Immune Response In Individuals Research Articles

Individuals with inherited chromosomally integrated human herpes virus 6 (ciHHV-6) have functionally active HHV-6 specific T-cell immunity

To evaluate the human herpes virus 6 (HHV-6) -specific immune response in individuals with chromosomally integrated HHV-6 (ciHHV-6), we measured HHV-6-antigen-specific cytokine responses (interferon-γ, interleukin-2, tumour necrosis factor-α) in T cells by flow cytometry in 12 and 16 individuals with and without ciHHV-6, respectively. All individuals with ciHHV-6 showed HHV-6-specific T cells with higher frequencies of HHV-6-specific CD8+ cells (0.03–14.93, median 2.15% of CD8+ cells) compared with non-ciHHV-6 (0.0–10.67, median 0.36%, p 0.026). The observed increased HHV-6-specific functionally active responses in individuals with ciHHV-6 clearly disprove speculations on immune tolerance in ciHHV-6 and indicate clinical and immunological implications of ciHHV-6.

Associations between hepcidin and immune response in individuals with hyperbilirubinaemia and severe malaria due to Plasmodium vivax infection.

BackgroundHyperbilirubinaemia (bilirubin >51.3 μmol/L) alone is not indicative of severe malaria, and the immune response underlying hyperbilirubinaemia remains largely unexplored. Liver damage associated with hyperbilirubinaemia may alter the expression of hepcidin, which regulates systemic iron by degrading ferroportin. For this study, the association between hepcidin and the levels of cytokines and chemokines in the serum of individuals with mild and severe vivax malaria and subjects with malaria with isolated hyperbilirubinaemia was evaluated.MethodsCytokines/chemokines and hepcidin were measured in individuals with mild (n = 72) and severe (n = 17) vivax malaria, as well as in the serum of subjects with vivax malaria with isolated hyperbilirubinaemia (n = 14) from the Brazilian Amazon between 2009 and 2013 by multiplex assay and ELISA, respectively. The polymorphism 744 G > T in the ferroportin gene was identified by restriction fragment-length polymorphism analysis and the restriction enzyme PvuII.ResultsThe polymorphism at position 744 G > T in the ferroportin gene was typed and no differences in the distributions of genotypes or alleles were observed between the study groups. Subjects with severe malaria had higher levels of interleukin (IL)-2 and IL-13 than subjects with hyperbilirubinaemia. No differences in the expression of immune markers were observed between subjects with mild malaria and those with hyperbilirubinaemia. However, hepcidin levels were higher in individuals with severe malaria and hyperbilirubinaemia than those with mild malaria (p = 0.0002 and p = 0.0004, respectively) and cut-off values of hepcidin differentiated these groups from subjects with mild malaria. Hepcidin was positively associated with IL-6 and IL-10 levels and with parasitaemia in subjects with mild malaria and with IFN-γ in subjects with severe malaria.ConclusionsMalaria in the presence of hyperbilirubinaemia produces a less robust inflammatory response compared to severe cases of malaria. Hepcidin levels are positively associated with immune markers in vivax malaria outcomes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12936-015-0930-x) contains supplementary material, which is available to authorized users.

Impact of Fighting on Antibody Response to Hepatitis B Virus Vaccine in Mice.

Antibody responses to vaccines can be influenced by various behavioral and psychosocial factors. Few reports exist on the impact of fighting on antibody response to vaccines. This study unexpectedly found that fighting could significantly enhance antibody production in male mice immunized with hepatitis B virus (HBV) vaccines. To confirm the finding, a mouse-fighting model was established in which it was observed that only intense fighting, not mild fighting, enhanced the antibody response to HBV surface antigen in male mice, and that the frequency of fighting and active attacks during fighting showed no obvious relationship with the antibody levels in the male mice that experienced fighting. In addition, fighting can cause significant upregulation of CD80 in CD11c(+) cells in the spleen of male mice. These data suggest that fighting could influence the humoral immune response in individuals immunized with vaccines or infected with microbes.

