525 research outputs found
Prognostic impact of circulating Her-2-reactive T-cells producing pro- and/or anti-inflammatory cytokines in elderly breast cancer patients
Clinico-pathological characteristics of younger and older patients. (DOCX 15Â kb
Gene Expression Profiling of Bronchoalveolar Lavage Cells Preceding a Clinical Diagnosis of Chronic Lung Allograft Dysfunction.
BackgroundChronic Lung Allograft Dysfunction (CLAD) is the main limitation to long-term survival after lung transplantation. Although CLAD is usually not responsive to treatment, earlier identification may improve treatment prospects.MethodsIn a nested case control study, 1-year post transplant surveillance bronchoalveolar lavage (BAL) fluid samples were obtained from incipient CLAD (n = 9) and CLAD free (n = 8) lung transplant recipients. Incipient CLAD cases were diagnosed with CLAD within 2 years, while controls were free from CLAD for at least 4 years following bronchoscopy. Transcription profiles in the BAL cell pellets were assayed with the HG-U133 Plus 2.0 microarray (Affymetrix). Differential gene expression analysis, based on an absolute fold change (incipient CLAD vs no CLAD) >2.0 and an unadjusted p-value ≤0.05, generated a candidate list containing 55 differentially expressed probe sets (51 up-regulated, 4 down-regulated).ResultsThe cell pellets in incipient CLAD cases were skewed toward immune response pathways, dominated by genes related to recruitment, retention, activation and proliferation of cytotoxic lymphocytes (CD8+ T-cells and natural killer cells). Both hierarchical clustering and a supervised machine learning tool were able to correctly categorize most samples (82.3% and 94.1% respectively) into incipient CLAD and CLAD-free categories.ConclusionsThese findings suggest that a pathobiology, similar to AR, precedes a clinical diagnosis of CLAD. A larger prospective investigation of the BAL cell pellet transcriptome as a biomarker for CLAD risk stratification is warranted
Cytomegalovirus seropositivity is associated with glucose regulation in the oldest old. Results from the Leiden 85-plus Study
Background: Cytomegalovirus (CMV) infection has been reported to contribute to the pathogenesis of type 1 diabetes and post-transplantation diabetes. However, CMV infection has not been evaluated as a possible risk factor for type 2 diabetes. Our aim was to investigate potential associations between CMV seropositivity, CMV IgG antibody level and glucose regulation in the oldest old.Results: CMV seropositive subjects were more likely to have type 2 diabetes (17.2% vs 7.9%, p = 0.016), had a higher level of HbA1c (p = 0.014) and higher non-fasting glucose (p = 0.024) in the oldest olds. These associations remained significant after adjustment for possible confounders. CMV IgG antibody level was not significantly associated with glucose regulation (all p > 0.05).Conclusions: In the oldest old, CMV seropositivity is significantly associated with various indicators of glucose regulation. This finding suggests that CMV infection might be a risk factor for the development of type 2 diabetes in the elderly
Prothymosin a and a prothymosin α-derived peptide enhance TH1-type immune responses against defined HER-2/neu epitopes
Background:
Active cancer immunotherapies are beginning to yield clinical benefit, especially those using peptide-pulsed dendritic cells (DCs). Different adjuvants, including Toll-like receptor (TLR) agonists, commonly co-administered to cancer patients as part of a DC-based vaccine, are being widely tested in the clinical setting. However, endogenous DCs in tumor-bearing individuals are often dysfunctional, suggesting that ex vivo educated DCs might be superior inducers of anti-tumor immune responses. We have previously shown that prothymosin alpha (proTα) and its immunoreactive decapeptide proTα(100–109) induce the maturation of human DCs in vitro. The aim of this study was to investigate whether proTα- or proTα(100–109)-matured DCs are functionally competent and to provide preliminary evidence for the mode of action of these agents.
Results:
Monocyte-derived DCs matured in vitro with proTα or proTα(100–109) express co-stimulatory molecules and secrete pro-inflammatory cytokines. ProTα- and proTα(100–109)-matured DCs pulsed with HER-2/neu peptides induce TH1-type immune responses, prime autologous naïve CD8-positive (+) T cells to lyse targets expressing the HER-2/neu epitopes and to express a polyfunctional profile, and stimulate CD4+ T cell proliferation in an HER-2/neu peptide-dependent manner. DC maturation induced by proTα and proTα(100–109) is likely mediated via TLR-4, as
25 shown by assessing TLR-4 surface expression and the levels of the intracellular adaptor molecules TIRAP, MyD88 and TRIF.
