCG-based vector may have potential as an HIV/AIDS vaccine when administered in combination with a replication-deficient vaccinia virus DIs vector in a priming-boosting strategy.

Immune responses to influenza virus and its correlation to age and inherited factors

Directory of Open Access Journals (Sweden)

Azadeh Bahadoran

2016-11-01

Full Text Available Influenza viruses belong to the family Orthomyxoviridae of enveloped viruses and are an important cause of respiratory infections worldwide. The influenza virus is able to infect a wide variety species as diverse as poultry, marine, pigs, horses and humans. Upon infection with influenza virus the innate immunity plays a critical role in efficient and rapid control of viral infections as well as in adaptive immunity initiation. The humoral immune system produces antibodies against different influenza antigens, of which the HA-specific antibody is the most important for neutralization of the virus and thus prevention of illness. Cell mediated immunity including CD4+ helper T cells and CD8+ cytotoxic T cells are the other arms of adaptive immunity induced upon influenza virus infection. The complex inherited factors and age related changes are associated with the host immune responses. Here, we review the different components of immune responses against influenza virus. Additionally, the correlation of the immune response to age and inherited factors has been discussed. These determinations lead to a better understanding of the limitations of immune responses for developing improved vaccines to control influenza virus infection.

Pandemic influenza 1918 H1N1 and 1968 H3N2 DNA vaccines induce cross-reactive immunity in ferrets against infection with viruses drifted for decades

DEFF Research Database (Denmark)

Bragstad, Karoline; Martel, Cyril; Thomsen, Joakim S.

2011-01-01

Please cite this paper as: Bragstad et al. (2010) Pandemic influenza 1918 H1N1 and 1968 H3N2 DNA vaccines induce cross-reactive immunity in ferrets against infection with viruses drifted for decades. Influenza and Other Respiratory Viruses 5(1), 13-23. Background Alternative influenza vaccines...... and vaccine production forms are needed as the conventional protein vaccines do not induce broad cross-reactivity against drifted strains. Furthermore, fast vaccine production is especially important in a pandemic situation, and broader vaccine reactivity would diminish the need for frequent change...... in the vaccine formulations. Objective In this study, we compared the ability of pandemic influenza DNA vaccines to induce immunity against distantly related strains within a subtype with the immunity induced by conventional trivalent protein vaccines against homologous virus challenge. Methods Ferrets were...

Platelets in Immune Response to Virus and Immunopathology of Viral Infections

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Eugenio D. Hottz

2018-04-01

Full Text Available Platelets are essential effector cells in hemostasis. Aside from their role in coagulation, platelets are now recognized as major inflammatory cells with key roles in the innate and adaptive arms of the immune system. Activated platelets have key thromboinflammatory functions linking coagulation to immune responses in various infections, including in response to virus. Recent studies have revealed that platelets exhibit several pattern recognition receptors (PRR including those from the toll-like receptor, NOD-like receptor, and C-type lectin receptor family and are first-line sentinels in detecting and responding to pathogens in the vasculature. Here, we review the main mechanisms of platelets interaction with viruses, including their ability to sustain viral infection and replication, their expression of specialized PRR, and activation of thromboinflammatory responses against viruses. Finally, we discuss the role of platelet-derived mediators and platelet interaction with vascular and immune cells in protective and pathophysiologic responses to dengue, influenza, and human immunodeficiency virus 1 infections.

Modified vaccinia virus Ankara protects macaques against respiratory challenge with monkeypox virus.

NARCIS (Netherlands)

K.J. Stittelaar (Koert); G. van Amerongen (Geert); I. Kondova (Ivanela); R.F. van Lavieren (Rob); F.H. Pistoor (Frank); H.G.M. Niesters (Bert); G.J.J. van Doornum (Gerard); B.A.M. van der Zeijst (Ben); L. Mateo (Luis); P.J. Chaplin (Paul); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

2005-01-01

textabstractThe use of classical smallpox vaccines based on vaccinia virus (VV) is associated with severe complications in both naive and immune individuals. Modified vaccinia virus Ankara (MVA), a highly attenuated replication-deficient strain of VV, has been proven to be safe in humans and

Deficiency of the Chemotactic Factor Inactivator in Human Sera with α1-Antitrypsin Deficiency

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Ward, Peter A.; Talamo, Richard C.

1973-01-01

As revealed by appropriate fractionation procedures, human serum deficient in α1-antitrypsin (α1-AT) is also deficient in the naturally occurring chemotactic factor inactivator. These serum donors had severe pulmonary emphysema. Serum from patients with clinically similar pulmonary disease, but with presence of α1-AT in the serum, showed no such deficiency of the chemotactic factor inactivator. When normal human serum and α1-AT-deficient human sera are chemotactically activated by incubation with immune precipitates, substantially more chemotactic activity is generated in α1-AT-deficient serum. These data indicate that in α1-AT-deficient serum there is an imbalance in the generation and control of chemotactic factors. It is suggested that the theory regarding development of pulmonary emphysema in patients lacking the α1-antitrypsin in their serum should be modified to take into account a deficiency of the chemotactic factor inactivator. PMID:4683887

Cellular Immunity State of Protein-deficient Rats with the Toxic Liver Injury

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O.N. Voloshchuk

2017-05-01

Full Text Available Studies on the role of immunity mechanisms in the emergence and maintenance of inflammatory and destructive processes in the liver under toxic hepatitis and nutrient deficiency are topical. The aim of research – to study the quantitative content and functional activity of leukocytes under the conditions of acetaminophen-induced hepatitis on the background of nutritional protein deficiency. The most pronounced changes in cell-mediated immunity are observed in protein-deficient animals with toxic hepatitis. The pronounced defects of both specific and non-specific cellular immunity were manifested by the leukocytosis, increase number of segmented neutrophils in blood serum against decrease their phagocytic index and phagocytic number, reduction of total lymphocyte number, and simultaneously lowering of T- and B-lymphocytes was established under the conditions of acetaminophen-induced hepatotoxicity on the background of protein deficiency. Installed changes indicate the defective formation of functional immunity state which can manifest by decrease the body’s ability to carry out the reaction of cellular and humoral immunity. Research results may be used for the rationale of therapeutic approaches to the elimination and correction of the consequences of immunological status disturbances under the conditions of acetaminophen-induced hepatitis, aggravated by the alimentary protein deprivation.

M2e-displaying virus-like particles with associated RNA promote T helper 1 type adaptive immunity against influenza A.

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Lorena Itatí Ibañez

Full Text Available The ectodomain of influenza A matrix protein 2 (M2e is a candidate for a universal influenza A vaccine. We used recombinant Hepatitis B core antigen to produce virus-like particles presenting M2e (M2e-VLPs. We produced the VLPs with and without entrapped nucleic acids and compared their immunogenicity and protective efficacy. Immunization of BALB/c mice with M2e-VLPs containing nucleic acids induced a stronger, Th1-biased antibody response compared to particles lacking nucleic acids. The former also induced a stronger M2e-specific CD4(+ T cell response, as determined by ELISPOT. Mice vaccinated with alum-adjuvanted M2e-VLPs containing the nucleic acid-binding domain were better protected against influenza A virus challenge than mice vaccinated with similar particles lacking this domain, as deduced from the loss in body weight following challenge with X47 (H3N2 or PR/8 virus. Challenge of mice that had been immunized with M2e-VLPs with or without nucleic acids displayed significantly lower mortality, morbidity and lung virus titers than control-immunized groups. We conclude that nucleic acids present in M2e-VLPs correlate with improved immune protection.

Clinical and biological differences between recurrent herpes simplex virus and varicella-zoster virus infections

International Nuclear Information System (INIS)

Straus, S.E.

1989-01-01

The major features that distinguish recurrent herpes simplex virus infections from zoster are illustrated in this article by two case histories. The clinical and epidemiologic features that characterize recurrent herpes simplex virus and varicella-zoster virus infections are reviewed. It is noted that herpesvirus infections are more common and severe in patients with cellular immune deficiency. Each virus evokes both humoral and cellular immune response in the course of primary infection. DNA hybridization studies with RNA probes labelled with sulfur-35 indicate that herpes simplex viruses persist within neurons, and that varicella-zoster virus is found in the satellite cells that encircle the neurons

Prophylactic immunoglobulin therapy in secondary immune deficiency

DEFF Research Database (Denmark)

Agostini, Carlo; Blau, Igor-Wolfgang; Kimby, Eva

2016-01-01

RT in secondary immune deficiencies (SID), and most published guidelines are mere extrapolations from the experience in PID. AREAS COVERED: In this article, four European experts provide their consolidated opinion on open questions surrounding the prophylactic use of IgRT in SID, based on their clinical...

Replication-deficient mutant Herpes Simplex Virus-1 targets professional antigen presenting cells and induces efficient CD4+ T helper responses.

OpenAIRE

Fiorentini, Simona; Marconi, Peggy; Avolio, Manuela; Marini, Elena; Garrafa, Emirena; Caracciolo, Sonia; Rossi, Daniele; Bozac, Alexandra; Becker, Pablo D; Gentili, Francesca; Facchetti, Fabio; Guzman, Carlos A; Manservigi, Roberto; Caruso, Arnaldo

2007-01-01

Both neutralizing antibodies and cytotoxic T-cells are necessary to control a viral infection. However, vigorous T helper responses are essential for their elicitation and maintenance. Here we show that a recombinant replication-deficient Herpes Simplex Virus (HSV)-1 vector encoding the Human Immunodeficiency Virus (HIV)-1 matrix protein p17 (T0-p17) was capable of infecting professional antigen presenting cells (APCs) in vitro and in vivo. The injection of T0-p17 in the mouse dermis generate...

Virus-like particles displaying H5, H7, H9 hemagglutinins and N1 neuraminidase elicit protective immunity to heterologous avian influenza viruses in chickens

International Nuclear Information System (INIS)

Pushko, Peter; Tretyakova, Irina; Hidajat, Rachmat; Zsak, Aniko; Chrzastek, Klaudia; Tumpey, Terrence M.; Kapczynski, Darrell R.

2017-01-01

Avian influenza (AI) viruses circulating in wild birds pose a serious threat to public health. Human and veterinary vaccines against AI subtypes are needed. Here we prepared triple-subtype VLPs that co-localized H5, H7 and H9 antigens derived from H5N1, H7N3 and H9N2 viruses. VLPs also contained influenza N1 neuraminidase and retroviral gag protein. The H5/H7/H9/N1/gag VLPs were prepared using baculovirus expression. Biochemical, functional and antigenic characteristics were determined including hemagglutination and neuraminidase enzyme activities. VLPs were further evaluated in a chicken AI challenge model for safety, immunogenicity and protective efficacy against heterologous AI viruses including H5N2, H7N3 and H9N2 subtypes. All vaccinated birds survived challenges with H5N2 and H7N3 highly pathogenic AI (HPAI) viruses, while all controls died. Immune response was also detectable after challenge with low pathogenicity AI (LPAI) H9N2 virus suggesting that H5/H7/H9/N1/gag VLPs represent a promising approach for the development of broadly protective AI vaccine. - Highlights: •VLPs were prepared that co-localized H5, H7 and H9 subtypes in a VLP envelope. •VLPs were characterized including electron microscopy, HA assay and NA enzyme activity. •Experimental VLP vaccine was evaluated in an avian influenza challenge model. •VLPs induced immune responses against heterologous H5, H7 and H9 virus challenges.

Virus-like particles displaying H5, H7, H9 hemagglutinins and N1 neuraminidase elicit protective immunity to heterologous avian influenza viruses in chickens

Energy Technology Data Exchange (ETDEWEB)

Pushko, Peter, E-mail: ppushko@medigen-usa.com [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States); Tretyakova, Irina; Hidajat, Rachmat [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States); Zsak, Aniko; Chrzastek, Klaudia [USDA SEPRL, 934 College Station Rd, Athens, GA (United States); Tumpey, Terrence M. [Influenza Division, CDC,1600 Clifton Road N.E., Atlanta, GA (United States); Kapczynski, Darrell R. [USDA SEPRL, 934 College Station Rd, Athens, GA (United States)

2017-01-15

Avian influenza (AI) viruses circulating in wild birds pose a serious threat to public health. Human and veterinary vaccines against AI subtypes are needed. Here we prepared triple-subtype VLPs that co-localized H5, H7 and H9 antigens derived from H5N1, H7N3 and H9N2 viruses. VLPs also contained influenza N1 neuraminidase and retroviral gag protein. The H5/H7/H9/N1/gag VLPs were prepared using baculovirus expression. Biochemical, functional and antigenic characteristics were determined including hemagglutination and neuraminidase enzyme activities. VLPs were further evaluated in a chicken AI challenge model for safety, immunogenicity and protective efficacy against heterologous AI viruses including H5N2, H7N3 and H9N2 subtypes. All vaccinated birds survived challenges with H5N2 and H7N3 highly pathogenic AI (HPAI) viruses, while all controls died. Immune response was also detectable after challenge with low pathogenicity AI (LPAI) H9N2 virus suggesting that H5/H7/H9/N1/gag VLPs represent a promising approach for the development of broadly protective AI vaccine. - Highlights: •VLPs were prepared that co-localized H5, H7 and H9 subtypes in a VLP envelope. •VLPs were characterized including electron microscopy, HA assay and NA enzyme activity. •Experimental VLP vaccine was evaluated in an avian influenza challenge model. •VLPs induced immune responses against heterologous H5, H7 and H9 virus challenges.

Mechanisms of innate immune evasion in re-emerging RNA viruses.

Science.gov (United States)

Ma, Daphne Y; Suthar, Mehul S

2015-06-01

Recent outbreaks of Ebola, West Nile, Chikungunya, Middle Eastern Respiratory and other emerging/re-emerging RNA viruses continue to highlight the need to further understand the virus-host interactions that govern disease severity and infection outcome. As part of the early host antiviral defense, the innate immune system mediates pathogen recognition and initiation of potent antiviral programs that serve to limit virus replication, limit virus spread and activate adaptive immune responses. Concordantly, viral pathogens have evolved several strategies to counteract pathogen recognition and cell-intrinsic antiviral responses. In this review, we highlight the major mechanisms of innate immune evasion by emerging and re-emerging RNA viruses, focusing on pathogens that pose significant risk to public health. Copyright © 2015 Elsevier B.V. All rights reserved.

A20 (Tnfaip3 deficiency in myeloid cells protects against influenza A virus infection.

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Jonathan Maelfait

Full Text Available The innate immune response provides the first line of defense against viruses and other pathogens by responding to specific microbial molecules. Influenza A virus (IAV produces double-stranded RNA as an intermediate during the replication life cycle, which activates the intracellular pathogen recognition receptor RIG-I and induces the production of proinflammatory cytokines and antiviral interferon. Understanding the mechanisms that regulate innate immune responses to IAV and other viruses is of key importance to develop novel therapeutic strategies. Here we used myeloid cell specific A20 knockout mice to examine the role of the ubiquitin-editing protein A20 in the response of myeloid cells to IAV infection. A20 deficient macrophages were hyperresponsive to double stranded RNA and IAV infection, as illustrated by enhanced NF-κB and IRF3 activation, concomitant with increased production of proinflammatory cytokines, chemokines and type I interferon. In vivo this was associated with an increased number of alveolar macrophages and neutrophils in the lungs of IAV infected mice. Surprisingly, myeloid cell specific A20 knockout mice are protected against lethal IAV infection. These results challenge the general belief that an excessive host proinflammatory response is associated with IAV-induced lethality, and suggest that under certain conditions inhibition of A20 might be of interest in the management of IAV infections.

Late effects of atomic bomb radiation on human immune responses, (10); Results on studies of immune responses to EB-virus

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Kusunoki, Yoichiro; Kyoizumi, Seishi; Ozaki, Kyoko; Saito, Mayumi; Cologne, J.B.; Akiyama, Mitoshi (Radiation Effects Research Foundation, Hiroshima (Japan))

1992-12-01

Anti-Epstein-Barr (EV) virus antibody titers were measured in age- and sex-matched three groups of each 124 A-bomb survivors who had exposed to <0.01 Gy, 0.01-1 Gy, or >1 Gy. These serum samples showed positive antibodies against viral capsid antigens (VCA). Antibody titers to anti-VCA-IgM or anti-EA-IgG were significantly higher in the groups of 0.01-1 Gy and >1 Gy than in the group of <0.01 Gy, reflecting decreased immune response ability for EV virus. When precursor frequency of cytotoxic cells against autologous EB virus LCL was determined in 68 other A-bomb survivors, no definitive influence of A-bombing was observed. However, serological study revealed that there was inverse correlation between precursor frequency and anti-EA-IgG antibody titer. These findings suggest that the immune response ability for EB virus may have been damaged and that biological reactivity of EB virus may occur frequently in A-bomb survivors. (N.K.).

Early death after feline infectious peritonitis virus challenge due to recombinant vaccinia virus immunization.

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Vennema, H; de Groot, R J; Harbour, D A; Dalderup, M; Gruffydd-Jones, T; Horzinek, M C; Spaan, W J

1990-01-01

The gene encoding the fusogenic spike protein of the coronavirus causing feline infectious peritonitis was recombined into the genome of vaccinia virus. The recombinant induced spike-protein-specific, in vitro neutralizing antibodies in mice. When kittens were immunized with the recombinant, low titers of neutralizing antibodies were obtained. After challenge with feline infectious peritonitis virus, these animals succumbed earlier than did the control group immunized with wild-type vaccinia virus (early death syndrome). Images PMID:2154621

MALT1 Controls Attenuated Rabies Virus by Inducing Early Inflammation and T Cell Activation in the Brain.

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Kip, E; Staal, J; Verstrepen, L; Tima, H G; Terryn, S; Romano, M; Lemeire, K; Suin, V; Hamouda, A; Kalai, M; Beyaert, R; Van Gucht, S

2018-04-15

MALT1 is involved in the activation of immune responses, as well as in the proliferation and survival of certain cancer cells. MALT1 acts as a scaffold protein for NF-κB signaling and a cysteine protease that cleaves substrates, further promoting the expression of immunoregulatory genes. Deregulated MALT1 activity has been associated with autoimmunity and cancer, implicating MALT1 as a new therapeutic target. Although MALT1 deficiency has been shown to protect against experimental autoimmune encephalomyelitis, nothing is known about the impact of MALT1 on virus infection in the central nervous system. Here, we studied infection with an attenuated rabies virus, Evelyn-Rotnycki-Abelseth (ERA) virus, and observed increased susceptibility with ERA virus in MALT1 -/- mice. Indeed, after intranasal infection with ERA virus, wild-type mice developed mild transient clinical signs with recovery at 35 days postinoculation (dpi). Interestingly, MALT1 -/- mice developed severe disease requiring euthanasia at around 17 dpi. A decreased induction of inflammatory gene expression and cell infiltration and activation was observed in MALT1 -/- mice at 10 dpi compared to MALT1 +/+ infected mice. At 17 dpi, however, the level of inflammatory cell activation was comparable to that observed in MALT1 +/+ mice. Moreover, MALT1 -/- mice failed to produce virus-neutralizing antibodies. Similar results were obtained with specific inactivation of MALT1 in T cells. Finally, treatment of wild-type mice with mepazine, a MALT1 protease inhibitor, also led to mortality upon ERA virus infection. These data emphasize the importance of early inflammation and activation of T cells through MALT1 for controlling the virulence of an attenuated rabies virus in the brain. IMPORTANCE Rabies virus is a neurotropic virus which can infect any mammal. Annually, 59,000 people die from rabies. Effective therapy is lacking and hampered by gaps in the understanding of virus pathogenicity. MALT1 is an intracellular

Viral (hepatitis C virus, hepatitis B virus, HIV) persistence and immune homeostasis

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Zhou, Yun; Zhang, Ying; Moorman, Jonathan P; Yao, Zhi Q; Jia, Zhan S

2014-01-01

Immune homeostasis is a host characteristic that maintains biological balance within a host. Humans have evolved many host defence mechanisms that ensure the survival of individuals upon encountering a pathogenic infection, with recovery or persistence from a viral infection being determined by both viral factors and host immunity. Chronic viral infections, such as hepatitis B virus, hepatitis C virus and HIV, often result in chronic fluctuating viraemia in the face of host cellular and humoral immune responses, which are dysregulated by multi-faceted mechanisms that are incompletely understood. This review attempts to illuminate the mechanisms involved in this process, focusing on immune homeostasis in the setting of persistent viral infection from the aspects of host defence mechanism, including interferon-stimulated genes, apolipoprotein B mRNA editing enzyme catalytic polypeptide 3 (APOBEC3), autophagy and interactions of various immune cells, cytokines and regulatory molecules. PMID:24965611

Successful topical respiratory tract immunization of primates against Ebola virus.

Science.gov (United States)

Bukreyev, Alexander; Rollin, Pierre E; Tate, Mallory K; Yang, Lijuan; Zaki, Sherif R; Shieh, Wun-Ju; Murphy, Brian R; Collins, Peter L; Sanchez, Anthony

2007-06-01

Ebola virus causes outbreaks of severe viral hemorrhagic fever with high mortality in humans. The virus is highly contagious and can be transmitted by contact and by the aerosol route. These features make Ebola virus a potential weapon for bioterrorism and biological warfare. Therefore, a vaccine that induces both systemic and local immune responses in the respiratory tract would be highly beneficial. We evaluated a common pediatric respiratory pathogen, human parainfluenza virus type 3 (HPIV3), as a vaccine vector against Ebola virus. HPIV3 recombinants expressing the Ebola virus (Zaire species) surface glycoprotein (GP) alone or in combination with the nucleocapsid protein NP or with the cytokine adjuvant granulocyte-macrophage colony-stimulating factor were administered by the respiratory route to rhesus monkeys--in which HPIV3 infection is mild and asymptomatic--and were evaluated for immunogenicity and protective efficacy against a highly lethal intraperitoneal challenge with Ebola virus. A single immunization with any construct expressing GP was moderately immunogenic against Ebola virus and protected 88% of the animals against severe hemorrhagic fever and death caused by Ebola virus. Two doses were highly immunogenic, and all of the animals survived challenge and were free of signs of disease and of detectable Ebola virus challenge virus. These data illustrate the feasibility of immunization via the respiratory tract against the hemorrhagic fever caused by Ebola virus. To our knowledge, this is the first study in which topical immunization through respiratory tract achieved prevention of a viral hemorrhagic fever infection in a primate model.

In vivo Ebola virus infection leads to a strong innate response in circulating immune cells.

Science.gov (United States)

Caballero, Ignacio S; Honko, Anna N; Gire, Stephen K; Winnicki, Sarah M; Melé, Marta; Gerhardinger, Chiara; Lin, Aaron E; Rinn, John L; Sabeti, Pardis C; Hensley, Lisa E; Connor, John H

2016-09-05

Ebola virus is the causative agent of a severe syndrome in humans with a fatality rate that can approach 90 %. During infection, the host immune response is thought to become dysregulated, but the mechanisms through which this happens are not entirely understood. In this study, we analyze RNA sequencing data to determine the host response to Ebola virus infection in circulating immune cells. Approximately half of the 100 genes with the strongest early increases in expression were interferon-stimulated genes, such as ISG15, OAS1, IFIT2, HERC5, MX1 and DHX58. Other highly upregulated genes included cytokines CXCL11, CCL7, IL2RA, IL2R1, IL15RA, and CSF2RB, which have not been previously reported to change during Ebola virus infection. Comparing this response in two different models of exposure (intramuscular and aerosol) revealed a similar signature of infection. The strong innate response in the aerosol model was seen not only in circulating cells, but also in primary and secondary target tissues. Conversely, the innate immune response of vaccinated macaques was almost non-existent. This suggests that the innate response is a major aspect of the cellular response to Ebola virus infection in multiple tissues. Ebola virus causes a severe infection in humans that is associated with high mortality. The host immune response to virus infection is thought to be an important aspect leading to severe pathology, but the components of this overactive response are not well characterized. Here, we analyzed how circulating immune cells respond to the virus and found that there is a strong innate response dependent on active virus replication. This finding is in stark contrast to in vitro evidence showing a suppression of innate immune signaling, and it suggests that the strong innate response we observe in infected animals may be an important contributor to pathogenesis.

T Cell-Mediated Immunity towards Yellow Fever Virus and Useful Animal Models.

Science.gov (United States)

Watson, Alan M; Klimstra, William B

2017-04-11

The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus.

Antibody study in canine distemper virus nucleocapsid protein gene-immunized mice.

Science.gov (United States)

Yuan, B; Li, X Y; Zhu, T; Yuan, L; Hu, J P; Chen, J; Gao, W; Ren, W Z

2015-04-10

The gene for the nucleocapsid (N) protein of canine distemper virus was cloned into the pMD-18T vector, and positive recombinant plasmids were obtained by enzyme digestion and sequencing. After digestion by both EcoRI and KpnI, the plasmid was directionally cloned into the eukaryotic expression vector pcDNA; the positive clone pcDNA-N was screened by electrophoresis and then transfected into COS-7 cells. Immunofluorescence analysis results showed that the canine distemper virus N protein was expressed in the cytoplasm of transfected COS-7 cells. After emulsification in Freund's adjuvant, the recombinant plasmid pcDNA-N was injected into the abdominal cavity of 8-week-old BABL/c mice, with the pcDNA original vector used as a negative control. Mice were immunized 3 times every 2 weeks. The blood of immunized mice was drawn 2 weeks after completing the immunizations to measure titer levels. The antibody titer in the pcDNA-N test was 10(1.62 ± 0.164), while in the control group this value was 10(0.52 ± 0.56), indicating that specific humoral immunity was induced in canine distemper virus nucleocapsid protein-immunized mice.

Studies on the antibody response of mice and humans after immunization with potential influenza virus A (H1N1) vaccines

International Nuclear Information System (INIS)

Poumbourios, P.; Jackson, D.C.; Oxford, J.S.

1993-01-01

The antibody response of mice and adult humans to immunization with subunit vaccines derived from a pair of antigenically distinct influenza A H1N1 viruses isolate in eggs was investigated. Although the haemagglutinin molecule of each virus differed by only three amino acid residues, highly specific antibody responses were elicited in mice as determined by haemagglutination inhibition and radioimmunoprecipitation assays. Results from competitive radioimmunoassays using monoclonal antibodies of known specificity and a study of the reactivity of mouse antisera with H1N1 field strains indicated that the marked differences in the antibody responses to the two vaccines was due to an amino acid substitution in the distal tip of the haemagglutinin molecule. In contrast, cross reactive antibody responses were elicited in humans presumably due to exposure to viruses related to the candidate vaccine prior to vaccination. Although immunogenic differences are apparent in this pair of antigenically distinct viruses in naive laboratory animals, these differences are not apparent following vaccination of humans that had prior exposure to related viruses. 21 refs., 5 tabs., 4 figs

The Hayflick Limit and Age-Related Adaptive Immune Deficiency.

Science.gov (United States)

Gill, Zoe; Nieuwoudt, Martin; Ndifon, Wilfred

2018-01-01

The adaptive immune system (AIS) acquires significant deficiency during chronological ageing, making older individuals more susceptible to infections and less responsive to vaccines compared to younger individuals. At the cellular level, one of the most striking features of this ageing-related immune deficiency is the dramatic loss of T-cell diversity that occurs in elderly humans. After the age of 70 years, there is a sharp decline in the diversity of naïve T cells, including a >10-fold decrease in the CD4+ compartment and a >100-fold decrease in the CD8+ compartment. Such changes are detrimental because the AIS relies on a diverse naïve T-cell pool to respond to novel pathogens. Recent work suggests that this collapse of naïve T-cell diversity results from T cells reaching the Hayflick limit and being eliminated through both antigen-dependent and -independent pathways. The progressive attrition of telomeres is the molecular mechanism that underlies this Hayflick limit. Therefore, we propose that by measuring the telomere lengths of T cells with high resolution, it is possible to develop a unique biomarker of immune deficiency, potentially much better correlated with individual susceptibility to diseases compared to chronological age alone. © 2017 S. Karger AG, Basel.

Pseudoachondroplasia with immune deficiency

International Nuclear Information System (INIS)

Kultursay, N.; Taneli, B.; Cavusoglu, A.

1988-01-01

A 5-year old boy was admitted to the hospital with failure to thrive since he was 2 years old, with weakness in his legs and a waddling gait. He has normal mental development. His parents are normal phenotypically and are unrelated. In analysing his pedigree only a grandfather is described to have waddling gait. He has a normal craniofacial appearance but a disproportionate body with normal trunk and short extremities with height below the 3rd percentile. The diagnosis of pseudoachondroplasia was made on clinical, radiological and laboratory findings. He also had immune deficiency characterised by low T-lymphocyte populations and a low level of serum immunoglobulin A. (orig.)

Tumor Necrosis Factor-Mediated Survival of CD169+ Cells Promotes Immune Activation during Vesicular Stomatitis Virus Infection

DEFF Research Database (Denmark)

Shinde, Prashant V; Xu, Haifeng C; Maney, Sathish Kumar

2018-01-01

Innate immune activation is essential to mount an effective antiviral response and to prime adaptive immunity. Although a crucial role of CD169(+) cells during vesicular stomatitis virus (VSV) infections is increasingly recognized, factors regulating CD169(+) cells during viral infections remain...... stomatitis virus infection, phagocytes produce tumor necrosis factor (TNF) which signals via TNFR1 and promote "enforced virus replication" in CD169(+) macrophages. Consequently, lack of TNF or TNFR1 resulted in defective immune activation and VSV clearance....

Abnormal humoral immune response to influenza vaccination in pediatric type-1 human immunodeficiency virus infected patients receiving highly active antiretroviral therapy

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Carlos J Montoya

2007-06-01

Full Text Available Given that highly active antiretroviral therapy (HAART has been demonstrated useful to restore immune competence in type-1 human immunodeficiency virus (HIV-1-infected subjects, we evaluated the specific antibody response to influenza vaccine in a cohort of HIV-1-infected children on HAART so as to analyze the quality of this immune response in patients under antiretroviral therapy. Sixteen HIV-1-infected children and 10 HIV-1 seronegative controls were immunized with a commercially available trivalent inactivated influenza vaccine containing the strains A/H1N1, A/H3N2, and B. Serum hemagglutinin inhibition (HI antibody titers were determined for the three viral strains at the time of vaccination and 1 month later. Immunization induced a significantly increased humoral response against the three influenza virus strains in controls, and only against A/H3N2 in HIV-1-infected children. The comparison of post-vaccination HI titers between HIV-1+ patients and HIV-1 negative controls showed significantly higher HI titers against the three strains in controls. In addition, post vaccination protective HI titers (defined as equal to or higher than 1:40 against the strains A/H3N2 and B were observed in a lower proportion of HIV-1+ children than in controls, while a similar proportion of individuals from each group achieved protective HI titers against the A/H1N1 strain. The CD4+ T cell count, CD4/CD8 T cells ratio, and serum viral load were not affected by influenza virus vaccination when pre- vs post-vaccination values were compared. These findings suggest that despite the fact that HAART is efficient in controlling HIV-1 replication and in increasing CD4+ T cell count in HIV-1-infected children, restoration of immune competence and response to cognate antigens remain incomplete, indicating that additional therapeutic strategies are required to achieve a full reconstitution of immune functions.

Effect of Probiotic Bacteria on Microbial Host Defense, Growth, and Immune Function in Human Immunodeficiency Virus Type-1 Infection

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Stig Bengmark

2011-12-01

Full Text Available The hypothesis that probiotic administration protects the gut surface and could delay progression of Human Immunodeficiency Virus type1 (HIV-1 infection to the Acquired Immunodeficiency Syndrome (AIDS was proposed in 1995. Over the last five years, new studies have clarified the significance of HIV-1 infection of the gut associated lymphoid tissue (GALT for subsequent alterations in the microflora and breakdown of the gut mucosal barrier leading to pathogenesis and development of AIDS. Current studies show that loss of gut CD4+ Th17 cells, which differentiate in response to normal microflora, occurs early in HIV-1 disease. Microbial translocation and suppression of the T regulatory (Treg cell response is associated with chronic immune activation and inflammation. Combinations of probiotic bacteria which upregulate Treg activation have shown promise in suppressing pro inflammatory immune response in models of autoimmunity including inflammatory bowel disease and provide a rationale for use of probiotics in HIV-1/AIDS. Disturbance of the microbiota early in HIV-1 infection leads to greater dominance of potential pathogens, reducing levels of bifidobacteria and lactobacillus species and increasing mucosal inflammation. The interaction of chronic or recurrent infections, and immune activation contributes to nutritional deficiencies that have lasting consequences especially in the HIV-1 infected child. While effective anti-retroviral therapy (ART has enhanced survival, wasting is still an independent predictor of survival and a major presenting symptom. Congenital exposure to HIV-1 is a risk factor for growth delay in both infected and non-infected infants. Nutritional intervention after 6 months of age appears to be largely ineffective. A meta analysis of randomized, controlled clinical trials of infant formulae supplemented with Bifidobacterium lactis showed that weight gain was significantly greater in infants who received B. lactis compared to

Plant Immunity against Viruses: Moving from the Lab to the Field

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Nam-Yeon Kim

2018-03-01

Full Text Available Plant viruses cause significant yield losses and continuously threaten crop production, representing a serious threat to global food security. Studies on plant-virus interactions have contributed to increase our knowledge on plant immunity mechanism, providing new strategies for crop improvement. The prophylactic managements consist mainly following international legislations, eradication of infected plants, and application of pesticide to decrease the population of vectors. Hence, putting together the pieces of knowledge related to molecular plant immunity to viruses is critical for the control of virus disease in fields. Over the last several decades, the outstanding outcomes of extensive research have been achieved on comprehension of plant immunity to viruses. Although most dominant R genes have been used as natural resistance genes, recessive resistance genes have been deployed in several crops as another efficient strategy to control viruses. In addition, RNA interference also regulates plant immunity and contribute a very efficient antiviral system at the nucleic acid level. This review aims at describing virus disease on crops and summarizes current resistance mechanisms. Furthermore, we will discuss the current biotechnological approaches to control viral diseases and the future questions that are to be addressed to secure crop production against viruses.

T Cell-Mediated Immunity towards Yellow Fever Virus and Useful Animal Models

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Watson, Alan M.; Klimstra, William B.

2017-01-01

The 17D line of yellow fever virus vaccines is among the most effective vaccines ever created. The humoral and cellular immunity elicited by 17D has been well characterized in humans. Neutralizing antibodies have long been known to provide protection against challenge with a wild-type virus. However, a well characterized T cell immune response that is robust, long-lived and polyfunctional is also elicited by 17D. It remains unclear whether this arm of immunity is protective following challenge with a wild-type virus. Here we introduce the 17D line of yellow fever virus vaccines, describe the current state of knowledge regarding the immunity directed towards the vaccines in humans and conclude with a discussion of animal models that are useful for evaluating T cell-mediated immune protection to yellow fever virus. PMID:28398253

Distinct T and NK cell populations may serve as immune correlates of protection against symptomatic pandemic influenza A(H1N1 virus infection during pregnancy.

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Miloje Savic

Full Text Available Maternal influenza infection during pregnancy is associated with increased risk of morbidity and mortality. However, the link between the anti-influenza immune responses and health-related risks during infection is not well understood. We have analyzed memory T and NK cell mediated immunity (CMI responses in pandemic influenza A(H1N1pdm09 (pdm09 virus infected non-vaccinated pregnant women participating in the Norwegian Influenza Pregnancy Cohort (NorFlu. The cohort includes information on immunization, self-reported health and disease status, and biological samples (plasma and PBMC. Infected cases (N = 75 were defined by having a serum hemagglutination inhibition (HI titer > = 20 to influenza pdm09 virus at the time of delivery, while controls (N = 75 were randomly selected among non-infected pregnant women (HI titer <10. In ELISpot assays cases had higher frequencies of IFNγ+ CD8+ T cells responding to pdm09 virus or conserved CD8 T cell-restricted influenza A virus epitopes, compared to controls. Within this T cell population, frequencies of CD95+ late effector (CD45RA+CCR7- and naive (CD45RA+CCR7+ CD8+ memory T cells correlated inversely with self-reported influenza illness (ILI symptoms. ILI symptoms in infected women were also associated with lower numbers of poly-functional (IFNγ+TNFα+, IL2+IFNγ+, IL2+IFNγ+TNFα+ CD4+ T cells and increased frequencies of IFNγ+CD3-CD7+ NK cells compared to asymptomatic cases, or controls, after stimulation with the pdm09 virus. Taken together, virus specific and functionally distinct T and NK cell populations may serve as cellular immune correlates of clinical outcomes of pandemic influenza disease in pregnant women. Our results may provide information important for future universal influenza vaccine design.

Distinct T and NK cell populations may serve as immune correlates of protection against symptomatic pandemic influenza A(H1N1) virus infection during pregnancy.

