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Bone marrow plasma cells (BMPC) are the correlate of humoral immunity, consistently releasing antibodies into the bloodstream. It remains unclear if BMPC reflect different activation environments or maturation of their precursors. Here we define human BMPC heterogeneity and track the recruitment of antibody-secreting cells (ASC) from SARS-CoV-2 vaccine immune reactions to the bone marrow (BM). Trajectories based on single-cell transcriptomes and repertoires of peripheral and BM ASC reveal sequential colonisation of BMPC compartments. In activated B cells, IL-21 suppresses CD19 expression, indicating that CD19low-BMPC are derived from follicular, while CD19high-BMPC originate from extrafollicular immune reactions. In primary immune reactions, both CD19low- and CD19high-BMPC compartments are populated. In secondary immune reactions, most BMPC are recruited to CD19high-BMPC compartments, reflecting their origin from extrafollicular reactivations of memory B cells. A pattern also observable in vaccinated-convalescent individuals and upon diphtheria/tetanus/pertussis recall-vaccination. Thus, BMPC diversity reflects the evolution of a given humoral immune response.
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Antígenos CD19 , Medula Óssea , Interleucinas , Plasmócitos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Células Produtoras de Anticorpos/imunologia , Antígenos CD19/imunologia , Antígenos CD19/metabolismo , Linfócitos B/imunologia , Medula Óssea/imunologia , Células da Medula Óssea/imunologia , Células da Medula Óssea/citologia , COVID-19/imunologia , COVID-19/virologia , Vacina contra Difteria, Tétano e Coqueluche/imunologia , Imunidade Humoral/imunologia , Interleucinas/imunologia , Interleucinas/metabolismo , Plasmócitos/imunologia , SARS-CoV-2/imunologia , Análise de Célula Única , VacinaçãoRESUMO
BACKGROUND: Digestibility is a primary factor in determining the quality of dietary protein. Microbial protease supplementation may be a strategy for improving protein digestion and subsequent postprandial plasma amino acid availability. OBJECTIVES: To assess the effect of co-ingesting a microbial protease mixture with pea protein on postprandial plasma amino acid concentrations. DESIGN: A mixture of 3 microbial protease preparations (P3) was tested for proteolytic efficacy in an in vitro static simulation of gastrointestinal digestion. Subsequently, in a randomized, double-blind, placebo-controlled crossover trial, 24 healthy adults (27 ± 4 y; 12 females, 12 males) ingested 25 g pea protein isolate (20 g protein, 2.2 g fat) with either P3 or maltodextrin placebo (PLA). Blood samples were collected at baseline and throughout a 0â5 h postprandial period and both the early (0-2 h) iAUC and total (0-5 h) iAUC were examined. RESULTS: Plasma glucose concentrations decreased in both conditions (P < 0.001), with higher concentrations after P3 ingestion compared with PLA (P < 0.001). Plasma insulin concentrations increased for both conditions (P < 0.001) with no difference between conditions (P = 0.331). Plasma total amino acid (TAA) concentrations increased over time (P < 0.001) with higher concentrations observed for P3 compared with PLA (P = 0.010) during the 0â5 h period. There was a trend for elevated essential amino acid (EAA) concentrations for P3 compared with PLA (P = 0.099) during the 0â5 h postprandial period but not for leucine (P = 0.282) or branched-chain amino acids (BCAA, P = 0.410). The early net exposure (0â2 h iAUC) to amino acids (leucine, BCAA, EAA, and TAA) was higher for P3 compared with PLA (all, P < 0.05). CONCLUSIONS: Microbial protease co-ingestion increases plasma TAA concentrations (0-5 h) and leucine, BCAA, EAA, and TAA availability in the early postprandial period (0â2 h) compared with ingesting pea protein with placebo in healthy adults.
