Memory CD8+ T Cells: Orchestrators and Key Players of Innate Immunity?

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Grégoire Lauvau

2016-09-01

Full Text Available Over the past decades, the dichotomy between innate and adaptive immune responses has largely dominated our understanding of immunology. Upon primary encounter with microbial pathogens, differentiation of adaptive immune cells into functional effectors usually takes several days or even longer, making them contribute to host protection only late during primary infection. However, once generated, antigen-experienced T lymphocytes can persist in the organism and constitute a pool of memory cells that mediate fast and effective protection to a recall infection with the same microbial pathogen. Herein, we challenge this classical paradigm by highlighting the "innate nature" of memory CD8+ T cells. First, within the thymus or in the periphery, naïve CD8+ T cells may acquire phenotypic and functional characteristics of memory CD8+ T cells independently of challenge with foreign antigens. Second, both the "unconventional" and the "conventional" memory cells can rapidly express protective effector functions in response to sets of inflammatory cytokines and chemokines signals, independent of cognate antigen triggering. Third, memory CD8+ T cells can act by orchestrating the recruitment, activation, and licensing of innate cells, leading to broad antimicrobial states. Thus, collectively, memory CD8+ T cells may represent important actors of innate immune defenses.

The Role of Epigenetic Regulation in Transcriptional Memory in the Immune System.

Science.gov (United States)

Woodworth, A M; Holloway, A F

The immune system is exquisitely poised to identify, respond to, and eradicate pathogens from the body, as well as to produce a more rapid and augmented response to a subsequent encounter with the pathogen. These cellular responses rely on the highly coordinated and rapid activation of gene expression programs as well as the ability of the cell to retain a memory of the initial gene response. It is clear that chromatin structure and epigenetic mechanisms play a crucial role in determining these gene responses, and in fact the immune system has proved an instructive model for investigating the multifaceted mechanisms through which the chromatin landscape contributes to gene expression programs. These mechanisms include modifications to the DNA and histone proteins, the positioning, composition, and remodeling of nucleosomes, as well as the formation of higher-order chromatin structures. Moreover, it is now apparent that epigenetic mechanisms also provide an instrument by which cells can retain memory of the initial transcriptional response, "priming" the genome so that it can respond more quickly to subsequent exposure to the signal. Here, we use the immune system as a model to demonstrate the complex interplay between transcription factors and the chromatin landscape required to orchestrate precise gene responses to external stimuli and further to demonstrate how these interactions can establish memory of past transcriptional events. We focus on what we have learnt from the immune system and how this can inform our understanding of other cellular systems. © 2017 Elsevier Inc. All rights reserved.

Selective CD28 Antagonist Blunts Memory Immune Responses and Promotes Long-Term Control of Skin Inflammation in Nonhuman Primates.

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Poirier, Nicolas; Chevalier, Melanie; Mary, Caroline; Hervouet, Jeremy; Minault, David; Baker, Paul; Ville, Simon; Le Bas-Bernardet, Stephanie; Dilek, Nahzli; Belarif, Lyssia; Cassagnau, Elisabeth; Scobie, Linda; Blancho, Gilles; Vanhove, Bernard

2016-01-01

Novel therapies that specifically target activation and expansion of pathogenic immune cell subsets responsible for autoimmune attacks are needed to confer long-term remission. Pathogenic cells in autoimmunity include memory T lymphocytes that are long-lived and present rapid recall effector functions with reduced activation requirements. Whereas the CD28 costimulation pathway predominantly controls priming of naive T cells and hence generation of adaptive memory cells, the roles of CD28 costimulation on established memory T lymphocytes and the recall of memory responses remain controversial. In contrast to CD80/86 antagonists (CTLA4-Ig), selective CD28 antagonists blunt T cell costimulation while sparing CTLA-4 and PD-L1-dependent coinhibitory signals. Using a new selective CD28 antagonist, we showed that Ag-specific reactivation of human memory T lymphocytes was prevented. Selective CD28 blockade controlled both cellular and humoral memory recall in nonhuman primates and induced long-term Ag-specific unresponsiveness in a memory T cell-mediated inflammatory skin model. No modification of memory T lymphocytes subsets or numbers was observed in the periphery, and importantly no significant reactivation of quiescent viruses was noticed. These findings indicate that pathogenic memory T cell responses are controlled by both CD28 and CTLA-4/PD-L1 cosignals in vivo and that selectively targeting CD28 would help to promote remission of autoimmune diseases and control chronic inflammation. Copyright © 2015 by The American Association of Immunologists, Inc.

LOCAL IMMUNITY BY TISSUE-RESIDENT CD8+ MEMORY T CELLS

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Thomas eGebhardt

2012-11-01

Full Text Available Microbial infection primes a CD8+ cytotoxic T cell response that gives rise to a long-lived population of circulating memory cells able to provide protection against systemic reinfection. Despite this, effective CD8+ T cell surveillance of barrier tissues such as skin and mucosa typically wanes with time, resulting in limited T cell-mediated protection in these peripheral tissues. However, recent evidence suggests that a specialized subset of CD103+ memory T cells can permanently lodge and persist in peripheral tissues, and that these cells can compensate for the loss of peripheral immune surveillance by circulating memory T cells. Here, we review evolving concepts regarding the generation and long-term persistence of these tissue-resident memory T cells (TRM in epithelial and neuronal tissues. We further discuss the role of TRM cells in local infection control and their contribution to localized immune phenomena, in both mice and humans.

Immune responses of pigs inoculated with a recombinant fowlpox ...

African Journals Online (AJOL)

Yomi

2012-04-03

Apr 3, 2012 ... Key words: PCV2, rFPV, FMDV, immune response, prime-boost. .... After 10 min in the dark at room temperature, the color reaction was terminated with 50 µl of ..... ponses and improve memory and/or effector cell responses ...

Age related changes in T cell mediated immune response and effector memory to Respiratory Syncytial Virus (RSV in healthy subjects

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Campoccia Giuseppe

2010-10-01

Full Text Available Abstract Respiratory syncytial virus (RSV is the major pathogen causing respiratory disease in young infants and it is an important cause of serious illness in the elderly since the infection provides limited immune protection against reinfection. In order to explain this phenomenon, we investigated whether healthy adults of different age (20-40; 41-60 and > 60 years, have differences in central and effector memory, RSV-specific CD8+ T cell memory immune response and regulatory T cell expression status. In the peripheral blood of these donors, we were unable to detect any age related difference in term of central (CD45RA-CCR7+ and effector (CD45RA-CCR7- memory T cell frequency. On the contrary, we found a significant increase in immunosuppressive regulatory (CD4+25+FoxP3+ T cells (Treg in the elderly. An immunocytofluorimetric RSV pentamer analysis performed on these donors' peripheral blood mononuclear cells (PBMCs, in vitro sensitized against RSV antigen, revealed a marked decline in long-lasting RSV specific CD8+ memory T cell precursors expressing interleukin 7 receptor α (IL-7Rα, in the elderly. This effect was paralleled by a progressive switch from a Th1 (IFN-γ and TNF-α to a Th2 (IL-10 functional phenotype. On the contrary, an increase in Treg was observed with aging. The finding of Treg over-expression status, a prominent Th2 response and an inefficient RSV-specific effector memory CD8+ T cell expansion in older donors could explain the poor protection against RSV reinfection and the increased risk to develop an RSV-related severe illness in this population. Our finding also lays the basis for new therapeutic perspectives that could limit or prevent severe RSV infection in elderly.

Optimal approximation of linear systems by artificial immune response

Institute of Scientific and Technical Information of China (English)

无

2006-01-01

This paper puts forward a novel artificial immune response algorithm for optimal approximation of linear systems. A quaternion model of artificial immune response is proposed for engineering computing. The model abstracts four elements, namely, antigen, antibody, reaction rules among antibodies, and driving algorithm describing how the rules are applied to antibodies, to simulate the process of immune response. Some reaction rules including clonal selection rules, immunological memory rules and immune regulation rules are introduced. Using the theorem of Markov chain, it is proofed that the new model is convergent. The experimental study on the optimal approximation of a stable linear system and an unstable one show that the approximate models searched by the new model have better performance indices than those obtained by some existing algorithms including the differential evolution algorithm and the multi-agent genetic algorithm.

Memory B-Cell and Antibody Responses Induced by Plasmodium falciparum Sporozoite Immunization

NARCIS (Netherlands)

Nahrendorf, W.; Scholzen, A.; Bijker, E.M.; Teirlinck, A.C.; Bastiaens, G.J.H.; Schats, R.; Hermsen, C.C.; Visser, L.G.; Langhorne, J.; Sauerwein, R.W.

2014-01-01

BACKGROUND: Immunization of healthy volunteers during receipt of chemoprophylaxis with Plasmodium falciparum sporozoites (CPS-immunization) induces sterile protection from malaria. Antibody responses have long been known to contribute to naturally acquired immunity against malaria, but their

Cell-mediated and humoral immune responses in pigs following primary and challenge-exposure to Lawsonia intracellularis

DEFF Research Database (Denmark)

Hvass, Henriette Cordes; Riber, Ulla; Jensen, Tim Kåre

2012-01-01

not boosted by the re-inoculation, since identical intestinal IgA responses developed in response to the inoculation in both the susceptible CC pigs and the protected RE pigs. A memory recall cell-mediated immune response developed in RE pigs which was significantly stronger compared to the primary response...... responses are likely mediators of protective immunity against L. intracellularis, with CD8+ effector cells and CD4+CD8+ double positive memory T cells as main contributors to the antigen-specific IFN-γ production....

Streptococcal Immunity Is Constrained by Lack of Immunological Memory following a Single Episode of Pyoderma.

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Manisha Pandey

2016-12-01

Full Text Available The immunobiology underlying the slow acquisition of skin immunity to group A streptococci (GAS, is not understood, but attributed to specific virulence factors impeding innate immunity and significant antigenic diversity of the type-specific M-protein, hindering acquired immunity. We used a number of epidemiologically distinct GAS strains to model the development of acquired immunity. We show that infection leads to antibody responses to the serotype-specific determinants on the M-protein and profound protective immunity; however, memory B cells do not develop and immunity is rapidly lost. Furthermore, antibodies do not develop to a conserved M-protein epitope that is able to induce immunity following vaccination. However, if re-infected with the same strain within three weeks, enduring immunity and memory B-cells (MBCs to type-specific epitopes do develop. Such MBCs can adoptively transfer protection to naïve recipients. Thus, highly protective M-protein-specific MBCs may never develop following a single episode of pyoderma, contributing to the slow acquisition of immunity and to streptococcal endemicity in at-risk populations.

Immunization of neonatal mice with LAMP/p55 HIV gag DNA elicits robust immune responses that last to adulthood

International Nuclear Information System (INIS)

Ordonhez Rigato, Paula; Maciel, Milton; Goldoni, Adriana Leticia; Piubelli, Orlando; Alves de Brito, Cyro; Fusaro, Ana Elisa; Eurico de Alencar, Liciana Xavier; August, Thomas; Torres Azevedo Marques, Ernesto; Silva Duarte, Alberto Jose da; Sato, Maria Notomi

2010-01-01

Successful T cell priming in early postnatal life that can generate effective long-lasting responses until adulthood is critical in HIV vaccination strategies because it prevents early sexual initiation and breastfeeding transmission of HIV. A chimeric DNA vaccine encoding p55 HIV gag associated with lysosome-associated membrane protein 1 (LAMP-1; which drives the antigen to the MIIC compartment), has been used to enhance cellular and humoral antigen-specific responses in adult mice and macaques. Herein, we investigated LAMP-1/gag vaccine immunogenicity in the neonatal period in mice and its ability to generate long-lasting effects. Neonatal vaccination with chimeric LAMP/gag generated stronger Gag-specific immune responses, as measured by the breadth of the Gag peptide-specific IFN-γ, proliferative responsiveness, cytokine production and antibody production, all of which revealed activation of CD4+ T cells as well as the generation of a more robust CTL response compared to gag vaccine alone. To induce long-lived T and B cell memory responses, it was necessary to immunize neonates with the chimeric LAMP/gag DNA vaccine. The LAMP/gag DNA vaccine strategy could be particularly useful for generating an anti-HIV immune response in the early postnatal period capable of inducing long-term immunological memory.

Autologous Stem Cell Transplantation Disrupts Adaptive Immune Responses during Rebound Simian/Human Immunodeficiency Virus Viremia.

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Reeves, Daniel B; Peterson, Christopher W; Kiem, Hans-Peter; Schiffer, Joshua T

2017-07-01

Primary HIV-1 infection induces a virus-specific adaptive/cytolytic immune response that impacts the plasma viral load set point and the rate of progression to AIDS. Combination antiretroviral therapy (cART) suppresses plasma viremia to undetectable levels that rebound upon cART treatment interruption. Following cART withdrawal, the memory component of the virus-specific adaptive immune response may improve viral control compared to primary infection. Here, using primary infection and treatment interruption data from macaques infected with simian/human immunodeficiency virus (SHIV), we observe a lower peak viral load but an unchanged viral set point during viral rebound. The addition of an autologous stem cell transplant before cART withdrawal alters viral dynamics: we found a higher rebound set point but similar peak viral loads compared to the primary infection. Mathematical modeling of the data that accounts for fundamental immune parameters achieves excellent fit to heterogeneous viral loads. Analysis of model output suggests that the rapid memory immune response following treatment interruption does not ultimately lead to better viral containment. Transplantation decreases the durability of the adaptive immune response following cART withdrawal and viral rebound. Our model's results highlight the impact of the endogenous adaptive immune response during primary SHIV infection. Moreover, because we capture adaptive immune memory and the impact of transplantation, this model will provide insight into further studies of cure strategies inspired by the Berlin patient. IMPORTANCE HIV patients who interrupt combination antiretroviral therapy (cART) eventually experience viral rebound, the return of viral loads to pretreatment levels. However, the "Berlin patient" remained free of HIV rebound over a decade after stopping cART. His cure is attributed to leukemia treatment that included an HIV-resistant stem cell transplant. Inspired by this case, we studied the impact

17D yellow fever vaccine elicits comparable long-term immune responses in healthy individuals and immune-compromised patients.

Science.gov (United States)

Wieten, R W; Goorhuis, A; Jonker, E F F; de Bree, G J; de Visser, A W; van Genderen, P J J; Remmerswaal, E B M; Ten Berge, I J M; Visser, L G; Grobusch, M P; van Leeuwen, E M M

2016-06-01

The 17D live attenuated yellow fever (YF) vaccine is contra-indicated in immune-compromised individuals and may elicit a suboptimal immunologic response. The aim of this study is to assess whether long-term immune responses against the YF vaccine are impaired in immune-compromised patients. Fifteen patients using different immunosuppressive drugs and 30 healthy individuals vaccinated 0-22 years ago were included. The serological response was measured using the plaque reduction neutralization test (PRNT). CD8(+) and CD4(+) T-cell responses were measured following proliferation and re-stimulation with YFV peptide pools. Phenotypic characteristics and cytokine responses of CD8(+) T-cells were determined using class I tetramers. The geometric mean titre of neutralizing antibodies was not different between the groups (p = 0.77). The presence of YFV-specific CD4(+) and CD8(+) T-cell did not differ between patients and healthy individuals (15/15, 100.0% vs. 29/30, 96.7%, p = 0.475). Time since vaccination correlated negatively with the number of YFV-specific CD8(+) T-cells (r = -0.66, p = 0.0045). Percentages of early-differentiated memory cells increased (r = 0.67, p = 0.017) over time. These results imply that YF vaccination is effective despite certain immunosuppressive drug regimens. An early-differentiated memory-like phenotype persisted, which is associated with effective expansion upon re-encounter with antigen, suggesting a potent memory T-cell pool remains. Copyright © 2016 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Long-term persistence of immunity and B-cell memory following Haemophilus influenzae type B conjugate vaccination in early childhood and response to booster.

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Perrett, K P; John, T M; Jin, C; Kibwana, E; Yu, L-M; Curtis, N; Pollard, A J

2014-04-01

Protection against Haemophilus influenzae type b (Hib), a rapidly invading encapsulated bacteria, is dependent on maintenance of an adequate level of serum antibody through early childhood. In many countries, Hib vaccine booster doses have been implemented after infant immunization to sustain immunity. We investigated the long-term persistence of antibody and immunological memory in primary-school children following infant (with or without booster) Hib vaccination. Anti-polyribosylribitol phosphate (PRP) immunoglobulin G (IgG) concentration and the frequency of circulating Hib-specific memory B cells were measured before a booster of a Hib-serogroup C meningococcal (MenC) conjugate vaccine and again 1 week, 1 month, and 1 year after the booster in 250 healthy children aged 6-12 years in an open-label phase 4 clinical study. Six to 12 years following infant priming with 3 doses of Hib conjugate vaccine, anti-PRP IgG geometric mean concentrations were 3.11 µg/mL and 0.71 µg/mL and proportions with anti-PRP IgG ≥1.0 µg/mL were 79% and 43% in children who had or had not, respectively, received a fourth Hib conjugate vaccine dose (mean age, 3.9 years). Higher baseline and post-Hib-MenC booster responses (anti-PRP IgG and memory B cells) were found in younger children and in those who had received a fourth Hib dose. Sustained Hib conjugate vaccine-induced immunity in children is dependent on time since infant priming and receipt of a booster. Understanding the relationship between humoral and cellular immunity following immunization with conjugate vaccines may direct vaccine design and boosting strategies to sustain individual and population immunity against encapsulated bacteria in early childhood. Clinical Trials Registration ISRCTN728588998.

Microarray expression analysis of genes involved in innate immune memory in peritoneal macrophages

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Keisuke Yoshida

2016-03-01

Full Text Available Immunological memory has been believed to be a feature of the adaptive immune system for long period, but recent reports suggest that the innate immune system also exhibits memory-like reaction. Although evidence of innate immune memory is accumulating, no in vivo experimental data has clearly implicated a molecular mechanism, or even a cell-type, for this phenomenon. In this study of data deposited into Gene Expression Omnibus (GEO under GSE71111, we analyzed the expression profile of peritoneal macrophages isolated from mice pre-administrated with toll-like receptor (TLR ligands, mimicking pathogen infection. In these macrophages, increased expression of a group of innate immunity-related genes was sustained over a long period of time, and these genes overlapped with ATF7-regulated genes. We conclude that ATF7 plays an important role in innate immune memory in macrophages. Keywords: Macrophage, ATF7, Innate immune memory, Microarray

Experimental Chagas disease in Balb/c mice previously vaccinated with T. rangeli. II. The innate immune response shows immunological memory: reality or fiction?

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Basso, B; Marini, V

2015-03-01

Trypanosoma cruzi is a real challenge to the host's immune system, because it requires strong humoral and cellular immune response to remove circulating trypomastigote forms, and to prevent the replication of amastigote forms in tissues, involving many regulator and effector components. This protozoan is responsible for Chagas disease, a major public health problem in Latinamerica. We have developed a model of vaccination with Trypanosoma rangeli, a parasite closely related to T. cruzi, but nonpathogenic to humans, which reduces the infectiousness in three different species of animals, mice, dogs and guinea pigs, against challenge with T. cruzi. In a previous work, we demonstrated that mice vaccinated with T. rangeli showed important soluble mediators that stimulate phagocytic activity versus only infected groups. The aim of this work was to study the innate immune response in mice vaccinated or not with T. rangeli. Different population cells and some soluble mediators (cytokines) in peritoneal fluid and plasma in mice vaccinated-infected and only infected with T. cruzi were studied. In the first hours of challenge vaccinated mice showed an increase of macrophages, NK, granulocytes, and regulation of IL6, IFNγ, TNFα and IL10, with an increase of IL12, with respect to only infected mice. Furthermore an increase was observed of Li T, Li B responsible for adaptative response. Finally the findings showed that the innate immune response plays an important role in vaccinated mice for the early elimination of the parasites, complementary with the adaptative immune response, suggesting that vaccination with T. rangeli modulates the innate response, which develops some kind of immunological memory, recognizing shared antigens with T. cruzi. These results could contribute to the knowledge of new mechanisms which would have an important role in the immune response to Chagas disease. Copyright © 2014 Elsevier GmbH. All rights reserved.

An Immune-inspired Adaptive Automated Intrusion Response System Model

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Ling-xi Peng

2012-09-01

Full Text Available An immune-inspired adaptive automated intrusion response system model, named as , is proposed. The descriptions of self, non-self, immunocyte, memory detector, mature detector and immature detector of the network transactions, and the realtime network danger evaluation equations are given. Then, the automated response polices are adaptively performed or adjusted according to the realtime network danger. Thus, not only accurately evaluates the network attacks, but also greatly reduces the response times and response costs.

The cryo-thermal therapy eradicated melanoma in mice by eliciting CD4+ T-cell-mediated antitumor memory immune response.

Science.gov (United States)

He, Kun; Liu, Ping; Xu, Lisa X

2017-03-23

Tumor metastasis is a major concern in tumor therapy. In our previous studies, a novel tumor therapeutic modality of the cryo-thermal therapy has been presented, highlighting its effect on the suppression of distal metastasis and leading to long-term survival in 4T1 murine mammary carcinoma model. To demonstrate the therapeutic efficacy in other aggressive tumor models and further investigate the mechanism of long-term survival induced, in this study, spontaneous metastatic murine B16F10 melanoma model was used. The cryo-thermal therapy induced regression of implanted melanoma and prolonged long-term survival while inhibiting lung metastasis. It also promoted the activation of CD4 + CD25 - conventional T cells, while reduced the percentage of CD4 + CD25 + regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) in the spleen, lung and blood. Furthermore, the cryo-thermal therapy enhanced the cytolytic function of CD8 + T cells and induced differentiation of CD8 + T cells into memory stem T cell (T SCM ), and differentiation of CD4 + T cells into dominant CD4-CTL, Th1 and Tfh subsets in the spleen for 90 days after the treatment. It was found that good therapeutic effect was mainly dependent on CD4 + T cells providing a durable memory antitumor immune response. At the same time, significant increase of serum IFN-γ was also observed to provide an ideal microenvironment of antitumor immunity. Further study showed that the rejection of re-challenge of B16F10 but not GL261 tumor in the treated mice in 45 or 60 days after the treatment, implied a strong systemic and melanoma-specific memory antitumor immunity induced by the treatment. Thus the cryo-thermal therapy would be considered as a new therapeutic strategy to prevent tumor recurrence and metastasis with potential clinical applications in the near future.

Through the Immune Looking Glass: A Model for Brain Memory Strategies.

Science.gov (United States)

Sánchez-Ramón, Silvia; Faure, Florence

2016-01-01

The immune system (IS) and the central nervous system (CNS) are complex cognitive networks involved in defining the identity (self) of the individual through recognition and memory processes that enable one to anticipate responses to stimuli. Brain memory has traditionally been classified as either implicit or explicit on psychological and anatomical grounds, with reminiscences of the evolutionarily-based innate-adaptive IS responses. Beyond the multineuronal networks of the CNS, we propose a theoretical model of brain memory integrating the CNS as a whole. This is achieved by analogical reasoning between the operational rules of recognition and memory processes in both systems, coupled to an evolutionary analysis. In this new model, the hippocampus is no longer specifically ascribed to explicit memory but rather it both becomes part of the innate (implicit) memory system and tightly controls the explicit memory system. Alike the antigen presenting cells for the IS, the hippocampus would integrate transient and pseudo-specific (i.e., danger-fear) memories and would drive the formation of long-term and highly specific or explicit memories (i.e., the taste of the Proust's madeleine cake) by the more complex and recent, evolutionarily speaking, neocortex. Experimental and clinical evidence is provided to support the model. We believe that the singularity of this model's approximation could help to gain a better understanding of the mechanisms operating in brain memory strategies from a large-scale network perspective.

Through the Immune Looking Glass: A Model for Brain Memory Strategies.

Directory of Open Access Journals (Sweden)

Silvia eSánchez-Ramón

2016-02-01

Full Text Available The immune system (IS and the central nervous system (CNS are complex cognitive networks involved in defining the identity (self of the individual through recognition and memory processes that enable one to anticipate responses to stimuli. Brain memory has traditionally been classified as either implicit or explicit on psychological and anatomical grounds, with reminiscences of the evolutionarily-based innate-adaptive IS responses. Beyond the multineuronal networks of the CNS, we propose a theoretical model of brain memory integrating the CNS as a whole. This is achieved by analogical reasoning between the operational rules of recognition and memory processes in both systems, coupled to an evolutionary analysis. In this new model, the hippocampus is no longer specifically ascribed to explicit memory but rather it both becomes part of the innate (implicit memory system and tightly controls the explicit memory system. Alike the antigen presenting cells for the IS, the hippocampus would integrate transient and pseudo-specific (i.e. danger-fear memories and would drive the formation of long-term and highly specific or explicit memories (i.e. the taste of the Proust’s madeleine cake by the more complex and recent, evolutionarily speaking, neocortex. Experimental and clinical evidence is provided to support the model. We believe that the singularity of this model’s approximation could help to gain a better understanding of the mechanisms operating in brain memory strategies from a large-scale network perspective.

Through the Immune Looking Glass: A Model for Brain Memory Strategies

Science.gov (United States)

Sánchez-Ramón, Silvia; Faure, Florence

2016-01-01

The immune system (IS) and the central nervous system (CNS) are complex cognitive networks involved in defining the identity (self) of the individual through recognition and memory processes that enable one to anticipate responses to stimuli. Brain memory has traditionally been classified as either implicit or explicit on psychological and anatomical grounds, with reminiscences of the evolutionarily-based innate-adaptive IS responses. Beyond the multineuronal networks of the CNS, we propose a theoretical model of brain memory integrating the CNS as a whole. This is achieved by analogical reasoning between the operational rules of recognition and memory processes in both systems, coupled to an evolutionary analysis. In this new model, the hippocampus is no longer specifically ascribed to explicit memory but rather it both becomes part of the innate (implicit) memory system and tightly controls the explicit memory system. Alike the antigen presenting cells for the IS, the hippocampus would integrate transient and pseudo-specific (i.e., danger-fear) memories and would drive the formation of long-term and highly specific or explicit memories (i.e., the taste of the Proust’s madeleine cake) by the more complex and recent, evolutionarily speaking, neocortex. Experimental and clinical evidence is provided to support the model. We believe that the singularity of this model’s approximation could help to gain a better understanding of the mechanisms operating in brain memory strategies from a large-scale network perspective. PMID:26869886

Memory T-cell immune response in healthy young adults vaccinated with live attenuated influenza A (H5N2) vaccine.

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Chirkova, T V; Naykhin, A N; Petukhova, G D; Korenkov, D A; Donina, S A; Mironov, A N; Rudenko, L G

2011-10-01

Cellular immune responses of both CD4 and CD8 memory/effector T cells were evaluated in healthy young adults who received two doses of live attenuated influenza A (H5N2) vaccine. The vaccine was developed by reassortment of nonpathogenic avian A/Duck/Potsdam/1402-6/68 (H5N2) and cold-adapted A/Leningrad/134/17/57 (H2N2) viruses. T-cell responses were measured by standard methods of intracellular cytokine staining of gamma interferon (IFN-γ)-producing cells and a novel T-cell recognition of antigen-presenting cells by protein capture (TRAP) assay based on the trogocytosis phenomenon, namely, plasma membrane exchange between interacting immune cells. TRAP enables the detection of activated trogocytosis-positive T cells after virus stimulation. We showed that two doses of live attenuated influenza A (H5N2) vaccine promoted both CD4 and CD8 T-memory-cell responses in peripheral blood of healthy young subjects in the clinical study. Significant differences in geometric mean titers (GMTs) of influenza A (H5N2)-specific IFN-γ(+) cells were observed at day 42 following the second vaccination, while peak levels of trogocytosis(+) T cells were detected earlier, on the 21st day after the second vaccination. The inverse correlation of baseline levels compared to postvaccine fold changes in GMTs of influenza-specific CD4 and CD8 T cells demonstrated that baseline levels of these specific cells could be considered a predictive factor of vaccine immunogenicity.

Neonatal and Infantile Immune Responses to Encapsulated Bacteria and Conjugate Vaccines

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Peter Klein Klouwenberg

2008-01-01

Full Text Available Encapsulated bacteria are responsible for the majority of mortality among neonates and infants. The major components on the surface of these bacteria are polysaccharides which are important virulence factors. Immunity against these components protects against disease. However, most of the polysaccharides are thymus-independent (TI-2 antigens which induce an inadequate immune response in neonates and infants. The mechanisms that are thought to play a role in the unresponsiveness of this age group to TI-2 stimuli will be discussed. The lack of immune response may be overcome by conjugating the polysaccharides to a carrier protein. This transforms bacterial polysaccharides from a TI-2 antigen into a thymus-dependent (TD antigen, thereby inducing an immune response and immunological memory in neonates and infants. Such conjugated vaccines have been shown to be effective against the most common causes of invasive disease caused by encapsulated bacteria in neonates and children. These and several other approaches in current vaccine development will be discussed.

Brain-immune interaction accompanying odor-evoked autobiographic memory.

Science.gov (United States)

Matsunaga, Masahiro; Bai, Yu; Yamakawa, Kaori; Toyama, Asako; Kashiwagi, Mitsuyoshi; Fukuda, Kazuyuki; Oshida, Akiko; Sanada, Kazue; Fukuyama, Seisuke; Shinoda, Jun; Yamada, Jitsuhiro; Sadato, Norihiro; Ohira, Hideki

2013-01-01

The phenomenon in which a certain smell evokes a specific memory is known as the Proust phenomenon. Odor-evoked autobiographic memories are more emotional than those elicited by other sensory stimuli. The results of our previous study indicated that odor-evoked autobiographic memory accompanied by positive emotions has remarkable effects on various psychological and physiological activities, including the secretion of cytokines, which are immune-signaling molecules that modulate systemic inflammation. In this study, we aimed to clarify the neural substrates associated with the interaction between odor-evoked autobiographic memory and peripheral circulating cytokines. We recruited healthy male and female volunteers and investigated the association between brain responses and the concentration of several cytokines in the plasma by using positron emission tomography (PET) recordings when an autographic memory was evoked in participants by asking them to smell an odor that was nostalgic to them. Participants experienced positive emotions and autobiographic memories when nostalgic odors were presented to them. The levels of peripheral proinflammatory cytokines, such as the tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), were significantly reduced after experiencing odor-evoked autobiographic memory. Subtraction analysis of PET images indicated that the medial orbitofrontal cortex (mOFC) and precuneus/posterior cingulate cortex (PCC) were significantly activated during experiences of odor-evoked autobiographic memory. Furthermore, a correlation analysis indicated that activities of the mOFC and precuneus/PCC were negatively correlated with IFN-γ concentration. These results indicate that the neural networks including the precuneus/PCC and mOFC might regulate the secretion of peripheral proinflammatory cytokines during the experience of odor-evoked autobiographic memories accompanied with positive emotions.

Brain–Immune Interaction Accompanying Odor-Evoked Autobiographic Memory

Science.gov (United States)

Matsunaga, Masahiro; Bai, Yu; Yamakawa, Kaori; Toyama, Asako; Kashiwagi, Mitsuyoshi; Fukuda, Kazuyuki; Oshida, Akiko; Sanada, Kazue; Fukuyama, Seisuke; Shinoda, Jun; Yamada, Jitsuhiro; Sadato, Norihiro; Ohira, Hideki

2013-01-01

The phenomenon in which a certain smell evokes a specific memory is known as the Proust phenomenon. Odor-evoked autobiographic memories are more emotional than those elicited by other sensory stimuli. The results of our previous study indicated that odor-evoked autobiographic memory accompanied by positive emotions has remarkable effects on various psychological and physiological activities, including the secretion of cytokines, which are immune-signaling molecules that modulate systemic inflammation. In this study, we aimed to clarify the neural substrates associated with the interaction between odor-evoked autobiographic memory and peripheral circulating cytokines. We recruited healthy male and female volunteers and investigated the association between brain responses and the concentration of several cytokines in the plasma by using positron emission tomography (PET) recordings when an autographic memory was evoked in participants by asking them to smell an odor that was nostalgic to them. Participants experienced positive emotions and autobiographic memories when nostalgic odors were presented to them. The levels of peripheral proinflammatory cytokines, such as the tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), were significantly reduced after experiencing odor-evoked autobiographic memory. Subtraction analysis of PET images indicated that the medial orbitofrontal cortex (mOFC) and precuneus/posterior cingulate cortex (PCC) were significantly activated during experiences of odor-evoked autobiographic memory. Furthermore, a correlation analysis indicated that activities of the mOFC and precuneus/PCC were negatively correlated with IFN-γ concentration. These results indicate that the neural networks including the precuneus/PCC and mOFC might regulate the secretion of peripheral proinflammatory cytokines during the experience of odor-evoked autobiographic memories accompanied with positive emotions. PMID:23977312

Brain-immune interaction accompanying odor-evoked autobiographic memory.

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Masahiro Matsunaga

Full Text Available The phenomenon in which a certain smell evokes a specific memory is known as the Proust phenomenon. Odor-evoked autobiographic memories are more emotional than those elicited by other sensory stimuli. The results of our previous study indicated that odor-evoked autobiographic memory accompanied by positive emotions has remarkable effects on various psychological and physiological activities, including the secretion of cytokines, which are immune-signaling molecules that modulate systemic inflammation. In this study, we aimed to clarify the neural substrates associated with the interaction between odor-evoked autobiographic memory and peripheral circulating cytokines. We recruited healthy male and female volunteers and investigated the association between brain responses and the concentration of several cytokines in the plasma by using positron emission tomography (PET recordings when an autographic memory was evoked in participants by asking them to smell an odor that was nostalgic to them. Participants experienced positive emotions and autobiographic memories when nostalgic odors were presented to them. The levels of peripheral proinflammatory cytokines, such as the tumor necrosis factor-α (TNF-α and interferon-γ (IFN-γ, were significantly reduced after experiencing odor-evoked autobiographic memory. Subtraction analysis of PET images indicated that the medial orbitofrontal cortex (mOFC and precuneus/posterior cingulate cortex (PCC were significantly activated during experiences of odor-evoked autobiographic memory. Furthermore, a correlation analysis indicated that activities of the mOFC and precuneus/PCC were negatively correlated with IFN-γ concentration. These results indicate that the neural networks including the precuneus/PCC and mOFC might regulate the secretion of peripheral proinflammatory cytokines during the experience of odor-evoked autobiographic memories accompanied with positive emotions.

Trypanosoma cruzi vaccine candidate antigens Tc24 and TSA-1 recall memory immune response associated with HLA-A and -B supertypes in Chagasic chronic patients from Mexico.

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Villanueva-Lizama, Liliana E; Cruz-Chan, Julio V; Aguilar-Cetina, Amarú Del C; Herrera-Sanchez, Luis F; Rodriguez-Perez, Jose M; Rosado-Vallado, Miguel E; Ramirez-Sierra, Maria J; Ortega-Lopez, Jaime; Jones, Kathryn; Hotez, Peter; Bottazzi, Maria Elena; Dumonteil, Eric

2018-01-01

Trypanosoma cruzi antigens TSA-1 and Tc24 have shown promise as vaccine candidates in animal studies. We evaluated here the recall immune response these antigens induce in Chagasic patients, as a first step to test their immunogenicity in humans. We evaluated the in vitro cellular immune response after stimulation with recombinant TSA-1 (rTSA-1) or recombinant Tc24 (rTc24) in mononuclear cells of asymptomatic Chagasic chronic patients (n = 20) compared to healthy volunteers (n = 19) from Yucatan, Mexico. Proliferation assays, intracellular cytokine staining, cytometric bead arrays, and memory T cell immunophenotyping were performed by flow cytometry. Peripheral blood mononuclear cells (PBMC) from Chagasic patients showed significant proliferation after stimulation with rTc24 and presented a phenotype of T effector memory cells (CD45RA-CCR7-). These cells also produced IFN-γ and, to a lesser extent IL10, after stimulation with rTSA-1 and rTc24 proteins. Overall, both antigens recalled a broad immune response in some Chagasic patients, confirming that their immune system had been primed against these antigens during natural infection. Analysis of HLA-A and HLA-B allele diversity by PCR-sequencing indicated that HLA-A03 and HLA-B07 were the most frequent supertypes in this Mexican population. Also, there was a significant difference in the frequency of HLA-A01 and HLA-A02 supertypes between Chagasic patients and controls, while the other alleles were evenly distributed. Some aspects of the immune response, such as antigen-induced IFN-γ production by CD4+ and CD8+ T cells and CD8+ proliferation, showed significant association with specific HLA-A supertypes, depending on the antigen considered. In conclusion, our results confirm the ability of both TSA-1 and Tc24 recombinant proteins to recall an immune response induced by the native antigens during natural infection in at least some patients. Our data support the further development of these antigens as therapeutic

Immune system development during early childhood in tropical Latin America: evidence for the age-dependent down regulation of the innate immune response.

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Teran, Rommy; Mitre, Edward; Vaca, Maritza; Erazo, Silvia; Oviedo, Gisela; Hübner, Marc P; Chico, Martha E; Mattapallil, Joseph J; Bickle, Quentin; Rodrigues, Laura C; Cooper, Philip J

2011-03-01

The immune response that develops in early childhood underlies the development of inflammatory diseases such as asthma and there are few data from tropical Latin America (LA). This study investigated the effects of age on the development of immunity during the first 5 years of life by comparing innate and adaptive immune responses in Ecuadorian children aged 6-9 months, 22-26 months, and 48-60 months. Percentages of naïve CD4+ T cells declined with age while those of memory CD4(+) and CD8(+) T cells increased indicating active development of the immune system throughout the first five years. Young infants had greater innate immune responses to TLR agonists compared to older children while regulatory responses including SEB-induced IL-10 and percentages of FoxP3(+) T-regulatory cells decreased with age. Enhanced innate immunity in early life may be important for host defense against pathogens but may increase the risk of immunopathology. Copyright © 2010 Elsevier Inc. All rights reserved.

Multi-scale modeling of the CD8 immune response

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Barbarroux, Loic, E-mail: loic.barbarroux@doctorant.ec-lyon.fr [Inria, Université de Lyon, UMR 5208, Institut Camille Jordan (France); Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully (France); Michel, Philippe, E-mail: philippe.michel@ec-lyon.fr [Inria, Université de Lyon, UMR 5208, Institut Camille Jordan (France); Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully (France); Adimy, Mostafa, E-mail: mostafa.adimy@inria.fr [Inria, Université de Lyon, UMR 5208, Université Lyon 1, Institut Camille Jordan, 43 Bd. du 11 novembre 1918, F-69200 Villeurbanne Cedex (France); Crauste, Fabien, E-mail: crauste@math.univ-lyon1.fr [Inria, Université de Lyon, UMR 5208, Université Lyon 1, Institut Camille Jordan, 43 Bd. du 11 novembre 1918, F-69200 Villeurbanne Cedex (France)

2016-06-08

During the primary CD8 T-Cell immune response to an intracellular pathogen, CD8 T-Cells undergo exponential proliferation and continuous differentiation, acquiring cytotoxic capabilities to address the infection and memorize the corresponding antigen. After cleaning the organism, the only CD8 T-Cells left are antigen-specific memory cells whose role is to respond stronger and faster in case they are presented this very same antigen again. That is how vaccines work: a small quantity of a weakened pathogen is introduced in the organism to trigger the primary response, generating corresponding memory cells in the process, giving the organism a way to defend himself in case it encounters the same pathogen again. To investigate this process, we propose a non linear, multi-scale mathematical model of the CD8 T-Cells immune response due to vaccination using a maturity structured partial differential equation. At the intracellular scale, the level of expression of key proteins is modeled by a delay differential equation system, which gives the speeds of maturation for each cell. The population of cells is modeled by a maturity structured equation whose speeds are given by the intracellular model. We focus here on building the model, as well as its asymptotic study. Finally, we display numerical simulations showing the model can reproduce the biological dynamics of the cell population for both the primary response and the secondary responses.

Lifelong memory responses perpetuate humoral TH2 immunity and anaphylaxis in food allergy.

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Jiménez-Saiz, Rodrigo; Chu, Derek K; Mandur, Talveer S; Walker, Tina D; Gordon, Melissa E; Chaudhary, Roopali; Koenig, Joshua; Saliba, Sarah; Galipeau, Heather J; Utley, Adam; King, Irah L; Lee, Kelvin; Ettinger, Rachel; Waserman, Susan; Kolbeck, Roland; Jordana, Manel

2017-12-01

A number of food allergies (eg, fish, shellfish, and nuts) are lifelong, without any disease-transforming therapies, and unclear in their underlying immunology. Clinical manifestations of food allergy are largely mediated by IgE. Although persistent IgE titers have been attributed conventionally to long-lived IgE + plasma cells (PCs), this has not been directly and comprehensively tested. We sought to evaluate mechanisms underlying persistent IgE and allergic responses to food allergens. We used a model of peanut allergy and anaphylaxis, various knockout mice, adoptive transfer experiments, and in vitro assays to identify mechanisms underlying persistent IgE humoral immunity over almost the entire lifespan of the mouse (18-20 months). Contrary to conventional paradigms, our data show that clinically relevant lifelong IgE titers are not sustained by long-lived IgE + PCs. Instead, lifelong reactivity is conferred by allergen-specific long-lived memory B cells that replenish the IgE + PC compartment. B-cell reactivation requires allergen re-exposure and IL-4 production by CD4 T cells. We define the half-lives of antigen-specific germinal centers (23.3 days), IgE + and IgG 1 + PCs (60 and 234.4 days, respectively), and clinically relevant cell-bound IgE (67.3 days). These findings can explain lifelong food allergies observed in human subjects as the consequence of allergen exposures that recurrently activate memory B cells and identify these as a therapeutic target with disease-transforming potential. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Mucosal immunization in macaques upregulates the innate APOBEC 3G anti-viral factor in CD4(+) memory T cells.

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Wang, Yufei; Bergmeier, Lesley A; Stebbings, Richard; Seidl, Thomas; Whittall, Trevor; Singh, Mahavir; Berry, Neil; Almond, Neil; Lehner, Thomas

2009-02-05

APOBEC3G is an innate intracellular anti-viral factor which deaminates retroviral cytidine to uridine. In vivo studies of APOBEC3G (A3G) were carried out in rhesus macaques, following mucosal immunization with SIV antigens and CCR5 peptides, linked to the 70kDa heat shock protein. A progressive increase in A3G mRNA was elicited in PBMC after each immunization (p<0.0002 to p< or =0.02), which was maintained for at least 17 weeks. Analysis of memory T cells showed a significant increase in A3G mRNA and protein in CD4(+)CCR5(+) memory T cells in circulating (p=0.0001), splenic (p=0.0001), iliac lymph nodes (p=0.002) and rectal (p=0.01) cells of the immunized compared with unimmunized macaques. Mucosal challenge with SIVmac 251 showed a significant increase in A3G mRNA in the CD4(+)CCR5(+) circulating cells (p<0.01) and the draining iliac lymph node cells (p<0.05) in the immunized uninfected macaques, consistent with a protective effect exerted by A3G. The results suggest that mucosal immunization in a non-human primate can induce features of a memory response to an innate anti-viral factor in CCR5(+)CD4(+) memory and CD4(+)CD95(+)CCR7(-) effector memory T cells.

Complex multicellular functions at a unicellular eukaryote level: Learning, memory, and immunity.

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Csaba, György

2017-06-01

According to experimental data, eukaryote unicellulars are able to learn, have immunity and memory. Learning is carried out in a very primitive form, and the memory is not neural but an epigenetic one. However, this epigenetic memory, which is well justified by the presence and manifestation of hormonal imprinting, is strong and permanent in the life of cell and also in its progenies. This memory is epigenetically executed by the alteration and fixation of methylation pattern of genes without changes in base sequences. The immunity of unicellulars is based on self/non-self discrimination, which leads to the destruction of non-self invaders and utilization of them as nourishment (by phagocytosis). The tools of learning, memory, and immunity of unicellulars are uniformly found in plasma membrane receptors, which formed under the effect of dynamic receptor pattern generation, suggested by Koch et al., and this is the basis of hormonal imprinting, by which the encounter between a chemical substance and the cell is specifically memorized. The receptors and imprinting are also used in the later steps of evolution up to mammals (including man) in each mentioned functions. This means that learning, memory, and immunity can be deduced to a unicellular eukaryote level.

Tailoring the Immune Response via Customization of Pathogen Gene Expression.

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Runco, Lisa M; Stauft, Charles B; Coleman, J Robert

2014-01-01

The majority of studies focused on the construction and reengineering of bacterial pathogens have mainly relied on the knocking out of virulence factors or deletion/mutation of amino acid residues to then observe the microbe's phenotype and the resulting effect on the host immune response. These knockout bacterial strains have also been proposed as vaccines to combat bacterial disease. Theoretically, knockout strains would be unable to cause disease since their virulence factors have been removed, yet they could induce a protective memory response. While knockout strains have been valuable tools to discern the role of virulence factors in host immunity and bacterial pathogenesis, they have been unable to yield clinically relevant vaccines. The advent of synthetic biology and enhanced user-directed gene customization has altered this binary process of knockout, followed by observation. Recent studies have shown that a researcher can now tailor and customize a given microbe's gene expression to produce a desired immune response. In this commentary, we highlight these studies as a new avenue for controlling the inflammatory response as well as vaccine development.

The Memories of NK Cells: Innate-Adaptive Immune Intrinsic Crosstalk.

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Gabrielli, Sara; Ortolani, Claudio; Del Zotto, Genny; Luchetti, Francesca; Canonico, Barbara; Buccella, Flavia; Artico, Marco; Papa, Stefano; Zamai, Loris

2016-01-01

Although NK cells are considered part of the innate immune system, a series of evidences has demonstrated that they possess characteristics typical of the adaptive immune system. These NK adaptive features, in particular their memory-like functions, are discussed from an ontogenetic and evolutionary point of view.

The Memories of NK Cells: Innate-Adaptive Immune Intrinsic Crosstalk

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Sara Gabrielli

2016-01-01

Full Text Available Although NK cells are considered part of the innate immune system, a series of evidences has demonstrated that they possess characteristics typical of the adaptive immune system. These NK adaptive features, in particular their memory-like functions, are discussed from an ontogenetic and evolutionary point of view.

Cell-mediated immune responses in the head-associated lymphoid tissues induced to a live attenuated avian coronavirus vaccine.

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Gurjar, Rucha S; Gulley, Stephen L; van Ginkel, Frederik W

2013-12-01

Humoral immunity is important for controlling viral diseases of poultry, but recent studies have indicated that cytotoxic T cells also play an important role in the immune response to infectious bronchitis virus (IBV). To better understand the cell mediated immune responses to IBV in the mucosal and systemic immune compartments chickens were ocularly vaccinated with IBV. This induced a lymphocyte expansion in head-associated lymphoid tissues (HALT) and to a lesser extent in the spleen, followed by a rapid decline, probably due to homing of lymphocytes out of these organs and contraction of the lymphocyte population. This interpretation was supported by observations that changes in mononuclear cells were mirrored by that in CD3(+)CD44(+) T cell abundance, which presumably represent T effector cells. Increased interferon gamma (IFN-γ) expression was observed in the mucosal immune compartment, i.e., HALT, after primary vaccination, but shifted to the systemic immune compartment after boosting. In contrast, the expression of cytotoxicity-associated genes, i.e., granzyme A (GZMA) and perforin mRNA, remained associated with the HALT after boosting. Thus, an Ark-type IBV ocular vaccine induces a central memory IFN-γ response in the spleen while the cytotoxic effector memory response, as measured by GZMA and perforin mRNA expression, remains associated with CALT after boosting. Copyright © 2013. Published by Elsevier Ltd.

Liver-primed memory T cells generated under noninflammatory conditions provide anti-infectious immunity.

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Böttcher, Jan P; Schanz, Oliver; Wohlleber, Dirk; Abdullah, Zeinab; Debey-Pascher, Svenja; Staratschek-Jox, Andrea; Höchst, Bastian; Hegenbarth, Silke; Grell, Jessica; Limmer, Andreas; Atreya, Imke; Neurath, Markus F; Busch, Dirk H; Schmitt, Edgar; van Endert, Peter; Kolanus, Waldemar; Kurts, Christian; Schultze, Joachim L; Diehl, Linda; Knolle, Percy A

2013-03-28

Development of CD8(+) T cell (CTL) immunity or tolerance is linked to the conditions during T cell priming. Dendritic cells (DCs) matured during inflammation generate effector/memory T cells, whereas immature DCs cause T cell deletion/anergy. We identify a third outcome of T cell priming in absence of inflammation enabled by cross-presenting liver sinusoidal endothelial cells. Such priming generated memory T cells that were spared from deletion by immature DCs. Similar to central memory T cells, liver-primed T cells differentiated into effector CTLs upon antigen re-encounter on matured DCs even after prolonged absence of antigen. Their reactivation required combinatorial signaling through the TCR, CD28, and IL-12R and controlled bacterial and viral infections. Gene expression profiling identified liver-primed T cells as a distinct Neuropilin-1(+) memory population. Generation of liver-primed memory T cells may prevent pathogens that avoid DC maturation by innate immune escape from also escaping adaptive immunity through attrition of the T cell repertoire. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Liver-Primed Memory T Cells Generated under Noninflammatory Conditions Provide Anti-infectious Immunity

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Jan P. Böttcher

2013-03-01

Full Text Available Development of CD8+ T cell (CTL immunity or tolerance is linked to the conditions during T cell priming. Dendritic cells (DCs matured during inflammation generate effector/memory T cells, whereas immature DCs cause T cell deletion/anergy. We identify a third outcome of T cell priming in absence of inflammation enabled by cross-presenting liver sinusoidal endothelial cells. Such priming generated memory T cells that were spared from deletion by immature DCs. Similar to central memory T cells, liver-primed T cells differentiated into effector CTLs upon antigen re-encounter on matured DCs even after prolonged absence of antigen. Their reactivation required combinatorial signaling through the TCR, CD28, and IL-12R and controlled bacterial and viral infections. Gene expression profiling identified liver-primed T cells as a distinct Neuropilin-1+ memory population. Generation of liver-primed memory T cells may prevent pathogens that avoid DC maturation by innate immune escape from also escaping adaptive immunity through attrition of the T cell repertoire.