Similar protective immunity induced by an inactivated enterovirus 71 (EV71) vaccine in neonatal rhesus macaques and children

During the development of enterovirus 71 (EV71) inactivated vaccine for preventing human hand, foot and mouth diseases (HFMD) by EV71 infection, an effective animal model is presumed to be significant and necessary. Our previous study demonstrated that the vesicles in oral regions and limbs potentially associated with viremia, which are the typical manifestations of HFMD, and remarkable pathologic changes were identified in various tissues of neonatal rhesus macaque during EV71 infection. Although an immune response in terms of neutralizing antibody and T cell memory was observed in animals infected by the virus or stimulated by viral antigen, whether such a response could be considered as an indicator to justify the immune response in individuals vaccinated or infected in a pandemic needs to be investigated. Here, a comparative analysis of the neutralizing antibody response and IFN-γ-specific T cell response in vaccinated neonatal rhesus macaques and a human clinical trial with an EV71 inactivated vaccine was performed, and the results showed the identical tendency and increased level of neutralizing antibody and the IFN-γ-specific T cell response stimulated by the EV71 antigen peptide. Importantly, the clinical protective efficacy against virus infection by the elicited immune response in the immunized population compared with the placebo control and the up-modulated gene profile associated with immune activation were similar to those in infected macaques. Further safety verification of this vaccine in neonatal rhesus macaques and children confirmed the potential use of the macaque as a reliable model for the evaluation of an EV71 candidate vaccine.

Long-Term Immunogenicity and Safety of a Conventional Influenza Vaccine in Patients with Type 2 Diabetes.

No previous studies have assessed the persistence of immune responses in individuals with diabetes. We conducted this study to evaluate the long-term immunogenicity and safety of an influenza vaccine in type 2 diabetic subjects compared with nondiabetic controls. A randomized and controlled study was conducted at two university hospitals during the 2012-2013 influenza season. The study vaccine was a standard-dose trivalent subunit inactivated intramuscular vaccine. Serum hemagglutination-inhibiting (HI) antibodies were measured at the time of vaccination and 1 month and 6 months after vaccination. Local and systemic reactions were recorded for 7 days. A total of 105 diabetic patients and 108 controls were included in the analysis. One month after vaccination, both the diabetic and nondiabetic groups satisfied all of the criteria of the Committee for Medical Products for Human Use (CHMP), and the immunogenicity profiles were statistically similar between the two groups. Although the vaccine was well tolerated, and all adverse reactions were mild to moderate, there was a tendency toward a reduced incidence of local reactions in the diabetic group. All values in the long-term immunogenicity profiles were statistically similar between the two groups, except for the seroprotection rate for the A/H1N1 influenza virus strain, which was significantly lower in the elderly diabetic group than that in the elderly nondiabetic group. However, in multivariate analysis, long-term immunogenicity was associated with age and prevaccination titer, regardless of diabetes status. (This study has been registered at CRIS [https://cris.nih.go.kr/cris/en/] under registration no. KCT0001423.).

Antibodies to post-translationally modified insulin in type 1 diabetes.

Insulin is the most specific beta cell antigen and a potential primary autoantigen in type 1 diabetes. Insulin autoantibodies (IAAs) are the earliest marker of beta cell autoimmunity; however, only slightly more than 50% of children and even fewer adults newly diagnosed with type 1 diabetes are IAA positive. The aim of this investigation was to determine if oxidative post-translational modification (oxPTM) of insulin by reactive oxidants associated with islet inflammation generates neoepitopes that stimulate an immune response in individuals with type 1 diabetes. oxPTM of insulin was generated using ribose and various reactive oxygen species. Modifications were analysed by SDS-PAGE, three-dimensional fluorescence and MS. Autoreactivity to oxPTM insulin (oxPTM-INS) was observed by ELISA and western blotting, using sera from participants with type 1 or type 2 diabetes and healthy controls as probes. IAA was measured using the gold-standard radiobinding assay (RBA). MS of oxPTM-INS identified chlorination of Tyr16 and Tyr26; oxidation of His5, Cys7 and Phe24; and glycation of Lys29 and Phe1 in chain B. Significantly higher binding to oxPTM-INS vs native insulin was observed in participants with type 1 diabetes, with 84% sensitivity compared with 61% sensitivity for RBA. oxPTM-INS autoantibodies and IAA co-existed in 50% of those with type 1 diabetes. Importantly 34% of those with diabetes who were IAA negative were oxPTM-INS positive. Altogether, 95% of participants with type 1 diabetes presented with autoimmunity to insulin by RBA, oxPTM-INS or both. Binding to oxPTM-INS was directed towards oxPTM-INS fragments with slower mobility than native insulin. These data suggest that oxPTM-INS is a potential autoantigen in individuals with new-onset type 1 diabetes.