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Aminoácidos , Estudos Cross-Over , Suplementos Nutricionais , Proteínas de Ervilha , Período Pós-Prandial , Humanos , Adulto , Masculino , Feminino , Método Duplo-Cego , Aminoácidos/sangue , Aminoácidos/metabolismo , Adulto Jovem , Insulina/sangue , Glicemia/metabolismo , Peptídeo Hidrolases/sangue , Peptídeo Hidrolases/metabolismo , Digestão/efeitos dos fármacos , Pisum sativumRESUMO
Despite its importance in poultry research, there is lack of standardized and practical techniques to measure intestinal permeability in a noninvasive manner. Therefore, this research sought to standardize a procedure using lactulose (Lac) and mannitol (Man) to measure intestinal barrier function in broilers. Twenty-one-day-old male and female Ross 308 birds were orally gavaged (either 2 mL/kg BW or fixed 3 mL per bird) with a solution containing 5 to 25 g Lac and 1 to 5 g Man dissolved in pure water to reach 100 mL of final solution. Feed withdrawal (FW; 2-24-h duration) prior to dosing with Lac and Man (LacMan) was mainly used to induce graded intestinal permeability. Blood samples were collected at 60-, 90-, or 120-min after LacMan dosing using serum or plasma (K2EDTA and/or Na-Heparin) blood tubes. Lac and Man concentrations were quantified by HPLC. Plasma samples collected 90-min after LacMan dosing elicited the least variable response (22.4% vs. 22.8% or 23.4% CV when compared with 60- and 120-min sampling time-points, respectively), and both markers were detectable after administering a solution containing the lowest concentration of Lac and Man. However, analytical problems arose when using Na-Heparin anticoagulant as high glucose levels interfered with Lac quantification. Upon improving the chromatographic technique, it became evident that a 24-h FW increased (P < 0.01) Lac concentrations. In the last trial, a more severe glucose interference was observed, resulting in no Lac detection within an entire treatment group. Twelve hours of FW increased (P < 0.01) Man concentration in the plasma of birds receiving the solution containing 3 g Man, but had no effect on the birds receiving the solution containing 5 g Man. A 24-h FW did not affect the Man concentrations in birds receiving the solution containing either 3 or 5 g Man. With inconsistency of Lac detection throughout our trials, it was concluded that the combination of Lac and Man is an unreliable marker to predict intestinal barrier function in broilers.
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Galinhas , Lactulose , Humanos , Masculino , Animais , Feminino , Galinhas/fisiologia , Função da Barreira Intestinal , Permeabilidade , Manitol , Glucose , HeparinaRESUMO
Sialylated oligosaccharides, including 3'-sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL), comprise a large portion of human milk and have been known to support development over the first year of life. While research has investigated the impact of early-life supplementation, longer-term supplementation remains relatively unexplored. Consequently, the following study assesses the impact of supplementation of either 3'-SL or 6'-SL on growth performance, tolerance, and brain sialic acid concentrations. Two-day-old piglets (n = 75) were randomly assigned to a commercial milk replacer ad libitum without or with 3'-SL or 6'-SL (added at 0.2673% on an as-is basis). Daily body weight and feed disappearance were recorded to assess growth performance and tolerance. Pigs were euthanized for sample collection on postnatal day 33 (n = 30) or 61 (n = 33), respectively. Across growth performance, clinical chemistry and hematology, histomorphology, and sialic acid quantification, dietary differences were largely unremarkable at either time-point. Overall, SA was well-tolerated both short-term and long-term.
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BACKGROUND: Protein is most commonly consumed as whole foods as opposed to single nutrients. However, the food matrix regulation of the postprandial muscle protein synthetic response has received little attention. OBJECTIVES: The purpose of this study was to assess the effects of eating salmon (SAL) and of ingesting the same nutrients as an isolated mixture of crystalline amino acids and fish oil (ISO) on the stimulation of postexercise myofibrillar protein synthesis (MPS) and whole-body leucine oxidation rates in healthy young adults. METHODS: Ten recreationally active adults (24 ± 4 y; 5 men, 5 women) performed an acute bout of resistance exercise, followed by the ingestion of SAL or ISO in a crossover fashion. Blood, breath, and muscle biopsies were collected at rest and after exercise during primed continuous infusions of L-[ring-2H5]phenylalanine and L-[1-13C]leucine. All data are presented as means ± SD and/or mean differences (95% CIs). RESULTS: Postprandial essential amino acid (EAA) concentrations peaked earlier (P = 0.024) in the ISO group than those in the SAL group. Postprandial leucine oxidation rates increased over time (P < 0.001) and peaked earlier in the ISO group (1.239 ± 0.321 nmol/kg/min; 63 ± 25 min) than those in the SAL group (1.230 ± 0.561 nmol/kg/min; 105 ± 20 min; P = 0.003). MPS rates for SAL (0.056 ± 0.022 %/h; P = 0.001) and ISO (0.046 ± 0.025 %/h; P = 0.025) were greater than the basal rates (0.020 ± 0.011 %/h) during the 0- to 5-h recovery period, with no differences between conditions (P = 0.308). CONCLUSION: We showed that the postexercise ingestion of SAL or ISO stimulate postexercise MPS rates with no differences between the conditions. Thus, our results indicate that ingesting protein from SAL as a whole-food matrix is similarly anabolic to ISO in healthy young adults. This trial was registered at www. CLINICALTRIALS: gov as NCT03870165.