Systemic and Terminal Ileum Mucosal Immunity Elicited by Oral Immunization With the Ty21a Typhoid Vaccine in HumansSummary

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Jayaum S. Booth

2017-11-01

Full Text Available Background & Aims: Systemic cellular immunity elicited by the Ty21a oral typhoid vaccine has been extensively characterized. However, very limited data are available in humans regarding mucosal immunity at the site of infection (terminal ileum [TI]. Here we investigated the host immunity elicited by Ty21a immunization on terminal ileum–lamina propria mononuclear cells (LPMC and peripheral blood in volunteers undergoing routine colonoscopy. Methods: We characterized LPMC-T memory (TM subsets and assessed Salmonella enterica serovar Typhi (S Typhi–specific responses by multichromatic flow cytometry. Results: No differences were observed in cell yields and phenotypes in LPMC CD8+-TM subsets following Ty21a immunization. However, Ty21a immunization elicited LPMC CD8+ T cells exhibiting significant S Typhi–specific responses (interferon-γ, tumor necrosis factor-α, interleukin-17A, and/or CD107a in all major TM subsets (T-effector/memory [TEM], T-central/memory, and TEM-CD45RA+, although each TM subset exhibited unique characteristics. We also investigated whether Ty21a immunization elicited S Typhi–specific multifunctional effectors in LPMC CD8+ TEM. We observed that LPMC CD8+ TEM responses were mostly multifunctional, except for those cells exhibiting the characteristics associated with cytotoxic responses. Finally, we compared mucosal with systemic responses and made the important observation that LPMC CD8+ S Typhi–specific responses were unique and distinct from their systemic counterparts. Conclusions: This study provides the first demonstration of S Typhi–specific responses in the human terminal ileum mucosa and provides novel insights into the generation of mucosal immune responses following oral Ty21a immunization. Keywords: Lamina Propria Mononuclear Cells, Multifunctional T Cells, CD8+-T Memory Cells, Typhoid, Vaccines

Tumour cell lysate-loaded dendritic cell vaccine induces biochemical and memory immune response in castration-resistant prostate cancer patients.

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Reyes, D; Salazar, L; Espinoza, E; Pereda, C; Castellón, E; Valdevenito, R; Huidobro, C; Inés Becker, M; Lladser, A; López, M N; Salazar-Onfray, F

2013-09-17

Recently, we produced a tumour antigen-presenting cells (TAPCells) vaccine using a melanoma cell lysate, called TRIMEL, as an antigen source and an activation factor. Tumour antigen-presenting cells induced immunological responses and increased melanoma patient survival. Herein, we investigated the effect of TAPCells loaded with prostate cancer cell lysates (PCCL) as an antigen source, and TRIMEL as a dendritic cell (DC) activation factor; which were co-injected with the Concholepas concholepas haemocyanin (CCH) as an adjuvant on castration-resistant prostate cancer (CRPC) patients. The lysate mix capacity, for inducing T-cell activation, was analysed by flow cytometry and Elispot. Delayed-type hypersensitivity (DTH) reaction against PCCL, frequency of CD8(+) memory T cells (Tm) in blood and prostate-specific antigen (PSA) levels in serum were measured in treated patients. The lysate mix induced functional mature DCs that were capable of activating PCCL-specific T cells. No relevant adverse reactions were observed. Six out of 14 patients showed a significant decrease in levels of PSA. DTH(+) patients showed a prolonged PSA doubling-time after treatment. Expansion of functional central and effector CD8(+) Tm were detected. Treatment of CRPC patients with lysate-loaded TAPCells and CCH as an adjuvant is safe: generating biochemical and memory immune responses. However, the limited number of cases requires confirmation in a phase II clinical trial.

Immune responses to metastases

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Herberman, R.B.; Wiltrout, R.H.; Gorelik, E.

1987-01-01

The authors present the changes in the immune system in tumor-bearing hosts that may influence the development of progression of metastases. Included are mononuclear cell infiltration of metastases; alterations in natural resistance mediated by natural killer cells and macrophages; development of specific immunity mediated by T-lymphocytes or antibodies; modulation of tumor-associated antigen expression; and the down-regulation of the immune response to the tumor by several suppressor mechanisms; the augmentation of the immune response and its potential for therapeutic application; includes the prophylaxis of metastases formation by NK cells; the therapy of metastases by augmentation NK-, macrophage-, or T-lymphocyte-mediated responses by biological response modifiers; and the transfer of anticancer activity by cytoxic T-lymphocytes or immunoconjugates of monoclonal antibodies with specificity for tumors

Early appearance of germinal center–derived memory B cells and plasma cells in blood after primary immunization

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Blink, Elizabeth J.; Light, Amanda; Kallies, Axel; Nutt, Stephen L.; Hodgkin, Philip D.; Tarlinton, David M.

2005-01-01

Immunization with a T cell–dependent antigen elicits production of specific memory B cells and antibody-secreting cells (ASCs). The kinetic and developmental relationships between these populations and the phenotypic forms they and their precursors may take remain unclear. Therefore, we examined the early stages of a primary immune response, focusing on the appearance of antigen-specific B cells in blood. Within 1 wk, antigen-specific B cells appear in the blood with either a memory phenotype or as immunoglobulin (Ig)G1 ASCs expressing blimp-1. The memory cells have mutated VH genes; respond to the chemokine CXCL13 but not CXCL12, suggesting recirculation to secondary lymphoid organs; uniformly express B220; show limited differentiation potential unless stimulated by antigen; and develop independently of blimp-1 expression. The antigen-specific IgG1 ASCs in blood show affinity maturation paralleling that of bone marrow ASCs, raising the possibility that this compartment is established directly by blood-borne ASCs. We find no evidence for a blimp-1–expressing preplasma memory compartment, suggesting germinal center output is restricted to ASCs and B220+ memory B cells, and this is sufficient to account for the process of affinity maturation. PMID:15710653

Maternal immunity enhances systemic recall immune responses upon oral immunization of piglets with F4 fimbriae.

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Nguyen, Ut V; Melkebeek, Vesna; Devriendt, Bert; Goetstouwers, Tiphanie; Van Poucke, Mario; Peelman, Luc; Goddeeris, Bruno M; Cox, Eric

2015-06-23

F4 enterotoxigenic Escherichia coli (ETEC) cause diarrhoea and mortality in piglets leading to severe economic losses. Oral immunization of piglets with F4 fimbriae induces a protective intestinal immune response evidenced by an F4-specific serum and intestinal IgA response. However, successful oral immunization of pigs with F4 fimbriae in the presence of maternal immunity has not been demonstrated yet. In the present study we aimed to evaluate the effect of maternal immunity on the induction of a systemic immune response upon oral immunization of piglets. Whereas F4-specific IgG and IgA could be induced by oral immunization of pigs without maternal antibodies and by intramuscular immunization of pigs with maternal antibodies, no such response was seen in the orally immunized animals with maternal antibodies. Since maternal antibodies can mask an antibody response, we also looked by ELIspot assays for circulating F4-specific antibody secreting cells (ASCs). Enumerating the F4-specific ASCs within the circulating peripheral blood mononuclear cells, and the number of F4-specific IgA ASCs within the circulating IgA(+) B-cells revealed an F4-specific immune response in the orally immunized animals with maternal antibodies. Interestingly, results suggest a more robust IgA booster response by oral immunization of pigs with than without maternal antibodies. These results demonstrate that oral immunization of piglets with F4-specific maternal antibodies is feasible and that these maternal antibodies seem to enhance the secondary systemic immune response. Furthermore, our ELIspot assay on enriched IgA(+) B-cells could be used as a screening procedure to optimize mucosal immunization protocols in pigs with maternal immunity.

Characterization of an adaptive immune response in microsatellite-instable colorectal cancer

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Boissière-Michot, Florence; Lazennec, Gwendal; Frugier, Hélène; Jarlier, Marta; Roca, Lise; Duffour, Jacqueline; Du Paty, Emilie; Laune, Daniel; Blanchard, France; Le Pessot, Florence; Sabourin, Jean-Christophe; Bibeau, Frédéric

2014-01-01

Sporadic or hereditary colorectal cancer (CRC) with microsatellite instability (MSI) is frequently characterized by inflammatory lymphocytic infiltration and tends to be associated with a better outcome than microsatellite stable (MSS) CRC, probably reflecting a more effective immune response. We investigated inflammatory mechanisms in 48 MSI CRCs and 62 MSS CRCs by analyzing: (1) the expression of 48 cytokines using Bio-Plex multiplex cytokine assays, and (2) the in situ immune response by immunohistochemical analysis with antibodies against CD3 (T lymphocytes), CD8 (cytotoxic T lymphocytes), CD45RO (memory T lymphocytes), T-bet (Th1 CD4 cells), and FoxP3 (regulatory T cells). MSI CRC exhibited significantly higher expression of CCL5 (RANTES), CXCL8 (IL-8), CXCL9 (MIG), IL-1β, CXCL10 (IP-10), IL-16, CXCL1 (GROα), and IL-1ra, and lower expression of MIF, compared with MSS CRC. Immunohistochemistry combined with image analysis indicated that the density of CD3+, CD8+, CD45RO+, and T-bet+ T lymphocytes was higher in MSI CRC than in MSS CRC, whereas the number of regulatory T cells (FoxP3+) was not statistically different between the groups. These results indicate that MSI CRC is associated with a specific cytokine expression profile that includes CCL5, CXCL10, and CXCL9, which are involved in the T helper type 1 (Th1) response and in the recruitment of memory CD45RO+ T cells. Our findings highlight the major role of adaptive immunity in MSI CRC and provide a possible explanation for the more favorable prognosis of this CRC subtype. PMID:25101223

CpG in Combination with an Inhibitor of Notch Signaling Suppresses Formalin-Inactivated Respiratory Syncytial Virus-Enhanced Airway Hyperresponsiveness and Inflammation by Inhibiting Th17 Memory Responses and Promoting Tissue-Resident Memory Cells in Lungs.

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Zhang, Lei; Li, Hongyong; Hai, Yan; Yin, Wei; Li, Wenjian; Zheng, Boyang; Du, Xiaomin; Li, Na; Zhang, Zhengzheng; Deng, Yuqing; Zeng, Ruihong; Wei, Lin

2017-05-15

Respiratory syncytial virus (RSV) is the leading cause of childhood hospitalizations. The formalin-inactivated RSV (FI-RSV) vaccine-enhanced respiratory disease (ERD) has been an obstacle to the development of a safe and effective killed RSV vaccine. Agonists of Toll-like receptor (TLR) have been shown to regulate immune responses induced by FI-RSV. Notch signaling plays critical roles during the differentiation and effector function phases of innate and adaptive immune responses. Cross talk between TLR and Notch signaling pathways results in fine-tuning of TLR-triggered innate inflammatory responses. We evaluated the impact of TLR and Notch signaling on ERD in a murine model by administering CpG, an agonist of TLR9, in combination with L685,458, an inhibitor of Notch signaling during FI-RSV immunization. Activation with CpG or deficiency of MyD88-dependent TLR signaling did not alleviate airway inflammation in FI-RSV-immunized mice. Activation or inhibition of Notch signaling with Dll4, one of the Notch ligands, or L685,458 did not suppress FI-RSV-enhanced airway inflammation either. However, the CpG together with L685,458 markedly inhibited FI-RSV-enhanced airway hyperresponsiveness, weight loss, and lung inflammation. Interestingly, CpG plus L685,458 completely inhibited FI-RSV-associated Th17 and Th17-associated proinflammatory chemokine responses in lungs following RSV challenge but not Th1 or Th2, memory responses. In addition, FI-RSV plus CpG plus L685,458 promoted protective CD8 + lung tissue-resident memory (TRM) cells. These results indicate that activation of TLR signaling combined with inhibition of Notch signaling prevent FI-RSV ERD, and the mechanism appears to involve suppressing proinflammatory Th17 memory responses and promoting protective TRM in lungs. IMPORTANCE RSV is the most important cause of lower respiratory tract infections in infants. The FI-RSV-enhanced respiratory disease (ERD) is a major impediment to the development of a safe and

Association of Neisseria gonorrhoeae Opa(CEA with dendritic cells suppresses their ability to elicit an HIV-1-specific T cell memory response.

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Qigui Yu

Full Text Available Infection with Neisseria gonorrhoeae (N. gonorrhoeae can trigger an intense local inflammatory response at the site of infection, yet there is little specific immune response or development of immune memory. Gonococcal surface epitopes are known to undergo antigenic variation; however, this is unlikely to explain the weak immune response to infection since individuals can be re-infected by the same serotype. Previous studies have demonstrated that the colony opacity-associated (Opa proteins on the N. gonorrhoeae surface can bind human carcinoembryonic antigen-related cellular adhesion molecule 1 (CEACAM1 on CD4⁺ T cells to suppress T cell activation and proliferation. Interesting in this regard, N. gonorrhoeae infection is associated with impaired HIV-1 (human immunodeficiency virus type 1-specific cytotoxic T-lymphocyte (CTL responses and with transient increases in plasma viremia in HIV-1-infected patients, suggesting that N. gonorrhoeae may also subvert immune responses to co-pathogens. Since dendritic cells (DCs are professional antigen presenting cells (APCs that play a key role in the induction of an adaptive immune response, we investigated the effects of N. gonorrhoeae Opa proteins on human DC activation and function. While morphological changes reminiscent of DC maturation were evident upon N. gonorrhoeae infection, we observed a marked downregulation of DC maturation marker CD83 when the gonococci expressing CEACAM1-specific Opa(CEA, but not other Opa variants. Consistent with a gonococcal-induced defect in maturation, Opa(CEA binding to CEACAM1 reduced the DCs' capacity to stimulate an allogeneic T cell proliferative response. Moreover, Opa(CEA-expressing N. gonorrhoeae showed the potential to impair DC-dependent development of specific adaptive immunity, since infection with Opa(CEA-positive gonococci suppressed the ability of DCs to stimulate HIV-1-specific memory CTL responses. These results reveal a novel mechanism to explain

Contradictory Immune Response in Post Liver Transplantation Hepatitis B and C

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Akinobu Takaki

2014-01-01

Full Text Available Hepatitis B and C often progress to decompensated liver cirrhosis requiring orthotopic liver transplantation (OLT. After OLT, hepatitis B recurrence is clinically controlled with a combination of hepatitis B immunoglobulin (HBIG and nucleos(tide analogues. Another approach is to induce self-producing anti-hepatitis B virus (HBV antibodies using a HBV envelope antigen vaccine. Patients who had not been HBV carriers such as acutely infected liver failure or who received liver from HBV self-limited donor are good candidate. For chronic HBV carrier patients, a successful response can only be achieved in selected patients such as those treated with experimentally reduced immunosuppression protocols or received an anti-HBV adaptive memory carrying donor liver. Hepatitis C virus (HCV reinfects transplanted livers at a rate of >90%. HCV reinfected patients show different severities of hepatitis, from mild and slowly progressing to severe and rapidly progressing, possibly resulting from different adaptive immune responses. More than half the patients require interferon treatment, although the success rate is low and carries risks for leukocytopenia and rejection. Managing the immune response has an important role in controlling recurrent hepatitis C. This study aimed to review the adaptive immune response in post-OLT hepatitis B and C.

Effect of adjuvants on the humoral immune response to congopain in mice and cattle

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Kateregga John

2012-05-01

Full Text Available Abstract Background We investigated several adjuvants for their effects on the humoral immune response in both mice and cattle using the central domain of congopain (C2, the major cysteine protease of Trypanosoma congolense, as a model for developing a vaccine against animal trypanosomosis. The magnitude and sustainability of the immune response against C2 and the occurrence of a booster effect of infection, an indirect measure of the presence of memory cells, were determined by ELISA, while spectrofluorometry was used to determine and measure the presence of enzyme-inhibiting antibodies. Results Mice immunized with recombinant C2 in TiterMax™, Adjuphos™, purified saponin Quil A™ or Gerbu™ showed the best response according to the evaluation criteria and the latter three were chosen for the cattle vaccination study. The cattle were challenged with T. congolense four and a half months after the last booster. Cattle immunized with recombinant C2 in purified saponin Quil A™ showed the best antibody response according to the measured parameters. Conclusions We identified purified saponin Quil A™ as a good adjuvant for immunizations with C2. The results from this study will be useful in future attempts to develop an effective anti-disease vaccine against African trypanosomosis.

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

Immune oncology, immune responsiveness and the theory of everything.

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Turan, Tolga; Kannan, Deepti; Patel, Maulik; Matthew Barnes, J; Tanlimco, Sonia G; Lu, Rongze; Halliwill, Kyle; Kongpachith, Sarah; Kline, Douglas E; Hendrickx, Wouter; Cesano, Alessandra; Butterfield, Lisa H; Kaufman, Howard L; Hudson, Thomas J; Bedognetti, Davide; Marincola, Francesco; Samayoa, Josue

2018-06-05

Anti-cancer immunotherapy is encountering its own checkpoint. Responses are dramatic and long lasting but occur in a subset of tumors and are largely dependent upon the pre-existing immune contexture of individual cancers. Available data suggest that three landscapes best define the cancer microenvironment: immune-active, immune-deserted and immune-excluded. This trichotomy is observable across most solid tumors (although the frequency of each landscape varies depending on tumor tissue of origin) and is associated with cancer prognosis and response to checkpoint inhibitor therapy (CIT). Various gene signatures (e.g. Immunological Constant of Rejection - ICR and Tumor Inflammation Signature - TIS) that delineate these landscapes have been described by different groups. In an effort to explain the mechanisms of cancer immune responsiveness or resistance to CIT, several models have been proposed that are loosely associated with the three landscapes. Here, we propose a strategy to integrate compelling data from various paradigms into a "Theory of Everything". Founded upon this unified theory, we also propose the creation of a task force led by the Society for Immunotherapy of Cancer (SITC) aimed at systematically addressing salient questions relevant to cancer immune responsiveness and immune evasion. This multidisciplinary effort will encompass aspects of genetics, tumor cell biology, and immunology that are pertinent to the understanding of this multifaceted problem.

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

Previous 60-Co radiation from Paratrygon aiereba mucus induces the production of highly responsive antibodies and a better immune response in mice

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Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Turíbio, Thompson de Oliveira; Rocha, André Moreira; Aires, Raquel da Silva; Jácome, Larissa Barros Silvestre; Spencer, Patrick Jack, E-mail: gabiortegacoelho@usp.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil). Centro de Biotecnologia; Costa, Andrea da; Rodrigues, Jaqueline Pollizeli; Galisteo Júnior, Andrés Jimenez; Andrade Júnior, Heitor Franco de, E-mail: hfandrad@usp.br, E-mail: raquelaires@itpacporto.com.br [Universidade de São Paulo (USP), São Paulo, SP (Brazil). Laboratório de Protozoologia; Seibert, Carla Simone, E-mail: seibertcs@uft.edu.br [Universidade Federal do Tocantins (UFT), Porto Nacional, TO (Brazil)

2017-07-01

Wounds from stinging freshwater stingrays are painful, difficult to heal and cause extensive necrosis and systemic phenomena. The treatment is symptomatic, of low efficiency and there is no therapy, which causes more suffering to the injured. This study aimed to evaluate the immune response induced by the native or irradiated by 60-Co gamma from Paratrygon aiereba mucus. IPEN’s Committee on Ethics in the Use of Animals (n.º126/2013) and lanes captured under license from the Chico Mendes Institute for Biodiversity Conservation (n.º6781-1/2014) approved this research. For the assays, sera from Swiss mice previously immunized against native or irradiated mucus were used. The proliferation of splenic B cells in response to mucus was evaluated by the In Vitro Induced Antibody Production method and serum and splenic cytokines were also quantified. Our data demonstrate that the irradiated mucus of P. aiereba induces greater production of antibodies and more immunological memory in the mice. Spleen cells from animals immunized against irradiated mucus produced IFN-γ, TNF-α and IL-10, and serum TNF-α (immunized group against irradiated mucus) and IL-6 and IL-17 (immunized group against native mucus). The results corroborate the use of ionizing radiation, with production of highly responsive antibodies and better immune response, besides proving that Paratrygon aiereba mucus is capable of stimulating cellular and humoral adaptive immune response, contributing to the continuity of associated investigations. (author)

Previous 60-Co radiation from Paratrygon aiereba mucus induces the production of highly responsive antibodies and a better immune response in mice

International Nuclear Information System (INIS)

Thomazi, Gabriela Ortega Coelho; Alves, Glaucie Jussilane; Turíbio, Thompson de Oliveira; Rocha, André Moreira; Aires, Raquel da Silva; Jácome, Larissa Barros Silvestre; Spencer, Patrick Jack

2017-01-01

Wounds from stinging freshwater stingrays are painful, difficult to heal and cause extensive necrosis and systemic phenomena. The treatment is symptomatic, of low efficiency and there is no therapy, which causes more suffering to the injured. This study aimed to evaluate the immune response induced by the native or irradiated by 60-Co gamma from Paratrygon aiereba mucus. IPEN’s Committee on Ethics in the Use of Animals (n.º126/2013) and lanes captured under license from the Chico Mendes Institute for Biodiversity Conservation (n.º6781-1/2014) approved this research. For the assays, sera from Swiss mice previously immunized against native or irradiated mucus were used. The proliferation of splenic B cells in response to mucus was evaluated by the In Vitro Induced Antibody Production method and serum and splenic cytokines were also quantified. Our data demonstrate that the irradiated mucus of P. aiereba induces greater production of antibodies and more immunological memory in the mice. Spleen cells from animals immunized against irradiated mucus produced IFN-γ, TNF-α and IL-10, and serum TNF-α (immunized group against irradiated mucus) and IL-6 and IL-17 (immunized group against native mucus). The results corroborate the use of ionizing radiation, with production of highly responsive antibodies and better immune response, besides proving that Paratrygon aiereba mucus is capable of stimulating cellular and humoral adaptive immune response, contributing to the continuity of associated investigations. (author)

Short-term and long-term antibody response by mice after immunization against Neisseria meningitidis B or diphtheria toxoid

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G.P. Silva

2013-02-01

Full Text Available Serogroup B Neisseria meningitidis (MenB is a major cause of invasive disease in early childhood worldwide. The only MenB vaccine available in Brazil was produced in Cuba and has shown unsatisfactory efficacy when used to immunize millions of children in Brazil. In the present study, we compared the specific functional antibody responses evoked by the Cuban MenB vaccine with a standard vaccine against diphtheria (DTP: diphtheria, tetanus, pertussis after primary immunization and boosting of mice. The peak of bactericidal and opsonic antibody titers to MenB and of neutralizing antibodies to diphtheria toxoid (DT was reached after triple immunization with the MenB vaccine or DTP vaccine, respectively. However, 4 months after immunization, protective DT antibody levels were present in all DTP-vaccinated mice but in only 20% of the mice immunized against MenB. After 6 months of primary immunization, about 70% of animals still had protective neutralizing DT antibodies, but none had significant bactericidal antibodies to MenB. The booster doses of DTP or MenB vaccines produced a significant antibody recall response, suggesting that both vaccines were able to generate and maintain memory B cells during the period studied (6 months post-triple immunization. Therefore, due to the short duration of serological memory induced by the MenB vaccine (VA-MENGOC-BC® vaccine, its use should be restricted to outbreaks of meningococcal disease.

Immune markers and correlates of protection for vaccine induced immune responses

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Thakur, Aneesh; Pedersen, Lasse Eggers; Jungersen, Gregers

2012-01-01

of an appropriate humoral response currently remain the best validated correlates of protective immunity after vaccination. Despite advancements in the field of immunology over the past few decades currently there are, however, no sufficiently validated immune correlates of vaccine induced protection against......-specific production of interferon-gamma (IFN-γ) has been promoted as a quantitative marker of protective cell-mediated immune responses over the past couple of decades. More recently, however, evidence from several infections has pointed towards the quality of the immune response, measured through increased levels...... of antigen-specific polyfunctional T cells capable of producing a triad of relevant cytokines, as a better correlate of sustained protective immunity against this type of infections. Also the possibilities to measure antigen-specific cytotoxic T cells (CTL) during infection or in response to vaccination...

Enhancement of anamnestic immunospecific antibody response in orally immunized chickens

DEFF Research Database (Denmark)

Mayo, Susan; Carlsson, Hans-Erik; Zagon, Andrea

2008-01-01

Production of immunospecific egg yolk antibodies (IgY antibodies) in egg laying hens through oral immunization is an attractive alternative to conventional antibody production in mammals for economic reasons as well as for animal welfare reasons. Oral immunization results in a systemic humoral...... of the immunization in week 18, demonstrating the presence of memory cells following the two initial oral immunizations. Considering that oral immunization results in approximately ten times lower concentrations of immunospecific antibodies in the egg yolk, compared to traditional subcutaneous immunization schemes...

Persistence of the immune response induced by BCG vaccination

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Blitz Rose

2008-01-01

Full Text Available Abstract Background Although BCG vaccination is recommended in most countries of the world, little is known of the persistence of BCG-induced immune responses. As novel TB vaccines may be given to boost the immunity induced by neonatal BCG vaccination, evidence concerning the persistence of the BCG vaccine-induced response would help inform decisions about when such boosting would be most effective. Methods A randomised control study of UK adolescents was carried out to investigate persistence of BCG immune responses. Adolescents were tested for interferon-gamma (IFN-γ response to Mycobacterium tuberculosis purified protein derivative (M.tb PPD in a whole blood assay before, 3 months, 12 months (n = 148 and 3 years (n = 19 after receiving teenage BCG vaccination or 14 years after receiving infant BCG vaccination (n = 16. Results A gradual reduction in magnitude of response was evident from 3 months to 1 year and from 1 year to 3 years following teenage vaccination, but responses 3 years after vaccination were still on average 6 times higher than before vaccination among vaccinees. Some individuals (11/86; 13% failed to make a detectable antigen-specific response three months after vaccination, or lost the response after 1 (11/86; 13% or 3 (3/19; 16% years. IFN-γ response to Ag85 was measured in a subgroup of adolescents and appeared to be better maintained with no decline from 3 to 12 months. A smaller group of adolescents were tested 14 years after receiving infant BCG vaccination and 13/16 (81% made a detectable IFN-γ response to M.tb PPD 14 years after infant vaccination as compared to 6/16 (38% matched unvaccinated controls (p = 0.012; teenagers vaccinated in infancy were 19 times more likely to make an IFN-γ response of > 500 pg/ml than unvaccinated teenagers. Conclusion BCG vaccination in infancy and adolescence induces immunological memory to mycobacterial antigens that is still present and measurable for at least 14 years in the

Immune activation alters cellular and humoral responses to yellow fever 17D vaccine.

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Muyanja, Enoch; Ssemaganda, Aloysius; Ngauv, Pearline; Cubas, Rafael; Perrin, Helene; Srinivasan, Divya; Canderan, Glenda; Lawson, Benton; Kopycinski, Jakub; Graham, Amanda S; Rowe, Dawne K; Smith, Michaela J; Isern, Sharon; Michael, Scott; Silvestri, Guido; Vanderford, Thomas H; Castro, Erika; Pantaleo, Giuseppe; Singer, Joel; Gillmour, Jill; Kiwanuka, Noah; Nanvubya, Annet; Schmidt, Claudia; Birungi, Josephine; Cox, Josephine; Haddad, Elias K; Kaleebu, Pontiano; Fast, Patricia; Sekaly, Rafick-Pierre; Trautmann, Lydie; Gaucher, Denis

2014-07-01

Defining the parameters that modulate vaccine responses in African populations will be imperative to design effective vaccines for protection against HIV, malaria, tuberculosis, and dengue virus infections. This study aimed to evaluate the contribution of the patient-specific immune microenvironment to the response to the licensed yellow fever vaccine 17D (YF-17D) in an African cohort. We compared responses to YF-17D in 50 volunteers in Entebbe, Uganda, and 50 volunteers in Lausanne, Switzerland. We measured the CD8+ T cell and B cell responses induced by YF-17D and correlated them with immune parameters analyzed by flow cytometry prior to vaccination. We showed that YF-17D-induced CD8+ T cell and B cell responses were substantially lower in immunized individuals from Entebbe compared with immunized individuals from Lausanne. The impaired vaccine response in the Entebbe cohort associated with reduced YF-17D replication. Prior to vaccination, we observed higher frequencies of exhausted and activated NK cells, differentiated T and B cell subsets and proinflammatory monocytes, suggesting an activated immune microenvironment in the Entebbe volunteers. Interestingly, activation of CD8+ T cells and B cells as well as proinflammatory monocytes at baseline negatively correlated with YF-17D-neutralizing antibody titers after vaccination. Additionally, memory T and B cell responses in preimmunized volunteers exhibited reduced persistence in the Entebbe cohort but were boosted by a second vaccination. Together, these results demonstrate that an activated immune microenvironment prior to vaccination impedes efficacy of the YF-17D vaccine in an African cohort and suggest that vaccine regimens may need to be boosted in African populations to achieve efficient immunity. Registration is not required for observational studies. This study was funded by Canada's Global Health Research Initiative, Defense Threat Reduction Agency, National Institute of Allergy and Infectious Diseases

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

Biomarkers of Environmental Enteropathy are Positively Associated with Immune Responses to an Oral Cholera Vaccine in Bangladeshi Children.

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Muhammad Ikhtear Uddin

2016-11-01

Full Text Available Environmental enteropathy (EE is a poorly understood condition that refers to chronic alterations in intestinal permeability, absorption, and inflammation, which mainly affects young children in resource-limited settings. Recently, EE has been linked to suboptimal oral vaccine responses in children, although immunological mechanisms are poorly defined. The objective of this study was to determine host factors associated with immune responses to an oral cholera vaccine (OCV. We measured antibody and memory T cell immune responses to cholera antigens, micronutrient markers in blood, and EE markers in blood and stool from 40 Bangladeshi children aged 3-14 years who received two doses of OCV given 14 days apart. EE markers included stool myeloperoxidase (MPO and alpha anti-trypsin (AAT, and plasma endotoxin core antibody (EndoCab, intestinal fatty acid binding protein (i-FABP, and soluble CD14 (sCD14. We used multiple linear regression analysis with LASSO regularization to identify host factors, including EE markers, micronutrient (nutritional status, age, and HAZ score, predictive for each response of interest. We found stool MPO to be positively associated with IgG antibody responses to the B subunit of cholera toxin (P = 0.03 and IgA responses to LPS (P = 0.02; plasma sCD14 to be positively associated with LPS IgG responses (P = 0.07; plasma i-FABP to be positively associated with LPS IgG responses (P = 0.01 and with memory T cell responses specific to cholera toxin (P = 0.01; stool AAT to be negatively associated with IL-10 (regulatory T cell responses specific to cholera toxin (P = 0.02, and plasma EndoCab to be negatively associated with cholera toxin-specific memory T cell responses (P = 0.02. In summary, in a cohort of children 3-14 years old, we demonstrated that the majority of biomarkers of environmental enteropathy were positively associated with immune responses after vaccination with an OCV.

Memory NK cells: why do they reside in the liver?

OpenAIRE

Jiang, Xiaojun; Chen, Yonglin; Peng, Hui; Tian, Zhigang

2013-01-01

Immune memory is the hallmark of adaptive immunity. However, recent studies have shown that natural killer (NK) cells, key components of the innate immune system, also mediate memory responses in mice and humans. Strikingly, memory NK cells were liver-resident in some models, raising the question as to whether the liver is a special organ for the acquisition of NK cell memory. Here, we review the characteristics of NK cell memory by summarizing recent progress and discuss how the liver may ge...

THE IMPACT OF PERSISTENT HERPESVIRUS INFECTION ON IMMUNITY AND VACCINATION RESPONSE

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Volyanskiy AYu

2016-09-01

outcome of vaccination. The EBV virus remains in memory B cells throughout life. In healthy subjects the EBV remains latent in the latency phase 0 and EBV replication proceeds without production of infectious virions. But the virus can be reactivated in latency phases 1, 2 and 3. The virus reactivation can affect immunity and results in diseases. Chronic fatigue syndrome (CFS is characterized by fatigue, exhaustion and flu-like symptoms. EBV latent reactivation in CFS patients is supported by certain data. In a subset of patients, CFS begins with infectious mononucleosis and enhanced EBV-specific antibody titers have been reported. Also, a profound deficiency in EBV-specific B and T cell memory response was observed in a majority of CFS patients. These data confirmed the EBV virus involvement in the CFS development. Cytokine dysregulation, decreased natural killer cell functioning, the presence of autoantibodies, and a reduced response of T cells to mitogens have been reported in CFS. But if immunity is disturbed in CFS patients, they might have an altered response to vaccination. Herpes viral reactivation has been documented in sepsis. Demonstration of the widespread reactivation of latent herpesviruses in sepsis provides strong evidence that sepsis results in functional immunosuppression. Reactivation of latent viruses may be associated not only with sepsis but with aging as well. Moreover, according to our data herpesvirus reactivation is common in recurrently infected children. These observations highlight the ability of herpesviruses to profoundly impact the host immune function. But the recent publications have shown that persistent herpesvirus infection can be beneficial for the host. The data obtained from the multiple mouse models demonstrate the potential for herpesvirus infection to enhance resistance against a secondary infection. It has been documented that during latent murine cytomegalovirus or murine gammaherpesvirus infection 68 mice are protected against

The impact of immunosenescence on humoral immune response variation after influenza A/H1N1 vaccination in older subjects.

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Iana H Haralambieva

Full Text Available Although influenza causes significant morbidity and mortality in the elderly, the factors underlying the reduced vaccine immunogenicity and efficacy in this age group are not completely understood. Age and immunosenescence factors, and their impact on humoral immunity after influenza vaccination, are of growing interest for the development of better vaccines for the elderly.We assessed associations between age and immunosenescence markers (T cell receptor rearrangement excision circles - TREC content, peripheral white blood cell telomerase - TERT expression and CD28 expression on T cells and influenza A/H1N1 vaccine-induced measures of humoral immunity in 106 older subjects at baseline and three timepoints post-vaccination.TERT activity (TERT mRNA expression was significantly positively correlated with the observed increase in the influenza-specific memory B cell ELISPOT response at Day 28 compared to baseline (p-value=0.025. TREC levels were positively correlated with the baseline and early (Day 3 influenza A/H1N1-specific memory B cell ELISPOT response (p-value=0.042 and p-value=0.035, respectively. The expression and/or expression change of CD28 on CD4+ and/or CD8+ T cells at baseline and Day 3 was positively correlated with the influenza A/H1N1-specific memory B cell ELISPOT response at baseline, Day 28 and Day 75 post-vaccination. In a multivariable analysis, the peak antibody response (HAI and/or VNA at Day 28 was negatively associated with age, the percentage of CD8+CD28 low T cells, IgD+CD27- naïve B cells, and percentage overall CD20- B cells and plasmablasts, measured at Day 3 post-vaccination. The early change in influenza-specific memory B cell ELISPOT response was positively correlated with the observed increase in influenza A/H1N1-specific HAI antibodies at Day 28 and Day 75 relative to baseline (p-value=0.007 and p-value=0.005, respectively.Our data suggest that influenza-specific humoral immunity is significantly influenced by

Functional aspects of the adaptive immune system in arthritis

NARCIS (Netherlands)

Jansen, D.T.S.L.

2017-01-01

The adaptive immune system is the part of the immune system that is highly specific and generates memory resulting in a fast and specific immune response upon a second infection with the same pathogen. However, when this response is specific for a part of the body itself instead of a pathogen,

Population-expression models of immune response

International Nuclear Information System (INIS)

Stromberg, Sean P; Antia, Rustom; Nemenman, Ilya

2013-01-01

The immune response to a pathogen has two basic features. The first is the expansion of a few pathogen-specific cells to form a population large enough to control the pathogen. The second is the process of differentiation of cells from an initial naive phenotype to an effector phenotype which controls the pathogen, and subsequently to a memory phenotype that is maintained and responsible for long-term protection. The expansion and the differentiation have been considered largely independently. Changes in cell populations are typically described using ecologically based ordinary differential equation models. In contrast, differentiation of single cells is studied within systems biology and is frequently modeled by considering changes in gene and protein expression in individual cells. Recent advances in experimental systems biology make available for the first time data to allow the coupling of population and high dimensional expression data of immune cells during infections. Here we describe and develop population-expression models which integrate these two processes into systems biology on the multicellular level. When translated into mathematical equations, these models result in non-conservative, non-local advection-diffusion equations. We describe situations where the population-expression approach can make correct inference from data while previous modeling approaches based on common simplifying assumptions would fail. We also explore how model reduction techniques can be used to build population-expression models, minimizing the complexity of the model while keeping the essential features of the system. While we consider problems in immunology in this paper, we expect population-expression models to be more broadly applicable. (paper)

Secondary immunization generates clonally related antigen-specific plasma cells and memory B cells.

Science.gov (United States)

Frölich, Daniela; Giesecke, Claudia; Mei, Henrik E; Reiter, Karin; Daridon, Capucine; Lipsky, Peter E; Dörner, Thomas

2010-09-01

Rechallenge with T cell-dependent Ags induces memory B cells to re-enter germinal centers (GCs) and undergo further expansion and differentiation into plasma cells (PCs) and secondary memory B cells. It is currently not known whether the expanded population of memory B cells and PCs generated in secondary GCs are clonally related, nor has the extent of proliferation and somatic hypermutation of their precursors been delineated. In this study, after secondary tetanus toxoid (TT) immunization, TT-specific PCs increased 17- to 80-fold on days 6-7, whereas TT-specific memory B cells peaked (delayed) on day 14 with a 2- to 22-fold increase. Molecular analyses of V(H)DJ(H) rearrangements of individual cells revealed no major differences of gene usage and CDR3 length between TT-specific PCs and memory B cells, and both contained extensive evidence of somatic hypermutation with a pattern consistent with GC reactions. This analysis identified clonally related TT-specific memory B cells and PCs. Within clusters of clonally related cells, sequences shared a number of mutations but also could contain additional base pair changes. The data indicate that although following secondary immunization PCs can derive from memory B cells without further somatic hypermutation, in some circumstances, likely within GC reactions, asymmetric mutation can occur. These results suggest that after the fate decision to differentiate into secondary memory B cells or PCs, some committed precursors continue to proliferate and mutate their V(H) genes.

Clay Nanoparticles Elicit Long-Term Immune Responses by Forming Biodegradable Depots for Sustained Antigen Stimulation.

Science.gov (United States)

Chen, Weiyu; Zuo, Huali; Li, Bei; Duan, Chengcheng; Rolfe, Barbara; Zhang, Bing; Mahony, Timothy J; Xu, Zhi Ping

2018-05-01

Nanomaterials have been widely tested as new generation vaccine adjuvants, but few evoke efficient immunoreactions. Clay nanoparticles, for example, layered double hydroxide (LDH) and hectorite (HEC) nanoparticles, have shown their potent adjuvanticity in generating effective and durable immune responses. However, the mechanism by which clay nanoadjuvants stimulate the immune system is not well understood. Here, it is demonstrated that LDH and HEC-antigen complexes form loose agglomerates in culture medium/serum. They also form nodules with loose structures in tissue after subcutaneous injection, where they act as a depot for up to 35 d. More importantly, clay nanoparticles actively and continuously recruit immune cells into the depot for up to one month, and stimulate stronger immune responses than FDA-approved adjuvants, Alum and QuilA. Sustained antigen release is also observed in clay nanoparticle depots, with 50-60% antigen released after 35 d. In contrast, Alum-antigen complexes show minimal antigen release from the depot. Importantly, LDH and HEC are more effective than QuilA and Alum in promoting memory T-cell proliferation. These findings suggest that both clay nanoadjuvants can serve as active vaccine platforms for sustained and potent immune responses. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Virus-specific immune memory at peripheral sites of herpes simplex virus type 2 (HSV-2) infection in guinea pigs.

Science.gov (United States)

Xia, Jingya; Veselenak, Ronald L; Gorder, Summer R; Bourne, Nigel; Milligan, Gregg N

2014-01-01

Despite its importance in modulating HSV-2 pathogenesis, the nature of tissue-resident immune memory to HSV-2 is not completely understood. We used genital HSV-2 infection of guinea pigs to assess the type and location of HSV-specific memory cells at peripheral sites of HSV-2 infection. HSV-specific antibody-secreting cells were readily detected in the spleen, bone marrow, vagina/cervix, lumbosacral sensory ganglia, and spinal cord of previously-infected animals. Memory B cells were detected primarily in the spleen and to a lesser extent in bone marrow but not in the genital tract or neural tissues suggesting that the HSV-specific antibody-secreting cells present at peripheral sites of HSV-2 infection represented persisting populations of plasma cells. The antibody produced by these cells isolated from neural tissues of infected animals was functionally relevant and included antibodies specific for HSV-2 glycoproteins and HSV-2 neutralizing antibodies. A vigorous IFN-γ-secreting T cell response developed in the spleen as well as the sites of HSV-2 infection in the genital tract, lumbosacral ganglia and spinal cord following acute HSV-2 infection. Additionally, populations of HSV-specific tissue-resident memory T cells were maintained at these sites and were readily detected up to 150 days post HSV-2 infection. Unlike the persisting plasma cells, HSV-specific memory T cells were also detected in uterine tissue and cervicothoracic region of the spinal cord and at low levels in the cervicothoracic ganglia. Both HSV-specific CD4+ and CD8+ resident memory cell subsets were maintained long-term in the genital tract and sensory ganglia/spinal cord following HSV-2 infection. Together these data demonstrate the long-term maintenance of both humoral and cellular arms of the adaptive immune response at the sites of HSV-2 latency and virus shedding and highlight the utility of the guinea pig infection model to investigate tissue-resident memory in the setting of HSV-2 latency

Virus-specific immune memory at peripheral sites of herpes simplex virus type 2 (HSV-2 infection in guinea pigs.

Directory of Open Access Journals (Sweden)

Jingya Xia

Full Text Available Despite its importance in modulating HSV-2 pathogenesis, the nature of tissue-resident immune memory to HSV-2 is not completely understood. We used genital HSV-2 infection of guinea pigs to assess the type and location of HSV-specific memory cells at peripheral sites of HSV-2 infection. HSV-specific antibody-secreting cells were readily detected in the spleen, bone marrow, vagina/cervix, lumbosacral sensory ganglia, and spinal cord of previously-infected animals. Memory B cells were detected primarily in the spleen and to a lesser extent in bone marrow but not in the genital tract or neural tissues suggesting that the HSV-specific antibody-secreting cells present at peripheral sites of HSV-2 infection represented persisting populations of plasma cells. The antibody produced by these cells isolated from neural tissues of infected animals was functionally relevant and included antibodies specific for HSV-2 glycoproteins and HSV-2 neutralizing antibodies. A vigorous IFN-γ-secreting T cell response developed in the spleen as well as the sites of HSV-2 infection in the genital tract, lumbosacral ganglia and spinal cord following acute HSV-2 infection. Additionally, populations of HSV-specific tissue-resident memory T cells were maintained at these sites and were readily detected up to 150 days post HSV-2 infection. Unlike the persisting plasma cells, HSV-specific memory T cells were also detected in uterine tissue and cervicothoracic region of the spinal cord and at low levels in the cervicothoracic ganglia. Both HSV-specific CD4+ and CD8+ resident memory cell subsets were maintained long-term in the genital tract and sensory ganglia/spinal cord following HSV-2 infection. Together these data demonstrate the long-term maintenance of both humoral and cellular arms of the adaptive immune response at the sites of HSV-2 latency and virus shedding and highlight the utility of the guinea pig infection model to investigate tissue-resident memory in the

Altered Cellular Metabolism Drives Trained Immunity.

Science.gov (United States)

Sohrabi, Yahya; Godfrey, Rinesh; Findeisen, Hannes M

2018-04-04

Exposing innate immune cells to an initial insult induces a long-term proinflammatory response due to metabolic and epigenetic alterations which encompass an emerging new concept called trained immunity. Recent studies provide novel insights into mechanisms centered on metabolic reprogramming which induce innate immune memory in hematopoietic stem cells and monocytes. Copyright © 2018 Elsevier Ltd. All rights reserved.

Pertussis vaccinations in Dutch children: memory immune responses

NARCIS (Netherlands)

Hendrikx, L.H.

2011-01-01

Despite high pertussis vaccination coverage, pertussis is reemerging in the Netherlands since 1996. In attempt to improve protection against whooping cough, two major changes in the national immunization program have been made; the introduction of a preschool booster vaccination in children 4 years

Antimicrobial peptides in innate immune responses

DEFF Research Database (Denmark)

Sorensen, O.E.; Borregaard, N.; Cole, A.M.

2008-01-01

Antimicrobial peptides (AMPs) are ancient effector molecules in the innate immune response of eukaryotes. These peptides are important for the antimicrobial efficacy of phagocytes and for the innate immune response mounted by epithelia of humans and other mammals. AMPs are generated either by de...... novo synthesis or by proteolytic cleavage from antimicrobially inactive proproteins. Studies of human diseases and animal studies have given important clues to the in vivo role of AMPs. It is now evident that dysregulation of the generation of AMPs in innate immune responses plays a role in certain...

Gel-Trapped Lymphorganogenic Chemokines Trigger Artificial Tertiary Lymphoid Organs and Mount Adaptive Immune Responses In Vivo.

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Kobayashi, Yuka; Watanabe, Takeshi

2016-01-01

We previously generated artificial lymph node-like tertiary lymphoid organs (artTLOs) in mice using lymphotoxin α-expressing stromal cells. Here, we show the construction of transplantable and functional artTLOs by applying soluble factors trapped in slow-releasing gels in the absence of lymphoid tissue organizer stromal cells. The resultant artTLOs were easily removable, transplantable, and were capable of attracting memory B and T cells. Importantly, artTLOs induced a powerful antigen-specific secondary immune response, which was particularly pronounced in immune-compromised hosts. Synthesis of functionally stable immune tissues/organs like those described here may be a first step to eventually develop immune system-based therapeutics. Although much needs to be learned from the precise mechanisms of action, they may offer ways in the future to reestablish immune functions to overcome hitherto untreatable diseases, including severe infection, cancer, autoimmune diseases, and various forms of immune deficiencies, including immune-senescence during aging.

Gel-trapped lymphorganogenic chemokines trigger artificial tertiary lymphoid organs and mount adaptive immune responses in vivo

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Takeshi Watanabe

2016-08-01

Full Text Available We previously generated artificial lymph node-like tertiary lymphoid organs (artTLOs in mice using lymphotoxin α-expressing stromal cells. Here, we show the construction of transplantable and functional artTLOs by applying soluble factors trapped in slow-releasing gels in the absence of lymphoid tissue organizer- (LTo stromal cells. The resultant artTLOs were easily removable, transplantable, and were capable of attracting memory B and T cells. Importantly, artTLOs induced a powerful antigen-specific secondary immune response, which was particularly pronounced in immune-compromised hosts. Synthesis of functionally stable immune tissues/organs like those described here may be a first step to eventually develop immune system-based therapeutics. Although much needs to be learned from the precise mechanisms of action, they may offer ways in the future to reestablish immune functions to overcome hitherto untreatable diseases including severe infection, cancer, autoimmune diseases, and various forms of immune deficiencies including immune-senescence during aging.

CD27 instructs CD4+ T cells to provide help for the memory CD8+ T cell response after protein immunization

NARCIS (Netherlands)

Xiao, Yanling; Peperzak, Victor; Keller, Anna M.; Borst, Jannie

2008-01-01

For optimal quality, memory CD8(+) T cells require CD4(+) T cell help. We have examined whether CD4(+) T cells require CD27 to deliver this help, in a model of intranasal OVA protein immunization. CD27 deficiency reduced the capacity of CD4(+) T cells to support Ag-specific CD8(+) T cell

Immune response to H pylori

Science.gov (United States)

Suarez, Giovanni; Reyes, Victor E; Beswick, Ellen J

2006-01-01

The gastric mucosa separates the underlying tissue from the vast array of antigens that traffic through the stomach lumen. While the extreme pH of this environment is essential in aiding the activation of enzymes and food digestion, it also renders the gastric epithelium free from bacterial colonization, with the exception of one important human pathogen, H pylori. This bacterium has developed mechanisms to survive the harsh environment of the stomach, actively move through the mucosal layer, attach to the epithelium, evade immune responses, and achieve persistent colonization. While a hallmark of this infection is a marked inflammatory response with the infiltration of various immune cells into the infected gastric mucosa, the host immune response is unable to clear the infection and may actually contribute to the associated pathogenesis. Here, we review the host responses involved during infection with H pylori and how they are influenced by this bacterium. PMID:17007009

Impact of infant and preschool pertussis vaccinations on memory B-cell responses in children at 4 years of age.