Conclusions:
Our results suggest that proTα and proTα(100–109) induce both the maturation and the T cell stimulatory capacity of DCs. Although further studies are needed, evidence for a possible proTα and proTα(100–109) interaction with TLR-4 is provided. The initial hypothesis that proTα and the proTα-derived immunoactive decapeptide act as “alarmins”, provides a rationale for their eventual use as adjuvants in DC-based anti-cancer immunotherapy
Immune profiling of Alzheimer patients
Alzheimer's disease (AD) is characterized by extracellular senile plaques in the brain, containing amyloid-β peptide (Aβ). We identify immunological differences between AD patients and age-matched controls greater than those related to age itself. The biggest differences were in the CD4+ rather than the CD8+ T cell compartment resulting in lower proportions of naïve cells, more late-differentiated cells and higher percentages of activated CD4+CD25+ T cells without a Treg phenotype in AD patients. Changes to CD4+ cells might be the result of chronic stimulation by Aβ present in the blood. These findings have implications for diagnosis and understanding the aetiology of the diseas
Early-life environment influencing susceptibility to cytomegalovirus infection: evidence from the Leiden Longevity Study and the Longitudinal Study of Aging Danish Twins
SUMMARYHuman cytomegalovirus (CMV) is a common herpesvirus establishing lifelong persisting infection, which has been implicated in immunosenescence and mortality in the elderly. Little is known about how and when susceptibility to CMV infection is determined. We measured CMV seroprevalence in two genetically informative cohorts. From the Leiden Longevity Study (LLS) we selected long-lived sib-pairs (n=844) and their middle-aged offspring and the offspring's partners (n=1452). From the Longitudinal Study of Aging Danish Twins (LSADT) 604 (302 pairs) same-sex monozygotic (MZ) and dizygotic (DZ) twins aged 73-94 years were included (n=302 pairs). Offspring of the long-lived LLS participants had significantly lower seroprevalence of CMV compared to their partners (offspring: 42% vs. partners: 51%, P=0·003). Of 372 offspring living with a CMV-positive partner, only 58% were infected. The corresponding number for partners was 71% (P<0·001). In the LSADT, MZ and DZ twins had high and similar CMV-positive concordance rates (MZ: 90% vs. DZ: 88%, P=0·51) suggesting that shared family environment accounts for the similarity within twin pairs. Our findings suggest that susceptibility to CMV infection - even under continuous within-partnership exposure - appears to be more strongly influenced by early-life environment than by genetic factors and adult environment.Pathophysiology, epidemiology and therapy of agein
Peripheral blood T-cell signatures from high-resolution immune phenotyping of γδ and αβ T-cells in younger and older subjects in the Berlin Aging Study II
Background Aging and latent infection with Cytomegalovirus (CMV) are thought
to be major factors driving the immune system towards immunosenescence,
primarily characterized by reduced amounts of naïve T-cells and increased
memory T-cells, potentially associated with higher morbidity and mortality.
The composition of both major compartments, γδ as well as αβ T-cells, is
altered by age and CMV, but detailed knowledge of changes to the γδ subset is
currently limited. Results Here, we have surveyed a population of 73 younger
(23–35 years) and 144 older (62–85 years) individuals drawn from the Berlin
Aging Study II, investigating the distribution of detailed differentiation
phenotypes of both γδ and αβ T-cells. Correlation of frequencies and absolute
counts of the identified phenotypes with age and the presence of CMV revealed
a lower abundance of Vδ2-positive and a higher amount of Vδ1-positive cells.
We found higher frequencies of late-differentiated and lower frequencies of
early-differentiated cells in the Vδ1+ and Vδ1-Vδ2-, but not in the Vδ2+
populations in elderly CMV-seropositive individuals confirming the association
of these Vδ2-negative cells with CMV-immunosurveillance. We identified the
highest Vδ1:Vδ2 ratios in the CMV-seropositive elderly. The observed increased
CD4:CD8 ratios in the elderly were significantly lower in CMV-seropositive
individuals, who also possessed a lower naïve and a larger late-differentiated
compartment of CD8+ αβ T-cells, reflecting the consensus in the literature.
