Latent viral reactivation is associated with changes in plasma antimicrobial protein concentrations during long-duration spaceflight

NASA Astrophysics Data System (ADS)

Spielmann, G.; Laughlin, M. S.; Kunz, H.; Crucian, B. E.; Quiriarte, H. D.; Mehta, S. K.; Pierson, D. L.; Simpson, R. J.

2018-05-01

Long duration spaceflights are associated with profound dysregulation of the immune system and latent viral reactivations. However, little is known on the impact of long duration spaceflight on innate immunity which raises concerns on crewmembers' ability to fight infections during a mission. The aim of this study was to determine the effects of spaceflight on plasma antimicrobial proteins (AMPs) and how these changes impact latent herpesvirus reactivations. Plasma, saliva and urine samples were obtained from 23 crewmembers before, during and after a 6-month mission on the International Space Station (ISS). Plasma AMP concentrations were determined by ELISA, and saliva Epstein-Barr virus (EBV) and varicella zoster virus (VZV) and urine cytomegalovirus (CMV) DNA levels were quantified by Real-Time PCR. There was a non-significant increase in plasma HNP1-3 and LL-37 during the early and middle stages of the missions, which was significantly associated with changes in viral DNA during and after spaceflight. Plasma HNP1-3 and Lysozyme increased at the late mission stages in astronauts who had exhibited EBV and VZV reactivations during the early flight stages. Following return to Earth and during recovery, HNP1-3 and lysozyme concentrations were associated with EBV and VZV viral DNA levels, reducing the magnitude of viral reactivation. Reductions in plasma LL-37 upon return were associated with greater CMV reactivation. This study shows that biomarkers of innate immunity appeared to be partially restored after 6-months in space and suggests that following adaptation to the space environment, plasma HNP1-3 and lysozyme facilitate the control of EBV and VZV reactivation rate and magnitude in space and upon return on earth. However, the landing-associated decline in plasma LL-37 may enhance the rate of CMV reactivation in astronauts following spaceflight, potentially compromising crewmember health after landing.

Consequences of Longterm-Confinement and Hypobaric Hypoxia on Immunity in the Antarctic Concordia Environment

NASA Technical Reports Server (NTRS)

Crucian, Brian; Chouker, Alexander; Pierson, Duane; Mehta, Satish; Stowe, Raymond; Salam, Alex; Sams, Clarence

2010-01-01

This slide presentation reviews the affects of longterm-confinement and hypobaric hypoxia on immunity in the Antarctic Concordia environment. It includes information on spaceflight-associated immune dysregulation, immune-related knowledge gaps, and ground-based space flight analogs.

Plasma Cytokine Concentrations Indicate In-vivo Hormonal Regulation of Immunity is Altered During Long-Duration Spaceflight

NASA Technical Reports Server (NTRS)

Crician, Brian E.; Zwart, Sara R.; Mehta, Satish; Uchakin, Peter; Quiriarte, Heather A.; Pierson, Duane; Sams, Clarence F.; Smith, Scott M.

2013-01-01

Background: Aspects of immune system dysregulation associated with long-duration spaceflight have yet to be fully characterized, and may represent a clinical risk to crewmembers during deep space missions. Plasma cytokine concentration may serve as an indicator of in vivo physiological changes or immune system mobilization. Methods: The plasma concentrations of 22 cytokines were monitored in 28 astronauts during long-duration spaceflight onboard the International Space Station. Blood samples were collected three times before flight, 3-5 times during flight (depending on mission duration), at landing and 30 days post-landing. Analysis was performed by bead array immunoassay. Results: With few exceptions, minimal detectable mean plasma levels (<10 pg/ml) were observed at baseline (launch minus 180) for innate inflammatory cytokines or adaptive regulatory cytokines, however IL-1ra and several chemokines were constitutively present. An increase in the plasma concentration IL-8, IL-1ra, Tpo, CCL4, CXCL5, TNF(alpha), GM-CSF and VEGF was observed associated with spaceflight. Significant post-flight increases were observed for IL-6 and CCL2. No significant alterations were observed during or following spaceflight for adaptive/T-regulatory cytokines (IL-2, IFN(gamma), IL-17, IL4, IL-5, IL-10). Conclusions: This pattern of cytokine dysregulation suggests multiple physiological adaptations persist during flight, including inflammation, leukocyte recruitment, angiogenesis and thrombocyte regulation.

NASA 14 Day Undersea Missions: A Short-Duration Spaceflight Analog for Immune System Dysregulation

NASA Technical Reports Server (NTRS)

Crucian, B. E.; Stowe, R. P.; Mehta, S. K.; Quiriarte, H.; Pierson, D. L.; Sams, C. F.