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Proteínas Alimentares , Salmão , Animais , Feminino , Proteínas Alimentares/metabolismo , Ingestão de Alimentos , Leucina/farmacologia , Músculo Esquelético , Nutrientes , Período Pós-Prandial , Salmão/metabolismoRESUMO
Rationale: Pulmonary sarcoidosis is generally presumed to be a T-helper cell type 1- and macrophage-driven disease. However, mouse models have recently revealed that chronically inflamed lung tissue can also comprise T follicular helper (Tfh)-like cells and represents a site of active T-cell/B-cell cooperation. Objectives: To assess the role of pulmonary Tfh- and germinal center-like lymphocytes in sarcoidosis. Methods: BAL fluid, lung tissue, and peripheral blood samples from patients with sarcoidosis were analyzed by flow cytometry, immunohistology, RNA sequencing, and in vitro T-cell/B-cell cooperation assays for phenotypic and functional characterization of germinal center-like reactions in inflamed tissue. Measurements and Main Results: We identified a novel population of Tfh-like cells characterized by high expression of the B helper molecules CD40L and IL-21 in BAL of patients with sarcoidosis. Transcriptome analysis further confirmed a phenotype that was both Tfh-like and tissue resident. BAL T cells provided potent help for B cells to differentiate into antibody-producing cells. In lung tissue, we observed large peribronchial infiltrates with T and B cells in close contact, and many IgA+ plasmablasts. Most clusters were nonectopic; that is, they did not contain follicular dendritic cells. Patients with sarcoidosis also showed elevated levels of PD-1high CXCR5- CD40Lhigh ICOShigh Tfh-like cells, but not classical CXCR5+ Tfh cells, in the blood. Conclusions: Active T-cell/B-cell cooperation and local production of potentially pathogenic antibodies in the inflamed lung represents a novel pathomechanism in sarcoidosis and should be considered from both diagnostic and therapeutic perspectives.
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Linfócitos B/imunologia , Centro Germinativo/imunologia , Pulmão/imunologia , Sarcoidose Pulmonar/imunologia , Células T Auxiliares Foliculares/imunologia , Adulto , Idoso , Biomarcadores/sangue , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Sarcoidose Pulmonar/sangue , Sarcoidose Pulmonar/patologiaRESUMO
OBJECTIVE: The prebiotic fiber inulin has been studied in individuals undergoing hemodialysis (HD) due to its ability to reduce gut microbiota-derived uremic toxins. However, studies examining the effects of inulin on the gut microbiota and derived metabolites are limited in these patients. We aimed to assess the impact of a 4-week supplementation of inulin on the gut microbiota composition and microbial metabolites of patients on HD. DESIGN AND METHODS: In a randomized, double-blind, placebo-controlled, crossover study, twelve HD patients (55 ± 10 y, 50% male, 58% Black American, BMI 31.6 ± 8.9 kg/m2, 33% diabetes mellitus) were randomized to consume inulin [10 g/d for females; 15 g/d for males] or maltodextrin [6 g/d for females; 9 g/d for males] for 4 weeks, with a 4-week washout period. We assessed the fecal microbiota composition, fecal metabolites (short-chain fatty acids (SCFA), phenols, and indoles), and plasma indoxyl sulfate and p-cresyl sulfate. RESULTS: At baseline, factors that explained the gut microbiota variability included BMI category and type of phosphate binder prescribed. Inulin increased the relative abundance of the phylum Verrucomicrobia and its genus Akkermansia (P interaction = 0.045). Inulin and maltodextrin resulted in an increased relative abundance of the phylum Bacteroidetes and its genus Bacteroides (P time = 0.04 and 0.03, respectively). Both treatments increased the fecal acetate and propionate (P time = 0.032 and 0.027, respectively), and there was a trend toward increased fecal butyrate (P time = 0.06). Inulin did not reduce fecal p-cresol or indoles, or plasma concentrations of p-cresyl sulfate or indoxyl sulfate. CONCLUSIONS: A 4-week supplementation of inulin did not lead to major shifts in the fecal microbiota and gut microbiota-derived metabolites. This may be due to high variability among participants and an unexpected increase in fecal excretion of SCFA with maltodextrin. Larger studies are needed to determine the effects of prebiotic fibers on the gut microbiota and clinical outcomes to justify their use in patients on HD.