Science.gov (United States)

Hendrikx, Lotte H; de Rond, Lia G H; Oztürk, Kemal; Veenhoven, Reinier H; Sanders, Elisabeth A M; Berbers, Guy A M; Buisman, Anne-Marie

2011-08-05

Whooping cough, caused by Bordetella pertussis, is reemerging in the vaccinated population. Antibody levels to pertussis antigens wane rapidly after both whole-cell (wP) and acellular pertussis (aP) vaccination and protection may largely depend on long-term B- and T-cell immunity. We studied the effect of wP and aP infant priming at 2, 3, 4 and 11 months according to the Dutch immunization program on pertussis-specific memory B-cell responses before and after a booster vaccination with either a high- or low-pertussis dose vaccine at 4 years of age. Purified B-cells were characterized by FACS-analysis and after polyclonal stimulation, memory B-cells were detected by ELISPOT-assays specific for pertussis toxin, filamentous haemagglutinin and pertactin. Before and after the booster, higher memory B-cell responses were measured in aP primed children compared with wP primed children. In contrast with antibody levels, no dose-effect was observed on the numbers of memory B-cell responses. In aP primed children a fifth high-dose aP vaccination tended to induce even lower memory B-cell responses than a low-dose aP booster. In both wP and aP primed children, the number of memory B-cells increased after the booster and correlated with the pertussis-specific antibody concentrations and observed affinity maturation. This study indicates that aP vaccinations in the first year of life induce higher pertussis-specific memory B-cell responses in children 4 years of age compared with Dutch wP primary vaccinations. Since infant aP vaccinations have improved protection against whooping cough in children despite waning antibody levels, this suggests that an enhanced memory B-cell pool induction may have an important role in protection. However, the pertussis-dose of the preschool booster needs to be considered depending on the vaccine used for priming to optimize long-term protection against whooping cough. Copyright © 2011 Elsevier Ltd. All rights reserved.

Entirely Carbohydrate-Based Vaccines: An Emerging Field for Specific and Selective Immune Responses

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Sharmeen Nishat

2016-05-01

Full Text Available Carbohydrates are regarded as promising targets for vaccine development against infectious disease because cell surface glycans on many infectious agents are attributed to playing an important role in pathogenesis. In addition, oncogenic transformation of normal cells, in many cases, is associated with aberrant glycosylation of the cell surface glycan generating tumor associated carbohydrate antigens (TACAs. Technological advances in glycobiology have added a new dimension to immunotherapy when considering carbohydrates as key targets in developing safe and effective vaccines to combat cancer, bacterial infections, viral infections, etc. Many consider effective vaccines induce T-cell dependent immunity with satisfactory levels of immunological memory that preclude recurrence. Unfortunately, carbohydrates alone are poorly immunogenic as they do not bind strongly to the MHCII complex and thus fail to elicit T-cell immunity. To increase immunogenicity, carbohydrates have been conjugated to carrier proteins, which sometimes can impede carbohydrate specific immunity as peptide-based immune responses can negate antibodies directed at the targeted carbohydrate antigens. To overcome many challenges in using carbohydrate-based vaccine design and development approaches targeting cancer and other diseases, zwitterionic polysaccharides (ZPSs, isolated from the capsule of commensal anaerobic bacteria, will be discussed as promising carriers of carbohydrate antigens to achieve desired immunological responses.

Memory NK cells: why do they reside in the liver?

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Jiang, Xiaojun; Chen, Yonglin; Peng, Hui; Tian, Zhigang

2013-05-01

Immune memory is the hallmark of adaptive immunity. However, recent studies have shown that natural killer (NK) cells, key components of the innate immune system, also mediate memory responses in mice and humans. Strikingly, memory NK cells were liver-resident in some models, raising the question as to whether the liver is a special organ for the acquisition of NK cell memory. Here, we review the characteristics of NK cell memory by summarizing recent progress and discuss how the liver may generate both the initiation and the recall phase of memory. We propose that the liver may have unique precursors for memory NK cells, which are developmentally distinct from NK cells derived from bone marrow.

Defence mechanisms and immune evasion in the interplay between the humane immune system and Plasmodium falciparum

DEFF Research Database (Denmark)

Theander, T G

1992-01-01

Immunity to P. falciparum malaria is developed as a result of long term exposure to the parasite and depends on immunological memory. The key directors in immune recognition and regulation of the immunological responses are the T-cells. It seems reasonable to propose that immunity is acquired when...... with development of immunity. Several mechanisms seem to be operating. 1) Induction of the immune response to some macromolecules is avoided because the parasites are living inside host cells during part of their life cycle, and the reaction to other molecules is apparently avoided by mimicry of host molecules. 2...

Altered Memory T-Cell Responses to Bacillus Calmette-Guerin and Tetanus Toxoid Vaccination and Altered Cytokine Responses to Polyclonal Stimulation in HIV-Exposed Uninfected Kenyan Infants.

Science.gov (United States)

Garcia-Knight, Miguel A; Nduati, Eunice; Hassan, Amin S; Gambo, Faith; Odera, Dennis; Etyang, Timothy J; Hajj, Nassim J; Berkley, James Alexander; Urban, Britta C; Rowland-Jones, Sarah L

2015-01-01

Implementation of successful prevention of mother-to-child transmission of HIV strategies has resulted in an increased population of HIV-exposed uninfected (HEU) infants. HEU infants have higher rates of morbidity and mortality than HIV-unexposed (HU) infants. Numerous factors may contribute to poor health in HEU infants including immunological alterations. The present study assessed T-cell phenotype and function in HEU infants with a focus on memory Th1 responses to vaccination. We compared cross-sectionally selected parameters at 3 and 12 months of age in HIV-exposed (n = 42) and HU (n = 28) Kenyan infants. We measured ex vivo activated and bulk memory CD4 and CD8 T-cells and regulatory T-cells by flow cytometry. In addition, we measured the magnitude, quality and memory phenotype of antigen-specific T-cell responses to Bacillus Calmette-Guerin and Tetanus Toxoid vaccine antigens, and the magnitude and quality of the T cell response following polyclonal stimulation with staphylococcal enterotoxin B. Finally, the influence of maternal disease markers on the immunological parameters measured was assessed in HEU infants. Few perturbations were detected in ex vivo T-cell subsets, though amongst HEU infants maternal HIV viral load positively correlated with CD8 T cell immune activation at 12 months. Conversely, we observed age-dependent differences in the magnitude and polyfunctionality of IL-2 and TNF-α responses to vaccine antigens particularly in Th1 cells. These changes mirrored those seen following polyclonal stimulation, where at 3 months, cytokine responses were higher in HEU infants compared to HU infants, and at 12 months, HEU infant cytokine responses were consistently lower than those seen in HU infants. Finally, reduced effector memory Th1 responses to vaccine antigens were observed in HEU infants at 3 and 12 months and higher central memory Th1 responses to M. tuberculosis antigens were observed at 3 months only. Long-term monitoring of vaccine efficacy

Altered Memory T-Cell Responses to Bacillus Calmette-Guerin and Tetanus Toxoid Vaccination and Altered Cytokine Responses to Polyclonal Stimulation in HIV-Exposed Uninfected Kenyan Infants.

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Miguel A Garcia-Knight

Full Text Available Implementation of successful prevention of mother-to-child transmission of HIV strategies has resulted in an increased population of HIV-exposed uninfected (HEU infants. HEU infants have higher rates of morbidity and mortality than HIV-unexposed (HU infants. Numerous factors may contribute to poor health in HEU infants including immunological alterations. The present study assessed T-cell phenotype and function in HEU infants with a focus on memory Th1 responses to vaccination. We compared cross-sectionally selected parameters at 3 and 12 months of age in HIV-exposed (n = 42 and HU (n = 28 Kenyan infants. We measured ex vivo activated and bulk memory CD4 and CD8 T-cells and regulatory T-cells by flow cytometry. In addition, we measured the magnitude, quality and memory phenotype of antigen-specific T-cell responses to Bacillus Calmette-Guerin and Tetanus Toxoid vaccine antigens, and the magnitude and quality of the T cell response following polyclonal stimulation with staphylococcal enterotoxin B. Finally, the influence of maternal disease markers on the immunological parameters measured was assessed in HEU infants. Few perturbations were detected in ex vivo T-cell subsets, though amongst HEU infants maternal HIV viral load positively correlated with CD8 T cell immune activation at 12 months. Conversely, we observed age-dependent differences in the magnitude and polyfunctionality of IL-2 and TNF-α responses to vaccine antigens particularly in Th1 cells. These changes mirrored those seen following polyclonal stimulation, where at 3 months, cytokine responses were higher in HEU infants compared to HU infants, and at 12 months, HEU infant cytokine responses were consistently lower than those seen in HU infants. Finally, reduced effector memory Th1 responses to vaccine antigens were observed in HEU infants at 3 and 12 months and higher central memory Th1 responses to M. tuberculosis antigens were observed at 3 months only. Long-term monitoring of

Manipulations of the immune response in the chicken

International Nuclear Information System (INIS)

Bixler, G.S. Jr.

1978-01-01

The chicken with its dissociation of immune responses in cell-mediated immunity, dependent on the thymus, and humoral immunity, dependent on the bursa of Fabricius, provides a unique model for studying the two components of the immune system. While there are methods of obtaining selective, profound deficiency of humoral immunity, in this species, methods for obtaining a consistent, profound selective deficiency of cell-mediated immunity have been lacking. Oxisuran, 2[(methylsulfinyl)acetal] pyridine, has been reported to have the unique ability to differentially suppress cell-mediated immunity in several species of mammals without a concomitant reduction in antibody forming capacity. The effect of this compound on two parameters of cell-mediated immune responses in chickens was investigated. In further attempts to create a deficiency of both cell-mediated and humoral immunity, the effects of a combination of cyclophosphamide treatment and x-irradiation early in life on immune responses were studied

Cross-serotype immunity induced by immunization with a conserved rhinovirus capsid protein.

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Nicholas Glanville

Full Text Available Human rhinovirus (RV infections are the principle cause of common colds and precipitate asthma and COPD exacerbations. There is currently no RV vaccine, largely due to the existence of ∼150 strains. We aimed to define highly conserved areas of the RV proteome and test their usefulness as candidate antigens for a broadly cross-reactive vaccine, using a mouse infection model. Regions of the VP0 (VP4+VP2 capsid protein were identified as having high homology across RVs. Immunization with a recombinant VP0 combined with a Th1 promoting adjuvant induced systemic, antigen specific, cross-serotype, cellular and humoral immune responses. Similar cross-reactive responses were observed in the lungs of immunized mice after infection with heterologous RV strains. Immunization enhanced the generation of heterosubtypic neutralizing antibodies and lung memory T cells, and caused more rapid virus clearance. Conserved domains of the RV capsid therefore induce cross-reactive immune responses and represent candidates for a subunit RV vaccine.

Experimental Ascaris suum infection in the pig: protective memory response after three immunizations and effect of intestinal adult worm population

DEFF Research Database (Denmark)

Jungersen, Gregers; Eriksen, Lis; Roepstorff, Allan

1999-01-01

The protective immune response to larval migration in pigs, with or without adult intestinal worm populations, 10 weeks after 3 weekly Ascaris suum inoculations, was studied in 45 pigs. Controlled adult worm populations were achieved by oral transfer of 10 adult worms to previously immunized pigs...... after anthelmintic drenching. A significant reduction in larval recovery from lungs on day 7, and small intestine on day 14, was observed in immunized pigs compared with previously uninfected control pigs after challenge inoculation. The strong anamnestic response to larval migration was characterized...

The Immune Response of Maternally Immune Chicks to Vaccination ...

African Journals Online (AJOL)

The Immune Response of Maternally Immune Chicks to Vaccination with Newcastle Disease Virus. ... G A El-Tayeb, M Y El-Ttegani, I E Hajer, M A Mohammed ... This study was conducted to determine the persistence of maternally derived antibodies (MDA) to Newcastle disease virus (NDV) in newly hatched chicks and the ...

Gastrointestinal immune responses in HIV infected subjects

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LRR Castello-Branco

1996-06-01

Full Text Available The gut associated lymphoid tissue is responsible for specific responses to intestinal antigens. During HIV infection, mucosal immune deficiency may account for the gastrointestinal infections. In this review we describe the humoral and cellular mucosal immune responses in normal and HIV-infected subjects.

A Systems Vaccinology Approach Reveals Temporal Transcriptomic Changes of Immune Responses to the Yellow Fever 17D Vaccine.

Science.gov (United States)

Hou, Jue; Wang, Shuhui; Jia, Manxue; Li, Dan; Liu, Ying; Li, Zhengpeng; Zhu, Hong; Xu, Huifang; Sun, Meiping; Lu, Li; Zhou, Zhinan; Peng, Hong; Zhang, Qichen; Fu, Shihong; Liang, Guodong; Yao, Lena; Yu, Xuesong; Carpp, Lindsay N; Huang, Yunda; McElrath, Julie; Self, Steve; Shao, Yiming

2017-08-15

In this study, we used a systems vaccinology approach to identify temporal changes in immune response signatures to the yellow fever (YF)-17D vaccine, with the aim of comprehensively characterizing immune responses associated with protective immunity. We conducted a cohort study in which 21 healthy subjects in China were administered one dose of the YF-17D vaccine; PBMCs were collected at 0 h and then at 4 h and days 1, 2, 3, 5, 7, 14, 28, 84, and 168 postvaccination, and analyzed by transcriptional profiling and immunological assays. At 4 h postvaccination, genes associated with innate cell differentiation and cytokine pathways were dramatically downregulated, whereas receptor genes were upregulated, compared with their baseline levels at 0 h. Immune response pathways were primarily upregulated on days 5 and 7, accompanied by the upregulation of the transcriptional factors JUP, STAT1, and EIF2AK2. We also observed robust activation of innate immunity within 2 d postvaccination and a durable adaptive response, as assessed by transcriptional profiling. Coexpression network analysis indicated that lysosome activity and lymphocyte proliferation were associated with dendritic cell (DC) and CD4 + T cell responses; FGL2, NFAM1, CCR1, and TNFSF13B were involved in these associations. Moreover, individuals who were baseline-seropositive for Abs against another flavivirus exhibited significantly impaired DC, NK cell, and T cell function in response to YF-17D vaccination. Overall, our findings indicate that YF-17D vaccination induces a prompt innate immune response and DC activation, a robust Ag-specific T cell response, and a persistent B cell/memory B cell response. Copyright © 2017 by The American Association of Immunologists, Inc.

Memory control by the B cell antigen receptor.

Science.gov (United States)

Engels, Niklas; Wienands, Jürgen

2018-05-01

The generation of memory B cells (MBCs) that have undergone immunoglobulin class switching from IgM, which dominates primary antibody responses, to other immunoglobulin isoforms is a hallmark of immune memory. Hence, humoral immunological memory is characterized by the presence of serum immunoglobulins of IgG subtypes known as the γ-globulin fraction of blood plasma proteins. These antibodies reflect the antigen experience of B lymphocytes and their repeated triggering. In fact, efficient protection against a previously encountered pathogen is critically linked to the production of pathogen-specific IgG molecules even in those cases where the primary immune response required cellular immunity, for example, T cell-mediated clearance of intracellular pathogens such as viruses. Besides IgG, also IgA and IgE can provide humoral immunity depending on the microbe's nature and infection route. The molecular mechanisms underlying the preponderance of switched immunoglobulin isotypes during memory antibody responses are a matter of active and controversial debate. Here, we summarize the phenotypic characteristics of distinct MBC subpopulations and discuss the decisive roles of different B cell antigen receptor isotypes for the functional traits of class-switched B cell populations. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Early nutrition and immunity - progress and perspectives

NARCIS (Netherlands)

Calder, Philip C.; Krauss-Etschmann, Susanne; de Jong, Esther C.; Dupont, Christophe; Frick, Julia-Stefanie; Frokiaer, Hanne; Heinrich, Joachim; Garn, Holger; Koletzko, Sibylle; Lack, Gideon; Mattelio, Gianluca; Renz, Harald; Sangild, Per T.; Schrezenmeir, Jürgen; Stulnig, Thomas M.; Thymann, Thomas; Wold, Agnes E.; Koletzko, Berthold

2006-01-01

The immune system exists to protect the host against pathogenic organisms and highly complex pathways of recognition, response, elimination and memory have evolved in order to fulfil this role. The immune system also acts to ensure tolerance to 'self', to food and other environmental components, and

Pandemics and immune memory in the noisy Penna model

Science.gov (United States)

Cebrat, Stanisław; Bonkowska, Katarzyna; Biecek, Przemysław

2007-06-01

In the noisy Penna model of ageing, instead of counting the number of defective loci which eventually kill an individual, the noise describing the health status of individuals is introduced. This white noise is composed of two components: the environmental one and the personal one. If the sum of both trespasses the limit set for the individuals homeodynamics the individual dies. The energy of personal fluctuations depends on the number of defective loci expressed in the individuals genome. Environmental fluctuations, the same for all individuals can include some signals, corresponding to the exposition to pathogens which could be dangerous for a fraction of the organisms. Personal noise and the component of random environmental fluctuations, when superimposed on the signal can be life threatening if they are stronger than the limit set for individuals homeodynamics. Nevertheless, some organisms survive the period of dangerous signal and they may remember the signal in the future, like antigens are remembered by our immune systems. Unfortunately, this memory weakens with time and, even worse, some additional defective genes are switched on during the ageing. If the same pathogens (signals) emerge during the lifespan of the population, a fraction of the population could remember it and could respond by increasing the resistance to it. Again, unfortunately for some individuals, their memory could be too weak and their own health status has worsened due to the accumulated mutations, they have to die. Though, a fraction of individuals can survive the pandemics due to the immune memory, but a fraction of population has no such a memory because they were born after the last pandemic or they didnt notice this pandemic. Our simple model, by implementing the noise instead of deterministic threshold of genetic defects, describes how the impact of pandemics on populations depends on the time which elapsed between the two incidents and how the different age groups of

Multiple myeloma patients in long-term complete response after autologous stem cell transplantation express a particular immune signature with potential prognostic implication.

Science.gov (United States)

Arteche-López, A; Kreutzman, A; Alegre, A; Sanz Martín, P; Aguado, B; González-Pardo, M; Espiño, M; Villar, L M; García Belmonte, D; de la Cámara, R; Muñoz-Calleja, C

2017-06-01

The proportion of multiple myeloma patients in long-term complete response (LTCR-MM) for more than 6 years after autologous stem cell transplantation (ASCT) is small. To evaluate whether this LTCR is associated with a particular immune signature, peripheral blood samples from 13 LTCR-MM after ASCT and healthy blood donors (HBD) were analysed. Subpopulations of T-cells (naïve, effector, central memory and regulatory), B-cells (naïve, marginal zone-like, class-switched memory, transitional and plasmablasts) and NK-cells expressing inhibitory and activating receptors were quantified by multiparametric flow cytometry (MFC). Heavy/light chains (HLC) were quantified by nephelometry. The percentage of CD4 + T-cells was lower in patients, whereas an increment in the percentage of CD4 + and CD8 + effector memory T-cells was associated with the LTCR. Regulatory T-cells and NK-cells were similar in both groups but a particular redistribution of inhibitory and activating receptors in NK-cells were found in patients. Regarding B-cells, an increase in naïve cells and a corresponding reduction in marginal zone-like and class-switched memory B-cells was observed. The HLC values were normal. Our results suggest that LTCR-MM patients express a particular immune signature, which probably reflects a 'high quality' immune reconstitution that could exert a competent anti-tumor immunological surveillance along with a recovery of the humoral immunity.

Immune Response to Lipoproteins in Atherosclerosis

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Sonia Samson

2012-01-01

Full Text Available Atherosclerosis, the underlying cause of cardiovascular disease, is characterized by chronic inflammation and altered immune response. Cholesterol is a well-known risk factor associated with the development of cardiovascular diseases. Elevated serum cholesterol is unique because it can lead to development of atherosclerosis in animals and humans even in the absence of other risk factors. Modifications of low-density lipoproteins mediated by oxidation, enzymatic degradation, and aggregation result in changes in their function and activate both innate and adaptive immune system. Oxidized low-density lipoprotein (LDL has been identified as one of the most important autoantigens in atherosclerosis. This escape from self-tolerance is dependent on the formation of oxidized phospholipids. The emerging understanding of the importance of immune responses against oxidized LDL in atherosclerosis has focused attention on the possibility of development of novel therapy for atherosclerosis. This review provides an overview of immune response to lipoproteins and the fascinating possibility of developing an immunomodulatory therapy for atherosclerosis.

Cholinergic Modulation of Type 2 Immune Responses

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Goele Bosmans

2017-12-01

Full Text Available In recent years, the bidirectional relationship between the nervous and immune system has become increasingly clear, and its role in both homeostasis and inflammation has been well documented over the years. Since the introduction of the cholinergic anti-inflammatory pathway, there has been an increased interest in parasympathetic regulation of both innate and adaptive immune responses, including T helper 2 responses. Increasing evidence has been emerging suggesting a role for the parasympathetic nervous system in the pathophysiology of allergic diseases, including allergic rhinitis, asthma, food allergy, and atopic dermatitis. In this review, we will highlight the role of cholinergic modulation by both nicotinic and muscarinic receptors in several key aspects of the allergic inflammatory response, including barrier function, innate and adaptive immune responses, and effector cells responses. A better understanding of these cholinergic processes mediating key aspects of type 2 immune disorders might lead to novel therapeutic approaches to treat allergic diseases.

Memory and Specificity in the Insect Immune System: Current Perspectives and Future Challenges

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Dustin Cooper

2017-05-01

Full Text Available The immune response of a host to a pathogen is typically described as either innate or adaptive. The innate form of the immune response is conserved across all organisms, including insects. Previous and recent research has focused on the nature of the insect immune system and the results imply that the innate immune response of insects is more robust and specific than previously thought. Priming of the insect innate immune system involves the exposure of insects to dead or a sublethal dose of microbes in order to elicit an initial response. Comparing subsequent infections in primed insects to non-primed individuals indicates that the insect innate immune response may possess some of the qualities of an adaptive immune system. Although some studies demonstrate that the protective effects of priming are due to a “loitering” innate immune response, others have presented more convincing elements of adaptivity. While an immune mechanism capable of producing the same degree of recognition specificity as seen in vertebrates has yet to be discovered in insects, a few interesting cases have been identified and discussed.

Long-lasting immune responses 4 years after GAD-alum treatment in children with type 1 diabetes.

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Stina Axelsson

Full Text Available A phase II clinical trial with glutamic acid decarboxylase (GAD 65 formulated with aluminium hydroxide (GAD-alum has shown efficacy in preserving residual insulin secretion in children and adolescents with recent-onset type 1 diabetes (T1D. We have performed a 4-year follow-up study of 59 of the original 70 patients to investigate long-term cellular and humoral immune responses after GAD-alum-treatment. Peripheral blood mononuclear cells (PBMC were stimulated in vitro with GAD(65. Frequencies of naïve, central and effector memory CD4+ and CD8+ T cells were measured, together with cytokine secretion, proliferation, gene expression and serum GAD(65 autoantibody (GADA levels. We here show that GAD-alum-treated patients display increased memory T-cell frequencies and prompt T-cell activation upon in vitro stimulation with GAD(65, but not with control antigens, compared with placebo subjects. GAD(65-induced T-cell activation was accompanied by secretion of T helper (Th 1, Th2 and T regulatory cytokines and by induction of T-cell inhibitory pathways. Moreover, post-treatment serum GADA titres remained persistently increased in the GAD-alum arm, but did not inhibit GAD(65 enzymatic activity. In conclusion, memory T- and B-cell responses persist 4 years after GAD-alum-treatment. In parallel to a GAD(65-induced T-cell activation, our results show induction of T-cell inhibitory pathways important for regulating the GAD(65 immunity.

Relationship between Humoral Immune Responses against HPV16, HPV18, HPV31 and HPV45 in 12-15 Year Old Girls Receiving Cervarix® or Gardasil® Vaccine.

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Anna Godi

Full Text Available Human papillomavirus (HPV vaccines confer protection against the oncogenic genotypes HPV16 and HPV18 through the generation of type-specific neutralizing antibodies raised against virus-like particles (VLP representing these genotypes. The vaccines also confer a degree of cross-protection against HPV31 and HPV45, which are genetically-related to the vaccine types HPV16 and HPV18, respectively, although the mechanism is less certain. There are a number of humoral immune measures that have been examined in relation to the HPV vaccines, including VLP binding, pseudovirus neutralization and the enumeration of memory B cells. While the specificity of responses generated against the vaccine genotypes are fairly well studied, the relationship between these measures in relation to non-vaccine genotypes is less certain.We carried out a comparative study of these immune measures against vaccine and non-vaccine genotypes using samples collected from 12-15 year old girls following immunization with three doses of either Cervarix® or Gardasil® HPV vaccine.The relationship between neutralizing and binding antibody titers and HPV-specific memory B cell levels for the vaccine genotypes, HPV16 and HPV18, were very good. The proportion of responders approached 100% for both vaccines while the magnitude of these responses induced by Cervarix® were generally higher than those following Gardasil® immunization. A similar pattern was found for the non-vaccine genotype HPV31, albeit at a lower magnitude compared to its genetically-related vaccine genotype, HPV16. However, both the enumeration of memory B cells and VLP binding responses against HPV45 were poorly related to its neutralizing antibody responses. Purified IgG derived from memory B cells demonstrated specificities similar to those found in the serum, including the capacity to neutralize HPV pseudoviruses.These data suggest that pseudovirus neutralization should be used as the preferred humoral immune

Fine-Needle Aspiration Biopsy of the Lymph Node: A Novel Tool for the Monitoring of Immune Responses after Skin Antigen Delivery.

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Tatovic, Danijela; Young, Philippa; Kochba, Efrat; Levin, Yotam; Wong, F Susan; Dayan, Colin M

2015-07-01

Assessment of immune responses in lymph nodes (LNs) is routine in animals, but rarely done in humans. We have applied minimally invasive ultrasound-guided fine-needle aspiration of the LN to a before-and-after study of the immune response to intradermally delivered Ag in healthy volunteers (n = 25). By comparison with PBMCs from the same individual, LN cells (LNCs) were characterized by reduced numbers of effector memory cells, especially CD8(+) TEMRA cells (3.37 ± 1.93 in LNCs versus 22.53 ± 7.65 in PBMCs; p = 0.01) and a marked increased in CD69 expression (27.67 ± 7.49 versus 3.49 ± 2.62%, LNCs and PBMCs, respectively; p < 0.0001). At baseline, there was a striking absence of IFN-γ ELISPOT responses to recall Ags (purified protein derivative, Tetanus toxoid, or flu/EBV/CMV viral mix) in LN, despite strong responses in the peripheral blood. However, 48 h after tuberculin purified protein derivative administration in the ipsilateral forearm resulting in a positive skin reaction, a clear increase in IFN-γ ELISPOT counts was seen in the draining LN but not in PBMCs. This response was lost by 5 d. These data suggest that the low levels of effector memory cells in the LN may explain the low background of baseline ELISPOT responses in LNs as compared with PBMCs, and the appearance of a response after 48 h is likely to represent migration of effector memory cells from the skin to the LN. Hence, it appears that the combination of intradermal Ag administration and draining LN sampling can be used as a sensitive method to probe the effector memory T cell repertoire in the skin. Copyright © 2015 by The American Association of Immunologists, Inc.

The breadth, but not the magnitude, of circulating memory B cell responses to P. falciparum increases with age/exposure in an area of low transmission.

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Sarah I Nogaro

Full Text Available Malaria caused by Plasmodium falciparum remains a major cause of death in sub-Saharan Africa. Immunity against symptoms of malaria requires repeated exposure, suggesting either that the parasite is poorly immunogenic or that the development of effective immune responses to malaria may be impaired.We carried out two age-stratified cross-sectional surveys of anti-malarial humoral immune responses in a Gambian village where P. falciparum malaria transmission is low and sporadic. Circulating antibodies and memory B cells (MBC to four malarial antigens were measured using ELISA and cultured B cell ELISpot.The proportion of individuals with malaria-specific MBC and antibodies, and the average number of antigens recognised by each individual, increased with age but the magnitude of these responses did not. Malaria-specific antibody levels did not correlate with either the prevalence or median number of MBC, indicating that these two assays are measuring different aspects of the humoral immune response. Among those with immunological evidence of malaria exposure (defined as a positive response to at least one malarial antigen either by ELISA or ELISPOT, the median number of malaria-specific MBC was similar to median numbers of diphtheria-specific MBC, suggesting that the circulating memory cell pool for malaria antigens is of similar size to that for other antigens.

Poly-functional and long-lasting anticancer immune response elicited by a safe attenuated Pseudomonas aeruginosa vector for antigens delivery

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Xavier Chauchet

2016-01-01

Full Text Available Live-attenuated bacterial vectors for antigens delivery have aroused growing interest in the field of cancer immunotherapy. Their potency to stimulate innate immunity and to promote intracellular antigen delivery into antigen-presenting cells could be exploited to elicit a strong and specific cellular immune response against tumor cells. We previously described genetically-modified and attenuated Pseudomonas aeruginosa vectors able to deliver in vivo protein antigens into antigen-presenting cells, through Type 3 secretion system of the bacteria. Using this approach, we managed to protect immunized mice against aggressive B16 melanoma development in both a prophylactic and therapeutic setting. In this study, we further investigated the antigen-specific CD8+ T cell response, in terms of phenotypic and functional aspects, obtained after immunizations with a killed but metabolically active P. aeruginosa attenuated vector. We demonstrated that P. aeruginosa vaccine induces a highly functional pool of antigen-specific CD8+ T cell able to infiltrate the tumor. Furthermore, multiple immunizations allowed the development of a long-lasting immune response, represented by a pool of predominantly effector memory cells which protected mice against late tumor challenge. Overall, killed but metabolically active P. aeruginosa vector is a safe and promising approach for active and specific antitumor immunotherapy.

NK Cell-Mediated Regulation of Protective Memory Responses against Intracellular Ehrlichial Pathogens.

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Samar Habib

Full Text Available Ehrlichiae are gram-negative obligate intracellular bacteria that cause potentially fatal human monocytic ehrlichiosis. We previously showed that natural killer (NK cells play a critical role in host defense against Ehrlichia during primary infection. However, the contribution of NK cells to the memory response against Ehrlichia remains elusive. Primary infection of C57BL/6 mice with Ehrlichia muris provides long-term protection against a second challenge with the highly virulent Ixodes ovatus Ehrlichia (IOE, which ordinarily causes fatal disease in naïve mice. Here, we show that the depletion of NK cells in E. muris-primed mice abrogates the protective memory response against IOE. Approximately, 80% of NK cell-depleted E. muris-primed mice succumbed to lethal IOE infection on days 8-10 after IOE infection, similar to naïve mice infected with the same dose of IOE. The lack of a recall response in NK cell-depleted mice correlated with an increased bacterial burden, extensive liver injury, decreased frequency of Ehrlichia-specific IFN-γ-producing memory CD4+ and CD8+ T-cells, and a low titer of Ehrlichia-specific antibodies. Intraperitoneal infection of mice with E. muris resulted in the production of IL-15, IL-12, and IFN-γ as well as an expansion of activated NKG2D+ NK cells. The adoptive transfer of purified E. muris-primed hepatic and splenic NK cells into Rag2-/-Il2rg-/- recipient mice provided protective immunity against challenge with E. muris. Together, these data suggest that E. muris-induced memory-like NK cells, which contribute to the protective, recall response against Ehrlichia.

Varicella-Zoster Virus-Specific Cellular Immune Responses to the Live Attenuated Zoster Vaccine in Young and Older Adults.

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Weinberg, Adriana; Canniff, Jennifer; Rouphael, Nadine; Mehta, Aneesh; Mulligan, Mark; Whitaker, Jennifer A; Levin, Myron J

2017-07-15

The incidence and severity of herpes zoster (HZ) increases with age. The live attenuated zoster vaccine generates immune responses similar to HZ. We compared the immune responses to zoster vaccine in young and older to adults to increase our understanding of the immune characteristics that may contribute to the increased susceptibility to HZ in older adults. Young (25-40 y; n = 25) and older (60-80 y; n = 33) adults had similar magnitude memory responses to varicella-zoster virus (VZV) ex vivo restimulation measured by responder cell-frequency and flow cytometry, but the responses were delayed in older compared with young adults. Only young adults had an increase in dual-function VZV-specific CD4 + and CD8 + T cell effectors defined by coexpression of IFN-γ, IL-2, and CD107a after vaccination. In contrast, older adults showed marginal increases in VZV-specific CD8 + CD57 + senescent T cells after vaccination, which were already higher than those of young adults before vaccination. An increase in VZV-stimulated CD4 + CD69 + CD57 + PD1 + and CD8 + CD69 + CD57 + PD1 + T cells from baseline to postvaccination was associated with concurrent decreased VZV-memory and CD8 + effector responses, respectively, in older adults. Blocking the PD1 pathway during ex vivo VZV restimulation increased the CD4 + and CD8 + proliferation, but not the effector cytokine production, which modestly increased with TIM-3 blockade. We conclude that high proportions of senescent and exhausted VZV-specific T cells in the older adults contribute to their poor effector responses to a VZV challenge. This may underlie their inability to contain VZV reactivation and prevent the development of HZ. Copyright © 2017 by The American Association of Immunologists, Inc.

Vaccination Enhances Early Immune Responses in White Shrimp Litopenaeus vannamei after Secondary Exposure to Vibrio alginolyticus

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Lin, Yong-Chin; Chen, Jiann-Chu; Morni, Wan Zabidii W.; Putra, Dedi Fazriansyah; Huang, Chien-Lun; Li, Chang-Che; Hsieh, Jen-Fang

2013-01-01

Background Recent work suggested that the presence of specific memory or some form of adaptive immunity occurs in insects and shrimp. Hypervariable pattern recognition molecules, known as Down syndrome cell adhesion molecules, are able to mount specific recognition, and immune priming in invertebrates. In the present study, we attempted to understand the immune response pattern of white shrimp Litopenaeus vannamei which received primary (PE) and secondary exposure (SE) to Vibrio alginolyticus. Methodology Immune parameters and proliferation of haematopoietic tissues (HPTs) of shrimp which had received PE and SE to V. alginolyticus were measured. In the PE trial, the immune parameters and proliferation of HPTs of shrimp that received heat-killed V. alginolyticus (HVa) and formalin-inactivated V. alginolyticus (FVa) were measured. Mortality, immune parameters and proliferation of HPTs of 7-day-HVa-PE shrimp (shrimp that received primary exposure to HVa after 7 days) and 7-day-FVa-PE shrimp (shrimp that received primary exposure to FVa after 7 days) following SE to live V. alginolyticus (LVa) were measured. Phagocytic activity and clearance efficiency were examined for the 7∼35-day-HVa-PE and FVa-PE shrimp. Results HVa-receiving shrimp showed an earlier increase in the immune response on day 1, whereas FVa-receiving shrimp showed a late increase in the immune response on day 5. The 7-day-FVa-PE shrimp showed enhancement of immunity when encountering SE to LVa, whereas 7-day-HVa-PE shrimp showed a minor enhancement in immunity. 7-day-FVa-PE shrimp showed higher proliferation and an HPT mitotic index. Both phagocytic activity and clearance maintained higher for both HVa-PE and FVa-PE shrimp after 28 days. Conclusions HVa- and FVa-receiving shrimp showed the bacteria agglutinated prior to being phagocytised. FVa functions as a vaccine, whereas HVa functions as an inducer and can be used as an immune adjuvant. A combined mixture of FVa and HVa can serve as a �

Immunomodulator-based enhancement of anti smallpox immune responses.

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Osmarie Martínez

Full Text Available The current live vaccinia virus vaccine used in the prevention of smallpox is contraindicated for millions of immune-compromised individuals. Although vaccination with the current smallpox vaccine produces protective immunity, it might result in mild to serious health complications for some vaccinees. Thus, there is a critical need for the production of a safe virus-free vaccine against smallpox that is available to everyone. For that reason, we investigated the impact of imiquimod and resiquimod (Toll-like receptors agonists, and the codon-usage optimization of the vaccinia virus A27L gene in the enhancement of the immune response, with intent of producing a safe, virus-free DNA vaccine coding for the A27 vaccinia virus protein.We analyzed the cellular-immune response by measuring the IFN-γ production of splenocytes by ELISPOT, the humoral-immune responses measuring total IgG and IgG2a/IgG1 ratios by ELISA, and the TH1 and TH2 cytokine profiles by ELISA, in mice immunized with our vaccine formulation.The proposed vaccine formulation enhanced the A27L vaccine-mediated production of IFN-γ on mouse spleens, and increased the humoral immunity with a TH1-biased response. Also, our vaccine induced a TH1 cytokine milieu, which is important against viral infections.These results support the efforts to find a new mechanism to enhance an immune response against smallpox, through the implementation of a safe, virus-free DNA vaccination platform.

Immunomodulator-based enhancement of anti smallpox immune responses.

Science.gov (United States)

Martínez, Osmarie; Miranda, Eric; Ramírez, Maite; Santos, Saritza; Rivera, Carlos; Vázquez, Luis; Sánchez, Tomás; Tremblay, Raymond L; Ríos-Olivares, Eddy; Otero, Miguel

2015-01-01

The current live vaccinia virus vaccine used in the prevention of smallpox is contraindicated for millions of immune-compromised individuals. Although vaccination with the current smallpox vaccine produces protective immunity, it might result in mild to serious health complications for some vaccinees. Thus, there is a critical need for the production of a safe virus-free vaccine against smallpox that is available to everyone. For that reason, we investigated the impact of imiquimod and resiquimod (Toll-like receptors agonists), and the codon-usage optimization of the vaccinia virus A27L gene in the enhancement of the immune response, with intent of producing a safe, virus-free DNA vaccine coding for the A27 vaccinia virus protein. We analyzed the cellular-immune response by measuring the IFN-γ production of splenocytes by ELISPOT, the humoral-immune responses measuring total IgG and IgG2a/IgG1 ratios by ELISA, and the TH1 and TH2 cytokine profiles by ELISA, in mice immunized with our vaccine formulation. The proposed vaccine formulation enhanced the A27L vaccine-mediated production of IFN-γ on mouse spleens, and increased the humoral immunity with a TH1-biased response. Also, our vaccine induced a TH1 cytokine milieu, which is important against viral infections. These results support the efforts to find a new mechanism to enhance an immune response against smallpox, through the implementation of a safe, virus-free DNA vaccination platform.

Stress proteins and the immune response.

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Moseley, P

2000-07-25

The heat shock or stress response is one of the most highly conserved adaptive responses in nature. In single cell organisms, the stress response confers tolerance to a variety of stresses including hyperthermia, hyperoxia, hypoxia, and other perturbations, which alter protein synthesis. This tolerance phenomenon is also extremely important in the multicellular organism, resulting in not only thermal tolerance, but also resistance to stresses of the whole organism such as ischemia-reperfusion injury. Moreover, recent data indicates that these stress proteins have the ability to modulate the cellular immune response. Although the terms heat shock proteins (HSPs) and stress proteins are often used interchangeably, the term stress proteins includes the HSPs, the glucose-regulated proteins (GRPs) and ubiquitin. The stress proteins may be grouped by molecular weight ranging from the large 110 kDa HSP110 to ubiquitin at 8 kDa. These proteins serve as cellular chaperones, participating in protein synthesis and transport through the various cellular compartments. Because these proteins have unique cellular localizations, the chaperone function of the stress proteins often involves a transfer of peptides between stress proteins as the peptide is moved between cellular compartments. For example, HSP70 is a cytosolic and nuclear chaperone, which is critical for the transfer of cellular peptides in the mitochondrion through a hand-off that involves mitochondrial HSP60 at the inner mitochondrial membrane. Similarly, cytosolic proteins are transferred from HSP70 to gp96 as they move into the endoplasmic reticulum. The central role of the stress proteins in the transfer of peptides through the cell may be responsible for the recently recognized importance of the stress proteins in the modulation of the immune system [Feder, M.E., Hofmann, G.E., 1999. Heat-shock proteins, molecular chaperones, and the stress response: evolutionary and ecological physiology. Annu. Rev. Physiol. 61

Maternal immunity enhances Mycoplasma hyopneumoniae vaccination induced cell-mediated immune responses in piglets.

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Bandrick, Meggan; Theis, Kara; Molitor, Thomas W

2014-06-05

Passively acquired maternal derived immunity (MDI) is a double-edged sword. Maternal derived antibody-mediated immunity (AMI) and cell-mediated immunity (CMI) are critical immediate defenses for the neonate; however, MDI may interfere with the induction of active immunity in the neonate, i.e. passive interference. The effect of antigen-specific MDI on vaccine-induced AMI and CMI responses to Mycoplasma hyopneumoniae (M. hyopneumoniae) was assessed in neonatal piglets. To determine whether CMI and AMI responses could be induced in piglets with MDI, piglets with high and low levels of maternal M. hyopneumoniae-specific immunity were vaccinated against M. hyopneumoniae at 7 d of age. Piglet M. hyopneumoniae-specific antibody, lymphoproliferation, and delayed type hypersensitivity (DTH) responses were measured 7 d and 14 d post vaccination. Piglets with M. hyopneumoniae-specific MDI failed to show vaccine-induced AMI responses; there was no rise in M. hyopneumoniae antibody levels following vaccination of piglets in the presence of M. hyopneumoniae-specific MDI. However, piglets with M. hyopneumoniae-specific MDI had primary (antigen-specific lymphoproliferation) and secondary (DTH) M. hyopneumoniae-specific CMI responses following vaccination. In this study neonatal M. hyopneumoniae-specific CMI was not subject to passive interference by MDI. Further, it appears that both maternal derived and endogenous CMI contribute to M. hyopneumoniae-specific CMI responses in piglets vaccinated in the face of MDI.

Innate immune memory: implications for development of pediatric immunomodulatory agents and adjuvanted vaccines

NARCIS (Netherlands)

Levy, O.; Netea, M.G.

2014-01-01

Unique features of immunity early in life include a distinct immune system particularly reliant on innate immunity, with weak T helper (Th)1-polarizing immune responses, and impaired responses to certain vaccines leading to a heightened susceptibility to infection. To these important aspects, we now

Immune transfer studies in canine allogeneic marrow graft donor-recipient pairs

International Nuclear Information System (INIS)

Grosse-Wilde, H.; Krumbacher, K.; Schuening, F.D.; Doxiadis, I.; Mahmoud, H.K.; Emde, C.; Schmidt-Weinmar, A.; Schaefer, U.W.

1986-01-01

Transfer of immunity occurring with bone marrow grafting was studied using the dog as a preclinical model. Allogeneic bone marrow transplantation (BMT) was performed between DLA-identical beagle litter-mates. The donors were immunized with tetanus toxoid (TT) or sheep red blood cells (SRBC), and their humoral response was monitored by hemagglutination. The recipients of bone marrow from TT-immunized donors showed a marked increase of antibody titer one week posttransplantation, while in the recipients of marrow from SRBC immunized donors the antibody titers were considerably lower. Within the following 60 days the antibody titers in both groups diminished gradually to pregrafting levels. Control experiments in which cell-free plasma from donors immunized with TT and SRBC respectively was transfused indicated that the initial rise of specific antibody titers after marrow grafting is likely to be due to a passive transfer of humoral immunity. A single challenge of these marrow graft recipients with the respective antigen 15-18 weeks posttransplantation led to a secondary type of humoral immune response. It could be demonstrated that transfer of memory against TT or SRBC was independent from the actual antibody titer and the time of vaccination of the donor. One dog was immunized with TT after serving as marrow donor. When the donor had shown an antibody response, a peripheral blood leukocytes (PBL) transfusion was given to his chimera. Subsequent challenge of the latter resulted in a secondary type of specific antibody response. This indicates that specific cellular-bound immunological memory can be transferred after BMT from the donor to his allogeneic bone marrow chimera by transfusion of peripheral blood leukocytes. The data may be of importance in clinical BMT to protect patients during the phase of reduced immune reactivity by transfer of memory cells

Immunomodulator-Based Enhancement of Anti Smallpox Immune Responses

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Martínez, Osmarie; Miranda, Eric; Ramírez, Maite; Santos, Saritza; Rivera, Carlos; Vázquez, Luis; Sánchez, Tomás; Tremblay, Raymond L.; Ríos-Olivares, Eddy; Otero, Miguel

2015-01-01

Background The current live vaccinia virus vaccine used in the prevention of smallpox is contraindicated for millions of immune-compromised individuals. Although vaccination with the current smallpox vaccine produces protective immunity, it might result in mild to serious health complications for some vaccinees. Thus, there is a critical need for the production of a safe virus-free vaccine against smallpox that is available to everyone. For that reason, we investigated the impact of imiquimod and resiquimod (Toll-like receptors agonists), and the codon-usage optimization of the vaccinia virus A27L gene in the enhancement of the immune response, with intent of producing a safe, virus-free DNA vaccine coding for the A27 vaccinia virus protein. Methods We analyzed the cellular-immune response by measuring the IFN-γ production of splenocytes by ELISPOT, the humoral-immune responses measuring total IgG and IgG2a/IgG1 ratios by ELISA, and the TH1 and TH2 cytokine profiles by ELISA, in mice immunized with our vaccine formulation. Results The proposed vaccine formulation enhanced the A27L vaccine-mediated production of IFN-γ on mouse spleens, and increased the humoral immunity with a TH1-biased response. Also, our vaccine induced a TH1 cytokine milieu, which is important against viral infections. Conclusion These results support the efforts to find a new mechanism to enhance an immune response against smallpox, through the implementation of a safe, virus-free DNA vaccination platform. PMID:25875833

Major Histocompatibilty Complex-Restricted Adaptive Immune Responses to CT26 Colon Cancer Cell Line in Mixed Allogeneic Chimera.

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Lee, K W; Choi, B; Kim, Y M; Cho, C W; Park, H; Moon, J I; Choi, G-S; Park, J B; Kim, S J

2017-06-01

Although the induction of mixed allogeneic chimera shows promising clinical tolerance results in organ transplantation, its clinical relevance as an anti-cancer therapy is yet unknown. We introduced a mixed allogenic chimera setting with the use of a murine colon cancer cell line, CT26, by performing double bone marrow transplantation. We analyzed donor- and recipient-restricted anti-cancer T-cell responses, and phenotypes of subpopulations of T cells. The protocol involves challenging 1 × 10 5 cells of CT26 cells intra-hepatically on day 50 after bone marrow transplantation, and, by use of CT26 lysates and an H-2L d -restricted AH1 pentamer, flow cytometric analysis was performed to detect the generation of cancer-specific CD4 + and CD8 + T cells at various time points. We found that immunocompetence against tumors depends heavily on cancer-specific CD8 + T-cell responses in a major histocompatibility complex-restricted manner; the evidence was further supported by the increase of interferon-γ-secreting CD4 + T cells. Moreover, we demonstrated that during the effector immune response to CT26 cancer challenge, there was a presence of central memory cells (CD62L hi CCR7 + ) as well as effector memory cells (CD62L lo CCR7 - ). Moreover, mixed allogeneic chimeras (BALB/c to C56BL/6 or vice versa) showed similar or heightened immune responses to CT26 cells compared with that of wild-type mice. Our results suggest that the responses of primary immunocompetency and of pre-existing memory T cells against allogeneic cancer are sustained and preserved long-term in a mixed allogeneic chimeric environment. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of mucosal and systemic immune responses elicited by GPI-0100- adjuvanted influenza vaccine delivered by different immunization strategies.

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Heng Liu

Full Text Available Vaccines for protection against respiratory infections should optimally induce a mucosal immune response in the respiratory tract in addition to a systemic immune response. However, current parenteral immunization modalities generally fail to induce mucosal immunity, while mucosal vaccine delivery often results in poor systemic immunity. In order to find an immunization strategy which satisfies the need for induction of both mucosal and systemic immunity, we compared local and systemic immune responses elicited by two mucosal immunizations, given either by the intranasal (IN or the intrapulmonary (IPL route, with responses elicited by a mucosal prime followed by a systemic boost immunization. The study was conducted in BALB/c mice and the vaccine formulation was an influenza subunit vaccine supplemented with GPI-0100, a saponin-derived adjuvant. While optimal mucosal antibody titers were obtained after two intrapulmonary vaccinations, optimal systemic antibody responses were achieved by intranasal prime followed by intramuscular boost. The latter strategy also resulted in the best T cell response, yet, it was ineffective in inducing nose or lung IgA. Successful induction of secretory IgA, IgG and T cell responses was only achieved with prime-boost strategies involving intrapulmonary immunization and was optimal when both immunizations were given via the intrapulmonary route. Our results underline that immunization via the lungs is particularly effective for priming as well as boosting of local and systemic immune responses.

Evaluation of Mucosal and Systemic Immune Responses Elicited by GPI-0100- Adjuvanted Influenza Vaccine Delivered by Different Immunization Strategies

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Liu, Heng; Patil, Harshad P.; de Vries-Idema, Jacqueline; Wilschut, Jan; Huckriede, Anke

2013-01-01

Vaccines for protection against respiratory infections should optimally induce a mucosal immune response in the respiratory tract in addition to a systemic immune response. However, current parenteral immunization modalities generally fail to induce mucosal immunity, while mucosal vaccine delivery often results in poor systemic immunity. In order to find an immunization strategy which satisfies the need for induction of both mucosal and systemic immunity, we compared local and systemic immune responses elicited by two mucosal immunizations, given either by the intranasal (IN) or the intrapulmonary (IPL) route, with responses elicited by a mucosal prime followed by a systemic boost immunization. The study was conducted in BALB/c mice and the vaccine formulation was an influenza subunit vaccine supplemented with GPI-0100, a saponin-derived adjuvant. While optimal mucosal antibody titers were obtained after two intrapulmonary vaccinations, optimal systemic antibody responses were achieved by intranasal prime followed by intramuscular boost. The latter strategy also resulted in the best T cell response, yet, it was ineffective in inducing nose or lung IgA. Successful induction of secretory IgA, IgG and T cell responses was only achieved with prime-boost strategies involving intrapulmonary immunization and was optimal when both immunizations were given via the intrapulmonary route. Our results underline that immunization via the lungs is particularly effective for priming as well as boosting of local and systemic immune responses. PMID:23936066

Microneedle array design determines the induction of protective memory CD8+ T cell responses induced by a recombinant live malaria vaccine in mice.