2010-01-01

BACKGROUND Spaceflight-associated immune dysregulation (SAID) occurs during spaceflight and may represent specific clinical risks for exploration-class missions. An appropriate ground analog for spaceflight-associated immune dysregulation would offer a platform for ground-evaluation of various potential countermeasures. This study evaluated the NASA Undersea Mission Operations ( NEEMO ), consisting of 14 day undersea deployment at the Aquarius station, as an analog for SAID. Sixteen Aquanauts from missions NEEMO-12, 13 and 14 participated in the study. RESULTS Mid-mission alterations leukocyte distribution occurred, including granulocytosis and elevations in central-memory CD8+ T-cells. General T cell function was reduced during NEEMO missions in roughly 50% of subjects. Secreted cytokines profiles were evaluated following whole blood stimulation with CD3/CD28 (T cells) or LPS (monocytes). T cell production of IFNg, IL-5, IL-10, IL-2, TNFa and IL-6 were all reduced before and during the mission. Conversely, monocyte production of TNFa, IL-10, IL-6, IL-1b and IL-8 were elevated during mission, moreso at the MD-14 timepoint. Antibodies to Epstein-Barr virus (EBV) viral capsid antigen and early antigen were increased in approximately 40% of the subjects. Changes in EBV tetramer-positive CD8+ T-cells exhibited a variable pattern. Antibodies against Cytomegalovirus (CMV) were marginally increased during the mission. Herpesvirus reactivation was determined by PCR. EBV viral load was generally elevated at L-6. Higher levels of salivary EBV were found during the NEEMO mission than before and after as well as than the healthy controls. No VZV or CMV was found in any pre, during and after NEEMO mission or control samples. Plasma cortisol was elevated at L-6. CONCLUSION Unfortunately, L-6 may be too near to mission start to be an appropriate baseline measurement. The general immune changes in leukocyte distribution, T cell function, cytokine production, virus specific immunity and viral reactivation are similar to those observed during or following spaceflight. The NEEMO platform may thus have utility for short-duration, ground-based spaceflight-immune research, such as investigations of mechanism or countermeasures validation.

The ESA-NASA 'CHOICE' Study: Winterover at Concordia Station, Interior Antarctica, as an Analog for Spaceflight-Associated Immune Dysregu1ation

NASA Technical Reports Server (NTRS)

Crucian, Brian E,; Feuerecker, M.; Salam, A. P.; Rybka, A.; Stowe, R. P.; Morrels, M.; Mehta, S. K.; Quiriarte, H.; Quintens, Roel; Thieme, U.;

The role of cytokines in immune changes induced by spaceflight

NASA Technical Reports Server (NTRS)

Sonnenfeld, G.; Miller, E. S.

1993-01-01

It has become apparent that spaceflight alters many immune responses. Among the regulatory components of the immune response that have been shown to be affected by spaceflight is the cytokine network. Spaceflight, as well as model systems of spaceflight, have been shown to affect the production and action of various cytokines including interferons, interleukins, colony stimulating factors, and tumor necrosis factors. These changes have been shown not to involve a general shutdown of the cytokine network but, rather, to involve selective alterations of specific cytokine functions by spaceflight. The full breadth of changes in cytokines induced by spaceflight, as well as mechanisms, duration, adaptation, reversibility, and significance to resistance to infection and neoplastic diseases, remains to be established.

NASA HRP Immunology Discipline - Use of Terrestrial Analogs

NASA Technical Reports Server (NTRS)

Crucian, Brian

2014-01-01

Due to the cost and operational constraints, as well as technical implementation limitations, it is desirous to perform relevant space physiology investigations first in terrestrial 'space analogs'. This is particularly true for initial investigations, which may then provide appropriate focus for subsequent flight investigations, or for mechanistic investigations that simply cannot be performed during spaceflight. Appropriate analog choice is extremely important. There are a wide variety of terrestrial space analogs, each relevant to a particular physiological discipline (or disciplines) and each with a particular fidelity (or lack thereof) to spaceflight, and each with unique operational constraints. The HRP Immunology Discipline is tasked with managing the HRP Risk concerning clinical risk for Astronaut crews related to spaceflight-associated immune dysregulation. Such dysregulation has been documented to occur during spaceflight, and found to persist for the duration of a 6-month ISS mission. Studies continue to characterize the onorbit phenomenon, but it generally consists of diminished immunocyte function, dysregulated cytokine profiles, and persistent herpesvirus reactivation. Causes are thought to synergistically include microgravity, psychological or physiological stress, radiation, and/or circadian misalignment. An appropriate terrestrial analog for immune dysregulation would replicate as many of these influences as possible. Such analogs may include clinostat or bioreactor cell culture (microgravity), hindlimb suspension (stress, fluid shifts, hypokinesis), or human deployment to remote or extreme environments (isolation, stress, circadian). Also, the laboratory setting may be used as an analog, or to augment analogs, such as sleep deprivation/misalignment or human centrifugation to replicate gravitational stress. As an appropriate example of a NASA Disciplines use of Terrestrial space analogs, this talk will discuss spaceflight associated immune dysregulation, terrestrial immune analogs, and recent analog investigations.

Immune System Dysregulation, Viral Reactivation and Stress During Short-Duration Spaceflight

NASA Technical Reports Server (NTRS)

Pierson, Duane; Sams, Clarence; Crucian, Brian; Mehta, Satish; Stowe, Raymond; Uchakin, Peter; Quiriarte, Heather

2010-01-01

The objective of this NASA Short-Duration Bioastronautics Investigation (SDBI) was to assess spaceflight-associated immune dysregulation. Many previous studies have investigated this phenomenon post-flight, and found altered distribution and function of the peripheral leukocyte populations. Alterations in cytokine production profiles have also been reported. Unfortunately, post-flight data may be altered by the stress associated with high-G re-entry and readaptation to unit gravity following deconditioning. Therefore, the current study collected blood and saliva samples from crewmembers immediately before landing, and returned those samples to Earth for terrestrial analysis. Assays include peripheral comprehensive immunophenotype, T cell function, cytokine profiles, viral-specific immunity, latent viral reactivation (EBV, CMV, VZV), and stress hormone measurements. A total of 18 short duration crewmembers completed the study and the final data will be presented.