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Savic, Miloje; Dembinski, Jennifer L; Laake, Ida; Hungnes, Olav; Cox, Rebecca; Oftung, Fredrik; Trogstad, Lill; Mjaaland, Siri

2017-01-01

Maternal influenza infection during pregnancy is associated with increased risk of morbidity and mortality. However, the link between the anti-influenza immune responses and health-related risks during infection is not well understood. We have analyzed memory T and NK cell mediated immunity (CMI) responses in pandemic influenza A(H1N1)pdm09 (pdm09) virus infected non-vaccinated pregnant women participating in the Norwegian Influenza Pregnancy Cohort (NorFlu). The cohort includes information on immunization, self-reported health and disease status, and biological samples (plasma and PBMC). Infected cases (N = 75) were defined by having a serum hemagglutination inhibition (HI) titer > = 20 to influenza pdm09 virus at the time of delivery, while controls (N = 75) were randomly selected among non-infected pregnant women (HI titer <10). In ELISpot assays cases had higher frequencies of IFNγ+ CD8+ T cells responding to pdm09 virus or conserved CD8 T cell-restricted influenza A virus epitopes, compared to controls. Within this T cell population, frequencies of CD95+ late effector (CD45RA+CCR7-) and naive (CD45RA+CCR7+) CD8+ memory T cells correlated inversely with self-reported influenza illness (ILI) symptoms. ILI symptoms in infected women were also associated with lower numbers of poly-functional (IFNγ+TNFα+, IL2+IFNγ+, IL2+IFNγ+TNFα+) CD4+ T cells and increased frequencies of IFNγ+CD3-CD7+ NK cells compared to asymptomatic cases, or controls, after stimulation with the pdm09 virus. Taken together, virus specific and functionally distinct T and NK cell populations may serve as cellular immune correlates of clinical outcomes of pandemic influenza disease in pregnant women. Our results may provide information important for future universal influenza vaccine design.

Immune responses of ducks infected with duck Tembusu virus

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Ning eLi

2015-05-01

Full Text Available Duck Tembusu virus (DTMUV can cause serious disease in ducks, characterized by reduced egg production. Although the virus has been isolated and detection methods developed, the host immune responses to DTMUV infection are unclear. Therefore, we systematically examined the expression of immune-related genes and the viral distribution in DTMUV-infected ducks, using quantitative real-time PCR. Our results show that DTMUV replicates quickly in many tissues early in infection, with the highest viral titers in the spleen 1 day after infection. Rig-1, Mda5, and Tlr3 are involved in the host immune response to DTMUV, and the expression of proinflammatory cytokines (Il-1β, -2, -6, Cxcl8 and antiviral proteins (Mx, Oas, etc. are also upregulated early in infection. The expression of Il-6 increased most significantly in the tissues tested. The upregulation of Mhc-I was observed in the brain and spleen, but the expression of Mhc-II was upregulated in the brain and downregulated in the spleen. The expression of the interferons was also upregulated to different degrees in the spleen but that of the brain was various. Our study suggests that DTMUV replicates rapidly in various tissues and that the host immune responses are activated early in infection. However, the overexpression of cytokines may damage the host. These results extend our understanding of the immune responses of ducks to DTMUV infection, and provide insight into the pathogenesis of DTMUV attributable to host factors.

Cutting edge: impairment of dendritic cells and adaptive immunity by Ebola and Lassa viruses.

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Mahanty, Siddhartha; Hutchinson, Karen; Agarwal, Sudhanshu; McRae, Michael; Rollin, Pierre E; Pulendran, Bali

2003-03-15

Acute infection of humans with Ebola and Lassa viruses, two principal etiologic agents of hemorrhagic fevers, often results in a paradoxical pattern of immune responses: early infection, characterized by an outpouring of inflammatory mediators such as TNF-alpha, IL-1 beta, and IL-6, vs late stage infections, which are associated with poor immune responses. The mechanisms underlying these diverse outcomes are poorly understood. In particular, the role played by cells of the innate immune system, such as dendritic cells (DC), is not known. In this study, we show that Ebola and Lassa viruses infect human monocyte-derived DC and impair their function. Monocyte-derived DC exposed to either virus fail to secrete proinflammatory cytokines, do not up-regulate costimulatory molecules, and are poor stimulators of T cells. These data represent the first evidence for a mechanism by which Ebola and Lassa viruses target DC to impair adaptive immunity.

Opposing effects of CXCR3 and CCR5 deficiency on CD8+ T cell-mediated inflammation in the central nervous system of virus-infected mice

DEFF Research Database (Denmark)

de Lemos, Carina; Christensen, Jeanette Erbo; Nansen, Anneline

2005-01-01

and therefore protect mice against the otherwise fatal CD8+ T cell-mediated immune attack. Contrary to expectations, the accumulation of mononuclear cells in cerebrospinal fluid was only slightly delayed compared with mice with normal expression of both receptors. Even more surprising, CXCR3/CCR5 double-deficient......T cells play a key role in the control of viral infection in the CNS but may also contribute to immune-mediated cell damage. To study the redundancy of the chemokine receptors CXCR3 and CCR5 in regulating virus-induced CD8+ T cell-mediated inflammation in the brain, CXCR3/CCR5 double-deficient mice...... mice were more susceptible to intracerebral infection than CXCR3-deficient mice. Analysis of effector T cell generation revealed an accelerated antiviral CD8+ T cell response in CXCR3/CCR5 double-deficient mice. Furthermore, while the accumulation of CD8+ T cells in the neural parenchyma...

Immune Memory to Sudan Virus: Comparison between Two Separate Disease Outbreaks

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Ariel Sobarzo

2015-01-01

Full Text Available Recovery from ebolavirus infection in humans is associated with the development of both cell-mediated and humoral immune responses. According to recent studies, individuals that did not survive infection with ebolaviruses appear to have lacked a robust adaptive immune response and the expression of several early innate response markers. However, a comprehensive protective immune profile has yet to be described. Here, we examine cellular memory immune responses among survivors of two separate Ebolavirus outbreaks (EVDs due to Sudan virus (SUDV infection in Uganda—Gulu 2000–2001 and Kibaale 2012. Freshly collected blood samples were stimulated with inactivated SUDV, as well as with recombinant SUDV or Ebola virus (EBOV GP (GP1–649. In addition, ELISA and plaque reduction neutralization assays were performed to determine anti-SUDV IgG titers and neutralization capacity. Cytokine expression was measured in whole blood cultures in response to SUDV and SUDV GP stimulation in both survivor pools, demonstrating recall responses that indicate immune memory. Cytokine responses between groups were similar but had distinct differences. Neutralizing, SUDV-specific IgG activity against irradiated SUDV and SUDV recombinant proteins were detected in both survivor cohorts. Furthermore, humoral and cell-mediated crossreactivity to EBOV and EBOV recombinant GP1–649 was observed in both cohorts. In conclusion, immune responses in both groups of survivors demonstrate persistent recognition of relevant antigens, albeit larger cohorts are required in order to reach greater statistical significance. The differing cytokine responses between Gulu and Kibaale outbreak survivors suggests that each outbreak may not yield identical memory responses and promotes the merits of studying the immune responses among outbreaks of the same virus. Finally, our demonstration of cross-reactive immune recognition suggests that there is potential for developing cross

Replication-deficient mutant Herpes Simplex Virus-1 targets professional antigen presenting cells and induces efficient CD4+ T helper responses.

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Fiorentini, Simona; Marconi, Peggy; Avolio, Manuela; Marini, Elena; Garrafa, Emirena; Caracciolo, Sonia; Rossi, Daniele; Bozac, Alexandra; Becker, Pablo D; Gentili, Francesca; Facchetti, Fabio; Guzman, Carlos A; Manservigi, Roberto; Caruso, Arnaldo

2007-07-01

Both neutralizing antibodies and cytotoxic T-cells are necessary to control a viral infection. However, vigorous T helper responses are essential for their elicitation and maintenance. Here we show that a recombinant replication-deficient Herpes Simplex Virus (HSV)-1 vector encoding the Human Immunodeficiency Virus (HIV)-1 matrix protein p17 (T0-p17) was capable of infecting professional antigen presenting cells (APCs) in vitro and in vivo. The injection of T0-p17 in the mouse dermis generated a strong p17-specific CD4+ T helper response preceding both p17-specific humoral and effector T cell responses. Moreover, we show that T0-p17 infection did not interfere with the endogenous processing of the transgene encoded antigen, since infected APCs were able to evoke a strong recall response in vitro. Our results demonstrate that replication-deficient HSV vectors can be appealing candidates for the development of vaccines able to trigger T helper responses.

Hepatitis B Virus Vaccine immune response in Egyptian children 15 ...

African Journals Online (AJOL)

Egypt J Pediatr Allergy Immunol 2015;13(2):45-48. 45. Hepatitis B Virus Vaccine immune response in Egyptian children 15-17 years after primary immunization; should we provide a booster dose? INTRODUCTION. Hepatitis B virus (HBV) infection is a global public health problem. With approximately 350 million hepatitis B ...

Immune cells: more than simple carriers for systemic delivery of oncolytic viruses

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Eisenstein S

2014-11-01

Full Text Available Samuel Eisenstein,1 Shu-Hsia Chen,2 Ping-Ying Pan21Department of Surgery, 2Department of Oncological Sciences and Tisch Cancer Institute, The Icahn School of Medicine at Mount Sinai, New York, NY, USAAbstract: Oncolytic virotherapy on its own has numerous drawbacks, including an inability of the virus to actively target tumor cells and systemic toxicities at the high doses necessary to effectively treat tumors. Addition of immune cell-based carriers of oncolytic viruses holds promise as a technique in which oncolytic virus can be delivered directly to tumors in smaller and less toxic doses. Interestingly, the cell carriers themselves have also demonstrated antitumor effects, which can be augmented further by tailoring the appropriate oncolytic virus to the appropriate cell type. This review discusses the multiple factors that go into devising an effective, cell-based delivery system for oncolytic viruses.Keywords: oncolytic virus, cell carrier, immune cells, cancer therapy, myeloid-derived suppressor cells

Genome-wide RNAi screen reveals a new role of a WNT/CTNNB1 signaling pathway as negative regulator of virus-induced innate immune responses.

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Baril, Martin; Es-Saad, Salwa; Chatel-Chaix, Laurent; Fink, Karin; Pham, Tram; Raymond, Valérie-Ann; Audette, Karine; Guenier, Anne-Sophie; Duchaine, Jean; Servant, Marc; Bilodeau, Marc; Cohen, Eric; Grandvaux, Nathalie; Lamarre, Daniel

2013-01-01

To identify new regulators of antiviral innate immunity, we completed the first genome-wide gene silencing screen assessing the transcriptional response at the interferon-β (IFNB1) promoter following Sendai virus (SeV) infection. We now report a novel link between WNT signaling pathway and the modulation of retinoic acid-inducible gene I (RIG-I)-like receptor (RLR)-dependent innate immune responses. Here we show that secretion of WNT2B and WNT9B and stabilization of β-catenin (CTNNB1) upon virus infection negatively regulate expression of representative inducible genes IFNB1, IFIT1 and TNF in a CTNNB1-dependent effector mechanism. The antiviral response is drastically reduced by glycogen synthase kinase 3 (GSK3) inhibitors but restored in CTNNB1 knockdown cells. The findings confirm a novel regulation of antiviral innate immunity by a canonical-like WNT/CTNNB1 signaling pathway. The study identifies novel avenues for broad-spectrum antiviral targets and preventing immune-mediated diseases upon viral infection.

Genome-wide RNAi screen reveals a new role of a WNT/CTNNB1 signaling pathway as negative regulator of virus-induced innate immune responses.

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Martin Baril

Full Text Available To identify new regulators of antiviral innate immunity, we completed the first genome-wide gene silencing screen assessing the transcriptional response at the interferon-β (IFNB1 promoter following Sendai virus (SeV infection. We now report a novel link between WNT signaling pathway and the modulation of retinoic acid-inducible gene I (RIG-I-like receptor (RLR-dependent innate immune responses. Here we show that secretion of WNT2B and WNT9B and stabilization of β-catenin (CTNNB1 upon virus infection negatively regulate expression of representative inducible genes IFNB1, IFIT1 and TNF in a CTNNB1-dependent effector mechanism. The antiviral response is drastically reduced by glycogen synthase kinase 3 (GSK3 inhibitors but restored in CTNNB1 knockdown cells. The findings confirm a novel regulation of antiviral innate immunity by a canonical-like WNT/CTNNB1 signaling pathway. The study identifies novel avenues for broad-spectrum antiviral targets and preventing immune-mediated diseases upon viral infection.

PD-L1 Deficiency within Islets Reduces Allograft Survival in Mice.

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Dongxia Ma

Full Text Available Islet transplantation may potentially cure type 1 diabetes mellitus (T1DM. However, immune rejection, especially that induced by the alloreactive T-cell response, remains a restraining factor for the long-term survival of grafted islets. Programmed death ligand-1 (PD-L1 is a negative costimulatory molecule. PD-L1 deficiency within the donor heart accelerates allograft rejection. Here, we investigate whether PD-L1 deficiency in donor islets reduces allograft survival time.Glucose Stimulation Assays were performed to evaluate whether PD-L1 deficiency has detrimental effects on islet function. Islets isolated from PDL1-deficient mice or wild- type (WT mice (C57BL/6j were implanted beneath the renal capsule of streptozotocin (STZ-induced diabetic BALB/c mice. Blood glucose levels and graft survival time after transplantation were monitored. Moreover, we analyzed the residual islets, infiltrating immune cells and alloreactive cells from the recipients.PD-L1 deficiency within islets does not affect islet function. However, islet PD-L1 deficiency increased allograft rejection and was associated with enhanced inflammatory cell infiltration and recipient T-cell alloreactivity.This is the first report to demonstrate that PD-L1 deficiency accelerated islet allograft rejection and regulated recipient alloimmune responses.

Protective immunity and safety of a genetically modified influenza virus vaccine.

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Rafael Polidoro Alves Barbosa

Full Text Available Recombinant influenza viruses are promising viral platforms to be used as antigen delivery vectors. To this aim, one of the most promising approaches consists of generating recombinant viruses harboring partially truncated neuraminidase (NA segments. To date, all studies have pointed to safety and usefulness of this viral platform. However, some aspects of the inflammatory and immune responses triggered by those recombinant viruses and their safety to immunocompromised hosts remained to be elucidated. In the present study, we generated a recombinant influenza virus harboring a truncated NA segment (vNA-Δ and evaluated the innate and inflammatory responses and the safety of this recombinant virus in wild type or knock-out (KO mice with impaired innate (Myd88 -/- or acquired (RAG -/- immune responses. Infection using truncated neuraminidase influenza virus was harmless regarding lung and systemic inflammatory response in wild type mice and was highly attenuated in KO mice. We also demonstrated that vNA-Δ infection does not induce unbalanced cytokine production that strongly contributes to lung damage in infected mice. In addition, the recombinant influenza virus was able to trigger both local and systemic virus-specific humoral and CD8+ T cellular immune responses which protected immunized mice against the challenge with a lethal dose of homologous A/PR8/34 influenza virus. Taken together, our findings suggest and reinforce the safety of using NA deleted influenza viruses as antigen delivery vectors against human or veterinary pathogens.

Fluorescent dye labeled influenza virus mainly infects innate immune cells and activated lymphocytes and can be used in cell-mediated immune response assay

OpenAIRE

Xie, Dongxu

2009-01-01

Early results have recognized that influenza virus infects the innate and adaptive immune cells. The data presented in this paper demonstrated that influenza virus labeled with fluorescent dye not only retained the ability to infect and replicate in host cells, but also stimulated a similar human immune response as did unlabeled virus. Influenza virus largely infected the innate and activated adaptive immune cells. Influenza B type virus was different from that of A type virus. B type virus w...

Expression of innate immune genes, proteins and microRNAs in lung tissue of pigs infected experimentally with influenza virus (H1N2)

DEFF Research Database (Denmark)

Skovgaard, Kerstin; Cirera, Susanna; Vasby, Ditte

2013-01-01

This study aimed at providing a better understanding of the involvement of innate immune factors, including miRNA, in the local host response to influenza virus infection. Twenty pigs were challenged by influenza A virus subtype H1N2. Expression of microRNA (miRNA), mRNA and proteins were...... results suggest that, in addition to a wide range of innate immune factors, miRNAs may also be involved in controlling acute influenza infection in pigs....

Incidence of adverse drug reactions in human immune deficiency virus-positive patients using highly active antiretroviral therapy

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B Akshaya Srikanth

2012-01-01

Full Text Available To estimate the incidence of adverse drug reactions (ADRs in Human immune deficiency virus (HIV patients on highly active antiretroviral therapy (HAART. To identify the risk factors associated with ADRs in HIV patients. To analyze reported ADRs based on various parameters like causality, severity, predictability, and preventability. Retrospective case-control study. An 18-month retrospective case-control study of 208 patients newly registered in ART center, RIMS hospital, Kadapa, were intensively monitored for ADRs to HAART. Predictability was calculated based on the history of previous exposure to drug. Multivariate logistic regressions were used to identify the risk factors for ADRs. Data were analyzed using the chi-square test for estimating the correlation between ADRs and different variables. All statistical calculations were performed using EpiInfo version 3.5.3. Monitoring of 208 retrospective patients by active Pharmacovigilance identified 105 ADRs that were identified in 71 patients. Skin rash and anemia were the most commonly observed ADRs. The organ system commonly affected by ADR was skin and appendages (31.57%. The ADRs that were moderate were 90.14% of cases. The incidence of ADRs (53.52% was higher with Zidovudine + Lamivudine + Nevirapine combination. CD4 cell count less than <250 cells/μl were 80.28%, male gender were observed to be the risk factors for ADRs. Our study finding showed that there is a need of active pharmaceutical care with intensive monitoring for ADRs in Indian HIV-positive patients who are illiterate, of male and female gender, with CD4 count ≤250 cells/mm 3 with comorbid conditions.

Risky sexual behaviour and human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) among healthcare workers.

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Khamisa, Natasha; Mokgobi, Maboe

2018-01-01

South Africa is known to have one of the highest prevalence rates of human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) globally, with one in seven healthcare workers being HIV-positive. An HIV-positive healthcare workforce is less equipped to respond to the increasing spread of the epidemic. Assessment of the factors contributing to high HIV prevalence rates among healthcare workers is important in planning the development of human resources. This review sought to identify and understand predominant risky sexual behaviours among healthcare workers in HIV and AIDS-affected countries. This study reviewed articles focusing on sexual behaviour among healthcare workers. Major health science databases (e.g. ProQuest, Cochrane, PubMed and CINAHL) were searched for combinations of keywords including 'healthcare workers', 'risky sexual behaviour' and 'HIV and AIDS'. Articles from a range of countries met inclusion and exclusion criteria. Findings of the study revealed three main contributing factors: unprotected sex, multiple sex partners and sexual violence. Sexual violence emerged as the dominant risk factor in the majority of the studies. Most research was conducted in developed countries where the HIV infection rate is much lower than it is in developing countries. More research needs to be conducted in developing countries and appropriate strategies should be implemented to reduce sexual violence among healthcare workers. Appropriate procedures on reporting sexual violence coupled with education on HIV and AIDS as well as influencing attitudes and belief systems could assist in reducing the spread of HIV and AIDS within the healthcare workforce while minimising the effect on patient care.

Virus-Heat Shock Protein Interaction and a Novel Axis for Innate Antiviral Immunity

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Michael Oglesbee

2012-09-01

Full Text Available Virus infections induce heat shock proteins that in turn enhance virus gene expression, a phenomenon that is particularly well characterized for the major inducible 70 kDa heat shock protein (hsp70. However, hsp70 is also readily induced by fever, a phylogenetically conserved response to microbial infections, and when released from cells, hsp70 can stimulate innate immune responses through toll like receptors 2 and 4 (TLR2 and 4. This review examines how the virus-hsp70 relationship can lead to host protective innate antiviral immunity, and the importance of hsp70 dependent stimulation of virus gene expression in this host response. Beginning with the well-characterized measles virus-hsp70 relationship and the mouse model of neuronal infection in brain, we examine data indicating that the innate immune response is not driven by intracellular sensors of pathogen associated molecular patterns, but rather by extracellular ligands signaling through TLR2 and 4. Specifically, we address the relationship between virus gene expression, extracellular release of hsp70 (as a damage associated molecular pattern, and hsp70-mediated induction of antigen presentation and type 1 interferons in uninfected macrophages as a novel axis of antiviral immunity. New data are discussed that examines the more broad relevance of this protective mechanism using vesicular stomatitis virus, and a review of the literature is presented that supports the probable relevance to both RNA and DNA viruses and for infections both within and outside of the central nervous system.

DNA immunization with a herpes simplex virus 2 bacterial artificial chromosome

International Nuclear Information System (INIS)

Meseda, Clement A.; Schmeisser, Falko; Pedersen, Robin; Woerner, Amy; Weir, Jerry P.

2004-01-01

Construction of a herpes simplex virus 2 (HSV-2) bacterial artificial chromosome (BAC) is described. BAC vector sequences were inserted into the thymidine kinase gene of HSV-2 by homologous recombination. DNA from cells infected with the resulting recombinant virus was transformed into E. coli, and colonies containing the HSV-2 BAC (HSV2-BAC) were isolated and analyzed for the expected genotype. HSV2-BAC DNA was infectious when transfected back into mammalian cells and the resulting virus was thymidine kinase negative. When used to immunize mice, the HSV2-BAC DNA elicited a strong HSV-2 specific antibody response that was equal to or greater than live virus immunization. Further, HSV2-BAC immunization was protective when animals were challenged with a lethal dose of virus. The utility of the HSV2-BAC for construction of recombinant virus genomes was demonstrated by elimination of the HSV-2 glycoprotein D (gD) gene. A recombinant HSV-2 BAC with the gD gene deleted was isolated and shown to be incapable of producing infectious virus following transfection unless an HSV gD gene was expressed in a complementing cell line. Immunization of mice with the HSV2 gD-BAC also elicited an HSV-2 specific antibody response and was protective. The results demonstrate the feasibility of DNA immunization with HSV-2 bacterial artificial chromosomes for replicating and nonreplicating candidate HSV-2 vaccines, as well as the utility of BAC technology for construction and maintenance of novel HSV-2 vaccines. The results further suggest that such technology will be a powerful tool for dissecting the immune response to HSV-2

Heterosubtypic immunity to influenza A virus infections in mallards may explain existence of multiple virus subtypes.

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Neus Latorre-Margalef

Full Text Available Wild birds, particularly duck species, are the main reservoir of influenza A virus (IAV in nature. However, knowledge of IAV infection dynamics in the wild bird reservoir, and the development of immune responses, are essentially absent. Importantly, a detailed understanding of how subtype diversity is generated and maintained is lacking. To address this, 18,679 samples from 7728 Mallard ducks captured between 2002 and 2009 at a single stopover site in Sweden were screened for IAV infections, and the resulting 1081 virus isolates were analyzed for patterns of immunity. We found support for development of homosubtypic hemagglutinin (HA immunity during the peak of IAV infections in the fall. Moreover, re-infections with the same HA subtype and related prevalent HA subtypes were uncommon, suggesting the development of natural homosubtypic and heterosubtypic immunity (p-value = 0.02. Heterosubtypic immunity followed phylogenetic relatedness of HA subtypes, both at the level of HA clades (p-value = 0.04 and the level of HA groups (p-value = 0.05. In contrast, infection patterns did not support specific immunity for neuraminidase (NA subtypes. For the H1 and H3 Clades, heterosubtypic immunity showed a clear temporal pattern and we estimated within-clade immunity to last at least 30 days. The strength and duration of heterosubtypic immunity has important implications for transmission dynamics of IAV in the natural reservoir, where immune escape and disruptive selection may increase HA antigenic variation and explain IAV subtype diversity.

A Hepatocellular Carcinoma Case in a Patient Who had Immunity to Hepatitis B Virus Earlier.

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Ates, Ihsan; Kaplan, Mustafa; Demirci, Selim; Altiparmak, Emin

2016-01-01

Hepatocellular carcinoma (HCC) is the most common malignant tumor of the liver. Hepatitis B virus infection is one of the most important etilogical factors of HCC. In this case report, a patient with HCC previously infected and having ongoing immunity against hepatitis B virus will be discussed. Ates I, Kaplan M, Demirci S, Altiparmak E. A Hepatocellular Carcinoma Case in a Patient Who had Immunity to Hepatitis B Virus Earlier. Euroasian J Hepato-Gastroenterol 2016;6(1):82-83.

Evasion of T cell immunity by Epstein-Barr virus

NARCIS (Netherlands)

Horst, D.

2011-01-01

Immune evasion strategies are thought to contribute essentially to the life cycle of persistent viruses by delaying the elimination of the infected cell long enough to enable the virus to replicate. Exemplary in this context are the herpesviruses, large DNA viruses that are carried as a persistent

The Role of Nuclear Medicine in the Staging and Management of Human Immune Deficiency Virus Infection and Associated Diseases.

Science.gov (United States)

Ankrah, Alfred O; Glaudemans, Andor W J M; Klein, Hans C; Dierckx, Rudi A J O; Sathekge, Mike

2017-06-01

Human immune deficiency virus (HIV) is a leading cause of death. It attacks the immune system, thereby rendering the infected host susceptible to many HIV-associated infections, malignancies and neurocognitive disorders. The altered immune system affects the way the human host responds to disease, resulting in atypical presentation of these disorders. This presents a diagnostic challenge and the clinician must use all diagnostic avenues available to diagnose and manage these conditions. The advent of highly active antiretroviral therapy (HAART) has markedly reduced the mortality associated with HIV infection but has also brought in its wake problems associated with adverse effects or drug interaction and may even modulate some of the HIV-associated disorders to the detriment of the infected human host. Nuclear medicine techniques allow non-invasive visualisation of tissues in the body. By using this principle, pathophysiology in the body can be targeted and the treatment of diseases can be monitored. Being a functional imaging modality, it is able to detect diseases at the molecular level, and thus it has increased our understanding of the immunological changes in the infected host at different stages of the HIV infection. It also detects pathological changes much earlier than conventional imaging based on anatomical changes. This is important in the immunocompromised host as in some of the associated disorders a delay in diagnosis may have dire consequences. Nuclear medicine has played a huge role in the management of many HIV-associated disorders in the past and continues to help in the diagnosis, prognosis, staging, monitoring and assessing the response to treatment of many HIV-associated disorders. As our understanding of the molecular basis of disease increases nuclear medicine is poised to play an even greater role. In this review we highlight the functional basis of the clinicopathological correlation of HIV from a metabolic view and discuss how the use of

The role of nuclear medicine in the staging and management of human immune deficiency virus infection and associated diseases

International Nuclear Information System (INIS)

Ankrah, Alfred O.; Sathekge, Mike; Glaudemans, Andor W. J. M.; Klein, Hans; Dierckx, Rudi A. J. O.

2017-01-01

Human immune deficiency virus (HIV) is a leading cause of death. It attacks the immune system, thereby rendering the infected host susceptible to many HIV-associated infections, malignancies and neurocognitive disorders. The altered immune system affects the way the human host responds to disease, resulting in atypical presentation of these disorders. This presents a diagnostic challenge and the clinician must use all diagnostic avenues available to diagnose and manage these conditions. The advent of highly active antiretroviral therapy (HAART) has markedly reduced the mortality associated with HIV infection but has also brought in its wake problems associated with adverse effects or drug interaction and may even modulate some of the HIV-associated disorders to the detriment of the infected human host. Nuclear medicine techniques allow non-invasive visualisation of tissues in the body. By using this principle, pathophysiology in the body can be targeted and the treatment of diseases can be monitored. Being a functional imaging modality, it is able to detect diseases at the molecular level, and thus it has increased our understanding of the immunological changes in the infected host at different stages of the HIV infection. It also detects pathological changes much earlier than conventional imaging based on anatomical changes. This is important in the immunocompromised host as in some of the associated disorders a delay in diagnosis may have dire consequences. Nuclear medicine has played a huge role in the management of many HIV-associated disorders in the past and continues to help in the diagnosis, prognosis, staging, monitoring and assessing the response to treatment of many HIV-associated disorders. As our understanding of the molecular basis of disease increases nuclear medicine is poised to play an even greater role. In this review we highlight the functional basis of the clinicopathological correlation of HIV from a metabolic view and discuss how the use of

The role of nuclear medicine in the staging and management of human immune deficiency virus infection and associated diseases

Energy Technology Data Exchange (ETDEWEB)

Ankrah, Alfred O.; Sathekge, Mike [Dept. of Nuclear Medicine, University of Pretoria and Steve Biko Academic Hospital, Pretoria (South Africa); Glaudemans, Andor W. J. M.; Klein, Hans; Dierckx, Rudi A. J. O. [University of Groningen, University Medical Centre Groningen, Groningen (Netherlands)

2017-06-15

Human immune deficiency virus (HIV) is a leading cause of death. It attacks the immune system, thereby rendering the infected host susceptible to many HIV-associated infections, malignancies and neurocognitive disorders. The altered immune system affects the way the human host responds to disease, resulting in atypical presentation of these disorders. This presents a diagnostic challenge and the clinician must use all diagnostic avenues available to diagnose and manage these conditions. The advent of highly active antiretroviral therapy (HAART) has markedly reduced the mortality associated with HIV infection but has also brought in its wake problems associated with adverse effects or drug interaction and may even modulate some of the HIV-associated disorders to the detriment of the infected human host. Nuclear medicine techniques allow non-invasive visualisation of tissues in the body. By using this principle, pathophysiology in the body can be targeted and the treatment of diseases can be monitored. Being a functional imaging modality, it is able to detect diseases at the molecular level, and thus it has increased our understanding of the immunological changes in the infected host at different stages of the HIV infection. It also detects pathological changes much earlier than conventional imaging based on anatomical changes. This is important in the immunocompromised host as in some of the associated disorders a delay in diagnosis may have dire consequences. Nuclear medicine has played a huge role in the management of many HIV-associated disorders in the past and continues to help in the diagnosis, prognosis, staging, monitoring and assessing the response to treatment of many HIV-associated disorders. As our understanding of the molecular basis of disease increases nuclear medicine is poised to play an even greater role. In this review we highlight the functional basis of the clinicopathological correlation of HIV from a metabolic view and discuss how the use of

Modelling the innate immune response against avian influenza virus in chicken

NARCIS (Netherlands)

Hagenaars, T.J.; Fischer, E.A.J.; Jansen, C.A.; Rebel, J.M.J.; Spekreijse, D.; Vervelde, L.; Backer, J.A.; Jong, de M.C.M.; Koets, A.P.

2016-01-01

At present there is limited understanding of the host immune response to (low pathogenic) avian influenza virus infections in poultry. Here we develop a mathematical model for the innate immune response to avian influenza virus in chicken lung, describing the dynamics of viral load,

Induction of ebolavirus cross-species immunity using retrovirus-like particles bearing the Ebola virus glycoprotein lacking the mucin-like domain.

Science.gov (United States)

Ou, Wu; Delisle, Josie; Jacques, Jerome; Shih, Joanna; Price, Graeme; Kuhn, Jens H; Wang, Vivian; Verthelyi, Daniela; Kaplan, Gerardo; Wilson, Carolyn A

2012-01-25

The genus Ebolavirus includes five distinct viruses. Four of these viruses cause hemorrhagic fever in humans. Currently there are no licensed vaccines for any of them; however, several vaccines are under development. Ebola virus envelope glycoprotein (GP1,2) is highly immunogenic, but antibodies frequently arise against its least conserved mucin-like domain (MLD). We hypothesized that immunization with MLD-deleted GP1,2 (GPΔMLD) would induce cross-species immunity by making more conserved regions accessible to the immune system. To test this hypothesis, mice were immunized with retrovirus-like particles (retroVLPs) bearing Ebola virus GPΔMLD, DNA plasmids (plasmo-retroVLP) that can produce such retroVLPs in vivo, or plasmo-retroVLP followed by retroVLPs. Cross-species neutralizing antibody and GP1,2-specific cellular immune responses were successfully induced. Our findings suggest that GPΔMLD presented through retroVLPs may provide a strategy for development of a vaccine against multiple ebolaviruses. Similar vaccination strategies may be adopted for other viruses whose envelope proteins contain highly variable regions that may mask more conserved domains from the immune system.

Heterologous prime-boost immunization of Newcastle disease virus vectored vaccines protected broiler chickens against highly pathogenic avian influenza and Newcastle disease viruses.

Science.gov (United States)

Kim, Shin-Hee; Samal, Siba K

2017-07-24

Avian Influenza virus (AIV) is an important pathogen for both human and animal health. There is a great need to develop a safe and effective vaccine for AI infections in the field. Live-attenuated Newcastle disease virus (NDV) vectored AI vaccines have shown to be effective, but preexisting antibodies to the vaccine vector can affect the protective efficacy of the vaccine in the field. To improve the efficacy of AI vaccine, we generated a novel vectored vaccine by using a chimeric NDV vector that is serologically distant from NDV. In this study, the protective efficacy of our vaccines was evaluated by using H5N1 highly pathogenic avian influenza virus (HPAIV) strain A/Vietnam/1203/2004, a prototype strain for vaccine development. The vaccine viruses were three chimeric NDVs expressing the hemagglutinin (HA) protein in combination with the neuraminidase (NA) protein, matrix 1 protein, or nonstructural 1 protein. Comparison of their protective efficacy between a single and prime-boost immunizations indicated that prime immunization of 1-day-old SPF chicks with our vaccine viruses followed by boosting with the conventional NDV vector strain LaSota expressing the HA protein provided complete protection of chickens against mortality, clinical signs and virus shedding. Further verification of our heterologous prime-boost immunization using commercial broiler chickens suggested that a sequential immunization of chickens with chimeric NDV vector expressing the HA and NA proteins following the boost with NDV vector expressing the HA protein can be a promising strategy for the field vaccination against HPAIVs and against highly virulent NDVs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Population immunity to measles virus and the effect of HIV-1 infection after a mass measles vaccination campaign in Lusaka, Zambia: a cross-sectional survey.

Science.gov (United States)

Lowther, Sara A; Curriero, Frank C; Kalish, Brian T; Shields, Timothy M; Monze, Mwaka; Moss, William J

2009-03-21

Measles control efforts are hindered by challenges in sustaining high vaccination coverage, waning immunity in HIV-1-infected children, and clustering of susceptible individuals. Our aim was to assess population immunity to measles virus after a mass vaccination campaign in a region with high HIV prevalence. 3 years after a measles supplemental immunisation activity (SIA), we undertook a cross-sectional survey in Lusaka, Zambia. Households were randomly selected from a satellite image. Children aged 9 months to 5 years from selected households were eligible for enrolment. A questionnaire was administered to the children's caregivers to obtain information about measles vaccination history and history of measles. Oral fluid samples were obtained from children and tested for antibodies to measles virus and HIV-1 by EIA. 1015 children from 668 residences provided adequate specimens. 853 (84%) children had a history of measles vaccination according to either caregiver report or immunisation card. 679 children (67%) had antibodies to measles virus, and 64 (6%) children had antibodies to HIV-1. Children with antibodies to HIV-1 were as likely to have no history of measles vaccination as those without antibodies to HIV-1 (odds ratio [OR] 1.17, 95% CI 0.57-2.41). Children without measles antibodies were more likely to have never received measles vaccine than those with antibodies (adjusted OR 2.50, 1.69-3.71). In vaccinated children, 33 (61%) of 54 children with antibodies to HIV-1 also had antibodies to measles virus, compared with 568 (71%) of 796 children without antibodies to HIV-1 (p=0.1). 3 years after an SIA, population immunity to measles was insufficient to interrupt measles virus transmission. The use of oral fluid and satellite images for sampling are potential methods to assess population immunity and the timing of SIAs.

Modelling the Innate Immune Response against Avian Influenza Virus in Chicken

NARCIS (Netherlands)

Hagenaars, T J; Fischer, E A J; Jansen, C A; Rebel, J M J; Spekreijse, D; Vervelde, L; Backer, J A; de Jong, M.C.M.; Koets, A P

2016-01-01

At present there is limited understanding of the host immune response to (low pathogenic) avian influenza virus infections in poultry. Here we develop a mathematical model for the innate immune response to avian influenza virus in chicken lung, describing the dynamics of viral load, interferon-α, -β

Antiviral immunity following smallpox virus infection: a case-control study.

Science.gov (United States)

Hammarlund, Erika; Lewis, Matthew W; Hanifin, Jon M; Mori, Motomi; Koudelka, Caroline W; Slifka, Mark K

2010-12-01

Outbreaks of smallpox (i.e., caused by variola virus) resulted in up to 30% mortality, but those who survived smallpox infection were regarded as immune for life. Early studies described the levels of neutralizing antibodies induced after infection, but smallpox was eradicated before contemporary methods for quantifying T-cell memory were developed. To better understand the levels and duration of immunity after smallpox infection, we performed a case-control study comparing antiviral CD4(+) and CD8(+) T-cell responses and neutralizing antibody levels of 24 smallpox survivors with the antiviral immunity observed in 60 smallpox-vaccinated (i.e., vaccinia virus-immune) control subjects. We found that the duration of immunity following smallpox infection was remarkably similar to that observed after smallpox vaccination, with antiviral T-cell responses that declined slowly over time and antiviral antibody responses that remained stable for decades after recovery from infection. These results indicate that severe, potentially life-threatening disease is not required for the development of sustainable long-term immunity. This study shows that the levels of immunity induced following smallpox vaccination are comparable in magnitude to that achieved through natural variola virus infection, and this may explain the notable success of vaccination in eradicating smallpox, one of the world's most lethal diseases.