INVESTIGAÇÃO DO TRATAMENTO COM O BENZONIDAZOL SOBRE A RESPOSTA IMUNOLÓGICA DE PORTADORES CRÔNICOS DA DOENÇA DE CHAGAS

Evidence suggests that benznidazole treatment directly interferes withthe host immune response in the chronic phase of Chagas disease. However,a longitudinal study to simultaneously evaluate immune parameters related toactivation, cytotoxicity, cell regulation and inflammation of these chronic patientssubmitted to etiological treatment has never been performed. Therefore, the presentstudy aimed to evaluate immune response in individuals with chronic Chagasdisease before and after benznidazole treatment. Twenty-one adults classifiedas in the chronic phase of Chagas disease (indeterminate form-IND=13/cardiacform-CARD=8) were selected. Blood samples were collected before etiologicaltreatment (T0/n=21), after 2-3 months (T1/n=21) and after 5-6 months (T2/n=16),which were analyzed by flow cytometry. Increase in CD5+CD19+ B1 lymphocytes,as well as greater activation of cytotoxic T CD8+ cells (CD28+), indicated thatbenznidazole exacerbates cellular mechanisms related to Trypanosoma cruzielimination. On the other hand, there was a reduction in IFN-g production by T and Blymphocytes in all individuals. These phenomena associated with a low percentageof CD4+CD25+/highFoxP3+ T lymphocytes, suggest a loss of the mechanismsagainst the parasite and to control inflammatory response. It was emphasized thatthe rise of a modulated Th1 cytokine pattern (inflammatory: IFN-g / regulatory:IL-4, IL-6, IL-10) delayed (T2) in the IND+CARD group may indicate that after aninitial immune imbalance, host response would become immunomodulatory. Thus,benznidazole acts by unbalancing different mechanisms related to immune responsein chronic Chagas disease. A long follow-up investigation will be necessary toconclude if these phenomena are definitive or are due to high levels of drug andantigen in the host organism.

Exposure to Δ9-Tetrahydrocannabinol Impairs the Differentiation of Human Monocyte-derived Dendritic Cells and their Capacity for T cell Activation.

The capacity for human monocytes to differentiate into antigen-presenting dendritic cells (DC) can be influenced by a number of immune modulating signals. Monocytes express intracellular cannabinoid type 1 (CB1) and 2 (CB2) receptors and we demonstrate that exposure to Δ9-tetrahydrocannabinol (THC) inhibits the forskolin-induced generation of cyclic adenosine monophosphate in a CB2-specific manner. In order to examine the potential impact of cannabinoids on the generation of monocyte-derived DC, monocytes were cultured in vitro with differentiation medium alone [containing granulocyte/macrophage-colony stimulating factor (GM-CSF) and Interleukin-4 (IL-4)] or in combination with THC. The presence of THC (0.25-1.0μg/ml) altered key features of DC differentiation, producing a concentration-dependent decrease in surface expression of CD11c, HLA-DR and costimulatory molecules (CD40 and CD86), less effective antigen uptake, and signs of functional skewing with decreased production of IL-12 but normal levels of IL-10. When examined in a mixed leukocyte reaction, DC that had been generated in the presence of THC were poor T cell activators as evidenced by their inability to generate effector/memory T cells or to stimulate robust IFN-γ responses. Some of these effects were partially restored by exposure to exogenous IL-7 and bacterial superantigen (S. aureus Cowans strain). These studies demonstrate that human monocytes express functional cannabinoid receptors and suggest that exposure to THC can alter their differentiation into functional antigen presenting cells; an effect that may be counter-balanced by the presence of other immunoregulatory factors. The impact of cannabinoids on adaptive immune responses in individuals with frequent drug exposure remains to be determined.