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Microbioma Gastrointestinal , Inulina , Estudos Cross-Over , Feminino , Humanos , Masculino , Projetos Piloto , Prebióticos , Diálise Renal , Toxinas UrêmicasRESUMO
Follicular helper T (Tfh) cells play a key role in B cell activation and differentiation. Within recent years, distinct subsets of follicular T cells, including regulatory and cytotoxic T cells, have been identified. Apart from classical Tfh cells in secondary lymphoid organs, Tfh-like cells are found in chronically inflamed nonlymphoid tissues. Here, we provide protocols to identify different follicular T cell subsets in murine and human tissues by flow cytometry. This chapter also contains an immunization protocol for the induction of large numbers of Tfh cells in mice.
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Citometria de Fluxo , Subpopulações de Linfócitos T/imunologia , Transferência Adotiva , Animais , Biomarcadores/metabolismo , Centro Germinativo/citologia , Humanos , Imunização , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Receptores de Antígenos de Linfócitos T/metabolismo , Projetos de Pesquisa , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/transplante , Fluxo de TrabalhoRESUMO
Under chronic inflammatory conditions, T and B cells are frequently found in nonlymphoid tissues. We recently identified a follicular helper-like T cell population in inflamed lung tissue, which drives the local differentiation of antigen-specific B cells into germinal center-like cells and plasma blasts. Here, we describe a lung inflammation mouse model, which is ideally suited to analyze antigen-specific T and B cells in secondary lymphoid organs and inflamed nonlymphoid tissue in parallel.
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Subpopulações de Linfócitos B/imunologia , Citometria de Fluxo , Pulmão/imunologia , Pneumonia/imunologia , Subpopulações de Linfócitos T/imunologia , Transferência Adotiva , Animais , Subpopulações de Linfócitos B/metabolismo , Subpopulações de Linfócitos B/transplante , Biomarcadores/metabolismo , Separação Celular , Modelos Animais de Doenças , Imunização , Pulmão/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pneumonia/metabolismo , Projetos de Pesquisa , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/transplante , Fluxo de TrabalhoRESUMO
Middle East respiratory syndrome coronavirus (MERS-CoV) is the causative agent of a severe respiratory disease associated with more than 2468 human infections and over 851 deaths in 27 countries since 2012. There are no approved treatments for MERS-CoV infection although a combination of lopinavir, ritonavir and interferon beta (LPV/RTV-IFNb) is currently being evaluated in humans in the Kingdom of Saudi Arabia. Here, we show that remdesivir (RDV) and IFNb have superior antiviral activity to LPV and RTV in vitro. In mice, both prophylactic and therapeutic RDV improve pulmonary function and reduce lung viral loads and severe lung pathology. In contrast, prophylactic LPV/RTV-IFNb slightly reduces viral loads without impacting other disease parameters. Therapeutic LPV/RTV-IFNb improves pulmonary function but does not reduce virus replication or severe lung pathology. Thus, we provide in vivo evidence of the potential for RDV to treat MERS-CoV infections.