Antiviral Immunity following Smallpox Virus Infection: a Case-Control Study▿

Science.gov (United States)

Hammarlund, Erika; Lewis, Matthew W.; Hanifin, Jon M.; Mori, Motomi; Koudelka, Caroline W.; Slifka, Mark K.

2010-01-01

Outbreaks of smallpox (i.e., caused by variola virus) resulted in up to 30% mortality, but those who survived smallpox infection were regarded as immune for life. Early studies described the levels of neutralizing antibodies induced after infection, but smallpox was eradicated before contemporary methods for quantifying T-cell memory were developed. To better understand the levels and duration of immunity after smallpox infection, we performed a case-control study comparing antiviral CD4+ and CD8+ T-cell responses and neutralizing antibody levels of 24 smallpox survivors with the antiviral immunity observed in 60 smallpox-vaccinated (i.e., vaccinia virus-immune) control subjects. We found that the duration of immunity following smallpox infection was remarkably similar to that observed after smallpox vaccination, with antiviral T-cell responses that declined slowly over time and antiviral antibody responses that remained stable for decades after recovery from infection. These results indicate that severe, potentially life-threatening disease is not required for the development of sustainable long-term immunity. This study shows that the levels of immunity induced following smallpox vaccination are comparable in magnitude to that achieved through natural variola virus infection, and this may explain the notable success of vaccination in eradicating smallpox, one of the world's most lethal diseases. PMID:20926574

HIV-specific humoral and cellular immunity in rabbits vaccinated with recombinant human immunodeficiency virus-like gag-env particles

International Nuclear Information System (INIS)

Haffar, O.K.; Smithgall, M.D.; Moran, P.A.; Travis, B.M.; Zarling, J.M.; Hu, S.L.

1991-01-01

Recombinant human immunodeficiency virus type-1 (HIV-1)-like gag-env particles produced in mammalian cells were inoculated into two New Zealand white rabbits. In parallel, two control rabbits were inoculated with the homologous HIV-1 virions inactivated by ultraviolet light (uv) and psoralen treatments. The humoral and cellular immune responses to HIV-1 were evaluated for both groups of animals. Recombinant particles elicited humoral immunity that was specific for all the viral structural proteins. The antibodies recognized both denatured and nondenatured proteins. Moreover, the sera neutralized the in vitro infectivity of the homologous virus in CEM cells. Importantly, the recombinant particles also generated a T helper response by priming with the HIV proteins. Similar results were observed with inactivated virus immunization. Therefore, the authors results suggest that the recombinant HIV-like particles elicit functional humoral immunity as well as cellular immunity and represent a novel vaccine candidate for AIDS

Immune Deficiency Disease' of Undetermined Aetiology in Infancy

African Journals Online (AJOL)

1974-04-06

Apr 6, 1974 ... J., 48, 687 (1974). Immune deficiency diseases in infancy are best known as ... tion at the age of 10 months confirmed the mental retarda- tion, and on further ... Examination of other organ systems was non-contributory. Triple .... linked recessive transmitted disease, and has not been re- ported in females.

Feasibility of Measuring Immune Resp, Activation in Foreskin/Mucosa in HIV-, Uncircumcised High-HIV-risk MSM, Lima Peru

Science.gov (United States)

2015-12-10

HIV Infections; Acquired Immunodeficiency Syndrome; Lentivirus Infections; Retroviridae Infections; RNA Virus Infections; Virus Diseases; Sexually Transmitted Diseases, Viral; Sexually Transmitted Diseases; Immunologic Deficiency Syndromes; Immune System Diseases; Slow Virus Diseases

Mongrelised genetics of H1N1 virus: A bird′s eyeview

Directory of Open Access Journals (Sweden)

Nagarathna C

2010-01-01

Full Text Available H1N1 influenza, also known as "novel H1N1 virus" has led to a "global outcry." This virus is more virulent when compared with other seasonal flu viruses. Virulence may change as the adaptive mutation gene increases within the virus. A study at the US Centre for Disease Control and Prevention published in May 2009 found that children had no preexisting immunity to the new strain as they showed no cross-reactive antibody reaction when compared with adults aged 18-64 years, who showed a cross-reactive antibody reaction of 6-9% and older adults with 33% immunity. This review article depicts H1N1 virus, its virulence with genetic evolution potential and preventive protocol for the dental professionals. This would allow us to comprehend the changes in the disease process and contribute in its prevention as "prevention is better than cure."

Immune Evasion Strategies during Chronic Hepatitis B and C Virus Infection

Science.gov (United States)

Ortega-Prieto, Ana Maria; Dorner, Marcus

2017-01-01

Both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are a major global healthcare problem with more than 240 million and 70 million infected, respectively. Both viruses persist within the liver and result in progressive liver disease, resulting in liver fibrosis, cirrhosis and hepatocellular carcinoma. Strikingly, this pathogenesis is largely driven by immune responses, unable to clear an established infection, rather than by the viral pathogens themselves. Even though disease progression is very similar in both infections, HBV and HCV have evolved distinct mechanisms, by which they ensure persistence within the host. Whereas HCV utilizes a cloak-and-dagger approach, disguising itself as a lipid-like particle and immediately crippling essential pattern-recognition pathways, HBV has long been considered a “stealth” virus, due to the complete absence of innate immune responses during infection. Recent developments and access to improved model systems, however, revealed that even though it is among the smallest human-tropic viruses, HBV may, in addition to evading host responses, employ subtle immune evasion mechanisms directed at ensuring viral persistence in the absence of host responses. In this review, we compare the different strategies of both viruses to ensure viral persistence by actively interfering with viral recognition and innate immune responses. PMID:28862649

Immunization with influenza virus hemagglutinin globular region containing the receptor-binding pocket.

Science.gov (United States)

Jeon, Sung Ho; Arnon, Ruth

2002-01-01

The globular region of hemagglutinin (residues 91-261) membrane glycoprotein of influenza virus that encompasses the binding zone to the oligosaccharide receptor of target cells has been cloned by reverse transcriptase-polymerase chain reaction (RT-PCR). This protein segment (denoted HA91-261 peptide) induced significant immune response in mice. The serum antibodies and lung homogenates from the immunized mice cross-reacted with native virus particles. The cellular immunity was manifested by proliferative splenocyte responses and cytokine release indicating T helper type 1 activity. The plasmid DNA containing this segment (denoted pHA91-261) provoked, in addition, a significant cytotoxic T lymphocyte (CTL) response, whereas the HA91-261 protein fragment led to no such response. Both the DNA and the protein fragment of HA91-261 induced significant protection against viral challenge, although the immune response they induce might be along different pathways. Interestingly, the combined DNA priming-protein boosting immunization regimen did not induce protection against viral challenges even though it led to significant humoral immune responses similar to that induced by the peptide vaccine.

A single immunization with a recombinant canine adenovirus expressing the rabies virus G protein confers protective immunity against rabies in mice

International Nuclear Information System (INIS)

Li Jianwei; Faber, Milosz; Papaneri, Amy; Faber, Marie-Luise; McGettigan, James P.; Schnell, Matthias J.; Dietzschold, Bernhard

2006-01-01

Rabies vaccines based on live attenuated rabies viruses or recombinant pox viruses expressing the rabies virus (RV) glycoprotein (G) hold the greatest promise of safety and efficacy, particularly for oral immunization of wildlife. However, while these vaccines induce protective immunity in foxes, they are less effective in other animals, and safety concerns have been raised for some of these vaccines. Because canine adenovirus 2 (CAV2) is licensed for use as a live vaccine for dogs and has an excellent efficacy and safety record, we used this virus as an expression vector for the RVG. The recombinant CAV2-RV G produces virus titers similar to those produced by wild-type CAV2, indicating that the RVG gene does not affect virus replication. Comparison of RVG expressed by CAV2-RV G with that of vaccinia-RV G recombinant virus (V-RG) revealed similar amounts of RV G on the cell surface. A single intramuscular or intranasal immunization of mice with CAV2-RVG induced protective immunity in a dose-dependent manner, with no clinical signs or discomfort from the virus infection regardless of the route of administration or the amount of virus

SUMO Ligase Protein Inhibitor of Activated STAT1 (PIAS1) Is a Constituent Promyelocytic Leukemia Nuclear Body Protein That Contributes to the Intrinsic Antiviral Immune Response to Herpes Simplex Virus 1.

Science.gov (United States)

Brown, James R; Conn, Kristen L; Wasson, Peter; Charman, Matthew; Tong, Lily; Grant, Kyle; McFarlane, Steven; Boutell, Chris

2016-07-01

Aspects of intrinsic antiviral immunity are mediated by promyelocytic leukemia nuclear body (PML-NB) constituent proteins. During herpesvirus infection, these antiviral proteins are independently recruited to nuclear domains that contain infecting viral genomes to cooperatively promote viral genome silencing. Central to the execution of this particular antiviral response is the small ubiquitin-like modifier (SUMO) signaling pathway. However, the participating SUMOylation enzymes are not fully characterized. We identify the SUMO ligase protein inhibitor of activated STAT1 (PIAS1) as a constituent PML-NB protein. We show that PIAS1 localizes at PML-NBs in a SUMO interaction motif (SIM)-dependent manner that requires SUMOylated or SUMOylation-competent PML. Following infection with herpes simplex virus 1 (HSV-1), PIAS1 is recruited to nuclear sites associated with viral genome entry in a SIM-dependent manner, consistent with the SIM-dependent recruitment mechanisms of other well-characterized PML-NB proteins. In contrast to that of Daxx and Sp100, however, the recruitment of PIAS1 is enhanced by PML. PIAS1 promotes the stable accumulation of SUMO1 at nuclear sites associated with HSV-1 genome entry, whereas the accumulation of other evaluated PML-NB proteins occurs independently of PIAS1. We show that PIAS1 cooperatively contributes to HSV-1 restriction through mechanisms that are additive to those of PML and cooperative with those of PIAS4. The antiviral mechanisms of PIAS1 are counteracted by ICP0, the HSV-1 SUMO-targeted ubiquitin ligase, which disrupts the recruitment of PIAS1 to nuclear domains that contain infecting HSV-1 genomes through mechanisms that do not directly result in PIAS1 degradation. Adaptive, innate, and intrinsic immunity cooperatively and efficiently restrict the propagation of viral pathogens. Intrinsic immunity mediated by constitutively expressed cellular proteins represents the first line of intracellular defense against infection. PML

EXPRESSION OF GLYCOPROTEIN gD AND EVALUATION OF IMMUNE RESPONSE OF BOVINE HERPES VIRUS TYPE-1 IN BUFFALO

Directory of Open Access Journals (Sweden)

Sumit Chowdhury

2012-12-01

Full Text Available Bovine Herpes Virus type-1 (BoHV-1 causes a multitude of clinical symptoms in cattle, buffaloes and small ruminants. No effective live attenuated or killed vaccine is currently available and extensive research work in progress towards the development of the subunit and genetically engineered vaccine. Since DNA vaccine is currently regarded as most important breakthrough in vaccinology, the present work was aimed at construction of DNA vaccine using most immunogenic glycoprotein gD and studying its immune response and protection in buffalo. gD specific DIG labelled probe was used to screen gD specific clones from cDNA library. The gD specific cloned plasmid was purified for eukaryotic expression. The SDS-PAGE & Western blot analysis showed the transient expression of the expected 71 kDa gD following transfection in COS-7 cells. Four seronegative buffalo calves were immunized at 0, 30 and 60 days with recombinant purified plasmid and two calves were kept as control. The result of SNT, ELISA and MTT indicate gene specific seroconversion and CMI response following immunization with plasmid. At 86 days of post first vaccination, animals were challenged with virulent BoHV-1 (216/IBR. Hematological picture of the control animals showed leucopenia and that was due to destruction of lymphocytes shown by TLC and apoptosis study. Vaccinated animals showed reduced virus shedding in terms of days post challenge as well as titers compared to the controls. Based on the above findings, we concluded that DNA based vaccine induces specific and protective immune responses to the buffalo.

The correlation between perceived social support and illness uncertainty in people with human immunodeficiency virus/acquired immune deficiency syndrome in Iran

Directory of Open Access Journals (Sweden)

Moosa Sajjadi

2015-01-01

Full Text Available Background: Illness uncertainty is a source of a chronic and pervasive psychological stress for people living with human immunodeficiency virus (HIV/acquired immune deficiency syndrome (AIDS (PLWH, and largely affects their quality of life and the ability to cope with the disease. Based on the uncertainty in illness theory, the social support is one of the illness uncertainty antecedents, and influences the level of uncertainty perceived by patients. Aim: To examine uncertainty in PLWH and its correlation with social support in Iran. Materials and Methods: This cross-sectional correlational study was conducted with 80 PLWH presenting to AIDS Research Center, Tehran, Iran in 2013. The data collected using illness uncertainty and social support inventories were analyzed through Pearson′s correlation coefficient, Spearman′s correlation coefficient, and regression analysis. Results: The results showed a high level of illness uncertainty in PLWH and a negative significant correlation between perceived social support and illness uncertainty ( P = 0.01, r = -0.29. Conclusion: Uncertainty is a serious aspect of illness experience in Iranian PLWH. Providing adequate, structured information to patients as well as opportunities to discuss their concerns with other PLWH and receive emotional support from their health care providers may be worthwhile.

High Mortality and Coinfection in a Prospective Cohort of Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome Patients with Histoplasmosis in Guatemala.

Science.gov (United States)

Samayoa, Blanca; Roy, Monika; Cleveland, Angela Ahlquist; Medina, Narda; Lau-Bonilla, Dalia; Scheel, Christina M; Gomez, Beatriz L; Chiller, Tom; Arathoon, Eduardo

2017-07-01

Histoplasmosis is one of the most common and deadly opportunistic infections among persons living with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome in Latin America, but due to limited diagnostic capacity in this region, few data on the burden and clinical characteristics of this disease exist. Between 2005 and 2009, we enrolled patients ≥ 18 years of age with suspected histoplasmosis at a hospital-based HIV clinic in Guatemala City. A case of suspected histoplasmosis was defined as a person presenting with at least three of five clinical or radiologic criteria. A confirmed case of histoplasmosis was defined as a person with a positive culture or urine antigen test for Histoplasma capsulatum . Demographic and clinical data were also collected and analyzed. Of 263 enrolled as suspected cases of histoplasmosis, 101 (38.4%) were confirmed cases. Median time to diagnosis was 15 days after presentation (interquartile range [IQR] = 5-23). Crude overall mortality was 43.6%; median survival time was 19 days (IQR = 4-69). Mycobacterial infection was diagnosed in 70 (26.6%) cases; 26 (25.7%) histoplasmosis cases were coinfected with mycobacteria. High mortality and short survival time after initial symptoms were observed in patients with histoplasmosis. Mycobacterial coinfection diagnoses were frequent, highlighting the importance of pursuing diagnoses for both diseases.

Expression of microRNAs and innate immune factor genes in lung tissue of pigs infected with influenza virus (H1N2)

DEFF Research Database (Denmark)

Skovgaard, Kerstin; Cirera, S.; Vasby, D.

A infection. The present work aimed of providing a better understanding of the involvement of innate immune factors including miRNA in the host response to establishment and progression of influenza virus infection. Twenty pigs were challenged by aerosol containing H1N2 (A/swine/Denmark/12687/03) influenza......Swine influenza is a highly infectious respiratory disease in pigs caused by influenza A virus. Activation of a frontline of pattern-recognition receptors (PRRs) expressed by epithelial cells as well as immune cells of the upper respiratory tract, leads to a potent type 1 interferon (IFN) release......, this response must be tightly regulated. Recently, microRNA (miRNA) has been proposed to play an important role in modulating and fine tuning the innate immune response in order to avoid such harmful overreactions. Little is known about the significance of miRNA regulation in the lung during acute influenza...

DNA Tumor Virus Regulation of Host DNA Methylation and Its Implications for Immune Evasion and Oncogenesis.

Science.gov (United States)

Kuss-Duerkop, Sharon K; Westrich, Joseph A; Pyeon, Dohun

2018-02-13

Viruses have evolved various mechanisms to evade host immunity and ensure efficient viral replication and persistence. Several DNA tumor viruses modulate host DNA methyltransferases for epigenetic dysregulation of immune-related gene expression in host cells. The host immune responses suppressed by virus-induced aberrant DNA methylation are also frequently involved in antitumor immune responses. Here, we describe viral mechanisms and virus-host interactions by which DNA tumor viruses regulate host DNA methylation to evade antiviral immunity, which may contribute to the generation of an immunosuppressive microenvironment during cancer development. Recent trials of immunotherapies have shown promising results to treat multiple cancers; however, a significant number of non-responders necessitate identifying additional targets for cancer immunotherapies. Thus, understanding immune evasion mechanisms of cancer-causing viruses may provide great insights for reversing immune suppression to prevent and treat associated cancers.

Gamma-irradiated influenza A virus can prime for a cross-reactive and cross-protective immune response against influenza A viruses

International Nuclear Information System (INIS)

Mullbacher, A.; Ada, G.L.; Tha Hla, R.

1988-01-01

A-strain influenza virus A/JAP (H2N2) was tested for its ability to induce cytotoxic T cells (Tc) after being rendered non-infectious by either UV or gamma irradiation. Gamma-irradiated virus proved to be more efficient than UV-inactivated virus in priming for a memory Tc cell response or in boosting memory spleen cells in vitro. Most importantly, γ-inactivated, but not UV-inactivated, A/JAP immunized animals survived lethal challenge with heterologous (A/PC(H3N2), A/WSN(H1N1)) virus as effectively as mice primed with infectious virus

Sequential immunization with V3 peptides from primary human immunodeficiency virus type 1 produces cross-neutralizing antibodies against primary isolates with a matching narrow-neutralization sequence motif.

Science.gov (United States)

Eda, Yasuyuki; Takizawa, Mari; Murakami, Toshio; Maeda, Hiroaki; Kimachi, Kazuhiko; Yonemura, Hiroshi; Koyanagi, Satoshi; Shiosaki, Kouichi; Higuchi, Hirofumi; Makizumi, Keiichi; Nakashima, Toshihiro; Osatomi, Kiyoshi; Tokiyoshi, Sachio; Matsushita, Shuzo; Yamamoto, Naoki; Honda, Mitsuo

2006-06-01

An antibody response capable of neutralizing not only homologous but also heterologous forms of the CXCR4-tropic human immunodeficiency virus type 1 (HIV-1) MNp and CCR5-tropic primary isolate HIV-1 JR-CSF was achieved through sequential immunization with a combination of synthetic peptides representing HIV-1 Env V3 sequences from field and laboratory HIV-1 clade B isolates. In contrast, repeated immunization with a single V3 peptide generated antibodies that neutralized only type-specific laboratory-adapted homologous viruses. To determine whether the cross-neutralization response could be attributed to a cross-reactive antibody in the immunized animals, we isolated a monoclonal antibody, C25, which neutralized the heterologous primary viruses of HIV-1 clade B. Furthermore, we generated a humanized monoclonal antibody, KD-247, by transferring the genes of the complementary determining region of C25 into genes of the human V region of the antibody. KD-247 bound with high affinity to the "PGR" motif within the HIV-1 Env V3 tip region, and, among the established reference antibodies, it most effectively neutralized primary HIV-1 field isolates possessing the matching neutralization sequence motif, suggesting its promise for clinical applications involving passive immunizations. These results demonstrate that sequential immunization with B-cell epitope peptides may contribute to a humoral immune-based HIV vaccine strategy. Indeed, they help lay the groundwork for the development of HIV-1 vaccine strategies that use sequential immunization with biologically relevant peptides to overcome difficulties associated with otherwise poorly immunogenic epitopes.

Risky sexual behaviour and human immunodeficiency virus (HIV and acquired immune deficiency syndrome (AIDS among healthcare workers

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Natasha Khamisa

2018-01-01

Full Text Available Background: South Africa is known to have one of the highest prevalence rates of human immunodeficiency virus (HIV and acquired immune deficiency syndrome (AIDS globally, with one in seven healthcare workers being HIV-positive. An HIV-positive healthcare workforce is less equipped to respond to the increasing spread of the epidemic. Objectives: Assessment of the factors contributing to high HIV prevalence rates among healthcare workers is important in planning the development of human resources. This review sought to identify and understand predominant risky sexual behaviours among healthcare workers in HIV and AIDS-affected countries. Methods: This study reviewed articles focusing on sexual behaviour among healthcare workers. Major health science databases (e.g. ProQuest, Cochrane, PubMed and CINAHL were searched for combinations of keywords including ‘healthcare workers’, ‘risky sexual behaviour’ and ‘HIV and AIDS’. Articles from a range of countries met inclusion and exclusion criteria. Results: Findings of the study revealed three main contributing factors: unprotected sex, multiple sex partners and sexual violence. Sexual violence emerged as the dominant risk factor in the majority of the studies. Most research was conducted in developed countries where the HIV infection rate is much lower than it is in developing countries. Conclusion: More research needs to be conducted in developing countries and appropriate strategies should be implemented to reduce sexual violence among healthcare workers. Appropriate procedures on reporting sexual violence coupled with education on HIV and AIDS as well as influencing attitudes and belief systems could assist in reducing the spread of HIV and AIDS within the healthcare workforce while minimising the effect on patient care.

A study of some aspects of auto immunity in children with thalassemia major

International Nuclear Information System (INIS)

El Adham, E.K

2008-01-01

This study is subjected to estimate the study of the most common autoimmune complications in thalassemia and the prevalence of different auto antibodies so as to evaluate its correlation with personal data including age, sex, growth parameters, Hepatitis C virus infection ferritin level and type of iron chelation therapy methodology : Different Abs including anti cardiolipin, antitistone, ANA, Anti erythropoietin by ELISA technique Hepatitis C virus by ELISA. Ferritin by IRMA (Immune radiometric assay), Protein C, S. Antithrombin III by ELISA result of the study were analyzed by appropriate statistical methods .The results showed that age of Hepatitis C virus negative cases was significantly lower than Hepatitis C virus Positive cases, ferritin levels were significantly higher in patients on defripone than those as desferrioxamine, anti erythropoietin was detected in 93.3% of cases regarding the antithrombotic factors deficiency. Protein C was deficient in 26.67% of cases. Protein S was deficient in 13.33% only and no cases showed anti thrombin III deficiency. No special relation was found between these abnormalities and type of chelation , Conclusions: Auto immunity may be a cofactor in the development of life threatening complication

Expression of H5 hemagglutinin vaccine antigen in common duckweed (Lemna minor) protects against H5N1 high pathogenicity avian influenza virus challenge in immunized chickens.

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Bertran, Kateri; Thomas, Colleen; Guo, Xuan; Bublot, Michel; Pritchard, Nikki; Regan, Jeffrey T; Cox, Kevin M; Gasdaska, John R; Dickey, Lynn F; Kapczynski, Darrell R; Swayne, David E

2015-07-09

A synthetic hemagglutinin (HA) gene from the highly pathogenic avian influenza (HPAI) virus A/chicken/Indonesia/7/2003 (H5N1) (Indo/03) was expressed in aquatic plant Lemna minor (rLemna-HA). In Experiment 1, efficacy of rLemna-HA was tested on birds immunized with 0.2μg or 2.3 μg HA and challenged with 10(6) mean chicken embryo infectious doses (EID50) of homologous virus strain. Both dosages of rLemna-HA conferred clinical protection and dramatically reduced viral shedding. Almost all the birds immunized with either dosage of rLemna-HA elicited HA antibody titers against Indo/03 antigen, suggesting an association between levels of anti-Indo/03 antibodies and protection. In Experiment 2, efficacy of rLemna-HA was tested on birds immunized with 0.9 μg or 2.2 μg HA and challenged with 10(6) EID50 of heterologous H5N1 virus strains A/chicken/Vietnam/NCVD-421/2010 (VN/10) or A/chicken/West Java/PWT-WIJ/2006 (PWT/06). Birds challenged with VN/10 exhibited 100% survival regardless of immunization dosage, while birds challenged with PWT/06 had 50% and 30% mortality at 0.9 μg HA and 2.2 μg HA, respectively. For each challenge virus, viral shedding titers from 2.2 μg HA vaccinated birds were significantly lower than those from 0.9μg HA vaccinated birds, and titers from both immunized groups were in turn significantly lower than those from sham vaccinated birds. Even if immunized birds elicited HA titers against the vaccine antigen Indo/03, only the groups challenged with VN/10 developed humoral immunity against the challenge antigen. None (rLemna-HA 0.9 μg HA) and 40% (rLemna-HA 2.2 μg HA) of the immunized birds challenged with PWT/06 elicited pre-challenge antibody titers, respectively. In conclusion, Lemna-expressed HA demonstrated complete protective immunity against homologous challenge and suboptimal protection against heterologous challenge, the latter being similar to results from inactivated whole virus vaccines. Transgenic duckweed-derived HA could be a

Induction of ebolavirus cross-species immunity using retrovirus-like particles bearing the Ebola virus glycoprotein lacking the mucin-like domain

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Ou Wu

2012-01-01

Full Text Available Abstract Background The genus Ebolavirus includes five distinct viruses. Four of these viruses cause hemorrhagic fever in humans. Currently there are no licensed vaccines for any of them; however, several vaccines are under development. Ebola virus envelope glycoprotein (GP1,2 is highly immunogenic, but antibodies frequently arise against its least conserved mucin-like domain (MLD. We hypothesized that immunization with MLD-deleted GP1,2 (GPΔMLD would induce cross-species immunity by making more conserved regions accessible to the immune system. Methods To test this hypothesis, mice were immunized with retrovirus-like particles (retroVLPs bearing Ebola virus GPΔMLD, DNA plasmids (plasmo-retroVLP that can produce such retroVLPs in vivo, or plasmo-retroVLP followed by retroVLPs. Results Cross-species neutralizing antibody and GP1,2-specific cellular immune responses were successfully induced. Conclusion Our findings suggest that GPΔMLD presented through retroVLPs may provide a strategy for development of a vaccine against multiple ebolaviruses. Similar vaccination strategies may be adopted for other viruses whose envelope proteins contain highly variable regions that may mask more conserved domains from the immune system.

EBNA1: Oncogenic Activity, Immune Evasion and Biochemical Functions Provide Targets for Novel Therapeutic Strategies against Epstein-Barr Virus- Associated Cancers

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Joanna B. Wilson

2018-04-01

Full Text Available The presence of the Epstein-Barr virus (EBV-encoded nuclear antigen-1 (EBNA1 protein in all EBV-carrying tumours constitutes a marker that distinguishes the virus-associated cancer cells from normal cells and thereby offers opportunities for targeted therapeutic intervention. EBNA1 is essential for viral genome maintenance and also for controlling viral gene expression and without EBNA1, the virus cannot persist. EBNA1 itself has been linked to cell transformation but the underlying mechanism of its oncogenic activity has been unclear. However, recent data are starting to shed light on its growth-promoting pathways, suggesting that targeting EBNA1 can have a direct growth suppressing effect. In order to carry out its tasks, EBNA1 interacts with cellular factors and these interactions are potential therapeutic targets, where the aim would be to cripple the virus and thereby rid the tumour cells of any oncogenic activity related to the virus. Another strategy to target EBNA1 is to interfere with its expression. Controlling the rate of EBNA1 synthesis is critical for the virus to maintain a sufficient level to support viral functions, while at the same time, restricting expression is equally important to prevent the immune system from detecting and destroying EBNA1-positive cells. To achieve this balance EBNA1 has evolved a unique repeat sequence of glycines and alanines that controls its own rate of mRNA translation. As the underlying molecular mechanisms for how this repeat suppresses its own rate of synthesis in cis are starting to be better understood, new therapeutic strategies are emerging that aim to modulate the translation of the EBNA1 mRNA. If translation is induced, it could increase the amount of EBNA1-derived antigenic peptides that are presented to the major histocompatibility (MHC class I pathway and thus, make EBV-carrying cancers better targets for the immune system. If translation is further suppressed, this would provide another

A prime-boost vaccination strategy using attenuated Salmonella typhimurium and a replication-deficient recombinant adenovirus vector elicits protective immunity against human respiratory syncytial virus.

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Fu, Yuan-Hui; He, Jin-Sheng; Wang, Xiao-Bo; Zheng, Xian-Xian; Wu, Qiang; Xie, Can; Zhang, Mei; Wei, Wei; Tang, Qian; Song, Jing-Dong; Qu, Jian-Guo; Hong, Tao

2010-04-23

Human respiratory syncytial virus (RSV), for which no clinically approved vaccine is available yet, is globally a serious pediatric pathogen of the lower respiratory tract. Several approaches have been used to develop vaccines against RSV, but none of these have been approved for use in humans. An efficient vaccine-enhancing strategy for RSV is still urgently needed. We found previously that oral SL7207/pcDNA3.1/F and intranasal FGAd/F were able to induce an effective protective immune response against RSV. The heterologous prime-boost immunization regime has been reported recently to be an efficient vaccine-enhancing strategy. Therefore, we investigated the ability of an oral SL7207/pcDNA3.1/F prime and intranasal (i.n.) FGAd/F boost regimen to generate immune responses to RSV. The SL7207/pcDNA3.1/F prime-FGAd/F boost regimen generated stronger RSV-specific humoral and mucosal immune responses in BALB/c mice than the oral SL7207/pcDNA3.1/F regimen alone, and stronger specific cellular immune responses than the i.n. FGAd/F regimen alone. Histopathological analysis showed an increased efficacy against RSV challenge by the heterologous prime-boost regimen. These results suggest that such a heterologous prime-boost strategy can enhance the efficacy of either the SL7207 or the FGAd vector regimen in generating immune responses in BALB/c mice. 2010 Elsevier Inc. All rights reserved.

Human and Mouse Eosinophils Have Antiviral Activity against Parainfluenza Virus.

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Drake, Matthew G; Bivins-Smith, Elizabeth R; Proskocil, Becky J; Nie, Zhenying; Scott, Gregory D; Lee, James J; Lee, Nancy A; Fryer, Allison D; Jacoby, David B

2016-09-01

Respiratory viruses cause asthma exacerbations. Because eosinophils are the prominent leukocytes in the airways of 60-70% of patients with asthma, we evaluated the effects of eosinophils on a common respiratory virus, parainfluenza 1, in the lung. Eosinophils recruited to the airways of wild-type mice after ovalbumin sensitization and challenge significantly decreased parainfluenza virus RNA in the lungs 4 days after infection compared with nonsensitized animals. This antiviral effect was also seen in IL-5 transgenic mice with an abundance of airway eosinophils (NJ.1726) but was lost in transgenic eosinophil-deficient mice (PHIL) and in IL-5 transgenic mice crossed with eosinophil-deficient mice (NJ.1726-PHIL). Loss of the eosinophil granule protein eosinophil peroxidase, using eosinophil peroxidase-deficient transgenic mice, did not reduce eosinophils' antiviral effect. Eosinophil antiviral mechanisms were also explored in vitro. Isolated human eosinophils significantly reduced parainfluenza virus titers. This effect did not involve degradation of viral RNA by eosinophil granule RNases. However, eosinophils treated with a nitric oxide synthase inhibitor lost their antiviral activity, suggesting eosinophils attenuate viral infectivity through production of nitric oxide. Consequently, eosinophil nitric oxide production was measured with an intracellular fluorescent probe. Eosinophils produced nitric oxide in response to virus and to a synthetic agonist of the virus-sensing innate immune receptor, Toll-like receptor (TLR) 7. IFNγ increased expression of eosinophil TLR7 and potentiated TLR7-induced nitric oxide production. These results suggest that eosinophils promote viral clearance in the lung and contribute to innate immune responses against respiratory virus infections in humans.

Analysis of immune-related genes during Nora virus infection of Drosophila melanogaster using next generation sequencing.

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Lopez, Wilfredo; Page, Alexis M; Carlson, Darby J; Ericson, Brad L; Cserhati, Matyas F; Guda, Chittibabu; Carlson, Kimberly A

2018-01-01

Drosophila melanogaster depends upon the innate immune system to regulate and combat viral infection. This is a complex, yet widely conserved process that involves a number of immune pathways and gene interactions. In addition, expression of genes involved in immunity are differentially regulated as the organism ages. This is particularly true for viruses that demonstrate chronic infection, as is seen with Nora virus. Nora virus is a persistent non-pathogenic virus that replicates in a horizontal manner in D. melanogaster . The genes involved in the regulation of the immune response to Nora virus infection are largely unknown. In addition, the temporal response of immune response genes as a result of infection has not been examined. In this study, D. melanogaster either infected with Nora virus or left uninfected were aged for 2, 10, 20 and 30 days. The RNA from these samples was analyzed by next generation sequencing (NGS) and the resulting immune-related genes evaluated by utilizing both the PANTHER and DAVID databases, as well as comparison to lists of immune related genes and FlyBase. The data demonstrate that Nora virus infected D. melanogaster exhibit an increase in immune related gene expression over time. In addition, at day 30, the data demonstrate that a persistent immune response may occur leading to an upregulation of specific immune response genes. These results demonstrate the utility of NGS in determining the potential immune system genes involved in Nora virus replication, chronic infection and involvement of antiviral pathways.

Morbillivirus control of the interferon response: relevance of STAT2 and mda5 but not STAT1 for canine distemper virus virulence in ferrets.

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Svitek, Nicholas; Gerhauser, Ingo; Goncalves, Christophe; Grabski, Elena; Döring, Marius; Kalinke, Ulrich; Anderson, Danielle E; Cattaneo, Roberto; von Messling, Veronika

2014-03-01

The V proteins of paramyxoviruses control the innate immune response. In particular, the V protein of the genus Morbillivirus interferes with the signal transducer and activator of transcription 1 (STAT1), STAT2, and melanoma differentiation-associated protein 5 (mda5) signaling pathways. To characterize the contributions of these pathways to canine distemper virus (CDV) pathogenesis, we took advantage of the knowledge about the mechanisms of interaction between the measles virus V protein with these key regulators of innate immunity. We generated recombinant CDVs with V proteins unable to properly interact with STAT1, STAT2, or mda5. A virus with combined STAT2 and mda5 deficiencies was also generated, and available wild-type and V-protein-knockout viruses were used as controls. Ferrets infected with wild-type and STAT1-blind viruses developed severe leukopenia and loss of lymphocyte proliferation activity and succumbed to the disease within 14 days. In contrast, animals infected with viruses with STAT2 or mda5 defect or both STAT2 and mda5 defects developed a mild self-limiting disease similar to that associated with the V-knockout virus. This study demonstrates the importance of interference with STAT2 and mda5 signaling for CDV immune evasion and provides a starting point for the development of morbillivirus vectors with reduced immunosuppressive properties. The V proteins of paramyxoviruses interfere with the recognition of the virus by the immune system of the host. For morbilliviruses, the V protein is known to interact with the signal transducer and activator of transcription 1 (STAT1) and STAT2 and the melanoma differentiation-associated protein 5 (mda5), which are involved in interferon signaling. Here, we examined the contribution of each of these signaling pathways to the pathogenesis of the carnivore morbillivirus canine distemper virus. Using viruses selectively unable to interfere with the respective signaling pathway to infect ferrets, we found that

Sequential analysis of the virus-immune responder characteristics of thymocytes from F1→parent radiation chimeras

International Nuclear Information System (INIS)

Korngold, R.; Doherty, P.C.

1982-01-01

The virus-immune responder characteristics of thymocytes, spleen and lymph node (LN) cells from (P 1 x P 2 )F 1 →P 1 radiation chimeras have been examined sequentially at weekly intervals. Adoptively-transferred thymocytes generate strong cytotoxic thymus-derived lymphocyte (CTL) responses from 28 to 100 days after reconstitution with bone marrow, which are almost invariably restricted to recognition of virus presented in the context of P 1 . This pattern of H-2 restriction is also maintained for spleen and LN cells from the [(H-2sup(kxd)F 1 →H-2sup(k)] and [(H-2sup(kxb)F 1 →H-2sup(k)] combinations but there is random emergence of reactivity to H-2sup(k)+virus for peripheral lymphoid cells from [(H-2sup(kxb)F 1 →H-2sup(b)] chimeras. Treatment of established [(P 1 xP 2 )]F 1 →P 1 ] chimeras with a low dose of cyclophosphamide (Cy) did not lead to the emergence of significant CTL effector function for P2 + virus. Also, administration of a large dose of Cy prior to irradiation of the chimera recipients did not modify the H-2 restriction profile of the chimera, though the level of CTL responsiveness associated with the appropriate H-2 type was apparently enhanced. (Auth.)