IgG response to different stage-specific antigens of Mycobacterium tuberculosis

IgG response to different stage-specific antigens of Mycobacterium tuberculosis

Immunoregulation in human American leishmaniasis: balancing pathology and protection

Leishmaniasis covers a broad spectrum of diseases with distinct, and sometimes overlapping, characteristics. The common thread in all forms of leishmaniasis is the infection by the parasite Leishmania belonging to the genus Leishmania. Upon infection of humans, there can be at least three outcomes, (i) control of Leishmania by the host immune response resulting in asymptomatic disease, (ii) patent infection and development of a relatively mild form of leishmaniasis and (iii) patent infection and development of severe clinical forms. The factors that determine the outcome of an initial inoculation with Leishmania are many, with the species of Leishmania representing one of the strongest predictive factors for the development of a given clinical form of disease. This is seen with L. braziliensis and L. amazonensis, infection leading mostly to tegumentary forms of disease, and L. infantum with the potential to induce visceral disease. However, it is also clear that the host immune response is a key factor in disease progression, not only responsible for control of Leishmania, but also playing an important role in disease progression and pathology. This duality between protective and pathogenic immune responses in individuals infected with Leishmania in the Americas is the focus of this review.

Role of neutrophil extracellular traps following injury.

Neutrophil extracellular traps (NETs), which consist of neutrophil DNA and cytoplasmic proteins, have been shown to be involved in various infectious, inflammatory, and autoimmune diseases. Neutrophil extracellular traps are abundant at the site of infection and acute inflammation. Neutrophil extracellular trap formation can occur through various intracellular signaling pathways, including peptidylarginine deiminase 4, Raf-MEK-ERK, nitric oxide, Toll-like receptor 4, high mobility group box 1, pentraxin 3, and mammalian targets of rapamycin. A growing body of evidence indicates that NETs may play an important role in injury, and decreases in NETs could reduce tissue injury. Neutrophil extracellular traps are believed to modulate the inflammatory and immune responses of individuals after injury. In this review, the role of NETs in injury, including traumatic injury, ischemia-reperfusion-induced injury, and sepsis, as well as the potential markers and therapeutic targets of NET-related injury will be discussed.

Deciphering and correcting impaired respiratory virus-specific immunity caused by vitamin A deficiency (VIR2P.1017)

Abstract Vitamin A deficiency (VAD) is a leading contributor to pediatric morbidity and mortality worldwide. Recently we have shown that VAD in mice impairs mucosal IgA responses in the upper respiratory tract during both paramyxovirus and influenza virus vaccination, thus impeding a first defense against these pathogens at their point of entry. The key vitamin A metabolite responsible for normal immune function is retinoic acid (RA). Previously, RA was believed to be produced predominantly by gut dendritic cells expressing aldehyde dehydrogenase (ALDH1A), an enzyme required for metabolism of RA from RA precursors. However, we found that epithelial cells of the respiratory tract autonomously produce ALDH1A. These cells also produce IL-6 and GM-CSF and can facilitate IgA production from activated splenocytes in vitro. Further in vitro analyses demonstrated that outcomes of vitamin A supplementation were affected by a variety of factors including concentration and type of vitamin A metabolite, as well as cells targeted. Based on these results, we supplemented a respiratory virus vaccine with a single intranasal dose of retinol, retinyl palmitate, or a combination of IL-6 and GM-CSF in VAD mice, and observed enhanced virus-specific mucosal IgA. In total, our data provide insight into the role of vitamin A in virus-specific immunity, while defining feasible methods for the correction of impaired mucosal immune responses in individuals with VAD.

Decline in titers of anti-idiotypic antibodies specific to autoantibodies to GAD65 (GAD65Ab) precedes development of GAD65Ab and type 1 diabetes.