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John B Carey

Full Text Available Vaccine delivery into the skin has received renewed interest due to ease of access to the immune system and microvasculature, however the stratum corneum (SC, must be breached for successful vaccination. This has been achieved by removing the SC by abrasion or scarification or by delivering the vaccine intradermally (ID with traditional needle-and-syringes or with long microneedle devices. Microneedle patch-based transdermal vaccine studies have predominantly focused on antibody induction by inactivated or subunit vaccines. Here, our principal aim is to determine if the design of a microneedle patch affects the CD8(+ T cell responses to a malaria antigen induced by a live vaccine.Recombinant modified vaccinia virus Ankara (MVA expressing a malaria antigen was percutaneously administered to mice using a range of silicon microneedle patches, termed ImmuPatch, that differed in microneedle height, density, patch area and total pore volume. We demonstrate that microneedle arrays that have small total pore volumes induce a significantly greater proportion of central memory T cells that vigorously expand to secondary immunization. Microneedle-mediated vaccine priming induced significantly greater T cell immunity post-boost and equivalent protection against malaria challenge compared to ID vaccination. Notably, unlike ID administration, ImmuPatch-mediated vaccination did not induce inflammatory responses at the site of immunization or in draining lymph nodes.This study demonstrates that the design of microneedle patches significantly influences the magnitude and memory of vaccine-induced CD8(+ T cell responses and can be optimised for the induction of desired immune responses. Furthermore, ImmuPatch-mediated delivery may be of benefit to reducing unwanted vaccine reactogenicity. In addition to the advantages of low cost and lack of pain, the development of optimised microneedle array designs for the induction of T cell responses by live vaccines aids

Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

International Nuclear Information System (INIS)

Hennings, Leah; Artaud, Cecile; Jousheghany, Fariba; Monzavi-Karbassi, Behjatolah; Pashov, Anastas; Kieber-Emmons, Thomas

2011-01-01

Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I), and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses

Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

Energy Technology Data Exchange (ETDEWEB)

Hennings, Leah; Artaud, Cecile; Jousheghany, Fariba; Monzavi-Karbassi, Behjatolah; Pashov, Anastas; Kieber-Emmons, Thomas, E-mail: tke@uams.edu [Winthrop P. Rockefeller Cancer Institute and Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR 72205 (United States)

2011-11-11

Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I), and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses.

Pleurodeles Waltl Humoral Immune Response under Spaceflight Conditions

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Bascove, Matthieu; Touche, Nadege; Frippiat, Jean-Pol

2008-06-01

The immune system is an important regulatory mechanism affected by spaceflights. In a previous work, we performed a first study of the humoral immune response induced by the immunization of Pleurodeles waltl during a 5 months stay onboard the Mir space station. This analysis indicated that heavy-chain variable domains of specific IgM are encoded by genes of the VHII and VHVI families. However, the contributions of these two families to IgM heavy-chains are different in flown animals [1]. To better understand this immune response modification, we have now determined how individual VH genes have been used to build specific IgM binding sites in animals immunized on earth or in space. This new study revealed quantitative and qualitative modifications in VH genes expression. These data confirm that a spaceflight might affect the humoral response.

Origins of adaptive immunity.

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Liongue, Clifford; John, Liza B; Ward, Alister

2011-01-01

Adaptive immunity, involving distinctive antibody- and cell-mediated responses to specific antigens based on "memory" of previous exposure, is a hallmark of higher vertebrates. It has been argued that adaptive immunity arose rapidly, as articulated in the "big bang theory" surrounding its origins, which stresses the importance of coincident whole-genome duplications. Through a close examination of the key molecules and molecular processes underpinning adaptive immunity, this review suggests a less-extreme model, in which adaptive immunity emerged as part of longer evolutionary journey. Clearly, whole-genome duplications provided additional raw genetic materials that were vital to the emergence of adaptive immunity, but a variety of other genetic events were also required to generate some of the key molecules, whereas others were preexisting and simply co-opted into adaptive immunity.

The development of a fully-integrated immune response model (FIRM) simulator of the immune response through integration of multiple subset models.

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Palsson, Sirus; Hickling, Timothy P; Bradshaw-Pierce, Erica L; Zager, Michael; Jooss, Karin; O'Brien, Peter J; Spilker, Mary E; Palsson, Bernhard O; Vicini, Paolo

2013-09-28

The complexity and multiscale nature of the mammalian immune response provides an excellent test bed for the potential of mathematical modeling and simulation to facilitate mechanistic understanding. Historically, mathematical models of the immune response focused on subsets of the immune system and/or specific aspects of the response. Mathematical models have been developed for the humoral side of the immune response, or for the cellular side, or for cytokine kinetics, but rarely have they been proposed to encompass the overall system complexity. We propose here a framework for integration of subset models, based on a system biology approach. A dynamic simulator, the Fully-integrated Immune Response Model (FIRM), was built in a stepwise fashion by integrating published subset models and adding novel features. The approach used to build the model includes the formulation of the network of interacting species and the subsequent introduction of rate laws to describe each biological process. The resulting model represents a multi-organ structure, comprised of the target organ where the immune response takes place, circulating blood, lymphoid T, and lymphoid B tissue. The cell types accounted for include macrophages, a few T-cell lineages (cytotoxic, regulatory, helper 1, and helper 2), and B-cell activation to plasma cells. Four different cytokines were accounted for: IFN-γ, IL-4, IL-10 and IL-12. In addition, generic inflammatory signals are used to represent the kinetics of IL-1, IL-2, and TGF-β. Cell recruitment, differentiation, replication, apoptosis and migration are described as appropriate for the different cell types. The model is a hybrid structure containing information from several mammalian species. The structure of the network was built to be physiologically and biochemically consistent. Rate laws for all the cellular fate processes, growth factor production rates and half-lives, together with antibody production rates and half-lives, are provided. The

Modulation of the innate immune responses in the striped ...

African Journals Online (AJOL)

Thus, most of the innate non-specific immune responses are inducible though they are constitutive of fish immune system exhibiting a basal level of activity even in the absence of pathogen challenge. Keywords: Aeromonas hydrophila, Experimental challenge, Innate immune response, Striped snakehead murrel ...

Selective Memory to Apoptotic Cell-Derived Self-Antigens with Implications for Systemic Lupus Erythematosus Development.

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Duhlin, Amanda; Chen, Yunying; Wermeling, Fredrik; Sedimbi, Saikiran K; Lindh, Emma; Shinde, Rahul; Halaby, Marie Jo; Kaiser, Ylva; Winqvist, Ola; McGaha, Tracy L; Karlsson, Mikael C I

2016-10-01

Autoimmune diseases are characterized by pathogenic immune responses to self-antigens. In systemic lupus erythematosus (SLE), many self-antigens are found in apoptotic cells (ACs), and defects in removal of ACs from the body are linked to a risk for developing SLE. This includes pathological memory that gives rise to disease flares. In this study, we investigated how memory to AC-derived self-antigens develops and the contribution of self-memory to the development of lupus-related pathology. Multiple injections of ACs without adjuvant into wild-type mice induce a transient primary autoimmune response without apparent anti-nuclear Ab reactivity or kidney pathology. Interestingly, as the transient Ab response reached baseline, a single boost injection fully recalled the immune response to ACs, and this memory response was furthermore transferable into naive mice. Additionally, the memory response contains elements of pathogenicity, accompanied by selective memory to selective Ags. Thus, we provide evidence for a selective self-memory that underlies progression of the response to self-antigens with implications for SLE development therapy. Copyright © 2016 by The American Association of Immunologists, Inc.

Adenovirus Vector-Derived VA-RNA-Mediated Innate Immune Responses

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Hiroyuki Mizuguchi

2011-07-01

Full Text Available The major limitation of the clinical use of replication-incompetent adenovirus (Ad vectors is the interference by innate immune responses, including induction of inflammatory cytokines and interferons (IFN, following in vivo application of Ad vectors. Ad vector-induced production of inflammatory cytokines and IFNs also results in severe organ damage and efficient induction of acquired immune responses against Ad proteins and transgene products. Ad vector-induced innate immune responses are triggered by the recognition of Ad components by pattern recognition receptors (PRRs. In order to reduce the side effects by Ad vector-induced innate immune responses and to develop safer Ad vectors, it is crucial to clarify which PRRs and which Ad components are involved in Ad vector-induced innate immune responses. Our group previously demonstrated that myeloid differentiating factor 88 (MyD88 and toll-like receptor 9 (TLR9 play crucial roles in the Ad vector-induced inflammatory cytokine production in mouse bone marrow-derived dendritic cells. Furthermore, our group recently found that virus associated-RNAs (VA-RNAs, which are about 160 nucleotide-long non-coding small RNAs encoded in the Ad genome, are involved in IFN production through the IFN-β promoter stimulator-1 (IPS-1-mediated signaling pathway following Ad vector transduction. The aim of this review is to highlight the Ad vector-induced innate immune responses following transduction, especially VA-RNA-mediated innate immune responses. Our findings on the mechanism of Ad vector-induced innate immune responses should make an important contribution to the development of safer Ad vectors, such as an Ad vector lacking expression of VA-RNAs.

Immune response induction in the central nervous system

DEFF Research Database (Denmark)

Owens, Trevor; Babcock, Alicia

2002-01-01

The primary function of the immune response is protection of the host against infection with pathogens, including viruses. Since viruses can infect any tissue of the body, including the central nervous system (CNS), it is logical that cells of the immune system should equally have access to all...... tissues. Nevertheless, the brain and spinal cord are noted for their lack of immune presence. Relative to other organ systems, the CNS appears immunologically privileged. Furthermore, when immune responses do occur in the CNS, they are frequently associated with deleterious effects such as inflammatory...

Senescence in immune priming and attractiveness in a beetle.

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Daukšte, J; Kivleniece, I; Krama, T; Rantala, M J; Krams, I

2012-07-01

Age-related decline in immune activity is referred to as immunosenescence and has been observed for both the adaptive immune response of vertebrates and the innate immune system of invertebrates. Because maintaining a basic level of immune defence and mounting an immune response is costly, optimal investment in immune function should vary over a wide range of individual states such as the individual's age. In this study, we tested whether the immune response and immunological priming within individuals become less efficient with age using mealworm beetles, Tenebrio molitor, as a model organism. We also tested whether ageing and immunological priming affected the odours produced by males. We found that young males of T. molitor were capable of mounting an immune response a sterile nylon monofilament implant with the potential to exhibit a simple form of immune memory through mechanisms of immune priming. Older males did not increase their immune response to a second immune challenge, which negatively affected their sexual attractiveness and remaining life span. Our results indicate that the immune system of older males in T. molitor is less effective, suggesting complex evolutionary trade-offs between ageing, immune response and sexual attractiveness. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Tumor vaccine composed of C-class CpG oligodeoxynucleotides and irradiated tumor cells induces long-term antitumor immunity

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Cerkovnik Petra

2010-09-01

Full Text Available Abstract Background An ideal tumor vaccine should activate both effector and memory immune response against tumor-specific antigens. Beside the CD8+ T cells that play a central role in the generation of a protective immune response and of long-term memory, dendritic cells (DCs are important for the induction, coordination and regulation of the adaptive immune response. The DCs can conduct all of the elements of the immune orchestra and are therefore a fundamental target and tool for vaccination. The present study was aimed at assessing the ability of tumor vaccine composed of C-class CpG ODNs and irradiated melanoma tumor cells B16F1 followed by two additional injections of CpG ODNs to induce the generation of a functional long-term memory response in experimental tumor model in mice (i.p. B16F1. Results It has been shown that the functional memory response in vaccinated mice persists for at least 60 days after the last vaccination. Repeated vaccination also improves the survival of experimental animals compared to single vaccination, whereas the proportion of animals totally protected from the development of aggressive i.p. B16F1 tumors after vaccination repeated three times varies between 88.9%-100.0%. Additionally, the long-term immune memory and tumor protection is maintained over a prolonged period of time of at least 8 months. Finally, it has been demonstrated that following the vaccination the tumor-specific memory cells predominantly reside in bone marrow and peritoneal tissue and are in a more active state than their splenic counterparts. Conclusions In this study we demonstrated that tumor vaccine composed of C-class CpG ODNs and irradiated tumor cells followed by two additional injections of CpG ODNs induces a long-term immunity against aggressive B16F1 tumors.

Interplay between behavioural thermoregulation and immune response in mealworms.

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Catalán, Tamara P; Niemeyer, Hermann M; Kalergis, Alexis M; Bozinovic, Francisco

2012-11-01

Since the preferential body temperature should positively correlate with physiological performance, behavioural fever should enhance an organism's immune response under an immune challenge. Here we have studied the preferential body temperature (T(p)) and its consequences on immune response performance after an immune challenge in larvae of Tenebrio molitor. We evaluated T(p) and immune responses of larvae following a challenge with various concentrations of lipopolysaccharide (LPS), and we studied the correlation between T(p) and two immune traits, namely antibacterial and phenoloxidase (PO) activities. Larvae that were immune challenged with higher LPS concentrations (C(50) and C(100)) preferred in average, warmer temperatures than did larvae challenged with lower concentrations (C(0) and C(25)). T(p) of C(25)-C(100) (challenged)-mealworms was 2.3°C higher than of C(0) (control) larvae. At lower LPS concentration immune challenge (C(0) and C(25)) antibacterial activity correlated positively with T(p), but at C(50) and C(100) correlation was lose. PO activity was higher at higher LPS concentration, but its magnitude of response did not correlate with T(p) Our data suggest that behavioural fever may have a positive effect on host performance by enhancing antibacterial response under a low pathogen load situation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Immunization with Brucella VirB proteins reduces organ colonization in mice through a Th1-type immune response and elicits a similar immune response in dogs.

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Pollak, Cora N; Wanke, María Magdalena; Estein, Silvia M; Delpino, M Victoria; Monachesi, Norma E; Comercio, Elida A; Fossati, Carlos A; Baldi, Pablo C

2015-03-01

VirB proteins from Brucella spp. constitute the type IV secretion system, a key virulence factor mediating the intracellular survival of these bacteria. Here, we assessed whether a Th1-type immune response against VirB proteins may protect mice from Brucella infection and whether this response can be induced in the dog, a natural host for Brucella. Splenocytes from mice immunized with VirB7 or VirB9 responded to their respective antigens with significant and specific production of gamma interferon (IFN-γ), whereas interleukin-4 (IL-4) was not detected. Thirty days after an intraperitoneal challenge with live Brucella abortus, the spleen load of bacteria was almost 1 log lower in mice immunized with VirB proteins than in unvaccinated animals. As colonization reduction seemed to correlate with a Th1-type immune response against VirB proteins, we decided to assess whether such a response could be elicited in the dog. Peripheral blood mononuclear cells (PBMCs) from dogs immunized with VirB proteins (three subcutaneous doses in QuilA adjuvant) produced significantly higher levels of IFN-γ than cells from control animals upon in vitro stimulation with VirB proteins. A skin test to assess specific delayed-type hypersensitivity was positive in 4 out of 5 dogs immunized with either VirB7 or VirB9. As both proteins are predicted to locate in the outer membrane of Brucella organisms, the ability of anti-VirB antibodies to mediate complement-dependent bacteriolysis of B. canis was assessed in vitro. Sera from dogs immunized with either VirB7 or VirB9, but not from those receiving phosphate-buffered saline (PBS), produced significant bacteriolysis. These results suggest that VirB-specific responses that reduce organ colonization by Brucella in mice can be also elicited in dogs. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

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

Maternal immune activation during pregnancy in rats impairs working memory capacity of the offspring.

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Murray, Brendan G; Davies, Don A; Molder, Joel J; Howland, John G

2017-05-01

Maternal immune activation during pregnancy is an environmental risk factor for psychiatric illnesses such as schizophrenia in the offspring. Patients with schizophrenia display an array of cognitive symptoms, including impaired working memory capacity. Rodent models have been developed to understand the relationship between maternal immune activation and the cognitive symptoms of schizophrenia. The present experiment was designed to test whether maternal immune activation with the viral mimetic polyinosinic:polycytidylic acid (polyI:C) during pregnancy affects working memory capacity of the offspring. Pregnant Long Evans rats were treated with either saline or polyI:C (4mg/kg; i.v.) on gestational day 15. Male offspring of the litters (2-3months of age) were subsequently trained on a nonmatching-to-sample task with odors. After a criterion was met, the rats were tested on the odor span task, which requires rats to remember an increasing span of different odors to receive food reward. Rats were tested using delays of approximately 40s during the acquisition of the task. Importantly, polyI:C- and saline-treated offspring did not differ in performance of the nonmatching-to-sample task suggesting that both groups could perform a relatively simple working memory task. In contrast, polyI:C-treated offspring had reduced span capacity in the middle and late phases of odor span task acquisition. After task acquisition, the rats were tested using the 40s delay and a 10min delay. Both groups showed a delay-dependent decrease in span, although the polyI:C-treated offspring had significantly lower spans regardless of delay. Our results support the validity of the maternal immune activation model for studying the cognitive symptoms of neurodevelopmental disorders such as schizophrenia. Copyright © 2017 Elsevier Inc. All rights reserved.

Immune response and anamnestic immune response in children after a 3-dose primary hepatitis b vaccination

International Nuclear Information System (INIS)

Afzal, M.F.; Sultan, M.A.; Saleemi, A.I.

2017-01-01

Diseases caused by Hepatitis B virus (HBV) have a worldwide distribution. Pakistan adopted the recommendations of World Health Organization (WHO) for routine universal infant vaccination against hepatitis B in 2002, currently being administered at 6, 10, and 14 weeks of age in a combination vaccine. This study was conducted to determine the immune response and anamnestic immune response in children, 9 months-10 years of age, after a 3-dose primary Hepatitis B vaccination. Methods: This cross sectional study was conducted in the Department of Paediatrics, King Edward Medical University/Mayo Hospital, Lahore, Pakistan, from January to June, 2014. A total of 200 children of either sex between the ages of 9 months to 10 years, docu mented to have received 3 doses of hepatitis B vaccines according to Expanded Program of Immunization (6,10,14 weeks) schedule in infancy, were recruited by consecutive sampling. The level of serum anti-HBsAb by ELIZA was measured. Children with anti-HBs titers =10 mIU/mL were considered to be immune. Those with anti-HBsAb levels <10 mIU/mL were offered a booster dose of infant recombinant hepatitis B vaccine. The second serum sample was obtained 21-28 days following the administration of the booster dose and the anamnestic immune response was measured. Data was analysed using SPSS 17 to determine the relation between time interval since last vaccination and antibody titer. Chi square test was applied. Results: Of the 200 children, protective antibody response was found in 58 percent. Median serological response was 18.60 (range 2.82-65.15). Antibody levels were found to have a statistically significant (p-value 0.019) negative correlation with the time since last administration of vaccine. A booster dose of Hepatitis B vaccine was administered to all non-responders, with each registering a statistically significant (p-value 0.00) anamnestic response. Conclusion: The vaccination schedule with short dosage interval was unable to provide

Persistence of memory B-cell and T-cell responses to the quadrivalent HPV vaccine in HIV-infected children.

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Weinberg, Adriana; Huang, Sharon; Moscicki, Anna-Barbara; Saah, Afred; Levin, Myron J

2018-04-24

To determine the magnitude and persistence of quadrivalent human papillomavirus (HPV)16 and HPV18 B-cell and T-cell memory after three or four doses of quadrivalent HPV vaccine (QHPV) in HIV-infected children. Seventy-four HIV-infected children immunized with four doses and 23 with three doses of QHPV had HPV16 and HPV18 IgG B-cell and IFNγ and IL2 T-cell ELISPOT performed at 2, 3.5 and 4-5 years after the last dose. HPV16 and HPV18 T-cell responses were similar in both treatment groups, with higher responses to HPV16 vs. HPV18. These HPV T-cell responses correlated with HIV disease characteristics at the study visits. Global T-cell function declined over time as measured by nonspecific mitogenic stimulation. B-cell memory was similar across treatment groups and HPV genotypes. There was a decline in HPV-specific B-cell memory over time that reached statistical significance for HPV16 in the four-dose group. B-cell and T-cell memory did not significantly differ after either three or four doses of QHPV in HIV-infected children. The clinical consequences of decreasing global T-cell function and HPV B-cell memory over time in HIV-infected children requires further investigation.

Dissociating response systems: erasing fear from memory.

Science.gov (United States)

Soeter, Marieke; Kindt, Merel

2010-07-01

In addition to the extensive evidence in animals, we previously showed that disrupting reconsolidation by noradrenergic blockade produced amnesia for the original fear response in humans. Interestingly, the declarative memory for the fear association remained intact. These results asked for a solid replication. Moreover, given the constructive nature of memories, the intact recollection of the fear association could eventually 'rebuild' the fear memory, resulting in the spontaneous recovery of the fear response. Yet, perseverance of the amnesic effects would have substantial clinical implications, as even the most effective treatments for psychiatric disorders display high percentages of relapse. Using a differential fear conditioning procedure in humans, we replicated our previous findings by showing that administering propranolol (40mg) prior to memory reactivation eliminated the startle fear response 24h later. But most importantly, this effect persisted at one month follow-up. Notably, the propranolol manipulation not only left the declarative memory for the acquired contingency untouched, but also skin conductance discrimination. In addition, a close association between declarative knowledge and skin conductance responses was found. These findings are in line with the supposed double dissociation of fear conditioning and declarative knowledge relative to the amygdala and hippocampus in humans. They support the view that skin conductance conditioning primarily reflects contingency learning, whereas the startle response is a rather specific measure of fear. Furthermore, the results indicate the absence of a causal link between the actual knowledge of a fear association and its fear response, even though they often operate in parallel. Interventions targeting the amygdalar fear memory may be essential in specifically and persistently dampening the emotional impact of fear. From a clinical and ethical perspective, disrupting reconsolidation points to promising

Transcriptional 'memory' of a stress: transient chromatin and memory (epigenetic) marks at stress-response genes.

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Avramova, Zoya

2015-07-01

Drought, salinity, extreme temperature variations, pathogen and herbivory attacks are recurring environmental stresses experienced by plants throughout their life. To survive repeated stresses, plants provide responses that may be different from their response during the first encounter with the stress. A different response to a similar stress represents the concept of 'stress memory'. A coordinated reaction at the organismal, cellular and gene/genome levels is thought to increase survival chances by improving the plant's tolerance/avoidance abilities. Ultimately, stress memory may provide a mechanism for acclimation and adaptation. At the molecular level, the concept of stress memory indicates that the mechanisms responsible for memory-type transcription during repeated stresses are not based on repetitive activation of the same response pathways activated by the first stress. Some recent advances in the search for transcription 'memory factors' are discussed with an emphasis on super-induced dehydration stress memory response genes in Arabidopsis. © 2015 The Author The Plant Journal © 2015 John Wiley & Sons Ltd.

The cellular memory disc of reprogrammed cells.

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Anjamrooz, Seyed Hadi

2013-04-01

The crucial facts underlying the low efficiency of cellular reprogramming are poorly understood. Cellular reprogramming occurs in nuclear transfer, induced pluripotent stem cell (iPSC) formation, cell fusion, and lineage-switching experiments. Despite these advances, there are three fundamental problems to be addressed: (1) the majority of cells cannot be reprogrammed, (2) the efficiency of reprogramming cells is usually low, and (3) the reprogrammed cells developed from a patient's own cells activate immune responses. These shortcomings present major obstacles for using reprogramming approaches in customised cell therapy. In this Perspective, the author synthesises past and present observations in the field of cellular reprogramming to propose a theoretical picture of the cellular memory disc. The current hypothesis is that all cells undergo an endogenous and exogenous holographic memorisation such that parts of the cellular memory dramatically decrease the efficiency of reprogramming cells, act like a barrier against reprogramming in the majority of cells, and activate immune responses. Accordingly, the focus of this review is mainly to describe the cellular memory disc (CMD). Based on the present theory, cellular memory includes three parts: a reprogramming-resistance memory (RRM), a switch-promoting memory (SPM) and a culture-induced memory (CIM). The cellular memory arises genetically, epigenetically and non-genetically and affects cellular behaviours. [corrected].

Dynamic Nature of Noncoding RNA Regulation of Adaptive Immune Response

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Franca Citarella

2013-08-01

Full Text Available Immune response plays a fundamental role in protecting the organism from infections; however, dysregulation often occurs and can be detrimental for the organism, leading to a variety of immune-mediated diseases. Recently our understanding of the molecular and cellular networks regulating the immune response, and, in particular, adaptive immunity, has improved dramatically. For many years, much of the focus has been on the study of protein regulators; nevertheless, recent evidence points to a fundamental role for specific classes of noncoding RNAs (ncRNAs in regulating development, activation and homeostasis of the immune system. Although microRNAs (miRNAs are the most comprehensive and well-studied, a number of reports suggest the exciting possibility that long ncRNAs (lncRNAs could mediate host response and immune function. Finally, evidence is also accumulating that suggests a role for miRNAs and other small ncRNAs in autocrine, paracrine and exocrine signaling events, thus highlighting an elaborate network of regulatory interactions mediated by different classes of ncRNAs during immune response. This review will explore the multifaceted roles of ncRNAs in the adaptive immune response. In particular, we will focus on the well-established role of miRNAs and on the emerging role of lncRNAs and circulating ncRNAs, which all make indispensable contributions to the understanding of the multilayered modulation of the adaptive immune response.

Innate immune response development in nestling tree swallows

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Stambaugh, T.; Houdek, B.J.; Lombardo, M.P.; Thorpe, P.A.; Caldwell, Hahn D.

2011-01-01

We tracked the development of innate immunity in nestling Tree Swallows (Tachycineta bicolor) and compared it to that of adults using blood drawn from nestlings during days 6, 12, and 18 of the ???20-day nestling period and from adults. Innate immunity was characterized using an in vitro assay of the ability of whole blood to kill Escherichia coli. The ability of whole blood to kill E. coli increased as nestlings matured. Neither this component of innate immunity nor right wing chord length on day18 were as developed as in adults indicating that development of the innate immune system and growth both continued after fledging. Narrow sense heritability analyses suggest that females with strong immune responses produced nestlings with strong immune responses. These data suggest nestling Tree Swallows allocated sufficient energy to support rapid growth to enable fledging by day 18, but that further development of innate immunity occurred post-fledging. ?? 2011 by the Wilson Ornithological Society.

Memory of Natural Killer Cells: A New Chance against Mycobacterium tuberculosis?

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José Alberto Choreño Parra

2017-08-01

Full Text Available Natural killer (NK cells are lymphocytes of the innate immune system, which play an important role in the initial defense against a wide variety of pathogens, including viruses and intracellular bacteria. NK cells produce cytokines that enhance immune responses directed toward pathogens and also exert cytotoxic activity against infected cells, thereby eliminating the reservoir of infection. Their role in defense against Mycobacterium tuberculosis (Mtb has been recently studied, and there is increasing evidence that highlight the importance of NK cell function during pulmonary tuberculosis (PTB, especially in the absence of optimal T-cell responses. Additionally, in the last years, it has been observed that NK cells mediate secondary responses against antigens to which they were previously exposed, an ability classically attributed to lymphocytes of the adaptive branch of immunity. This phenomenon, called “innate memory,” could have important implications in the efforts to develop therapies and vaccines to improve the initial phases of immune reactions against different microorganisms, especially those to which there is not yet available vaccines to prevent infection, as is the case for tuberculosis. Therefore, the possibility of inducing memory-like NK cells ready to act prior to contact with Mtb or during the earliest stages of infection becomes quite interesting. However, our understanding of the mechanisms of innate memory remains incomplete. Here, we review recent literature about the mechanisms involved in the formation and maintenance of NK cell memory and the role of these cells in the immune response during tuberculosis. Finally, we discuss if the current evidence is sufficient to substantiate that NK cells exert more rapid and robust secondary responses after consecutive encounters with Mtb.

Long-chain inulin for stimulating an immune response

NARCIS (Netherlands)

de Vos, Paulus; Vogt, Leonie

2017-01-01

The invention relates to a long chain inulin for influencing the immune response against a pathogen. The invention also relates to a combination comprising a long chain inulin and a vaccine for influencing the immune response against a pathogen, wherein the long chain inulin is orally administrated.

Reduced immune responses to purified protein derivative and Candida albicans in oral lichen planus.

Science.gov (United States)

Simark-Mattsson, Charlotte; Eklund, Christina

2013-10-01

Impairment of cellular immunity is reported in lichen planus, an autoimmune disease affecting mucosae and skin. Our aim was to investigate immune responses directed against a set of microbial antigens in patients with oral lichen planus and in matched controls. Venous blood was obtained, and the mononuclear cells were enriched by density gradient centrifugation. The proliferation of peripheral blood mononuclear cells was assessed, following stimulation with purified protein derivative (PPD), Candida albicans, phytohemagglutinin or when cells were left unstimulated, after three or six days of cell culture. The production of interleukin-1ß (IL-1ß), IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, IL-17, interferon-γ (IFN-γ), tumour necrosis factor-α (TNF-α), G-CSF, GM-CSF, MCP-1, MIP-ß was assessed in supernatants using the Bio-plex(®) assay and was complemented with ELISA for selected cytokines. Patients with oral lichen planus demonstrated reduced proliferative responses against PPD (P stimulated supernatants from patients with oral lichen planus. Collectively, the findings suggested that memory lymphocytes from patients with oral lichen planus (OLP) may have an impaired functional ability to react against certain recall antigens, as part of a generalized response, which may reflect immune regulatory processes. Further studies are needed to clarify the mechanisms of down-regulation in OLP pathogenesis and progression. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Engagement of NKG2D on bystander memory CD8 T cells promotes increased immunopathology following Leishmania major infection.

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Erika J Crosby

2014-02-01

Full Text Available One of the hallmarks of adaptive immunity is the development of a long-term pathogen specific memory response. While persistent memory T cells certainly impact the immune response during a secondary challenge, their role in unrelated infections is less clear. To address this issue, we utilized lymphocytic choriomeningitis virus (LCMV and Listeria monocytogenes immune mice to investigate whether bystander memory T cells influence Leishmania major infection. Despite similar parasite burdens, LCMV and Listeria immune mice exhibited a significant increase in leishmanial lesion size compared to mice infected with L. major alone. This increased lesion size was due to a severe inflammatory response, consisting not only of monocytes and neutrophils, but also significantly more CD8 T cells. Many of the CD8 T cells were LCMV specific and expressed gzmB and NKG2D, but unexpectedly expressed very little IFN-γ. Moreover, if CD8 T cells were depleted in LCMV immune mice prior to challenge with L. major, the increase in lesion size was lost. Strikingly, treating with NKG2D blocking antibodies abrogated the increased immunopathology observed in LCMV immune mice, showing that NKG2D engagement on LCMV specific memory CD8 T cells was required for the observed phenotype. These results indicate that bystander memory CD8 T cells can participate in an unrelated immune response and induce immunopathology through an NKG2D dependent mechanism without providing increased protection.

Immune Responses Involved in Mycobacterium Tuberculosis Infection

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Roghayeh Teimourpour

2016-09-01

Full Text Available Background and Objectives: Mycobacterium tuberculosis is the causative agent of tuberculosis (TB. Approximately one-third of the world's population is infected with M. tuberculosis. Despite the availability of drug and vaccine, it remains one of the leading causes of death in humans especially in developing countries. Epidemiological studies have indicated that only 10-30% of people exposed to tubercle bacillus are infected with M. tuberculosis, and at least 90% of the infected people finally do not acquire TB. The studies have indicated that the host efficient immune system has essential roles in the control of TB infection such that the highest rate of mortality and morbidity is seen in immunocompromised patients such as people infected with HIV. M. tuberculosis is an obligatory intracellular bacterium. It enters the body mainly through the respiratory tract and alveolar macrophages combat this pathogen most commonly. In addition to alveolar macrophages, various T-cell subpopulations need to be activated to overcome this bacterium's resistance to the host defense systems. CD4+ T cells, through production of several cytokines such as IFN-γ and TNF-α, and CD8+ T cells, through cytotoxic activities and induction of apoptosis in infected cells, play critical roles in inducing appropriate immune responses against M. tuberculosis. Although cell-mediated immunity is the cornerstone of host responses against TB and the recent studies have provided evidence for the importance of humoral and innate immune system in the control of TB, a profound understanding of the immune responses would provide a basis for development of new generations of vaccines and drugs. The present study addresses immune responses involved in M. tuberculosis infection.

Agouron and immune response to commercialize remune immune-based treatment.

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James, J S

1998-06-19

Agouron Pharmaceuticals agreed in June to collaborate with The Immune Response Corporation on the final development and marketing of an immune-based treatment for HIV. Remune, the vaccine developed by Dr. Jonas Salk, is currently in Phase III randomized trials with 2,500 patients, and the trials are expected to be completed in April 1999. Immune-based treatments have been difficult to test, as there is no surrogate marker, like viral load, to determine if the drug is working. Agouron agreed to participate in the joint venture after reviewing encouraging results from preliminary trials in which remune was taken in combination with highly active antiretroviral drugs.

Antibody and immune memory persistence post infant hepatitis B vaccination

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Hudu SA

2013-09-01

Full Text Available Shuaibu A Hudu,1,2 Yasmin A Malik,3 Mohd Taib Niazlin,1 Nabil S Harmal,1,4 Ariza Adnan,5 Ahmed S Alshrari,1 Zamberi Sekawi1 1Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Selangor, Malaysia; 2Department of Pathology and Medical Microbiology, College of Health Sciences, Usmanu Danfodiyo University Sokoto, Sokoto State, Nigeria; 3Department of Clinical Science, Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman, Selangor, Malaysia; 4Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen; 5Cluster of Laboratory Medical Sciences, Faculty of Medicine Universiti Teknologi MARA, Sungai Buloh, Selangor, Malaysia Objectives: This study aimed to evaluate the level of hepatitis B immunity among undergraduate students 23 years after commencement of the nationwide hepatitis B childhood immunization program in Malaysia. Methods: A total of 402 serum samples obtained from volunteer undergraduate students were screened for the presence of hepatitis B surface antibodies using qualitative ELISA. Results: Results showed that 62.7% of volunteers had protective anti-hepatitis B surface antigens (≥10 IU/L, of whom 67.9% received three doses of the vaccine. The estimated post-vaccination immunity was found to be at least 20 years, indicating persistent immunity against hepatitis B and a significant association (P < 0.05 with duration of vaccination. Anamnestic response 1 month post-hepatitis B booster was 94.0% and highly significant (P < 0.01. Isolated anti-hepatitis B core antigen (anti-HBc prevalence was found to be 5.0%, all having had a positive anamnestic response. Conclusion: Immunity after primary vaccination with hepatitis B recombinant vaccine persists for at least 20 years post-vaccination, with significant association with the number of vaccinations. Furthermore, the presence of anamnestic response to

Modulation of immune responses in stress by Yoga

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Arora Sarika

2008-01-01

Full Text Available Stress is a constant factor in today′s fastpaced life that can jeopardize our health if left unchecked. It is only in the last half century that the role of stress in every ailment from the common cold to AIDS has been emphasized, and the mechanisms involved in this process have been studied. Stress influences the immune response presumably through the activation of the hypothalamic-pituitary adrenal axis, hypothalamic pituitary-gonadal axis, and the sympathetic-adrenal-medullary system. Various neurotransmitters, neuropeptides, hormones, and cytokines mediate these complex bidirectional interactions between the central nervous system (CNS and the immune system. The effects of stress on the immune responses result in alterations in the number of immune cells and cytokine dysregulation. Various stress management strategies such as meditation, yoga, hypnosis, and muscle relaxation have been shown to reduce the psychological and physiological effects of stress in cancers and HIV infection. This review aims to discuss the effect of stress on the immune system and examine how relaxation techniques such as Yoga and meditation could regulate the cytokine levels and hence, the immune responses during stress.

Rapid host immune response and viral dynamics in herpes simplex virus-2 infection

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Schiffer, Joshua T; Corey, Lawrence

2014-01-01

Herpes Simplex Virus-2 (HSV-2) is episodically shed throughout the human genital tract. While high viral load correlates with development of genital ulcers, shedding also commonly occurs even when ulcers are not present, allowing for silent transmission during coitus and contributing to high seroprevalence of HSV-2 worldwide. Frequent viral reactivation occurs despite diverse and complementary host and viral mechanisms within ganglionic tissue that predispose towards latency, suggesting that viral replication may be constantly occurring in a small minority of neurons within the ganglia. Within genital mucosa, the in vivo expansion and clearance rates of HSV-2 are extremely rapid. Resident dendritic cells and memory HSV-specific T cells persist at prior sites of genital tract reactivation, and in conjunction with prompt innate recognition of infected cells, lead to rapid containment of infected cells. Shedding episodes vary greatly in duration and severity within a single person over time: this heterogeneity appears best explained by variation in the densities of host immunity across the genital tract. The fact that immune responses usually control viral replication in genital skin prior to development of lesions provides optimism that enhancing such responses could lead to effective vaccines and immunotherapies. PMID:23467247

Infectious Agents as Stimuli of Trained Innate Immunity

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Paulina Rusek

2018-02-01

Full Text Available The discoveries made over the past few years have modified the current immunological paradigm. It turns out that innate immunity cells can mount some kind of immunological memory, similar to that observed in the acquired immunity and corresponding to the defense mechanisms of lower organisms, which increases their resistance to reinfection. This phenomenon is termed trained innate immunity. It is based on epigenetic changes in innate immune cells (monocytes/macrophages, NK cells after their stimulation with various infectious or non-infectious agents. Many infectious stimuli, including bacterial or fungal cells and their components (LPS, β-glucan, chitin as well as viruses or even parasites are considered potent inducers of innate immune memory. Epigenetic cell reprogramming occurring at the heart of the phenomenon may provide a useful basis for designing novel prophylactic and therapeutic strategies to prevent and protect against multiple diseases. In this article, we present the current state of art on trained innate immunity occurring as a result of infectious agent induction. Additionally, we discuss the mechanisms of cell reprogramming and the implications for immune response stimulation/manipulation.

Deficient innate immunity, thymopoiesis, and gene expression response to radiation in survivors of childhood acute lymphoblastic leukemia.

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Leung, Wing; Neale, Geoffrey; Behm, Fred; Iyengar, Rekha; Finkelstein, David; Kastan, Michael B; Pui, Ching-Hon

2010-06-01

Survivors of childhood acute lymphoblastic leukemia (ALL) are at an increased risk of developing secondary malignant neoplasms. Radiation and chemotherapy can cause mutations and cytogenetic abnormalities and induce genomic instability. Host immunity and appropriate DNA damage responses are critical inhibitors of carcinogenesis. Therefore, we sought to determine the long-term effects of ALL treatment on immune function and response to DNA damage. Comparative studies on 14 survivors in first complete remission and 16 siblings were conducted. In comparison to siblings on the cells that were involved in adaptive immunity, the patients had either higher numbers (CD19+ B cells and CD4+CD25+ T regulatory cells) or similar numbers (alphabetaT cells and CD45RO+/RA- memory T cells) in the blood. In contrast, patients had lower numbers of all lymphocyte subsets involved in innate immunity (gammadeltaT cells and all NK subsets, including KIR2DL1+ cells, KIR2DL2/L3+ cells, and CD16+ cells), and lower natural cytotoxicity against K562 leukemia cells. Thymopoiesis was lower in patients, as demonstrated by less CD45RO-/RA+ naïve T cell and less SjTREC levels in the blood, whereas the Vbeta spectratype complexity score was similar. Array of gene expression response to low-dose radiation showed that about 70% of the probesets had a reduced response in patients. One of these genes, SCHIP-1, was also among the top-ranked single nucleotide polymorphisms (SNPs) during the whole-genome scanning by SNP microarray analysis. ALL survivors were deficient in innate immunity, thymopoiesis, and DNA damage responses to radiation. These defects may contribute to their increased likelihood of second malignancy. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Music-related reward responses predict episodic memory performance.

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Ferreri, Laura; Rodriguez-Fornells, Antoni

2017-12-01

Music represents a special type of reward involving the recruitment of the mesolimbic dopaminergic system. According to recent theories on episodic memory formation, as dopamine strengthens the synaptic potentiation produced by learning, stimuli triggering dopamine release could result in long-term memory improvements. Here, we behaviourally test whether music-related reward responses could modulate episodic memory performance. Thirty participants rated (in terms of arousal, familiarity, emotional valence, and reward) and encoded unfamiliar classical music excerpts. Twenty-four hours later, their episodic memory was tested (old/new recognition and remember/know paradigm). Results revealed an influence of music-related reward responses on memory: excerpts rated as more rewarding were significantly better recognized and remembered. Furthermore, inter-individual differences in the ability to experience musical reward, measured through the Barcelona Music Reward Questionnaire, positively predicted memory performance. Taken together, these findings shed new light on the relationship between music, reward and memory, showing for the first time that music-driven reward responses are directly implicated in higher cognitive functions and can account for individual differences in memory performance.

Modulation of immune response by bacterial lipopolysaccharides

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Gustavo Aldapa-Vega

2016-08-01

Full Text Available Lipopolysaccharide (LPS is a molecule that is profusely found on the outer membrane of Gram-negative bacteria and is also a potent stimulator of the immune response. As the main molecule on the bacterial surface, is also the most biologically active. The immune response of the host is activated by the recognition of LPS through Toll-like receptor 4 (TLR4 and this receptor-ligand interaction is closely linked to LPS structure. Microorganisms have evolved systems to control the expression and structure of LPS, producing structural variants that are used for modulating the host immune responses during infection. Examples of this include Helicobacter pylori, Francisella tularensis, Chlamydia trachomatis and Salmonella spp. High concentrations of LPS can cause fever, increased heart rate and lead to septic shock and death. However, at relatively low concentrations some LPS are highly active immunomodulators, which can induce non-specific resistance to invading microorganisms. The elucidation of the molecular and cellular mechanisms involved in the recognition of LPS and its structural variants has been fundamental to understand inflammation and is currently a pivotal field of research to understand the innate immune response, inflammation, the complex host-pathogen relationship and has important implications for the rational development of new immunomodulators and adjuvants.

FEATURES OF THE IMMUNE RESPONSE DURING INFECTION AND PROSPECTS FOR THE VACCINES CREATION

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Davidova T.V.

2015-12-01

Full Text Available The influenza virus belongs to the family Orthomyxoviridae and is a major cause of respiratory infections in humans. Each year, influenza viruses cause, according to experts, 3-5 million severe course of the disease and 250 000-500 000 deaths. Influenza A viruses are divided into serotypes based on their surface glycoproteins - known currently 17 subtypes of HA and NA subtypes ten. Upon infection with an influenza virus, both innate and adaptive immune responses are inducing. In recent years the annual seasonal epidemics were causing strains of the virus A (H1N1 and H3N2 and virus B. This may be due to their ability to be unrecognizable virus specific antibodies due to antigenic drift (Figure 1. Seasonal flu vaccine, to be effective, must be updated almost annually, according to new epidemic strains. In this work will discuss various strategies used by influenza viruses to evade innate immune responses and recognition by components of the humoral and cellular immune response, which consequently may result in reduced clearing of the virus and virus-infected cells.The primary targets for influenza viruses are the epithelial cells that line the respiratory tract and which initiate an antiviral immune response upon detection of the virus. The first line of defense is formed by the innate immune system, which is quick but lacks specificity and memory. Innate immunity is formed by physical barriers and innate cellular immune responses. Here, we outline several of the innate defense mechanisms directed against influenza infections. During homeostasis, alveolar macrophages exhibit a relatively quiescent state, producing only low levels of cytokines, and suppress the induction of innate and adaptive immunity. Activated macrophages enhance their pro-inflammatory cytokine response, including IL-6 and TNF-α. Alveolar macrophages have a direct role in limiting viral spread by phagocytosis of apoptotic infected cells and by phagocyte

The immune response to sand fly salivary proteins and its influence on Leishmania immunity

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Regis eGomes

2012-05-01

Full Text Available Leishmaniasis is a vector-borne disease transmitted by bites of phlebotomine sand flies. During Leishmania transmission, sand fly saliva is co-inoculated with parasites into the skin of the mammalian host. Sand fly saliva consists of roughly thirty different salivary proteins, many with known roles linked to blood feeding facilitation. Apart from the anti-hemostatic capacity of saliva, several sand fly salivary proteins have been shown to be immunogenic upon multiple contacts with a mammalian host. Immunization with single immunogenic salivary proteins or exposure to uninfected bites can produce protective immune responses against leishmaniasis. These sand fly salivary proteins induce cellular immune responses and/or antibodies. Antibodies to saliva are not required for protection in a mouse model against leishmaniasis. A strong body of evidence points to the role for saliva-specific T cells producing IFN-γ in the form of a delayed-type hypersensitivity reaction at the bite site as the main protective response. Herein, we review immunity to sand fly salivary proteins in the context of its vector-parasite-host combinations and vaccine potential, as well as some recent advances to shed light on the mechanism of how an immune response to sand fly saliva protects against leishmaniasis.

Modulation of systemic immune responses through commensal gastrointestinal microbiota.

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Kyle M Schachtschneider

Full Text Available Colonization of the gastrointestinal (GI tract is initiated during birth and continually seeded from the individual's environment. Gastrointestinal microorganisms play a central role in developing and modulating host immune responses and have been the subject of investigation over the last decades. Animal studies have demonstrated the impact of GI tract microbiota on local gastrointestinal immune responses; however, the full spectrum of action of early gastrointestinal tract stimulation and subsequent modulation of systemic immune responses is poorly understood. This study explored the utility of an oral microbial inoculum as a therapeutic tool to affect porcine systemic immune responses. For this study a litter of 12 pigs was split into two groups. One group of pigs was inoculated with a non-pathogenic oral inoculum (modulated, while another group (control was not. DNA extracted from nasal swabs and fecal samples collected throughout the study was sequenced to determine the effects of the oral inoculation on GI and respiratory microbial communities. The effects of GI microbial modulation on systemic immune responses were evaluated by experimentally infecting with the pathogen Mycoplasma hyopneumoniae. Coughing levels, pathology, toll-like receptors 2 and 6, and cytokine production were measured throughout the study. Sequencing results show a successful modulation of the GI and respiratory microbiomes through oral inoculation. Delayed type hypersensitivity responses were stronger (p = 0.07, and the average coughing levels and respiratory TNF-α variance were significantly lower in the modulated group (p<0.0001 and p = 0.0153, respectively. The M. hyopneumoniae infection study showed beneficial effects of the oral inoculum on systemic immune responses including antibody production, severity of infection and cytokine levels. These results suggest that an oral microbial inoculation can be used to modulate microbial communities, as well as

Sex hormones and the immune response in humans

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Bouman, Annechien; Heineman, Maas Jan; Faas, Marijke M.

2005-01-01

In addition to their effects on sexual differentiation and reproduction, sex hormones appear to influence the immune system. This results in a sexual dimorphism in the immune response in humans: for instance, females produce more vigorous cellular and more vigorous humoral immune reactions, are more

Bovine immune response to inoculation with Neospora caninum surface antigen SRS2 lipopeptides mimics immune response to infection with live parasites.

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Baszler, Timothy V; Shkap, Varda; Mwangi, Waithaka; Davies, Christopher J; Mathison, Bruce A; Mazuz, Monica; Resnikov, Dror; Fish, Lea; Leibovitch, Benjamin; Staska, Lauren M; Savitsky, Igor

2008-04-01

Infection of cattle with Neospora caninum protozoa, the causative agent of bovine protozoal abortion, results in robust cellular and humoral immune responses, particularly CD4(+) T-lymphocyte activation and gamma interferon (IFN-gamma) secretion. In the present study, N. caninum SRS2 (NcSRS2) T-lymphocyte-epitope-bearing subunits were incorporated into DNA and peptide preparations to assess CD4(+) cell proliferation and IFN-gamma T-lymphocyte-secretion immune responses in cattle with predetermined major histocompatibility complex (MHC) genotypes. In order to optimize dendritic-cell processing, NcSRS2 DNA vaccine was delivered with granulocyte macrophage-colony-stimulating factor and Flt3 ligand adjuvant. The synthesized NcSRS2 peptides were coupled with a palmitic acid molecule (lipopeptide) and delivered with Freund's adjuvant. Cattle vaccinated with NcSRS2 DNA vaccine alone did not induce T-lymphocyte activation or IFN-gamma secretion, whereas subsequent booster inoculation with NcSRS2-lipopeptides induced robust NcSRS2-specific immune responses. Compared to the response in control animals, NcSRS2-lipopeptide-immunized cattle had significantly increased NcSRS2-specific T-lymphocyte proliferation, numbers of IFN-gamma-secreting peripheral blood mononuclear cells, and immunoglobulin G1 (IgG1) and IgG2a antibody levels. The findings show that N. caninum NcSRS2 subunits bearing T-lymphocyte epitopes induced cell-mediated immune responses similar to the protective immune responses previously described against live parasite infection, namely T-lymphocyte activation and IFN-gamma secretion. The findings support the investigation of NcSRS2 immunogens for protection against N. caninum-induced fetal infection and abortion in cattle.