Functional genomics reveals an essential and specific role for Stat1 in protection of the central nervous system following herpes simplex virus corneal infection.

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Pasieka, Tracy Jo; Cilloniz, Cristian; Carter, Victoria S; Rosato, Pamela; Katze, Michael G; Leib, David A

2011-12-01

Innate immune deficiencies result in a spectrum of severe clinical outcomes following infection. In particular, there is a strong association between loss of the signal transducer and activator of transcription (Stat) pathway, breach of the blood-brain barrier (BBB), and virus-induced neuropathology. The gene signatures that characterize resistance, disease, and mortality in the virus-infected nervous system have not been defined. Herpes simplex virus type 1 (HSV-1) is commonly associated with encephalitis in humans, and humans and mice lacking Stat1 display increased susceptibility to HSV central nervous system (CNS) infections. In this study, two HSV-1 strains were used, KOS (wild type [WT]), and Δvhs, an avirulent recombinant lacking the virion host shutoff (vhs) function. In addition, two mouse strains were used: strain 129 (control) and a Stat1-deficient (Stat1(-/-)) strain. Using combinations of these virus and mouse strains, we established a model of infection resulting in three different outcomes: viral clearance without neurological disease (Δvhs infection of control mice), neurological disease followed by viral clearance (Δvhs infection of Stat1(-/-) mice and WT infection of control mice), or neurological disease followed by death (WT infection of Stat1(-/-) mice). Through the use of functional genomics on the infected brain stems, we determined gene signatures that were representative of the three infection outcomes. We demonstrated a pathological signature in the brain stem of Stat1-deficient mice characterized by upregulation of transcripts encoding chemokine receptors, inflammatory markers, neutrophil chemoattractants, leukocyte adhesion proteins, and matrix metalloproteases. Additionally, there was a greater than 100-fold increase in the inflammatory markers interleukin 1β (IL-1β) and IL-6. Consistent with this gene signature, we demonstrated profound CNS inflammation with a concomitant lethal breach of the BBB. Taken together, our results

Induction of human immunodeficiency virus (HIV-1 envelope specific cell-mediated immunity by a non-homologous synthetic peptide.

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Ammar Achour

2007-11-01

Full Text Available Cell mediated immunity, including efficient CTL response, is required to prevent HIV-1 from cell-to-cell transmission. In previous investigations, we have shown that B1 peptide derived by Fourier transformation of HIV-1 primary structures and sharing no sequence homology with the parent proteins was able to generate antiserum which recognizes envelope and Tat proteins. Here we have investigated cellular immune response towards a novel non-homologous peptide, referred to as cA1 peptide.The 20 amino acid sequence of cA1 peptide was predicted using the notion of peptide hydropathic properties; the peptide is encoded by the complementary anti-sense DNA strand to the sense strand of previously described non-homologous A1 peptide. In this report we demonstrate that the cA1 peptide can be a target for major histocompatibility complex (MHC class I-restricted cytotoxic T lymphocytes in HIV-1-infected or envelope-immunized individuals. The cA1 peptide is recognized in association with different MHC class I allotypes and could prime in vitro CTLs, derived from gp160-immunized individuals capable to recognize virus variants.For the first time a theoretically designed immunogen involved in broad-based cell-immune memory activation is described. Our findings may thus contribute to the advance in vaccine research by describing a novel strategy to develop a synthetic AIDS vaccine.

DNA Tumor Virus Regulation of Host DNA Methylation and Its Implications for Immune Evasion and Oncogenesis

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Sharon K. Kuss-Duerkop

2018-02-01

Full Text Available Viruses have evolved various mechanisms to evade host immunity and ensure efficient viral replication and persistence. Several DNA tumor viruses modulate host DNA methyltransferases for epigenetic dysregulation of immune-related gene expression in host cells. The host immune responses suppressed by virus-induced aberrant DNA methylation are also frequently involved in antitumor immune responses. Here, we describe viral mechanisms and virus–host interactions by which DNA tumor viruses regulate host DNA methylation to evade antiviral immunity, which may contribute to the generation of an immunosuppressive microenvironment during cancer development. Recent trials of immunotherapies have shown promising results to treat multiple cancers; however, a significant number of non-responders necessitate identifying additional targets for cancer immunotherapies. Thus, understanding immune evasion mechanisms of cancer-causing viruses may provide great insights for reversing immune suppression to prevent and treat associated cancers.

Nutritional zinc deficiency, immune capacity and malaria : a study on mediators of immunity to malaria caused by Plasmodium falciparum in African children

NARCIS (Netherlands)

Mbugi, E.V.

2009-01-01

This thesis aimed at investigating the role of genetic and nutritional factors that affect the immune response to malaria in Tanzanian children. The introductory chapter (Chapter 1) reviews the importance of nutritional deficiencies, particularly of zinc, and presents the hypothesis that such

Evidence of cross-reactive immunity to 2009 pandemic influenza A virus in workers seropositive to swine H1N1 influenza viruses circulating in Italy.

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Maria A De Marco

Full Text Available BACKGROUND: Pigs play a key epidemiologic role in the ecology of influenza A viruses (IAVs emerging from animal hosts and transmitted to humans. Between 2008 and 2010, we investigated the health risk of occupational exposure to swine influenza viruses (SIVs in Italy, during the emergence and spread of the 2009 H1N1 pandemic (H1N1pdm virus. METHODOLOGY/PRINCIPAL FINDINGS: Serum samples from 123 swine workers (SWs and 379 control subjects (Cs, not exposed to pig herds, were tested by haemagglutination inhibition (HI assay against selected SIVs belonging to H1N1 (swH1N1, H1N2 (swH1N2 and H3N2 (swH3N2 subtypes circulating in the study area. Potential cross-reactivity between swine and human IAVs was evaluated by testing sera against recent, pandemic and seasonal, human influenza viruses (H1N1 and H3N2 antigenic subtypes. Samples tested against swH1N1 and H1N1pdm viruses were categorized into sera collected before (n. 84 SWs; n. 234 Cs and after (n. 39 SWs; n. 145 Cs the pandemic peak. HI-antibody titers ≥10 were considered positive. In both pre-pandemic and post-pandemic peak subperiods, SWs showed significantly higher swH1N1 seroprevalences when compared with Cs (52.4% vs. 4.7% and 59% vs. 9.7%, respectively. Comparable HI results were obtained against H1N1pdm antigen (58.3% vs. 7.7% and 59% vs. 31.7%, respectively. No differences were found between HI seroreactivity detected in SWs and Cs against swH1N2 (33.3% vs. 40.4% and swH3N2 (51.2 vs. 55.4% viruses. These findings indicate the occurrence of swH1N1 transmission from pigs to Italian SWs. CONCLUSION/SIGNIFICANCE: A significant increase of H1N1pdm seroprevalences occurred in the post-pandemic peak subperiod in the Cs (p<0.001 whereas SWs showed no differences between the two subperiods, suggesting a possible occurrence of cross-protective immunity related to previous swH1N1 infections. These data underline the importance of risk assessment and occupational health surveillance activities aimed

A quantitative quasispecies theory-based model of virus escape mutation under immune selection.

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Woo, Hyung-June; Reifman, Jaques

2012-08-07

Viral infections involve a complex interplay of the immune response and escape mutation of the virus quasispecies inside a single host. Although fundamental aspects of such a balance of mutation and selection pressure have been established by the quasispecies theory decades ago, its implications have largely remained qualitative. Here, we present a quantitative approach to model the virus evolution under cytotoxic T-lymphocyte immune response. The virus quasispecies dynamics are explicitly represented by mutations in the combined sequence space of a set of epitopes within the viral genome. We stochastically simulated the growth of a viral population originating from a single wild-type founder virus and its recognition and clearance by the immune response, as well as the expansion of its genetic diversity. Applied to the immune escape of a simian immunodeficiency virus epitope, model predictions were quantitatively comparable to the experimental data. Within the model parameter space, we found two qualitatively different regimes of infectious disease pathogenesis, each representing alternative fates of the immune response: It can clear the infection in finite time or eventually be overwhelmed by viral growth and escape mutation. The latter regime exhibits the characteristic disease progression pattern of human immunodeficiency virus, while the former is bounded by maximum mutation rates that can be suppressed by the immune response. Our results demonstrate that, by explicitly representing epitope mutations and thus providing a genotype-phenotype map, the quasispecies theory can form the basis of a detailed sequence-specific model of real-world viral pathogens evolving under immune selection.

Antagonism of the Phosphatase PP1 by the Measles Virus V Protein Is Required for Innate Immune Escape of MDA5

NARCIS (Netherlands)

Davis, Meredith E.; Wang, May K.; Rennick, Linda J.; Full, Florian; Gableske, Sebastian; Mesman, Annelies W.; Gringhuis, Sonja I.; Geijtenbeek, Teunis B. H.; Duprex, W. Paul; Gack, Michaela U.

2014-01-01

The cytosolic sensor MDA5 is crucial for antiviral innate immune defense against various RNA viruses including measles virus; as such, many viruses have evolved strategies to antagonize the antiviral activity of MDA5. Here, we show that measles virus escapes MDA5 detection by targeting the

Humoral immune response to hypervariable region 1 of the putative envelope glycoprotein (gp70) of hepatitis C virus.

OpenAIRE

Kato, N; Sekiya, H; Ootsuyama, Y; Nakazawa, T; Hijikata, M; Ohkoshi, S; Shimotohno, K

1993-01-01

We recently found that alterations of amino acids in hypervariable region 1 (HVR1) of the putative envelope glycoprotein (gp70) of hepatitis C virus (HCV) occurred sequentially in the chronic phase of hepatitis at intervals of several months. This finding suggests that mutations in HVR1 are involved in the mechanism of persistent chronic HCV infection involving escape from the immunosurveillance system. To explore this possibility, we examined the humoral immune response to HVR1 with our assa...

Protection of pigs against pandemic swine origin H1N1 influenza A virus infection by hemagglutinin- or neuraminidase-expressing attenuated pseudorabies virus recombinants.

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Klingbeil, Katharina; Lange, Elke; Blohm, Ulrike; Teifke, Jens P; Mettenleiter, Thomas C; Fuchs, Walter

2015-03-02

Influenza is an important respiratory disease of pigs, and may lead to novel human pathogens like the 2009 pandemic H1N1 swine-origin influenza virus (SoIV). Therefore, improved influenza vaccines for pigs are required. Recently, we demonstrated that single intranasal immunization with a hemagglutinin (HA)-expressing pseudorabies virus recombinant of vaccine strain Bartha (PrV-Ba) protected pigs from H1N1 SoIV challenge (Klingbeil et al., 2014). Now we investigated enhancement of efficacy by prime-boost vaccination and/or intramuscular administration. Furthermore, a novel PrV-Ba recombinant expressing codon-optimized N1 neuraminidase (NA) was included. In vitro replication of this virus was only slightly affected compared to parental virus. Unlike HA, the abundantly expressed NA was efficiently incorporated into PrV particles. Immunization of pigs with the two PrV recombinants, either singly or in combination, induced B cell proliferation and the expected SoIV-specific antibodies, whose titers increased substantially after boost vaccination. After immunization of animals with either PrV recombinant H1N1 SoIV challenge virus replication was significantly reduced compared to PrV-Ba vaccinated or naïve controls. Protective efficacy of HA-expressing PrV was higher than of NA-expressing PrV, and not significantly enhanced by combination. Despite higher serum antibody titers obtained after intramuscular immunization, transmission of challenge virus to naïve contact animals was only prevented after intranasal prime-boost vaccination with HA-expressing PrV-Ba. Copyright © 2015 Elsevier B.V. All rights reserved.

Studies on immune responses to Epstein-Barr virus among A-bomb survivors

International Nuclear Information System (INIS)

Kusunoki, Y.; Kyoizumi, S.; Ozaki, K.; Cologne, J.B.; Akiyama, M.

1992-01-01

Previous studies revealed that reactivity of T-lymphocytes to phytohemag-glutinin and allo-antigens as well as the number of mature CD5 + T cells are decreased among atomic bomb survivors. Possible radiation effects were suggested for impairment of antibody production to certain type A influenza viruses and for an increased prevalence rate of hepatitis B virus surface antigen in sera among survivors. These findings lead to research of effects of A-bomb radiation on immune responses to certain ubiquitous viruses such as Epstein-Barr Virus. Reactivation of EBV induced by depression of immune competence might be reflected by changes in serum titers of these antibodies. Significant increases in titers of antiviral capsed antigen IgC or anti-early antigen (EA) IgC and frequent absence o.r low levels of anti- EBV-associated nuclear antigen antibodies were observed in immunologically compromised individuals. Without regard to diseases, occurrence of significant titers of anti-EA IgC in healthy sero-positive individuals has been ascribed to reactivation of the viral carrier stage. This study examines serum titers of these anti-EBV antibodies to investigate whether any alteration of immune competence to the virus was detectable in relation to the previous A-bomb radiation exposure. Also, an attempt was made to evaluated T-cell responses to EBV in A-bomb survivors for the purpose of understanding involvement of T-cell function in reactivation of the virus, using the precursor frequency analysis of cytotoxic lymphocytes against autologous B cell transformed in vitro with EBV. (author). 13 refs., 2 figs., 1 tab

Expression of DAI by an oncolytic vaccinia virus boosts the immunogenicity of the virus and enhances antitumor immunity

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Mari Hirvinen

2016-01-01

Full Text Available In oncolytic virotherapy, the ability of the virus to activate the immune system is a key attribute with regard to long-term antitumor effects. Vaccinia viruses bear one of the strongest oncolytic activities among all oncolytic viruses. However, its capacity for stimulation of antitumor immunity is not optimal, mainly due to its immunosuppressive nature. To overcome this problem, we developed an oncolytic VV that expresses intracellular pattern recognition receptor DNA-dependent activator of IFN-regulatory factors (DAI to boost the innate immune system and to activate adaptive immune cells in the tumor. We showed that infection with DAI-expressing VV increases expression of several genes related to important immunological pathways. Treatment with DAI-armed VV resulted in significant reduction in the size of syngeneic melanoma tumors in mice. When the mice were rechallenged with the same tumor, DAI-VV-treated mice completely rejected growth of the new tumor, which indicates immunity established against the tumor. We also showed enhanced control of growth of human melanoma tumors and elevated levels of human T-cells in DAI-VV-treated mice humanized with human peripheral blood mononuclear cells. We conclude that expression of DAI by an oncolytic VV is a promising way to amplify the vaccine potency of an oncolytic vaccinia virus to trigger the innate—and eventually the long-lasting adaptive immunity against cancer.

Cold-adapted influenza and recombinant adenovirus vaccines induce cross-protective immunity against pH1N1 challenge in mice.

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Mark R Soboleski

Full Text Available The rapid spread of the 2009 H1N1 pandemic influenza virus (pH1N1 highlighted problems associated with relying on strain-matched vaccines. A lengthy process of strain identification, manufacture, and testing is required for current strain-matched vaccines and delays vaccine availability. Vaccines inducing immunity to conserved viral proteins could be manufactured and tested in advance and provide cross-protection against novel influenza viruses until strain-matched vaccines became available. Here we test two prototype vaccines for cross-protection against the recent pandemic virus.BALB/c and C57BL/6 mice were intranasally immunized with a single dose of cold-adapted (ca influenza viruses from 1977 or recombinant adenoviruses (rAd expressing 1934 nucleoprotein (NP and consensus matrix 2 (M2 (NP+M2-rAd. Antibodies against the M2 ectodomain (M2e were seen in NP+M2-rAd immunized BALB/c but not C57BL/6 mice, and cross-reacted with pH1N1 M2e. The ca-immunized mice did not develop antibodies against M2e. Despite sequence differences between vaccine and challenge virus NP and M2e epitopes, extensive cross-reactivity of lung T cells with pH1N1 peptides was detected following immunization. Both ca and NP+M2-rAd immunization protected BALB/c and C57BL/6 mice against challenge with a mouse-adapted pH1N1 virus.Cross-protective vaccines such as NP+M2-rAd and ca virus are effective against pH1N1 challenge within 3 weeks of immunization. Protection was not dependent on recognition of the highly variable external viral proteins and could be achieved with a single vaccine dose. The rAd vaccine was superior to the ca vaccine by certain measures, justifying continued investigation of this experimental vaccine even though ca vaccine is already available. This study highlights the potential for cross-protective vaccines as a public health option early in an influenza pandemic.

Novel Role for Interleukin-17 in Enhancing Type 1 Helper T Cell Immunity in the Female Genital Tract following Mucosal Herpes Simplex Virus 2 Vaccination.

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Bagri, Puja; Anipindi, Varun C; Nguyen, Philip V; Vitali, Danielle; Stämpfli, Martin R; Kaushic, Charu

2017-12-01

It is well established that interferon gamma (IFN-γ) production by CD4 + T cells is critical for antiviral immunity against herpes simplex virus 2 (HSV-2) genital infection. However, the role of interleukin-17A (IL-17A) production by CD4 + T cells in HSV-2 antiviral immunity is yet to be elucidated. Here we demonstrate that IL-17A plays an important role in enhancing antiviral T helper type 1 (T h 1) responses in the female genital tract (FGT) and is essential for effective protection conferred by HSV-2 vaccination. While IL-17A did not play a critical role during primary genital HSV-2 infection, seen by lack of differences in susceptibility between IL-17A-deficient ( IL-17A -/- ) and wild-type (WT) C57BL/6 mice, it was critical for mediating antiviral responses after challenge/reexposure. Compared to WT mice, IL-17A -/- mice (i) infected intravaginally and reexposed or (ii) vaccinated intranasally and challenged intravaginally demonstrated poor outcomes. Following intravaginal HSV-2 reexposure or challenge, vaccinated IL-17A -/- mice had significantly higher mortality, greater disease severity, higher viral shedding, and higher levels of proinflammatory cytokines and chemokines in vaginal secretions. Furthermore, IL-17A -/- mice had impaired T h 1 cell responses after challenge/reexposure, with significantly lower proportions of vaginal IFN-γ + CD4 + T cells. The impaired T h 1 cell responses in IL-17A -/- mice coincided with smaller populations of IFN-γ + CD4 + tissue resident memory T (T RM ) cells in the genital tract postimmunization. Taken together, these findings describe a novel role for IL-17A in regulating antiviral IFN-γ + T h 1 cell immunity in the vaginal tract. This strategy could be exploited to enhance antiviral immunity following HSV-2 vaccination. IMPORTANCE T helper type 1 (T h 1) immunity, specifically interferon gamma (IFN-γ) production by CD4 + T cells, is critical for protection against genital herpesvirus (HSV-2) infection, and

The pathogenicity of thymidine kinase-deficient mutants of herpes simplex virus in mice.

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Field, H J; Wildy, P

1978-10-01

The pathogenicity for mice of two mutants of herpes simplex virus (type 1 and type 2), which fail to induce thymidine kinase, were compared with their respective parent strains. The mutants were much less virulent than the parents following either intracerebral or peripheral inoculation. The replication of the virus at the site of inoculation and its progression into the nervous system were studied. Following a very large inoculum in the ear, the type 1 mutant was found to establish a latent infection in the cervical dorsal root ganglia. Mice inoculated intracerebrally with small doses of the mutant viruses were solidly immune to challenge with lethal doses of the parent strain.

IL-1 signal affects both protection and pathogenesis of virus-induced chronic CNS demyelinating disease

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Kim Byung S

2012-09-01

Full Text Available Abstract Background Theiler’s virus infection induces chronic demyelinating disease in mice and has been investigated as an infectious model for multiple sclerosis (MS. IL-1 plays an important role in the pathogenesis of both the autoimmune disease model (EAE and this viral model for MS. However, IL-1 is known to play an important protective role against certain viral infections. Therefore, it is unclear whether IL-1-mediated signaling plays a protective or pathogenic role in the development of TMEV-induced demyelinating disease. Methods Female C57BL/6 mice and B6.129S7-Il1r1tm1Imx/J mice (IL-1R KO were infected with Theiler’s murine encephalomyelitis virus (1 x 106 PFU. Differences in the development of demyelinating disease and changes in the histopathology were compared. Viral persistence, cytokine production, and immune responses in the CNS of infected mice were analyzed using quantitative PCR, ELISA, and flow cytometry. Results Administration of IL-1β, thereby rending resistant B6 mice susceptible to TMEV-induced demyelinating disease, induced a high level of Th17 response. Interestingly, infection of TMEV into IL-1R-deficient resistant C57BL/6 (B6 mice also induced TMEV-induced demyelinating disease. High viral persistence was found in the late stage of viral infection in IL-1R-deficient mice, although there were few differences in the initial anti-viral immune responses and viral persistent levels between the WT B6 and IL-1R-deficiecent mice. The initial type I IFN responses and the expression of PDL-1 and Tim-3 were higher in the CNS of TMEV-infected IL-1R-deficient mice, leading to deficiencies in T cell function that permit viral persistence. Conclusions These results suggest that the presence of high IL-1 level exerts the pathogenic role by elevating pathogenic Th17 responses, whereas the lack of IL-1 signals promotes viral persistence in the spinal cord due to insufficient T cell activation by elevating the production of

Characterization of soluble glycoprotein D-mediated herpes simplex virus type 1 infection

International Nuclear Information System (INIS)

Tsvitov, Marianna; Frampton, Arthur R.; Shah, Waris A.; Wendell, Steven K.; Ozuer, Ali; Kapacee, Zoher; Goins, William F.; Cohen, Justus B.; Glorioso, Joseph C.

2007-01-01

Herpes simplex virus type 1 (HSV-1) entry into permissive cells involves attachment to cell-surface glycosaminoglycans (GAGs) and fusion of the virus envelope with the cell membrane triggered by the binding of glycoprotein D (gD) to cognate receptors. In this study, we characterized the observation that soluble forms of the gD ectodomain (sgD) can mediate entry of gD-deficient HSV-1. We examined the efficiency and receptor specificity of this activity and used sequential incubation protocols to determine the order and stability of the initial interactions required for entry. Surprisingly, virus binding to GAGs did not increase the efficiency of sgD-mediated entry and gD-deficient virus was capable of attaching to GAG-deficient cells in the absence of sgD. These observations suggested a novel binding interaction that may play a role in normal HSV infection

Serum-free microcarrier based production of replication deficient Influenza vaccine candidate virus lacking NS1 using Vero cells

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Yan Mylene L

2011-08-01

Full Text Available Abstract Background Influenza virus is a major health concern that has huge impacts on the human society, and vaccination remains as one of the most effective ways to mitigate this disease. Comparing the two types of commercially available Influenza vaccine, the live attenuated virus vaccine is more cross-reactive and easier to administer than the traditional inactivated vaccines. One promising live attenuated Influenza vaccine that has completed Phase I clinical trial is deltaFLU, a deletion mutant lacking the viral Nonstructural Protein 1 (NS1 gene. As a consequence of this gene deletion, this mutant virus can only propagate effectively in cells with a deficient interferon-mediated antiviral response. To demonstrate the manufacturability of this vaccine candidate, a batch bioreactor production process using adherent Vero cells on microcarriers in commercially available animal-component free, serum-free media is described. Results Five commercially available animal-component free, serum-free media (SFM were evaluated for growth of Vero cells in agitated Cytodex 1 spinner flask microcarrier cultures. EX-CELL Vero SFM achieved the highest cell concentration of 2.6 × 10^6 cells/ml, whereas other SFM achieved about 1.2 × 10^6 cells/ml. Time points for infection between the late exponential and stationary phases of cell growth had no significant effect in the final virus titres. A virus yield of 7.6 Log10 TCID50/ml was achieved using trypsin concentration of 10 μg/ml and MOI of 0.001. The Influenza vaccine production process was scaled up to a 3 liter controlled stirred tank bioreactor to achieve a cell density of 2.7 × 10^6 cells/ml and virus titre of 8.3 Log10 TCID50/ml. Finally, the bioreactor system was tested for the production of the corresponding wild type H1N1 Influenza virus, which is conventionally used in the production of inactivated vaccine. High virus titres of up to 10 Log10 TCID50/ml were achieved. Conclusions We describe for the

Sensitization with vaccinia virus encoding H5N1 hemagglutinin restores immune potential against H5N1 influenza virus.

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Yasui, Fumihiko; Itoh, Yasushi; Ikejiri, Ai; Kitabatake, Masahiro; Sakaguchi, Nobuo; Munekata, Keisuke; Shichinohe, Shintaro; Hayashi, Yukiko; Ishigaki, Hirohito; Nakayama, Misako; Sakoda, Yoshihiro; Kida, Hiroshi; Ogasawara, Kazumasa; Kohara, Michinori

2016-11-28

H5N1 highly pathogenic avian influenza (H5N1 HPAI) virus causes elevated mortality compared with seasonal influenza viruses like H1N1 pandemic influenza (H1N1 pdm) virus. We identified a mechanism associated with the severe symptoms seen with H5N1 HPAI virus infection. H5N1 HPAI virus infection induced a decrease of dendritic cell number in the splenic extrafollicular T-cell zone and impaired formation of the outer layers of B-cell follicles, resulting in insufficient levels of antibody production after infection. However, in animals vaccinated with a live recombinant vaccinia virus expressing the H5 hemagglutinin, infection with H5N1 HPAI virus induced parafollicular dendritic cell accumulation and efficient antibody production. These results indicate that a recombinant vaccinia encoding H5 hemagglutinin gene does not impair dendritic cell recruitment and can be a useful vaccine candidate.

Plasmid DNA initiates replication of yellow fever vaccine in vitro and elicits virus-specific immune response in mice.

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Tretyakova, Irina; Nickols, Brian; Hidajat, Rachmat; Jokinen, Jenny; Lukashevich, Igor S; Pushko, Peter

2014-11-01

Yellow fever (YF) causes an acute hemorrhagic fever disease in tropical Africa and Latin America. To develop a novel experimental YF vaccine, we applied iDNA infectious clone technology. The iDNA represents plasmid that encodes the full-length RNA genome of 17D vaccine downstream from a cytomegalovirus (CMV) promoter. The vaccine was designed to transcribe the full-length viral RNA and to launch 17D vaccine virus in vitro and in vivo. Transfection with 10 ng of iDNA plasmid was sufficient to start replication of vaccine virus in vitro. Safety of the parental 17D and iDNA-derived 17D viruses was confirmed in AG129 mice deficient in receptors for IFN-α/β/γ. Finally, direct vaccination of BALB/c mice with a single 20 μg dose of iDNA plasmid resulted in seroconversion and elicitation of virus-specific neutralizing antibodies in animals. We conclude that iDNA immunization approach combines characteristics of DNA and attenuated vaccines and represents a promising vaccination strategy for YF. Copyright © 2014 Elsevier Inc. All rights reserved.

Use of modified live feline panleukopenia virus vaccine to immunize dogs against canine parvovirus.

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Pollock, R V; Carmichael, L E

1983-02-01

Modified live feline panleukopenia virus (FPLV) vaccine protected dogs against canine parvovirus (CPV) infection. However, unlike the long-lived (greater than or equal to 20-month) immunity engendered by CPV infection, the response of dogs to living FPLV was variable. Doses of FPLV (snow leopard strain) in excess of 10(5.7) TCID50 were necessary for uniform immunization; smaller inocula resulted in decreased success rates. The duration of immunity, as measured by the persistence of hemagglutination-inhibiting antibody, was related to the magnitude of the initial response to vaccination; dogs with vigorous initial responses resisted oronasal CPV challenge exposure 6 months after vaccination, and hemagglutination-inhibiting antibodies persisted in such dogs for greater than 1 year. Limited replication of FPLV in dogs was demonstrated, but unlike CPV, the feline virus did not spread to contact dogs or cats. Adverse reactions were not associated with living FPLV vaccination, and FPLV did not interfere with simultaneous response to attenuated canine distemper virus.

The critical role of Notch ligand Delta-like 1 in the pathogenesis of influenza A virus (H1N1 infection.

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Toshihiro Ito

2011-11-01

Full Text Available Influenza A viral infections have been identified as the etiologic agents for historic pandemics, and contribute to the annual mortality associated with acute viral pneumonia. While both innate and acquired immunity are important in combating influenza virus infection, the mechanism connecting these arms of the immune system remains unknown. Recent data have indicated that the Notch system is an important bridge between antigen-presenting cells (APCs and T cell communication circuits and plays a central role in driving the immune system to overcome disease. In the present study, we examine the role of Notch signaling during influenza H1N1 virus infection, focusing on APCs. We demonstrate here that macrophages, but not dendritic cells (DCs, increased Notch ligand Delta-like 1 (Dll1 expression following influenza virus challenge. Dll1 expression on macrophages was dependent on retinoic acid-inducible gene-I (RIG-I induced type-I IFN pathway, and not on the TLR3-TRIF pathway. We also found that IFNα-Receptor knockout mice failed to induce Dll1 expression on lung macrophages and had enhanced mortality during influenza virus infection. Our results further showed that specific neutralization of Dll1 during influenza virus challenge induced higher mortality, impaired viral clearance, and decreased levels of IFN-γ. In addition, we blocked Notch signaling by using γ-secretase inhibitor (GSI, a Notch signaling inhibitor. Intranasal administration of GSI during influenza infection also led to higher mortality, and higher virus load with excessive inflammation and an impaired production of IFN-γ in lungs. Moreover, Dll1 expression on macrophages specifically regulates IFN-γ levels from CD4(+and CD8(+T cells, which are important for anti-viral immunity. Together, the results of this study show that Dll1 positively influences the development of anti-viral immunity, and may provide mechanistic approaches for modifying and controlling the immune response

Can VHS virus bypass the protective immunity induced by DNA vaccination in rainbow trout?

DEFF Research Database (Denmark)

Sepúlveda, Dagoberto; Lorenzen, Niels

2016-01-01

DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability...... and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV), an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly...... pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach), and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach). For the in vitro approach, the virus collected from the last passage (passaged virus) was as sensitive as the parental virus...

Increase of cells expressing PD-L1 in bovine leukemia virus infection and enhancement of anti-viral immune responses in vitro via PD-L1 blockade

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Ikebuchi Ryoyo

2011-09-01

Full Text Available Abstract The inhibitory receptor programmed death-1 (PD-1 and its ligand, programmed death-ligand 1 (PD-L1 are involved in immune evasion mechanisms for several pathogens causing chronic infections. Blockade of the PD-1/PD-L1 pathway restores anti-virus immune responses, with concomitant reduction in viral load. In a previous report, we showed that, in bovine leukemia virus (BLV infection, the expression of bovine PD-1 is closely associated with disease progression. However, the functions of bovine PD-L1 are still unknown. To investigate the role of PD-L1 in BLV infection, we identified the bovine PD-L1 gene, and examined PD-L1 expression in BLV-infected cattle in comparison with uninfected cattle. The deduced amino acid sequence of bovine PD-L1 shows high homology to the human and mouse PD-L1. The proportion of PD-L1 positive cells, especially among B cells, was upregulated in cattle with the late stage of the disease compared to cattle at the aleukemic infection stage or uninfected cattle. The proportion of PD-L1 positive cells correlated positively with prediction markers for the progression of the disease such as leukocyte number, virus load and virus titer whilst on the contrary, it inversely correlated with the degree of interferon-gamma expression. Blockade of the PD-1/PD-L1 pathway in vitro by PD-L1-specific antibody upregulated the production of interleukin-2 and interferon-gamma, and correspondingly, downregulated the BLV provirus load and the proportion of BLV-gp51 expressing cells. These data suggest that PD-L1 induces immunoinhibition in disease progressed cattle during chronic BLV infection. Therefore, PD-L1 would be a potential target for developing immunotherapies against BLV infection.

Expression Dynamics of Innate Immunity in Influenza Virus-Infected Swine

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Massimo Amadori

2017-04-01

Full Text Available The current circulating swine influenza virus (IV subtypes in Europe (H1N1, H1N2, and H3N2 are associated with clinical outbreaks of disease. However, we showed that pigs could be susceptible to other IV strains that are able to cross the species barrier. In this work, we extended our investigations into whether different IV strains able to cross the species barrier might give rise to different innate immune responses that could be associated with pathological lesions. For this purpose, we used the same samples collected in a previous study of ours, in which healthy pigs had been infected with a H3N2 Swine IV and four different H3N8 IV strains circulating in different animal species. Pigs had been clinically inspected and four subjects/group were sacrificed at 3, 6, and 21 days post infection. In the present study, all groups but mock exhibited antibody responses to IV nucleoprotein protein. Pulmonary lesions and high-titered viral replication were observed in pigs infected with the swine-adapted virus. Interestingly, pigs infected with avian and seal H3N8 strains also showed moderate lesions and viral replication, whereas equine and canine IVs did not cause overt pathological signs, and replication was barely detectable. Swine IV infection induced interferon (IFN-alpha and interleukin-6 responses in bronchoalveolar fluids (BALF at day 3 post infection, as opposed to the other non-swine-adapted virus strains. However, IFN-alpha responses to the swine-adapted virus were not associated with an increase of the local, constitutive expression of IFN-alpha genes. Remarkably, the Equine strain gave rise to a Serum Amyloid A response in BALF despite little if any replication. Each virus strain could be associated with expression of cytokine genes and/or proteins after infection. These responses were observed well beyond the period of virus replication, suggesting a prolonged homeostatic imbalance of the innate immune system.

UBXN1 Interferes with Rig-I-like Receptor-Mediated Antiviral Immune Response by Targeting MAVS

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Penghua Wang

2013-04-01

Full Text Available RNA viruses are sensed by RIG-I-like receptors (RLRs, which signal through a mitochondria-associated adaptor molecule, MAVS, resulting in systemic antiviral immune responses. Although RLR signaling is essential for limiting RNA virus replication, it must be stringently controlled to prevent damage from inflammation. We demonstrate here that among all tested UBX-domain-containing protein family members, UBXN1 exhibits the strongest inhibitory effect on RNA-virus-induced type I interferon response. UBXN1 potently inhibits RLR- and MAVS-induced, but not TLR3-, TLR4-, or DNA-virus-induced innate immune responses. Depletion of UBXN1 enhances virus-induced innate immune responses, including those resulting from RNA viruses such as vesicular stomatitis, Sendai, West Nile, and dengue virus infection, repressing viral replication. Following viral infection, UBXN1 is induced, binds to MAVS, interferes with intracellular MAVS oligomerization, and disrupts the MAVS/TRAF3/TRAF6 signalosome. These findings underscore a critical role of UBXN1 in the modulation of a major antiviral signaling pathway.

Mucosal immunity induced by adenovirus-based H5N1 HPAI vaccine confers protection against a lethal H5N2 avian influenza virus challenge

International Nuclear Information System (INIS)

Park, Ki Seok; Lee, Jiyeung; Ahn, So Shin; Byun, Young-Ho; Seong, Baik Lin; Baek, Yun Hee; Song, Min-Suk; Choi, Young Ki; Na, Yun Jeong; Hwang, Inhwan; Sung, Young Chul; Lee, Chang Geun

2009-01-01

Development of effective vaccines against highly pathogenic avian influenza (HPAI) H5N1 viruses is a global public health priority. Considering the difficulty in predicting HPAI H5N1 pandemic strains, one strategy used in their design includes the development of formulations with the capacity of eliciting broad cross-protective immunity against multiple viral antigens. To this end we constructed a replication-defective recombinant adenovirus-based avian influenza virus vaccine (rAdv-AI) expressing the codon-optimized M2eX-HA-hCD40L and the M1-M2 fusion genes from HPAI H5N1 human isolate. Although there were no significant differences in the systemic immune responses observed between the intramuscular prime-intramuscular boost regimen (IM/IM) and the intranasal prime-intramuscular boost regimen (IN/IM), IN/IM induced more potent CD8 + T cell and antibody responses at mucosal sites than the IM/IM vaccination, resulting in more effective protection against lethal H5N2 avian influenza (AI) virus challenge. These findings suggest that the strategies used to induce multi-antigen-targeted mucosal immunity, such as IN/IM delivery of rAdv-AI, may be a promising approach for developing broad protective vaccines that may be more effective against the new HPAI pandemic strains.

Cold-Adapted Influenza and Recombinant Adenovirus Vaccines Induce Cross-Protective Immunity against pH1N1 Challenge in Mice

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Soboleski, Mark R.; Gabbard, Jon D.; Price, Graeme E.; Misplon, Julia A.; Lo, Chia-Yun; Perez, Daniel R.; Ye, Jianqiang; Tompkins, S. Mark; Epstein, Suzanne L.