Conclusions Our findings illustrate in detail the strong influence of CMV on
the abundance and differentiation pattern of γδ T-cells as well as αβ T-cells
in older and younger people. Mechanisms responsible for the phenotypic
alterations in the γδ T-cell compartment, associated both with the presence of
CMV and with age require further clarification
Cytotoxic polyfunctionality maturation of cytomegalovirus-pp65-specific CD4 + and CD8 + T-cell responses in older adults positively correlates with response size
Cytomegalovirus (CMV) infection is one of the most common persistent viral infections in humans worldwide and is epidemiologically associated with many adverse health consequences during aging. Previous studies yielded conflicting results regarding whether large, CMV-specific T-cell expansions maintain their function during human aging. In the current study, we examined the in vitro CMV-pp65-reactive T-cell response by comprehensively studying five effector functions (i.e., interleukin-2, tumor necrosis factor-α, interferon-γ, perforin, and CD107a expression) in 76 seropositive individuals aged 70 years or older. Two data-driven, polyfunctionality panels (IL-2-associated and cytotoxicity-associated) derived from effector function co-expression patterns were used to analyze the results. We found that, CMV-pp65-reactive CD8 + and CD4 + T cells contained similar polyfunctional subsets, and the level of polyfunctionality was related to the size of antigen-specific response. In both CD8 + and CD4 + cells, polyfunctional cells with high cytotoxic potential accounted for a larger proportion of the total response as the total response size increased. Notably, a higher serum CMV-IgG level was positively associated with a larger T-cell response size and a higher level of cytotoxic polyfunctionality. These findings indicate that CMV-pp65-specific CD4 + and CD8 + T cell undergo simultaneous cytotoxic polyfunctionality maturation during aging
Immunosenescence and Cytomegalovirus: where do we stand after a decade?
AbstractSince Looney at al. published their seminal paper a decade ago it has become clear that many of the differences in T cell immunological parameters observed between young and old people are related to the age-associated increasing prevalence of infection with the persistent beta-herpesvirus HHV-5 (Cytomegalovirus). Ten years later, studies suggest that hallmark age-associated changes in peripheral blood T cell subset distribution may not occur at all in people who are not infected with this virus. Whether the observed changes are actually caused by CMV is an open question, but very similar, rapid changes observed in uninfected patients receiving CMV-infected kidney grafts are consistent with a causative role. This meeting intensively discussed these and other questions related to the impact of CMV on human immune status and its relevance for immune function in later life.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
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Impact of ageing and a synbiotic on the immune response to seasonal influenza vaccination; a randomised controlled trial
Background & Aims
Ageing increases risk of respiratory infections and impairs the response to influenza vaccination. Pre- and probiotics offer an opportunity to modulate anti-viral defenses and the response to vaccination via alteration of the gut microbiota. This study investigated the effect of a novel probiotic, Bifidobacterium longum bv. infantis CCUG 52486, combined with a prebiotic, gluco-oligosaccharide, on the B and T cell response to seasonal influenza vaccination in young and older subjects.
Methods
In a double-blind, randomized controlled trial, 58 young (18-35y) and 54 older (60-85y) subjects were supplemented with the synbiotic for 8 weeks. At 4 weeks they were administered with a seasonal influenza vaccine. B and T cell phenotype and responsiveness to in vitro re-stimulation with the vaccine were assessed at baseline, 4, 6 and 8 weeks.
Results
B and T cell profiles differed markedly between young and older subjects. Vaccination increased numbers of memory, IgA+ memory, IgG+ memory and total IgG+ B cells in young subjects, but failed to do so in older subjects and did not significantly alter T cell subsets. Seroconversion to the H1N1 subunit in the older subjects was associated with higher post-vaccination numbers of plasma B cells, but seroconversion was less consistently associated with T cell phenotype. B and T cell subsets from both young and older subjects demonstrated a strong antigen-specific recall challenge, and although not influenced by age, responsiveness to the recall challenge was associated with seroconversion. In older subjects, CMV seropositivity was associated with a significantly lower recall response to the vaccine, but the synbiotic did not affect the responsiveness of B or T cells to re-stimulation with influenza vaccine.
Conclusions
Antigen-specific B and T cell activation following an in vitro recall challenge with the influenza vaccine was influenced by CMV seropositivity, but not by a synbiotic
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