The humoral Idiotypic Network consisting of antibodies and their anti-idiotypic antibodies (anti-Id) can be temporarily upset by antigen exposure. In the healthy immune response the original equilibrium is eventually restored through counter-regulatory mechanisms. In certain autoimmune diseases however, autoantibody levels exceed those of their respective anti-Id, indicating a permanent disturbance in the respective humoral Idiotypic Network. We investigated anti-Id directed to a major Type 1 diabetes (T1D)-associated autoantibody (GAD65Ab) in two independent cohorts during progression to disease. Samples taken from participants of the Natural History Study showed significantly lower anti-Id levels in individuals that later progressed to T1D compared to non-progressors (anti-Id antibody index of 0.06 vs. 0.08, respectively, p = 0.02). We also observed a significant inverse correlation between anti-Id levels and age at sampling, but only in progressors (p = 0.014). Finally, anti-Id levels in progressors showed a significant decline during progression as compared to longitudinal anti-Id levels in non-progressors (median rate of change: −0.0004 vs. +0.0004, respectively, p = 0.003), suggesting a loss of anti-Id during progression. Our analysis of the Diabetes Prediction in Skåne cohort showed that early in life (age 2) individuals at risk have anti-Id levels indistinguishable from those in healthy controls, indicating that low anti-Id levels are not an innate characteristic of the immune response in individuals at risk. Notably, anti-Id levels declined significantly in individuals that later developed GAD65Ab suggesting that the decline in anti-Id levels precedes the emergence of GAD65Ab (median rate of change: −0.005) compared to matched controls (median rate of change: +0.001) (p = 0.0016). We conclude that while anti-Id are present early in life, their levels decrease prior to the appearance of GAD65Ab and to the development of T1D.

Evaluation of an artificial neural network to ascertain why there is a high incidence of hepatitis B in the Chinese population after vaccination

ObjectiveThe purpose of the study was to understand why there is a high incidence of hepatitis B, including acute and chronic infections, after vaccination. MethodsAll data were obtained from the published information. The incidence of hepatitis B, life expectancy, and positive rates of hepatitis B surface antigen (HBsAg) and the antibody to HBsAg (anti-HBs) in a specific observation year was depicted. The relationships between the HBsAg-positive rate, anti-HBs-positive rate, life expectancy and incidence of hepatitis B were assessed by Pearson’s correlation. The quantitative effects of HBsAg-positive rate, anti-HBs-positive rate and life expectancy on hepatitis B incidence were assessed by SPSS 18.0 software with a neural network. ResultsThere was no correlation between hepatitis B incidence and the rates of HBsAg or anti-HBs (r=−0.334 for HBsAg, r=0.247 for anti-HBs, p>0.05 for both indicators). A clear correlation was observed between incidence and life expectancy (r=0.841, p<0.05). The standardized percentage of affect of life expectancy on hepatitis B incidence (100%) was much higher than that of either the rates of HBsAg (59.0%) or anti-HBs (45.7%). ConclusionAn increase in life expectancy and an improved quality of life may be associated with a higher incidence of hepatitis B. Because hepatitis B is caused by the host immune response, a stronger immune response in individuals with an improved quality of life could contribute to that higher incidence.

Development of CD8+ T cells expressing two distinct receptors specific for MTB and HIV‐1 peptides

The immune response in individuals co-infected with Mycobacterium tuberculosis (MTB) and the human immunodeficiency virus (MTB/HIV) gradually deteriorates, particularly in the cellular compartment. Adoptive transfer of functional effector T cells can confer protective immunity to immunodeficient MTB/HIV co-infected recipients. However, few such effector T cells exist in vivo, and their isolation and amplification to sufficient numbers is difficult. Therefore, enhancing immune responses against both pathogens is critical for treating MTB/HIV co-infected patients. One approach is adoptive transfer of T cell receptor (TCR) gene-modified T cells for the treatment of MTB/HIV co-infections because lymphocyte numbers and their functional avidity is significantly increased by TCR gene transfer. To generate bispecific CD8+ T cells, MTB Ag85B199–207 peptide-specific TCRs (MTB/TCR) and HIV-1 Env120–128 peptide-specific TCRs (HIV/TCR) were isolated and introduced into CD8+ T cells simultaneously using a retroviral vector. To avoid mispairing among exogenous and endogenous TCRs, and to improve the function and stability of the introduced TCRs, several strategies were employed, including introducing mutations in the MTB/TCR constant (C) regions, substituting part of the HIV/TCR C regions with CD3ζ, and linking gene segments with three different 2A peptides. Results presented in this report suggest that the engineered T cells possessed peptide-specific specificity resulting in cytokine production and cytotoxic activity. This is the first report describing the generation of engineered T cells specific for two different pathogens and provides new insights into TCR gene therapy for the treatment of immunocompromised MTB/HIV co-infected patients.