2011-01-01

Background The rapid spread of the 2009 H1N1 pandemic influenza virus (pH1N1) highlighted problems associated with relying on strain-matched vaccines. A lengthy process of strain identification, manufacture, and testing is required for current strain-matched vaccines and delays vaccine availability. Vaccines inducing immunity to conserved viral proteins could be manufactured and tested in advance and provide cross-protection against novel influenza viruses until strain-matched vaccines became available. Here we test two prototype vaccines for cross-protection against the recent pandemic virus. Methodology/Principal Findings BALB/c and C57BL/6 mice were intranasally immunized with a single dose of cold-adapted (ca) influenza viruses from 1977 or recombinant adenoviruses (rAd) expressing 1934 nucleoprotein (NP) and consensus matrix 2 (M2) (NP+M2-rAd). Antibodies against the M2 ectodomain (M2e) were seen in NP+M2-rAd immunized BALB/c but not C57BL/6 mice, and cross-reacted with pH1N1 M2e. The ca-immunized mice did not develop antibodies against M2e. Despite sequence differences between vaccine and challenge virus NP and M2e epitopes, extensive cross-reactivity of lung T cells with pH1N1 peptides was detected following immunization. Both ca and NP+M2-rAd immunization protected BALB/c and C57BL/6 mice against challenge with a mouse-adapted pH1N1 virus. Conclusion/Significance Cross-protective vaccines such as NP+M2-rAd and ca virus are effective against pH1N1 challenge within 3 weeks of immunization. Protection was not dependent on recognition of the highly variable external viral proteins and could be achieved with a single vaccine dose. The rAd vaccine was superior to the ca vaccine by certain measures, justifying continued investigation of this experimental vaccine even though ca vaccine is already available. This study highlights the potential for cross-protective vaccines as a public health option early in an influenza pandemic. PMID:21789196

Humans and ferrets with prior H1N1 influenza virus infections do not exhibit evidence of original antigenic sin after infection or vaccination with the 2009 pandemic H1N1 influenza virus.

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O'Donnell, Christopher D; Wright, Amber; Vogel, Leatrice; Boonnak, Kobporn; Treanor, John J; Subbarao, Kanta

2014-05-01

The hypothesis of original antigenic sin (OAS) states that the imprint established by an individual's first influenza virus infection governs the antibody response thereafter. Subsequent influenza virus infection results in an antibody response against the original infecting virus and an impaired immune response against the newer influenza virus. The purpose of our study was to seek evidence of OAS after infection or vaccination with the 2009 pandemic H1N1 (2009 pH1N1) virus in ferrets and humans previously infected with H1N1 viruses with various antigenic distances from the 2009 pH1N1 virus, including viruses from 1935 through 1999. In ferrets, seasonal H1N1 priming did not diminish the antibody response to infection or vaccination with the 2009 pH1N1 virus, nor did it diminish the T-cell response, indicating the absence of OAS in seasonal H1N1 virus-primed ferrets. Analysis of paired samples of human serum taken before and after vaccination with a monovalent inactivated 2009 pH1N1 vaccine showed a significantly greater-fold rise in the titer of antibody against the 2009 pH1N1 virus than against H1N1 viruses that circulated during the childhood of each subject. Thus, prior experience with H1N1 viruses did not result in an impairment of the antibody response against the 2009 pH1N1 vaccine. Our data from ferrets and humans suggest that prior exposure to H1N1 viruses did not impair the immune response against the 2009 pH1N1 virus.

Ebola Virus Altered Innate and Adaptive Immune Response Signalling Pathways: Implications for Novel Therapeutic Approaches.

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Kumar, Anoop

2016-01-01

Ebola virus (EBOV) arise attention for their impressive lethality by the poor immune response and high inflammatory reaction in the patients. It causes a severe hemorrhagic fever with case fatality rates of up to 90%. The mechanism underlying this lethal outcome is poorly understood. In 2014, a major outbreak of Ebola virus spread amongst several African countries, including Leone, Sierra, and Guinea. Although infections only occur frequently in Central Africa, but the virus has the potential to spread globally. Presently, there is no vaccine or treatment is available to counteract Ebola virus infections due to poor understanding of its interaction with the immune system. Accumulating evidence indicates that the virus actively alters both innate and adaptive immune responses and triggers harmful inflammatory responses. In the literature, some reports have shown that alteration of immune signaling pathways could be due to the ability of EBOV to interfere with dendritic cells (DCs), which link innate and adaptive immune responses. On the other hand, some reports have demonstrated that EBOV, VP35 proteins act as interferon antagonists. So, how the Ebola virus altered the innate and adaptive immune response signaling pathways is still an open question for the researcher to be explored. Thus, in this review, I try to summarize the mechanisms of the alteration of innate and adaptive immune response signaling pathways by Ebola virus which will be helpful for designing effective drugs or vaccines against this lethal infection. Further, potential targets, current treatment and novel therapeutic approaches have also been discussed.

The production of antibody by invading B cells is required for the clearance of rabies virus from the central nervous system.

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D Craig Hooper

2009-10-01

Full Text Available The pathogenesis of rabies is associated with the inability to deliver immune effectors across the blood-brain barrier and to clear virulent rabies virus from CNS tissues. However, the mechanisms that facilitate immune effector entry into CNS tissues are induced by infection with attenuated rabies virus.Infection of normal mice with attenuated rabies virus but not immunization with killed virus can promote the clearance of pathogenic rabies virus from the CNS. T cell activity in B cell-deficient mice can control the replication of attenuated virus in the CNS, but viral mRNA persists. Low levels of passively administered rabies virus-neutralizing antibody reach infected cells in the cerebellum of B cell-deficient mice but are not sufficient to mediate virus clearance. Production of rabies virus-specific antibody by B cells invading CNS tissues is required for this process, and a substantial proportion of the B cells that accumulate in the CNS of mice infected with attenuated rabies virus produce virus-specific antibodies.The mechanisms required for immune effectors to enter rabies virus-infected tissues are induced by infection with attenuated rabies virus but not by infection with pathogenic rabies viruses or immunization with killed virus. T cell activities can inhibit rabies virus replication, but the production of rabies virus-specific antibodies by infiltrating B cells, as opposed to the leakage of circulating antibody across the BBB, is critical to elimination of the virus. These findings suggest that a pathogenic rabies virus infection may be treatable after the virus has reached the CNS tissues, providing that the appropriate immune effectors can be targeted to the infected tissues.

Canine Distemper Virus (CDV) immune-stimulating complexes (iscoms), but not measles virus iscoms, protect dogs against CDV infection.

NARCIS (Netherlands)

P. de Vries (Petra); F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Albert)

1988-01-01

textabstractThe potential of immune-stimulating complexes (iscoms), a novel form of antigenic presentation, for the induction of protective immunity against morbillivirus infection was shown by immunizing dogs with canine distemper virus (CDV) iscoms, which contained the fusion (F) protein and a

Modulation of Host Immunity by Human Respiratory Syncytial Virus Virulence Factors: A Synergic Inhibition of Both Innate and Adaptive Immunity

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Gisela Canedo-Marroquín

2017-08-01

Full Text Available The Human Respiratory Syncytial Virus (hRSV is a major cause of acute lower respiratory tract infections (ARTIs and high rates of hospitalizations in children and in the elderly worldwide. Symptoms of hRSV infection include bronchiolitis and pneumonia. The lung pathology observed during hRSV infection is due in part to an exacerbated host immune response, characterized by immune cell infiltration to the lungs. HRSV is an enveloped virus, a member of the Pneumoviridae family, with a non-segmented genome and negative polarity-single RNA that contains 10 genes encoding for 11 proteins. These include the Fusion protein (F, the Glycoprotein (G, and the Small Hydrophobic (SH protein, which are located on the virus surface. In addition, the Nucleoprotein (N, Phosphoprotein (P large polymerase protein (L part of the RNA-dependent RNA polymerase complex, the M2-1 protein as a transcription elongation factor, the M2-2 protein as a regulator of viral transcription and (M protein all of which locate inside the virion. Apart from the structural proteins, the hRSV genome encodes for the non-structural 1 and 2 proteins (NS1 and NS2. HRSV has developed different strategies to evade the host immunity by means of the function of some of these proteins that work as virulence factors to improve the infection in the lung tissue. Also, hRSV NS-1 and NS-2 proteins have been shown to inhibit the activation of the type I interferon response. Furthermore, the hRSV nucleoprotein has been shown to inhibit the immunological synapsis between the dendritic cells and T cells during infection, resulting in an inefficient T cell activation. Here, we discuss the hRSV virulence factors and the host immunological features raised during infection with this virus.

Establishing a small animal model for evaluating protective immunity against mumps virus.

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Adrian Pickar

Full Text Available Although mumps vaccines have been used for several decades, protective immune correlates have not been defined. Recently, mumps outbreaks have occurred in vaccinated populations. To better understand the causes of the outbreaks and to develop means to control outbreaks in mumps vaccine immunized populations, defining protective immune correlates will be critical. Unfortunately, no small animal model for assessing mumps immunity exists. In this study, we evaluated use of type I interferon (IFN alpha/beta receptor knockout mice (IFN-α/βR-/- for such a model. We found these mice to be susceptible to mumps virus administered intranasally and intracranially. Passive transfer of purified IgG from immunized mice protected naïve mice from mumps virus infection, confirming the role of antibody in protection and demonstrating the potential for this model to evaluate mumps immunity.

Buying Time—The Immune System Determinants of the Incubation Period to Respiratory Viruses

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Thomas M. Moran

2010-11-01

Full Text Available Respiratory viruses cause disease in humans characterized by an abrupt onset of symptoms. Studies in humans and animal models have shown that symptoms are not immediate and appear days or even weeks after infection. Since the initial symptoms are a manifestation of virus recognition by elements of the innate immune response, early virus replication must go largely undetected. The interval between infection and the emergence of symptoms is called the incubation period and is widely used as a clinical score. While incubation periods have been described for many virus infections the underlying mechanism for this asymptomatic phase has not been comprehensively documented. Here we review studies of the interaction between human pathogenic respiratory RNA viruses and the host with a particular emphasis on the mechanisms used by viruses to inhibit immunity. We discuss the concept of the “stealth phase”, defined as the time between infection and the earliest detectable inflammatory response. We propose that the “stealth phase” phenomenon is primarily responsible for the suppression of symptoms during the incubation period and results from viral antagonism that inhibits major pathways of the innate immune system allowing an extended time of unhindered virus replication.

Infection-derived lipids elicit a novel immune deficiency circuitry in arthropods

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The insect Immune Deficiency (IMD) pathway resembles the tumor necrosis factor receptor network in mammals and senses diaminopimelic-type peptidoglycans present in Gram-negative bacteria. Whether unidentified chemical moieties elicit the IMD signaling cascade remains unknown. Here, we disclose thoug...

Use of a novel chimeric mouse model with a functionally active human immune system to study human immunodeficiency virus type 1 infection

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An, Dong Sung; Poon, Betty; Tsong Fang, Raphael Ho; Weijer, Kees; Blom, Bianca; Spits, Hergen; Chen, Irvin S. Y.; Uittenbogaart, Christel H.

2007-01-01

The goal of this study was to develop a small-animal model to study human immunodeficiency virus type 1 (HIV-1) pathogenesis in blood and primary and secondary lymphoid organs. Rag2(-/-)gamma(c)(-/-) mice that are neonatally injected with human CD34(+) cells develop a functional human immune system

Humoral and cell-mediated immune responses in DNA immunized mink challenged with wild-type canine distemper virus

DEFF Research Database (Denmark)

Nielsen, Line; Søgaard, Mette; Karlskov-Mortensen, Peter

2009-01-01

The aim of the study was to investigate the different phases of the immune response after DNA immunization with the hemagglutinin and nucleoprotein genes from canine distemper virus (CDV). Although attenuated live CDV vaccines have effectively reduced the incidence of disease, canine distemper...

E3L and F1L Gene Functions Modulate the Protective Capacity of Modified Vaccinia Virus Ankara Immunization in Murine Model of Human Smallpox

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Asisa Volz

2018-01-01

Full Text Available The highly attenuated Modified Vaccinia virus Ankara (MVA lacks most of the known vaccinia virus (VACV virulence and immune evasion genes. Today MVA can serve as a safety-tested next-generation smallpox vaccine. Yet, we still need to learn about regulatory gene functions preserved in the MVA genome, such as the apoptosis inhibitor genes F1L and E3L. Here, we tested MVA vaccine preparations on the basis of the deletion mutant viruses MVA-ΔF1L and MVA-ΔE3L for efficacy against ectromelia virus (ECTV challenge infections in mice. In non-permissive human tissue culture the MVA deletion mutant viruses produced reduced levels of the VACV envelope antigen B5. Upon mousepox challenge at three weeks after vaccination, MVA-ΔF1L and MVA-ΔE3L exhibited reduced protective capacity in comparison to wildtype MVA. Surprisingly, however, all vaccines proved equally protective against a lethal ECTV infection at two days after vaccination. Accordingly, the deletion mutant MVA vaccines induced high levels of virus-specific CD8+ T cells previously shown to be essential for rapidly protective MVA vaccination. These results suggest that inactivation of the anti-apoptotic genes F1L or E3L modulates the protective capacity of MVA vaccination most likely through the induction of distinct orthopoxvirus specific immunity in the absence of these viral regulatory proteins.

In Vivo Imaging of Influenza Virus Infection in Immunized Mice

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Rita Czakó

2017-05-01

Full Text Available Immunization is the cornerstone of seasonal influenza control and represents an important component of pandemic preparedness strategies. Using a bioluminescent reporter virus, we demonstrate the application of noninvasive in vivo imaging system (IVIS technology to evaluate the preclinical efficacy of candidate vaccines and immunotherapy in a mouse model of influenza. Sequential imaging revealed distinct spatiotemporal kinetics of bioluminescence in groups of mice passively or actively immunized by various strategies that accelerated the clearance of the challenge virus at different rates and by distinct mechanisms. Imaging findings were consistent with conclusions derived from virus titers in the lungs and, notably, were more informative than conventional efficacy endpoints in some cases. Our findings demonstrate the reliability of IVIS as a qualitative approach to support preclinical evaluation of candidate medical countermeasures for influenza in mice.

Stability of a general delayed virus dynamics model with humoral immunity and cellular infection

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Elaiw, A. M.; Raezah, A. A.; Alofi, A. S.

2017-06-01

In this paper, we investigate the dynamical behavior of a general nonlinear model for virus dynamics with virus-target and infected-target incidences. The model incorporates humoral immune response and distributed time delays. The model is a four dimensional system of delay differential equations where the production and removal rates of the virus and cells are given by general nonlinear functions. We derive the basic reproduction parameter R˜0 G and the humoral immune response activation number R˜1 G and establish a set of conditions on the general functions which are sufficient to determine the global dynamics of the models. We use suitable Lyapunov functionals and apply LaSalle's invariance principle to prove the global asymptotic stability of the all equilibria of the model. We confirm the theoretical results by numerical simulations.

Ebola haemorrhagic fever virus: pathogenesis, immune responses, potential prevention.

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Marcinkiewicz, Janusz; Bryniarski, Krzysztof; Nazimek, Katarzyna

2014-01-01

Ebola zoonotic RNA filovirus represents human most virulent and lethal pathogens, which induces acute hemorrhagic fever and death within few days in a range of 60-90% of symptomatic individuals. Last outbreak in 2014 in West Africa caused panic that Ebola epidemic can be spread to other continents. Number of deaths in late December reached almost 8,000 individuals out of more than 20,000 symptomatic patients. It seems that only a coordinated international response could counteract the further spread of Ebola. Major innate immunity mechanisms against Ebola are associated with the production of interferons, that are inhibited by viral proteins. Activation of host NK cells was recognized as a leading immune function responsible for recovery of infected people. Uncontrolled cell infection by Ebola leads to an impairment of immunity with cytokine storm, coagulopathy, systemic bleeding, multi-organ failure and death. Tested prevention strategies to induce antiviral immunity include: i. recombinant virus formulations (vaccines); ii. cocktail of monoclonal antibodies (serotherapy); iii. alternative RNA-interference-based antiviral methods. Maintaining the highest standards of aseptic and antiseptic precautions is equally important. Present brief review summarizes a current knowledge concerning pathogenesis of Ebola hemorrhagic disease and the virus interaction with the immune system and discusses recent advances in prevention of Ebola infection by vaccination and serotherapy.

Differences in pathogenicity, response to vaccination, and innate immune responses in different types of ducks infected with a virulent H5N1 highly pathogenic avian influenza virus from Vietnam.

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Cagle, Caran; Wasilenko, Jamie; Adams, Sean C; Cardona, Carol J; To, Thanh Long; Nguyen, Tung; Spackman, Erica; Suarez, David L; Smith, Diane; Shepherd, Eric; Roth, Jason; Pantin-Jackwood, Mary J

2012-09-01

In a previous study, we found clear differences in pathogenicity and response to vaccination against H5N1 highly pathogenic avian influenza (HPAI; HA dade 2.3.4) between Pekin (Anas platyrhynchos var. domestica) and Muscovy (Cairina moschata) ducks vaccinated using a commercial inactivated vaccine (Re-1). The objective of the present study was to further investigate the pathogenicity of H5N1 HPAI viruses in different species of ducks by examining clinical signs and innate immune responses to infection with a different strain of H5N1 HPAI virus (HA clade 1) in two domestic ducks, Pekin and Muscovy, and one wild-type duck, mallard (Anas platyrhynchos). Protection conferred by vaccination using the Re-1 vaccine against infection with this virus was also compared between Pekin and Muscovy ducks. Differences in pathogenicity were observed among the virus-infected ducks, as the Muscovy ducks died 2 days earlier than did the Pekin and mallard ducks, and they presented more-severe neurologic signs. Conversely, the Pekin and mallard ducks had significantly higher body temperatures at 2 days postinfection (dpi) than did the Muscovy ducks, indicating possible differences in innate immune responses. However, similar expression of innate immune-related genes was found in the spleens of virus-infected ducks at this time point. In all three duck species, there was up-regulation of IFN-alpha, IFN-gamma, IL-6, CCL19, RIG-I, and MHC class I and down-regulation of MHC class II, but variable expression of IL-18 and TLR7. As in our previous study, vaccinated Muscovy ducks showed less protection against virus infection than did Pekin ducks, as evidenced by the higher mortality and higher number of Muscovy ducks shedding virus when compared to Pekin ducks. In conclusion, infection with an H5N1 HPAI virus produced a systemic infection with high mortality in all three duck species; however, the disease was more severe in Muscovy ducks, which also had a poor response to vaccination. The

Can VHS Virus Bypass the Protective Immunity Induced by DNA Vaccination in Rainbow Trout?

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Dagoberto Sepúlveda

Full Text Available DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV, an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach, and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach. For the in vitro approach, the virus collected from the last passage (passaged virus was as sensitive as the parental virus to serum neutralization, suggesting that the passaging did not promote the selection of virus populations able to bypass the neutralization by serum antibodies. Also, in the in vivo approach, where virus was passaged several times in vaccinated fish, no increased virulence nor increased persistence in vaccinated fish was observed in comparison with the parental virus. However, some of the vaccinated fish did get infected and could transmit the infection to naïve cohabitant fish. The results demonstrated that the DNA vaccine induced a robust protection, but also that the immunity was non-sterile. It is consequently important not to consider vaccinated fish as virus free in veterinary terms.

Impact of CD1d deficiency on metabolism.

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Maya E Kotas

Full Text Available Invariant natural killer T cells (iNKTs are innate-like T cells that are highly concentrated in the liver and recognize lipids presented on the MHC-like molecule CD1d. Although capable of a myriad of responses, few essential functions have been described for iNKTs. Among the many cell types of the immune system implicated in metabolic control and disease, iNKTs seem ideally poised for such a role, yet little has been done to elucidate such a possible function. We hypothesized that lipid presentation by CD1d could report on metabolic status and engage iNKTs to regulate cellular lipid content through their various effector mechanisms. To test this hypothesis, we examined CD1d deficient mice in a variety of metabolically stressed paradigms including high fat feeding, choline-deficient feeding, fasting, and acute inflammation. CD1d deficiency led to a mild exacerbation of steatosis during high fat or choline-deficient feeding, accompanied by impaired hepatic glucose tolerance. Surprisingly, however, this phenotype was not observed in Jα18⁻/⁻ mice, which are deficient in iNKTs but express CD1d. Thus, CD1d appears to modulate some metabolic functions through an iNKT-independent mechanism.

Type I J-domain NbMIP1 proteins are required for both Tobacco mosaic virus infection and plant innate immunity.

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Yumei Du

Full Text Available Tm-2² is a coiled coil-nucleotide binding-leucine rich repeat resistance protein that confers durable extreme resistance against Tomato mosaic virus (ToMV and Tobacco mosaic virus (TMV by recognizing the viral movement protein (MP. Here we report that the Nicotiana benthamiana J-domain MIP1 proteins (NbMIP1s associate with tobamovirus MP, Tm-2² and SGT1. Silencing of NbMIP1s reduced TMV movement and compromised Tm-2²-mediated resistance against TMV and ToMV. Furthermore, silencing of NbMIP1s reduced the steady-state protein levels of ToMV MP and Tm-2². Moreover, NbMIP1s are required for plant resistance induced by other R genes and the nonhost pathogen Pseudomonas syringae pv. tomato (Pst DC3000. In addition, we found that SGT1 associates with Tm-2² and is required for Tm-2²-mediated resistance against TMV. These results suggest that NbMIP1s function as co-chaperones during virus infection and plant immunity.

Chimeric plant virus particles administered nasally or orally induce systemic and mucosal immune responses in mice

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Brennan, F.R.; Bellaby, T.; Helliwell, S.M.

1999-01-01

The humoral immune responses to the D2 peptide of fibronectin-binding protein B (FnBP) of Staphylococcus aureus, expressed on the plant virus cowpea mosaic virus (CPMV), were evaluated after mucosal delivery to mice. Intranasal immunization of these chimeric virus particles (CVPs), either alone...

Immunization of Pigs by DNA Prime and Recombinant Vaccinia Virus Boost To Identify and Rank African Swine Fever Virus Immunogenic and Protective Proteins.

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Jancovich, James K; Chapman, Dave; Hansen, Debra T; Robida, Mark D; Loskutov, Andrey; Craciunescu, Felicia; Borovkov, Alex; Kibler, Karen; Goatley, Lynnette; King, Katherine; Netherton, Christopher L; Taylor, Geraldine; Jacobs, Bertram; Sykes, Kathryn; Dixon, Linda K

2018-04-15

African swine fever virus (ASFV) causes an acute hemorrhagic fever in domestic pigs, with high socioeconomic impact. No vaccine is available, limiting options for control. Although live attenuated ASFV can induce up to 100% protection against lethal challenge, little is known of the antigens which induce this protective response. To identify additional ASFV immunogenic and potentially protective antigens, we cloned 47 viral genes in individual plasmids for gene vaccination and in recombinant vaccinia viruses. These antigens were selected to include proteins with different functions and timing of expression. Pools of up to 22 antigens were delivered by DNA prime and recombinant vaccinia virus boost to groups of pigs. Responses of immune lymphocytes from pigs to individual recombinant proteins and to ASFV were measured by interferon gamma enzyme-linked immunosorbent spot (ELISpot) assays to identify a subset of the antigens that consistently induced the highest responses. All 47 antigens were then delivered to pigs by DNA prime and recombinant vaccinia virus boost, and pigs were challenged with a lethal dose of ASFV isolate Georgia 2007/1. Although pigs developed clinical and pathological signs consistent with acute ASFV, viral genome levels were significantly reduced in blood and several lymph tissues in those pigs immunized with vectors expressing ASFV antigens compared with the levels in control pigs. IMPORTANCE The lack of a vaccine limits the options to control African swine fever. Advances have been made in the development of genetically modified live attenuated ASFV that can induce protection against challenge. However, there may be safety issues relating to the use of these in the field. There is little information about ASFV antigens that can induce a protective immune response against challenge. We carried out a large screen of 30% of ASFV antigens by delivering individual genes in different pools to pigs by DNA immunization prime and recombinant vaccinia

Innate immune responses against foot-and-mouth disease virus: current understanding and future directions.

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Summerfield, Artur; Guzylack-Piriou, Laurence; Harwood, Lisa; McCullough, Kenneth C

2009-03-15

Foot-and-mouth disease (FMD) represents one of the most economically important diseases of farm animals. The basis for the threat caused by this virus is the high speed of replication, short incubation time, high contagiousness, and high mutation rate resulting in constant antigenic changes. Thus, although protective immune responses against FMD virus (FMDV) can be efficacious, the rapidity of virus replication and spread can outpace immune defence development and overrun the immune system. FMDV can also evade innate immune responses through its ability to shut down cellular protein synthesis, including IFN type I, in susceptible epithelial cells. This is important for virus evolution, as FMDV is quite sensitive to the action of IFN. Despite this, innate immune responses are probably induced in vivo, although detailed studies on this subject are lacking. Accordingly, this interaction of FMDV with cells of the innate immune system is of particular interest. Dendritic cells (DC) can be infected by FMDV and support viral RNA replication, and viral protein synthesis but the latter is inefficient or abortive, leading most often to incomplete replication and progeny virus release. As a result DC can be activated, and particularly in the case of plasmacytoid DC (pDC), this is manifest in terms of IFN-alpha release. Our current state of knowledge on innate immune responses induced by FMDV is still only at a relatively early stage of understanding. As we progress, the investigations in this area will help to improve the design of current vaccines and the development of novel control strategies against FMD.

Evasion of antiviral innate immunity by Theiler's virus L* protein through direct inhibition of RNase L.

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Frédéric Sorgeloos

Full Text Available Theiler's virus is a neurotropic picornavirus responsible for chronic infections of the central nervous system. The establishment of a persistent infection and the subsequent demyelinating disease triggered by the virus depend on the expression of L*, a viral accessory protein encoded by an alternative open reading frame of the virus. We discovered that L* potently inhibits the interferon-inducible OAS/RNase L pathway. The antagonism of RNase L by L* was particularly prominent in macrophages where baseline oligoadenylate synthetase (OAS and RNase L expression levels are elevated, but was detectable in fibroblasts after IFN pretreatment. L* mutations significantly affected Theiler's virus replication in primary macrophages derived from wild-type but not from RNase L-deficient mice. L* counteracted the OAS/RNase L pathway through direct interaction with the ankyrin domain of RNase L, resulting in the inhibition of this enzyme. Interestingly, RNase L inhibition was species-specific as Theiler's virus L* protein blocked murine RNase L but not human RNase L or RNase L of other mammals or birds. Direct RNase L inhibition by L* and species specificity were confirmed in an in vitro assay performed with purified proteins. These results demonstrate a novel viral mechanism to elude the antiviral OAS/RNase L pathway. By targeting the effector enzyme of this antiviral pathway, L* potently inhibits RNase L, underscoring the importance of this enzyme in innate immunity against Theiler's virus.

Prolonged protection against Intranasal challenge with influenza virus following systemic immunization or combinations of mucosal and systemic immunizations with a heat-labile toxin mutant.

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Zhou, Fengmin; Goodsell, Amanda; Uematsu, Yasushi; Vajdy, Michael

2009-04-01

Seasonal influenza virus infections cause considerable morbidity and mortality in the world, and there is a serious threat of a pandemic influenza with the potential to cause millions of deaths. Therefore, practical influenza vaccines and vaccination strategies that can confer protection against intranasal infection with influenza viruses are needed. In this study, we demonstrate that using LTK63, a nontoxic mutant of the heat-labile toxin from Escherichia coli, as an adjuvant for both mucosal and systemic immunizations, systemic (intramuscular) immunization or combinations of mucosal (intranasal) and intramuscular immunizations protected mice against intranasal challenge with a lethal dose of live influenza virus at 3.5 months after the second immunization.

Characterization of host immune responses in Ebola virus infections.

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Wong, Gary; Kobinger, Gary P; Qiu, Xiangguo

2014-06-01

Ebola causes highly lethal hemorrhagic fever in humans with no licensed countermeasures. Its virulence can be attributed to several immunoevasion mechanisms: an early inhibition of innate immunity started by the downregulation of type I interferon, epitope masking and subversion of the adaptive humoural immunity by secreting a truncated form of the viral glycoprotein. Deficiencies in specific and non-specific antiviral responses result in unrestricted viral replication and dissemination in the host, causing death typically within 10 days after the appearance of symptoms. This review summarizes the host immune response to Ebola infection, and highlights the short- and long-term immune responses crucial for protection, which holds implications for the design of future vaccines and therapeutics.

Flaviviridae virus nonstructural proteins 5 and 5A mediate viral immune evasion and are promising targets in drug development.

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Chen, Shun; Yang, Chao; Zhang, Wei; Mahalingam, Suresh; Wang, Mingshu; Cheng, Anchun

2018-05-06

Infections with viruses in the Flaviviridae family have a vast global and economic impact because of the high morbidity and mortality. The pathogenesis of Flaviviridae infections is very complex and not fully understood because these viruses can inhibit multiple immune pathways including the complement system, NK cells, and IFN induction and signalling pathways. The non-structural (NS) 5 and 5A proteins of Flaviviridae viruses are highly conserved and play an important role in resisting host immunity through various evasion mechanisms. This review summarizes the strategies used by the NS5 and 5A proteins of Flaviviridae viruses for evading the innate immune response by inhibiting pattern recognition receptor (PRR) signalling pathways (TLR/MyD88, IRF7), suppressing interferon (IFN) signalling pathways (IFN-γRs, STAT1, STAT2), and impairing the function of IFN-stimulated genes (ISGs) (e.g. protein kinase R [PKR], oligoadenylate synthase [OAS]). All of these immune evasion mechanisms depend on the interaction of NS5 or NS5A with cellular proteins, such as MyD88 and IRF7, IFN-αRs, IFN-γRs, STAT1, STAT2, PKR and OAS. NS5 is the most attractive target for the discovery of broad spectrum compounds against Flaviviridae virus infection. The methyltransferase (MTase) and RNA-dependent RNA polymerase (RdRp) activities of NS5 are the main therapeutic targets for antiviral drugs against Flaviviridae virus infection. Based on our site mapping, the sites involved in immune evasion provide some potential and promising targets for further novel antiviral therapeutics. Copyright © 2018 Elsevier Inc. All rights reserved.

Immunization with a dominant-negative recombinant Herpes Simplex Virus (HSV type 1 protects against HSV-2 genital disease in guinea pigs

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Brans Richard

2010-06-01

Full Text Available Abstract Background CJ9-gD is a novel dominant-negative recombinant herpes simplex virus type 1 (HSV-1 that is completely replication-defective, cannot establish detectable latent infection in vivo, and expresses high levels of the major HSV-1 antigen glycoprotein D immediately following infection. In the present study, CJ9-gD was evaluated as a vaccine against HSV-2 genital infection in guinea pigs. Results Animals immunized with CJ9-gD developed at least 700-fold higher titers of HSV-2-specific neutralization antibodies than mock-immunized controls. After challenge with wild-type HSV-2, all 10 control guinea pigs developed multiple genital lesions with an average of 21 lesions per animal. In contrast, only 2 minor lesions were found in 2 of 8 CJ9-gD-immunized animals, representing a 40-fold reduction on the incidence of primary genital lesions in immunized animals (p Conclusions Collectively, we demonstrate that vaccination with the HSV-1 recombinant CJ9-gD elicits strong and protective immune responses against primary and recurrent HSV-2 genital disease and significantly reduces the extent of latent infection.

NS Segment of a 1918 Influenza A Virus-Descendent Enhances Replication of H1N1pdm09 and Virus-Induced Cellular Immune Response in Mammalian and Avian Systems

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Petersen, Henning; Mostafa, Ahmed; Tantawy, Mohamed A.; Iqbal, Azeem A.; Hoffmann, Donata; Tallam, Aravind; Selvakumar, Balachandar; Pessler, Frank; Beer, Martin; Rautenschlein, Silke; Pleschka, Stephan

2018-01-01

The 2009 pandemic influenza A virus (IAV) H1N1 strain (H1N1pdm09) has widely spread and is circulating in humans and swine together with other human and avian IAVs. This fact raises the concern that reassortment between H1N1pdm09 and co-circulating viruses might lead to an increase of H1N1pdm09 pathogenicity in different susceptible host species. Herein, we explored the potential of different NS segments to enhance the replication dynamics, pathogenicity and host range of H1N1pdm09 strain A/Giessen/06/09 (Gi-wt). The NS segments were derived from (i) human H1N1- and H3N2 IAVs, (ii) highly pathogenic- (H5- or H7-subtypes) or (iii) low pathogenic avian influenza viruses (H7- or H9-subtypes). A significant increase of growth kinetics in A549 (human lung epithelia) and NPTr (porcine tracheal epithelia) cells was only noticed in vitro for the reassortant Gi-NS-PR8 carrying the NS segment of the 1918-descendent A/Puerto Rico/8/34 (PR8-wt, H1N1), whereas all other reassortants showed either reduced or comparable replication efficiencies. Analysis using ex vivo tracheal organ cultures of turkeys (TOC-Tu), a species susceptible to IAV H1N1 infection, demonstrated increased replication of Gi-NS-PR8 compared to Gi-wt. Also, Gi-NS-PR8 induced a markedly higher expression of immunoregulatory and pro-inflammatory cytokines, chemokines and interferon-stimulated genes in A549 cells, THP-1-derived macrophages (dHTP) and TOC-Tu. In vivo, Gi-NS-PR8 induced an earlier onset of mortality than Gi-wt in mice, whereas, 6-week-old chickens were found to be resistant to both viruses. These data suggest that the specific characteristics of the PR8 NS segments can impact on replication, virus induced cellular immune responses and pathogenicity of the H1N1pdm09 in different avian and mammalian host species. PMID:29623073

Is vitamin D deficiency involved in the immune reconstitution inflammatory syndrome?

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Moreno-Reyes Rodrigo

2009-04-01

Full Text Available Abstract Background About 20–30% of persons with HIV infection, especially those living in countries with limited resources, experience an immune reconstitution inflammatory syndrome (IRIS after starting antiretroviral treatment. The active form of vitamin D, 1,25-dihydroxyvitamin D, is a key player in the clearance of pathogens and influences the level of inflammation and macrophage activation. Presentation of the hypothesis We hypothesize that low availability of 1,25-dihydroxyvitamin D, either due to vitamin D deficiency or due to polymorphisms in the vitamin D receptor or in its activating/inactivating enzymes, contributes to the appearance of IRIS. Furthermore, drug interactions with the enzymatic pathways of vitamin D could favour the development of IRIS. Testing the hypothesis Our hypothesis could be explored by a case-control study to assess the prevalence of vitamin D deficiency in HIV-infected patients on antiretroviral treatment who develop and do not develop IRIS. Implications of the hypothesis If the role of vitamin D in IRIS is confirmed, we would be able to screen patients at risk for IRIS by screening for vitamin D deficiency. After confirmation by means of a clinical trial, vitamin D supplementation could be a cheap and safe way to reduce the incidence of IRIS.

Systems Biology of Immune Response to Live and Inactivated Dengue Virus Vaccines

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2017-09-01

AWARD NUMBER: W81XWH-16-2-0032 TITLE: Systems Biology of Immune Response to Live and Inactivated Dengue Virus Vaccines PRINCIPAL INVESTIGATOR...CONTRACT NUMBER Systems Biology of Immune Response to Live and Inactivated Dengue Virus Vaccines 5b. GRANT NUMBER W81XWH-16-2-0032 5c. PROGRAM ELEMENT...cell) responses will be measured using molecular and cellular approaches and the data analyzed using a systems biology approach. During the first

Immune response in domestic ducks following intradermal delivery of inactivated vaccine against H5N1 highly pathogenic avian influenza virus adjuvanted with oligodeoxynucleotides containing CpG motifs.

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Yuk, Seong-Su; Lee, Dong-Hun; Park, Jae-Keun; To, Eredene-Ochir; Kwon, Jung-Hoon; Noh, Jin-Yong; Gomis, Susantha; Song, Chang-Seon

2015-08-01

Ducks are a natural reservoir for H5N1 highly pathogenic avian influenza (HPAI) viruses, which produces a range of clinical outcomes from asymptomatic infections to severe disease with mortality. Vaccination against HPAI is one of the few methods available for controlling avian influenza virus (AIV) infection in domestic ducks; therefore, it is necessary to improve vaccine efficacy against HPAI in domestic ducks. However, few studies have focused on enhancing the immune response by testing alternative administration routes and adjuvants. While attempting to maximize the efficacy of a vaccine, it is important to select an appropriate vaccine delivery route and adjuvant to elicit an enhanced immune response. Although several studies have indicated that the vaccination of ducks against HPAI viruses has offered protection against lethal virus challenge, the immunogenicity of the vaccine still requires improvement. In this study, we characterized the immune response following a novel vaccination strategy against H5N1 HPAI virus in domestic ducks. Our novel intradermal delivery system and the application of the cytosine-phosphodiester-guanine (CpG) oligodeoxynucleotide (ODN) adjuvant allowed us to obtain information regarding the sustained vaccine immunity. Compared with the intramuscular route of vaccination, the intradermal route resulted in higher antibody titer as well as lower antibody deviation following secondary vaccination. In addition, the use of a CpG-ODN adjuvant had a dose-sparing effect on antibody titer. Furthermore, when a high dose of antigen was used, the CpG-ODN-adjuvanted vaccine maintained a high mean antibody titer. This data demonstrates that intradermal immunization combined with administration of CpG-ODN as an adjuvant may be a promising strategy for improving vaccine efficacy in domestic ducks. © 2015 Poultry Science Association Inc.