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Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Infecções por Coronavirus/tratamento farmacológico , Interferon beta/uso terapêutico , Lopinavir/uso terapêutico , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Ritonavir/uso terapêutico , Monofosfato de Adenosina/uso terapêutico , Alanina/uso terapêutico , Animais , Antivirais/uso terapêutico , Carboxilesterase/genética , Infecções por Coronavirus/patologia , Combinação de Medicamentos , Desenvolvimento de Medicamentos , Feminino , Humanos , Lesão Pulmonar/patologia , Masculino , Camundongos , Camundongos Knockout , Carga Viral , Replicação Viral/efeitos dos fármacosRESUMO
Carbohydrate (CHO) ingestion is an established strategy to improve endurance performance. Race fuels should not only sustain performance but also be readily digested and absorbed. Potatoes are a whole-food-based option that fulfills these criteria, yet their impact on performance remains unexamined. We investigated the effects of potato purée ingestion during prolonged cycling on subsequent performance vs. commercial CHO gel or a water-only condition. Twelve cyclists (70.7 ± 7.7 kg, 173 ± 8 cm, 31 ± 9 yr, 22 ± 5.1% body fat; means ± SD) with average peak oxygen consumption (VÌo2peak) of 60.7 ± 9.0 mL·kg-1·min-1 performed a 2-h cycling challenge (60-85% VÌo2peak) followed by a time trial (TT; 6 kJ/kg body mass) while consuming potato, gel, or water in a randomized-crossover design. The race fuels were administered with [U-13C6]glucose for an indirect estimate of gastric emptying rate. Blood samples were collected throughout the trials. Blood glucose concentrations were higher (P < 0.001) in potato and gel conditions compared with water condition. Blood lactate concentrations were higher (P = 0.001) after the TT completion in both CHO conditions compared with water condition. TT performance was improved (P = 0.032) in both potato (33.0 ± 4.5 min) and gel (33.0 ± 4.2 min) conditions compared with water condition (39.5 ± 7.9 min). Moreover, no difference was observed in TT performance between CHO conditions (P = 1.00). In conclusion, potato and gel ingestion equally sustained blood glucose concentrations and TT performance. Our results support the effective use of potatoes to support race performance for trained cyclists.NEW & NOTEWORTHY The ingestion of concentrated carbohydrate gels during prolonged exercise has been shown to promote carbohydrate availability and improve exercise performance. Our study aim was to expand and diversify race fueling menus for athletes by providing an evidence-based whole-food alternative to the routine ingestion of gels during training and competition. Our work shows that russet potato ingestion during prolonged cycling is as effective as carbohydrate gels to support exercise performance in trained athletes.
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Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Carboidratos da Dieta/administração & dosagem , Solanum tuberosum , Adulto , Glicemia , Digestão , Feminino , Humanos , Masculino , Esforço Físico , Adulto JovemRESUMO
T follicular helper (Tfh) cells are a specialized T cell subset that regulates the long-lived production of highly specific Abs by B cells during the germinal center (GC) reaction. However, the transcriptional network sustaining the Tfh cell phenotype and function is still incompletely understood. In this study, we identify the transcription factor Bach2 as a central negative regulator of Tfh cells. Ectopic overexpression of Bach2 in murine Tfh cells resulted in a rapid loss of their phenotype and subsequent breakdown of the GC response. Low Bach2 expression levels are required to maintain high expression of the signature cytokine IL-21, the coinhibitory receptor TIGIT and the transcriptional repressor Bcl-6. In stark contrast to the regulatory network in GC B cells, Bach2 in Tfh cells is not coexpressed with Bcl-6 at high levels to inhibit the antagonizing factor Blimp-1, but suppresses Bcl-6 by direct binding to the promoter. These data reveal that by replacing an activating complex of Batf and Irf-4 at the Bcl-6 promoter, Bach2 regulates the transcriptional network of Tfh cells in a different way, as in GC B cells.