Measles immune suppression: lessons from the macaque model.

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Rory D de Vries

Full Text Available Measles remains a significant childhood disease, and is associated with a transient immune suppression. Paradoxically, measles virus (MV infection also induces robust MV-specific immune responses. Current hypotheses for the mechanism underlying measles immune suppression focus on functional impairment of lymphocytes or antigen-presenting cells, caused by infection with or exposure to MV. We have generated stable recombinant MVs that express enhanced green fluorescent protein, and remain virulent in non-human primates. By performing a comprehensive study of virological, immunological, hematological and histopathological observations made in animals euthanized at different time points after MV infection, we developed a model explaining measles immune suppression which fits with the "measles paradox". Here we show that MV preferentially infects CD45RA(- memory T-lymphocytes and follicular B-lymphocytes, resulting in high infection levels in these populations. After the peak of viremia MV-infected lymphocytes were cleared within days, followed by immune activation and lymph node enlargement. During this period tuberculin-specific T-lymphocyte responses disappeared, whilst strong MV-specific T-lymphocyte responses emerged. Histopathological analysis of lymphoid tissues showed lymphocyte depletion in the B- and T-cell areas in the absence of apoptotic cells, paralleled by infiltration of T-lymphocytes into B-cell follicles and reappearance of proliferating cells. Our findings indicate an immune-mediated clearance of MV-infected CD45RA(- memory T-lymphocytes and follicular B-lymphocytes, which causes temporary immunological amnesia. The rapid oligoclonal expansion of MV-specific lymphocytes and bystander cells masks this depletion, explaining the short duration of measles lymphopenia yet long duration of immune suppression.

The innate immune response during urinary tract infection and pyelonephritis.

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Spencer, John David; Schwaderer, Andrew L; Becknell, Brian; Watson, Joshua; Hains, David S

2014-07-01

Despite its proximity to the fecal flora, the urinary tract is considered sterile. The precise mechanisms by which the urinary tract maintains sterility are not well understood. Host immune responses are critically important in the antimicrobial defense of the urinary tract. During recent years, considerable advances have been made in our understanding of the mechanisms underlying immune homeostasis of the kidney and urinary tract. Dysfunctions in these immune mechanisms may result in acute disease, tissue destruction and overwhelming infection. The objective of this review is to provide an overview of the innate immune response in the urinary tract in response to microbial assault. In doing so, we focus on the role of antimicrobial peptides-a ubiquitous component of the innate immune response.

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

Models for Immune Response and Immune Evasion in MSI Cancer and Lynch Syndrome

OpenAIRE

Özcan, Mine

2017-01-01

Microsatellite-unstable (MSI) cancers occurring in the context of the hereditary Lynch syndrome or as sporadic cancers elicit pronounced tumor-specific immune responses. The pronounced immune response was shown to be closely associated with frameshift peptides (FSP) that are generated as a result of deficiency in DNA mismatch repair system leading to insertion/deletion mutations in coding microsatellites (cMS). FSP neoantigens are long antigenic amino acid stretches that bear m...

Immune and stress responses in oysters with insights on adaptation.

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Guo, Ximing; He, Yan; Zhang, Linlin; Lelong, Christophe; Jouaux, Aude

2015-09-01

Oysters are representative bivalve molluscs that are widely distributed in world oceans. As successful colonizers of estuaries and intertidal zones, oysters are remarkably resilient against harsh environmental conditions including wide fluctuations in temperature and salinity as well as prolonged air exposure. Oysters have no adaptive immunity but can thrive in microbe-rich estuaries as filter-feeders. These unique adaptations make oysters interesting models to study the evolution of host-defense systems. Recent advances in genomic studies including sequencing of the oyster genome have provided insights into oyster's immune and stress responses underlying their amazing resilience. Studies show that the oyster genomes are highly polymorphic and complex, which may be key to their resilience. The oyster genome has a large gene repertoire that is enriched for immune and stress response genes. Thousands of genes are involved in oyster's immune and stress responses, through complex interactions, with many gene families expanded showing high sequence, structural and functional diversity. The high diversity of immune receptors and effectors may provide oysters with enhanced specificity in immune recognition and response to cope with diverse pathogens in the absence of adaptive immunity. Some members of expanded immune gene families have diverged to function at different temperatures and salinities or assumed new roles in abiotic stress response. Most canonical innate immunity pathways are conserved in oysters and supported by a large number of diverse and often novel genes. The great diversity in immune and stress response genes exhibited by expanded gene families as well as high sequence and structural polymorphisms may be central to oyster's adaptation to highly stressful and widely changing environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

Memory T follicular helper CD4 T cells

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J. Scott eHale

2015-02-01

Full Text Available T follicular helper (Tfh cells are the subset of CD4 T helper cells that are required for generation and maintenance of germinal center reactions and the generation of long-lived humoral immunity. This specialized T helper subset provides help to cognate B cells via their expression of CD40 ligand, IL-21, IL-4, and other molecules. Tfh cells are characterized by their expression of the chemokine receptor CXCR5, expression of the transcriptional repressor Bcl6, and their capacity to migrate to the follicle and promote germinal center B cell responses. Until recently, it remained unclear whether Tfh cells differentiated into memory cells and whether they maintain their Tfh commitment at the memory phase. This review will highlight several recent studies that support the idea of Tfh-committed CD4 T cells at the memory stage of the immune response. The implication of these findings is that memory Tfh cells retain their capacity to recall their Tfh-specific effector functions upon reactivation to provide help for B cell responses and play an important role in prime and boost vaccination or during recall responses to infection. The markers that are useful for distinguishing Tfh effector and memory cells, as well as the limitations of using these markers will be discussed. Tfh effector and memory generation, lineage maintenance, and plasticity relative to other T helper lineages (Th1, Th2, Th17, etc will also be discussed. Ongoing discoveries regarding the maintenance and lineage stability versus plasticity of memory Tfh cells will improve strategies that utilize CD4 T cell memory to modulate antibody responses during prime and boost vaccination.

Immunization with avian metapneumovirus harboring chicken Fc induces higher immune responses.

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Paudel, Sarita; Easwaran, Maheswaran; Jang, Hyun; Jung, Ho-Kyoung; Kim, Joo-Hun; Shin, Hyun-Jin

2016-07-15

In this study, we evaluated the immune responses of avian metapneumovirus harboring chicken Fc molecule. Stable Vero cells expressing chicken Fc chimera on its surface (Vero-cFc) were established, and we confirmed that aMPV grown in Vero-cFc incorporated host derived chimera Fc into the aMPV virions. Immunization of chicken with aMPV-cFc induced higher level of antibodies and inflammatory cytokines; (Interferon (IFN)-γ and Interleukin (IL)-1β) compared to those of aMPV. The increased levels of antibodies and inflammatory cytokines in chicken immunized with aMPV-cFc were statistically significantly (p<0.05) to that of aMPV and control. The aMPV-cFc group also generated the highest neutralizing antibody response. After challenges, chickens immunized with aMPV-cFc showed much less pathological signs in nasal turbinates and trachea so that we could confirm aMPV-cFc induced higher protection than that of aMPV. The greater ability of aMPV harboring chicken Fc to that of aMPV presented it as a possible vaccine candidate. Copyright © 2016 Elsevier B.V. All rights reserved.

Probiotics, antibiotics and the immune responses to vaccines.

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Praharaj, Ira; John, Sushil M; Bandyopadhyay, Rini; Kang, Gagandeep

2015-06-19

Orally delivered vaccines have been shown to perform poorly in developing countries. There are marked differences in the structure and the luminal environment of the gut in developing countries resulting in changes in immune and barrier function. Recent studies using newly developed technology and analytic methods have made it increasingly clear that the intestinal microbiota activate a multitude of pathways that control innate and adaptive immunity in the gut. Several hypotheses have been proposed for the underperformance of oral vaccines in developing countries, and modulation of the intestinal microbiota is now being tested in human clinical trials. Supplementation with specific strains of probiotics has been shown to have modulatory effects on intestinal and systemic immune responses in animal models and forms the basis for human studies with vaccines. However, most studies published so far that have evaluated the immune response to vaccines in children and adults have been small and results have varied by age, antigen, type of antibody response and probiotic strain. Use of anthelminthic drugs in children has been shown to possibly increase immunogenicity following oral cholera vaccination, lending further support to the rationale for modulation of the immune response to oral vaccination through the intestinal microbiome. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Evaluation of Mucosal and Systemic Immune Responses Elicited by GPI-0100-Adjuvanted Influenza Vaccine Delivered by Different Immunization Strategies

NARCIS (Netherlands)

Liu, Heng; Patil, Harshad P.; de Vries-Idema, Jacqueline; Wilschut, Jan; Huckriede, Anke

2013-01-01

Vaccines for protection against respiratory infections should optimally induce a mucosal immune response in the respiratory tract in addition to a systemic immune response. However, current parenteral immunization modalities generally fail to induce mucosal immunity, while mucosal vaccine delivery

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.

Initiation of innate immune responses by surveillance of homeostasis perturbations.

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Colaço, Henrique G; Moita, Luis F

2016-07-01

Pathogen recognition, signaling transduction pathways, and effector mechanisms are necessary steps of innate immune responses that play key roles in the early phase of defense and in the stimulation of the later specific response of adaptive immunity. Here, we argue that in addition to the direct recognition of conserved common structural and functional molecular signatures of microorganisms using pattern recognition receptors, hosts can mount an immune response following the sensing of disruption in homeostasis as proximal reporters for infections. Surveillance of disruption of core cellular activities leading to defense responses is a flexible strategy that requires few additional components and that can effectively detect relevant threats. It is likely to be evolutionarily very conserved and ancient because it is operational in organisms that lack pattern recognition triggered immunity. A homeostasis disruption model of immune response initiation and modulation has broad implications for pathophysiology and treatment of disease and might constitute an often overlooked but central component of a comprehensive conceptual framework for innate immunity. © 2016 Federation of European Biochemical Societies.

Neem leaf glycoprotein promotes dual generation of central and effector memory CD8(+) T cells against sarcoma antigen vaccine to induce protective anti-tumor immunity.

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Ghosh, Sarbari; Sarkar, Madhurima; Ghosh, Tithi; Guha, Ipsita; Bhuniya, Avishek; Saha, Akata; Dasgupta, Shayani; Barik, Subhasis; Bose, Anamika; Baral, Rathindranath

2016-03-01

We have previously shown that Neem Leaf Glycoprotein (NLGP) mediates sustained tumor protection by activating host immune response. Now we report that adjuvant help from NLGP predominantly generates CD44(+)CD62L(high)CCR7(high) central memory (TCM; in lymph node) and CD44(+)CD62L(low)CCR7(low) effector memory (TEM; in spleen) CD8(+) T cells of Swiss mice after vaccination with sarcoma antigen (SarAg). Generated TCM and TEM participated either to replenish memory cell pool for sustained disease free states or in rapid tumor eradication respectively. TCM generated after SarAg+NLGP vaccination underwent significant proliferation and IL-2 secretion following SarAg re-stimulation. Furthermore, SarAg+NLGP vaccination helps in greater survival of the memory precursor effector cells at the peak of the effector response and their maintenance as mature memory cells, in comparison to single modality treatment. Such response is corroborated with the reduced phosphorylation of FOXO in the cytosol and increased KLF2 in the nucleus associated with enhanced CD62L, CCR7 expression of lymph node-resident CD8(+) T cells. However, spleen-resident CD8(+) T memory cells show superior efficacy for immediate memory-to-effector cell conversion. The data support in all aspects that SarAg+NLGP demonstrate superiority than SarAg vaccination alone that benefits the host by rapid effector functions whenever required, whereas, central-memory cells are thought to replenish the memory cell pool for ultimate sustained disease free survival till 60 days following post-vaccination tumor inoculation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Respons imun humoral pada pulpitis (Humoral immune response on pulpitis

Directory of Open Access Journals (Sweden)

Trijoedani Widodo

2005-06-01

Full Text Available Pulpitis is an inflammation process on dental pulp tissue, and usually as the continuous of caries. The microorganism in the caries is a potential immunogenic triggering the immune respons, both humoral and celluler immune responses. The aim of this research is to explain the humoral immune response changes in the dental pulp tissues of pulpitis. This research was done on three group samples: Irreversible pulpitis, Reversible pulpitis and sound teeth as the control group. The result showed that there were three pulpitis immunopathologic patterns: the sound teeth immunopathologic pattern showing a low humoral immune response, in a low level of IgG, IgA and IgM, the reversible pulpitis pattern showing that in a higher humoral immune response, IgG and IgA decreased but IgM increased, the irreversible pulpitis pattern showing that IgG and IgM increased, but it couldn't be repaired although it has highly immunity, and it showed an unusually low level of IgA. This low level of IgA meant that irreversible pulpitis had a low mucosal immunity.

Microneedle Array Design Determines the Induction of Protective Memory CD8+ T Cell Responses Induced by a Recombinant Live Malaria Vaccine in Mice

Science.gov (United States)

Carey, John B.; Pearson, Frances E.; Vrdoljak, Anto; McGrath, Marie G.; Crean, Abina M.; Walsh, Patrick T.; Doody, Timothy; O'Mahony, Conor; Hill, Adrian V. S.; Moore, Anne C.

2011-01-01

Background Vaccine delivery into the skin has received renewed interest due to ease of access to the immune system and microvasculature, however the stratum corneum (SC), must be breached for successful vaccination. This has been achieved by removing the SC by abrasion or scarification or by delivering the vaccine intradermally (ID) with traditional needle-and-syringes or with long microneedle devices. Microneedle patch-based transdermal vaccine studies have predominantly focused on antibody induction by inactivated or subunit vaccines. Here, our principal aim is to determine if the design of a microneedle patch affects the CD8+ T cell responses to a malaria antigen induced by a live vaccine. Methodology and Findings Recombinant modified vaccinia virus Ankara (MVA) expressing a malaria antigen was percutaneously administered to mice using a range of silicon microneedle patches, termed ImmuPatch, that differed in microneedle height, density, patch area and total pore volume. We demonstrate that microneedle arrays that have small total pore volumes induce a significantly greater proportion of central memory T cells that vigorously expand to secondary immunization. Microneedle-mediated vaccine priming induced significantly greater T cell immunity post-boost and equivalent protection against malaria challenge compared to ID vaccination. Notably, unlike ID administration, ImmuPatch-mediated vaccination did not induce inflammatory responses at the site of immunization or in draining lymph nodes. Conclusions/Significance This study demonstrates that the design of microneedle patches significantly influences the magnitude and memory of vaccine-induced CD8+ T cell responses and can be optimised for the induction of desired immune responses. Furthermore, ImmuPatch-mediated delivery may be of benefit to reducing unwanted vaccine reactogenicity. In addition to the advantages of low cost and lack of pain, the development of optimised microneedle array designs for the induction

Regulation of immune responses and tolerance: the microRNA perspective

Science.gov (United States)

Chen, Chang-Zheng; Schaffert, Steven; Fragoso, Rita; Loh, Christina

2013-01-01

Summary Much has been learned about the molecular and cellular components critical for the control of immune responses and tolerance. It remains a challenge, however, to control the immune response and tolerance at the system level without causing significant toxicity to normal tissues. Recent studies suggest that microRNA (miRNA) genes, an abundant class of non-coding RNA genes that produce characteristic approximately 22 nucleotides small RNAs, play important roles in immune cells. In this article, we discuss emerging knowledge regarding the functions of miRNA genes in the immune system. We delve into the roles of miRNAs in regulating signaling strength and threshold, homeostasis, and the dynamics of the immune response and tolerance during normal and pathogenic immunological conditions. We also present observations based on analyzes of miR-181 family genes that indicate the potential functions of primary and/ or precursor miRNAs in target recognition and explore the impact of these findings on target identification. Finally, we illustrate that despite the subtle effects of miRNAs on gene expression, miRNAs have the potential to influence the outcomes of normal and pathogenic immune responses by controlling the quantitative and dynamic aspects of immune responses. Tuning miRNA functions in immune cells, through gain- and loss-of-function approaches in mice, may reveal novel approach to restore immune equilibrium from pathogenic conditions, such as autoimmune disease and leukemia, without significant toxicity. PMID:23550642

Regulation of immune responses and tolerance: the microRNA perspective.

Science.gov (United States)

Chen, Chang-Zheng; Schaffert, Steven; Fragoso, Rita; Loh, Christina

2013-05-01

Much has been learned about the molecular and cellular components critical for the control of immune responses and tolerance. It remains a challenge, however, to control the immune response and tolerance at the system level without causing significant toxicity to normal tissues. Recent studies suggest that microRNA (miRNA) genes, an abundant class of non-coding RNA genes that produce characteristic approximately 22 nucleotides small RNAs, play important roles in immune cells. In this article, we discuss emerging knowledge regarding the functions of miRNA genes in the immune system. We delve into the roles of miRNAs in regulating signaling strength and threshold, homeostasis, and the dynamics of the immune response and tolerance during normal and pathogenic immunological conditions. We also present observations based on analyzes of miR-181 family genes that indicate the potential functions of primary and/or precursor miRNAs in target recognition and explore the impact of these findings on target identification. Finally, we illustrate that despite the subtle effects of miRNAs on gene expression, miRNAs have the potential to influence the outcomes of normal and pathogenic immune responses by controlling the quantitative and dynamic aspects of immune responses. Tuning miRNA functions in immune cells, through gain- and loss-of-function approaches in mice, may reveal novel approach to restore immune equilibrium from pathogenic conditions, such as autoimmune disease and leukemia, without significant toxicity. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Chemokine-mediated immune responses in the female genital tract mucosa.

Science.gov (United States)

Deruaz, Maud; Luster, Andrew D

2015-04-01

The genital tract mucosa is the site where sexually transmitted infections gain entry to the host. The immune response at this site is thus critical to provide innate protection against pathogens that are seen for the very first time as well as provide long-term pathogen-specific immunity, which would be required for an effective vaccine against sexually transmitted infection. A finely regulated immune response is therefore required to provide an effective barrier against pathogens without compromising the capacity of the genital tract to allow for successful conception and fetal development. We review recent developments in our understanding of the immune response in the female genital tract to infectious pathogens, using herpes simplex virus-2, human immunodeficiency virus-1 and Chlamydia trachomatis as examples, with a particular focus on the role of chemokines in orchestrating immune cell migration necessary to achieve effective innate and adaptive immune responses in the female genital tract.

Increased TNF-alpha/IFN-gamma/IL-2 and decreased TNF-alpha/IFN-gamma production by central memory T cells are associated with protective responses against bovine tuberculosis following BCG vaccination

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Mayara Fernanda Maggioli

2016-10-01

Full Text Available Central memory T cells (Tcm and polyfunctional CD4 T cell responses contribute to vaccine-elicited protection with both human and bovine tuberculosis (TB; however, their combined role in protective immunity to TB is unclear. To address this question, we evaluated polyfunctional cytokine responses by CD4 T cell effector / memory populations from bacille Calmette Guerin (BCG vaccinated and non-vaccinated calves prior to and after aerosol challenge with virulent Mycobacterium bovis. Polyfunctional cytokine expression patterns in the response by Tcm, effector memory, and effector T cell subsets were similar between BCG-vaccinated and M. bovis-infected calves; only differing in magnitude (i.e., infected > vaccinated. BCG vaccination, however, did alter the kinetics of the ensuing response to virulent M. bovis infection. Early after challenge (three weeks post-infection, non-vaccinates had greater antigen-specific IFN-γ/TNF-α and lesser IFN-γ/TNF-α/IL-2 responses by Tcm cells than did vaccinated animals. Importantly, these differences were also associated with mycobacterial burden upon necropsy. Polyfunctional responses to ESAT-6:CFP10 (antigens not synthesized by BCG strains were detected in memory subsets, as well as in effector cells, as early as three weeks after challenge. These findings suggest that cell fate divergence may occur early after antigen priming in the response to bovine TB and that memory and effector T cells may expand concurrently during the initial phase of the immune response. In summary, robust IFN-γ/TNF-α response by Tcm cells is associated with greater mycobacterial burden while IFN-γ/TNF-α/IL-2 response by Tcm cells are indicative of a protective response to bovine TB.

Risk factors for discordant immune response among HIV-infected ...

African Journals Online (AJOL)

Risk factors for discordant immune response among HIV-infected patients initiating antiretroviral therapy: A retrospective cohort study. ... Multivariate logistic regression models were used to estimate adjusted odds ratios (AORs) to determine associations between discordant immune response and clinical and demographic ...

Sex differences in immune responses: Hormonal effects, antagonistic selection, and evolutionary consequences.

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Roved, Jacob; Westerdahl, Helena; Hasselquist, Dennis

2017-02-01

Males and females differ in both parasite load and the strength of immune responses and these effects have been verified in humans and other vertebrates. Sex hormones act as important modulators of immune responses; the male sex hormone testosterone is generally immunosuppressive while the female sex hormone estrogen tends to be immunoenhancing. Different sets of T-helper cells (Th) have important roles in adaptive immunity, e.g. Th1 cells trigger type 1 responses which are primarily cell-mediated, and Th2 cells trigger type 2 responses which are primarily humoral responses. In our review of the literature, we find that estrogen and progesterone enhance type 2 and suppress type 1 responses in females, whereas testosterone suppresses type 2 responses and shows an inconsistent pattern for type 1 responses in males. When we combine these patterns of generally immunosuppressive and immunoenhancing effects of the sex hormones, our results imply that the sex differences in immune responses should be particularly strong in immune functions associated with type 2 responses, and less pronounced with type 1 responses. In general the hormone-mediated sex differences in immune responses may lead to genetic sexual conflicts on immunity. Thus, we propose the novel hypothesis that sexually antagonistic selection may act on immune genes shared by the sexes, and that the strength of this sexually antagonistic selection should be stronger for type 2- as compared with type 1-associated immune genes. Finally, we put the consequences of sex hormone-induced effects on immune responses into behavioral and ecological contexts, considering social mating system, sexual selection, geographical distribution of hosts, and parasite abundance. Copyright © 2016 Elsevier Inc. All rights reserved.

Long lived haptenspecific memory in the newt, Notophthalmus viridescens

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Ruben, L. N.

1983-01-01

While enhanced long lived secondary humoral immune responses to thymus-dependent (TD) immunogens are known to occur in mammals, they have yet to be characterized in extant ectothermic vertebrates which do not normally generate immunoglobulin isotype diversity. Moreover, examination of memory in such a vertebrate may provide insights into the controversial issue of IgM memory in mammalia. Trinitrophenyl (TNP) conjugated to horse erythrocytes (HRBC) and to lipopolysaccharide (LPS) have been used to study primitive long lived (5 months) memory in the newt, Notophthalmus viridescens. The ability to recall TNP response memory was tested by secondary immunization with hapten conjugates of the same or a different carrier from the one used to initiate the primary response. All responses were monitored by immunocyto-adherence of pooled sensitized spleen cells. While carrier-specific priming was necessary to initiate primary anti-TNP responses when TD carriers (RBC) were used, it was not required when the more rapid secondary responses were tested. No enhanced anti-carrier responses were found. However, carrier-specific suppression of the secondary anti-hapten response was observed. Anamnesis which was both more rapid and intense developed only when TNP-LPS was used as the primary immunogen and anti-hapten memory was recalled with TNP-sheep erythrocytes (SRBC). Daily injections of Cyclosporin A from 1 day before reimmunization, affected the resultant primary (anti-SRBC) and secondary (anti-TNP) responses differentially. Colloidal carbon injection reduced the memory response by one-half. These results suggest that cellular regulatory controls may be involved in newt memory. However, no increase in TNP-specific antigen-binding cell affinity was found in comparisons of primary and secondary responses. Since reimmunization with TNP-LPS failed to produce enhanced responses following TNP-LPS priming, one can conclude that a thymus-independent (TI) carrier of the hapten will

A simple non-linear model of immune response

International Nuclear Information System (INIS)

Gutnikov, Sergei; Melnikov, Yuri

2003-01-01

It is still unknown why the adaptive immune response in the natural immune system based on clonal proliferation of lymphocytes requires interaction of at least two different cell types with the same antigen. We present a simple mathematical model illustrating that the system with separate types of cells for antigen recognition and patogen destruction provides more robust adaptive immunity than the system where just one cell type is responsible for both recognition and destruction. The model is over-simplified as we did not have an intention of describing the natural immune system. However, our model provides a tool for testing the proposed approach through qualitative analysis of the immune system dynamics in order to construct more sophisticated models of the immune systems that exist in the living nature. It also opens a possibility to explore specific features of highly non-linear dynamics in nature-inspired computational paradigms like artificial immune systems and immunocomputing . We expect this paper to be of interest not only for mathematicians but also for biologists; therefore we made effort to explain mathematics in sufficient detail for readers without professional mathematical background

Systems biology of neutrophil differentiation and immune response

DEFF Research Database (Denmark)

Theilgaard-Mönch, Kim; Porse, Bo T; Borregaard, Niels

2005-01-01

Systems biology has emerged as a new scientific field, which aims at investigating biological processes at the genomic and proteomic levels. Recent studies have unravelled aspects of neutrophil differentiation and immune responses at the systems level using high-throughput technologies. These stu......Systems biology has emerged as a new scientific field, which aims at investigating biological processes at the genomic and proteomic levels. Recent studies have unravelled aspects of neutrophil differentiation and immune responses at the systems level using high-throughput technologies....... These studies have identified a plethora of novel effector proteins stored in the granules of neutrophils. In addition, these studies provide evidence that neutrophil differentiation and immune response are governed by a highly coordinated transcriptional programme that regulates cellular fate and function...

A Drosophila immune response against Ras-induced overgrowth

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Thomas Hauling

2014-03-01

Full Text Available Our goal is to characterize the innate immune response against the early stage of tumor development. For this, animal models where genetic changes in specific cells and tissues can be performed in a controlled way have become increasingly important, including the fruitfly Drosophila melanogaster. Many tumor mutants in Drosophila affect the germline and, as a consequence, also the immune system itself, making it difficult to ascribe their phenotype to a specific tissue. Only during the past decade, mutations have been induced systematically in somatic cells to study the control of tumorous growth by neighboring cells and by immune cells. Here we show that upon ectopic expression of a dominant-active form of the Ras oncogene (RasV12, both imaginal discs and salivary glands are affected. Particularly, the glands increase in size, express metalloproteinases and display apoptotic markers. This leads to a strong cellular response, which has many hallmarks of the granuloma-like encapsulation reaction, usually mounted by the insect against larger foreign objects. RNA sequencing of the fat body reveals a characteristic humoral immune response. In addition we also identify genes that are specifically induced upon expression of RasV12. As a proof-of-principle, we show that one of the induced genes (santa-maria, which encodes a scavenger receptor, modulates damage to the salivary glands. The list of genes we have identified provides a rich source for further functional characterization. Our hope is that this will lead to a better understanding of the earliest stage of innate immune responses against tumors with implications for mammalian immunity.

Costs of mounting an immune response during pregnancy in a lizard.

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Meylan, Sandrine; Richard, Murielle; Bauer, Sophie; Haussy, Claudy; Miles, Donald

2013-01-01

Immune defenses are of great benefit to hosts, but reducing the impact of infection by mounting an immune response also entails costs. However, the physiological mechanisms that generate the costs of an immune response remain poorly understood. Moreover, the majority of studies investigating the consequences of an immune challenge in vertebrates have been conducted on mammals and birds. The aim of this study is to investigate the physiological costs of mounting an immune response during gestation in an ectothermic species. Indeed, because ectothermic species are unable to internally regulate their body temperature, the apportionment of resources to homeostatic activities in ectothermic species can differ from that in endothermic species. We conducted this study on the common lizard Zootoca vivipara. We investigated the costs of mounting an immune response by injecting females with sheep red blood cells and quantified the consequences to reproductive performance (litter mass and success) and physiological performance (standard metabolic rate, endurance, and phytohemagglutinin response). In addition, we measured basking behavior. Our analyses revealed that mounting an immune response affected litter mass, physiological performance, and basking behavior. Moreover, we demonstrated that the modulation of an immune challenge is impacted by intrinsic factors, such as body size and condition.

Wallerian degeneration: the innate-immune response to traumatic nerve injury

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Rotshenker Shlomo

2011-08-01

Full Text Available Abstract Traumatic injury to peripheral nerves results in the loss of neural functions. Recovery by regeneration depends on the cellular and molecular events of Wallerian degeneration that injury induces distal to the lesion site, the domain through which severed axons regenerate back to their target tissues. Innate-immunity is central to Wallerian degeneration since innate-immune cells, functions and molecules that are produced by immune and non-immune cells are involved. The innate-immune response helps to turn the peripheral nerve tissue into an environment that supports regeneration by removing inhibitory myelin and by upregulating neurotrophic properties. The characteristics of an efficient innate-immune response are rapid onset and conclusion, and the orchestrated interplay between Schwann cells, fibroblasts, macrophages, endothelial cells, and molecules they produce. Wallerian degeneration serves as a prelude for successful repair when these requirements are met. In contrast, functional recovery is poor when injury fails to produce the efficient innate-immune response of Wallerian degeneration.

Multiscale modeling of mucosal immune responses

Science.gov (United States)

2015-01-01

Computational modeling techniques are playing increasingly important roles in advancing a systems-level mechanistic understanding of biological processes. Computer simulations guide and underpin experimental and clinical efforts. This study presents ENteric Immune Simulator (ENISI), a multiscale modeling tool for modeling the mucosal immune responses. ENISI's modeling environment can simulate in silico experiments from molecular signaling pathways to tissue level events such as tissue lesion formation. ENISI's architecture integrates multiple modeling technologies including ABM (agent-based modeling), ODE (ordinary differential equations), SDE (stochastic modeling equations), and PDE (partial differential equations). This paper focuses on the implementation and developmental challenges of ENISI. A multiscale model of mucosal immune responses during colonic inflammation, including CD4+ T cell differentiation and tissue level cell-cell interactions was developed to illustrate the capabilities, power and scope of ENISI MSM. Background Computational techniques are becoming increasingly powerful and modeling tools for biological systems are of greater needs. Biological systems are inherently multiscale, from molecules to tissues and from nano-seconds to a lifespan of several years or decades. ENISI MSM integrates multiple modeling technologies to understand immunological processes from signaling pathways within cells to lesion formation at the tissue level. This paper examines and summarizes the technical details of ENISI, from its initial version to its latest cutting-edge implementation. Implementation Object-oriented programming approach is adopted to develop a suite of tools based on ENISI. Multiple modeling technologies are integrated to visualize tissues, cells as well as proteins; furthermore, performance matching between the scales is addressed. Conclusion We used ENISI MSM for developing predictive multiscale models of the mucosal immune system during gut

Multiscale modeling of mucosal immune responses.

Science.gov (United States)

Mei, Yongguo; Abedi, Vida; Carbo, Adria; Zhang, Xiaoying; Lu, Pinyi; Philipson, Casandra; Hontecillas, Raquel; Hoops, Stefan; Liles, Nathan; Bassaganya-Riera, Josep

2015-01-01

Computational techniques are becoming increasingly powerful and modeling tools for biological systems are of greater needs. Biological systems are inherently multiscale, from molecules to tissues and from nano-seconds to a lifespan of several years or decades. ENISI MSM integrates multiple modeling technologies to understand immunological processes from signaling pathways within cells to lesion formation at the tissue level. This paper examines and summarizes the technical details of ENISI, from its initial version to its latest cutting-edge implementation. Object-oriented programming approach is adopted to develop a suite of tools based on ENISI. Multiple modeling technologies are integrated to visualize tissues, cells as well as proteins; furthermore, performance matching between the scales is addressed. We used ENISI MSM for developing predictive multiscale models of the mucosal immune system during gut inflammation. Our modeling predictions dissect the mechanisms by which effector CD4+ T cell responses contribute to tissue damage in the gut mucosa following immune dysregulation.Computational modeling techniques are playing increasingly important roles in advancing a systems-level mechanistic understanding of biological processes. Computer simulations guide and underpin experimental and clinical efforts. This study presents ENteric Immune Simulator (ENISI), a multiscale modeling tool for modeling the mucosal immune responses. ENISI's modeling environment can simulate in silico experiments from molecular signaling pathways to tissue level events such as tissue lesion formation. ENISI's architecture integrates multiple modeling technologies including ABM (agent-based modeling), ODE (ordinary differential equations), SDE (stochastic modeling equations), and PDE (partial differential equations). This paper focuses on the implementation and developmental challenges of ENISI. A multiscale model of mucosal immune responses during colonic inflammation, including CD4+ T

Suppressive influences in the immune response to cancer.

Science.gov (United States)

Bronte, Vincenzo; Mocellin, Simone

2009-01-01

Although much evidence has been gathered demonstrating that immune effectors can play a significant role in controlling tumor growth under natural conditions or in response to therapeutic manipulation, it is clear that malignant cells do evade immune surveillance in most cases. Considering that anticancer active specific immunotherapy seems to have reached a plateau of results and that currently no vaccination regimen is indicated as a standard anticancer therapy, the dissection of the molecular events underlying tumor immune escape is the necessary condition to make anticancer vaccines a therapeutic weapon effective enough to be implemented in the routine clinical setting. Recent years have witnessed significant advances in our understanding of the molecular mechanisms underlying tumor immune escape. These mechanistic insights are fostering the development of rationally designed therapeutics aimed to revert the immunosuppressive circuits that undermine an effective antitumor immune response. In this review, the best characterized mechanisms that allow cancer cells to evade immune surveillance are overviewed and the most debated controversies constellating this complex field are highlighted.

Lessons Learned from Protective Immune Responses to Optimize Vaccines against Cryptosporidiosis.

Science.gov (United States)

Lemieux, Maxime W; Sonzogni-Desautels, Karine; Ndao, Momar

2017-12-24

In developing countries, cryptosporidiosis causes moderate-to-severe diarrhea and kills thousands of infants and toddlers annually. Drinking and recreational water contaminated with Cryptosporidium spp. oocysts has led to waterborne outbreaks in developed countries. A competent immune system is necessary to clear this parasitic infection. A better understanding of the immune responses required to prevent or limit infection by this protozoan parasite is the cornerstone of development of an effective vaccine. In this light, lessons learned from previously developed vaccines against Cryptosporidium spp. are at the foundation for development of better next-generation vaccines. In this review, we summarize the immune responses elicited by naturally and experimentally-induced Cryptosporidium spp. infection and by several experimental vaccines in various animal models. Our aim is to increase awareness about the immune responses that underlie protection against cryptosporidiosis and to encourage promotion of these immune responses as a key strategy for vaccine development. Innate and mucosal immunity will be addressed as well as adaptive immunity, with an emphasis on the balance between T H 1/T H 2 immune responses. Development of more effective vaccines against cryptosporidiosis is needed to prevent Cryptosporidium spp.-related deaths in infants and toddlers in developing countries.

Co-administration of α-GalCer analog and TLR4 agonist induces robust CD8+ T-cell responses to PyCS protein and WT-1 antigen and activates memory-like effector NKT cells

Science.gov (United States)

Coelho-dos-Reis, Jordana G.; Huang, Jing; Tsao, Tiffany; Pereira, Felipe V.; Funakoshi, Ryota; Nakajima, Hiroko; Sugiyama, Haruo; Tsuji, Moriya

2016-01-01

In the present study, the combined adjuvant effect of 7DW8-5, a potent α-GalCer-analog, and monophosphoryl lipid A (MPLA), a TLR4 agonist, on the induction of vaccine-induced CD8+ T-cell responses and protective immunity was evaluated. Mice were immunized with peptides corresponding to the CD8+ T-cell epitopes of a malaria antigen, a circumsporozoite protein of Plasmodium yoelii, and a tumor antigen, a Wilms Tumor antigen-1 (WT-1), together with 7DW8-5 and MPLA, as an adjuvant. These immunization regimens were able to induce higher levels of CD8+ T-cell responses and, ultimately, enhanced levels of protection against malaria and tumor challenges compared to the levels induced by immunization with peptides mixed with 7DW8-5 or MPLA alone. Co-administration of 7DW8-5 and MPLA induces activation of memory-like effector natural killer T (NKT) cells, i.e. CD44+CD62L−NKT cells. Our study indicates that 7DW8-5 greatly enhances important synergistic pathways associated to memory immune responses when co-administered with MPLA, thus rendering this combination of adjuvants a novel vaccine adjuvant formulation. PMID:27132023

Characterisation of immune responses in healthy foals when a multivalent vaccine protocol was initiated at age 90 or 180 days.

Science.gov (United States)

Davis, E G; Bello, N M; Bryan, A J; Hankins, K; Wilkerson, M

2015-11-01

Protection from infectious disease requires antigen-specific immunity. In foals, most vaccine protocols are delayed until 6 months to avoid maternal antibody interference. Susceptibility to disease may exist prior to administration of vaccination at age 4-6 months. The aim of this investigation was to characterise immune activation among healthy foals in response to a multivalent vaccine protocol and compare immune responses when foals were vaccinated at age either 90 or 180 days. Randomised block design. Twelve healthy foals with colostral transfer were blocked for age and randomly assigned to vaccination at age 90 days (treatment) or at age 180 days (control). Vaccination protocols included a 3-dose series and booster vaccine administered at age 11 months. Immune response following vaccination at age 90 or 180 days was comparable for several measures of cellular immunity. Antigen specific CD4+ and CD8+ expression of interleukin-4, interferon-γ and granzyme B to eastern equine encephalomyelitis, western equine encephalomyelitis, West Nile virus, tetanus toxoid, equine influenza and equine herpesvirus-1/4 antigens were evident for both groups 30 days after initial vaccine and at age 344 days. Both groups showed a significant increase in antigen-specific immunoglobulin G expression following booster vaccine at age 11 months, thereby indicating memory immune responses. The data presented in this report demonstrate that young foals are capable of immune activation following a 3-dose series with a multivalent vaccine, despite presence of maternal antibodies. Although immune activation does not automatically confer protection, several of the immune indicators measured showed comparable expression in foals vaccinated at 3 months relative to control foals vaccinated at age 6 months. In high-risk situations where immunity may be required earlier than following a conventional vaccine series, our data provide evidence that foals respond to immunisation initiated at 3 months

Orchestration of pulmonary T cell immunity during Mycobacterium tuberculosis infection: immunity interruptus

Science.gov (United States)

Behar, Samuel M.; Carpenter, Stephen M.; Booty, Matthew G.; Barber, Daniel L.; Jayaraman, Pushpa

2014-01-01

Despite the introduction almost a century ago of Mycobacterium bovis BCG (BCG), an attenuated form of M. bovis that is used as a vaccine against Mycobacterium tuberculosis, tuberculosis remains a global health threat and kills more than 1.5 million people each year. This is mostly because BCG fails to prevent pulmonary disease – the contagious form of tuberculosis. Although there have been significant advances in understanding how the immune system responds to infection, the qualities that define protective immunity against M. tuberculosis remain poorly characterized. The ability to predict who will maintain control over the infection and who will succumb to clinical disease would revolutionize our approach to surveillance, control, and treatment. Here we review the current understanding of pulmonary T cell responses following M. tuberculosis infection. While infection elicits a strong immune response that contains infection, M. tuberculosis evades eradication. Traditionally, its intracellular lifestyle and alteration of macrophage function are viewed as the dominant mechanisms of evasion. Now we appreciate that chronic inflammation leads to T cell dysfunction. While this may arise as the host balances the goals of bacterial sterilization and avoidance of tissue damage, it is becoming clear that T cell dysfunction impairs host resistance. Defining the mechanisms that lead to T cell dysfunction is crucial as memory T cell responses are likely to be subject to the same subject to the same pressures. Thus, success of T cell based vaccines is predicated on memory T cells avoiding exhaustion while at the same time not promoting overt tissue damage. PMID:25311810

The Role of the Immune Response in Merkel Cell Carcinoma

International Nuclear Information System (INIS)

Triozzi, Pierre L.; Fernandez, Anthony P.

2013-01-01

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer. The Merkel cell polyomavirus (MCPyV) is implicated in its pathogenesis. Immune mechanisms are also implicated. Patients who are immunosuppressed have an increased risk. There is evidence that high intratumoral T-cell counts and immune transcripts are associated with favorable survival. Spontaneous regressions implicate immune effector mechanisms. Immunogenicity is also supported by observation of autoimmune paraneoplastic syndromes. Case reports suggest that immune modulation, including reduction of immune suppression, can result in tumor regression. The relationships between MCPyV infection, the immune response, and clinical outcome, however, remain poorly understood. Circulating antibodies against MCPyV antigens are present in most individuals. MCPyV-reactive T cells have been detected in both MCC patients and control subjects. High intratumoral T-cell counts are also associated with favorable survival in MCPyV-negative MCC. That the immune system plays a central role in preventing and controlling MCC is supported by several observations. MCCs often develop, however, despite the presence of humoral and cellular immune responses. A better understanding on how MCPyV and MCC evade the immune response will be necessary to develop effective immunotherapies

The Role of the Immune Response in Merkel Cell Carcinoma

Energy Technology Data Exchange (ETDEWEB)

Triozzi, Pierre L., E-mail: triozzp@ccf.org [Taussig Cancer Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Fernandez, Anthony P. [Departments of Dermatology and Anatomic Pathology, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195 (United States)

2013-02-28

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer. The Merkel cell polyomavirus (MCPyV) is implicated in its pathogenesis. Immune mechanisms are also implicated. Patients who are immunosuppressed have an increased risk. There is evidence that high intratumoral T-cell counts and immune transcripts are associated with favorable survival. Spontaneous regressions implicate immune effector mechanisms. Immunogenicity is also supported by observation of autoimmune paraneoplastic syndromes. Case reports suggest that immune modulation, including reduction of immune suppression, can result in tumor regression. The relationships between MCPyV infection, the immune response, and clinical outcome, however, remain poorly understood. Circulating antibodies against MCPyV antigens are present in most individuals. MCPyV-reactive T cells have been detected in both MCC patients and control subjects. High intratumoral T-cell counts are also associated with favorable survival in MCPyV-negative MCC. That the immune system plays a central role in preventing and controlling MCC is supported by several observations. MCCs often develop, however, despite the presence of humoral and cellular immune responses. A better understanding on how MCPyV and MCC evade the immune response will be necessary to develop effective immunotherapies.

Early-life inflammation, immune response and ageing.

Science.gov (United States)

Khan, Imroze; Agashe, Deepa; Rolff, Jens

2017-03-15

Age-related diseases are often attributed to immunopathology, which results in self-damage caused by an inappropriate inflammatory response. Immunopathology associated with early-life inflammation also appears to cause faster ageing, although we lack direct experimental evidence for this association. To understand the interactions between ageing, inflammation and immunopathology, we used the mealworm beetle Tenebrio molitor as a study organism. We hypothesized that phenoloxidase, an important immune effector in insect defence, may impose substantial immunopathological costs by causing tissue damage to Malpighian tubules (MTs; functionally equivalent to the human kidney), in turn accelerating ageing. In support of this hypothesis, we found that RNAi knockdown of phenoloxidase (PO) transcripts in young adults possibly reduced inflammation-induced autoreactive tissue damage to MTs, and increased adult lifespan. Our work thus suggests a causative link between immunopathological costs of early-life inflammation and faster ageing. We also reasoned that if natural selection weakens with age, older individuals should display increased immunopathological costs associated with an immune response. Indeed, we found that while old infected individuals cleared infection faster than young individuals, possibly they also displayed exacerbated immunopathological costs (larger decline in MT function) and higher post-infection mortality. RNAi-mediated knockdown of PO response partially rescued MTs function in older beetles and resulted in increased lifespan after infection. Taken together, our data are consistent with a direct role of immunopathological consequences of immune response during ageing in insects. Our work is also the first report that highlights the pervasive role of tissue damage under diverse contexts of ageing and immune response. © 2017 The Author(s).

Adaptive Immunity against Streptococcus pyogenes in Adults Involves Increased IFN-gamma and IgG3 Responses Compared with Children

DEFF Research Database (Denmark)

Mortensen, Rasmus; Nissen, Thomas Norrelykke; Blauenfeldt, Thomas

2015-01-01

Each year, millions of people are infected with Streptococcus pyogenes, leading to an estimated 500,000 annual deaths worldwide. For unknown reasons, school-aged children have substantially higher infection rates than adults. The goal for this study was to provide, to our knowledge, the first det...... cellular memory response in combination with IgG1/IgG3-dominated humoral immunity that increase with age. The significance of these data regarding both the increased GAS infection rate in children and the development of protective GAS vaccines is discussed.......Each year, millions of people are infected with Streptococcus pyogenes, leading to an estimated 500,000 annual deaths worldwide. For unknown reasons, school-aged children have substantially higher infection rates than adults. The goal for this study was to provide, to our knowledge, the first...... detailed characterization of the human adaptive immune response against S. pyogenes in both children and adults. We report that all adults in our study, as well as most children, showed immunity against the two conserved group A streptococci (GAS) Ags, streptococcal C5a peptidase and immunogenic secreted...

17D yellow fever vaccine elicits comparable long-term immune responses in healthy individuals and immune-compromised patients

NARCIS (Netherlands)

Wieten, R. W.; Goorhuis, A.; Jonker, E. F. F.; de Bree, G. J.; de Visser, A. W.; van Genderen, P. J. J.; Remmerswaal, E. B. M.; ten Berge, I. J. M.; Visser, L. G.; Grobusch, M. P.; van Leeuwen, E. M. M.

2016-01-01

The 17D live attenuated yellow fever (YF) vaccine is contra-indicated in immune-compromised individuals and may elicit a suboptimal immunologic response. The aim of this study is to assess whether long-term immune responses against the YF vaccine are impaired in immune-compromised patients. Fifteen

Ovine model for studying pulmonary immune responses

International Nuclear Information System (INIS)

Joel, D.D.; Chanana, A.D.

1984-01-01

Anatomical features of the sheep lung make it an excellent model for studying pulmonary immunity. Four specific lung segments were identified which drain exclusively to three separate lymph nodes. One of these segments, the dorsal basal segment of the right lung, is drained by the caudal mediastinal lymph node (CMLN). Cannulation of the efferent lymph duct of the CMLN along with highly localized intrabronchial instillation of antigen provides a functional unit with which to study factors involved in development of pulmonary immune responses. Following intrabronchial immunization there was an increased output of lymphoblasts and specific antibody-forming cells in efferent CMLN lymph. Continuous divergence of efferent lymph eliminated the serum antibody response but did not totally eliminate the appearance of specific antibody in fluid obtained by bronchoalveolar lavage. In these studies localized immunization of the right cranial lobe served as a control. Efferent lymphoblasts produced in response to intrabronchial antigen were labeled with 125 I-iododeoxyuridine and their migrational patterns and tissue distribution compared to lymphoblasts obtained from the thoracic duct. The results indicated that pulmonary immunoblasts tend to relocate in lung tissue and reappear with a higher specific activity in pulmonary lymph than in thoracic duct lymph. The reverse was observed with labeled intestinal lymphoblasts. 35 references, 2 figures, 3 tables

Ovine model for studying pulmonary immune responses

Energy Technology Data Exchange (ETDEWEB)

Joel, D.D.; Chanana, A.D.

1984-11-25

Anatomical features of the sheep lung make it an excellent model for studying pulmonary immunity. Four specific lung segments were identified which drain exclusively to three separate lymph nodes. One of these segments, the dorsal basal segment of the right lung, is drained by the caudal mediastinal lymph node (CMLN). Cannulation of the efferent lymph duct of the CMLN along with highly localized intrabronchial instillation of antigen provides a functional unit with which to study factors involved in development of pulmonary immune responses. Following intrabronchial immunization there was an increased output of lymphoblasts and specific antibody-forming cells in efferent CMLN lymph. Continuous divergence of efferent lymph eliminated the serum antibody response but did not totally eliminate the appearance of specific antibody in fluid obtained by bronchoalveolar lavage. In these studies localized immunization of the right cranial lobe served as a control. Efferent lymphoblasts produced in response to intrabronchial antigen were labeled with /sup 125/I-iododeoxyuridine and their migrational patterns and tissue distribution compared to lymphoblasts obtained from the thoracic duct. The results indicated that pulmonary immunoblasts tend to relocate in lung tissue and reappear with a higher specific activity in pulmonary lymph than in thoracic duct lymph. The reverse was observed with labeled intestinal lymphoblasts. 35 references, 2 figures, 3 tables.

Therapeutic immunization with HIV-1 Tat reduces immune activation and loss of regulatory T-cells and improves immune function in subjects on HAART.

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Barbara Ensoli

2010-11-01

Full Text Available Although HAART suppresses HIV replication, it is often unable to restore immune homeostasis. Consequently, non-AIDS-defining diseases are increasingly seen in treated individuals. This is attributed to persistent virus expression in reservoirs and to cell activation. Of note, in CD4(+ T cells and monocyte-macrophages of virologically-suppressed individuals, there is continued expression of multi-spliced transcripts encoding HIV regulatory proteins. Among them, Tat is essential for virus gene expression and replication, either in primary infection or for virus reactivation during HAART, when Tat is expressed, released extracellularly and exerts, on both the virus and the immune system, effects that contribute to disease maintenance. Here we report results of an ad hoc exploratory interim analysis (up to 48 weeks on 87 virologically-suppressed HAART-treated individuals enrolled in a phase II randomized open-label multicentric clinical trial of therapeutic immunization with Tat (ISS T-002. Eighty-eight virologically-suppressed HAART-treated individuals, enrolled in a parallel prospective observational study at the same sites (ISS OBS T-002, served for intergroup comparison. Immunization with Tat was safe, induced durable immune responses, and modified the pattern of CD4(+ and CD8(+ cellular activation (CD38 and HLA-DR together with reduction of biochemical activation markers and persistent increases of regulatory T cells. This was accompanied by a progressive increment of CD4(+ T cells and B cells with reduction of CD8(+ T cells and NK cells, which were independent from the type of antiretroviral regimen. Increase in central and effector memory and reduction in terminally-differentiated effector memory CD4(+ and CD8(+ T cells were accompanied by increases of CD4(+ and CD8(+ T cell responses against Env and recall antigens. Of note, more immune-compromised individuals experienced greater therapeutic effects. In contrast, these changes were opposite

Immune response in the lungs following oral immunization with bacterial lysates of respiratory pathogens.