Changes of Cytokines during a Spaceflight Analog - a 45-Day Head-Down Bed Rest

PubMed Central

Zhang, Shusong; Pang, Xuewen; Liu, Hongju; Li, Li; Sun, Xiuyuan; Zhang, Yu; Wu, Hounan; Chen, Xiaoping; Ge, Qing

2013-01-01

Spaceflight is associated with deregulation in the immune system. Head-down bed rest (HDBR) at -6° is believed to be the most practical model for examining multi-system responses to microgravity in humans during spaceflight. In the present study, a 45-day HDBR was performed to investigate the alterations in human immune cell distributions and their functions in response to various stimuli. The effect of countermeasure, Rhodiola rosea (RR) treatment, was also examined. A significant decrease of interferon-γ (IFN-γ) and interleukin-17 (IL-17) productions by activated T cells, increase of IL-1β and IL-18 by activated B and myeloid cells were observed during HDBR. The upregulation of serum cortisol was correlated with the changes of IL-1 family cytokines. In addition, a significant increase of memory T and B cell and regulatory T cells (Treg) were also detected. The uptake of RR further decreased IFN-γ level and slowed down the upregulation of IL-1 family cytokines. These data suggest that for prolonged HDBR and spaceflight, the decreased protective T cell immunity and enhanced proinflammatory cytokines should be closely monitored. The treatment with RR may play an important role in suppressing proinflammatory cytokines but not in boosting protective T cell immunity. PMID:24143230

Toll Mediated Infection Response Is Altered by Gravity and Spaceflight in Drosophila

PubMed Central

Taylor, Katherine; Kleinhesselink, Kurt; George, Michael D.; Morgan, Rachel; Smallwood, Tangi; Hammonds, Ann S.; Fuller, Patrick M.; Saelao, Perot; Alley, Jeff; Gibbs, Allen G.; Hoshizaki, Deborah K.; von Kalm, Laurence; Fuller, Charles A.; Beckingham, Kathleen M.; Kimbrell, Deborah A.

2014-01-01

Space travel presents unlimited opportunities for exploration and discovery, but requires better understanding of the biological consequences of long-term exposure to spaceflight. Immune function in particular is relevant for space travel. Human immune responses are weakened in space, with increased vulnerability to opportunistic infections and immune-related conditions. In addition, microorganisms can become more virulent in space, causing further challenges to health. To understand these issues better and to contribute to design of effective countermeasures, we used the Drosophila model of innate immunity to study immune responses in both hypergravity and spaceflight. Focusing on infections mediated through the conserved Toll and Imd signaling pathways, we found that hypergravity improves resistance to Toll-mediated fungal infections except in a known gravitaxis mutant of the yuri gagarin gene. These results led to the first spaceflight project on Drosophila immunity, in which flies that developed to adulthood in microgravity were assessed for immune responses by transcription profiling on return to Earth. Spaceflight alone altered transcription, producing activation of the heat shock stress system. Space flies subsequently infected by fungus failed to activate the Toll pathway. In contrast, bacterial infection produced normal activation of the Imd pathway. We speculate on possible linkage between functional Toll signaling and the heat shock chaperone system. Our major findings are that hypergravity and spaceflight have opposing effects, and that spaceflight produces stress-related transcriptional responses and results in a specific inability to mount a Toll-mediated infection response. PMID:24475130

Immune changes in test animals during spaceflight

NASA Technical Reports Server (NTRS)

Lesnyak, A. T.; Sonnenfeld, G.; Rykova, M. P.; Meshkov, D. O.; Mastro, A.; Konstantinova, I.

1993-01-01

Over the past two decades, it has become apparent that changes in immune parameters occur in cosmonauts and astronauts after spaceflight. Therefore, interest has been generated in the use of animal surrogates to better understand the nature and extent of these changes, the mechanism of these changes, and to allow the possible development of countermeasures. Among the changes noted in animals after spaceflight are alterations in lymphocytic blastogenesis, cytokine function, natural killer cell activity, and colony-stimulating factors. The nature and significance of spaceflight-induced changes in immune responses will be the focus of this review.

The Integrated Impact of Diet On Human Immune Response, the Gut Microbiota, and Nutritional Status During Adaptation to a Spaceflight Analog

NASA Technical Reports Server (NTRS)

Douglas, G. L.; Zwart, S. R.; Young, M.; Kloeris, V.; Crucian, B.; Smith, S. M.; Lorenzi, H.

2017-01-01

Spaceflight impacts human physiology, including well documented immune system dysregulation. Diet, immune function, and the microbiome are interlinked, but diet is the only one of these factors that we have the ability to easily, and significantly, alter on Earth or during flight. As we understand dietary impacts on physiology more thoroughly, we may then improve the spaceflight diet to improve crew health and potentially reduce flight-associated physiological alterations. It is expected that increasing the consumption of fruits and vegetables and bioactive compounds (e.g.,omega-3 fatty acids, lycopene, flavonoids) and therefore enhancing overall nutritional intake from the nominal shelf-stable, fully-processed space food system could serve as a countermeasure to improve human immunological profiles, the taxonomic profile of the gut microbiota, and nutritional status, especially where currently dysregulated during spaceflight. This interdisciplinary study will determine the effect of the current shelf-stable spaceflight diet compared to an "enhanced" shelf-stable spaceflight diet (25% more foods rich in omega-3 fatty acids, lycopene, flavonoids, fruits, and vegetables). The NASA Human Exploration Research Analog (HERA) 2017 missions, consisting of closed chamber confinement, realistic mission simulation, in a high-fidelity mock space vehicle, will serve as a platform to replicate mission stressors and the dysregulated physiology observed in astronauts. Biosampling of crew members will occur at selected intervals, with complete dietary tracking. Outcome measures will include immune markers (e.g., peripheral leukocyte distribution, inflammatory cytokine profiles, T cell function), the taxonomic and metatranscriptomic profile of the gut microbiome, and nutritional status biomarkers and metabolites. Data collection will also include complete dietary tracking. Statistical evaluations will determine physiological and biochemical shifts in relation to nutrient in take and study phase. Beneficial improvements will provide evidence of the impact of diet on crew health and adaptation to this spaceflight analog, and will aid in the design and development of more-efficient targeted dietary interventions.