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Fatores de Transcrição de Zíper de Leucina Básica , Regulação da Expressão Gênica/imunologia , Centro Germinativo/imunologia , Proteínas Proto-Oncogênicas c-bcl-6 , Linfócitos T Reguladores/imunologia , Transcrição Gênica/imunologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Centro Germinativo/citologia , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/imunologia , Interleucinas/genética , Interleucinas/imunologia , Camundongos , Camundongos Knockout , Regiões Promotoras Genéticas/imunologia , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/imunologia , Linfócitos T Reguladores/citologiaRESUMO
Observers falsely remember seeing beyond the bounds of a photograph (i.e., boundary extension [BE]). Do observers "zoom in" when viewing negative emotion photographs, resulting in boundary restriction (Safer, Christianson, Autry, & Österlund, 1998)? Studies have yielded inconsistent outcomes, perhaps because emotional valence was compared across photographs of completely different scenes. To control physical scene structure, two contrasting (negative vs. positive) emotional versions of the same scenes were created by dramatically changing individuals' facial expressions; 14 such scene pairs were selected based on participants' (n = 134) ratings of the emotional valence elicited. We attempted to enhance sensitivity to negative scene content by including participants who scored either high (n = 104) or low (n = 104) on trait rumination, which is characterized by repetitive analysis of negative mood and a narrowing of attention. They viewed either all negative or all positive emotion scenes (15 s each). These scenes were repeated at test and rated as "the same," "closer-up," or "farther away" than the stimulus view (on a 5-point scale). Participants in all groups exhibited BE, but neither emotional valence nor trait rumination affected performance, even though mood induction had occurred. Only physical scene context affected BE (irrespective of the emotional valence of the scenes). Results underscore the importance of controlling physical scene context in tests of the effect of emotion on spatial memory. The resilience of BE to negative-mood-inducing scenes is discussed in terms of the adaptive value of anticipating one's surroundings while navigating through scenes in the world. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
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Atenção/fisiologia , Emoções/fisiologia , Rememoração Mental/fisiologia , Feminino , Humanos , MasculinoRESUMO
B-cell interaction with follicular helper T cells and subsequent differentiation of B cells into high-affinity APCs normally takes place in secondary lymphoid organs. The costimulator ICOS plays a key role in this process and is therefore considered as an attractive target to modulate exaggerated B-cell responses in autoimmune or allergic diseases. Inflamed tissues were recently recognized as additional sites of active T-cell/B-cell interaction. To analyze whether ICOS costimulation is also important there, we employed a mouse airway inflammation model that allows direct comparison of immune reactions in the lung-draining lymph node and the lung tissue as well as assessment of the relative importance of dendritic cells versus B cells as APCs. In both organs, ICOS regulated the pool size of antigen-specific T and B cells and B-cell differentiation into germinal center(-like) cells but not into antibody-secreting cells. In the lymph node, lack of ICOS costimulation drastically reduced the frequency of T follicular helper cells but did not affect production of T-helper cell type 2 (Th2) cytokines. Vice versa in the lung tissue, ICOS did not change PD-1 expression on infiltrating T cells but regulated Th2 cytokine production, a process for which ICOS ligand expression on B cells was of particular importance. Taken together, the results of this study show that ICOS differentially regulates effector T cells in secondary lymphoid organs and inflamed tissues but that blockade of the ICOS pathway is suitable to target T cell-dependent B cell responses at both sites.
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Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Inflamação/patologia , Tecido Linfoide/metabolismo , Linfócitos T/metabolismo , Animais , Células Apresentadoras de Antígenos/metabolismo , Citocinas/biossíntese , Modelos Animais de Doenças , Eosinófilos/metabolismo , Imunoglobulina A/metabolismo , Switching de Imunoglobulina , Imunoglobulina E/metabolismo , Ligante Coestimulador de Linfócitos T Induzíveis/metabolismo , Linfonodos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pneumonia/patologia , Receptor de Morte Celular Programada 1/metabolismoRESUMO
Live attenuated vaccines are generally highly efficacious and often superior to inactivated vaccines, yet the underlying mechanisms of this remain largely unclear. Here we identify recognition of microbial viability as a potent stimulus for follicular helper T cell (TFH cell) differentiation and vaccine responses. Antigen-presenting cells (APCs) distinguished viable bacteria from dead bacteria through Toll-like receptor 8 (TLR8)-dependent detection of bacterial RNA. In contrast to dead bacteria and other TLR ligands, live bacteria, bacterial RNA and synthetic TLR8 agonists induced a specific cytokine profile in human and porcine APCs, thereby promoting TFH cell differentiation. In domestic pigs, immunization with a live bacterial vaccine induced robust TFH cell and antibody responses, but immunization with its heat-killed counterpart did not. Finally, a hypermorphic TLR8 polymorphism was associated with protective immunity elicited by vaccination with bacillus Calmette-Guérin (BCG) in a human cohort. We have thus identified TLR8 as an important driver of TFH cell differentiation and a promising target for TFH cell-skewing vaccine adjuvants.