Inborn errors of human STAT1: allelic heterogeneity governs the diversity of immunological and infectious phenotypes

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Boisson-Dupuis, Stephanie; Kong, Xiao-Fei; Okada, Satoshi; Cypowyj, Sophie; Puel, Anne; Abel, Laurent; Casanova, Jean-Laurent

2012-01-01

The genetic dissection of various human infectious diseases has led to the definition of inborn errors of human STAT1 immunity of four types, including (i) autosomal recessive (AR) complete STAT1 deficiency, (ii) AR partial STAT1 deficiency, (iii) autosomal dominant (AD) STAT1 deficiency, and (iv) AD gain of STAT1 activity. The two types of AR STAT1 defect give rise to a broad infectious phenotype with susceptibility to intramacrophagic bacteria (mostly mycobacteria) and viruses (herpes viruses at least), due principally to the impairment of IFN-γ-mediated and IFN-α/β-mediated immunity, respectively. Clinical outcome depends on the extent to which the STAT1 defect decreases responsiveness to these cytokines. AD STAT1 deficiency selectively predisposes individuals to mycobacterial disease, owing to the impairment of IFN-γ-mediated immunity, as IFN-α/β-mediated immunity is maintained. Finally, AD gain of STAT1 activity is associated with autoimmunity, probably owing to an enhancement of IFN-α/β-mediated immunity. More surprisingly, it is also associated with chronic mucocutaneous candidiasis, through as yet undetermined mechanisms involving an inhibition of the development of IL-17-producing T cells. Thus, germline mutations in human STAT1 define four distinct clinical disorders. Various combinations of viral, mycobacterial and fungal infections are therefore allelic at the human STAT1 locus. These experiments of Nature neatly highlight the clinical and immunological impact of the human genetic dissection of infectious phenotypes. PMID:22651901

Club cells surviving influenza A virus infection induce temporary nonspecific antiviral immunity.

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Hamilton, Jennifer R; Sachs, David; Lim, Jean K; Langlois, Ryan A; Palese, Peter; Heaton, Nicholas S

2016-04-05

A brief window of antigen-nonspecific protection has been observed after influenza A virus (IAV) infection. Although this temporary immunity has been assumed to be the result of residual nonspecific inflammation, this period of induced immunity has not been fully studied. Because IAV has long been characterized as a cytopathic virus (based on its ability to rapidly lyse most cell types in culture), it has been a forgone conclusion that directly infected cells could not be contributing to this effect. Using a Cre recombinase-expressing IAV, we have previously shown that club cells can survive direct viral infection. We show here not only that these cells can eliminate all traces of the virus and survive but also that they acquire a heightened antiviral response phenotype after surviving. Moreover, we experimentally demonstrate temporary nonspecific viral immunity after IAV infection and show that surviving cells are required for this phenotype. This work characterizes a virally induced modulation of the innate immune response that may represent a new mechanism to prevent viral diseases.

Differential reactivity of immune sera from human vaccinees with field strains of eastern equine encephalitis virus.

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Strizki, J M; Repik, P M

1995-11-01

Eastern equine encephalitis (EEE) virus is a mosquito-borne alphavirus that can produce a severe and often fatal acute encephalitis in humans, with significant neurologic sequelae in survivors. Due to the serious nature of the disease, an investigational inactivated EEE vaccine (PE-6) is available to individuals at risk for infection. Both serologic and recent molecular analyses of EEE viruses have demonstrated marked differences between the two antigenic varieties of EEE virus, designated North American (NA) and South American (SA). In view of these findings, we have examined the reactivity of sera from three individuals immunized with the EEE vaccine, derived from an NA isolate, with field strains of EEE virus. Anti-EEE serum antibodies from vaccinees reacted strongly in Western blot assays with both of the envelope (E1 and E2) glycoproteins of each NA strain examined, while reactivities with the glycoproteins of SA strains were substantially weaker and variable and dependent upon both the immune response of the vaccinee and the virus isolate assayed. Most striking was the modest to virtual lack of reactivity with the E2 protein of SA strains. Antigenic differences among the glycoproteins of EEE viruses were not as pronounced in immunoprecipitation analysis. Most significantly, although human immune sera displayed high neutralizing titers against each of the NA isolates examined, only negligible neutralizing titers were obtained against SA isolates. These data suggest that immunized individuals would mount an effective antibody response against infection with NA strains of EEE virus, but that further investigation is clearly warranted to fully assess the protective capability of the vaccine against infection with SA strains.

Circulating intercellular adhesion molecule-1 (ICAM-1) as an early and sensitive marker for virus-induced T cell activation

DEFF Research Database (Denmark)

Christensen, Jan Pravsgaard; Johansen, J; Marker, O

1995-01-01

mice, clearly demonstrating that T cells were mandatory. Analysis of MHC class I and MHC class II-deficient mice revealed that either CD4+ or CD8+ T cells alone are sufficient, despite a markedly reduced inflammatory exudate in the former animals. These results indicate that virus-activated T cells......The effect of systemic virus infection on the level of circulating ICAM-1 (cICAM-1) in serum, and the role of virus-activated T cells in this context, were studied using the murine lymphocytic choriomeningitis virus infection as primary model system. A marked virus-induced elevation in cICAM-1...... in serum was revealed, the presence of which coincided with the phase of virus-induced T cell activation. However, high levels of cICAM-1 in serum were observed well before maximal T cell activation could be demonstrated. No increase in cICAM-1 was observed in the serum of infected T cell-deficient nude...

Effectiveness and safety of traditional Chinese medicine in treating acquired immune deficiency syndrome: 2004-2014.

Science.gov (United States)

Liu, Zhi-Bin; Yang, Ji-Ping; Xu, Li-Ran

2015-12-23

Substantial progress has been made in China in using traditional Chinese medicine (TCM) to treat acquired immune deficiency syndrome (AIDS). Our objective was to review the latest developments in TCM treatment of AIDS in China between 2004 and 2014. We reviewed the content of original articles investigating the efficacy and safety of TCM for treating AIDS published in Chinese and English language journals. Relevant references from 2004 to 2014 were found using PubMed and the China National Knowledge Infrastructure Database. We found that TCM has been widely used for treating AIDS and its complications in China. The number of TCM studies has increased, which indicates efficacy and safety. Measures of efficacy in the reviewed articles included the alleviation of human immunodeficiency virus (HIV)-related signs and symptoms, improvements in quality of life, improvements in long-term survival, counteraction of the adverse side effects of antiviral drugs, promotion of immune reconstitution, and improvement of laboratory results. In sum, the literature indicates that TCM is safe. TCM plays an important role in the treatment of AIDS. Some studies have attempted to measure the efficacy and safety of TCM for treating AIDS, but more evidence is needed. Therefore, more research on this topic is required in the future.

Molecular Mechanisms of Innate Immune Inhibition by Non-Segmented Negative-Sense RNA Viruses

Energy Technology Data Exchange (ETDEWEB)

Chatterjee, Srirupa; Basler, Christopher F.; Amarasinghe, Gaya K.; Leung, Daisy W.

2016-08-01

The host innate immune system serves as the first line of defense against viral infections. Germline-encoded pattern recognition receptors detect molecular patterns associated with pathogens and activate innate immune responses. Of particular relevance to viral infections are those pattern recognition receptors that activate type I interferon responses, which establish an antiviral state. The order Mononegavirales is composed of viruses that possess single-stranded, non-segmented negative-sense (NNS) RNA genomes and are important human pathogens that consistently antagonize signaling related to type I interferon responses. NNS viruses have limited encoding capacity compared to many DNA viruses, and as a likely consequence, most open reading frames encode multifunctional viral proteins that interact with host factors in order to evade host cell defenses while promoting viral replication. In this review, we will discuss the molecular mechanisms of innate immune evasion by select NNS viruses. A greater understanding of these interactions will be critical in facilitating the development of effective therapeutics and viral countermeasures.

How We Manage Adenosine Deaminase-Deficient Severe Combined Immune Deficiency (ADA SCID).

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Kohn, Donald B; Gaspar, H Bobby

2017-05-01

Adenosine deaminase-deficient severe combined immune deficiency (ADA SCID) accounts for 10-15% of cases of human SCID. From what was once a uniformly fatal disease, the prognosis for infants with ADA SCID has improved greatly based on the development of multiple therapeutic options, coupled with more frequent early diagnosis due to implementation of newborn screening for SCID. We review the various treatment approaches for ADA SCID including allogeneic hematopoietic stem cell transplantation (HSCT) from a human leukocyte antigen-matched sibling or family member or from a matched unrelated donor or a haplo-identical donor, autologous HSCT with gene correction of the hematopoietic stem cells (gene therapy-GT), and enzyme replacement therapy (ERT) with polyethylene glycol-conjugated adenosine deaminase. Based on growing evidence of safety and efficacy from GT, we propose a treatment algorithm for patients with ADA SCID that recommends HSCT from a matched family donor, when available, as a first choice, followed by GT as the next option, with allogeneic HSCT from an unrelated or haplo-identical donor or long-term ERT as other options.

Antitumor immunity is defective in T cell-specific microRNA-155-deficient mice and is rescued by immune checkpoint blockade.

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Huffaker, Thomas B; Lee, Soh-Hyun; Tang, William W; Wallace, Jared A; Alexander, Margaret; Runtsch, Marah C; Larsen, Dane K; Thompson, Jacob; Ramstead, Andrew G; Voth, Warren P; Hu, Ruozhen; Round, June L; Williams, Matthew A; O'Connell, Ryan M

2017-11-10

MicroRNA-155 (miR-155) regulates antitumor immune responses. However, its specific functions within distinct immune cell types have not been delineated in conditional KO mouse models. In this study, we investigated the role of miR-155 specifically within T cells during the immune response to syngeneic tumors. We found that miR-155 expression within T cells is required to limit syngeneic tumor growth and promote IFNγ production by T cells within the tumor microenvironment. Consequently, we found that miR-155 expression by T cells is necessary for proper tumor-associated macrophage expression of IFNγ-inducible genes. We also found that immune checkpoint-blocking (ICB) antibodies against programmed cell death protein 1/programmed death ligand 1 (PD-1/PD-L1) and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) restored antitumor immunity in miR-155 T cell-conditional KO mice. We noted that these ICB antibodies rescued the levels of IFNγ-expressing T cells, expression of multiple activation and effector genes expressed by tumor-infiltrating CD8 + and CD4 + T cells, and tumor-associated macrophage activation. Moreover, the ICB approach partially restored expression of several derepressed miR-155 targets in tumor-infiltrating, miR-155-deficient CD8 + T cells, suggesting that miR-155 and ICB regulate overlapping pathways to promote antitumor immunity. Taken together, our findings highlight the multifaceted role of miR-155 in T cells, in which it promotes antitumor immunity. These results suggest that the augmentation of miR-155 expression could be used to improve anticancer immunotherapies. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Dynamic gene expression analysis in a H1N1 influenza virus mouse pneumonia model.

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Bao, Yanyan; Gao, Yingjie; Shi, Yujing; Cui, Xiaolan

2017-06-01

H1N1, a major pathogenic subtype of influenza A virus, causes a respiratory infection in humans and livestock that can range from a mild infection to more severe pneumonia associated with acute respiratory distress syndrome. Understanding the dynamic changes in the genome and the related functional changes induced by H1N1 influenza virus infection is essential to elucidating the pathogenesis of this virus and thereby determining strategies to prevent future outbreaks. In this study, we filtered the significantly expressed genes in mouse pneumonia using mRNA microarray analysis. Using STC analysis, seven significant gene clusters were revealed, and using STC-GO analysis, we explored the significant functions of these seven gene clusters. The results revealed GOs related to H1N1 virus-induced inflammatory and immune functions, including innate immune response, inflammatory response, specific immune response, and cellular response to interferon-beta. Furthermore, the dynamic regulation relationships of the key genes in mouse pneumonia were revealed by dynamic gene network analysis, and the most important genes were filtered, including Dhx58, Cxcl10, Cxcl11, Zbp1, Ifit1, Ifih1, Trim25, Mx2, Oas2, Cd274, Irgm1, and Irf7. These results suggested that during mouse pneumonia, changes in the expression of gene clusters and the complex interactions among genes lead to significant changes in function. Dynamic gene expression analysis revealed key genes that performed important functions. These results are a prelude to advancements in mouse H1N1 influenza virus infection biology, as well as the use of mice as a model organism for human H1N1 influenza virus infection studies.

Giving It Our Best Shot? Human Papillomavirus and Hepatitis B Virus Immunization Among Refugees, Massachusetts, 2011-2013.

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Berman, Rachel Stein; Smock, Laura; Bair-Merritt, Megan H; Cochran, Jennifer; Geltman, Paul L

2017-06-22

The receipt rate of hepatitis B virus vaccine among adolescents in the United States is high, while the receipt rate of human papillomavirus vaccine is low. Rates have not been closely studied among refugees, whose home countries have high rates of disease caused by these viruses. We examined human papillomavirus and hepatitis B virus immunization rates among 2,269 refugees aged 9 to 26 years who resettled in Massachusetts from 2011 through 2013. This was a secondary analysis of data from their medical screenings. We used binary logistic regression to assess characteristics associated with immunization and bivariate analyses to compare refugee immunization rates with those of the general US population. Forty-five percent of US adolescents aged 13 to 17 years received 1 dose of human papillomavirus vaccine, compared with 68% of similarly aged refugees. Males (adjusted odds ratio [aOR], 0.62; 95% confidence interval [CI], 0.52-0.74), refugees older than 13 years (aOR, 0.74; 95% CI, 0.60-0.93), and refugees not from Sub-Saharan Africa (aOR, 0.74; 95% CI, 0.59-0.92) were less likely to receive human papillomavirus vaccine, while arrivals in 2012 through 2013 were more likely (aOR, 1.6; 95% CI, 1.3-1.9) than those arriving in 2011. Refugees older than 13 years were less likely to receive 2 doses of hepatitis B virus vaccine (aOR, 0.49; 95% CI, 0.37-0.63) than older refugees. Specialized post-arrival health assessment may improve refugees' immunization rates.

[Intestinal disorder of anaerobic bacteria aggravates pulmonary immune pathological injury of mice infected with influenza virus].

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Wu, Sha; Yan, Yuqi; Zhang, Mengyuan; Shi, Shanshan; Jiang, Zhenyou

2016-04-01

To investigate the relationship between the intestinal disorder of anaerobic bacteria and influenza virus infection, and the effect on pulmonary inflammatory cytokines in mice. Totally 36 mice were randomly divided into normal control group, virus-infected group and metronidazole treatment group (12 mice in each group). Mice in the metronidazole group were administrated orally with metronidazole sulfate for 8 days causing anaerobic bacteria flora imbalance; then all groups except the normal control group were treated transnasally with influenza virus (50 μL/d FM1) for 4 days to establish the influenza virus-infected models. Their mental state and lung index were observed, and the pathological morphological changes of lung tissues, caecum and intestinal mucosa were examined by HE staining. The levels of interleukin 4 (IL-4), interferon γ (IFN-γ), IL-10 and IL-17 in the lung homogenates were determined by ELISA. Compared with the virus control group, the metronidazole group showed obviously increased lung index and more serious pathological changes of the lung tissue and appendix inflammation performance. After infected by the FM1 influenza virus, IFN-γ and IL-17 of the metronidazole group decreased significantly and IL-4 and IL-10 levels were raised, but there was no statistically difference between the metronidazole and virus control groups. Intestinal anaerobic bacteria may inhibit the adaptive immune response in the lungs of mice infected with FM1 influenza virus through adjusting the lung inflammatory factors, affect the replication and clean-up time of the FM1 influenza virus, thus further aggravating pulmonary immune pathological injury caused by the influenza virus infection.

Universal immunity to influenza must outwit immune evasion

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Sergio Manuel Quinones-Parra

2014-06-01

Full Text Available Although an influenza vaccine has been available for 70 years, influenza virus still causes seasonal epidemics and worldwide pandemics. Currently available vaccines elicit strain-specific antibody responses to the surface haemagglutinin (HA and neuraminidase (NA proteins, but these can be ineffective against serologically-distinct viral variants and novel subtypes. Thus, there is a need for cross-protective or universal influenza vaccines to overcome the necessity for annual immunisation against seasonal influenza and to provide immunity to reduce the severity of infection with pandemic or outbreak viruses. It is well established that natural influenza infection can provide cross-reactive immunity that can reduce the impact of infection with distinct influenza type A strains and subtypes, including H1N1, H3N2, H2N2, H5N1 and H7N9. The key to generating universal influenza immunity via vaccination is to target functionally-conserved regions of the virus, which include epitopes on the internal proteins for cross-reactive T cell immunity or on the HA stem for broadly reactive antibody responses. In the wake of the 2009 H1N1 pandemic, broadly neutralizing antibodies have been characterized and isolated from convalescent and vaccinated individuals, inspiring development of new vaccination techniques to elicit such responses. Induction of influenza-specific T cell responses through vaccination has also been examined in clinical trials. Strong evidence is available from human and animal models of influenza to show that established influenza-specific T cell memory can reduce viral shedding and symptom severity. However, the published evidence also shows that CD8+ T cells can efficiently select immune escape mutants early after influenza virus infection. Here, we discuss universal immunity to influenza viruses mediated by both cross-reactive T cells and antibodies, the mechanisms of immune evasion in influenza, and how to counteract commonly occurring

Association between vitamin D deficiency and pre-existing resistance-associated hepatitis C virus NS5A variants.

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Okubo, Tomomi; Atsukawa, Masanori; Tsubota, Akihito; Shimada, Noritomo; Abe, Hiroshi; Yoshizawa, Kai; Arai, Taeang; Nakagawa, Ai; Itokawa, Norio; Kondo, Chisa; Aizawa, Yoshio; Iwakiri, Katsuhiko

2017-06-01

Although interferon-free therapy with direct-acting antivirals has developed as a standard of care for chronic hepatitis C, the existence of resistance-associated variants (RAVs) has a negative impact on treatment results. Recently, several studies indicated a relationship between chronic hepatitis C and serum vitamin D levels. However, the relationship between RAVs at the hepatitis C virus non-structure 5A (NS5A) region and serum vitamin D level has not yet been examined. Among patients with genotype 1 chronic hepatitis C who were enrolled in a multicenter cooperative study, our subjects comprised 247 patients in whom it was possible to measure RAVs at the NS5A region. These RAVs were measured using a direct sequencing method. The median age of patients was 70 years (range, 24-87 years), and the number of female patients was 135 (54.7%). The median serum 25(OH) D3 level was 22 ng/mL (range, 6-64 ng/mL). L31 and Y93 RAVs at the NS5A region were detected in 3.7% (9/247) and 13.4% (33/247) of patients, respectively. Multivariate analysis identified vitamin D deficiency (serum 25(OH) D3 ≤ 20 ng/mL) (P = 5.91 × 10⁻ 5 , odds ratio = 5.015) and elderly age (>70 years) (P = 1.85 × 10 -3 , odds ratio = 3.364) as contributing independent factors associated with the presence of the L31 and/or Y93 RAVs. The Y93H RAV was detected in 25.9% (29/112) of patients with a vitamin D deficiency, and in 8.9% (12/135) of those with a serum 25(OH) D3 level >20 ng/mL (P = 4.90 × 10 -3 ). We showed that RAVs at the NS5A region are associated with vitamin D deficiency and elderly age, which may have a negative influence on innate/adaptive immune responses to hepatitis C virus infection. © 2016 The Japan Society of Hepatology.

A new paradigm: innate immune sensing of viruses via the Unfolded Protein Response

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Judith A Smith

2014-05-01

Full Text Available The immune system depends upon combinations of signals to mount appropriate responses: pathogen specific signals in the context of co-stimulatory danger signals drive immune strength and accuracy. Viral infections trigger anti-viral type I interferon (IFN responses by stimulating endosomal and cytosolic pattern recognition receptors (PRRs. However, viruses have also evolved many strategies to counteract IFN responses. Are there intracellular danger signals that enhance immune responses to viruses? During infection, viruses place a heavy demand on the protein folding machinery of the host endoplasmic reticulum (ER. To survive ER stress, host cells mount an Unfolded Protein Response (UPR to decrease ER protein load and enhance protein-folding capacity. Viruses also directly elicit the UPR to enhance their replication. Increasing evidence supports an intersection between the host UPR and inflammation, in particular the production of pro-inflammatory cytokines and type I IFN. The UPR directly activates pro-inflammatory cytokine transcription factors and dramatically enhances cytokine production in response to viral PRR engagement. Additionally, viral PRR engagement may stimulate specific pathways within the UPR to enhance cytokine production. Through these mechanisms, viral detection via the UPR and inflammatory cytokine production are intertwined. Consequently, the UPR response is perfectly poised to act as an infection-triggered danger signal. The UPR may serve as an internal co-stimulatory signal that 1 provides specificity and 2 critically augments responses to overcome viral subterfuge. Further work is needed to test this hypothesis during viral infections.

Intestinal Irradiation and Fibrosis in a Th1-Deficient Environment

International Nuclear Information System (INIS)

Linard, Christine; Billiard, Fabienne; Benderitter, Marc

2012-01-01

Purpose: Changes in the Th1/Th2 immune balance may play a role in increasing the incidence of radiation-induced toxicity. This study evaluates the consequences of Th1 deficiency on intestinal response (fibrosis and T cell trafficking) to abdominal irradiation and examines in mucosa and mesenteric lymph nodes (MLN) the differential involvement of the two Th1 pathways, T-bet/STAT1 and IL-12/STAT4, in controlling this balance in mice. Methods and Materials: Using T-bet-deficient mice (T-bet −/− ), we evaluated the mRNA and protein expression of the Th1 pathways (IFN-γ, T-bet/STAT1, and IL-12/STAT4) and the CD4 + and CD8 + populations in ileal mucosa and MLN during the first 3 months after 10 Gy abdominal irradiation. Results: The T-bet-deficient mice showed an increased fibrotic response to radiation, characterized by higher TGF-β1, col3a1 expression, and collagen deposition in mucosa compared with wild-type mice. This response was associated with drastically lower expression of IFN-γ, the hallmark Th1 cytokine. Analysis of the Th1 expression pathways, T-bet/STAT1 and IL-12/STAT4, showed their equal involvement in the failure of Th1 polarization. A minimal IFN-γ level depended on the IL-23-p19/STAT4 level. In addition, the radiation-induced deficiency in the priming of Th1 by IFN-γ was related to the defective homing capacity of CD8 + cells in the mucosa. Conclusion: Irradiation induces Th2 polarization, and the Th2 immune response may play a role in potentiating irradiation-induced intestinal collagen deposition.

Strategies and challenges for eliciting immunity against avian influenza virus in birds.

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Swayne, David E; Kapczynski, Darrell

2008-10-01

Vaccines and vaccination have emerged during the past two decades as essential tools in avian influenza (AI) control for poultry, because they increase resistance to infection, prevent illness and death, reduce virus replication and shed from respiratory and alimentary tracts, and reduce virus transmission to birds and mammals, including humans. Such protection in birds is primarily mediated by homosubtypic humoral immunity against the hemagglutinin protein, but cell-mediated and innate immunity contribute to protection in some bird species. The immune response to the neuraminidase protein can contribute to protection, but immunity to the viral internal proteins is generally not protective. Although, some preliminary studies with M2e protein in chickens suggest partial protection may be achievable. Historically, the H5 subtype AI vaccines have demonstrated broad homosubtypic protection, primarily against H5 high-pathogenicity (HP) AI viruses isolated in the early stages of outbreaks. However, as H5 viruses have become endemic and outbreaks prolonged, some drift variants with resistance to earlier H5 AI vaccines have emerged in Central America, China, Egypt, and Indonesia. How widespread such drift variants are will remain unknown until more detailed genetic and antigenic analyses are conducted on field isolates. Future vaccines will utilize biotechnology to produce new AI vaccine seed strains using HA genes more closely matching circulating field viruses. In addition, newer technologies for AI vaccines will improve vaccine coverage by using mass application technologies for example by drinking water, by spray, or via injection in ovo or at the hatchery.

Ebola Virus Glycoprotein Induces an Innate Immune Response In vivo via TLR4

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Chih-Yun Lai

2017-08-01

Full Text Available Ebola virus (EBOV, a member of the Filoviridae family, causes the most severe form of viral hemorrhagic fever. Although no FDA licensed vaccine or treatment against Ebola virus disease (EVD is currently available, Ebola virus glycoprotein (GP is the major antigen used in all candidate Ebola vaccines. Recent reports of protection as quickly as within 6 days of administration of the rVSV-based vaccine expressing EBOV GP before robust humoral responses were generated suggests that the innate immune responses elicited early after vaccination may contribute to the protection. However, the innate immune responses induced by EBOV GP in the absence of viral vectors or adjuvants have not been fully characterized in vivo. Our recent studies demonstrated that immunization with highly purified recombinant GP in the absence of adjuvants induced a robust IgG response and partial protection against EBOV infection suggesting that GP alone can induce protective immunity. In this study we investigated the early immune response to purified EBOV GP alone in vitro and in vivo. We show that GP was efficiently internalized by antigen presenting cells and subsequently induced production of key inflammatory cytokines. In vivo, immunization of mice with EBOV GP triggered the production of key Th1 and Th2 innate immune cytokines and chemokines, which directly governed the recruitment of CD11b+ macrophages and CD11c+ dendritic cells to the draining lymph nodes (DLNs. Pre-treatment of mice with a TLR4 antagonist inhibited GP-induced cytokine production and recruitment of immune cells to the DLN. EBOV GP also upregulated the expression of costimulatory molecules in bone marrow derived macrophages suggesting its ability to enhance APC stimulatory capacity, which is critical for the induction of effective antigen-specific adaptive immunity. Collectively, these results provide the first in vivo evidence that early innate immune responses to EBOV GP are mediated via the TLR4

Epstein–Barr Virus and Hemophagocytic Lymphohistiocytosis

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Rebecca A. Marsh

2018-01-01

Full Text Available Epstein–Barr virus (EBV is a ubiquitous virus that infects nearly all people worldwide without serious sequela. However, for patients who have genetic diseases which predispose them to the development of hemophagocytic lymphohistiocytosis (HLH, EBV infection is a life-threatening problem. As a part of a themed collection of articles on EBV infection and human primary immune deficiencies, we will review key concepts related to the understanding and treatment of HLH.

Protection against avian metapneumovirus subtype C in turkeys immunized via the respiratory tract with inactivated virus.

Science.gov (United States)

Cha, Ra Mi; Khatri, Mahesh; Sharma, Jagdev M

2011-01-10

Avian metapneumovirus subtype C (aMPV/C) causes a severe upper respiratory tract (URT) infection in turkeys. Turkeys were inoculated oculonasally with inactivated aMPV/C adjuvanted with synthetic double-stranded RNA polyriboinosinic polyribocytidylic acid (Poly IC). Immunized turkeys had elevated numbers of mucosal IgA+ cells in the URT and increased levels of virus-specific IgG and IgA in the lachrymal fluid and IgG in the serum. After 7 or 21 days post immunization, turkeys were challenged oculonasally with pathogenic aMPV/C. Immunized groups were protected against respiratory lesions induced by the challenge virus. Further, the viral copy number of the challenge virus in the URT were significantly lower in the immunized turkeys than in the unimmunized turkeys (P<0.05). These results showed that inactivated aMPV/C administered by the respiratory route induced protective immunity against pathogenic virus challenge. Copyright © 2010 Elsevier Ltd. All rights reserved.

Spinal cord injury-induced immune deficiency syndrome enhances infection susceptibility dependent on lesion level.

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Brommer, Benedikt; Engel, Odilo; Kopp, Marcel A; Watzlawick, Ralf; Müller, Susanne; Prüss, Harald; Chen, Yuying; DeVivo, Michael J; Finkenstaedt, Felix W; Dirnagl, Ulrich; Liebscher, Thomas; Meisel, Andreas; Schwab, Jan M

2016-03-01

Pneumonia is the leading cause of death after acute spinal cord injury and is associated with poor neurological outcome. In contrast to the current understanding, attributing enhanced infection susceptibility solely to the patient's environment and motor dysfunction, we investigate whether a secondary functional neurogenic immune deficiency (spinal cord injury-induced immune deficiency syndrome, SCI-IDS) may account for the enhanced infection susceptibility. We applied a clinically relevant model of experimental induced pneumonia to investigate whether the systemic SCI-IDS is functional sufficient to cause pneumonia dependent on spinal cord injury lesion level and investigated whether findings are mirrored in a large prospective cohort study after human spinal cord injury. In a mouse model of inducible pneumonia, high thoracic lesions that interrupt sympathetic innervation to major immune organs, but not low thoracic lesions, significantly increased bacterial load in lungs. The ability to clear the bacterial load from the lung remained preserved in sham animals. Propagated immune susceptibility depended on injury of central pre-ganglionic but not peripheral postganglionic sympathetic innervation to the spleen. Thoracic spinal cord injury level was confirmed as an independent increased risk factor of pneumonia in patients after motor complete spinal cord injury (odds ratio = 1.35, P spinal cord injury directly causes increased risk for bacterial infection in mice as well as in patients. Besides obvious motor and sensory paralysis, spinal cord injury also induces a functional SCI-IDS ('immune paralysis'), sufficient to propagate clinically relevant infection in an injury level dependent manner. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Maternal Antibody-Mediated Disease Enhancement in Type I Interferon-Deficient Mice Leads to Lethal Disease Associated with Liver Damage.

Directory of Open Access Journals (Sweden)

Julia María Martínez Gómez

2016-03-01

Full Text Available Epidemiological studies have reported that most of the severe dengue cases occur upon a secondary heterologous infection. Furthermore, babies born to dengue immune mothers are at greater risk of developing severe disease upon primary infection with a heterologous or homologous dengue virus (DENV serotype when maternal antibodies reach sub-neutralizing concentrations. These observations have been explained by the antibody mediated disease enhancement (ADE phenomenon whereby heterologous antibodies or sub-neutralizing homologous antibodies bind to but fail to neutralize DENV particles, allowing Fc-receptor mediated entry of the virus-antibody complexes into host cells. This eventually results in enhanced viral replication and heightened inflammatory responses. In an attempt to replicate this ADE phenomenon in a mouse model, we previously reported that upon DENV2 infection 5-week old type I and II interferon (IFN receptors-deficient mice (AG129 born to DENV1-immune mothers displayed enhancement of disease severity characterized by increased virus titers and extensive vascular leakage which eventually led to the animals' death. However, as dengue occurs in immune competent individuals, we sought to reproduce this mouse model in a less immunocompromised background. Here, we report an ADE model that is mediated by maternal antibodies in type I IFN receptor-deficient A129 mice. We show that 5-week old A129 mice born to DENV1-immune mothers succumbed to a DENV2 infection within 4 days that was sub-lethal in mice born to naïve mothers. Clinical manifestations included extensive hepatocyte vacuolation, moderate vascular leakage, lymphopenia, and thrombocytopenia. Anti-TNFα therapy totally protected the mice and correlated with healthy hepatocytes. In contrast, blocking IL-6 did not impact the virus titers or disease outcome. This A129 mouse model of ADE may help dissecting the mechanisms involved in dengue pathogenesis and evaluate the efficacy of

Human NF-κB1 Haploinsufficiency and Epstein-Barr Virus-Induced Disease-Molecular Mechanisms and Consequences.

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Hoeger, Birgit; Serwas, Nina Kathrin; Boztug, Kaan

2017-01-01

Nuclear factor kappa-light-chain-enhancer of activated B cells 1 (NF-κB1)-related human primary immune deficiencies have initially been characterized as defining a subgroup of common variable immunodeficiencies (CVIDs), representing intrinsic B-cell disorders with antibody deficiency and recurrent infections of various kind. Recent evidence indicates that NF-κB1 haploinsufficiency underlies a variable type of combined immunodeficiency (CID) affecting both B and T lymphocyte compartments, with a broadened spectrum of disease manifestations, including Epstein-Barr virus (EBV)-induced lymphoproliferative disease and immediate life-threatening consequences. As part of this review series focused on EBV-related primary immunodeficiencies, we discuss the current clinical and molecular understanding of monoallelic NFKB1 germline mutations with special focus on the emerging context of EBV-associated disease. We outline mechanistic implications of dysfunctional NF-κB1 in B and T cells and discuss the fatal relation of impaired T-cell function with the inability to clear EBV infections. Finally, we compare common and suggested treatment angles in the context of this complex disease.

Genetics Home Reference: complement component 2 deficiency

Science.gov (United States)

... Topic: Immune System and Disorders Health Topic: Lupus Genetic and Rare Diseases Information Center (1 link) Complement component 2 deficiency Additional NIH Resources (1 link) National Institute of Allergy and Infectious Diseases: Primary Immune Deficiency Diseases Educational Resources (6 ...

Characterization of Ebola virus entry by using pseudotyped viruses: identification of receptor-deficient cell lines.

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Wool-Lewis, R J; Bates, P

1998-04-01

Studies analyzing Ebola virus replication have been severely hampered by the extreme pathogenicity of this virus. To permit analysis of the host range and function of the Ebola virus glycoprotein (Ebo-GP), we have developed a system for pseudotyping these glycoproteins into murine leukemia virus (MLV). This pseudotyped virus, MLV(Ebola), can be readily concentrated to titers which exceed 5 x 10(6) infectious units/ml and is effectively neutralized by antibodies specific for Ebo-GP. Analysis of MLV(Ebola) infection revealed that the host range conferred by Ebo-GP is very broad, extending to cells of a variety of species. Notably, all lymphoid cell lines tested were completely resistant to infection; we speculate that this is due to the absence of a cellular receptor for Ebo-GP on B and T cells. The generation of high-titer MLV(Ebola) pseudotypes will be useful for the analysis of immune responses to Ebola virus infection, development of neutralizing antibodies, analysis of glycoprotein function, and isolation of the cellular receptor(s) for the Ebola virus.

Herd immunity to Newcastle disease virus in broiler flocks in Israel.

Science.gov (United States)

Wiseman, Anat; Berman, Elyakum M

2017-08-01

Due to the ongoing need to protect poultry from virulent Newcastle disease virus, all commercial poultry flocks in Israel are vaccinated according to a defined programme using a combination of live and inactivated vaccines. The vaccination protocol for broilers during the years of the study comprised a live vaccine administered by spray on the day of hatching, inactivated vaccine by subcutaneous injection at 10-12 days of age, and another live vaccine given by aerosol at 17-21 days of age. A cross-sectional study was designed in order to examine the influence of herd immunity on the risk of Newcastle disease outbreak in broiler flocks. The study was based on the extensive field data kept in the Poultry Health Laboratories database. The results of serology tests employing haemagglutination inhibition for Newcastle disease virus were analysed and crossed with the list of flocks that had been diagnosed with ND in the years 2007-2014. At the peak of induced immunization (fifth week of growth), 87.5% of the tested flocks had achieved herd immunity (≥85% of birds in the flock with an HI titre ≥4). Based on a logistic regression model, the odds ratio for ND in flocks without herd immunity was 3.7 (95% CI 1.8-7.3, P-value < 0.001). The higher the percentage of birds with low HI titres the higher the risk of ND outbreak. Under field conditions, herd immunity is an important indicator for the risk of ND outbreak.

Intradermal immunization with inactivated swine influenza virus and adjuvant polydi(sodium carboxylatoethylphenoxy)phosphazene (PCEP) induced humoral and cell-mediated immunity and reduced lung viral titres in pigs.

Science.gov (United States)

Magiri, Royford; Lai, Ken; Chaffey, Alyssa; Zhou, Yan; Pyo, Hyun-Mi; Gerdts, Volker; Wilson, Heather L; Mutwiri, George

2018-03-14

Swine influenza virus is endemic worldwide and it is responsible for significant economic losses to the swine industry. A vaccine that stimulates a rapid and long-lasting protective immune response to prevent this infection is highly sought. Poly[di(sodium carboxylatoethylphenoxy)-phosphazene (PCEP) has demonstrated adjuvant activity when formulated as part of multiple vaccines in mice and pigs. In this study we examined the magnitude and type of immune response induced in pigs vaccinated via the intramuscular or intradermal routes with inactivated swine influenza virus (SIV) H1N1 vaccine formulated with PCEP. Intradermal administration of PCEP-adjuvanted inactivated SIV vaccine stimulated significant anti-SIV antibody titres, increased neutralizing antibodies, and significantly reduced lung virus load with limited reduction of gross lung lesions after challenge with virulent H1N1 relative to control animals. These results indicate that PCEP may be effective as a vaccine adjuvant against swine influenza viruses in pigs and should be considered a potential candidate adjuvant for future swine intradermal influenza vaccines. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cutaneous T-cell lymphoma in a patient infected with human immunodeficiency virus type 1. Use of radiation therapy

International Nuclear Information System (INIS)

Goldstein, J.; Becker, N.; DelRowe, J.; Davis, L.