Heterogeneity in antibody range and the antigenic drift of influenza A viruses

In this paper we explore the consequences of a heterogeneous immune response in individuals on the evolution of a rapidly mutating virus. We show that several features of the incidence and phylogenetic patterns typical of influenza A may be understood in this framework. In our model, limited diversity and rapid drift of the circulating viral strains result from the interplay of two interacting subpopulations with different types of immune response, narrow or broad, upon infection. The subpopulation with the narrow immune response acts as a reservoir where consecutive mutations escape immunity and can persist. Strains with a number of accumulated mutations escape immunity in the other subpopulation as well, causing larger epidemic peaks in the whole population, and reducing strain diversity. Overall, our model produces a modulation of epidemic peak heights and patterns of antigenic drift consistent with reported observations, suggesting an underlying mechanism for the evolutionary epidemiology of influenza, in particular, and other infectious diseases, more generally.

Sensory symptoms and immune response in individuals infected with HTLV-1

Sensory symptoms and immune response in individuals infected with HTLV-1

Wheat amylase trypsin inhibitors drive intestinal inflammation via activation of toll-like receptor 4

Ingestion of wheat, barley, or rye triggers small intestinal inflammation in patients with celiac disease. Specifically, the storage proteins of these cereals (gluten) elicit an adaptive Th1-mediated immune response in individuals carrying HLA-DQ2 or HLA-DQ8 as major genetic predisposition. This well-defined role of adaptive immunity contrasts with an ill-defined component of innate immunity in celiac disease. We identify the α-amylase/trypsin inhibitors (ATIs) CM3 and 0.19, pest resistance molecules in wheat, as strong activators of innate immune responses in monocytes, macrophages, and dendritic cells. ATIs engage the TLR4-MD2-CD14 complex and lead to up-regulation of maturation markers and elicit release of proinflammatory cytokines in cells from celiac and nonceliac patients and in celiac patients' biopsies. Mice deficient in TLR4 or TLR4 signaling are protected from intestinal and systemic immune responses upon oral challenge with ATIs. These findings define cereal ATIs as novel contributors to celiac disease. Moreover, ATIs may fuel inflammation and immune reactions in other intestinal and nonintestinal immune disorders.

Preservation HIV-1–Specific IFNγ+ CD4+ T-Cell Responses in Breakthrough Infections After Exposure to Tenofovir Gel in the CAPRISA 004 Microbicide Trial

The Centre for the AIDS Program of Research in South Africa 004 trial demonstrated reduction of sexual HIV-1 acquisition in women using a vaginal microbicide containing tenofovir. A better understanding of the consequences of antiretroviral-containing microbicides for immune responses in individuals with intercurrent HIV-1 infection is needed for future trials combining the use of microbicides with HIV-1 vaccines. Investigation of immune responses in women who acquired HIV-1 although using tenofovir gel showed significantly higher (P = 0.01) Gag-specific IFNγ+ CD4+ T-cell responses. The use of tenofovir-containing gel around the time of infection can modulate HIV-1 immunity, and these immunological changes need to be considered in future trials combining vaccines and microbicides.

The Immunological Footprint of Mycobacterium tuberculosis T-cell Epitope Recognition

Aerosols containing Mycobacterium tuberculosis (MTB) generated from the cough of patients with active pulmonary tuberculosis are the source of MTB infection. About 70% of individuals exposed to infected aerosols do not get infected, depending on the intensity and duration of MTB exposure. Only 40% of the rest of the individuals (about 10% of those originally exposed) develop primary tuberculosis, whereas the remaining 60% contain the infection with generation of a robust immune response leading to latent tuberculosis, which is regarded as a spectrum rather than a single entity. The mechanisms involved in this natural protection are not yet well understood. There is an increasing need to integrate all disparate observations into a coherent systems biology approach for a comprehensive understanding: we need to decipher the nature of success and failure in MTB infection in humans. New advances in cellular immunology will aid in achieving that goal. We review here the nature of MTB peptide generation, antigen presentation, and detection of major histocompatibility complex class I and II-presented T-cell epitopes. Cross-sectional thinking from lessons learned in the context of the major efforts to develop vaccines will help to dissect biologically relevant mechanisms that need to be translated into the clinical context of MTB infection with the aim to (1) better understand clinically relevant T-cell responses in individuals protected from tuberculosis disease and develop markers of immune protection and vaccine take, (2) characterize the nature of the immune response in individuals who are not able to contain MTB infection, and ultimately (3) characterize markers to gauge response to therapy.