Alterations in adaptive immunity persist during long-duration spaceflight.

PubMed

Crucian, Brian; Stowe, Raymond P; Mehta, Satish; Quiriarte, Heather; Pierson, Duane; Sams, Clarence

2015-01-01

It is currently unknown whether immune system alterations persist during long-duration spaceflight. In this study various adaptive immune parameters were assessed in astronauts at three intervals during 6-month spaceflight on board the International Space Station (ISS). To assess phenotypic and functional immune system alterations in astronauts participating in 6-month orbital spaceflight. Blood was collected before, during, and after flight from 23 astronauts participating in 6-month ISS expeditions. In-flight samples were returned to Earth within 48 h of collection for immediate analysis. Assays included peripheral leukocyte distribution, T-cell function, virus-specific immunity, and mitogen-stimulated cytokine production profiles. Redistribution of leukocyte subsets occurred during flight, including an elevated white blood cell (WBC) count and alterations in CD8 + T-cell maturation. A reduction in general T-cell function (both CD4 + and CD8 + ) persisted for the duration of the 6-month spaceflights, with differential responses between mitogens suggesting an activation threshold shift. The percentage of CD4 + T cells capable of producing IL-2 was depressed after landing. Significant reductions in mitogen-stimulated production of IFNγ, IL-10, IL-5, TNFα, and IL-6 persisted during spaceflight. Following lipopolysaccharide (LPS) stimulation, production of IL-10 was reduced, whereas IL-8 production was increased during flight. The data indicated that immune alterations persist during long-duration spaceflight. This phenomenon, in the absence of appropriate countermeasures, has the potential to increase specific clinical risks for crewmembers during exploration-class deep space missions.

Alterations in adaptive immunity persist during long-duration spaceflight

PubMed Central

Crucian, Brian; Stowe, Raymond P; Mehta, Satish; Quiriarte, Heather; Pierson, Duane; Sams, Clarence

2015-01-01

Background: It is currently unknown whether immune system alterations persist during long-duration spaceflight. In this study various adaptive immune parameters were assessed in astronauts at three intervals during 6-month spaceflight on board the International Space Station (ISS). AIMS: To assess phenotypic and functional immune system alterations in astronauts participating in 6-month orbital spaceflight. Methods: Blood was collected before, during, and after flight from 23 astronauts participating in 6-month ISS expeditions. In-flight samples were returned to Earth within 48 h of collection for immediate analysis. Assays included peripheral leukocyte distribution, T-cell function, virus-specific immunity, and mitogen-stimulated cytokine production profiles. Results: Redistribution of leukocyte subsets occurred during flight, including an elevated white blood cell (WBC) count and alterations in CD8+ T-cell maturation. A reduction in general T-cell function (both CD4+ and CD8+) persisted for the duration of the 6-month spaceflights, with differential responses between mitogens suggesting an activation threshold shift. The percentage of CD4+ T cells capable of producing IL-2 was depressed after landing. Significant reductions in mitogen-stimulated production of IFNγ, IL-10, IL-5, TNFα, and IL-6 persisted during spaceflight. Following lipopolysaccharide (LPS) stimulation, production of IL-10 was reduced, whereas IL-8 production was increased during flight. Conclusions: The data indicated that immune alterations persist during long-duration spaceflight. This phenomenon, in the absence of appropriate countermeasures, has the potential to increase specific clinical risks for crewmembers during exploration-class deep space missions. PMID:28725716

Spaceflight Influences both Mucosal and Peripheral Cytokine Production in PTN-Tg and Wild Type Mice

PubMed Central

Liu, Yi; Kalmokoff, Martin; Brooks, Stephen P. J.; Green-Johnson, Julia M.

2013-01-01

Spaceflight is associated with several health issues including diminished immune efficiency. Effects of long-term spaceflight on selected immune parameters of wild type (Wt) and transgenic mice over-expressing pleiotrophin under the human bone-specific osteocalcin promoter (PTN-Tg) were examined using the novel Mouse Drawer System (MDS) aboard the International Space Station (ISS) over a 91 day period. Effects of this long duration flight on PTN-Tg and Wt mice were determined in comparison to ground controls and vivarium-housed PTN-Tg and Wt mice. Levels of interleukin-2 (IL-2) and transforming growth factor-beta1 (TGF-β1) were measured in mucosal and systemic tissues of Wt and PTN-Tg mice. Colonic contents were also analyzed to assess potential effects on the gut microbiota, although no firm conclusions could be made due to constraints imposed by the MDS payload and the time of sampling. Spaceflight-associated differences were observed in colonic tissue and systemic lymph node levels of IL-2 and TGF-β1 relative to ground controls. Total colonic TGF-β1 levels were lower in Wt and PTN-Tg flight mice in comparison to ground controls. The Wt flight mouse had lower levels of IL-2 and TGF-β1 compared to the Wt ground control in both the inguinal and brachial lymph nodes, however this pattern was not consistently observed in PTN-Tg mice. Vivarium-housed Wt controls had higher levels of active TGF-β1 and IL-2 in inguinal lymph nodes relative to PTN-Tg mice. The results of this study suggest compartmentalized effects of spaceflight and on immune parameters in mice. PMID:23874826

Immunomodulatory properties of carbon nanotubes are able to compensate immune function dysregulation caused by microgravity conditions

NASA Astrophysics Data System (ADS)

Crescio, Claudia; Orecchioni, Marco; Ménard-Moyon, Cécilia; Sgarrella, Francesco; Pippia, Proto; Manetti, Roberto; Bianco, Alberto; Delogu, Lucia Gemma