OpenAIRE

Ruedl, C; Frühwirth, M; Wick, G; Wolf, H

1994-01-01

We have investigated the local immune response of the BALB/c mouse respiratory tract after oral immunization with a bacterial lysate of seven common respiratory pathogens. After two immunization on five consecutive days, we examined the immunoglobulin (immunoglobulin G [IgG], IgM, and IgA) secretion rates of cells isolated from the lungs and compared them with those of spleen cells of orally immunized and nonimmunized animals by using a new test system based on time-resolved fluorescence. The...

Longitudinal multiparameter single-cell analysis of macaques immunized with pneumococcal protein-conjugated or unconjugated polysaccharide vaccines reveals distinct antigen specific memory B cell repertoires.

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Bin Jia

Full Text Available The efficacy of protein-conjugated pneumococcal polysaccharide vaccines has been well characterized for children. The level of protection conferred by unconjugated polysaccharide vaccines remains less clear, particularly for elderly individuals who have had prior antigenic experience through immunization with unconjugated polysaccharide vaccines or natural exposure to Streptococcus pneumoniae.We compared the magnitude, diversity and genetic biases of antigen-specific memory B cells in two groups of adult cynomolgus macaques that were immunized with a 7-valent conjugated vaccine and boosted after five years with either a 13-valent pneumococcal polysaccharide conjugate vaccine (13vPnC or a 23-valent unconjugated pneumococcal polysaccharide vaccine (23vPS using microengraving (a single-cell analysis method and single-cell RT-PCR.Seven days after boosting, the mean frequency of antigen-specific memory B cells was significantly increased in macaques vaccinated with 13vPnC compared to those receiving 23vPS. The 13vPnC-vaccinated macaques also exhibited a more even distribution of antibody specificities to four polysaccharides in the vaccine (PS4, 6B, 14, 23F that were examined. However, single-cell analysis of the antibody variable region sequences from antigen-specific B cells elicited by unconjugated and conjugated vaccines indicated that both the germline gene segments forming the heavy chains and the average lengths of the Complementary Determining Region 3 (CDR3 were similar.Our results confirm that distinctive differences can manifest between antigen-specific memory B cell repertoires in nonhuman primates immunized with conjugated and unconjugated pneumococcal polysaccharide vaccines. The study also supports the notion that the conjugated vaccines have a favorable profile in terms of both the frequency and breadth of the anamnestic response among antigen-specific memory B cells.

Innate Immune Responses in Leprosy

Science.gov (United States)

Pinheiro, Roberta Olmo; Schmitz, Veronica; Silva, Bruno Jorge de Andrade; Dias, André Alves; de Souza, Beatriz Junqueira; de Mattos Barbosa, Mayara Garcia; de Almeida Esquenazi, Danuza; Pessolani, Maria Cristina Vidal; Sarno, Euzenir Nunes

2018-01-01

Leprosy is an infectious disease that may present different clinical forms depending on host immune response to Mycobacterium leprae. Several studies have clarified the role of various T cell populations in leprosy; however, recent evidences suggest that local innate immune mechanisms are key determinants in driving the disease to its different clinical manifestations. Leprosy is an ideal model to study the immunoregulatory role of innate immune molecules and its interaction with nervous system, which can affect homeostasis and contribute to the development of inflammatory episodes during the course of the disease. Macrophages, dendritic cells, neutrophils, and keratinocytes are the major cell populations studied and the comprehension of the complex networking created by cytokine release, lipid and iron metabolism, as well as antimicrobial effector pathways might provide data that will help in the development of new strategies for leprosy management. PMID:29643852

A Cholera Conjugate Vaccine Containing O-specific Polysaccharide (OSP of V. cholerae O1 Inaba and Recombinant Fragment of Tetanus Toxin Heavy Chain (OSP:rTTHc Induces Serum, Memory and Lamina Proprial Responses against OSP and Is Protective in Mice.

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Md Abu Sayeed

Full Text Available Vibrio cholerae is the cause of cholera, a severe watery diarrhea. Protection against cholera is serogroup specific. Serogroup specificity is defined by the O-specific polysaccharide (OSP component of lipopolysaccharide (LPS.Here we describe a conjugate vaccine for cholera prepared via squaric acid chemistry from the OSP of V. cholerae O1 Inaba strain PIC018 and a recombinant heavy chain fragment of tetanus toxin (OSP:rTTHc. We assessed a range of vaccine doses based on the OSP content of the vaccine (10-50 μg, vaccine compositions varying by molar loading ratio of OSP to rTTHc (3:1, 5:1, 10:1, effect of an adjuvant, and route of immunization.Immunized mice developed prominent anti-OSP and anti-TT serum IgG responses, as well as vibriocidal antibody and memory B cell responses following intramuscular or intradermal vaccination. Mice did not develop anti-squarate responses. Intestinal lamina proprial IgA responses targeting OSP occurred following intradermal vaccination. In general, we found comparable immune responses in mice immunized with these variations, although memory B cell and vibriocidal responses were blunted in mice receiving the highest dose of vaccine (50 μg. We found no appreciable change in immune responses when the conjugate vaccine was administered in the presence or absence of immunoadjuvant alum. Administration of OSP:rTTHc resulted in 55% protective efficacy in a mouse survival cholera challenge model.We report development of an Inaba OSP:rTTHc conjugate vaccine that induces memory responses and protection against cholera in mice. Development of an effective cholera conjugate vaccine that induces high level and long-term immune responses against OSP would be beneficial, especially in young children who respond poorly to polysaccharide antigens.

Preexisting Salmonella-specific immunity interferes with the subsequent development of immune responses against the Salmonella strains delivering H9N2 hemagglutinin.

Science.gov (United States)

Hajam, Irshad Ahmed; Lee, John Hwa

2017-06-01

Recombinant Salmonella strains expressing foreign heterologous antigens have been extensively studied as promising live vaccine delivery vehicles. In this study, we constructed attenuated smooth (S-HA) and rough (R-HA) Salmonella strains expressing hemagglutinin (HA) of H9N2, a low pathogenic avian influenza A virus. We then investigated the HA-specific immune responses following oral immunization with either S-HA or R-HA strain in chicken model. We further examined the effects of the preexisting anti-Salmonella immunity on the subsequent elicitation of the HA and the Salmonella ompA specific immune responses. Our results showed that primary immunization with either the S-HA or the R-HA strain elicited comparable HA-specific immune responses and the responses were significantly (pSalmonella vector control. When chickens were pre-immunized with the smooth Salmonella carrier alone and then vaccinated with either S-HA or R-HA strain 3, 6 and 9 weeks later, respectively, significant reductions were seen for HA-specific immune responses at week 6, a point which corresponded to the peak of the primary Salmonella-specific antibody responses. No reductions were seen at week 3 and 9, albeit, the HA-specific immune responses were boosted at week 9, a point which corresponded to the lowest primary Salmonella-specific antibody responses. The ompA recall responses remain refractory at week 3 and 6 following deliberate immunization with the carrier strain, but were significantly (pSalmonella immunity inhibits antigen-specific immune responses and this effect could be avoided by carefully selecting the time point when carrier-specific immune responses are relatively low. Copyright © 2017 Elsevier B.V. All rights reserved.

Circumvention of MHC class II restriction by genetic immunization.

Science.gov (United States)

Schuler, K; Lu, C; Chang, H D; Croft, M; Zanetti, M; Gerloni, M

2001-11-12

The fate of T cell responses to peptide-based vaccination is subject to constraints by the major histocompatibility complex (MHC), MHC restriction. Using as a model system of T and B cell epitopes from the circumsporozoite protein of Plasmodium falciparum malaria parasite, we show that vaccination by somatic transgene immunization readily primes Balb/c mice (H-2(d)) a strain previously reported to be non-responder to immunization with a synthetic peptide vaccine encompassing these epitopes. Following genetic vaccination Balb/c mice developed a primary T cell response comparable to that of the responder strain C57Bl/6 (H-2(b)). Following booster immunization on day 45 Balb/c mice responded with a typical T cell memory response. Priming induced the formation of specific antibodies, which rose sharply after booster immunization. These findings suggests that genetic immunization can circumvent MHC class II restriction.

Innate Immune Responses of Drosophila melanogaster Are Altered by Spaceflight

Science.gov (United States)

Marcu, Oana; Lera, Matthew P.; Sanchez, Max E.; Levic, Edina; Higgins, Laura A.; Shmygelska, Alena; Fahlen, Thomas F.; Nichol, Helen; Bhattacharya, Sharmila

2011-01-01

Alterations and impairment of immune responses in humans present a health risk for space exploration missions. The molecular mechanisms underpinning innate immune defense can be confounded by the complexity of the acquired immune system of humans. Drosophila (fruit fly) innate immunity is simpler, and shares many similarities with human innate immunity at the level of molecular and genetic pathways. The goals of this study were to elucidate fundamental immune processes in Drosophila affected by spaceflight and to measure host-pathogen responses post-flight. Five containers, each containing ten female and five male fruit flies, were housed and bred on the space shuttle (average orbit altitude of 330.35 km) for 12 days and 18.5 hours. A new generation of flies was reared in microgravity. In larvae, the immune system was examined by analyzing plasmatocyte number and activity in culture. In adults, the induced immune responses were analyzed by bacterial clearance and quantitative real-time polymerase chain reaction (qPCR) of selected genes following infection with E. coli. The RNA levels of relevant immune pathway genes were determined in both larvae and adults by microarray analysis. The ability of larval plasmatocytes to phagocytose E. coli in culture was attenuated following spaceflight, and in parallel, the expression of genes involved in cell maturation was downregulated. In addition, the level of constitutive expression of pattern recognition receptors and opsonins that specifically recognize bacteria, and of lysozymes, antimicrobial peptide (AMP) pathway and immune stress genes, hallmarks of humoral immunity, were also reduced in larvae. In adults, the efficiency of bacterial clearance measured in vivo following a systemic infection with E. coli post-flight, remained robust. We show that spaceflight altered both cellular and humoral immune responses in Drosophila and that the disruption occurs at multiple interacting pathways. PMID:21264297

Innate immune responses of Drosophila melanogaster are altered by spaceflight.

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Oana Marcu

2011-01-01

Full Text Available Alterations and impairment of immune responses in humans present a health risk for space exploration missions. The molecular mechanisms underpinning innate immune defense can be confounded by the complexity of the acquired immune system of humans. Drosophila (fruit fly innate immunity is simpler, and shares many similarities with human innate immunity at the level of molecular and genetic pathways. The goals of this study were to elucidate fundamental immune processes in Drosophila affected by spaceflight and to measure host-pathogen responses post-flight. Five containers, each containing ten female and five male fruit flies, were housed and bred on the space shuttle (average orbit altitude of 330.35 km for 12 days and 18.5 hours. A new generation of flies was reared in microgravity. In larvae, the immune system was examined by analyzing plasmatocyte number and activity in culture. In adults, the induced immune responses were analyzed by bacterial clearance and quantitative real-time polymerase chain reaction (qPCR of selected genes following infection with E. coli. The RNA levels of relevant immune pathway genes were determined in both larvae and adults by microarray analysis. The ability of larval plasmatocytes to phagocytose E. coli in culture was attenuated following spaceflight, and in parallel, the expression of genes involved in cell maturation was downregulated. In addition, the level of constitutive expression of pattern recognition receptors and opsonins that specifically recognize bacteria, and of lysozymes, antimicrobial peptide (AMP pathway and immune stress genes, hallmarks of humoral immunity, were also reduced in larvae. In adults, the efficiency of bacterial clearance measured in vivo following a systemic infection with E. coli post-flight, remained robust. We show that spaceflight altered both cellular and humoral immune responses in Drosophila and that the disruption occurs at multiple interacting pathways.

Quantitating cellular immune responses to cancer vaccines.

Science.gov (United States)

Lyerly, H Kim

2003-06-01

While the future of immunotherapy in the treatment of cancer is promising, it is difficult to compare the various approaches because monitoring assays have not been standardized in approach or technique. Common assays for measuring the immune response need to be established so that these assays can one day serve as surrogate markers for clinical response. Assays that accurately detect and quantitate T-cell-mediated, antigen-specific immune responses are particularly desired. However, to date, increases in the number of cytotoxic T cells through immunization have not been correlated with clinical tumor regression. Ideally, then, a T-cell assay not only needs to be sensitive, specific, reliable, reproducible, simple, and quick to perform, it must also demonstrate close correlation with clinical outcome. Assays currently used to measure T-cell response are delayed-type hypersensitivity testing, flow cytometry using peptide major histocompatibility complex tetramers, lymphoproliferation assay, enzyme-linked immunosorbant assay, enzyme-linked immunospot assay, cytokine flow cytometry, direct cytotoxicity assay, measurement of cytokine mRNA by quantitative reverse transcriptase polymerase chain reaction, and limiting dilution analysis. The purpose of this review is to describe the attributes of each test and compare their advantages and disadvantages.

Immune responses in cattle vaccinated with gamma-irradiated Anaplasma marginale

International Nuclear Information System (INIS)

Sharma, S.P.; Bansal, G.C.

1986-01-01

The infectivity and immunogenecity of gamma-irradiated Anaplasma marginale organisms were studied in bovine calves. The severity of Anaplasma infection based on per cent infected red blood cells, haematological values and mortality was more in animals immunized with blood exposed to 60 kR in comparison to those inoculated with blood irradiated at 70, 80 and 90 kR. The immunizing controls demonstrated a significantly high parasitaemia, marked anaemia and more deaths. Marked and prolonged cell-mediated and humoral immune responses detectable in the first 3 weeks of post-immunization may be responsible for conferring of protective immunity. (author)

Lessons Learned from Protective Immune Responses to Optimize Vaccines against Cryptosporidiosis

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Maxime W. Lemieux

2017-12-01

Full Text Available In developing countries, cryptosporidiosis causes moderate-to-severe diarrhea and kills thousands of infants and toddlers annually. Drinking and recreational water contaminated with Cryptosporidium spp. oocysts has led to waterborne outbreaks in developed countries. A competent immune system is necessary to clear this parasitic infection. A better understanding of the immune responses required to prevent or limit infection by this protozoan parasite is the cornerstone of development of an effective vaccine. In this light, lessons learned from previously developed vaccines against Cryptosporidium spp. are at the foundation for development of better next-generation vaccines. In this review, we summarize the immune responses elicited by naturally and experimentally-induced Cryptosporidium spp. infection and by several experimental vaccines in various animal models. Our aim is to increase awareness about the immune responses that underlie protection against cryptosporidiosis and to encourage promotion of these immune responses as a key strategy for vaccine development. Innate and mucosal immunity will be addressed as well as adaptive immunity, with an emphasis on the balance between TH1/TH2 immune responses. Development of more effective vaccines against cryptosporidiosis is needed to prevent Cryptosporidium spp.-related deaths in infants and toddlers in developing countries.

The role of radiotherapy for the induction of antitumor immune responses

International Nuclear Information System (INIS)

Multhoff, G.; Helmholtz-Zentrum Muenchen; Gaipl, U.S.; Niedermann, G.

2012-01-01

Effective radiotherapy is aimed to control the growth of the primary carcinoma and to induce a long-term specific antitumor immune response against the primary tumor, recurrence and metastases. The contribution covers the following issues: T cells and tumor specific immune responses, dendritic cells (DCs) start adaptive immune responses, NK (natural killer) cells for HLA independent tumor control, abscopal effects of radiotherapy, combination of radiotherapy and immune therapy, radiotherapy contribution to the induction of immunogenic cell death, combinability of radiotherapy and DC activation, combinability of radiotherapy and NK cell therapy. It turns out that the combination of radio-chemotherapy and immune therapy can change the microenvironment initiating antitumor immune reactions that inhibit the recurrence risk and the development of metastases.

Immune responses to hair dyes containing toluene-2,5-diamine

DEFF Research Database (Denmark)

Schmidt, J D; Johansen, J D; Nielsen, M M

2014-01-01

BACKGROUND: Toluene-2,5-diamine (PTD) is the most frequently used dye in oxidative hair dyes on the Scandinavian market. However, little is known about immune responses to PTD-containing oxidative hair dyes. OBJECTIVES: To study immune responses induced by PTD-containing hair dyes in mice. METHODS......: Immune responses against two different permanent hair dye products containing 1·60% (w/w) and 0·48% (w/w) PTD within the colour gel, and various concentrations of pure PTD were studied. The local inflammatory response was measured by ear swelling and cell infiltration, and T- and B-cell infiltration...... and proliferation was determined in the draining lymph nodes. RESULTS: Concentration-dependent immune responses were seen to PTD both in the skin and draining lymph nodes. The hair dye containing 1·60% PTD induced strong local inflammation and caused T- and B-cell infiltration and proliferation as well...

Trachoma: protective and pathogenic ocular immune responses to Chlamydia trachomatis.

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Victor H Hu

Full Text Available Trachoma, caused by Chlamydia trachomatis (Ct, is the leading infectious blinding disease worldwide. Chronic conjunctival inflammation develops in childhood and leads to eyelid scarring and blindness in adulthood. The immune response to Ct provides only partial protection against re-infection, which can be frequent. Moreover, the immune response is central to the development of scarring pathology, leading to loss of vision. Here we review the current literature on both protective and pathological immune responses in trachoma. The resolution of Ct infection in animal models is IFNγ-dependent, involving Th1 cells, but whether this is the case in human ocular infection still needs to be confirmed. An increasing number of studies indicate that innate immune responses arising from the epithelium and other innate immune cells, along with changes in matrix metalloproteinase activity, are important in the development of tissue damage and scarring. Current trachoma control measures, which are centred on repeated mass antibiotic treatment of populations, are logistically challenging and have the potential to drive antimicrobial resistance. A trachoma vaccine would offer significant advantages. However, limited understanding of the mechanisms of both protective immunity and immunopathology to Ct remain barriers to vaccine development.

Bovine anaplasmosis with emphasis on immune responses and protection

International Nuclear Information System (INIS)

Ristic, M.

1980-01-01

Anaplasmosis is an infectious and transmissible disease manifested by progressive anaemia and the appearance of other characteristic disease symptoms. It is a world-wide tick-borne disease of cattle and some wild ruminants caused by the rickettsia Anaplasma marginale. By drawing on information obtained from studies of plasmodial cell cultures, a method has recently been developed for short-term in vitro cultivation of A. marginale. An attenuated Anaplasma organism capable of growth in both ovine and bovine erythrocytes was used to demonstrate that the in vitro system provided the necessary requirements for active transfer of the organism from cell to cell. Organismal antigens are found in the erythrocytes of infected animals, whereas soluble antigens are derived from their erythrocytes and serum. Serums from convalescing animals interact with these antigens in agglutination, complement fixation, fluorescent antibody and precipitation tests. Passive transfer of sera from immune to susceptible cattle, however, does not seem to confer protection against the infection and development of the disease. Studies that employed various tests for measuring cell-mediated immune (CMI) responses (leukocyte migration inhibition, blast transformation and cytotoxicity), in association with information collected simultaneously on antibody activity, have shown that both humoral and cellular immune responses are needed for the development of protective immunity in anaplasmosis. It was further shown that an active replication of Anaplasma is essential for induction of these two types of immune responses. Consequently, live virulent and attenuated immunogens fulfil requirements for induction of protective immunity. With the virulent agent, however, development of protective immunity is preceded by induction of auto-immune responses apparently associated with pathogenesis of anaemia in anaplasmosis. Inactivated immunogens derived from blood of infected cattle and used in combination with

Increased TNF-alpha/IFN-gamma/IL-2 and decreased TNF-alpha/IFN-gamma production by central memory T cells are associated with protective responses against bovine tuberculosis following BCG vaccination

Science.gov (United States)

Central memory T cells (Tcm’s) and polyfunctional CD4 T responses contribute to vaccine-elicited protection with both human and bovine tuberculosis (TB); however, their combined role in protective immunity to TB is unclear. To address this question, we evaluated polyfunctional cytokine responses by ...

The Basic Immune Simulator: An agent-based model to study the interactions between innate and adaptive immunity

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Orosz Charles G

2007-09-01

Full Text Available Abstract Background We introduce the Basic Immune Simulator (BIS, an agent-based model created to study the interactions between the cells of the innate and adaptive immune system. Innate immunity, the initial host response to a pathogen, generally precedes adaptive immunity, which generates immune memory for an antigen. The BIS simulates basic cell types, mediators and antibodies, and consists of three virtual spaces representing parenchymal tissue, secondary lymphoid tissue and the lymphatic/humoral circulation. The BIS includes a Graphical User Interface (GUI to facilitate its use as an educational and research tool. Results The BIS was used to qualitatively examine the innate and adaptive interactions of the immune response to a viral infection. Calibration was accomplished via a parameter sweep of initial agent population size, and comparison of simulation patterns to those reported in the basic science literature. The BIS demonstrated that the degree of the initial innate response was a crucial determinant for an appropriate adaptive response. Deficiency or excess in innate immunity resulted in excessive proliferation of adaptive immune cells. Deficiency in any of the immune system components increased the probability of failure to clear the simulated viral infection. Conclusion The behavior of the BIS matches both normal and pathological behavior patterns in a generic viral infection scenario. Thus, the BIS effectively translates mechanistic cellular and molecular knowledge regarding the innate and adaptive immune response and reproduces the immune system's complex behavioral patterns. The BIS can be used both as an educational tool to demonstrate the emergence of these patterns and as a research tool to systematically identify potential targets for more effective treatment strategies for diseases processes including hypersensitivity reactions (allergies, asthma, autoimmunity and cancer. We believe that the BIS can be a useful addition to

Type II membrane protein CD69 regulates the formation of resting T-helper memory.

Science.gov (United States)

Shinoda, Kenta; Tokoyoda, Koji; Hanazawa, Asami; Hayashizaki, Koji; Zehentmeier, Sandra; Hosokawa, Hiroyuki; Iwamura, Chiaki; Koseki, Haruhiko; Tumes, Damon J; Radbruch, Andreas; Nakayama, Toshinori

2012-05-08

Memory T-helper (Th) lymphocytes are crucial for the maintenance of acquired immunity to eliminate infectious pathogens. We have previously demonstrated that most memory Th lymphocytes reside and rest on stromal niches of the bone marrow (BM). Little is known, however, regarding the molecular basis for the generation and maintenance of BM memory Th lymphocytes. Here we show that CD69-deficient effector CD4 T lymphocytes fail to relocate into and persist in the BM and therefore to differentiate into memory cells. Consequently, CD69-deficient CD4 T cells fail to facilitate the production of high-affinity antibodies and the generation of BM long-lived plasma cells in the late phase of immune responses. Thus, CD69 is critical for the generation and maintenance of professional memory Th lymphocytes, which can efficiently help humoral immunity in the late phase. The deficit of immunological memory in CD69-deficient mice also highlights the essential role of BM for the establishment of Th memory.

Anopheles gambiae antiviral immune response to systemic O'nyong-nyong infection.

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Joanna Waldock

Full Text Available Mosquito-borne viral diseases cause significant burden in much of the developing world. Although host-virus interactions have been studied extensively in the vertebrate host, little is known about mosquito responses to viral infection. In contrast to mosquitoes of the Aedes and Culex genera, Anopheles gambiae, the principal vector of human malaria, naturally transmits very few arboviruses, the most important of which is O'nyong-nyong virus (ONNV. Here we have investigated the A. gambiae immune response to systemic ONNV infection using forward and reverse genetic approaches.We have used DNA microarrays to profile the transcriptional response of A. gambiae inoculated with ONNV and investigate the antiviral function of candidate genes through RNAi gene silencing assays. Our results demonstrate that A. gambiae responses to systemic viral infection involve genes covering all aspects of innate immunity including pathogen recognition, modulation of immune signalling, complement-mediated lysis/opsonisation and other immune effector mechanisms. Patterns of transcriptional regulation and co-infections of A. gambiae with ONNV and the rodent malaria parasite Plasmodium berghei suggest that hemolymph immune responses to viral infection are diverted away from melanisation. We show that four viral responsive genes encoding two putative recognition receptors, a galectin and an MD2-like receptor, and two effector lysozymes, function in limiting viral load.This study is the first step in elucidating the antiviral mechanisms of A. gambiae mosquitoes, and has revealed interesting differences between A. gambiae and other invertebrates. Our data suggest that mechanisms employed by A. gambiae are distinct from described invertebrate antiviral immunity to date, and involve the complement-like branch of the humoral immune response, supressing the melanisation response that is prominent in anti-parasitic immunity. The antiviral immune response in A. gambiae is thus

Pulmonary Immune-Compartment-Specific Interferon Gamma Responses in HIV-Infected Individuals with Active Tuberculosis (TB in an Area of High TB Prevalence

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S. Buldeo

2012-01-01

Full Text Available There is a paucity of data on the pulmonary immune-compartment interferon gamma (IFNγ response to M. tuberculosis, particularly in settings of high tuberculosis (TB prevalence and in HIV-coinfected individuals. This data is necessary to understand the diagnostic potential of commercially available interferon gamma release assays (IGRAs in both the pulmonary immune-compartment and peripheral blood. We used intracellular cytokine staining by flow cytometry to assess the IFNγ response to purified protein derivative (PPD and early secretory antigen 6 (ESAT6 in induced sputa (ISp and blood samples from HIV-infected, smear-negative, TB suspects. We found that individuals with active TB disease produced significantly less IFNγ in response to PPD in their induced sputa samples than individuals with non-active TB (control group. This difference was not reflected in the peripheral blood, even within the CD27− CD4+ memory T lymphocyte population. These findings suggest that progression to active TB disease may be associated with the loss of IFNγ secretion at the site of primary infection. Our findings highlight the importance of studying pulmonary immune-compartment M. tuberculosis specific responses to elucidate IFNγ secretion across the spectrum of TB disease.

Mechanisms Underlying the Immune Response Generated by an Oral Vibrio cholerae Vaccine

Directory of Open Access Journals (Sweden)

Danylo Sirskyj

2016-07-01

Full Text Available Mechanistic details underlying the resulting protective immune response generated by mucosal vaccines remain largely unknown. We investigated the involvement of Toll-like receptor signaling in the induction of humoral immune responses following oral immunization with Dukoral, comparing wild type mice with TLR-2-, TLR-4-, MyD88- and Trif-deficient mice. Although all groups generated similar levels of IgG antibodies, the proliferation of CD4+ T-cells in response to V. cholerae was shown to be mediated via MyD88/TLR signaling, and independently of Trif signaling. The results demonstrate differential requirements for generation of immune responses. These results also suggest that TLR pathways may be modulators of the quality of immune response elicited by the Dukoral vaccine. Determining the critical signaling pathways involved in the induction of immune response to this vaccine would be beneficial, and could contribute to more precisely-designed versions of other oral vaccines in the future.

Anterior Chamber-Associated Immune Deviation (ACAID: An Acute Response to Ocular Insult Protects from Future Immune-Mediated Damage?

Directory of Open Access Journals (Sweden)

Robert E. Cone

2009-01-01

Full Text Available The “immune privilege” that inhibits immune defense mechanisms that could lead to damage to sensitive ocular tissue is based on the expression of immunosuppressive factors on ocular tissue and in ocular fluids. In addition to this environmental protection, the injection of antigen into the anterior chamber or infection in the anterior chamber induces a systemic suppression of potentially damaging cell-mediated and humoral responses to the antigen. Here we discuss evidence that suggests that Anterior Chamber-Associated Immune Deviation (ACAID a is initiated by an ocular response to moderate inflammation that leads to a systemic immunoregulatory response. Injection into the anterior chamber induces a rise in TNF-α and MCP-1 in aqueous humor and an infiltration of circulating F4/80 + monocytes that home to the iris. The induction of ACAID is dependent on this infiltration of circulating monocytes that eventually emigrate to the thymus and spleen where they induce regulatory T cells that inhibit the inductive or effector phases of a cell-mediated immune response. ACAID therefore protects the eye from the collateral damage of an immune response to infection by suppressing a future potentially damaging response to infection.

Pretreatment antigen-specific immunity and regulation - association with subsequent immune response to anti-tumor DNA vaccination.

Science.gov (United States)

Johnson, Laura E; Olson, Brian M; McNeel, Douglas G

2017-07-18

Immunotherapies have demonstrated clinical benefit for many types of cancers, however many patients do not respond, and treatment-related adverse effects can be severe. Hence many efforts are underway to identify treatment predictive biomarkers. We have reported the results of two phase I trials using a DNA vaccine encoding prostatic acid phosphatase (PAP) in patients with biochemically recurrent prostate cancer. In both trials, persistent PAP-specific Th1 immunity developed in some patients, and this was associated with favorable changes in serum PSA kinetics. In the current study, we sought to determine if measures of antigen-specific or antigen non-specific immunity were present prior to treatment, and associated with subsequent immune response, to identify possible predictive immune biomarkers. Patients who developed persistent PAP-specific, IFNγ-secreting immune responses were defined as immune "responders." The frequency of peripheral T cell and B cell lymphocytes, natural killer cells, monocytes, dendritic cells, myeloid derived suppressor cells, and regulatory T cells were assessed by flow cytometry and clinical laboratory values. PAP-specific immune responses were evaluated by cytokine secretion in vitro, and by antigen-specific suppression of delayed-type hypersensitivity to a recall antigen in an in vivo SCID mouse model. The frequency of peripheral blood cell types did not differ between the immune responder and non-responder groups. Non-responder patients tended to have higher PAP-specific IL-10 production pre-vaccination (p = 0.09). Responder patients had greater preexisting PAP-specific bystander regulatory responses that suppressed DTH to a recall antigen (p = 0.016). While our study population was small (n = 38), these results suggest that different measures of antigen-specific tolerance or regulation might help predict immunological outcome from DNA vaccination. These will be prospectively evaluated in an ongoing randomized, phase II trial.

Reprogramming Antitumor Immune Responses with microRNAs

Science.gov (United States)

2013-10-01

disease, including cancer etiology (4) and the generation and inhibition of antitumor immune responses (5–9). Biologically active miRNAs bind to MREs...breast, colorectal, lung, pancreatic , and thyroid carcinomas and in liquid tumors including lymphomas and some acute myeloid leukemias (9, 35). The...immunity [9], underscoring the potential of targeting this major microenvironmental compartment. Accumulating evidence suggests that chronic

Heavy metal pollution disturbs immune response in wild ant populations

International Nuclear Information System (INIS)

Sorvari, Jouni; Rantala, Liisa M.; Rantala, Markus J.; Hakkarainen, Harri; Eeva, Tapio

2007-01-01

Concern about the effects of environmental contaminants on immune function in both humans and wildlife is growing and practically nothing is known about this impact on terrestrial invertebrates, even though they are known to easily accumulate pollutants. We studied the effect of industrial heavy metal contamination on immune defense of a free-living wood ant (Formica aquilonia). To find out whether ants show an adapted immune function in a polluted environment, we compared encapsulation responses between local and translocated colonies. Local colonies showed higher heavy metal levels than the translocated ones but the encapsulation response was similar between the two groups, indicating that the immune system of local ants has not adapted to high contamination level. The encapsulation response was elevated in moderate whereas suppressed in high heavy metal levels suggesting higher risk for infections in heavily polluted areas. - Heavy metal pollution affects immune function in ants

Immune Boosting Explains Regime-Shifts in Prevaccine-Era Pertussis Dynamics

DEFF Research Database (Denmark)

Lavine, Jennie; King, Aaron A; Andreasen, Viggo

2013-01-01

Understanding the biological mechanisms underlying episodic outbreaks of infectious diseases is one of mathematical epidemiology’s major goals. Historic records are an invaluable source of information in this enterprise. Pertussis (whooping cough) is a re-emerging infection whose intermittent bouts...... with permanent or passively-waning immunity. Our results emphasize the importance of understanding the mechanisms responsible for maintaining immune memory for pertussis epidemiology....

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

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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.

Co-administration of α-GalCer analog and TLR4 agonist induces robust CD8(+) T-cell responses to PyCS protein and WT-1 antigen and activates memory-like effector NKT cells.

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Coelho-Dos-Reis, Jordana G; Huang, Jing; Tsao, Tiffany; Pereira, Felipe V; Funakoshi, Ryota; Nakajima, Hiroko; Sugiyama, Haruo; Tsuji, Moriya

2016-07-01

In the present study, the combined adjuvant effect of 7DW8-5, a potent α-GalCer-analog, and monophosphoryl lipid A (MPLA), a TLR4 agonist, on the induction of vaccine-induced CD8(+) T-cell responses and protective immunity was evaluated. Mice were immunized with peptides corresponding to the CD8(+) T-cell epitopes of a malaria antigen, a circumsporozoite protein of Plasmodium yoelii, and a tumor antigen, a Wilms Tumor antigen-1 (WT-1), together with 7DW8-5 and MPLA, as an adjuvant. These immunization regimens were able to induce higher levels of CD8(+) T-cell responses and, ultimately, enhanced levels of protection against malaria and tumor challenges compared to the levels induced by immunization with peptides mixed with 7DW8-5 or MPLA alone. Co-administration of 7DW8-5 and MPLA induces activation of memory-like effector natural killer T (NKT) cells, i.e. CD44(+)CD62L(-)NKT cells. Our study indicates that 7DW8-5 greatly enhances important synergistic pathways associated to memory immune responses when co-administered with MPLA, thus rendering this combination of adjuvants a novel vaccine adjuvant formulation. Copyright © 2016 Elsevier Inc. All rights reserved.

Bystander chronic infection negatively impacts development of CD8+ T cell memory

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Stelekati, Erietta; Shin, Haina; Doering, Travis A.; Dolfi, Douglas V.; Ziegler, Carly G.; Beiting, Daniel P.; Dawson, Lucas; Liboon, Jennifer; Wolski, David; Ali, Mohammed-Alkhatim A.; Katsikis, Peter D.; Shen, Hao; Roos, David S.; Haining, W. Nicholas; Lauer, Georg M.; Wherry, E. John

2014-01-01

Summary Epidemiological evidence suggests that chronic infections impair immune responses to unrelated pathogens and vaccines. The underlying mechanisms, however, are unclear and distinguishing effects on priming versus development of immunological memory has been challenging. We investigated whether bystander chronic infections impact differentiation of memory CD8+ T cells, the hallmark of protective immunity against intracellular pathogens. Chronic bystander infections impaired development of memory CD8+ T cells in several mouse models and humans. These effects were independent of initial priming and were associated with chronic inflammatory signatures. Chronic inflammation negatively impacted the number of bystander CD8+ T cells and their memory development. Distinct underlying mechanisms of altered survival and differentiation were revealed with the latter regulated by the transcription factors T-bet and Blimp-1. Thus, exposure to prolonged bystander inflammation impairs the effector to memory transition. These data have relevance for immunity and vaccination during persisting infections and chronic inflammation. PMID:24837104

Immune Response to Dengue and Zika.

Science.gov (United States)

Ngono, Annie Elong; Shresta, Sujan

2018-04-26

Flaviviruses such as dengue (DENV), yellow fever (YFV), West Nile (WNV), and Zika (ZIKV) are human pathogens of global significance. In particular, DENV causes the most prevalent mosquito-borne viral diseases in humans, and ZIKV emerged from obscurity into the spotlight in 2016 as the etiologic agent of congenital Zika syndrome. Owing to the recent emergence of ZIKV as a global pandemic threat, the roles of the immune system during ZIKV infections are as yet unclear. In contrast, decades of DENV research implicate a dual role for the immune system in protection against and pathogenesis of DENV infection. As DENV and ZIKV are closely related, knowledge based on DENV studies has been used to prioritize investigation of ZIKV immunity and pathogenesis, and to accelerate ZIKV diagnostic, therapeutic, and vaccine design. This review discusses the following topics related to innate and adaptive immune responses to DENV and ZIKV: the interferon system as the key mechanism of host defense and viral target for immune evasion, antibody-mediated protection versus antibody-dependent enhancement, and T cell-mediated protection versus original T cell antigenic sin. Understanding the mechanisms that regulate the balance between immune-mediated protection and pathogenesis during DENV and ZIKV infections is critical toward development of safe and effective DENV and ZIKV therapeutics and vaccines.

Skin immunization by microneedle patch overcomes statin-induced suppression of immune responses to influenza vaccine.

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Vassilieva, Elena V; Wang, Shelly; Li, Song; Prausnitz, Mark R; Compans, Richard W

2017-12-19

Recent studies indicated that in elderly individuals, statin therapy is associated with a reduced response to influenza vaccination. The present study was designed to determine effects on the immune response to influenza vaccination induced by statin administration in a mouse model, and investigate potential approaches to improve the outcome of vaccination on the background of statin therapy. We fed middle aged BALB/c mice a high fat "western" diet (WD) alone or supplemented with atorvastatin (AT) for 14 weeks, and control mice were fed with the regular rodent diet. Mice were immunized with a single dose of subunit A/Brisbane/59/07 (H1N1) vaccine, either systemically or with dissolving microneedle patches (MNPs). We observed that a greater age-dependent decline in the hemagglutinin inhibition titers occurred in systemically-immunized mice than in MNP- immunized mice. AT dampened the antibody response in the animals vaccinated by either route of vaccine delivery. However, the MNP-vaccinated AT-treated animals had ~20 times higher total antibody levels to the influenza vaccine than the systemically vaccinated group one month postvaccination. We propose that microneedle vaccination against influenza provides an approach to ameliorate the immunosuppressive effect of statin therapy observed with systemic immunization.

Effective Respiratory CD8 T-Cell Immunity to Influenza Virus Induced by Intranasal Carbomer-Lecithin-Adjuvanted Non-replicating Vaccines

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Gasper, David J.; Neldner, Brandon; Plisch, Erin H.; Rustom, Hani; Imai, Hirotaka; Kawaoka, Yoshihiro; Suresh, M.

2016-01-01

CD8+ cytotoxic T lymphocytes (CTLs) are critical for clearing many viral infections, and protective CTL memory can be induced by vaccination with attenuated viruses and vectors. Non-replicating vaccines are typically potentiated by the addition of adjuvants that enhance humoral responses, however few are capable of generating CTL responses. Adjuplex is a carbomer-lecithin-based adjuvant demonstrated to elicit robust humoral immunity to non-replicating antigens. We report that mice immunized with non-replicating Adjuplex-adjuvanted vaccines generated robust antigen-specific CTL responses. Vaccination by the subcutaneous or the intranasal route stimulated systemic and mucosal CTL memory respectively. However, only CTL memory induced by intranasal vaccination was protective against influenza viral challenge, and correlated with an enhancement of memory CTLs in the airways and CD103+ CD69+ CXCR3+ resident memory-like CTLs in the lungs. Mechanistically, Myd88-deficient mice mounted primary CTL responses to Adjuplex vaccines that were similar in magnitude to wild-type mice, but exhibited altered differentiation of effector cell subsets. Immune potentiating effects of Adjuplex entailed alterations in the frequency of antigen-presenting-cell subsets in vaccine draining lymph nodes, and in the lungs and airways following intranasal vaccination. Further, Adjuplex enhanced the ability of dendritic cells to promote antigen-induced proliferation of naïve CD8 T cells by modulating antigen uptake, its intracellular localization, and rate of processing. Taken together, we have identified an adjuvant that elicits both systemic and mucosal CTL memory to non-replicating antigens, and engenders protective CTL-based heterosubtypic immunity to influenza A virus in the respiratory tract. Further, findings presented in this manuscript have provided key insights into the mechanisms and factors that govern the induction and programming of systemic and protective memory CTLs in the

Eosinophils in mucosal immune responses

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Travers, J; Rothenberg, M E

2015-01-01

Eosinophils, multifunctional cells that contribute to both innate and adaptive immunity, are involved in the initiation, propagation and resolution of immune responses, including tissue repair. They achieve this multifunctionality by expression of a diverse set of activation receptors, including those that directly recognize pathogens and opsonized targets, and by their ability to store and release preformed cytotoxic mediators that participate in host defense, to produce a variety of de novo pleotropic mediators and cytokines and to interact directly and indirectly with diverse cell types, including adaptive and innate immunocytes and structural cells. Herein, we review the basic biology of eosinophils and then focus on new emerging concepts about their role in mucosal immune homeostasis, particularly maintenance of intestinal IgA. We review emerging data about their development and regulation and describe new concepts concerning mucosal eosinophilic diseases. We describe recently developed therapeutic strategies to modify eosinophil levels and function and provide collective insight about the beneficial and detrimental functions of these enigmatic cells. PMID:25807184

Functional characterization of Foxp3-specific spontaneous immune responses

DEFF Research Database (Denmark)

Larsen, Susanne Købke; Munir, S; Andersen, Anders Woetmann

2013-01-01

Tumor-infiltrating CD4+CD25+ regulatory T cells (Tregs) are associated with an impaired prognosis in several cancers. The transcription factor forkhead box P3 (Foxp3) is generally expressed in Tregs. Here, we identify and characterize spontaneous cytotoxic immune responses to Foxp3-expressing cel....... Consequently, induction of Foxp3-specific cytotoxic T-cell responses appears as an attractive tool to boost spontaneous or therapeutically provoked immune responses, for example, for the therapy of cancer....

Skin effector memory T cells do not recirculate and provide immune protection in alemtuzumab-treated CTCL patients.

Science.gov (United States)

Clark, Rachael A; Watanabe, Rei; Teague, Jessica E; Schlapbach, Christoph; Tawa, Marianne C; Adams, Natalie; Dorosario, Andrew A; Chaney, Keri S; Cutler, Corey S; Leboeuf, Nicole R; Carter, Joi B; Fisher, David C; Kupper, Thomas S

2012-01-18

Cutaneous T cell lymphoma (CTCL) is a cancer of skin-homing T cells with variants that include leukemic CTCL (L-CTCL), a malignancy of central memory T cells (T(CM)), and mycosis fungoides (MF), a malignancy of skin resident effector memory T cells (T(EM)). We report that low-dose alemtuzumab (αCD52) effectively treated patients with refractory L-CTCL but not MF. Alemtuzumab depleted all T cells in blood and depleted both benign and malignant T(CM) from skin, but a diverse population of skin resident T(EM) remained in skin after therapy. T cell depletion with alemtuzumab required the presence of neutrophils, a cell type frequent in blood but rare in normal skin. These data suggest that T(CM) were depleted because they recirculate between the blood and the skin, whereas skin resident T(EM) were spared because they are sessile and non-recirculating. After alemtuzumab treatment, skin T cells produced lower amounts of interleukin-4 and higher amounts of interferon-γ. Moreover, there was a marked lack of infections in alemtuzumab-treated L-CTCL patients despite the complete absence of T cells in the blood, suggesting that skin resident T(EM) can protect the skin from pathogens even in the absence of T cell recruitment from the circulation. Together, these data suggest that alemtuzumab may treat refractory L-CTCL without severely compromising the immune response to infection by depleting circulating T(CM) but sparing the skin resident T(EM) that provide local immune protection of the skin.

A multiherbal formulation influencing immune response in vitro.

Science.gov (United States)

Menghini, L; Leporini, L; Scanu, N; Pintore, G; Ferrante, C; Recinella, L; Orlando, G; Vacca, M; Brunetti, L

2012-02-01

Aim of this study was to evaluate the effects of phytocomplexes of Uncaria, Shiitake and Ribes in terms of viability and inflammatory response on immune cell-derived cultures. Standardized extracts of Uncaria, Shitake and Ribes and their commercial formulation were tested on cell lines PBMC, U937 and macrophage. The activity was evaluated in terms of cell viability (MTT test), variations of oxidative marker release (ROS and PGE2) and modulatory effects on immune response (gene expression of IL-6, IL-8 and TNFα, RT-PCR). Cell viability was not affected by extracts, except subtle variations observed only at higher doses (>250 µg/mL). The extract mixture was well tolerated, with no effects on cell viability up to doses of 500 µg/mL. Pre-treatment of macrophages with subtoxic doses of the extracts reduced the basal release of oxidative markers and enhanced the cell response to exogenous oxidant stimulation, as revealed by ROS and PGE2 release reduction. The same treatment on macrophage resulted in a selective modulation of the immune response, as shown by an increase of IL-6 mRNA and, partially, IL-8 mRNA, while a reduction was observed for TNFα mRNA. Data confirm that extracts and their formulations can act as regulator of the immune system with mechanisms involving the oxidative stress and the release of selected proinflammatory cytokines.

DNA Damage Response and Immune Defence: Links and Mechanisms

Directory of Open Access Journals (Sweden)

Björn Schumacher

2016-08-01

Full Text Available DNA damage plays a causal role in numerous human pathologies including cancer, premature aging and chronic inflammatory conditions. In response to genotoxic insults, the DNA damage response (DDR orchestrates DNA damage checkpoint activation and facilitates the removal of DNA lesions. The DDR can also arouse the immune system by for example inducing the expression of antimicrobial peptides as well as ligands for receptors found on immune cells. The activation of immune signalling is triggered by different components of the DDR including DNA damage sensors, transducer kinases, and effectors. In this review, we describe recent advances on the understanding of the role of DDR in activating immune signalling. We highlight evidence gained into (i which molecular and cellular pathways of DDR activate immune signalling, (ii how DNA damage drives chronic inflammation, and (iii how chronic inflammation causes DNA damage and pathology in humans.

Pathogen recognition in the innate immune response.

Science.gov (United States)

Kumar, Himanshu; Kawai, Taro; Akira, Shizuo

2009-04-28

Immunity against microbial pathogens primarily depends on the recognition of pathogen components by innate receptors expressed on immune and non-immune cells. Innate receptors are evolutionarily conserved germ-line-encoded proteins and include TLRs (Toll-like receptors), RLRs [RIG-I (retinoic acid-inducible gene-I)-like receptors] and NLRs (Nod-like receptors). These receptors recognize pathogens or pathogen-derived products in different cellular compartments, such as the plasma membrane, the endosomes or the cytoplasm, and induce the expression of cytokines, chemokines and co-stimulatory molecules to eliminate pathogens and instruct pathogen-specific adaptive immune responses. In the present review, we will discuss the recent progress in the study of pathogen recognition by TLRs, RLRs and NLRs and their signalling pathways.

Oncolytic Viral Therapy and the Immune System: A Double-Edged Sword Against Cancer.

Science.gov (United States)

Marelli, Giulia; Howells, Anwen; Lemoine, Nicholas R; Wang, Yaohe

2018-01-01

Oncolytic viral therapy is a new promising strategy against cancer. Oncolytic viruses (OVs) can replicate in cancer cells but not in normal cells, leading to lysis of the tumor mass. Beside this primary effect, OVs can also stimulate the immune system. Tumors are an immuno-suppressive environment in which the immune system is silenced in order to avoid the immune response against cancer cells. The delivery of OVs into the tumor wakes up the immune system so that it can facilitate a strong and durable response against the tumor itself. Both innate and adaptive immune responses contribute to this process, producing an immune response against tumor antigens and facilitating immunological memory. However, viruses are recognized by the immune system as pathogens and the consequent anti-viral response could represent a big hurdle for OVs. Finding a balance between anti-tumor and anti-viral immunity is, under this new light, a priority for researchers. In this review, we provide an overview of the various ways in which different components of the immune system can be allied with OVs. We have analyzed the different immune responses in order to highlight the new and promising perspectives leading to increased anti-tumor response and decreased immune reaction to the OVs.

Modulation of the immune response by emotional stress

NARCIS (Netherlands)

Croiset, G; Heijnen, C J; Veldhuis, H D; de Wied, D; Ballieux, R E

1987-01-01

The influence of mild, emotional stress was investigated for its effect on the immune system by subjecting rats to the one-trial-learning passive avoidance test. The reactivity of the immune system was tested by determining the proliferative response after mitogenic stimulation in vitro as well as

The sterile immune response during hepatic ischemia/reperfusion

NARCIS (Netherlands)

van Golen, Rowan F.; van Gulik, Thomas M.; Heger, Michal

2012-01-01

Hepatic ischemia and reperfusion elicits an immune response that lacks a microbial constituent yet poses a potentially lethal threat to the host. In this sterile setting, the immune system is alarmed by endogenous danger signals that are release by stressed and dying liver cells. The detection of

Inflammatory cytokines in the brain: does the CNS shape immune responses?

Science.gov (United States)

Owens, T; Renno, T; Taupin, V; Krakowski, M

1994-12-01

Immune responses in the central nervous system (CNS) have traditionally been regarded as representing the intrusion of an unruly, ill-behaved mob of leukocytes into the well-ordered and organized domain of thought and reason. However, results accumulated over the past few years suggest that, far from being an immunologically privileged organ, T lymphocytes may be regular and frequent visitors to the CNS, for purposes of immune surveillance. Here, Trevor Owens and colleagues propose that the brain itself can regulate or shape immune responses therein. Furthermore, given that the immune cells may be subverted to autoimmunity, they suggest that the study of inflammatory autoimmune disease in the brain may shed light on the ability of the local environment to regulate immune responses.

Influence of bedding type on mucosal immune responses.