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Ativação Linfocitária/imunologia , Viabilidade Microbiana/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Receptor 8 Toll-Like/imunologia , Vacinas Atenuadas/imunologia , Adulto , Animais , Formação de Anticorpos/imunologia , Diferenciação Celular/imunologia , Feminino , Humanos , Masculino , SuínosRESUMO
OBJECTIVE: This study, conducted over a 2-year period at 9 sites, describes the outcomes of an evidence-based support program, Operation Family Caregiver, to gain an understanding of how a tailored, problem-solving training could assist military caregivers, who provide care and assistance to those injured, ill, or disabled as a result of war. METHOD: A pre-post research design was employed to examine caregiver burden, depression, health complaints, satisfaction with life, children's anxiety, and problem solving among a convenience sample of caregivers of 128 military service members and veterans. RESULTS: Analysis revealed a decrease in depression, burden, and health complaints and an increase in satisfaction of life and positive problem-solving skills (p < .001). CONCLUSION: This program may be beneficial to caregiving families of military service and veterans living with posttraumatic stress, traumatic brain injury, and/or a physical disability.
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Lesões Encefálicas Traumáticas/enfermagem , Cuidadores/psicologia , Pessoas com Deficiência , Educação não Profissionalizante/métodos , Família/psicologia , Militares , Satisfação Pessoal , Resolução de Problemas , Transtornos de Estresse Pós-Traumáticos/enfermagem , Veteranos , Adulto , Cuidadores/educação , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Seasonal changes in the foodscape force herbivores to select different plant species or plant parts to meet nutritional requirements. We examined whether the search for calorie-rich carbohydrates explained giant panda's selection for bamboo culm over leaves during spring. Leaves and culms were collected from four Phyllostachys bamboos (P. aurea, P. aureosulcata, P. glauca, and P. nuda) once per month over 18-27 months. Monthly changes in annual plant part nutrients were examined, and compared to seasonal foraging behaviors of captive giant pandas. Although total fiber was greater (p<0.0001) in culm (85.6 ± 0.5%) than leaves (55.3 ± 0.4%) throughout the year, culm fiber was at its lowest in spring (79-85%) when culm selection by giant pandas exceeded 70% of their overall diet. Culm starch also was greatest (p = 0.044) during spring (5.5 ± 1.1%) and 2.5-fold the percentage of starch in leaves (2.2 ± 0.6%). The free sugars in spring culm consisted of a high proportion of glucose (35%) and fructose (47%), whereas sucrose made up 42% of the total free sugar content of spring leaves. Bound sugars in culm consisted of 60% glucose and 38% xylose likely representative of hemicellulose. The concentrations of bound sugars (hemicelluloses) in spring culms (543.7 ± 13.0 mg/g) was greater (p<0.001) than in leaves (373.0 ± 14.8 mg/g). These data help explain a long-standing question in giant panda foraging ecology: why consume the plant part with the lowest protein and fat during the energetically intensive spring breeding season? Giant pandas likely prefer spring culm that contains abundant mono- and polysaccharides made more bioavailable as a result of reduced fiber content. These data suggest that phenological changes in bamboo plant part nutrition drive foraging decisions by giant pandas.