2014-07-01

Spaceflights lead to dysregulation of the immune cell functionality affecting the expression of activation markers and cytokine production. Short oxidized multi-walled carbon nanotubes functionalized by 1,3-dipolar cycloaddition have been reported to activate immune cells. In this Communication we have performed surface marker assays and multiplex ELISA on primary monocytes and T cells under microgravity. We have discovered that carbon nanotubes, through their immunostimulatory properties, are able to fight spaceflight immune system dysregulations.Spaceflights lead to dysregulation of the immune cell functionality affecting the expression of activation markers and cytokine production. Short oxidized multi-walled carbon nanotubes functionalized by 1,3-dipolar cycloaddition have been reported to activate immune cells. In this Communication we have performed surface marker assays and multiplex ELISA on primary monocytes and T cells under microgravity. We have discovered that carbon nanotubes, through their immunostimulatory properties, are able to fight spaceflight immune system dysregulations. Electronic supplementary information (ESI) available: Experimental section, structures of f-MWCNTs and uptake by human primary immune cells. See DOI: 10.1039/c4nr02711f

Immune System Dysregulation and Latent Herpesvirus Reactivation During Winterover at Concordia Station, Dome C, Antarctica

NASA Technical Reports Server (NTRS)

Crucian, B. E.; Feuerecker, M.; Salam, A. P.; Rybka, A.; Stowe, R. P.; Morrels, M.; Meta, S. K.; Quiriarte, H.; Quintens, Roel; Thieme, U.;

Early Immune Function and Duration of Organ Dysfunction in Critically Ill Septic Children.

PubMed

Muszynski, Jennifer A; Nofziger, Ryan; Moore-Clingenpeel, Melissa; Greathouse, Kristin; Anglim, Larissa; Steele, Lisa; Hensley, Josey; Hanson-Huber, Lisa; Nateri, Jyotsna; Ramilo, Octavio; Hall, Mark W

2018-02-22

Late immune suppression is associated with nosocomial infection and mortality in septic adults and children. Relationships between early immune suppression and outcomes in septic children remain unclear. Prospective observational study to test the hypothesis that early innate and adaptive immune suppression are associated with longer duration of organ dysfunction in children with severe sepsis/septic shock. Methods, Measurements and Main Results: Children aged < 18 years meeting consensus criteria for severe sepsis or septic shock were sampled within 48 hours of sepsis onset. Healthy controls were sampled once. Innate immune function was quantified by whole blood ex vivo lipopolysaccharide-induced TNFα production capacity. Adaptive immune function was quantified by ex vivo phytohemagglutinin-induced IFNγ production capacity. 102 septic children and 35 healthy children were enrolled. Compared to healthy children, septic children demonstrated lower LPS-induced TNFα production (p < 0.0001) and lower PHA-induced IFNγ production (p<0.0001). Among septic children, early innate and adaptive immune suppression were associated with greater number of days with multiple organ dysfunction (MODS) and greater number of days with any organ dysfunction. On multivariable analyses, early innate immune suppression remained independently associated with increased MODS days [aRR 1.2 (1.03, 1.5)] and organ dysfunction days [aRR 1.2 (1.1, 1.3)]. Critically ill children with severe sepsis or septic shock demonstrate early innate and adaptive immune suppression. Early suppression of both innate and adaptive immunity are associated with longer duration of organ dysfunction and may be useful markers to guide investigations of immunomodulatory therapies in septic children.

Cardiac Atrophy and Diastolic Dysfunction During and After Long Duration Spaceflight: Functional Consequences for Orthostatic Intolerance, Exercise Capability and Risk for Cardiac Arrhythmias

NASA Technical Reports Server (NTRS)

Levine, Benjamin D.; Bungo, Michael W.; Platts, Steven H.; Hamilton, Douglas R.; Johnston, Smith L.

2009-01-01

Cardiac Atrophy and Diastolic Dysfunction During and After Long Duration Spaceflight: Functional Consequences for Orthostatic Intolerance, Exercise Capability and Risk for Cardiac Arrhythmias (Integrated Cardiovascular) will quantify the extent of long-duration space flightassociated cardiac atrophy (deterioration) on the International Space Station crewmembers.

The role of psychoneuroendocrine factors on spaceflight-induced immunological alterations

NASA Technical Reports Server (NTRS)

Meehan, R.; Whitson, P.; Sams, C.

1993-01-01

This paper summarizes previous in-flight infections and novel conditions of spaceflight that may suppress immune function. Granulocytosis, monocytosis, and lymphopenia are routinely observed following short duration orbital flights. Subtle changes within the monocyte and T cell populations can also be noted by flow cytometric analysis. The similarity between the immunological changes observed after spaceflight and other diverse environmental stressors suggest that most of these alterations may be neuroendocrine-mediated. Available data support the hypothesis that spaceflight and other environmental stressors modulate normal immune regulation via stress hormones, other than exclusively glucocorticoids. It will be essential to simultaneously collect in-flight endocrine, immunologic, and infectious illness data to determine the clinical significance of these results. Additional research that delineates the neuroendocrine mechanisms of stress-induced changes in normal immune regulation will allow clinicians in the future to initiate prophylactic immunomodulator therapy to restore immune competence altered by the stress of long-duration spaceflight and therefore reduce morbidity from infectious illness, autoimmune disease, or malignancy.

The ESA-NASA CHOICE Study: Winterover at Concordia Station, Interior Antarctica, A Potential Analog for Spaceflight-Associated Immune Dysregulation

NASA Technical Reports Server (NTRS)

Crucian, B. E.; Stowe, R. P.; Mehta, S. K.; Quiriarte, H.; Pierson, D L.; Sams, C. F.