1990-01-01

A patient with cutaneous T-cell lymphoma (CTCL) and acquired immune deficiency syndrome (AIDS) is presented. The patient had a localized lesion on his scalp. Evaluation for systemic lymphoma was negative. A biopsy specimen showed superficial and deep dermal infiltrates of pleomorphic lymphocytes. Immunohistochemistry was consistent with T-cell lymphoma. The patient was treated successfully with local irradiation. He remained free of further systemic and cutaneous recurrences of the lymphoma until he died 8 months after treatment of pneumonia. This case is the first to our knowledge to describe a localized CTCL in a patient infected with human immunodeficiency virus type 1 (HIV-1)

Antibody titers against vaccine and contemporary wild poliovirus type 1 in children immunized with IPV+OPV and young adults immunized with OPV.

Science.gov (United States)

Lukashev, Alexander N; Yarmolskaya, Maria S; Shumilina, Elena Yu; Sychev, Daniil A; Kozlovskaya, Liubov I

2016-02-02

In 2010, a type 1 poliovirus outbreak in Congo with 445 lethal cases was caused by a virus that was neutralized by sera of German adults vaccinated with inactivated polio vaccine with a reduced efficiency. This seroprevalence study was done in two cohorts immunized with other vaccination schedules. Russian children aged 3-6 years immunized with a combination of inactivated and live polio vaccines were reasonably well protected against any wild type poliovirus 1, including the Congolese isolate. Adults aged 20-29 years immunized only with live vaccine were apparently protected against the vaccine strain (92% seropositive), but only 50% had detectable antibodies against the Congo-2010 isolate. Both waning immunity and serological divergence of the Congolese virus could contribute to this result. Copyright © 2015 Elsevier B.V. All rights reserved.

Immunization with lipopolysaccharide-deficient whole cells provides protective immunity in an experimental mouse model of Acinetobacter baumannii infection.

Directory of Open Access Journals (Sweden)

Meritxell García-Quintanilla

Full Text Available The increasing clinical importance of infections caused by multidrug resistant Acinetobacter baumannii warrants the development of novel approaches for prevention and treatment. In this context, vaccination of certain patient populations may contribute to reducing the morbidity and mortality caused by this pathogen. Vaccines against Gram-negative bacteria based on inactivated bacterial cells are highly immunogenic and have been shown to produce protective immunity against a number of bacterial species. However, the high endotoxin levels present in these vaccines due to the presence of lipopolysaccharide complicates their use in human vaccination. In the present study, we used a laboratory-derived strain of A. baumannii that completely lacks lipopolysaccharide due to a mutation in the lpxD gene (IB010, one of the genes involved in the first steps of lipopolysaccharide biosynthesis, for vaccination. We demonstrate that IB010 has greatly reduced endotoxin content (<1.0 endotoxin unit/106 cells compared to wild type cells. Immunization with formalin inactivated IB010 produced a robust antibody response consisting of both IgG1 and IgG2c subtypes. Mice immunized with IB010 had significantly lower post-infection tissue bacterial loads and significantly lower serum levels of the pro-inflammatory cytokines IL-1β, TNF-α and IL-6 compared to control mice in a mouse model of disseminated A. baumannii infection. Importantly, immunized mice were protected from infection with the ATCC 19606 strain and an A. baumannii clinical isolate. These data suggest that immunization with inactivated A. baumannii whole cells deficient in lipopolysaccharide could serve as the basis for a vaccine for the prevention of infection caused by A. baumannii.

Latent Virus Reactivation: From Space to Earth

Science.gov (United States)

Mehta, Satish K.; Cohrs, Randall J.; Gilden, Donald H.; Tyring, Stephen K.; Castro, Victoria A.; Ott, C. Mark; Pierson, Duane L.

2010-01-01

Reactivation of latent viruses is a recognized consequence of decreased immunity. More recently viral reactivation has been identified as an important in vivo indicator of clinically relevant immune changes. Viral reactivation can be determined quickly and easily by the presence of virus in saliva and other body fluids. Real-time polymerase chain reaction (PCR) is a highly sensitive and specific molecular method to detect the presence of specific viral DNA. Studies in astronauts demonstrated that herpes simplex virus type 1(HSV-1), Epstein-Barr Virus (EBV), cytomegalovirus (CMV), and varicella zoster virus (VZV) reactivate at rates above normal during and after spaceflight in response to moderately decreased T-cell immunity. This technology was expanded to patients on Earth beginning with human immune deficiency virus (HIV) immuno-compromised patients. The HIV patients shed EBV in saliva at rates 9-fold higher than observed in astronauts demonstrating that the level of EBV shedding reflects the severity of impaired immunity. Whereas EBV reactivation is not expected to produce serious effects in astronauts on missions of 6 months or less, VZV reactivation in astronauts could produce shingles. Reactivation of live, infectious VZV in astronauts with no symptoms was demonstrated in astronauts during and after spaceflight. We applied our technology to study VZV-induced shingles in patients. In a study of 54 shingles patients, we showed salivary VZV was present in every patient on the day antiviral (acyclovir) treatment was initiated. Pain and skin lesions decreased with antiviral treatment. Corresponding decreases in levels of VZV were also observed and accompanied recovery. Although the level of VZV in shingles patients before the treatment was generally higher than those found in astronauts, lower range of VZV numbers in shingles patients overlapped with astronaut s levels. This suggests a potential risk of shingles to astronauts resulting from reactivation of VZV. In

Synthesis of RNA segment 1-3 during generation of incomplete influenza A (fowl plague) virus

International Nuclear Information System (INIS)

Carter, M.J.; Mahy, B.W.J.

1982-01-01

Incomplete influenza A virus (fowl plague Dobson strain) was prepared by undiluted passage in primary chick embryo fibroblast cells. Analysis of released virus RNA revealed a deficiency in RNA segments 1-3, characteristic of incomplete virus formation. The virus yield from a high multiplicity infection with standard virus always showed this deficiency, even when analysed as early as 6 hours post-infection, whereas infection at low multiplicity gave rise to virus indistinghuishable in RNA composition from the parent virus. The relative amounts of intracellular, non-polyadenylated, complementary RNA (template RNA) were found to reflect accurately the eventual RNA composition of released virus, and were altered in phase with PFU:HAU ratio, throughout a von Magnus cycle. (Author)

Plum pox virus capsid protein suppresses plant pathogen-associated molecular pattern (PAMP)-triggered immunity.

Science.gov (United States)

Nicaise, Valerie; Candresse, Thierry

2017-08-01

The perception of pathogen-associated molecular patterns (PAMPs) by immune receptors launches defence mechanisms referred to as PAMP-triggered immunity (PTI). Successful pathogens must suppress PTI pathways via the action of effectors to efficiently colonize their hosts. So far, plant PTI has been reported to be active against most classes of pathogens, except viruses, although this defence layer has been hypothesized recently as an active part of antiviral immunity which needs to be suppressed by viruses for infection success. Here, we report that Arabidopsis PTI genes are regulated upon infection by viruses and contribute to plant resistance to Plum pox virus (PPV). Our experiments further show that PPV suppresses two early PTI responses, the oxidative burst and marker gene expression, during Arabidopsis infection. In planta expression of PPV capsid protein (CP) was found to strongly impair these responses in Nicotiana benthamiana and Arabidopsis, revealing its PTI suppressor activity. In summary, we provide the first clear evidence that plant viruses acquired the ability to suppress PTI mechanisms via the action of effectors, highlighting a novel strategy employed by viruses to escape plant defences. © 2016 BSPP AND JOHN WILEY & SONS LTD.

Antigenic characterization of small, round-structured viruses by immune electron microscopy.

OpenAIRE

Okada, S; Sekine, S; Ando, T; Hayashi, Y; Murao, M; Yabuuchi, K; Miki, T; Ohashi, M

1990-01-01

Small, round-structured viruses (SRSVs) detected from nonbacterial gastroenteritis outbreaks in Tokyo and Saitama Prefecture, Japan, during the period from 1977 to 1988 were tentatively classified into nine antigenic patterns from SRSV-1 (S-1) to SRSV-9 (S-9) by cross-immune electron microscopy (IEM). S-1 and S-2 appeared pattern specific, while S-3 to S-9, distinguishable from each other in their reactivity, appeared somewhat antigenically related. Their antigenic relatedness to the Norwal, ...

Variability or conservation of hepatitis C virus hypervariable region 1?

Indian Academy of Sciences (India)

The hypervariable region 1 (HVR1) of the E2 protein of hepatitis C virus (HCV) is highly heterogeneous in its primary sequence and is responsible for significant inter- and intra-individual variation of the infecting virus, which may represent an important pathogenetic mechanism leading to immune escape and persistent ...

A replication-deficient rabies virus vaccine expressing Ebola virus glycoprotein is highly attenuated for neurovirulence

International Nuclear Information System (INIS)

Papaneri, Amy B.; Wirblich, Christoph; Cann, Jennifer A.; Cooper, Kurt; Jahrling, Peter B.; Schnell, Matthias J.; Blaney, Joseph E.

2012-01-01

We are developing inactivated and live-attenuated rabies virus (RABV) vaccines expressing Ebola virus (EBOV) glycoprotein for use in humans and endangered wildlife, respectively. Here, we further characterize the pathogenesis of the live-attenuated RABV/EBOV vaccine candidates in mice in an effort to define their growth properties and potential for safety. RABV vaccines expressing GP (RV-GP) or a replication-deficient derivative with a deletion of the RABV G gene (RVΔG-GP) are both avirulent after intracerebral inoculation of adult mice. Furthermore, RVΔG-GP is completely avirulent upon intracerebral inoculation of suckling mice unlike parental RABV vaccine or RV-GP. Analysis of RVΔG-GP in the brain by quantitative PCR, determination of virus titer, and immunohistochemistry indicated greatly restricted virus replication. In summary, our findings indicate that RV-GP retains the attenuation phenotype of the live-attenuated RABV vaccine, and RVΔG-GP would appear to be an even safer alternative for use in wildlife or consideration for human use.

Superior therapeutic efficacy of alphavirus-mediated immunization against human papilloma virus type 16 antigens in a murine tumour model : effects of the route of immunization

NARCIS (Netherlands)

Daemen, T; Riezebos-Brilman, A; Regts, J; Dontje, B; van der Zee, A; Wilschut, J

2004-01-01

In our efforts to develop a strong, effective immune response against cervical carcinoma and premalignant disease, we study the use of recombinant Semliki Forest virus (SFV) encoding the oncoproteins E6 and E7 from high-risk human papilloma viruses (HPVs). Optimal immunization conditions are

Intestinal Irradiation and Fibrosis in a Th1-Deficient Environment

Energy Technology Data Exchange (ETDEWEB)

Linard, Christine, E-mail: christine.linard@irsn.fr [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France); Billiard, Fabienne; Benderitter, Marc [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France)

2012-09-01

Purpose: Changes in the Th1/Th2 immune balance may play a role in increasing the incidence of radiation-induced toxicity. This study evaluates the consequences of Th1 deficiency on intestinal response (fibrosis and T cell trafficking) to abdominal irradiation and examines in mucosa and mesenteric lymph nodes (MLN) the differential involvement of the two Th1 pathways, T-bet/STAT1 and IL-12/STAT4, in controlling this balance in mice. Methods and Materials: Using T-bet-deficient mice (T-bet{sup -/-}), we evaluated the mRNA and protein expression of the Th1 pathways (IFN-{gamma}, T-bet/STAT1, and IL-12/STAT4) and the CD4{sup +} and CD8{sup +} populations in ileal mucosa and MLN during the first 3 months after 10 Gy abdominal irradiation. Results: The T-bet-deficient mice showed an increased fibrotic response to radiation, characterized by higher TGF-{beta}1, col3a1 expression, and collagen deposition in mucosa compared with wild-type mice. This response was associated with drastically lower expression of IFN-{gamma}, the hallmark Th1 cytokine. Analysis of the Th1 expression pathways, T-bet/STAT1 and IL-12/STAT4, showed their equal involvement in the failure of Th1 polarization. A minimal IFN-{gamma} level depended on the IL-23-p19/STAT4 level. In addition, the radiation-induced deficiency in the priming of Th1 by IFN-{gamma} was related to the defective homing capacity of CD8{sup +} cells in the mucosa. Conclusion: Irradiation induces Th2 polarization, and the Th2 immune response may play a role in potentiating irradiation-induced intestinal collagen deposition.

Vaccination against lymphocytic choriomeningitis virus infection in MHC class II-deficient mice

DEFF Research Database (Denmark)

Holst, Peter Johannes; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup

2011-01-01

response could be elicited in MHC class II-deficient mice by vaccination with adenovirus encoding lymphocytic choriomeningitis virus (LCMV) glycoprotein tethered to MHC class II-associated invariant chain. Moreover, the response induced conferred significant cytolytic CD8(+) T cell-mediated protection...... against challenge with a high dose of the invasive clone 13 strain of LCMV. In contrast, vaccination with adenovirus encoding unlinked LCMV glycoprotein induced weak virus control in the absence of CD4(+) T cells, and mice may die of increased immunopathology associated with incomplete protection. Acute...... mortality was not observed in any vaccinated mice following infection with the less-invasive Traub strain. However, LCMV Traub infection caused accelerated late mortality in unvaccinated MHC class II-deficient mice; in this case, we observed a strong trend toward delayed mortality in vaccinated mice...

Contribution of murine innate serum inhibitors toward interference within influenza virus immune assays.

Science.gov (United States)

Cwach, Kevin T; Sandbulte, Heather R; Klonoski, Joshua M; Huber, Victor C

2012-03-01

Prior to detection of an antibody response toward influenza viruses using the hemagglutination inhibition assay (HAI), sera are routinely treated to inactivate innate inhibitors using both heat inactivation (56°C) and recombinant neuraminidase [receptor-destroying enzyme (RDE)]. We revisited the contributions of innate serum inhibitors toward interference with influenza viruses in immune assays, using murine sera, with emphasis on the interactions with influenza A viruses of the H3N2 subtype. We used individual serum treatments: 56°C alone, RDE alone, or RDE + 56°C, to treat sera prior to evaluation within HAI, microneutralization, and macrophage uptake assays. Our data demonstrate that inhibitors present within untreated murine sera interfere with the HAI assay in a manner that is different from that seen for the microneutralization assay. Specifically, the γ class inhibitor α(2) -Macroglobulin (A2-M) can inhibit H3N2 viruses within the HAI assay, but not in the microneutralization assay. Based on these findings, we used a macrophage uptake assay to demonstrate that these inhibitors can increase uptake by macrophages when the influenza viruses express an HA from a 1968 H3N2 virus isolate, but not a 1997 H3N2 isolate. The practice of treating sera to inactivate innate inhibitors of influenza viruses prior to evaluation within immune assays has allowed us to effectively detect influenza virus-specific antibodies for decades. However, this practice has yielded an under-appreciation for the contribution of innate serum inhibitors toward host immune responses against these viruses, including contributions toward neutralization and macrophage uptake. © 2011 Blackwell Publishing Ltd.

Human Leukocyte Antigen (HLA and Immune Regulation: How Do Classical and Non-Classical HLA Alleles Modulate Immune Response to Human Immunodeficiency Virus and Hepatitis C Virus Infections?

Directory of Open Access Journals (Sweden)

Nicole B. Crux

2017-07-01

Full Text Available The genetic factors associated with susceptibility or resistance to viral infections are likely to involve a sophisticated array of immune response. These genetic elements may modulate other biological factors that account for significant influence on the gene expression and/or protein function in the host. Among them, the role of the major histocompatibility complex in viral pathogenesis in particular human immunodeficiency virus (HIV and hepatitis C virus (HCV, is very well documented. We, recently, added a novel insight into the field by identifying the molecular mechanism associated with the protective role of human leukocyte antigen (HLA-B27/B57 CD8+ T cells in the context of HIV-1 infection and why these alleles act as a double-edged sword protecting against viral infections but predisposing the host to autoimmune diseases. The focus of this review will be reexamining the role of classical and non-classical HLA alleles, including class Ia (HLA-A, -B, -C, class Ib (HLA-E, -F, -G, -H, and class II (HLA-DR, -DQ, -DM, and -DP in immune regulation and viral pathogenesis (e.g., HIV and HCV. To our knowledge, this is the very first review of its kind to comprehensively analyze the role of these molecules in immune regulation associated with chronic viral infections.

Humoral and cell-mediated immune responses in DNA immunized mink challenged with wild-type canine distemper virus.

Science.gov (United States)

Nielsen, Line; Søgaard, Mette; Karlskov-Mortensen, Peter; Jensen, Trine Hammer; Jensen, Tove Dannemann; Aasted, Bent; Blixenkrone-Møller, Merete

2009-07-30

The aim of the study was to investigate the different phases of the immune response after DNA immunization with the hemagglutinin and nucleoprotein genes from canine distemper virus (CDV). Although attenuated live CDV vaccines have effectively reduced the incidence of disease, canine distemper is still a problem worldwide. The broad host range of CDV creates a constant viral reservoir among wildlife animals. Our results demonstrated early humoral and cell-mediated immune responses (IFN-gamma) in DNA vaccinated mink compared to mock-vaccinated mink after challenge with a Danish wild-type CDV. The DNA vaccine-induced immunity protected the natural host against disease development.

X-linked immunodeficiency with magnesium defect, Epstein-Barr virus infection, and neoplasia disease: a combined immune deficiency with magnesium defect.

Science.gov (United States)

Ravell, Juan; Chaigne-Delalande, Benjamin; Lenardo, Michael

2014-12-01

To describe the role of the magnesium transporter 1 (MAGT1) in the pathogenesis of 'X-linked immunodeficiency with magnesium defect, Epstein-Barr virus (EBV) infection, and neoplasia' (XMEN) disease and its clinical implications. The magnesium transporter protein MAGT1 participates in the intracellular magnesium ion (Mg) homeostasis and facilitates a transient Mg influx induced by the activation of the T-cell receptor. Loss-of-function mutations in MAGT1 cause an immunodeficiency named 'XMEN syndrome', characterized by CD4 lymphopenia, chronic EBV infection, and EBV-related lymphoproliferative disorders. Patients with XMEN disease have impaired T-cell activation and decreased cytolytic function of natural killer (NK) and CD8 T cells because of decreased expression of the NK stimulatory receptor 'natural-killer group 2, member D' (NKG2D). Patients may have defective specific antibody responses secondary to T cell dysfunction, but B cells have not been shown to be directly affected by mutations in MAGT1. XMEN disease has revealed a novel role for free intracellular magnesium in the immune system. Further understanding of the MAGT1 signaling pathway may lead to new diagnostic and therapeutic approaches.

Induction and Subversion of Human Protective Immunity: Contrasting Influenza and Respiratory Syncytial Virus

Directory of Open Access Journals (Sweden)

Stephanie Ascough

2018-03-01

Full Text Available Respiratory syncytial virus (RSV and influenza are among the most important causes of severe respiratory disease worldwide. Despite the clinical need, barriers to developing reliably effective vaccines against these viruses have remained firmly in place for decades. Overcoming these hurdles requires better understanding of human immunity and the strategies by which these pathogens evade it. Although superficially similar, the virology and host response to RSV and influenza are strikingly distinct. Influenza induces robust strain-specific immunity following natural infection, although protection by current vaccines is short-lived. In contrast, even strain-specific protection is incomplete after RSV and there are currently no licensed RSV vaccines. Although animal models have been critical for developing a fundamental understanding of antiviral immunity, extrapolating to human disease has been problematic. It is only with recent translational advances (such as controlled human infection models and high-dimensional technologies that the mechanisms responsible for differences in protection against RSV compared to influenza have begun to be elucidated in the human context. Influenza infection elicits high-affinity IgA in the respiratory tract and virus-specific IgG, which correlates with protection. Long-lived influenza-specific T cells have also been shown to ameliorate disease. This robust immunity promotes rapid emergence of antigenic variants leading to immune escape. RSV differs markedly, as reinfection with similar strains occurs despite natural infection inducing high levels of antibody against conserved antigens. The immunomodulatory mechanisms of RSV are thus highly effective in inhibiting long-term protection, with disturbance of type I interferon signaling, antigen presentation and chemokine-induced inflammation possibly all contributing. These lead to widespread effects on adaptive immunity with impaired B cell memory and reduced T cell

Induction and Subversion of Human Protective Immunity: Contrasting Influenza and Respiratory Syncytial Virus

Science.gov (United States)

Ascough, Stephanie; Paterson, Suzanna; Chiu, Christopher

2018-01-01

Respiratory syncytial virus (RSV) and influenza are among the most important causes of severe respiratory disease worldwide. Despite the clinical need, barriers to developing reliably effective vaccines against these viruses have remained firmly in place for decades. Overcoming these hurdles requires better understanding of human immunity and the strategies by which these pathogens evade it. Although superficially similar, the virology and host response to RSV and influenza are strikingly distinct. Influenza induces robust strain-specific immunity following natural infection, although protection by current vaccines is short-lived. In contrast, even strain-specific protection is incomplete after RSV and there are currently no licensed RSV vaccines. Although animal models have been critical for developing a fundamental understanding of antiviral immunity, extrapolating to human disease has been problematic. It is only with recent translational advances (such as controlled human infection models and high-dimensional technologies) that the mechanisms responsible for differences in protection against RSV compared to influenza have begun to be elucidated in the human context. Influenza infection elicits high-affinity IgA in the respiratory tract and virus-specific IgG, which correlates with protection. Long-lived influenza-specific T cells have also been shown to ameliorate disease. This robust immunity promotes rapid emergence of antigenic variants leading to immune escape. RSV differs markedly, as reinfection with similar strains occurs despite natural infection inducing high levels of antibody against conserved antigens. The immunomodulatory mechanisms of RSV are thus highly effective in inhibiting long-term protection, with disturbance of type I interferon signaling, antigen presentation and chemokine-induced inflammation possibly all contributing. These lead to widespread effects on adaptive immunity with impaired B cell memory and reduced T cell generation and

Systems Biology of the Immune Response to Live and Inactivated Dengue Virus Vaccines

Science.gov (United States)

2017-09-01

AWARD NUMBER: W81XWH-16-2-0031 TITLE: Systems Biology of the Immune Response to Live and Inactivated Dengue Virus Vaccines PRINCIPAL...SUBTITLE 5a. CONTRACT NUMBER Systems Biology of the Immune Response to Live and Inactivated Dengue Virus Vaccines 5b. GRANT NUMBER W81XWH-16-2-0031 5c...adaptive (T and B cell) responses will be measured using molecular and cellular approaches and the data analyzed using a systems biology approach

Host Innate Immunity against Hepatitis E Virus and Viral Evasion Mechanisms.

Science.gov (United States)

Kang, Sangmin; Myoung, Jinjong

2017-10-28

Hepatitis E virus (HEV) infections cause epidemic or sporadic acute hepatitis, which are mostly self-limiting. However, viral infection in immunocompromised patients and pregnant women may result in serious consequences, such as chronic hepatitis and liver damage, mortality of the latter of which reaches up to 20-30%. Type I interferon (IFN)-induced antiviral immunity is known to be the first-line defense against virus infection. Upon HEV infection in the cell, the virus genome is recognized by pathogen recognition receptors, leading to rapid activation of intracellular signaling cascades. Expression of type I IFN triggers induction of a barrage of IFN-stimulated genes, helping the cells cope with viral infection. Interestingly, some of the HEV-encoded genes seem to be involved in disrupting signaling cascades for antiviral immune responses, and thus crippling cytokine/chemokine production. Antagonistic mechanisms of type I IFN responses by HEV have only recently begun to emerge, and in this review, we summarize known HEV evasion strategies and compare them with those of other hepatitis viruses.

Plasmid DNA initiates replication of yellow fever vaccine in vitro and elicits virus-specific immune response in mice

International Nuclear Information System (INIS)

Tretyakova, Irina; Nickols, Brian; Hidajat, Rachmat; Jokinen, Jenny; Lukashevich, Igor S.; Pushko, Peter

2014-01-01

Yellow fever (YF) causes an acute hemorrhagic fever disease in tropical Africa and Latin America. To develop a novel experimental YF vaccine, we applied iDNA infectious clone technology. The iDNA represents plasmid that encodes the full-length RNA genome of 17D vaccine downstream from a cytomegalovirus (CMV) promoter. The vaccine was designed to transcribe the full-length viral RNA and to launch 17D vaccine virus in vitro and in vivo. Transfection with 10 ng of iDNA plasmid was sufficient to start replication of vaccine virus in vitro. Safety of the parental 17D and iDNA-derived 17D viruses was confirmed in AG129 mice deficient in receptors for IFN-α/β/γ. Finally, direct vaccination of BALB/c mice with a single 20 μg dose of iDNA plasmid resulted in seroconversion and elicitation of virus-specific neutralizing antibodies in animals. We conclude that iDNA immunization approach combines characteristics of DNA and attenuated vaccines and represents a promising vaccination strategy for YF. - Highlights: • The iDNA ® platform combines advantages of DNA and live attenuated vaccines. • Yellow fever (YF) 17D vaccine was launched from iDNA plasmid in vitro and in vivo. • Safety of iDNA-generated 17D virus was confirmed in AG129 mice. • BALB/c mice seroconverted after a single-dose vaccination with iDNA. • YF virus-neutralizing response was elicited in iDNA-vaccinated mice

Plasmid DNA initiates replication of yellow fever vaccine in vitro and elicits virus-specific immune response in mice

Energy Technology Data Exchange (ETDEWEB)

Tretyakova, Irina; Nickols, Brian; Hidajat, Rachmat [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States); Jokinen, Jenny; Lukashevich, Igor S. [Department of Pharmacology and Toxicology, School of Medicine, Center for Predictive Medicine and Emerging Infectious Diseases, University of Louisville, Louisville, KY (United States); Pushko, Peter, E-mail: ppushko@medigen-usa.com [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States)

2014-11-15

Yellow fever (YF) causes an acute hemorrhagic fever disease in tropical Africa and Latin America. To develop a novel experimental YF vaccine, we applied iDNA infectious clone technology. The iDNA represents plasmid that encodes the full-length RNA genome of 17D vaccine downstream from a cytomegalovirus (CMV) promoter. The vaccine was designed to transcribe the full-length viral RNA and to launch 17D vaccine virus in vitro and in vivo. Transfection with 10 ng of iDNA plasmid was sufficient to start replication of vaccine virus in vitro. Safety of the parental 17D and iDNA-derived 17D viruses was confirmed in AG129 mice deficient in receptors for IFN-α/β/γ. Finally, direct vaccination of BALB/c mice with a single 20 μg dose of iDNA plasmid resulted in seroconversion and elicitation of virus-specific neutralizing antibodies in animals. We conclude that iDNA immunization approach combines characteristics of DNA and attenuated vaccines and represents a promising vaccination strategy for YF. - Highlights: • The iDNA{sup ®} platform combines advantages of DNA and live attenuated vaccines. • Yellow fever (YF) 17D vaccine was launched from iDNA plasmid in vitro and in vivo. • Safety of iDNA-generated 17D virus was confirmed in AG129 mice. • BALB/c mice seroconverted after a single-dose vaccination with iDNA. • YF virus-neutralizing response was elicited in iDNA-vaccinated mice.

Human immunodeficiency virus-like particles activate multiple types of immune cells

International Nuclear Information System (INIS)

Sailaja, Gangadhara; Skountzou, Ioanna; Quan, Fu-Shi; Compans, Richard W.; Kang, Sang-Moo

2007-01-01

The rapid spread of human immunodeficiency virus (HIV) worldwide makes it a high priority to develop an effective vaccine. Since live attenuated or inactivated HIV is not likely to be approved as a vaccine due to safety concerns, HIV virus like particles (VLPs) offer an attractive alternative because they are safe due to the lack of a viral genome. Although HIV VLPs have been shown to induce humoral and cellular immune responses, it is important to understand the mechanisms by which they induce such responses and to improve their immunogenicity. We generated HIV VLPs, and VLPs containing Flt3 ligand (FL), a dendritic cell growth factor, to target VLPs to dendritic cells, and investigated the roles of these VLPs in the initiation of adaptive immune responses in vitro and in vivo. We found that HIV-1 VLPs induced maturation of dendritic cells and monocyte/macrophage populations in vitro and in vivo, with enhanced expression of maturation markers and cytokines. Dendritic cells pulsed with VLPs induced activation of splenocytes resulting in increased production of cytokines. VLPs containing FL were found to increase dendritic cells and monocyte/macrophage populations in the spleen when administered to mice. Administration of VLPs induced acute activation of multiple types of cells including T and B cells as indicated by enhanced expression of the early activation marker CD69 and down-regulation of the homing receptor CD62L. VLPs containing FL were an effective form of antigen in activating immune cells via dendritic cells, and immunization with HIV VLPs containing FL resulted in enhanced T helper type 2-like immune responses

Enhancing virus-specific immunity in vivo by combining therapeutic vaccination and PD-L1 blockade in chronic hepadnaviral infection.

Directory of Open Access Journals (Sweden)

Jia Liu

2014-01-01

Full Text Available Hepatitis B virus (HBV persistence is facilitated by exhaustion of CD8 T cells that express the inhibitory receptor programmed cell death-1 (PD-1. Improvement of the HBV-specific T cell function has been obtained in vitro by inhibiting the PD-1/PD-ligand 1 (PD-L1 interaction. In this study, we examined whether in vivo blockade of the PD-1 pathway enhances virus-specific T cell immunity and leads to the resolution of chronic hepadnaviral infection in the woodchuck model. The woodchuck PD-1 was first cloned, characterized, and its expression patterns on T cells from woodchucks with acute or chronic woodchuck hepatitis virus (WHV infection were investigated. Woodchucks chronically infected with WHV received a combination therapy with nucleoside analogue entecavir (ETV, therapeutic DNA vaccination and woodchuck PD-L1 antibody treatment. The gain of T cell function and the suppression of WHV replication by this therapy were evaluated. We could show that PD-1 expression on CD8 T cells was correlated with WHV viral loads during WHV infection. ETV treatment significantly decreased PD-1 expression on CD8 T cells in chronic carriers. In vivo blockade of PD-1/PD-L1 pathway on CD8 T cells, in combination with ETV treatment and DNA vaccination, potently enhanced the function of virus-specific T cells. Moreover, the combination therapy potently suppressed WHV replication, leading to sustained immunological control of viral infection, anti-WHs antibody development and complete viral clearance in some woodchucks. Our results provide a new approach to improve T cell function in chronic hepatitis B infection, which may be used to design new immunotherapeutic strategies in patients.

New Orf virus (Parapoxvirus) recombinant expressing H5 hemagglutinin protects mice against H5N1 and H1N1 influenza A virus.

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Rohde, Jörg; Amann, Ralf; Rziha, Hanns-Joachim

2013-01-01

Previously we demonstrated the versatile utility of the Parapoxvirus Orf virus (ORFV) as a vector platform for the development of potent recombinant vaccines. In this study we present the generation of new ORFV recombinants expressing the hemagglutinin (HA) or nucleoprotein (NP) of the highly pathogenic avian influenza virus (HPAIV) H5N1. Correct foreign gene expression was examined in vitro by immunofluorescence, Western blotting and flow cytometry. The protective potential of both recombinants was evaluated in the mouse challenge model. Despite adequate expression of NP, the recombinant D1701-V-NPh5 completely failed to protect mice from lethal challenge. However, the H5 HA-expressing recombinant D1701-V-HAh5n mediated solid protection in a dose-dependent manner. Two intramuscular (i.m.) injections of the HA-expressing recombinant protected all animals from lethal HPAIV infection without loss of body weight. Notably, the immunized mice resisted cross-clade H5N1 and heterologous H1N1 (strain PR8) influenza virus challenge. In vivo antibody-mediated depletion of CD4-positive and/or CD8-posititve T-cell subpopulations during immunization and/or challenge infection implicated the relevance of CD4-positive T-cells for induction of protective immunity by D1701-V-HAh5n, whereas the absence of CD8-positive T-cells did not significantly influence protection. In summary, this study validates the potential of the ORFV vectored vaccines also to combat HPAIV.

New Orf virus (Parapoxvirus recombinant expressing H5 hemagglutinin protects mice against H5N1 and H1N1 influenza A virus.

Directory of Open Access Journals (Sweden)

Jörg Rohde

Full Text Available Previously we demonstrated the versatile utility of the Parapoxvirus Orf virus (ORFV as a vector platform for the development of potent recombinant vaccines. In this study we present the generation of new ORFV recombinants expressing the hemagglutinin (HA or nucleoprotein (NP of the highly pathogenic avian influenza virus (HPAIV H5N1. Correct foreign gene expression was examined in vitro by immunofluorescence, Western blotting and flow cytometry. The protective potential of both recombinants was evaluated in the mouse challenge model. Despite adequate expression of NP, the recombinant D1701-V-NPh5 completely failed to protect mice from lethal challenge. However, the H5 HA-expressing recombinant D1701-V-HAh5n mediated solid protection in a dose-dependent manner. Two intramuscular (i.m. injections of the HA-expressing recombinant protected all animals from lethal HPAIV infection without loss of body weight. Notably, the immunized mice resisted cross-clade H5N1 and heterologous H1N1 (strain PR8 influenza virus challenge. In vivo antibody-mediated depletion of CD4-positive and/or CD8-posititve T-cell subpopulations during immunization and/or challenge infection implicated the relevance of CD4-positive T-cells for induction of protective immunity by D1701-V-HAh5n, whereas the absence of CD8-positive T-cells did not significantly influence protection. In summary, this study validates the potential of the ORFV vectored vaccines also to combat HPAIV.

Immune regulation in chronic hepatitis C virus infection

DEFF Research Database (Denmark)

Hartling, Hans Jakob; Ballegaard, Vibe Cecilie; Nielsen, Nick Schou

2016-01-01

The immunological result of infection with Hepatitis C virus (HCV) depends on the delicate balance between a vigorous immune response that may clear the infection, but with a risk of unspecific inflammation and, or a less inflammatory response that leads to chronic infection. In general, exhaustion...... and impairment of cytotoxic function of HCV-specific T cells and NK cells are found in patients with chronic HCV infection. In contrast, an increase in immune regulatory functions is found primarily in form of increased IL-10 production possibly due to increased level and function of anti-inflammatory Tregs...

Genetic Characterization of Influenza A (H1N1) Pandemic 2009 Virus Isolates from Mumbai.

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Gohil, Devanshi; Kothari, Sweta; Shinde, Pramod; Meharunkar, Rhuta; Warke, Rajas; Chowdhary, Abhay; Deshmukh, Ranjana

2017-08-01

Pandemic influenza A (H1N1) 2009 virus was first detected in India in May 2009 which subsequently became endemic in many parts of the country. Influenza A viruses have the ability to evade the immune response through its ability of antigenic variations. The study aims to characterize influenza A (H1N1) pdm 09 viruses circulating in Mumbai during the pandemic and post-pandemic period. Nasopharyngeal swabs positive for influenza A (H1N1) pdm 09 viruses were inoculated on Madin-Darby canine kidney cell line for virus isolation. Molecular and phylogenetic analysis of influenza A (H1N1) pdm 09 isolates was conducted to understand the evolution and genetic diversity of the strains. Nucleotide and amino acid sequences of the HA gene of Mumbai isolates when compared to A/California/07/2009-vaccine strain revealed 14 specific amino acid differences located at the antigenic sites. Amino acid variations in HA and NA gene resulted in changes in the N-linked glycosylation motif which may lead to immune evasion. Phylogenetic analysis of the isolates revealed their evolutionary position with vaccine strain A/California/07/2009 but had undergone changes gradually. The findings in the present study confirm genetic variability of influenza viruses and highlight the importance of continuous surveillance during influenza outbreaks.

Protein energy malnutrition decreases immunity and increases susceptibility to influenza infection in mice.

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Taylor, Andrew K; Cao, Weiping; Vora, Keyur P; De La Cruz, Juan; Shieh, Wun-Ju; Zaki, Sherif R; Katz, Jacqueline M; Sambhara, Suryaprakash; Gangappa, Shivaprakash

2013-02-01

Protein energy malnutrition (PEM), a common cause of secondary immune deficiency in children, is associated with an increased risk of infections. Very few studies have addressed the relevance of PEM as a risk factor for influenza. We investigated the influence of PEM on susceptibility to, and immune responses following, influenza virus infection using isocaloric diets providing either adequate protein (AP; 18%) or very low protein (VLP; 2%) in a mouse model. We found that mice maintained on the VLP diet, when compared to mice fed with the AP diet, exhibited more severe disease following influenza infection based on virus persistence, trafficking of inflammatory cell types to the lung tissue, and virus-induced mortality. Furthermore, groups of mice maintained on the VLP diet showed significantly lower virus-specific antibody response and a reduction in influenza nuclear protein-specific CD8(+) T cells compared with mice fed on the AP diet. Importantly, switching diets for the group maintained on the VLP diet to the AP diet improved virus clearance, as well as protective immunity to viral challenge. Our results highlight the impact of protein energy on immunity to influenza infection and suggest that balanced protein energy replenishment may be one strategy to boost immunity against influenza viral infections.