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Fenóis/análise , Poaceae/química , Ursidae/fisiologia , Ração Animal/análise , Animais , Animais de Zoológico , Folhas de Planta/química , Caules de Planta/química , Estações do AnoRESUMO
Butyrate possesses negative sensory qualities and is most effectively utilized in the intestine to provide energy to the colonocyte for the maintenance of intestinal health. Butyrate has also shown promise in the treatment of intestinal disorders and diseases such as short bowel syndrome, inflammatory bowel disease, and colon cancer. To modify sensory properties, intestinal release, and butyrate production capabilities, tributyrin (TB) was microencapsulated in whey protein isolate (WPI)-based and gamma-cyclodextrin (GC)-based materials. Using an in vitro digestion and fermentation model, microcapsules containing TB were monitored for their release and production of butyrate in vitro. All samples containing TB showed limited butyrate release (<5%) during oral and gastric stages. In the small intestinal phase, all microcapsules containing TB released approximately 75% of their total butyrate with no significant differences (P > 0.05) across formulations. During the fermentation phase, GC-based microcapsules produced significantly more butyrate (P < 0.001) on a molar basis than all WPI-based microcapsules. Butyrate production increased significantly (P < 0.001) over each time interval with GC-based microcapsules having the highest during the 12 h of fermentation. The GC-based TB encapsulation systems were able to effectively deliver butyrate to the small intestine and generate butyrate in the large intestine. These microcapsules may, therefore, be beneficial for the maintenance of intestinal health and improvement of disease states across all areas of the gastrointestinal tract.
Assuntos
Ácido Butírico/química , Triglicerídeos/química , Cápsulas , Digestão , Sistemas de Liberação de Medicamentos , Fermentação , HumanosRESUMO
The IL-2/IL-2Ralpha (CD25) axis is of central importance for the interplay of effector and regulatory T cells. Nevertheless, the question how different antigen loads are translated into appropriate IL-2 production to ensure adequate responses against pathogens remains largely unexplored. Here we find that at single cell level, IL-2 is binary (digital) and CD25 is graded expressed whereas at population level both parameters show graded expression correlating with the antigen amount. Combining in vivo data with a mathematical model we demonstrate that only this binary IL-2 expression ensures a wide linear antigen response range for Teff and Treg cells under real spatiotemporal conditions. Furthermore, at low antigen concentrations binary IL-2 expression safeguards by its spatial distribution selective STAT5 activation only of closely adjacent Treg cells regardless of their antigen specificity. These data show that the mode of IL-2 secretion is critical to tailor the adaptive immune response to the antigen amount.
Assuntos
Transferência Adotiva , Subunidade alfa de Receptor de Interleucina-2/genética , Interleucina-2/genética , Linfócitos T Citotóxicos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Animais , Regulação da Expressão Gênica , Imunização , Imunofenotipagem , Interleucina-2/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Imunológicos , Ovalbumina/administração & dosagem , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/imunologia , Transdução de Sinais , Análise de Célula Única , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/transplante , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/transplante , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/efeitos dos fármacosRESUMO
We examine the anatomic basis for abstract and concrete lexical representations in semantic memory by assessing patients with focal neurodegenerative disease. Prior evidence from healthy adult studies suggests that there may be an anatomical dissociation between abstract and concrete representations: abstract words more strongly activate the left inferior frontal gyrus relative to concrete words, while concrete words more strongly activate left anterior-inferior temporal regions. However, this double dissociation has not been directly examined. We test this dissociation in two patient groups with focal cortical atrophy in each of these regions, the behavioral variant of Frontotemporal Degeneration (bvFTD) and the semantic variant of Primary Progressive Aphasia (svPPA). We administered an associativity judgment task for abstract and concrete words, where subjects select which of two words is best associated with a given target word. Both bvFTD and svPPA patients were significantly impaired in their overall performance compared to controls. While controls treated concrete and abstract words equally, we found a category-specific double dissociation in patients' judgments: bvFTD patients showed a concreteness effect (CE), with significantly worse performance for abstract compared to concrete words, while svPPA patients showed reversal of the CE, with significantly worse performance for concrete over abstract words. Regression analyses also revealed an anatomic double dissociation: The CE is associated with inferior frontal atrophy in bvFTD, while reversal of the CE is associated with left anterior-inferior temporal atrophy in svPPA. These results support a cognitive and anatomic model of semantic memory organization where abstract and concrete representations are supported by dissociable neuroanatomic substrates.