2010-01-01

For ground-based space physiological research, the choice of terrestrial analog must carefully match the system of interest. Antarctica winter-over at the European Concordia Station is potentially a superior ground-analog for spaceflight-associated immune dysregulation (SAID). Concordia missions consist of prolonged durations in an extreme/dangerous environment, station-based habitation, isolation, disrupted circadian rhythms and international crews. The ESA-NASA CHOICE study assesses innate and adaptive immunity, viral reactivation and stress factors during Concordia winterover deployment. Initial data obtained from the first study deployment (2009 mission; 'n' of 6) will be presented, and logistical challenges regarding analog usage for biological studies will also be discussed. The total WBC increased, and alterations in some peripheral leukocyte populations were observed during winterover at Concordia Station. Percentages of lymphocytes and monocytes increased, and levels of senescent CD8+ T cells were increased during deployment. Transient increases in constitutively activated T cell subsets were observed, at mission time points associated with endemic disease outbreaks. T cell function (early blastogenesis response) was increased near the entry/exit deployment phases, and production of most measured cytokines increased during deployment. Salivary cortisol demonstrated high variability during winterover, but was generally increased. A 2-point circadian rhythm of cortisol measurement (morning/evening) was unaltered during winterover. Perceived stress was mildly elevated during winterover. Other measures, including in-vitro DTH assessment, viral specific T cell number/function and latent herpesvirus reactivation have not yet been completed for the 2009 winterover subjects. Based on the preliminary data, alterations in immune cell distribution and function appear to persist during Antarctic winterover at Concordia Station. Some of these changes are similar to those observed in Astronauts, either during or immediately following spaceflight. Based on the initial immune data and environmental conditions, Concordia winterover may be an appropriate analog for some flight-associated immune changes.

Spaceflight and Simulated Microgravity Increases Virulence of the Known Bacterial Pathogen S. Marcescens

NASA Technical Reports Server (NTRS)

Clemens-Grisham, Rachel Andrea; Bhattacharya, Sharmila; Wade, William

2016-01-01

After spaceflight, the number of immune cells is reduced in humans. In other research models, including Drosophila, not only is there a reduction in the number of plasmatocytes, but expression of immune-related genes is also changed after spaceflight. These observations suggest that the immune system is compromised after exposure to microgravity. It has also been reported that there is a change in virulence of some bacterial pathogens after spaceflight. We recently observed that samples of gram-negative S. marcescens retrieved from spaceflight is more virulent than ground controls, as determined by reduced survival and increased bacterial growth in the host. We were able to repeat this finding of increased virulence after exposure to simulated microgravity using the rotating wall vessel, a ground based analog to microgravity. With the ground and spaceflight samples, we looked at involvement of the Toll and Imd pathways in the Drosophila host in fighting infection by ground and spaceflight samples. We observed that Imd-pathway mutants were more susceptible to infection by the ground bacterial samples, which aligns with the known role of this pathway in fighting infections by gram-negative bacteria. When the Imd-pathway mutants were infected with the spaceflight sample, however, they exhibited the same susceptibility as seen with the ground control bacteria. Interestingly, all mutant flies show the same susceptibility to the spaceflight bacterial sample as do wild type flies. This suggests that neither humoral immunity pathway is effectively able to counter the increased pathogenicity of the space-flown S. marcescens bacteria.

Determination of Roles of Microgravity and Ionizing Radiation on the Reactivation of Epstein-Barr Virus In Vitro

NASA Technical Reports Server (NTRS)

Mehta, Satish K; Renner, Ashlie; Stowe, Raymond; Bloom, David; Pierson, Duane

2015-01-01

Astronauts experience symptomatic and asymptomatic herpes virus reactivation during spaceflight. We have shown increases in reactivation of Epstein-Barr virus (EBV), cytomegalovirus (CMV) and varicella zoster virus (VZV) and shedding in body fluids (saliva and urine) in astronauts during space travel. Alterations in immunity, increased stress hormone levels, microgravity, increased radiation, and other conditions unique to spaceflight may promote reactivation of latent herpes viruses. Unique mechanico-physico forces associated with spaceflight can have profound effects on cellular function, especially immune cells. In space flight analog studies such as Antarctica, bed rest studies, and NASA's undersea habitat (Aquarius), reactivation of these viruses occurred, but to a lesser extent than spaceflight. Spaceflight analogs model some spaceflight factors, but none of the analogs recreates all factors experienced in space. Most notably, microgravity and radiation are not included in many analogs. Stress, processed through the HPA axis and SAM systems, induces viral reactivation. However, the respective roles of microgravity and increased space radiation levels or if any synergy exists are not known. Therefore, we studied the effect of modeled space radiation and/or microgravity, independent of the immune system on the changes in cellular gene expression that results in viral (EBV) reactivation. The effects of modeled microgravity and low shear on EBV replication and cellular and EBV gene expression were studied in human B-lymphocyte cell cultures. Latently infected B-lymphocytes were propagated in the rotating wall bioreactor and irradiated with the various dosages of gamma irradiation. At specific time intervals following exposure to modeled microgravity, the cells and supernatant were harvested and reactivation of EBV were assessed by measuring EBV and gene expression, DNA methylation, and infectious virus production.

Immune dysfunction in cirrhosis.