Science.gov (United States)

Sanford, Amy N; Clark, Stephanie E; Talham, Gwen; Sidelsky, Michael G; Coffin, Susan E

2002-10-01

The mucosal immune system interacts with the external environment. In the study reported here, we found that bedding materials can influence the intestinal immune responses of mice. We observed that mice housed on wood, compared with cotton bedding, had increased numbers of Peyer's patches (PP) visible under a dissecting microscope. In addition, culture of lymphoid organs revealed increased production of total and virus-specific IgA by PP and mesenteric lymph node (MLN) lymphocytes from mice housed on wood, compared with cotton bedding. However, bedding type did not influence serum virus-specific antibody responses. These observations indicate that bedding type influences the intestinal immune system and suggest that this issue should be considered by mucosal immunologists and personnel at animal care facilities.

Adrenaline influence on the immune response. I

International Nuclear Information System (INIS)

Depelchin, A.; Letesson, J.J.

1981-01-01

The intervention of adrenaline in the immunoregulation was investigated through the modification of the anti-SRBC PFC response of mice after its i.p. administration (4 μg) at various intervals before SRBC antigen. When the interval was less than 24 h, adrenaline accelerated the immune kinetics. This modification was apparent on both direct and indirect PFC, as well as on naive and immune mice. However, mice treated from 2 days showed a suppression of the response. The adrenaline affect subsisted on the adoptive response of spleen cells drug-treated either in vivo or in vitro. The mitogenic response after in vitro PHA or LPS stimulation of spleen cells from adrenaline-treated mice indicated that the T-cells were the drug target. The physiological role of the adrenaline and immunological influences of acute stress are discussed in the paper. The stress was provided by gamma irradiation. (Auth.)

Detection of herpes simplex virus type 2 (HSV-2) -specific cell-mediated immune responses in guinea pigs during latent HSV-2 genital infection.

Science.gov (United States)

Perry, Clarice L; Banasik, Brianne N; Gorder, Summer R; Xia, Jingya; Auclair, Sarah; Bourne, Nigel; Milligan, Gregg N

2016-12-01

Genital infections with herpes simplex virus type 2 (HSV-2) are a source of considerable morbidity and are a health concern for newborns exposed to virus during vaginal delivery. Additionally, HSV-2 infection diminishes the integrity of the vaginal epithelium resulting in increased susceptibility of individuals to infection with other sexually transmitted pathogens. Understanding immune protection against HSV-2 primary infection and immune modulation of virus shedding events following reactivation of the virus from latency is important for the development of effective prophylactic and therapeutic vaccines. Although the murine model of HSV-2 infection is useful for understanding immunity following immunization, it is limited by the lack of spontaneous reactivation of HSV-2 from latency. Genital infection of guinea pigs with HSV-2 accurately models the disease of humans including the spontaneous reactivation of HSV-2 from latency and provides a unique opportunity to examine virus-host interactions during latency. Although the guinea pig represents an accurate model of many human infections, relatively few reagents are available to study the immunological response to infection. To analyze the cell-mediated immune response of guinea pigs at extended periods of time after establishment of HSV-2 latency, we have modified flow-cytometry based proliferation assays and IFN-γ ELISPOT assays to detect and quantify HSV-specific cell-mediated responses during latent infection of guinea pigs. Here we demonstrate that a combination of proliferation and ELISPOT assays can be used to quantify and characterize effecter function of virus-specific immune memory responses during HSV-latency. Copyright © 2016 Elsevier B.V. All rights reserved.

Respons imun humoral pada pulpitis (Humoral immune response on pulpitis)

OpenAIRE

Widodo, Trijoedani

2005-01-01

Pulpitis is an inflammation process on dental pulp tissue, and usually as the continuous of caries. The microorganism in the caries is a potential immunogenic triggering the immune respons, both humoral and celluler immune responses. The aim of this research is to explain the humoral immune response changes in the dental pulp tissues of pulpitis. This research was done on three group samples: Irreversible pulpitis, Reversible pulpitis and sound teeth as the control group. The result showed th...

The host immune response to Clostridium difficile infection

Science.gov (United States)

2013-01-01

Clostridium difficile infection (CDI) is the most common infectious cause of healthcare-acquired diarrhoea. Outcomes of C. difficile colonization are varied, from asymptomatic carriage to fulminant colitis and death, due in part to the interplay between the pathogenic virulence factors of the bacterium and the counteractive immune responses of the host. Secreted toxins A and B are the major virulence factors of C. difficile and induce a profound inflammatory response by intoxicating intestinal epithelial cells causing proinflammatory cytokine release. Host cell necrosis, vascular permeability and neutrophil infiltration lead to an elevated white cell count, profuse diarrhoea and in severe cases, dehydration, hypoalbuminaemia and toxic megacolon. Other bacterial virulence factors, including surface layer proteins and flagella proteins, are detected by host cell surface signal molecules that trigger downstream cell-mediated immune pathways. Human studies have identified a role for serum and faecal immunoglobulin levels in protection from disease, but the recent development of a mouse model of CDI has enabled studies into the precise molecular interactions that trigger the immune response during infection. Key effector molecules have been identified that can drive towards a protective anti-inflammatory response or a damaging proinflammatory response. The limitations of current antimicrobial therapies for CDI have led to the development of both active and passive immunotherapies, none of which have, as yet been formally approved for CDI. However, recent advances in our understanding of the molecular basis of host immune protection against CDI may provide an exciting opportunity for novel therapeutic developments in the future. PMID:25165542

Role of MicroRNAs in Obesity-Induced Metabolic Disorder and Immune Response.

Science.gov (United States)

Zhong, Hong; Ma, Minjuan; Liang, Tingming; Guo, Li

2018-01-01

In all living organisms, metabolic homeostasis and the immune system are the most fundamental requirements for survival. Recently, obesity has become a global public health issue, which is the cardinal risk factor for metabolic disorder. Many diseases emanating from obesity-induced metabolic dysfunction are responsible for the activated immune system, including innate and adaptive responses. Of note, inflammation is the manifest accountant signal. Deeply studied microRNAs (miRNAs) have participated in many pathways involved in metabolism and immune responses to protect cells from multiple harmful stimulants, and they play an important role in determining the progress through targeting different inflammatory pathways. Thus, immune response and metabolic regulation are highly integrated with miRNAs. Collectively, miRNAs are the new targets for therapy in immune dysfunction.

Characterization of functional antibody and memory B-cell responses to pH1N1 monovalent vaccine in HIV-infected children and youth.

Directory of Open Access Journals (Sweden)

Donna J Curtis

Full Text Available We investigated immune determinants of antibody responses and B-cell memory to pH1N1 vaccine in HIV-infected children.Ninety subjects 4 to <25 years of age received two double doses of pH1N1 vaccine. Serum and cells were frozen at baseline, after each vaccination, and at 28 weeks post-immunization. Hemagglutination inhibition (HAI titers, avidity indices (AI, B-cell subsets, and pH1N1 IgG and IgA antigen secreting cells (ASC were measured at baseline and after each vaccination. Neutralizing antibodies and pH1N1-specific Th1, Th2 and Tfh cytokines were measured at baseline and post-dose 1.At entry, 26 (29% subjects had pH1N1 protective HAI titers (≥1:40. pH1N1-specific HAI, neutralizing titers, AI, IgG ASC, IL-2 and IL-4 increased in response to vaccination (p<0.05, but IgA ASC, IL-5, IL-13, IL-21, IFNγ and B-cell subsets did not change. Subjects with baseline HAI ≥1:40 had significantly greater increases in IgG ASC and AI after immunization compared with those with HAI <1:40. Neutralizing titers and AI after vaccination increased with older age. High pH1N1 HAI responses were associated with increased IgG ASC, IFNγ, IL-2, microneutralizion titers, and AI. Microneutralization titers after vaccination increased with high IgG ASC and IL-2 responses. IgG ASC also increased with high IFNγ responses. CD4% and viral load did not predict the immune responses post-vaccination, but the B-cell distribution did. Notably, vaccine immunogenicity increased with high CD19+CD21+CD27+% resting memory, high CD19+CD10+CD27+% immature activated, low CD19+CD21-CD27-CD20-% tissue-like, low CD19+CD21-CD27-CD20-% transitional and low CD19+CD38+HLADR+% activated B-cell subsets.HIV-infected children on HAART mount a broad B-cell memory response to pH1N1 vaccine, which was higher for subjects with baseline HAI≥1:40 and increased with age, presumably due to prior exposure to pH1N1 or to other influenza vaccination/infection. The response to the vaccine was dependent

Allergic TH2 Response Governed by B-Cell Lymphoma 6 Function in Naturally Occurring Memory Phenotype CD4+ T Cells.

Science.gov (United States)

Ogasawara, Takashi; Kohashi, Yuko; Ikari, Jun; Taniguchi, Toshibumi; Tsuruoka, Nobuhide; Watanabe-Takano, Haruko; Fujimura, Lisa; Sakamoto, Akemi; Hatano, Masahiko; Hirata, Hirokuni; Fukushima, Yasutsugu; Fukuda, Takeshi; Kurasawa, Kazuhiro; Tatsumi, Koichiro; Tokuhisa, Takeshi; Arima, Masafumi

2018-01-01

Transcriptional repressor B-cell lymphoma 6 (Bcl6) appears to regulate T H 2 immune responses in allergies, but its precise role is unclear. We previously reported that Bcl6 suppressed IL-4 production in naïve CD4 + T cell-derived memory T H 2 cells. To investigate Bcl6 function in allergic responses in naturally occurring memory phenotype CD4 + T (MPT) cells and their derived T H 2 (MPT H 2) cells, Bcl6 -manipulated mice , highly conserved intron enhancer (hcIE)-deficient mice , and reporter mice for conserved noncoding sequence 2 (CNS2) 3' distal enhancer region were used to elucidate Bcl6 function in MPT cells. The molecular mechanisms of Bcl6-mediated T H 2 cytokine gene regulation were elucidated using cellular and molecular approaches. Bcl6 function in MPT cells was determined using adoptive transfer to naïve mice, which were assessed for allergic airway inflammation. Bcl6 suppressed IL-4 production in MPT and MPT H 2 cells by suppressing CNS2 enhancer activity. Bcl6 downregulated Il4 expression in MPT H 2 cells, but not MPT cells, by suppressing hcIE activity. The inhibitory functions of Bcl6 in MPT and MPT H 2 cells attenuated allergic responses. Bcl6 is a critical regulator of IL-4 production by MPT and MPT H 2 cells in T H 2 immune responses related to the pathogenesis of allergies.

Allergic TH2 Response Governed by B-Cell Lymphoma 6 Function in Naturally Occurring Memory Phenotype CD4+ T Cells

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Ogasawara, Takashi; Kohashi, Yuko; Ikari, Jun; Taniguchi, Toshibumi; Tsuruoka, Nobuhide; Watanabe-Takano, Haruko; Fujimura, Lisa; Sakamoto, Akemi; Hatano, Masahiko; Hirata, Hirokuni; Fukushima, Yasutsugu; Fukuda, Takeshi; Kurasawa, Kazuhiro; Tatsumi, Koichiro; Tokuhisa, Takeshi; Arima, Masafumi

2018-01-01

Transcriptional repressor B-cell lymphoma 6 (Bcl6) appears to regulate TH2 immune responses in allergies, but its precise role is unclear. We previously reported that Bcl6 suppressed IL-4 production in naïve CD4+ T cell-derived memory TH2 cells. To investigate Bcl6 function in allergic responses in naturally occurring memory phenotype CD4+ T (MPT) cells and their derived TH2 (MPTH2) cells, Bcl6-manipulated mice, highly conserved intron enhancer (hcIE)-deficient mice, and reporter mice for conserved noncoding sequence 2 (CNS2) 3′ distal enhancer region were used to elucidate Bcl6 function in MPT cells. The molecular mechanisms of Bcl6-mediated TH2 cytokine gene regulation were elucidated using cellular and molecular approaches. Bcl6 function in MPT cells was determined using adoptive transfer to naïve mice, which were assessed for allergic airway inflammation. Bcl6 suppressed IL-4 production in MPT and MPTH2 cells by suppressing CNS2 enhancer activity. Bcl6 downregulated Il4 expression in MPTH2 cells, but not MPT cells, by suppressing hcIE activity. The inhibitory functions of Bcl6 in MPT and MPTH2 cells attenuated allergic responses. Bcl6 is a critical regulator of IL-4 production by MPT and MPTH2 cells in TH2 immune responses related to the pathogenesis of allergies. PMID:29696026

Tumor PDT-associated immune response: relevance of sphingolipids

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Korbelik, Mladen; Merchant, Soroush; Separovic, Duska M.

2010-02-01

Sphingolipids have become recognized as essential effector molecules in signal transduction with involvement in various aspects of cell function and death, immune response and cancer treatment response. Major representatives of sphingolipids family, ceramide, sphingosine and sphingosine-1-phosphate (S1P), have attracted interest in their relevance to tumor response to photodynamic therapy (PDT) because of their roles as enhancers of apoptosis, mediators of cell growth and vasculogenesis, and regulators of immune response. Our recent in vivo studies with mouse tumor models have confirmed that PDT treatment has a pronounced impact on sphingolipid profile in the targeted tumor and that significant advances in therapeutic gain with PDT can be attained by combining this modality with adjuvant treatment with ceramide analog LCL29.

Transgenerational effects enhance specific immune response in a wild passerine

Directory of Open Access Journals (Sweden)

Juli Broggi

2016-03-01

Full Text Available Vertebrate mothers transfer diverse compounds to developing embryos that can affect their development and final phenotype (i.e., maternal effects. However, the way such effects modulate offspring phenotype, in particular their immunity, remains unclear. To test the impact of maternal effects on offspring development, we treated wild breeding house sparrows (Passer domesticus in Sevilla, SE Spain with Newcastle disease virus (NDV vaccine. Female parents were vaccinated when caring for first broods, eliciting a specific immune response to NDV. The immune response to the same vaccine, and to the PHA inflammatory test were measured in 11-day-old chicks from their following brood. Vaccinated chicks from vaccinated mothers developed a stronger specific response that was related to maternal NDV antibody concentration while rearing their chicks. The chicks’ carotenoid concentration and total antioxidant capacity in blood were negatively related to NDV antibody concentration, whereas no relation with PHA response was found. Specific NDV antibodies could not be detected in 11-day-old control chicks from vaccinated mothers, implying that maternally transmitted antibodies are not directly involved but may promote offspring specific immunity through a priming effect, while other immunity components remain unaffected. Maternally transmitted antibodies in the house sparrow are short-lived, depend on maternal circulation levels and enhance pre-fledging chick specific immunity when exposed to the same pathogens as the mothers.

A specific primed immune response in Drosophila is dependent on phagocytes.

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Linh N Pham

2007-03-01

Full Text Available Drosophila melanogaster, like other invertebrates, relies solely on its innate immune response to fight invading microbes; by definition, innate immunity lacks adaptive characteristics. However, we show here that priming Drosophila with a sublethal dose of Streptococcus pneumoniae protects against an otherwise-lethal second challenge of S. pneumoniae. This protective effect exhibits coarse specificity for S. pneumoniae and persists for the life of the fly. Although not all microbial challenges induced this specific primed response, we find that a similar specific protection can be elicited by Beauveria bassiana, a natural fly pathogen. To characterize this primed response, we focused on S. pneumoniae-induced protection. The mechanism underlying this protective effect requires phagocytes and the Toll pathway. However, activation of the Toll pathway is not sufficient for priming-induced protection. This work contradicts the paradigm that insect immune responses cannot adapt and will promote the search for similar responses overlooked in organisms with an adaptive immune response.

Relationship between single-event upset immunity and fabrication processes of recent memories

International Nuclear Information System (INIS)

Nemoto, N.; Shindou, H.; Kuboyama, S.; Matsuda, S.; Itoh, H.; Okada, S.; Nashiyama, I.

1999-01-01

Single-Event upset (SEU) immunity for commercial devices were evaluated by irradiation tests using high-energy heavy ions. We show test results and describe the relationship between observed SEU and structures/fabrication processes. We have evaluated single-even upset (SEU) tolerance of recent commercial memory devices using high energy heavy ions in order to find relationship between SEU rate and their fabrication process. It was revealed that the change of the process parameter gives much effect for the SEU rate of the devices. (authors)

Asymmetric T lymphocyte division in the initiation of adaptive immune responses.

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Chang, John T; Palanivel, Vikram R; Kinjyo, Ichiko; Schambach, Felix; Intlekofer, Andrew M; Banerjee, Arnob; Longworth, Sarah A; Vinup, Kristine E; Mrass, Paul; Oliaro, Jane; Killeen, Nigel; Orange, Jordan S; Russell, Sarah M; Weninger, Wolfgang; Reiner, Steven L

2007-03-23

A hallmark of mammalian immunity is the heterogeneity of cell fate that exists among pathogen-experienced lymphocytes. We show that a dividing T lymphocyte initially responding to a microbe exhibits unequal partitioning of proteins that mediate signaling, cell fate specification, and asymmetric cell division. Asymmetric segregation of determinants appears to be coordinated by prolonged interaction between the T cell and its antigen-presenting cell before division. Additionally, the first two daughter T cells displayed phenotypic and functional indicators of being differentially fated toward effector and memory lineages. These results suggest a mechanism by which a single lymphocyte can apportion diverse cell fates necessary for adaptive immunity.

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.

The role of dehydroepiandrosterone on functional innate immune responses to acute stress.

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Prall, Sean P; Larson, Emilee E; Muehlenbein, Michael P

2017-12-01

The androgen dehydroepiandrosterone (DHEA) responds to stress activation, exhibits anti-glucocorticoid properties, and modulates immunity in diverse ways, yet little is known of its role in acute stress responses. In this study, the effects of DHEA and its sulfate ester DHEA-S on human male immune function during exposure to an acute stressor is explored. Variation in DHEA, DHEA-S, testosterone, and cortisol, along with bacterial killing assays, was measured in response to a modified Trier Social Stress test in 27 young adult males. Cortisol was positively related to salivary innate immunity but only for participants who also exhibited high DHEA responses. Additionally, DHEA positively and DHEA-S negatively predicted salivary immunity, but the opposite was observed for serum-based innate immunity. The DHEA response to acute stress appears to be an important factor in stress-mediated immunological responses, with differential effects on immunity dependent upon the presence of other hormones, primarily cortisol and DHEA-S. These results suggest that DHEA plays an important role, alongside other hormones, in modulating immunological shifts during acute stress. Copyright © 2017 John Wiley & Sons, Ltd.

Immunizations with hepatitis B viral antigens and a TLR7/8 agonist adjuvant induce antigen-specific immune responses in HBV-transgenic mice

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Ying Wang

2014-12-01

Conclusions: Immunization with CL097-conjugated HBV-Ag reversed immune tolerance in HBV-Tg mice and induced antigen-specific immune responses. TLR7/8 agonists appear to be potent adjuvants for the induction of antigen-specific Th1 responses in an immune tolerant state.

CD28 Aptamers as Powerful Immune Response Modulators

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Fernando Pastor

2013-01-01

Full Text Available CD28 is one of the main costimulatory receptors responsible for the proper activation of T lymphocytes. We have isolated two aptamers that bind to the CD28 receptor. As a monomer, one of them interfered with the binding of CD28 to its ligand (B7, precluding the costimulatory signal, whereas the other one was inactive. However, dimerization of any of the anti-CD28 aptamers was sufficient to provide an artificial costimulatory signal. No antibody has featured a dual function (i.e., the ability to work as agonist and antagonist to date. Two different agonistic structures were engineered for each anti-CD28 aptamer. One showed remarkably improved costimulatory properties, surpassing the agonistic effect of an anti-CD28 antibody. Moreover, we showed in vivo that the CD28 agonistic aptamer is capable of enhancing the cellular immune response against a lymphoma idiotype and of prolonging survival of mice which receive the aptamer together with an idiotype vaccine. The CD28 aptamers described in this work could be used to modulate the immune response either blocking the interaction with B7 or enhancing vaccine-induced immune responses in cancer immunotherapy.

Immune Response of Multiparous Hyper-Immunized Sows against Peptides from Non-Structural and Structural Proteins of PRRSV

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Edgar Rascón-Castelo

2015-11-01

Full Text Available The purpose of this study was to evaluate the humoral and cellular responses of commercial multiparous and hyper-immunized sows against peptides from non-structural (nsp and structural proteins of porcine reproductive and respiratory syndrome virus (PRRSV. We selected sows with different numbers of parities from a commercial farm. Management practices on this farm include the use of the MLV commercial vaccine four times per year, plus two vaccinations during the acclimation period. The humoral response was evaluated via the antibody recognition of peptides from nsp and structural proteins, and the cellular response was assessed by measuring the frequency of peptide and PRRSV-specific IFN-gamma-secreting cells (IFNγ-SC. Our results show that sows with six parities have more antibodies against peptides from structural proteins than against peptides from nsp. The analysis of the cellular response revealed that the number of immunizations did not affect the frequency of IFNγ-SC and that the response was stronger against peptides from structural proteins (M protein than against nsp (nsp2. In summary, these results demonstrate that multiparous, hyper-immunized sows have a stronger immune humoral response to PRRSV structural peptides than nsp, but no differences in IFNγ-SC against the same peptides were observed.

Role of MicroRNAs in Obesity-Induced Metabolic Disorder and Immune Response

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Hong Zhong

2018-01-01

Full Text Available In all living organisms, metabolic homeostasis and the immune system are the most fundamental requirements for survival. Recently, obesity has become a global public health issue, which is the cardinal risk factor for metabolic disorder. Many diseases emanating from obesity-induced metabolic dysfunction are responsible for the activated immune system, including innate and adaptive responses. Of note, inflammation is the manifest accountant signal. Deeply studied microRNAs (miRNAs have participated in many pathways involved in metabolism and immune responses to protect cells from multiple harmful stimulants, and they play an important role in determining the progress through targeting different inflammatory pathways. Thus, immune response and metabolic regulation are highly integrated with miRNAs. Collectively, miRNAs are the new targets for therapy in immune dysfunction.

Persistent expansion of CD4(+) effector memory T cells in Wegener's granulomatosis

NARCIS (Netherlands)

Abdulahad, W. H.; van der Geld, Y. M.; Stegeman, C. A.; Kallenberg, C. G. M.

In order to test the hypothesis that Wegener's granulomatosis (WG) is associated with an ongoing immune effector response, even in remission, we examined the distribution of peripheral naive and memory T-lymphocytes in this disease, and analyzed the function-related phenotypes of the memory T-cell

Trained innate immunity as underlying mechanism for the long-term, nonspecific effects of vaccines

DEFF Research Database (Denmark)

Blok, Bastiaan A; Arts, Rob J W; van Crevel, Reinout

2015-01-01

An increasing body of evidence shows that the innate immune system has adaptive characteristics that involve a heterologous memory of past insults. Both experimental models and proof-of-principle clinical trials show that innate immune cells, such as monocytes, macrophages, and NK cells, can...... provide protection against certain infections in vaccination models independently of lymphocytes. This process is regulated through epigenetic reprogramming of innate immune cells and has been termed "trained immunity." It has been hypothesized that induction of trained immunity is responsible...... for the protective, nonspecific effects induced by vaccines, such as BCG, measles vaccination, and other whole-microorganism vaccines. In this review, we will present the mechanisms of trained immunity responsible for the long-lasting effects of vaccines on the innate immune system....

[Bone marrow stromal damage mediated by immune response activity].

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Vojinović, J; Kamenov, B; Najman, S; Branković, Lj; Dimitrijević, H

1994-01-01

The aim of this work was to estimate influence of activated immune response on hematopoiesis in vitro, using the experimental model of BCG immunized BALB/c mice and in patients with chronic immunoactivation: long-lasting infections, autoimmunity or malignancy. We correlated changes in long term bone marrow cultures (Dexter) and NBT reduction with appearance of anemia in patients and experimental model of immunization by BCG. Increased spontaneous NBT reduction pointed out role of macrophage activation in bone marrow stroma damage. Long-term bone marrow cultures showed reduced number of hematopoietic cells, with predomination of fibroblasts and loss of fat cells. This results correlated with anemia and leucocytosis with stimulated myelopoiesis in peripheral blood. Activation of immune response, or acting of any agent that directly changes extracellular matrix and cellularity of bone marrow, may result in microenviroment bone marrow damage that modify hematopoiesis.

The Lung Immune Response to Nontypeable Haemophilus influenzae (Lung Immunity to NTHi

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Paul T. King

2015-01-01

Full Text Available Haemophilus influenzae is divided into typeable or nontypeable strains based on the presence or absence of a polysaccharide capsule. The typeable strains (such as type b are an important cause of systemic infection, whilst the nontypeable strains (designated as NTHi are predominantly respiratory mucosal pathogens. NTHi is present as part of the normal microbiome in the nasopharynx, from where it may spread down to the lower respiratory tract. In this context it is no longer a commensal and becomes an important respiratory pathogen associated with a range of common conditions including bronchitis, bronchiectasis, pneumonia, and particularly chronic obstructive pulmonary disease. NTHi induces a strong inflammatory response in the respiratory tract with activation of immune responses, which often fail to clear the bacteria from the lung. This results in recurrent/persistent infection and chronic inflammation with consequent lung pathology. This review will summarise the current literature about the lung immune response to nontypeable Haemophilus influenzae, a topic that has important implications for patient management.

Primary immune system responders to nucleus pulposus cells: evidence for immune response in disc herniation

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K Murai

2010-01-01

Full Text Available Although intervertebral disc herniation and associated sciatica is a common disease, its molecular pathogenesis is not well understood. Immune responses are thought to be involved. This study provides direct evidence that even non-degenerated nucleus pulposus (NP cells elicit immune responses. An in vitro colony forming inhibition assay demonstrated the suppressive effects of autologous spleen cells on NP cells and an in vitro cytotoxicity assay showed the positive cytotoxic effects of natural killer (NK cells and macrophages on NP cells. Non-degenerated rat NP tissues transplanted into wild type rats and immune-deficient mice demonstrated a significantly higher NP cell survival rate in immune-deficient mice. Immunohistochemical staining showed the presence of macrophages and NK cells in the transplanted NP tissues. These results suggest that even non-degenerated autologous NP cells are recognized by macrophages and NK cells, which may have an immunological function in the early phase of disc herniation. These findings contribute to understanding resorption and the inflammatory reaction to disc herniation.

Aging of immune system: Immune signature from peripheral blood lymphocyte subsets in 1068 healthy adults.

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Qin, Ling; Jing, Xie; Qiu, Zhifeng; Cao, Wei; Jiao, Yang; Routy, Jean-Pierre; Li, Taisheng

2016-05-01

Aging is a major risk factor for several conditions including neurodegenerative, cardiovascular diseases and cancer. Functional impairments in cellular pathways controlling genomic stability, and immune control have been identified. Biomarker of immune senescence is needed to improve vaccine response and to develop therapy to improve immune control. To identify phenotypic signature of circulating immune cells with aging, we enrolled 1068 Chinese healthy volunteers ranging from 18 to 80 years old. The decreased naïve CD4+ and CD8+ T cells, increased memory CD4+ or CD8+ T cells, loss of CD28 expression on T cells and reverse trend of CD38 and HLA-DR, were significant for aging of immune system. Conversely, the absolute counts and percentage of NK cells and CD19+B cells maintained stable in aging individuals. The Chinese reference ranges of absolute counts and percentage of peripheral lymphocyte in this study might be useful for future clinical evaluation.

Activity against Mycobacterium tuberculosis with concomitant induction of cellular immune responses by a tetraaza-macrocycle with acetate pendant arms.

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David, S; Ordway, D; Arroz, M J; Costa, J; Delgado, R

2001-01-01

The novel tetraaza-macrocyclic compound 3,7,11-tris(carboxymethyl)-3,7,11,17-tetraaza-bicyclo[11.3.1]heptadeca-1(17),13,15-triene, abbreviated as ac3py14, was investigated for its activity against Mycobacterium tuberculosis and for induction of protective cellular immune responses. Perspective results show that ac3py14 and its Fe3+ 1:1 complex, [Fe(ac3py14)], inhibited radiometric growth of several strains of M. tuberculosis. Inhibition with 25 microg/mL varied from 99% for H37Rv to 80% and above for multiple drug-resistant clinical isolates. The capacity of ac3py14 to elicit a beneficial immune response without cellular apoptosis was assessed and compared to the effects of virulent M. tuberculosis. The present study produces evidence that after stimulation with ac3py14 there was significant production of interferon gamma (IFN-gamma), whereas the production of interleukin-5 (IL-5) remained low, and there was development of a memory population (CD45RO). The level of binding of Annexin V, a marker of apoptosis, was not sufficient to result in toxic effects toward alphabeta and gammadelta T cells and CD14+ macrophages. This preliminary study is the first report of a compound that simultaneously exerts an inhibitory effect against M. tuberculosis and induces factors associated with protective immune responses.

Impaired Memory Retrieval Correlates with Individual Differences in Cortisol Response but Not Autonomic Response

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Tranel, Daniel; Adolphs, Ralph; Buchanan, Tony W.

2006-01-01

Stress can enhance or impair memory performance. Both cortisol release and sympathetic nervous system responses have been implicated in these differential effects. Here we investigated how memory retrieval might be affected by stress-induced cortisol release, independently of sympathetic nervous system stress responses. Thirty-two healthy…

DMPD: Innate immune responses during infection. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available va Correia J. Vaccine. 2004 Dec 6;22 Suppl 1:S25-30. (.png) (.svg) (.html) (.csml) Show Innate immune responses during infection. Pub...medID 15576198 Title Innate immune responses during infection. Authors Ulevitch RJ,

Alcohol, aging, and innate immunity.

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Boule, Lisbeth A; Kovacs, Elizabeth J

2017-07-01

The global population is aging: in 2010, 8% of the population was older than 65 y, and that is expected to double to 16% by 2050. With advanced age comes a heightened prevalence of chronic diseases. Moreover, elderly humans fair worse after acute diseases, namely infection, leading to higher rates of infection-mediated mortality. Advanced age alters many aspects of both the innate and adaptive immune systems, leading to impaired responses to primary infection and poor development of immunologic memory. An often overlooked, yet increasingly common, behavior in older individuals is alcohol consumption. In fact, it has been estimated that >40% of older adults consume alcohol, and evidence reveals that >10% of this group is drinking more than the recommended limit by the National Institute on Alcohol Abuse and Alcoholism. Alcohol consumption, at any level, alters host immune responses, including changes in the number, phenotype, and function of innate and adaptive immune cells. Thus, understanding the effect of alcohol ingestion on the immune system of older individuals, who are already less capable of combating infection, merits further study. However, there is currently almost nothing known about how drinking alters innate immunity in older subjects, despite innate immune cells being critical for host defense, resolution of inflammation, and maintenance of immune homeostasis. Here, we review the effects of aging and alcohol consumption on innate immune cells independently and highlight the few studies that have examined the effects of alcohol ingestion in aged individuals. © Society for Leukocyte Biology.

B Cell Intrinsic Mechanisms Constraining IgE Memory

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Brice Laffleur

2017-11-01

Full Text Available Memory B cells and long-lived plasma cells are key elements of adaptive humoral immunity. Regardless of the immunoglobulin class produced, these cells can ensure long-lasting protection but also long-lasting immunopathology, thus requiring tight regulation of their generation and survival. Among all antibody classes, this is especially true for IgE, which stands as the most potent, and can trigger dramatic inflammatory reactions even when present in minute amounts. IgE responses and memory crucially protect against parasites and toxic components of venoms, conferring selective advantages and explaining their conservation in all mammalian species despite a parallel broad spectrum of IgE-mediated immunopathology. Long-term memory of sensitization and anaphylactic responses to allergens constitute the dark side of IgE responses, which can trigger multiple acute or chronic pathologic manifestations, some punctuated with life-threatening events. This Janus face of the IgE response and memory, both necessary and potentially dangerous, thus obviously deserves the most elaborated self-control schemes.

The Response Dynamics of Recognition Memory: Sensitivity and Bias

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Koop, Gregory J.; Criss, Amy H.

2016-01-01

Advances in theories of memory are hampered by insufficient metrics for measuring memory. The goal of this paper is to further the development of model-independent, sensitive empirical measures of the recognition decision process. We evaluate whether metrics from continuous mouse tracking, or response dynamics, uniquely identify response bias and…

Immune senescence: relative contributions of age and cytomegalovirus infection.

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Andrea Mekker

Full Text Available Immune senescence, defined as the age-associated dysregulation and dysfunction of the immune system, is characterised by impaired protective immunity and decreased efficacy of vaccines. Recent clinical, epidemiological and immunological studies suggest that Cytomegalovirus (CMV infection may be associated with accelerated immune senescence, possibly by restricting the naïve T cell repertoire. However, direct evidence whether and how CMV-infection is implicated in immune senescence is still lacking. In this study, we have investigated whether latent mouse CMV (MCMV infection with or without thymectomy (Tx alters antiviral immunity of young and aged mice. After infection with lymphocytic choriomeningitis virus (LCMV or Vaccinia virus, specific antiviral T cell responses were significantly reduced in old, old MCMV-infected and/or Tx mice compared to young mice. Importantly, control of LCMV replication was more profoundly impaired in aged MCMV-infected mice compared to age-matched MCMV-naïve or young mice. In addition, latent MCMV infection was associated with slightly reduced vaccination efficacy in old Tx mice. In contrast to the prevailing hypothesis of a CMV-mediated restriction of the naïve T cell repertoire, we found similar naïve T cell numbers in MCMV-infected and non-infected mice, whereas ageing and Tx clearly reduced the naïve T cell pool. Instead, MCMV-infection expanded the total CD8(+ T cell pool by a massive accumulation of effector memory T cells. Based on these results, we propose a new model of increased competition between CMV-specific memory T cells and any 'de novo' immune response in aged individuals. In summary, our results directly demonstrate in a mouse model that latent CMV-infection impairs immunity in old age and propagates immune senescence.

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

Emotional Intensity and Emotion Regulation in Response to Autobiographical Memories During Dysphoria

DEFF Research Database (Denmark)

del Palacio Gonzalez, Adriana; Berntsen, Dorthe; Watson, Lynn Ann

2017-01-01

Retrieving personal memories may provoke different emotions and a need for emotion regulation. Emotional responses have been studied scarcely in relation to autobiographical memory retrieval. We examined the emotional response to everyday involuntary (spontaneously arising) and voluntary...... (strategically retrieved) memories, and how this response may be different during dysphoria. Participants (20 dysphoric and 23 non-depressed) completed a structured diary where the intensity of basic emotions and regulation strategies employed upon retrieval of memories were rated. Brooding, memory suppression......, and emotional suppression were higher for all individuals’ involuntary memories than voluntary memories. Negative emotions and regulation strategies were greater for dysphoric individuals for both involuntary and voluntary memories after controlling for the valence of the remembered events. The results provide...

Sex-specific consequences of an induced immune response on reproduction in a moth.

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Barthel, Andrea; Staudacher, Heike; Schmaltz, Antje; Heckel, David G; Groot, Astrid T

2015-12-16

Immune response induction benefits insects in combatting infection by pathogens. However, organisms have a limited amount of resources available and face the dilemma of partitioning resources between immunity and other life-history traits. Since males and females differ in their life histories, sex-specific resource investment strategies to achieve an optimal immune response following an infection can be expected. We investigated immune response induction of females and males of Heliothis virescens in response to the entomopathogenic bacterium Serratia entomophila, and its effects on mating success and the female sexual signal. We found that females had higher expression levels of immune-related genes after bacterial challenge than males. However, males maintained a higher baseline expression of immune-related genes than females. The increased investment in immunity of female moths was negatively correlated with mating success and the female sexual signal. Male mating success was unaffected by bacterial challenge. Our results show that the sexes differed in their investment strategies: females invested in immune defense after a bacterial challenge, indicating facultative immune deployment, whereas males had higher baseline immunity than females, indicating immune maintenance. Interestingly, these differences in investment were reflected in the mate choice assays. As female moths are the sexual signallers, females need to invest resources in their attractiveness. However, female moths appeared to invest in immunity at the cost of reproductive effort.

Perillyl alcohol suppresses antigen-induced immune responses in the lung

International Nuclear Information System (INIS)

Imamura, Mitsuru; Sasaki, Oh; Okunishi, Katsuhide; Nakagome, Kazuyuki; Harada, Hiroaki; Kawahata, Kimito; Tanaka, Ryoichi; Yamamoto, Kazuhiko; Dohi, Makoto

2014-01-01

Highlights: •Perillyl alcohol (POH) is an isoprenoid which inhibits the mevalonate pathway. •We examined whether POH suppresses immune responses with a mouse model of asthma. •POH treatment during sensitization suppressed Ag-induced priming of CD4 + T cells. •POH suppressed airway eosinophila and cytokine production in thoracic lymph nodes. -- Abstract: Perillyl alcohol (POH) is an isoprenoid which inhibits farnesyl transferase and geranylgeranyl transferase, key enzymes that induce conformational and functional changes in small G proteins to conduct signal production for cell proliferation. Thus, it has been tried for the treatment of cancers. However, although it affects the proliferation of immunocytes, its influence on immune responses has been examined in only a few studies. Notably, its effect on antigen-induced immune responses has not been studied. In this study, we examined whether POH suppresses Ag-induced immune responses with a mouse model of allergic airway inflammation. POH treatment of sensitized mice suppressed proliferation and cytokine production in Ag-stimulated spleen cells or CD4 + T cells. Further, sensitized mice received aerosolized OVA to induce allergic airway inflammation, and some mice received POH treatment. POH significantly suppressed indicators of allergic airway inflammation such as airway eosinophilia. Cytokine production in thoracic lymph nodes was also significantly suppressed. These results demonstrate that POH suppresses antigen-induced immune responses in the lung. Considering that it exists naturally, POH could be a novel preventive or therapeutic option for immunologic lung disorders such as asthma with minimal side effects

Inter-donor variation in cell subset specific immune signaling responses in healthy individuals.

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Longo, Diane M; Louie, Brent; Wang, Ena; Pos, Zoltan; Marincola, Francesco M; Hawtin, Rachael E; Cesano, Alessandra

2012-01-01

Single cell network profiling (SCNP) is a multi-parameter flow cytometry based approach that allows for the simultaneous interrogation of intracellular signaling pathways in multiple cell subpopulations within heterogeneous tissues, without the need for individual cell subset isolation. Thus, the technology is extremely well-suited for characterizing the multitude of interconnected signaling pathways and immune cell subpopulations that regulate the function of the immune system. Recently, SCNP was applied to generate a functional map of the healthy human immune cell signaling network by profiling immune signaling pathways downstream of 12 immunomodulators in 7 distinct immune cell subsets within peripheral blood mononuclear cells (PBMCs) from 60 healthy donors. In the study reported here, the degree of inter-donor variation in the magnitude of the immune signaling responses was analyzed. The highest inter-donor differences in immune signaling pathway activity occurred following perturbation of the immune signaling network, rather than in basal signaling. When examining the full panel of immune signaling responses, as one may expect, the overall degree of inter-donor variation was positively correlated (r = 0.727) with the magnitude of node response (i.e. a larger median signaling response was associated with greater inter-donor variation). However, when examining the degree of heterogeneity across cell subpopulations for individual signaling nodes, cell subset specificity in the degree of inter-donor variation was observed for several nodes. For such nodes, relatively weak correlations between inter-donor variation and the magnitude of the response were observed. Further, within the phenotypically distinct subpopulations, a fraction of the immune signaling responses had bimodal response profiles in which (a) only a portion of the cells had elevated phospho-protein levels following modulation and (b) the proportion of responsive cells varied by donor. These data

Variant proteins stimulate more IgM+ GC B-cells revealing a mechanism of cross-reactive recognition by antibody memory.

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Burton, Bronwen R; Tennant, Richard K; Love, John; Titball, Richard W; Wraith, David C; White, Harry N

2018-05-01

Vaccines induce memory B-cells that provide high affinity secondary antibody responses to identical antigens. Memory B-cells can also re-instigate affinity maturation, but how this happens against antigenic variants is poorly understood despite its potential impact on driving broadly protective immunity against pathogens such as Influenza and Dengue. We immunised mice sequentially with identical or variant Dengue-virus envelope proteins and analysed antibody and germinal-centre (GC) responses. Variant protein boosts induced GC with higher proportions of IgM+ B-cells. The most variant protein re-stimulated GCs with the highest proportion of IgM+ cells with the most diverse, least mutated V-genes and with a slower but efficient serum antibody response. Recombinant antibodies from GC B-cells showed a higher affinity for the variant antigen than antibodies from a primary response, confirming a memory origin. This reveals a new process of antibody memory, that IgM memory cells with fewer mutations participate in secondary responses to variant antigens, demonstrating how the hierarchical structure of B-cell memory is used and indicating the potential and limits of cross-reactive antibody based immunity. © 2018, Burton et al.

Immune response in the lungs following oral immunization with bacterial lysates of respiratory pathogens.

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Ruedl, C; Frühwirth, M; Wick, G; Wolf, H

1994-03-01

We have investigated the local immune response of the BALB/c mouse respiratory tract after oral immunization with a bacterial lysate of seven common respiratory pathogens. After two immunization on five consecutive days, we examined the immunoglobulin (immunoglobulin G [IgG], IgM, and IgA) secretion rates of cells isolated from the lungs and compared them with those of spleen cells of orally immunized and nonimmunized animals by using a new test system based on time-resolved fluorescence. The procedure followed the principle of the classical ELISPOT test with nitrocellulose-bottomed microtiter plates, but europium (Eu3+)-linked streptavidin rather than enzyme-conjugated streptavidin was used, with the advantage of quantifying secreted immunoglobulins instead of detecting single antibody-secreting cells. Lymphocytes isolated from the lungs of treated animals revealed significant increases in total and antigen-specific IgA synthesis compared with the rates of the controls, whereas IgG and IgM production rates showed no remarkable differences. In addition, the sera of treated mice revealed higher antigen-specific IgA titers but not increased IgM and IgG levels. We conclude that priming the gut-associated lymphoid tissue with bacterial antigens of pneumotropic microorganisms can elicit an enhanced IgA response in a distant mucosal effector site, such as the respiratory tract, according to the concept of a common mucosa-associated immune system.

Behavioral Fever Drives Epigenetic Modulation of the Immune Response in Fish.

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Boltana, Sebastian; Aguilar, Andrea; Sanhueza, Nataly; Donoso, Andrea; Mercado, Luis; Imarai, Monica; Mackenzie, Simon

2018-01-01

Ectotherms choose the best thermal conditions to mount a successful immune response, a phenomenon known as behavioral fever. The cumulative evidence suggests that behavioral fever impacts positively upon lymphocyte proliferation, inflammatory cytokine expression, and other immune functions. In this study, we have explored how thermal choice during infection impacts upon underpinning molecular processes and how temperature increase is coupled to the immune response. Our results show that behavioral fever results in a widespread, plastic imprint on gene regulation, and lymphocyte proliferation. We further explored the possible contribution of histone modification and identified global associations between temperature and histone changes that suggest epigenetic remodeling as a result of behavioral fever. Together, these results highlight the critical importance of thermal choice in mobile ectotherms, particularly in response to an infection, and demonstrate the key role of epigenetic modification to orchestrate the thermocoupling of the immune response during behavioral fever.

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

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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.

CCR6-dependent positioning of memory B cells is essential for their ability to mount a recall response to antigen

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Elgueta, Raul; Marks, Ellen; Nowak, Elizabeth; Menezes, Shinelle; Benson, Micah; Raman, Vanitha S.; Ortiz, Carla; O’Connell, Samuel; Hess, Henry; Lord, Graham M.; Noelle, Randolph

2014-01-01

Chemokine-dependent localization of specific B cell subsets within the immune microarchitecture is essential to insure successful cognate interactions. While cognate interactions between T cells and memory B cells (Bmem)5 are essential for the secondary humoral immune responses, the chemokine response patterns of Bmem cells are largely unknown. In contrast to naïve B cells, this study shows that antigen-specific Bmem cells have heightened expression of CCR6 and a selective chemotactic response to the CCR6 ligand, CCL20. While CCR6 appears be non-essential for the initial clonal expansion and maintenance of Bmem, CCR6 is essential for the ability of Bmem to respond to a recall response to their cognate antigen. This dependency was deemed intrinsic by studies in CCR6-deficient mice and in bone-marrow chimeric mice where CCR6 deficiency was limited to the B cell lineage. Finally, the mis-positioning of CCR6-deficient Bmem was revealed by immunohistological analysis with an altered distribution of CCR6-deficient Bmem from the marginal and perifollicular to the follicular/germinal center area. PMID:25505290

Host control of malaria infections: constraints on immune and erythropoeitic response kinetics.

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Philip G McQueen

2008-08-01

Full Text Available The two main agents of human malaria, Plasmodium vivax and Plasmodium falciparum, can induce severe anemia and provoke strong, complex immune reactions. Which dynamical behaviors of host immune and erythropoietic responses would foster control of infection, and which would lead to runaway parasitemia and/or severe anemia? To answer these questions, we developed differential equation models of interacting parasite and red blood cell (RBC populations modulated by host immune and erythropoietic responses. The model immune responses incorporate both a rapidly responding innate component and a slower-responding, long-term antibody component, with several parasite developmental stages considered as targets for each type of immune response. We found that simulated infections with the highest parasitemia tended to be those with ineffective innate immunity even if antibodies were present. We also compared infections with dyserythropoiesis (reduced RBC production during infection to those with compensatory erythropoiesis (boosted RBC production or a fixed basal RBC production rate. Dyserythropoiesis tended to reduce parasitemia slightly but at a cost to the host of aggravating anemia. On the other hand, compensatory erythropoiesis tended to reduce the severity of anemia but with enhanced parasitemia if the innate response was ineffective. For both parasite species, sharp transitions between the schizont and the merozoite stages of development (i.e., with standard deviation in intra-RBC development time immune response, though P. vivax attacks a much smaller subset of RBCs. Since most P. vivax infections are nonlethal (if debilitating clinically, this suggests that P

Delicate regulation of the cGAS-MITA-mediated innate immune response.

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Luo, Wei-Wei; Shu, Hong-Bing

2018-02-19

Although it has long been demonstrated that cytosolic DNA is a potent immune stimulant, it is only in recent years that the molecular mechanisms of DNA-stimulated innate immune responses have emerged. Studies have established critical roles for the DNA sensor cyclic GMP-AMP synthase (cGAS) and the adapter protein MITA/STING in the innate immune response to cytosolic DNA or DNA viruses. Although the regulation of cGAS-MITA/STING-mediated signaling remains to be fully investigated, understanding the processes involved may help to explain the mechanisms of innate immune signaling events and perhaps autoinflammatory diseases and to provide potential therapeutic targets for drug intervention. In this review, we summarize recent progress on the regulation of the cGAS-MITA/STING-mediated innate immune response to DNA viruses at the organelle-trafficking, post-translational and transcriptional levels.Cellular & Molecular Immunology advance online publication, 19 February 2018; doi:10.1038/cmi.2016.51.

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,

Immune Curbing of Cancer Stem Cells by CTLs Directed to NANOG

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Christina Wefers

2018-06-01

Full Text Available Cancer stem cells (CSCs have been identified as the source of tumor growth and disease recurrence. Eradication of CSCs is thus essential to achieve durable responses, but CSCs are resistant to current anti-tumor therapies. Novel therapeutic approaches that specifically target CSCs will, therefore, be crucial to improve patient outcome. Immunotherapies, which boost the body’s own immune system to eliminate cancerous cells, could be an alternative approach to target CSCs. Vaccines of dendritic cells (DCs loaded with tumor antigens can evoke highly specific anti-tumor T cell responses. Importantly, DC vaccination also promotes immunological memory formation, paving the way for long-term cancer control. Here, we propose a DC vaccination that specifically targets CSCs. DCs loaded with NANOG peptides, a protein required for maintaining stem cell properties, could evoke a potent anti-tumor immune response against CSCs. We hypothesize that the resulting immunological memory will also control newly formed CSCs, thereby preventing disease recurrence.

Immunological memory: What's in a name?

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Pradeu, Thomas; Du Pasquier, Louis

2018-05-01

Immunological memory is one of the core topics of contemporary immunology. Yet there are many discussions about what this concept precisely means, which components of the immune system display it, and in which phyla it exists. Recent years have seen the multiplication of claims that immunological memory can be found in "innate" immune cells and in many phyla beyond vertebrates (including invertebrates, plants, but also bacteria and archaea), as well as the multiplication of concepts to account for these phenomena, such as "innate immune memory" or "trained immunity". The aim of this critical review is to analyze these recent claims and concepts, and to distinguish ideas that have often been misleadingly associated, such as memory, adaptive immunity, and specificity. We argue that immunological memory is a gradual and multidimensional phenomenon, irreducible to any simple dichotomy, and we show why adopting this new view matters from an experimental and therapeutic point of view. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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.

Glucocorticoids mediate stress-induced impairment of retrieval of stimulus-response memory.