Vaccination with dengue virus-like particles induces humoral and cellular immune responses in mice

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Zhang Quanfu

2011-06-01

Full Text Available Abstract Background The incidence of dengue, an infectious disease caused by dengue virus (DENV, has dramatically increased around the world in recent decades and is becoming a severe public health threat. However, there is currently no specific treatment for dengue fever, and licensed vaccine against dengue is not available. Vaccination with virus-like particles (VLPs has shown considerable promise for many viral diseases, but the effect of DENV VLPs to induce specific immune responses has not been adequately investigated. Results By optimizing the expression plasmids, recombinant VLPs of four antigenically different DENV serotypes DENV1-4 were successfully produced in 293T cells. The vaccination effect of dengue VLPs in mice showed that monovalent VLPs of each serotype stimulated specific IgG responses and potent neutralizing antibodies against homotypic virus. Tetravalent VLPs efficiently enhanced specific IgG and neutralizing antibodies against all four serotypes of DENV. Moreover, vaccination with monovalent or tetravalent VLPs resulted in the induction of specific cytotoxic T cell responses. Conclusions Mammalian cell expressed dengue VLPs are capable to induce VLP-specific humoral and cellular immune responses in mice, and being a promising subunit vaccine candidate for prevention of dengue virus infection.

Immunization of mice with the nef gene from Human Immunodeficiency Virus type 1: Study of immunological memory and long-term toxicology

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Engström Gunnel

2007-07-01

Full Text Available Abstract Background The human immunodeficiency virus type 1 (HIV-1 regulatory protein, Nef, is an attractive vaccine target because it is involved in viral pathogenesis, is expressed early in the viral life cycle and harbors many T and B cell epitopes. Several clinical trials include gene-based vaccines encoding this protein. However, Nef has been shown to transform certain cell types in vitro. Based on these findings we performed a long-term toxicity and immunogenicity study of Nef, encoded either by Modified Vaccinia virus Ankara or by plasmid DNA. BALB/c mice were primed twice with either DNA or MVA encoding Nef and received a homologous or heterologous boost ten months later. In the meantime, the Nef-specific immune responses were monitored and at the time of sacrifice an extensive toxicological evaluation was performed, where presence of tumors and other pathological changes were assessed. Results The toxicological evaluation showed that immunization with MVAnef is safe and does not cause cellular transformation or other toxicity in somatic organs. Both DNAnef and MVAnef immunized animals developed potent Nef-specific cellular responses that declined to undetectable levels over time, and could readily be boosted after almost one year. This is of particular interest since it shows that plasmid DNA vaccine can also be used as a potent late booster of primed immune responses. We observed qualitative differences between the T cell responses induced by the two different vectors: DNA-encoded nef induced long-lasting CD8+ T cell memory responses, whereas MVA-encoded nef induced CD4+ T cell memory responses. In terms of the humoral immune responses, we show that two injections of MVAnef induce significant anti-Nef titers, while repeated injections of DNAnef do not. A single boost with MVAnef could enhance the antibody response following DNAnef prime to the same level as that observed in animals immunized repeatedly with MVAnef. We also demonstrate

Aryl hydrocarbon receptor signaling modulates antiviral immune responses: ligand metabolism rather than chemical source is the stronger predictor of outcome.

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Boule, Lisbeth A; Burke, Catherine G; Jin, Guang-Bi; Lawrence, B Paige

2018-01-29

The aryl hydrocarbon receptor (AHR) offers a compelling target to modulate the immune system. AHR agonists alter adaptive immune responses, but the consequences differ across studies. We report here the comparison of four agents representing different sources of AHR ligands in mice infected with influenza A virus (IAV): TCDD, prototype exogenous AHR agonist; PCB126, pollutant with documented human exposure; ITE, novel pharmaceutical; and FICZ, degradation product of tryptophan. All four compounds diminished virus-specific IgM levels and increased the proportion of regulatory T cells. TCDD, PCB126 and ITE, but not FICZ, reduced virus-specific IgG levels and CD8 + T cell responses. Similarly, ITE, PCB126, and TCDD reduced Th1 and Tfh cells, whereas FICZ increased their frequency. In Cyp1a1-deficient mice, all compounds, including FICZ, reduced the response to IAV. Conditional Ahr knockout mice revealed that all four compounds require AHR within hematopoietic cells. Thus, differences in the immune response to IAV likely reflect variances in quality, magnitude, and duration of AHR signaling. This indicates that binding affinity and metabolism may be stronger predictors of immune effects than a compound's source of origin, and that harnessing AHR will require finding a balance between dampening immune-mediated pathologies and maintaining sufficient host defenses against infection.

Improved Insulin Sensitivity despite Increased Visceral Adiposity in Mice Deficient for the Immune Cell Transcription Factor T-bet

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Stolarczyk, Emilie; Vong, Chi Teng; Perucha, Esperanza; Jackson, Ian; Cawthorne, Michael A.; Wargent, Edward T.; Powell, Nick; Canavan, James B.; Lord, Graham M.; Howard, Jane K.

2013-01-01

Summary Low-grade inflammation in fat is associated with insulin resistance, although the mechanisms are unclear. We report that mice deficient in the immune cell transcription factor T-bet have lower energy expenditure and increased visceral fat compared with wild-type mice, yet paradoxically are more insulin sensitive. This striking phenotype, present in young T-bet−/− mice, persisted with high-fat diet and increasing host age and was associated with altered immune cell numbers and cytokine secretion specifically in visceral adipose tissue. However, the favorable metabolic phenotype observed in T-bet-deficient hosts was lost in T-bet−/− mice also lacking adaptive immunity (T-bet−/−xRag2−/−), demonstrating that T-bet expression in the adaptive rather than the innate immune system impacts host glucose homeostasis. Indeed, adoptive transfer of T-bet-deficient, but not wild-type, CD4+ T cells to Rag2−/− mice improved insulin sensitivity. Our results reveal a role for T-bet in metabolic physiology and obesity-associated insulin resistance. PMID:23562076

Experimental and Field Results Regarding Immunity Induced by a Recombinant Turkey Herpesvirus H5 Vector Vaccine Against H5N1 and Other H5 Highly Pathogenic Avian Influenza Virus Challenges.

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Gardin, Yannick; Palya, Vilmos; Dorsey, Kristi Moore; El-Attrache, John; Bonfante, Francesco; Wit, Sjaak de; Kapczynski, Darrell; Kilany, Walid Hamdy; Rauw, Fabienne; Steensels, Mieke; Soejoedono, Retno D

2016-05-01

Vaccination against H5N1 highly pathogenic avian influenza (AI) virus (HPAIV) is one of the possible complementary means available for affected countries to control AI when the disease has become, or with a high risk of becoming, endemic. Efficacy of the vaccination against AI relies essentially, but not exclusively, on the capacity of the vaccine to induce immunity against the targeted virus (which is prone to undergo antigenic variations), as well as its capacity to overcome interference with maternal immunity transmitted by immunized breeding hens to their progeny. This property of the vaccine is a prerequisite for its administration at the hatchery, which assures higher and more reliable vaccine coverage of the populations than vaccination at the farm. A recombinant vector vaccine (Vectormune® AI), based on turkey herpesvirus expressing the hemagglutinin gene of an H5N1 HPAIV as an insert, has been used in several experiments conducted in different research laboratories, as well as in controlled field trials. The results have demonstrated a high degree of homologous and cross protection against different genetic clades of the H5N1 HPAIV. Furthermore, vaccine-induced immunity was not impaired by the presence of passive immunity, but on the contrary, cumulated with it for improved early protection. The demonstrated levels of protection against the different challenge viruses exhibited variations in terms of postchallenge mortality, as well as challenge virus shedding. The data presented here highlight the advantages of this vaccine as a useful and reliable tool to complement biosecurity and sanitary policies for better controlling the disease due to HPAIV of H5 subtypes, when the vaccination is applied as a control measure.

Engineering Plant Immunity: Using CRISPR/Cas9 to Generate Virus Resistance

KAUST Repository

Zaidi, Syed Shan-e-Ali

2016-11-08

Plant viruses infect many economically important crops, including wheat, cotton, maize, cassava, and other vegetables. These viruses pose a serious threat to agriculture worldwide, as decreases in cropland area per capita may cause production to fall short of that required to feed the increasing world population. Under these circumstances, conventional strategies can fail to control rapidly evolving and emerging plant viruses. Genome-engineering strategies have recently emerged as promising tools to introduce desirable traits in many eukaryotic species, including plants. Among these genome engineering technologies, the CRISPR (clustered regularly interspaced palindromic repeats)/CRISPR-associated 9 (CRISPR/Cas9) system has received special interest because of its simplicity, efficiency, and reproducibility. Recent studies have used CRISPR/Cas9 to engineer virus resistance in plants, either by directly targeting and cleaving the viral genome, or by modifying the host plant genome to introduce viral immunity. Here, we briefly describe the biology of the CRISPR/Cas9 system and plant viruses, and how different genome engineering technologies have been used to target these viruses. We further describe the main findings from recent studies of CRISPR/Cas9-mediated viral interference and discuss how these findings can be applied to improve global agriculture. We conclude by pinpointing the gaps in our knowledge and the outstanding questions regarding CRISPR/Cas9-mediated viral immunity.

Engineering Plant Immunity: Using CRISPR/Cas9 to Generate Virus Resistance

KAUST Repository

Zaidi, Syed Shan-e-Ali; Tashkandi, Manal; Mansoor, Shahid; Mahfouz, Magdy M.

2016-01-01

Plant viruses infect many economically important crops, including wheat, cotton, maize, cassava, and other vegetables. These viruses pose a serious threat to agriculture worldwide, as decreases in cropland area per capita may cause production to fall short of that required to feed the increasing world population. Under these circumstances, conventional strategies can fail to control rapidly evolving and emerging plant viruses. Genome-engineering strategies have recently emerged as promising tools to introduce desirable traits in many eukaryotic species, including plants. Among these genome engineering technologies, the CRISPR (clustered regularly interspaced palindromic repeats)/CRISPR-associated 9 (CRISPR/Cas9) system has received special interest because of its simplicity, efficiency, and reproducibility. Recent studies have used CRISPR/Cas9 to engineer virus resistance in plants, either by directly targeting and cleaving the viral genome, or by modifying the host plant genome to introduce viral immunity. Here, we briefly describe the biology of the CRISPR/Cas9 system and plant viruses, and how different genome engineering technologies have been used to target these viruses. We further describe the main findings from recent studies of CRISPR/Cas9-mediated viral interference and discuss how these findings can be applied to improve global agriculture. We conclude by pinpointing the gaps in our knowledge and the outstanding questions regarding CRISPR/Cas9-mediated viral immunity.

Immunization against Genital Herpes with a Vaccine Virus That has Defects in Productive and Latent Infection

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da Costa, Xavier J.; Jones, Cheryl A.; Knipe, David M.

1999-06-01

An effective vaccine for genital herpes has been difficult to achieve because of the limited efficacy of subunit vaccines and the safety concerns about live viruses. As an alternative approach, mutant herpes simplex virus strains that are replication-defective can induce protective immunity. To increase the level of safety and to prove that replication was not needed for immunization, we constructed a mutant herpes simplex virus 2 strain containing two deletion mutations, each of which eliminated viral replication. The double-mutant virus induces protective immunity that can reduce acute viral shedding and latent infection in a mouse genital model, but importantly, the double-mutant virus shows a phenotypic defect in latent infection. This herpes vaccine strain, which is immunogenic but has defects in both productive and latent infection, provides a paradigm for the design of vaccines and vaccine vectors for other sexually transmitted diseases, such as AIDS.

Founder virus population related to route of virus transmission: a determinant of intrahost human immunodeficiency virus type 1 evolution?

NARCIS (Netherlands)

Lukashov, V. V.; Goudsmit, J.

1997-01-01

We and others have shown that in individual human immunodeficiency virus type 1 (HIV-1) infection, the adaptive evolution of HIV-1 is influenced by host immune competence. In this study, we tested the hypothesis that in addition to selective forces operating within the host, transmission bottlenecks

Enhancement of mucosal immune responses by chimeric influenza HA/SHIV virus-like particles

International Nuclear Information System (INIS)

Guo Lizheng; Lu Xiaoyan; Kang, S.-M.; Chen Changyi; Compans, Richard W.; Yao Qizhi

2003-01-01

To enhance mucosal immune responses using simian/human immunodeficiency virus-like particles (SHIV VLPs), we have produced novel phenotypically mixed chimeric influenza HA/SHIV VLPs and used them to immunize C57BL/6J mice intranasally. Antibody and cytotoxic T-cell (CTL) responses as well as cytokine production in both systemic and mucosal sites were compared after immunization with SHIV VLPs or chimeric HA/SHIV VLPs. By using enzyme-linked immunosorbent assay (ELISA), the levels of serum IgG and mucosal IgA to the HIV envelope protein (Env) were found to be highest in the group immunized with chimeric HA/SHIV VLPs. Furthermore, the highest titer of serum neutralizing antibody against HIV Env was found with the group immunized with chimeric HA/SHIV VLPs. Analysis of the IgG1/IgG2a ratio indicated that a T H 1-oriented immune response resulted from these VLP immunizations. HA/SHIV VLP-immunized mice also showed significantly higher CTL responses than those observed in SHIV VLP-immunized mice. Moreover, a MHC class I restricted T-cell activation ELISPOT assay showed a mixed type of T H 1/T H 2 cytokines in the HA/SHIV VLP-immunized mice, indicating that the chimeric VLPs can enhance both humoral and cellular immune responses to the HIV Env protein at multiple mucosal and systemic sites. The results indicate that incorporation of influenza HA into heterotypic VLPs may be highly effective for targeting vaccines to mucosal surfaces

Quadruple burden of HIV/AIDS, tuberculosis, chronic intestinal parasitoses, and multiple micronutrient deficiency in ethiopia: a summary of available findings.

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Amare, Bemnet; Moges, Beyene; Mulu, Andargachew; Yifru, Sisay; Kassu, Afework

2015-01-01

Human immunodeficiency virus (HIV), tuberculosis (TB), and helminthic infections are among the commonest public health problems in the sub-Saharan African countries like Ethiopia. Multiple micronutrient deficiencies also known as the "hidden hunger" are common in people living in these countries either playing a role in their pathogenesis or as consequences. This results in a vicious cycle of multiple micronutrient deficiencies and infection/disease progression. As infection is profoundly associated with nutritional status resulting from decreased nutrient intake, decreased nutrient absorption, and nutrient losses, micronutrient deficiencies affect immune system and impact infection and diseases progression. As a result, micronutrients, immunity, and infection are interrelated. The goal of this review is therefore to provide a summary of available findings regarding the "quadruple burden trouble" of HIV, TB, intestinal parasitic infections, and multiple micronutrient deficiencies to describe immune-modulating effects related to disorders.

Protection against H5N1 Highly Pathogenic Avian and Pandemic (H1N1) 2009 Influenza Virus Infection in Cynomolgus Monkeys by an Inactivated H5N1 Whole Particle Vaccine

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Nakayama, Misako; Shichinohe, Shintaro; Itoh, Yasushi; Ishigaki, Hirohito; Kitano, Mitsutaka; Arikata, Masahiko; Pham, Van Loi; Ishida, Hideaki; Kitagawa, Naoko; Okamatsu, Masatoshi; Sakoda, Yoshihiro; Ichikawa, Takaya; Tsuchiya, Hideaki; Nakamura, Shinichiro; Le, Quynh Mai; Ito, Mutsumi; Kawaoka, Yoshihiro; Kida, Hiroshi; Ogasawara, Kazumasa

2013-01-01

H5N1 highly pathogenic avian influenza virus (HPAIV) infection has been reported in poultry and humans with expanding clade designations. Therefore, a vaccine that induces immunity against a broad spectrum of H5N1 viruses is preferable for pandemic preparedness. We established a second H5N1 vaccine candidate, A/duck/Hokkaido/Vac-3/2007 (Vac-3), in our virus library and examined the efficacy of inactivated whole particles of this strain against two clades of H5N1 HPAIV strains that caused severe morbidity in cynomolgus macaques. Virus propagation in vaccinated macaques infected with either of the H5N1 HPAIV strains was prevented compared with that in unvaccinated macaques. This vaccine also prevented propagation of a pandemic (H1N1) 2009 virus in macaques. In the vaccinated macaques, neutralization activity, which was mainly shown by anti-hemagglutinin antibody, against H5N1 HPAIVs in plasma was detected, but that against H1N1 virus was not detected. However, neuraminidase inhibition activity in plasma and T-lymphocyte responses in lymph nodes against H1N1 virus were detected. Therefore, cross-clade and heterosubtypic protective immunity in macaques consisted of humoral and cellular immunity induced by vaccination with Vac-3. PMID:24376571

Protection against H5N1 highly pathogenic avian and pandemic (H1N1 2009 influenza virus infection in cynomolgus monkeys by an inactivated H5N1 whole particle vaccine.

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Misako Nakayama

Full Text Available H5N1 highly pathogenic avian influenza virus (HPAIV infection has been reported in poultry and humans with expanding clade designations. Therefore, a vaccine that induces immunity against a broad spectrum of H5N1 viruses is preferable for pandemic preparedness. We established a second H5N1 vaccine candidate, A/duck/Hokkaido/Vac-3/2007 (Vac-3, in our virus library and examined the efficacy of inactivated whole particles of this strain against two clades of H5N1 HPAIV strains that caused severe morbidity in cynomolgus macaques. Virus propagation in vaccinated macaques infected with either of the H5N1 HPAIV strains was prevented compared with that in unvaccinated macaques. This vaccine also prevented propagation of a pandemic (H1N1 2009 virus in macaques. In the vaccinated macaques, neutralization activity, which was mainly shown by anti-hemagglutinin antibody, against H5N1 HPAIVs in plasma was detected, but that against H1N1 virus was not detected. However, neuraminidase inhibition activity in plasma and T-lymphocyte responses in lymph nodes against H1N1 virus were detected. Therefore, cross-clade and heterosubtypic protective immunity in macaques consisted of humoral and cellular immunity induced by vaccination with Vac-3.

An update: Epstein-Barr virus and immune evasion via microRNA regulation.

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Zuo, Lielian; Yue, Wenxin; Du, Shujuan; Xin, Shuyu; Zhang, Jing; Liu, Lingzhi; Li, Guiyuan; Lu, Jianhong

2017-06-01

Epstein-Barr virus (EBV) is an oncogenic virus that ubiquitously establishes life-long persistence in humans. To ensure its survival and maintain its B cell transformation function, EBV has developed powerful strategies to evade host immune responses. Emerging evidence has shown that microRNAs (miRNAs) are powerful regulators of the maintenance of cellular homeostasis. In this review, we summarize current progress on how EBV utilizes miRNAs for immune evasion. EBV encodes miRNAs targeting both viral and host genes involved in the immune response. The miRNAs are found in two gene clusters, and recent studies have demonstrated that lack of these clusters increases the CD4 + and CD8 + T cell response of infected cells. These reports strongly indicate that EBV miRNAs are critical for immune evasion. In addition, EBV is able to dysregulate the expression of a variety of host miRNAs, which influence multiple immune-related molecules and signaling pathways. The transport via exosomes of EBV-regulated miRNAs and viral proteins contributes to the construction and modification of the inflammatory tumor microenvironment. During EBV immune evasion, viral proteins, immune cells, chemokines, pro-inflammatory cytokines, and pro-apoptosis molecules are involved. Our increasing knowledge of the role of miRNAs in immune evasion will improve the understanding of EBV persistence and help to develop new treatments for EBV-associated cancers and other diseases.

Human immuno-deficiency virus antibody seroprevalence among pregnant women at booking at a university teaching hospital in South-Eastern Nigeria.

Science.gov (United States)

Okeudo, C; Ezem, B U; Ojiyi, E C

2012-01-01

In Africa, human immuno-deficiency virus (HIV) infection continues to be progressively feminized. This has led to an increase in the number of paediatric HIV infections reported due to increased risk of mother-to-child transmission (MTCT) of HIV during pregnancy, labour and breastfeeding. The objective of the study was to determine the HIV positive sero-prevalence at booking among pregnant women at the Imo State University Teaching Hospital, Orlu. A retrospective analysis of the case records of women who booked and were screened for Human Immune-deficiency Virus at the Imo State University Teaching Hospital (IMSUTH), Orlu from 1st March 2008 to 28th February 2010 was done. Data on age, parity, educational status, gestational age at booking, and retroviral status were collected and analysed using spss version 13. Nine hundred and twenty one pregnant women were screened for the presence of HIV 1 & 2 antibodies in their serum. One hundred and six of them were positive, giving a sero-prevalence rate at booking of 11.5%. The highest sero prevalence rate of 45.2% occurred in the age group of 26-30 years. Petty traders contributed 97 (91.5%) of the HIV positive women, while multiparous (para 2-4) women contributed 50% of the positive pregnant women. Only 32 (30.2%) of the HIV positive women booked within the first trimester for antenatal care. Majority 53 (59.4%) of the HIV positive women had secondary education, while those that had no formal education contributed only 6 (5.7%) of the HIV positive women. There was a high HIV seroprevalence at booking among pregnant women at IMSUTH, Orlu. A lot more needs to be done in order to reduce vertical transmission of HIV in our environment.

Immune deficiency vs. immune excess in inflammatory bowel diseases-STAT3 as a rheo-STAT of intestinal homeostasis.

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Leppkes, Moritz; Neurath, Markus F; Herrmann, Martin; Becker, Christoph

2016-01-01

Genome-wide association studies have provided many genetic alterations, conferring susceptibility to multifactorial polygenic diseases, such as inflammatory bowel diseases. Yet, how specific genetic alterations functionally affect intestinal inflammation often remains elusive. It is noteworthy that a large overlap of genes involved in immune deficiencies with those conferring inflammatory bowel disease risk has been noted. This has provided new arguments for the debate on whether inflammatory bowel disease arises from either an excess or a deficiency in the immune system. In this review, we highlight the functional effect of an inflammatory bowel disease-risk allele, which cannot be deduced from genome-wide association studies data alone. As exemplified by the transcription factor signal transducer and activator of transcription 3 (STAT3), we show that a single gene can have a plethora of effects in various cell types of the gut. These effects may individually contribute to the restoration of intestinal homeostasis on the one hand or pave the way for excessive immunopathology on the other, as an inflammatory "rheo-STAT". © Society for Leukocyte Biology.

Enhanced mucosal immune responses induced by a combined candidate mucosal vaccine based on Hepatitis A virus and Hepatitis E virus structural proteins linked to tuftsin.

Science.gov (United States)

Gao, Yan; Su, Qiudong; Yi, Yao; Jia, Zhiyuan; Wang, Hao; Lu, Xuexin; Qiu, Feng; Bi, Shengli

2015-01-01

Hepatitis A virus (HAV) and Hepatitis E virus (HEV) are the most common causes of infectious hepatitis. These viruses are spread largely by the fecal-oral route and lead to clinically important disease in developing countries. To evaluate the potential of targeting hepatitis A and E infection simultaneously, a combined mucosal candidate vaccine was developed with the partial open reading frame 2 (ORF2) sequence (aa 368-607) of HEV (HE-ORF2) and partial virus protein 1 (VP1) sequence (aa 1-198) of HAV (HA-VP1), which included the viral neutralization epitopes. Tuftsin is an immunostimulatory peptide which can enhance the immunogenicity of a protein by targeting it to macrophages and dendritic cells. Here, we developed a novel combined protein vaccine by conjugating tuftsin to HE-ORF2 and HA-VP1 and used synthetic CpG oligodeoxynucleotides (ODNs) as the adjuvant. Subsequent experiments in BALB/c mice demonstrated that tuftsin enhanced the serum-specific IgG and IgA antibodies against HEV and HAV at the intestinal, vaginal and pulmonary interface when delivered intranasally. Moreover, mice from the intranasally immunized tuftsin group (HE-ORF2-tuftsin + HA-VP1-tuftsin + CpG) showed higher levels of IFN-γ-secreting splenocytes (Th1 response) and ratio of CD4+/CD8+ T cells than those of the no-tuftsin group (HE-ORF2 + HA-VP1 + CpG). Thus, the tuftsin group generated stronger humoral and cellular immune responses compared with the no-tuftsin group. Moreover, enhanced responses to the combined protein vaccine were obtained by intranasal immunization compared with intramuscular injection. By integrating HE-ORF2, HA-VP1 and tuftsin in a vaccine, this study validated an important concept for further development of a combined mucosal vaccine against hepatitis A and E infection.

Opportunistic Infections and Complications in Human Immunodeficiency Virus-1-Infected Children: Correlation with immune status

Directory of Open Access Journals (Sweden)

Jaivinder Yadav

2014-10-01

Full Text Available Objectives: The aim of this study was to ascertain the correlation between various opportunistic infections and complications in human immunodeficiency virus (HIV-1-infected children and the immune status of these patients, evaluated by absolute cluster of differentiation 4 (CD4 count and CD4 percentage. Methods: This study was conducted from January 2009 to June 2010 at the Antiretroviral Treatment Centre of the Pt. B.D. Sharma Post Graduate Institute of Medical Sciences, a tertiary care hospital in Rohtak, Haryana, in northern India. A total of 20 HIV-1-infected children aged 4–57 months were studied. Demographic and baseline investigations were performed prior to the start of highly active antiretroviral therapy (HAART. A fixed-dose combination of HAART was given based on the patient’s weight. Baseline investigations were repeated after six months of HAART. Results: There was a significant increase in the patients’ haemoglobin, weight, height and CD4 count after six months of HAART. Significant improvements (P <0.05 were also noted in the patients’ immune status, graded according to the World Health Organization. Conclusion: This study observed that the severity and frequency of opportunistic complications in paediatric patients with HIV-1 increased with a fall in the CD4 count. The treatment of opportunistic infections, along with antiretroviral therapy, may lead to both clinical and immunological recovery as well as a decreased incidence of future opportunistic infections. The CD4 count may give treating physicians an initial idea about the immune status of each child and could also be used as a biological marker of HAART efficacy. Patient compliance must be ensured during HAART as this is a key factor in improving outcomes.

Recombinant in vitro assembled hepatitis C virus core particles induce strong specific immunity enhanced by formulation with an oil-based adjuvant

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NELSON ACOSTA-RIVERO

2009-01-01

Full Text Available In the present work, immunogenicity of recombinant in vitro assembled hepatitis C virus core particles, HCcAg.120-VLPs, either alone or in combination with different adjuvants was evaluated in BALB/c mice. HCcAg.120-VLPs induced high titers of anti-HCcAg.120 antibodies and virus-specific cellular immune responses. Particularly, HCcAg.120-VLPs induced specific delayed type hypersensitivity, and generated a predominant T helper 1 cytokine pro file in immunized mice. In addition, HCcAg.120-VLPs prime splenocytes proliferate in vitro against different HCcAg.120-specific peptides, depending on either the immunization route or the adjuvant used. Remarkably, immunization with HCcAg.120-VLPs/Montanide ISA888 formulation resulted in a significant control of vaccinia virus titer in mice after challenge with a recombinant vaccinia virus expressing HCV core protein, vvCore. Animals immunized with this formulation had a marked increase in the number of IFN-γ producing spleen cells, after stimulation with P815 cells infected with vvCore. These results suggest the use of recombinant HCV core particles as components of therapeutic or preventive vaccine candidates against HCV.

Three-year duration of immunity in dogs following vaccination against canine adenovirus type-1, canine parvovirus, and canine distemper virus.

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Gore, Thomas C; Lakshmanan, Nallakannu; Duncan, Karen L; Coyne, Michael J; Lum, Melissa A; Sterner, Frank J

2005-01-01

A challenge-of-immunity study was conducted to demonstrate immunity in dogs 3 years after their second vaccination with a new multivalent, modified-live vaccine containing canine adenovirus type 2 (CAV-2), canine parvovirus (CPV), and canine distemper virus (CDV). Twenty-three seronegative pups were vaccinated at 7 and 11 weeks of age. Eighteen seronegative pups, randomized into groups of six dogs, served as challenge controls. Dogs were kept in strict isolation for 3 years following the vaccination and then challenged sequentially with virulent canine adenovirus type 1 (CAV-1), CPV, and CDV. For each viral challenge, a separate group of six control dogs was also challenged. Clinical signs of CAV-1, CPV, and CDV infections were prevented in 100% of vaccinated dogs, demonstrating that the multivalent, modified-live test vaccine provided protection against virulent CAV-1, CPV, and CDV challenge in dogs 7 weeks of age or older for a minimum of 3 years following second vaccination.

The innate immunity of guinea pigs against highly pathogenic avian influenza virus infection.

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Zhang, Kun; Xu, Wei Wei; Zhang, Zhaowei; Liu, Jing; Li, Jing; Sun, Lijuan; Sun, Weiyang; Jiao, Peirong; Sang, Xiaoyu; Ren, Zhiguang; Yu, Zhijun; Li, Yuanguo; Feng, Na; Wang, Tiecheng; Wang, Hualei; Yang, Songtao; Zhao, Yongkun; Zhang, Xuemei; Wilker, Peter R; Liu, WenJun; Liao, Ming; Chen, Hualan; Gao, Yuwei; Xia, Xianzhu

2017-05-02

H5N1 avian influenza viruses are a major pandemic concern. In contrast to the highly virulent phenotype of H5N1 in humans and many animal models, guinea pigs do not typically display signs of severe disease in response to H5N1 virus infection. Here, proteomic and transcriptional profiling were applied to identify host factors that account for the observed attenuation of A/Tiger/Harbin/01/2002 (H5N1) virulence in guinea pigs. RIG-I and numerous interferon stimulated genes were among host proteins with altered expression in guinea pig lungs during H5N1 infection. Overexpression of RIG-I or the RIG-I adaptor protein MAVS in guinea pig cell lines inhibited H5N1 replication. Endogenous GBP-1 expression was required for RIG-I mediated inhibition of viral replication upstream of the activity of MAVS. Furthermore, we show that guinea pig complement is involved in viral clearance, the regulation of inflammation, and cellular apoptosis during influenza virus infection of guinea pigs. This work uncovers features of the guinea pig innate immune response to influenza that may render guinea pigs resistant to highly pathogenic influenza viruses.

A replication-deficient rabies virus vaccine expressing Ebola virus glycoprotein is highly attenuated for neurovirulence

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Papaneri, Amy B. [Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, MD 21702 (United States); Wirblich, Christoph [Department of Microbiology and Immunology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Cann, Jennifer A.; Cooper, Kurt [Integrated Research Facility, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick MD, 21702 (United States); Jahrling, Peter B. [Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, MD 21702 (United States); Integrated Research Facility, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick MD, 21702 (United States); Schnell, Matthias J., E-mail: matthias.schnell@jefferson.edu [Department of Microbiology and Immunology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Jefferson Vaccine Center, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Blaney, Joseph E., E-mail: jblaney@niaid.nih.gov [Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, MD 21702 (United States)

2012-12-05

We are developing inactivated and live-attenuated rabies virus (RABV) vaccines expressing Ebola virus (EBOV) glycoprotein for use in humans and endangered wildlife, respectively. Here, we further characterize the pathogenesis of the live-attenuated RABV/EBOV vaccine candidates in mice in an effort to define their growth properties and potential for safety. RABV vaccines expressing GP (RV-GP) or a replication-deficient derivative with a deletion of the RABV G gene (RV{Delta}G-GP) are both avirulent after intracerebral inoculation of adult mice. Furthermore, RV{Delta}G-GP is completely avirulent upon intracerebral inoculation of suckling mice unlike parental RABV vaccine or RV-GP. Analysis of RV{Delta}G-GP in the brain by quantitative PCR, determination of virus titer, and immunohistochemistry indicated greatly restricted virus replication. In summary, our findings indicate that RV-GP retains the attenuation phenotype of the live-attenuated RABV vaccine, and RV{Delta}G-GP would appear to be an even safer alternative for use in wildlife or consideration for human use.

A recombinant canine distemper virus expressing a modified rabies virus glycoprotein induces immune responses in mice.

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Li, Zhili; Wang, Jigui; Yuan, Daoli; Wang, Shuang; Sun, Jiazeng; Yi, Bao; Hou, Qiang; Mao, Yaping; Liu, Weiquan

2015-06-01

Canine distemper virus (CDV) and rabies virus (RV) are two important pathogens of the dog. CDV, a member of the morbillivirus genus, has shown promise as an expression vector. The glycoprotein from RV is a main contributor to protective immunity and capable of eliciting the production of virus-neutralizing antibodies. In this study, we recovered an attenuated strain of canine distemper virus and constructed a recombinant virus, rCDV-RV-G, expressing a modified (R333Q) rabies virus glycoprotein (RV-G) of RV Flury strain LEP. RV-G expression by the recombinant viruses was confirmed. Furthermore, G was proved to be incorporated into the surface of CDV particles. While replication of the recombinant virus was slightly reduced compared with the parental CDV, it stably expressed the RV-G over ten serial passages. Inoculation of mice induced specific neutralizing antibodies against both RV-G and CDV. Therefore, the rCDV-RV-G has the potential as a vaccine that may be used to control rabies virus infection in dogs and other animals.

DNA immunization against experimental genital herpes simplex virus infection.

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Bourne, N; Stanberry, L R; Bernstein, D I; Lew, D

1996-04-01

A nucleic acid vaccine, expressing the gene encoding herpes simplex virus (HSV) type 2 glycoprotein D (gD2) under control of the cytomegalovirus immediate-early gene promoter, was used to immunize guinea pigs against genital HSV-2 infection. The vaccine elicited humoral immune responses comparable to those seen after HSV-2 infection. Immunized animals exhibited protection from primary genital HSV-2 disease with little or no development of vesicular skin lesions and significantly reduced HSV-2 replication in the genital tract. After recovery from primary infection, immunized guinea pigs experienced significantly fewer recurrences and had significantly less HSV-2 genomic DNA detected in the sacral dorsal root ganglia compared with control animals. Thus, immunization reduced the burden of latent infection resulting from intravaginal HSV-2 challenge, and a nucleic acid vaccine expressing the HSV-2 gD2 antigen protected guinea pigs against genital herpes, limiting primary infection and reducing the magnitude of latent infection and the frequency of recurrent disease.

Is immune system-related hypertension associated with ovarian hormone deficiency?

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Sandberg, Kathryn; Ji, Hong; Einstein, Gillian; Au, April; Hay, Meredith

2016-03-01

What is the topic of this review? This review summarizes recent data on the role of ovarian hormones and sex in inflammation-related hypertension. What advances does it highlight? The adaptive immune system has recently been implicated in the development of hypertension in males but not in females. The role of the immune system in the development of hypertension in women and its relationship to ovarian hormone production are highlighted. The immune system is known to contribute to the development of high blood pressure in males. However, the role of the immune system in the development of high blood pressure in females and the role of ovarian hormones has only recently begun to be studied. In animal studies, both the sex of the host and the T cell are critical biological determinants of susceptibility and resistance to hypertension induced by angiotensin II. In women, natural menopause is known to result in significant changes in the expression of genes regulating the immune system. Likewise, in animal models, ovariectomy results in hypertension and an upregulation in T-cell tumour necrosis factor-α-related genes. Oestrogen replacement results in decreases in inflammatory genes in the brain regions involved in blood pressure regulation. Together, these studies suggest that the response of the adaptive immune system to ovarian hormone deficiency is a significant contributor to hypertension in women. © 2015 The Authors. Experimental Physiology © 2015 The Physiological Society.

Resistance and Protective Immunity in Redfish Lake Sockeye Salmon Exposed to M Type Infectious Hematopoietic Necrosis Virus (IHNV)

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Kurath, Gael; Garver, Kyle; Purcell, Maureen K.; LaPatra, Scott E.

2010-01-01

Differential virulence of infectious hematopoietic necrosis virus (IHNV) isolates from the U and M phylogenetic subgroups is clearly evident in the Redfish Lake (RFL) strain of sockeye salmon Oncorhynchus nerka. In these fish, experimental immersion challenges with U isolates cause extremely high mortality and M isolates cause low or no mortality. When survivors of M virus immersion challenges were exposed to a secondary challenge with virulent U type virus they experienced high mortality, indicating that the primary M challenge did not elicit protective immunity. Delivery of a moderate dose (2 × 104 plaque-forming units [PFU]/fish) of virus by intraperitoneal injection challenge did not overcome RFL sockeye salmon resistance to M type IHNV. Injection challenge with a high dose (5 × 106 PFU/fish) of M type virus caused 10% mortality, and in this case survivors did develop protective immunity against a secondary U type virus challenge. Thus, although it is possible for M type IHNV to elicit cross-protective immunity in this disease model, it does not develop after immersion challenge despite entry, transient replication of M virus to low levels, stimulation of innate immune genes, and development of neutralizing antibodies in some fish.

Evaluation of recombinant influenza virus-simian immunodeficiency virus vaccines in macaques.