PubMed

Sipeki, Nora; Antal-Szalmas, Peter; Lakatos, Peter L; Papp, Maria

2014-03-14

Innate and adaptive immune dysfunction, also referred to as cirrhosis-associated immune dysfunction syndrome, is a major component of cirrhosis, and plays a pivotal role in the pathogenesis of both the acute and chronic worsening of liver function. During the evolution of the disease, acute decompensation events associated with organ failure(s), so-called acute-on chronic liver failure, and chronic decompensation with progression of liver fibrosis and also development of disease specific complications, comprise distinct clinical entities with different immunopathology mechanisms. Enhanced bacterial translocation associated with systemic endotoxemia and increased occurrence of systemic bacterial infections have substantial impacts on both clinical situations. Acute and chronic exposure to bacteria and/or their products, however, can result in variable clinical consequences. The immune status of patients is not constant during the illness; consequently, alterations of the balance between pro- and anti-inflammatory processes result in very different dynamic courses. In this review we give a detailed overview of acquired immune dysfunction and its consequences for cirrhosis. We demonstrate the substantial influence of inherited innate immune dysfunction on acute and chronic inflammatory processes in cirrhosis caused by the pre-existing acquired immune dysfunction with limited compensatory mechanisms. Moreover, we highlight the current facts and future perspectives of how the assessment of immune dysfunction can assist clinicians in everyday practical decision-making when establishing treatment and care strategies for the patients with end-stage liver disease. Early and efficient recognition of inappropriate performance of the immune system is essential for overcoming complications, delaying progression and reducing mortality.

Immune dysfunction in cirrhosis

PubMed Central

Sipeki, Nora; Antal-Szalmas, Peter; Lakatos, Peter L; Papp, Maria

2014-01-01

Innate and adaptive immune dysfunction, also referred to as cirrhosis-associated immune dysfunction syndrome, is a major component of cirrhosis, and plays a pivotal role in the pathogenesis of both the acute and chronic worsening of liver function. During the evolution of the disease, acute decompensation events associated with organ failure(s), so-called acute-on chronic liver failure, and chronic decompensation with progression of liver fibrosis and also development of disease specific complications, comprise distinct clinical entities with different immunopathology mechanisms. Enhanced bacterial translocation associated with systemic endotoxemia and increased occurrence of systemic bacterial infections have substantial impacts on both clinical situations. Acute and chronic exposure to bacteria and/or their products, however, can result in variable clinical consequences. The immune status of patients is not constant during the illness; consequently, alterations of the balance between pro- and anti-inflammatory processes result in very different dynamic courses. In this review we give a detailed overview of acquired immune dysfunction and its consequences for cirrhosis. We demonstrate the substantial influence of inherited innate immune dysfunction on acute and chronic inflammatory processes in cirrhosis caused by the pre-existing acquired immune dysfunction with limited compensatory mechanisms. Moreover, we highlight the current facts and future perspectives of how the assessment of immune dysfunction can assist clinicians in everyday practical decision-making when establishing treatment and care strategies for the patients with end-stage liver disease. Early and efficient recognition of inappropriate performance of the immune system is essential for overcoming complications, delaying progression and reducing mortality. PMID:24627592

The Integrated Impact of Diet on Human Immune Response, the Gut Microbiota, and Nutritional Status During Adaptation to a Spaceflight Analog

NASA Technical Reports Server (NTRS)

Douglas, G. L.; Zwart, S. R.; Young, M.; Kloeris, V.; Crucian, B.; Smith, S. M.; Lorenzi, H.

2018-01-01

Spaceflight impacts human physiology, including well documented immune system dysregulation. Diet, immune function, and the microbiome are interlinked, but diet is the only one of these factors that we have the ability to easily, and significantly, alter on Earth or during flight. As we understand dietary impacts on physiology more thoroughly, we may then improve the spaceflight diet to improve crew health and potentially reduce spaceflight-associated physiological alterations. It is expected that increasing the consumption of fruits and vegetables and bioactive compounds (e.g., omega-3 fatty acids, lycopene, flavonoids) and therefore enhancing overall nutritional intake from the nominal shelf-stable, fully-processed space food system could serve as a countermeasure to improve human immunological profiles, the taxonomic profile of the gut microbiota, and nutritional status, especially where currently dysregulated during spaceflight. This interdisciplinary study will determine the effect of the current shelf-stable spaceflight diet compared to an "enhanced" shelf-stable spaceflight diet (25% more foods rich in omega-3 fatty acids, lycopene, flavonoids, and more fruits, and vegetables in general). The NASA Human Exploration Research Analog (HERA) 2017 missions, consisting of four 45-day missions with closed chamber confinement and realistic mission simulation in a high-fidelity mock space vehicle, will serve as a platform to replicate mission stressors and the effects on crew biochemistry, immunology, and the gut microbiome. Bio sampling of crewmembers is scheduled for selected intervals pre- and in-mission. Data collection also includes dietary intake recording. Outcome measures will include immune markers (e.g., peripheral leukocyte distribution, inflammatory cytokine profiles, T cell function), the taxonomic and metatranscriptomic profile of the gut microbiome, and nutritional status biomarkers and metabolites. Statistical evaluations will determine physiological and biochemical shifts in relation to nutrient intake and study phase. To date, sample collection has been completed for 2 crewmembers from the first mission, aka Campaign 4 Mission 1. Mission 2 was terminated after 22 days due to effects of Hurricane Harvey, and sample collection was not completed. Sample collection will continue for Campaign 4 Mission 3 and 4 prior to comprehensive sample analysis. Beneficial improvements will provide evidence of the impact of diet on crew health and adaptation to this spaceflight analog, and will aid in the design and development of more-efficient targeted dietary interventions for exploration missions.