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Atsak, Piray; Guenzel, Friederike M; Kantar-Gok, Deniz; Zalachoras, Ioannis; Yargicoglu, Piraye; Meijer, Onno C; Quirarte, Gina L; Wolf, Oliver T; Schwabe, Lars; Roozendaal, Benno

2016-05-01

Acute stress and elevated glucocorticoid hormone levels are well known to impair the retrieval of hippocampus-dependent 'declarative' memory. Recent findings suggest that stress might also impair the retrieval of non-hippocampal memories. In particular, stress shortly before retention testing was shown to impair the retrieval of striatal stimulus-response associations in humans. However, the mechanism underlying this stress-induced retrieval impairment of non-hippocampal stimulus-response memory remains elusive. In the present study, we investigated whether an acute elevation in glucocorticoid levels mediates the impairing effects of stress on retrieval of stimulus-response memory. Male Sprague-Dawley rats were trained on a stimulus-response task in an eight-arm radial maze until they learned to associate a stimulus, i.e., cue, with a food reward in one of the arms. Twenty-four hours after successful acquisition, they received a systemic injection of vehicle, corticosterone (1mg/kg), the corticosterone-synthesis inhibitor metyrapone (35mg/kg) or were left untreated 1h before retention testing. We found that the corticosterone injection impaired the retrieval of stimulus-response memory. We further found that the systemic injection procedure per se was stressful as the vehicle administration also increased plasma corticosterone levels and impaired the retrieval of stimulus-response memory. However, memory retrieval was not impaired when rats were tested 2min after the systemic vehicle injection, before any stress-induced elevation in corticosterone levels had occurred. Moreover, metyrapone treatment blocked the effect of injection stress on both plasma corticosterone levels and memory retrieval impairment, indicating that the endogenous corticosterone response mediates the stress-induced memory retrieval impairment. None of the treatments affected rats' locomotor activity or motivation to search for the food reward within the maze. These findings show that stress

Escaping deleterious immune response in their hosts: lessons from trypanosomatids

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Anne eGeiger

2016-05-01

Full Text Available The Trypanosomatidae family includes the genera Trypanosoma and Leishmania, protozoan parasites displaying complex digenetic life cycles requiring a vertebrate host and an insect vector. Trypanosoma brucei gambiense, T. cruzi and Leishmania spp are important human pathogens causing Human African Trypanosomiasis (HAT or Sleeping Sickness, Chagas’ disease, and various clinical forms of Leishmaniasis, respectively. They are transmitted to humans by tsetse flies, triatomine bugs or sandflies and affect millions of people worldwide.In humans, extracellular African trypanosomes (T. brucei evade the hosts’ immune defences, allowing their transmission to the next host, via the tsetse vector. By contrast, T. cruzi and Leishmania sp. have developed a complex intracellular lifestyle, also preventing several mechanisms to circumvent the host’s immune response.This review seeks to set out the immune evasion strategies developed by the different trypanosomatids resulting from parasite-host interactions and, will focus on: clinical and epidemiological importance of diseases; life cycles: parasites-hosts-vectors; innate immunity: key steps for trypanosomatids in invading hosts; deregulation of antigen presenting cells; disruption of efficient specific immunity; and the immune responses used for parasite proliferation.

Escaping Deleterious Immune Response in Their Hosts: Lessons from Trypanosomatids

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Geiger, Anne; Bossard, Géraldine; Sereno, Denis; Pissarra, Joana; Lemesre, Jean-Loup; Vincendeau, Philippe; Holzmuller, Philippe

2016-01-01

The Trypanosomatidae family includes the genera Trypanosoma and Leishmania, protozoan parasites displaying complex digenetic life cycles requiring a vertebrate host and an insect vector. Trypanosoma brucei gambiense, Trypanosoma cruzi, and Leishmania spp. are important human pathogens causing human African trypanosomiasis (HAT or sleeping sickness), Chagas’ disease, and various clinical forms of Leishmaniasis, respectively. They are transmitted to humans by tsetse flies, triatomine bugs, or sandflies, and affect millions of people worldwide. In humans, extracellular African trypanosomes (T. brucei) evade the hosts’ immune defenses, allowing their transmission to the next host, via the tsetse vector. By contrast, T. cruzi and Leishmania sp. have developed a complex intracellular lifestyle, also preventing several mechanisms to circumvent the host’s immune response. This review seeks to set out the immune evasion strategies developed by the different trypanosomatids resulting from parasite–host interactions and will focus on: clinical and epidemiological importance of diseases; life cycles: parasites–hosts–vectors; innate immunity: key steps for trypanosomatids in invading hosts; deregulation of antigen-presenting cells; disruption of efficient specific immunity; and the immune responses used for parasite proliferation. PMID:27303406

Monocyte Chemotactic Protein 1 in Plasma from Soluble Leishmania Antigen-Stimulated Whole Blood as a Potential Biomarker of the Cellular Immune Response to Leishmania infantum

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Ana V. Ibarra-Meneses

2017-09-01

Full Text Available New biomarkers are needed to identify asymptomatic Leishmania infection as well as immunity following vaccination or treatment. With the aim of finding a robust biomarker to assess an effective cellular immune response, monocyte chemotactic protein 1 (MCP-1 was examined in plasma from soluble Leishmania antigen (SLA-stimulated whole blood collected from subjects living in a Leishmania infantum-endemic area. MCP-1, expressed 110 times more strongly than IL-2, identified 87.5% of asymptomatic subjects and verified some asymptomatic subjects close to the cutoff. MCP-1 was also significantly elevated in all patients cured of visceral leishmaniasis (VL, unlike IL-2, indicating the specific memory response generated against Leishmania. These results show MCP-1 to be a robust candidate biomarker of immunity that could be used as a marker of cure and to both select and follow the population in vaccine phase I–III human clinical trials with developed rapid, easy-to-use field tools.

Study of the integrated immune response induced by an inactivated EV71 vaccine.

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Longding Liu

Full Text Available Enterovirus 71 (EV71, a major causative agent of hand-foot-and-mouth disease (HFMD, causes outbreaks among children in the Asia-Pacific region. A vaccine is urgently needed. Based on successful pre-clinical work, phase I and II clinical trials of an inactivated EV71 vaccine, which included the participants of 288 and 660 respectively, have been conducted. In the present study, the immune response and the correlated modulation of gene expression in the peripheral blood mononuclear cells (PBMCs of 30 infants (6 to 11 months immunized with this vaccine or placebo and consented to join this study in the phase II clinical trial were analyzed. The results showed significantly greater neutralizing antibody and specific T cell responses in vaccine group after two inoculations on days 0 and 28. Additionally, more than 600 functional genes that were up- or down-regulated in PBMCs were identified by the microarray assay, and these genes included 68 genes associated with the immune response in vaccine group. These results emphasize the gene expression profile of the immune system in response to an inactivated EV71 vaccine in humans and confirmed that such an immune response was generated as the result of the positive mobilization of the immune system. Furthermore, the immune response was not accompanied by the development of a remarkable inflammatory response.NCT01391494 and NCT01512706.

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

Immune response to uv-induced tumors: transplantation immunity and lymphocyte populations exhibiting anti-tumor activity

International Nuclear Information System (INIS)

Streeter, P.R.

1985-01-01

Ultraviolet light-induced murine skin tumors were analyzed for their ability to induce tumor-specific and cross-protective transplantation immunity in immunocompetent syngeneic mice. These studies revealed that progressor UV-tumors, like regressor UV-tumors, possess tumor-specific transplantation antigens. Cross-protective transplantation immunity to UV-tumors, however, was associated with sensitization to the serum used to culture the tumor lines rather than to cross-reactive or common determinants on UV-tumors. An analysis of the cytolytic activity of lymphocytes from the spleens of mice immunized with either regressor or progressor UV-tumors revealed a striking difference between the two immune splenocyte populations. From regressor tumor-immune animals, cytolytic T (Tc) lymphocytes with specificity for the immunizing tumor were found. However, the analysis of splenic lymphocytes from progressor tumor immune animals revealed no such effector cells. To more effectively examine those lymphocytes exhibiting cytolytic activity in vitro, T lymphocyte cloning technology was used as a means of isolating homogeneous lymphocyte populations with the effector activities described above. The mechanisms where NK cells and other nonspecific effector cells could be induced in tumor-immune animals are discussed in the context of class II restricted immune responses

Apoptosis of antigen-specific CTLs contributes to low immune response in gut-associated lymphoid tissue post vaccination.

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Shimada, Masaru; Yoshizaki, Shinji; Ichino, Motohide; Klinman, Dennis M; Okuda, Kenji

2014-09-08

The gut-associated lymphoid tissue (GALT) represents a major reservoir of HIV in infected individuals. Vaccines can induce strong systemic immune responses but these have less impact on CD4 T cells activity and numbers in GALT. In this study, we vaccinated mice with an adenovirus vector that expressed the envelope gene from HIV and observed immune responses in the peripheral blood, spleen, liver, mesenteric lymph nodes, and Peyer's patches. We found that (1) the number of HIV-specific CD8 T cells was dramatically lower in GALT than in other tissues; (2) the programmed cell death protein-1 (PD-1) was expressed at high levels in HIV-specific CD8 T cells including memory T cells in GALT; and (3) high levels of HIV-specific CD8 T cell apoptosis were occurring in GALT. These results suggest that contributing to GALT becoming an HIV reservoir during infection is a combination of exhaustion and/or dysfunction of HIV-specific CTLs at that site. These results emphasize the importance of developing of an effective mucosal vaccine against HIV. Copyright © 2014 Elsevier Ltd. All rights reserved.

Role of IL-12 and IFN-γ in immune response to toxoplasma gondii infection

International Nuclear Information System (INIS)

Moawad, M.A.F.; ElGawish, M.A.M.

2004-01-01

Interlenkin 12 (IL-12) is a potent immunoregulatory molecule that is critically involved in a wide range of diseases. In several murine models of intracellular infection, endogenous IL-12 has been shown to be crucial for the generation of a protective Th1 response in a primary infection for a intracellular pathogens. Interferon-gamma (IFN-γ) is also an important mediator of cellular immunity against microbial pathogens and tumor cells due to its potent capacity to activate macrophages for enhanced cytotoxicity. The aim of the present study is to evaluate the immune response to toxoplasma gondii after primary inflection (infected groups and secondary infection (re-infected groups for over 19 weeks (the time of the experiment). the evaluation was assessed by measurements of levels of IL-12 and IFN-γ using ELISA technique in the sera of these infected rats. The results demonstrated that the primary immune response induced a fluctuation in the levels of IL-12 in the sera of infected rats, which reached maximum value of 122.6 ±1.4 pg/ml after 15 weeks of primary infection. While, in the challenged groups (secondary immune response, re-infected groups) the levels of IL-12 were generally lower than that of the primary immune response. On the other hand, IFN-γ levels increased significantly in the secondary immune response (re-infected groups) as compared to primary immune response 9 infected groups) In conclusion, the results suggest that IL-12 might have a role in the defense mechanism against intracellular infection with T-gondii especially in primary immune response than in the secondary immune response. This is in contrast to IFN-γ that takes the up-hand in secondary immune response to T-gondii infection

The basics and advances of immunomodulators and antigen presentation: a key to development of potent memory response against pathogens.

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Garai, Preeti; Gogoi, Mayuri; Gopal, Ganesh; Radhakrishnan, Yashwanth; Nandakumar, Krishnadas Subhadramma; Chakravortty, Dipshikha

2014-10-01

Immunomodulators are agents, which can modulate the immune response to specific antigens, while causing least toxicity to the host system. Being part of the modern vaccine formulations, these compounds have contributed remarkably to the field of therapeutics. Despite the successful record maintained by these agents, the requirement of novel immunomodulators keeps increasing due to the increasing severity of diseases. Hence, research regarding the same holds great importance. In this review, we discuss the role of immunomodulators in improving performance of various vaccines used for counteracting most threatening infectious diseases, mechanisms behind their action and criteria for development of novel immunomodulators. Understanding the molecular mechanisms underlying immune response is a prerequisite for development of effective therapeutics as these are often exploited by pathogens for their own propagation. Keeping this in mind, the present research in the field of immunotherapy focuses on developing immunomodulators that would not only enhance the protection against pathogen, but also generate a long-term memory response. With the introduction of advanced formulations including combination of different kinds of immunomodulators, one can expect tremendous success in near future.

Immune responses accelerate ageing: proof-of-principle in an insect model.

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E Rhiannon Pursall

Full Text Available The pathology of many of the world's most important infectious diseases is caused by the immune response. Additionally age-related disease is often attributed to inflammatory responses. Consequently a reduction in infections and hence inflammation early in life has been hypothesized to explain the rise in lifespan in industrialized societies. Here we demonstrate experimentally for the first time that eliciting an immune response early in life accelerates ageing. We use the beetle Tenebrio molitor as an inflammation model. We provide a proof of principle for the effects of early infection on morbidity late in life and demonstrate a long-lasting cost of immunopathology. Along with presenting a proof-of-principle study, we discuss a mechanism for the apparently counter-adaptive persistence of immunopathology in natural populations. If immunopathology from early immune response only becomes costly later in life, natural selection on reducing self-harm would be relaxed, which could explain the presence of immune self-harm in nature.

Feasibility of measuring memory response to increasing dexmedetomidine sedation in children.

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Mason, K P; Kelhoffer, E R; Prescilla, R; Mehta, M; Root, J C; Young, V J; Robinson, F; Veselis, R A

2017-02-01

The memory effect of dexmedetomidine has not been prospectively evaluated in children. We evaluated the feasibility of measuring memory and sedation responses in children during dexmedetomidine sedation for non-painful radiological imaging studies. Secondarily, we quantified changes in memory in relation to the onset of sedation. A 10 min bolus of dexmedetomidine (2 mcg kg -1 ) was given to children as they named simple line drawings every five s. The absence of sedation was identified as any verbal response, regardless of correctness. After recovery, recognition memory was tested with correct Yes/No recognitions (50% novel pictures) and was matched to sedation responses during the bolus period (subsequent memory paradigm). Of 64 accruals, 30 children (mean [SD]6.1 (1.2) yr, eight male) received dexmedetomidine and completed all study tasks. Individual responses were able to be modelled successfully in the 30 children completing all the study tasks, demonstrating feasibility of this approach. Children had 50% probability of verbal response at five min 40 s after infusion start, whereas 50% probability of subsequent recognition memory occurred sooner at four min five s. Quantifying memory and sedation effects during dexmedetomidine infusion in verbal children was possible and demonstrated that memory function was present until shortly before verbal unresponsiveness occurred. This is the first study to investigate the effect of dexmedetomidine on memory in children. NCT 02354378. © The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Protection against Pertussis in Humans Correlates to Elevated Serum Antibodies and Memory B Cells

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Valentina Marcellini

2017-09-01

Full Text Available Pertussis is a respiratory infection caused by Bordetella pertussis that may be particularly severe and even lethal in the first months of life when infants are still too young to be vaccinated. Adults and adolescents experience mild symptoms and are the source of infection for neonates. Adoptive maternal immunity does not prevent pertussis in the neonate. We compared the specific immune response of mothers of neonates diagnosed with pertussis and mothers of control children. We show that women have pre-existing pertussis-specific antibodies and memory B cells and react against the infection with a recall response increasing the levels specific serum IgG, milk IgA, and the frequency of memory B cells of all isotypes. Thus, the maternal immune system is activated in response to pertussis and effectively prevents the disease indicating that the low levels of pre-formed serum antibodies are insufficient for protection. For this reason, memory B cells play a major role in the adult defense. The results of this study suggest that new strategies for vaccine design should aim at increasing long-lived plasma cells and their antibodies.

Humoral and cellular immune responses to modified hepatitis B ...

African Journals Online (AJOL)

Purpose: To evaluate the immunogenicity and types of immune response of a quality-controlled modified recombinant hepatitis B surface antigen (HBsAg) plasmid encoding HBsAg in mice. Methods: The characterized plasmid DNA was used in the immunization of Balb/c mice. Three groups of mice were intramuscularly ...

Perillyl alcohol suppresses antigen-induced immune responses in the lung

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Imamura, Mitsuru; Sasaki, Oh; Okunishi, Katsuhide; Nakagome, Kazuyuki; Harada, Hiroaki; Kawahata, Kimito; Tanaka, Ryoichi; Yamamoto, Kazuhiko [Department of Allergy and Rheumatology, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Dohi, Makoto, E-mail: mdohi-tky@umin.ac.jp [Department of Allergy and Rheumatology, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Institute of Respiratory Immunology, Shibuya Clinic for Respiratory Diseases and Allergology, Tokyo (Japan)

2014-01-03

Highlights: •Perillyl alcohol (POH) is an isoprenoid which inhibits the mevalonate pathway. •We examined whether POH suppresses immune responses with a mouse model of asthma. •POH treatment during sensitization suppressed Ag-induced priming of CD4{sup +} T cells. •POH suppressed airway eosinophila and cytokine production in thoracic lymph nodes. -- Abstract: Perillyl alcohol (POH) is an isoprenoid which inhibits farnesyl transferase and geranylgeranyl transferase, key enzymes that induce conformational and functional changes in small G proteins to conduct signal production for cell proliferation. Thus, it has been tried for the treatment of cancers. However, although it affects the proliferation of immunocytes, its influence on immune responses has been examined in only a few studies. Notably, its effect on antigen-induced immune responses has not been studied. In this study, we examined whether POH suppresses Ag-induced immune responses with a mouse model of allergic airway inflammation. POH treatment of sensitized mice suppressed proliferation and cytokine production in Ag-stimulated spleen cells or CD4{sup +} T cells. Further, sensitized mice received aerosolized OVA to induce allergic airway inflammation, and some mice received POH treatment. POH significantly suppressed indicators of allergic airway inflammation such as airway eosinophilia. Cytokine production in thoracic lymph nodes was also significantly suppressed. These results demonstrate that POH suppresses antigen-induced immune responses in the lung. Considering that it exists naturally, POH could be a novel preventive or therapeutic option for immunologic lung disorders such as asthma with minimal side effects.

Mycobacterium tuberculosis co-operonic PE32/PPE65 proteins alter host immune responses by hampering Th1 response

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Mohd eKhubaib

2016-05-01

Full Text Available PE/PPE genes, present in cluster with ESAT-6 like genes, are suspected to have a role in antigenic variation and virulence of Mycobacterium tuberculosis. Their roles in immune evasion and immune modulation of host are also well documented. We present evidence that PE32/PPE65 present within the RD8 region are co-operonic, co-transcribed and co-translated, and play role in modulating host immune responses. Experiments with macrophage cell lines revealed that this protein complex suppresses pro-inflammatory cytokines such as TNF-α and IL-6 whereas also inducing high expression of anti-inflammatory IL-10. Immunization of mice with these recombinant proteins dampens an effective Th1 response as evident from reduced frequency of IFN-g and IL-2 producing CD4+ and CD8+ T cells. IgG sub-typing from serum of immunized mice revealed high levels of IgG1 when compared with IgG2a and IgG2b. Further IgG1/IgG2a ratio clearly demonstrated that the protein complex manipulates the host immune response favourable to the pathogen. Our results demonstrate that the co-transcribed and co-translated PE32 and PPE65 antigens are involved specifically in modulating anti-mycobacterial host immune response by hampering Th1 response.

A modified live canine parvovirus vaccine. II. Immune response.

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Carmichael, L E; Joubert, J C; Pollock, R V

1983-01-01

The safety and efficacy of an attenuated canine parvovirus (A-CPV) vaccine was evaluated in both experimental and in field dogs. After parenteral vaccination, seronegative dogs developed hemagglutination-inhibition (HI) antibody titers as early as postvaccination (PV) day 2. Maximal titers occurred within 1 week. Immunity was associated with the persistence of HI antibody titers (titers greater than 80) that endured at least 2 years. Immune dogs challenged with virulent CPV did not shed virus in their feces. The A-CPV vaccine did not cause illness alone or in combination with living canine distemper (CD) and canine adenovirus type-2 (CAV-2) vaccines, nor did it interfere with the immune response to the other viruses. A high rate (greater than 98%) of immunity was engendered in seronegative pups. In contrast, maternal antibody interfered with the active immune response to the A-CPV. More than 95% of the dogs with HI titers less than 10 responded to the vaccine, but only 50% responded when titers were approximately 20. No animal with a titer greater than 80 at the time of vaccination became actively immunized. Susceptibility to virulent CPV during that period when maternal antibody no longer protects against infection, but still prevents active immunization, is the principal cause of vaccinal failure in breeding kennels where CPV is present. Reduction, but not complete elimination, of CPV disease in large breeding kennels occurred within 1-2 months of instituting an A-CPV vaccination program.

Maternal inflammation induces immune activation of fetal microglia and leads to disrupted microglia immune responses, behavior, and learning performance in adulthood.

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Schaafsma, Wandert; Basterra, Laura Bozal; Jacobs, Sabrina; Brouwer, Nieske; Meerlo, Peter; Schaafsma, Anne; Boddeke, Erik W G M; Eggen, Bart J L

2017-10-01

Maternal inflammation during pregnancy can have detrimental effects on embryonic development that persist during adulthood. However, the underlying mechanisms and insights in the responsible cell types are still largely unknown. Here we report the effect of maternal inflammation on fetal microglia, the innate immune cells of the central nervous system (CNS). In mice, a challenge with LPS during late gestation stages (days 15-16-17) induced a pro-inflammatory response in fetal microglia. Adult whole brain microglia of mice that were exposed to LPS during embryonic development displayed a persistent reduction in pro-inflammatory activation in response to a re-challenge with LPS. In contrast, hippocampal microglia of these mice displayed an increased inflammatory response to an LPS re-challenge. In addition, a reduced expression of brain-derived neurotrophic factor (BDNF) was observed in hippocampal microglia of LPS-offspring. Microglia-derived BDNF has been shown to be important for learning and memory processes. In line with these observations, behavioral- and learning tasks with mice that were exposed to maternal inflammation revealed reduced home cage activity, reduced anxiety and reduced learning performance in a T-maze. These data show that exposure to maternal inflammation during late gestation results in long term changes in microglia responsiveness during adulthood, which is different in nature in hippocampus compared to total brain microglia. Copyright © 2017 Elsevier Inc. All rights reserved.

Nanotechnology, neuromodulation & the immune response: discourse, materiality & ethics.

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Fins, Joseph J

2015-04-01

Drawing upon the American Pragmatic tradition in philosophy and the more recent work of philosopher Karen Barad, this paper examines how scientific problems are both obscured, and resolved by our use of language describing the natural world. Using the example of the immune response engendered by neural implants inserted in the brain, the author explains how this discourse has been altered by the advent of nanotechnology methods and devices which offer putative remedies that might temper the immune response in the central nervous system. This emergent nanotechnology has altered this problem space and catalyzed one scientific community to acknowledge a material reality that was always present, if not fully acknowledged.

Cell mediated immune response in human antirabies revaccination

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Débora Regina Veiga

1987-04-01

Full Text Available The occurrence of secondary cell mediated immune response (CMI in human antirabies immunization was studied. The Puenzalida & Palácios vaccine was used because it is routinely used in Brazil. CMI was evaluated by lymphoblastic transformation indices obtained in whole blood culture in the presence of rabies and control (nervous tissue antigens. Eleven volunteers submitted to revaccination constituted the group under study, while three other volunteers submitted primo vaccination were utilized as control group. A clear secondary CMI to rabies antigen was detected in all the revaccinated volunteers who showed earlier and more intense response than the control group. Response to the control antigen, however, present in all the components of the first group was not detectable in two out of the three primovaccinated and very low in the third one.

High-dimensional analysis of the aging immune system: verification of age-associated differences in immune signaling responses in healthy donors.

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Longo, Diane M; Louie, Brent; Ptacek, Jason; Friedland, Greg; Evensen, Erik; Putta, Santosh; Atallah, Michelle; Spellmeyer, David; Wang, Ena; Pos, Zoltan; Marincola, Francesco M; Schaeffer, Andrea; Lukac, Suzanne; Railkar, Radha; Beals, Chan R; Cesano, Alessandra; Carayannopoulos, Leonidas N; Hawtin, Rachael E

2014-06-21

Single-cell network profiling (SCNP) is a multiparametric flow cytometry-based approach that simultaneously measures evoked signaling in multiple cell subsets. Previously, using the SCNP approach, age-associated immune signaling responses were identified in a cohort of 60 healthy donors. In the current study, a high-dimensional analysis of intracellular signaling was performed by measuring 24 signaling nodes in 7 distinct immune cell subsets within PBMCs in an independent cohort of 174 healthy donors [144 elderly (>65 yrs); 30 young (25-40 yrs)]. Associations between age and 9 immune signaling responses identified in the previously published 60 donor cohort were confirmed in the current study. Furthermore, within the current study cohort, 48 additional immune signaling responses differed significantly between young and elderly donors. These associations spanned all profiled modulators and immune cell subsets. These results demonstrate that SCNP, a systems-based approach, can capture the complexity of the cellular mechanisms underlying immunological aging. Further, the confirmation of age associations in an independent donor cohort supports the use of SCNP as a tool for identifying reproducible predictive biomarkers in areas such as vaccine response and response to cancer immunotherapies.

RTS,S/AS01E Malaria Vaccine Induces Memory and Polyfunctional T Cell Responses in a Pediatric African Phase III Trial

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Gemma Moncunill

2017-08-01

Full Text Available Comprehensive assessment of cellular responses to the RTS,S/AS01E vaccine is needed to understand potential correlates and ultimately mechanisms of protection against malaria disease. Cellular responses recognizing the RTS,S/AS01E-containing circumsporozoite protein (CSP and Hepatitis B surface antigen (HBsAg were assessed before and 1 month after primary vaccination by intracellular cytokine staining and 16-color flow cytometry in 105 RTS,S/AS01-vaccinated and 74 rabies-vaccinated participants (controls in a pediatric phase III trial in Africa. RTS,S/AS01E-vaccinated children had significantly higher frequencies of CSP- and HBsAg-specific CD4+ T cells producing IL-2, TNF-α, and CD40L and HBsAg-specific CD4+ T producing IFN-γ and IL-17 than baseline and the control group. Vaccine-induced responses were identified in both central and effector memory (EM compartments. EM CD4+ T cells expressing IL-4 and IL-21 were detected recognizing both vaccine antigens. Consistently higher response rates to both antigens in RTS,S/AS01E-vaccinated than comparator-vaccinated children were observed. RTS,S/AS01E induced polyfunctional CSP- and HBsAg-specific CD4+ T cells, with a greater degree of polyfunctionality in HBsAg responses. In conclusion, RTS,S/AS01E vaccine induces T cells of higher functional heterogeneity and polyfunctionality than previously characterized. Responses detected in memory CD4+ T cell compartments may provide correlates of RTS,S/AS01-induced immunity and duration of protection in future correlates of immunity studies.

Localization of functional memory B cells at sites of antigen localization and its relationship to local aspects of immunological memory

International Nuclear Information System (INIS)

Ponzio, N.M.; Baine, Y.; Thorbecke, G.J.

1980-01-01

Experiments are described which have been designed to test whether antigen in a draining lymph node can mediate local accumulation of passively transferred antigen-specific memory B cells, using recipients whose own immune response is inhibited via γ-irradiation or by injection of cyclophosphamide. (Auth.)

Sm29, but not Sm22.6 retains its ability to induce a protective immune response in mice previously exposed to a Schistosoma mansoni infection.

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Clarice Carvalho Alves

2015-02-01

Full Text Available BACKGROUND: A vaccine against schistosomiasis would have a great impact in disease elimination. Sm29 and Sm22.6 are two parasite tegument proteins which represent promising antigens to compose a vaccine. These antigens have been associated with resistance to infection and reinfection in individuals living in endemic area for the disease and induced partial protection when evaluated in immunization trials using naïve mice. METHODOLOGY/PRINCIPALS FINDINGS: In this study we evaluated rSm29 and rSm22.6 ability to induce protection in Balb/c mice that had been previously infected with S. mansoni and further treated with Praziquantel. Our results demonstrate that three doses of the vaccine containing rSm29 were necessary to elicit significant protection (26%-48%. Immunization of mice with rSm29 induced a significant production of IL-2, IFN-γ, IL-17, IL-4; significant production of specific antibodies; increased percentage of CD4+ central memory cells in comparison with infected and treated saline group and increased percentage of CD4+ effector memory cells in comparison with naïve Balb/c mice immunized with rSm29. On the other hand, although immunization with Sm22.6 induced a robust immune response, it failed to induce protection. CONCLUSION/SIGNIFICANCE: Our results demonstrate that rSm29 retains its ability to induce protection in previously infected animals, reinforcing its potential as a vaccine candidate.

Secondary immune response of rainbow trout following repeated immersion vaccination

DEFF Research Database (Denmark)

Jaafar, R. M.; Al-Jubury, A.; Chettri, J. K.

2017-01-01

Teleosts are able to raise a protective immune response, comprising both innate and adaptive elements, against various pathogens. This is the basis for a widespread use of vaccines, administered as injection or immersion, in the aquaculture industry. It has been described that repeated injection...... vaccination of fish raises a secondary immune response, consisting of rapid, accelerated and increased antibody reaction. This study reports how rainbow trout responds to repeated immersion vaccination against yersiniosis (ERM) caused by the bacterial pathogen Yersinia ruckeri. It was found that rainbow trout...... does not raise a classical secondary response following repeated immersion vaccination. Serum antibody titres were merely slightly increased even after three immunizations, using 30-s immersion into a bacterin consisting of formalin-inactivated Y. ruckeri (serotype O1, biotypes 1 and 2), performed over...

Secondary immune response of rainbow trout following repeated immersion vaccination

DEFF Research Database (Denmark)

Jaafar, R. M.; Al-Jubury, Azmi; Chettri, Jiwan Kumar

2018-01-01

Teleosts are able to raise a protective immune response, comprising both innate and adaptive elements, against various pathogens. This is the basis for a widespread use of vaccines, administered as injection or immersion, in the aquaculture industry. It has been described that repeated injection...... vaccination of fish raises a secondary immune response, consisting of rapid, accelerated and increased antibody reaction. This study reports how rainbow trout responds to repeated immersion vaccination against yersiniosis (ERM) caused by the bacterial pathogen Yersinia ruckeri. It was found that rainbow trout...... does not raise a classical secondary response following repeated immersion vaccination. Serum antibody titres were merely slightly increased even after three immunizations, using 30-s immersion into a bacterin consisting of formalin-inactivated Y. ruckeri (serotype O1, biotypes 1 and 2), performed over...

Cannabinoid Receptor 2 (CB2 Plays a Role in the Generation of Germinal Center and Memory B Cells, but Not in the Production of Antigen-Specific IgG and IgM, in Response to T-dependent Antigens.

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Sreemanti Basu

Full Text Available The cannabinoid receptor 2 (CB2 has been reported to modulate B cell functions including migration, proliferation and isotype class switching. Since these processes are required for the generation of the germinal center (GC and antigen-specific plasma and memory cells following immunization with a T-dependent antigen, CB2 has the capacity to alter the quality and magnitude of T-dependent immune responses. To address this question, we immunized WT and CB2(-/- mice with the T-dependent antigen 4-hydroxy-3-nitrophenylacetyl (NP-chicken-gamma-globulin (CGG and measured GC B cell formation and the generation of antigen-specific B cells and serum immunoglobulin (Ig. While there was a significant reduction in the number of splenic GC B cells in CB2(-/- mice early in the response there was no detectable difference in the number of NP-specific IgM and IgG1 plasma cells. There was also no difference in NP-specific IgM and class switched IgG1 in the serum. In addition, we found no defect in the homing of plasma cells to the bone marrow (BM and affinity maturation, although memory B cell cells in the spleen were reduced in CB2(-/- mice. CB2-deficient mice also generated similar levels of antigen-specific IgM and IgG in the serum as WT following immunization with sheep red blood cells (sRBC. This study demonstrates that although CB2 plays a role in promoting GC and memory B cell formation/maintenance in the spleen, it is dispensable on all immune cell types required for the generation of antigen-specific IgM and IgG in T-dependent immune responses.

[Comparison of immune response after oral and intranasal immunization with recombinant Lactobacillus casei expressing ETEC F41].

Science.gov (United States)

Liu, Jiankui; Wei, Chunhua; Hou, Xilin; Wang, Guihua; Yu, Liyun

2009-04-01

In order to represent a promising strategy for mucosal vaccination, oral or intranasal immunization of Specific Pathogen Free (SPF) BALB/c mice were performed. The mucosal immunity, systemic immune and protective immune responses were compared after immunization with the recombinant Lactobacillus casei (L. casei) harboring enterotoxigenic Escherichia coli (ETEC) F41. The recombinant fusion proteins were detected by Western blot. Surface localization of the fusion protein was verified by immunofluorescence microscopy and flow cytometry. Six-week-old female SPF BALB/c mice (160 heads) were divided into 4 groups for immunization and control. Oral and intranasal immunization of mice was performed with the recombinant strain L. casei harboring pLA-F41 or pLA. For oral immunization, the mice were inoculated daily on days 0 to 4, 7 to 11, 21 to 25, and 49 to 53. A lighter schedule was used for nasal immunization (days 0 to 2, 7 to 9, 21 and 49). Specific anti-F41 IgG antibody in the serum and specific anti-F41 secret immunoglobulin A (sIgA) antibody in the lung, intestines, vagina fluid and feces of mice were detected by indirect ELISA. The mice orally or intranasally immunized with pLA-F41/L. casei and pLA/IL. casei were challenged with standard-type ETEC F41 (C83919) (2 x 10(3) LD50). Mice immunized with pLA-F41/L. casei could produce remarkable anti-F41 antibody level. More than 90% survived in oral immunization group whereas more than 85% survived in intranasal immunization group after challenged with C83919, all dead in the control group. Ninety percent of the pups survived in oral immunization group whereas 80% survived in intranasal immunization group after challenged with C83919, but only a 5% survival rate for pups that were either immunized with a control pLA vector or unimmunized. Oral or intranasal immunization with recombinant L. casei displaying ETEC F41 antigens on the surface induced effective and similar systemic and mucosal immune responses against the

Induction of the immune response suppression in mice inoculated with Candida albicans.

Science.gov (United States)

Valdez, J C; Mesón, D E; Sirena, A; de Petrino, S F; Eugenia, M; de Jorrat, B B; de Valdex, M G

1986-03-01

There is a controversy in respect to the immunological response (humoral or cellular) concerning the defense against Candida albicans. Candidosis would induce sub-populations of suppressor cells in the host cell-immune response. This report tries to show the effect of different doses of C. albicans (alive or heat-killed) on the expression of cell-mediated and humoral immunity. The effect upon cell immunity was determined by inoculating different lots of singeneic mice, doses of varied concentration of C. albicans and checking for delayed-type hipersensitivity (D.T.H.). D.T.H. was also controlled in syngeneic normal mice which had previously been injected with inoculated mice spleen cells. Humoral immunity was assayed by measuring the induced blastogenesis by Pokeweed Mitogen on spleen mononuclear cells with different doses of C. albicans. Results obtained show that the different doses gave origin to: Suppression of humoral and cell response (10(8) alive); Suppression of only humoral response (10(6) alive); Suppression of cell response and increase of humoral response (10(9) dead); Increase of both responses (10(8) dead).

Memory, verbal fluency, and response inhibition in normal aging

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Gaurav Thapliyal

2016-01-01

Full Text Available Background: The concepts of aging-related cognitive changes have appeared to be a major challenge in the society. In this context, the present study was planned to find out the functioning of aging population on different neurocognitive measures. Aims: The aim of the study was to find out the neurocognitive functioning, namely memory, verbal fluency, and response inhibition of normal aging population. Materials and Methods: Following purposive sampling technique, a total of 50 healthy subjects (30 males and 20 females in the age range of 60-70 years were recruited from Jaipur city of Rajasthan. Mini-mental state Examination, PGI memory scale, animal names test, and Stroop test were administered. Results: The findings reveal dysfunction in almost all the domains of memory, namely mental balance, attention and concentration, delayed recall, verbal retention for dissimilar pairs, visual retention and recognition, immediate recall, verbal retention for similar pairs, and visual retention. In domain of verbal fluency, all subjects gave low responses on the animal names test. In domain of response inhibition, all the subjects took less time in color test as compared to color word test on the Stroop task. Conclusions: Findings suggest that there are dysfunction in the area of memory, verbal fluency, and response inhibition in persons aged 60-70 years. However, recent and remote memory were found to be intact.

The immortality of humoral immunity.

Science.gov (United States)

Elgueta, Raul; de Vries, Victor C; Noelle, Randolph J

2010-07-01

Decades of high-titered antibody are sustained due to the persistence of memory B cells and long-lived plasma cells (PCs). The differentiation of each of these subsets is antigen- and T-cell driven and is dependent on signals acquired and integrated during the germinal center response. Inherent in the primary immune response must be the delivery of signals to B cells to create these populations, which have virtual immortality. Differences in biology and chemotactic behavior disperse memory B cells and long-lived PCs to a spectrum of anatomic sites. Each subset must rely on survival factors that can support their longevity. This review focuses on the generation of each of these subsets, their survival, and renewal, which must occur to sustain serological memory. In this context, we discuss the role of antigen, bystander inflammation, and cellular niches. The contribution of BAFF (B-cell activating factor belonging to the tumor necrosis factor family) and APRIL (a proliferation-inducing ligand) to the persistence of memory B cells and PCs are also detailed. Insights that have been provided over the past few years in the regulation of long-lived B-cell responses will have profound impact on vaccine development, the treatment of pre-sensitized patients for organ transplantation, and therapeutic interventions in both antibody- and T-cell-mediated autoimmunity.

Protein energy malnutrition impairs homeostatic proliferation of memory CD8 T cells.

Science.gov (United States)

Iyer, Smita S; Chatraw, Janel Hart; Tan, Wendy G; Wherry, E John; Becker, Todd C; Ahmed, Rafi; Kapasi, Zoher F

2012-01-01

Nutrition is a critical but poorly understood determinant of immunity. There is abundant epidemiological evidence linking protein malnutrition to impaired vaccine efficacy and increased susceptibility to infections; yet, the role of dietary protein in immune memory homeostasis remains poorly understood. In this study, we show that protein-energy malnutrition induced in mice by low-protein (LP) feeding has a detrimental impact on CD8 memory. Relative to adequate protein (AP)-fed controls, LP feeding in lymphocytic choriomeningitis virus (LCMV)-immune mice resulted in a 2-fold decrease in LCMV-specific CD8 memory T cells. Adoptive transfer of memory cells, labeled with a division tracking dye, from AP mice into naive LP or AP mice demonstrated that protein-energy malnutrition caused profound defects in homeostatic proliferation. Remarkably, this defect occurred despite the lymphopenic environment in LP hosts. Whereas Ag-specific memory cells in LP and AP hosts were phenotypically similar, memory cells in LP hosts were markedly less responsive to polyinosinic-polycytidylic acid-induced acute proliferative signals. Furthermore, upon recall, memory cells in LP hosts displayed reduced proliferation and protection from challenge with LCMV-clone 13, resulting in impaired viral clearance in the liver. The findings show a metabolic requirement of dietary protein in sustaining functional CD8 memory and suggest that interventions to optimize dietary protein intake may improve vaccine efficacy in malnourished individuals.

Persistent Low-Level Replication of SIVΔnef Drives Maturation of Antibody and CD8 T Cell Responses to Induce Protective Immunity against Vaginal SIV Infection.

Science.gov (United States)

Adnan, Sama; Reeves, R Keith; Gillis, Jacqueline; Wong, Fay E; Yu, Yi; Camp, Jeremy V; Li, Qingsheng; Connole, Michelle; Li, Yuan; Piatak, Michael; Lifson, Jeffrey D; Li, Wenjun; Keele, Brandon F; Kozlowski, Pamela A; Desrosiers, Ronald C; Haase, Ashley T; Johnson, R Paul

2016-12-01

Defining the correlates of immune protection conferred by SIVΔnef, the most effective vaccine against SIV challenge, could enable the design of a protective vaccine against HIV infection. Here we provide a comprehensive assessment of immune responses that protect against SIV infection through detailed analyses of cellular and humoral immune responses in the blood and tissues of rhesus macaques vaccinated with SIVΔnef and then vaginally challenged with wild-type SIV. Despite the presence of robust cellular immune responses, animals at 5 weeks after vaccination displayed only transient viral suppression of challenge virus, whereas all macaques challenged at weeks 20 and 40 post-SIVΔnef vaccination were protected, as defined by either apparent sterile protection or significant suppression of viremia in infected animals. Multiple parameters of CD8 T cell function temporally correlated with maturation of protection, including polyfunctionality, phenotypic differentiation, and redistribution to gut and lymphoid tissues. Importantly, we also demonstrate the induction of a tissue-resident memory population of SIV-specific CD8 T cells in the vaginal mucosa, which was dependent on ongoing low-level antigenic stimulation. Moreover, we show that vaginal and serum antibody titers inversely correlated with post-challenge peak viral load, and we correlate the accumulation and affinity maturation of the antibody response to the duration of the vaccination period as well as to the SIVΔnef antigenic load. In conclusion, maturation of SIVΔnef-induced CD8 T cell and antibody responses, both propelled by viral persistence in the gut mucosa and secondary lymphoid tissues, results in protective immune responses that are able to interrupt viral transmission at mucosal portals of entry as well as potential sites of viral dissemination.

Vaxfectin enhances antigen specific antibody titers and maintains Th1 type immune responses to plasmid DNA immunization.

Science.gov (United States)

Reyes, L; Hartikka, J; Bozoukova, V; Sukhu, L; Nishioka, W; Singh, G; Ferrari, M; Enas, J; Wheeler, C J; Manthorpe, M; Wloch, M K

2001-06-14

Antigen specific immune responses were characterized after intramuscular immunization of BALB/c mice with 5 antigen encoding plasmid DNAs (pDNAs) complexed with Vaxfectin, a cationic lipid formulation. Vaxfectin increased IgG titers for all of the antigens with no effect on the CTL responses to the 2 antigens for which CTL assays were performed. Both antigen specific IgG1 and IgG2a were increased, although IgG2a remained greater than IgG1. Furthermore, Vaxfectin had no effect on IFN-gamma or IL-4 production by splenocytes re-stimulated with antigen, suggesting that the Th1 type responses typical of intramuscular pDNA immunization were not altered. Studies with IL-6 -/- mice suggest that the antibody enhancement is IL-6 dependent and results in a correlative increase in antigen specific antibody secreting cells.

Dermatology in the Darwin anniversary. Part 2: Evolution of the skin-associated immune system.

Science.gov (United States)

Wölfle, Ute; Martin, Stefan; Emde, Matthias; Schempp, Christoph

2009-10-01

The present review highlights the evolution of the skin-associated immune system from the invertebrates to the vertebrates and man. In the invertebrates a non-specific humoral immune response dominates. It includes antimicrobial peptides, oxidases, lysozyme, agglutinins, coagulins and melanin. The cellular immune system initially consists of undifferentiated mesenchymal stem cells. Later migrating phagocytes and natural killer cells occur. From the fishes on, dendritic cells are present, linking innate and adaptive immune responses. In addition to this unspecific but highly effective immune system, the specific immune response, based on genetic recombination, is present in the vertebrates starting with the chondral fishes. The adaptive immune system possesses unlimited numbers of highly specific antibodies and T-cell receptors, increasingly tissue specific MHC restriction, and cellular memory. Elements of the skin-associated adaptive immune system are first detectable in the teleost fishes in the form of intraepithelial IgM positive lymphocytes and dendritic cells. Moving up to mammals and man, the skin-associated immune system became more and more complex and effective.

Innate immune responses to gut microbiota differ between oceanic and freshwater threespine stickleback populations

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Kathryn Milligan-Myhre

2016-02-01

Full Text Available Animal hosts must co-exist with beneficial microbes while simultaneously being able to mount rapid, non-specific, innate immune responses to pathogenic microbes. How this balance is achieved is not fully understood, and disruption of this relationship can lead to disease. Excessive inflammatory responses to resident microbes are characteristic of certain gastrointestinal pathologies such as inflammatory bowel disease (IBD. The immune dysregulation of IBD has complex genetic underpinnings that cannot be fully recapitulated with single-gene-knockout models. A deeper understanding of the genetic regulation of innate immune responses to resident microbes requires the ability to measure immune responses in the presence and absence of the microbiota using vertebrate models with complex genetic variation. Here, we describe a new gnotobiotic vertebrate model to explore the natural genetic variation that contributes to differences in innate immune responses to microbiota. Threespine stickleback, Gasterosteus aculeatus, has been used to study the developmental genetics of complex traits during the repeated evolution from ancestral oceanic to derived freshwater forms. We established methods to rear germ-free stickleback larvae and gnotobiotic animals monoassociated with single bacterial isolates. We characterized the innate immune response of these fish to resident gut microbes by quantifying the neutrophil cells in conventionally reared monoassociated or germ-free stickleback from both oceanic and freshwater populations grown in a common intermediate salinity environment. We found that oceanic and freshwater fish in the wild and in the laboratory share many intestinal microbial community members. However, oceanic fish mount a strong immune response to residential microbiota, whereas freshwater fish frequently do not. A strong innate immune response was uniformly observed across oceanic families, but this response varied among families of freshwater fish

Inhibition of the immune response to experimental fresh osteoarticular allografts

International Nuclear Information System (INIS)

Rodrigo, J.J.; Schnaser, A.M.; Reynolds, H.M. Jr.; Biggart, J.M. III; Leathers, M.W.; Chism, S.E.; Thorson, E.; Grotz, T.; Yang, Q.M.

1989-01-01

The immune response to osteoarticular allografts is capable of destroying the cartilage--a tissue that has antigens on its cells identical to those on the bone and marrow cells. Osteoarticular allografts of the distal femur were performed in rats using various methods to attempt to temporarily inhibit the antibody response. The temporary systemic immunosuppressant regimens investigated were cyclophosphamide, azathioprine and prednisolone, cyclosporine A, and total lymphoid irradiation. The most successful appeared to be cyclosporine A, but significant side effects were observed. To specifically inhibit the immune response in the allograft antigens without systemically inhibiting the entire immune system, passive enhancement and preadministration of donor blood were tried. Neither was as effective as coating the donor bone with biodegradable cements, a method previously found to be successful. Cyclosporine A was investigated in dogs in a preliminary study of medial compartmental knee allografts and was found to be successful in inhibiting the antibody response and in producing a more successful graft; however, some significant side effects were similarly observed

Suppression of Long-Lived Humoral Immunity Following Borrelia burgdorferi Infection.

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Rebecca A Elsner

2015-07-01

Full Text Available Lyme Disease caused by infection with Borrelia burgdorferi is an emerging infectious disease and already by far the most common vector-borne disease in the U.S. Similar to many other infections, infection with B. burgdorferi results in strong antibody response induction, which can be used clinically as a diagnostic measure of prior exposure. However, clinical studies have shown a sometimes-precipitous decline of such antibodies shortly following antibiotic treatment, revealing a potential deficit in the host's ability to induce and/or maintain long-term protective antibodies. This is further supported by reports of frequent repeat infections with B. burgdorferi in endemic areas. The mechanisms underlying such a lack of long-term humoral immunity, however, remain unknown. We show here that B. burgdorferi infected mice show a similar rapid disappearance of Borrelia-specific antibodies after infection and subsequent antibiotic treatment. This failure was associated with development of only short-lived germinal centers, micro-anatomical locations from which long-lived immunity originates. These showed structural abnormalities and failed to induce memory B cells and long-lived plasma cells for months after the infection, rendering the mice susceptible to reinfection with the same strain of B. burgdorferi. The inability to induce long-lived immune responses was not due to the particular nature of the immunogenic antigens of B. burgdorferi, as antibodies to both T-dependent and T-independent Borrelia antigens lacked longevity and B cell memory induction. Furthermore, influenza immunization administered at the time of Borrelia infection also failed to induce robust antibody responses, dramatically reducing the protective antiviral capacity of the humoral response. Collectively, these studies show that B. burgdorferi-infection results in targeted and temporary immunosuppression of the host and bring new insight into the mechanisms underlying the failure

A new theory of cytotoxic T-lymphocyte memory: implications for HIV treatment

DEFF Research Database (Denmark)

Wodarz, D; Page, K M; Arnaout, R A

2000-01-01

result in the failure to establish CTL memory which in turn leads to viral persistence. Based on our models we suggest conceptual treatment regimes which ensure establishment of CTL memory. This would allow the immune response to control HIV in the long term in the absence of continued therapy....... reinfection is only effective in a restricted set of circumstances, we find that resolution of the primary infection requires persistence of CTL precursors (GTLp), as well as a fast rate of activation of the CTLp. Since these are commonly the defining characteristics of CTL memory, we propose that CTL memory...... may have evolved in order to clear the virus during primary challenge. We show experimental data from lymphocytic choriomeningitis virus infection in mice, supporting our theory on CTL memory. We adapt our models to HIV and find that immune impairment during the primary phase of the infection may...

Dendritic cells in dengue virus infection: Targets of virus replication and mediators of immunity

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Michael A. Schmid

2014-12-01

Full Text Available Dendritic cells (DCs are sentinels of the immune system and detect pathogens at sites of entry, such as the skin. In addition to the ability of DCs to control infections directly via their innate immune functions, DCs help to prime adaptive B and T cell responses via antigen presentation in lymphoid tissues. Infected Aedes aegypti or Ae. albopictus mosquitoes transmit the four dengue virus (DENV serotypes to humans while probing for small blood vessels in the skin. DENV causes the most prevalent arthropod-borne viral disease in humans, yet no vaccine or specific therapeutic is currently approved. Although primary DENV infection confers life-long protective immunity against re-infection with the same DENV serotype, secondary infection with a different DENV serotype can lead to increased disease severity via cross-reactive T cells or enhancing antibodies. This review summarizes recent findings in humans and animal models about DENV infection of DCs, monocytes and macrophages. We discuss the dual role of DCs as both targets of DENV replication and mediators of innate and adaptive immunity, and summarize immune evasion strategies whereby DENV impairs the function of infected DCs. We suggest that DCs play a key role in priming DENV-specific neutralizing or potentially harmful memory B and T cell responses, and that future DC-directed therapies may help induce protective memory responses and reduce dengue pathogenesis.

Transdermal influenza immunization with vaccine-coated microneedle arrays.

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