Cardiovascular Deconditioning

NASA Technical Reports Server (NTRS)

Charles, John B.; Fritsch-Yelle, Janice M.; Whitson, Peggy A.; Wood, Margie L.; Brown, Troy E.; Fortner, G. William

1999-01-01

Spaceflight causes adaptive changes in cardiovascular function that may deleteriously affect crew health and safety. Over the last three decades, symptoms of cardiovascular changes have ranged from postflight orthostatic tachycardia and decreased exercise capacity to serious cardiac rhythm disturbances during extravehicular activities (EVA). The most documented symptom of cardiovascular dysfunction, postflight orthostatic intolerance, has affected a significant percentage of U.S. Space Shuttle astronauts. Problems of cardiovascular dysfunction associated with spaceflight are a concern to NASA. This has been particularly true during Shuttle flights where the primary concern is the crew's physical health, including the pilot's ability to land the Orbiter, and the crew's ability to quickly egress and move to safety should a dangerous condition arise. The study of astronauts during Shuttle activities is inherently more difficult than most human research. Consequently, sample sizes have been small and results have lacked consistency. Before the Extended Duration Orbiter Medical Project (EDOMP), there was a lack of normative data on changes in cardiovascular parameters during and after spaceflight. The EDOMP for the first time allowed studies on a large enough number of subjects to overcome some of these problems. There were three primary goals of the Cardiovascular EDOMP studies. The first was to establish, through descriptive studies, a normative data base of cardiovascular changes attributable to spaceflight. The second goal was to determine mechanisms of cardiovascular changes resulting from spaceflight (particularly orthostatic hypotension and cardiac rhythm disturbances). The third was to evaluate possible countermeasures. The Cardiovascular EDOMP studies involved parallel descriptive, mechanistic, and countermeasure evaluations.

Overview of spaceflight immunology studies

NASA Technical Reports Server (NTRS)

Taylor, G. R.

1993-01-01

The effects of spaceflight and analogues of spaceflight are discussed here and in nine accompanying articles. In this summary we present spaceflight studies with human subjects, animal subjects, and cell cultures and we review ground-based systems used to model the observed effects of spaceflight on the immune system. Human paradigms include bed rest, academic or psychological stress, physical stress, hypobaric or high altitude stress, and confinement. Animal models include antiorthostatic and orthostatic suspension, hypobarism, and confinement. The ten manuscripts in this collection were selected to provide a summary that should give the reader an overview of the various activities of spaceflight immunology researchers throughout the history of space travel. This manuscript identifies the major contributors to the study of spaceflight immunology, explains what types of studies have been conducted, and how they have changed over the years. Also presented is a discussion of the unusual limitations associated with spaceflight research and the efforts to develop appropriate ground-based surrogate model systems. Specific details, data, and mechanistic speculations will be held to a minimum, because they will be discussed in depth in the other articles in the collection.

Changes in the immune system during and after spaceflight

NASA Technical Reports Server (NTRS)

Taylor, G. R.; Konstantinova, I.; Sonnenfeld, G.; Jennings, R.

1997-01-01

The results of immunological analyses before, during and after spaceflight, have established the fact that spaceflight can result in a blunting of the immune mechanisms of human crew members and animal test species. There is some evidence that the immune function changes in short-term flights resemble those occurring after acute stress, while the changes during long-term flights resemble those caused by chronic stress. In addition, this blunting of the immune function occurs concomitant with a relative increase in potentially infectious microorganisms in the space cabin environment. This combination of events results in an increased probability of inflight infectious events. The realization of this probability has been shown to be partially negated by the judicious use of a preflight health stabilization program and other operational countermeasures. The continuation of these countermeasures, as well as microbial and immunological monitoring, are recommended for continued spaceflight safety.

Is spaceflight-induced immune dysfunction linked to systemic changes in metabolism?

PubMed Central

Mao, Xiao Wen; Bellinger, Denise L.; Jonscher, Karen R.; Stodieck, Louis S.; Ferguson, Virginia L.; Bateman, Ted A.; Mohney, Robert P.; Gridley, Daila S.

2017-01-01

The Space Shuttle Atlantis launched on its final mission (STS-135) on July 8, 2011. After just under 13 days, the shuttle landed safely at Kennedy Space Center (KSC) for the last time. Female C57BL/6J mice flew as part of the Commercial Biomedical Testing Module-3 (CBTM-3) payload. Ground controls were maintained at the KSC facility. Subsets of these mice were made available to investigators as part of NASA’s Bio-specimen Sharing Program (BSP). Our group characterized cell phenotype distributions and phagocytic function in the spleen, catecholamine and corticosterone levels in the adrenal glands, and transcriptomics/metabolomics in the liver. Despite decreases in most splenic leukocyte subsets, there were increases in reactive oxygen species (ROS)-related activity. Although there were increases noted in corticosterone levels in both the adrenals and liver, there were no significant changes in catecholamine levels. Furthermore, functional analysis of gene expression and metabolomic profiles suggest that the functional changes are not due to oxidative or psychological stress. Despite changes in gene expression patterns indicative of increases in phagocytic activity (e.g. endocytosis and formation of peroxisomes), there was no corresponding increase in genes related to ROS metabolism. In contrast, there were increases in expression profiles related to fatty acid oxidation with decreases in glycolysis-related profiles. Given the clear link between immune function and metabolism in many ground-based diseases, we propose a similar link may be involved in spaceflight-induced decrements in immune and metabolic function. PMID:28542224

Is spaceflight-induced immune dysfunction linked to systemic changes in metabolism?

PubMed

Pecaut, Michael J; Mao, Xiao Wen; Bellinger, Denise L; Jonscher, Karen R; Stodieck, Louis S; Ferguson, Virginia L; Bateman, Ted A; Mohney, Robert P; Gridley, Daila S

2017-01-01

The Space Shuttle Atlantis launched on its final mission (STS-135) on July 8, 2011. After just under 13 days, the shuttle landed safely at Kennedy Space Center (KSC) for the last time. Female C57BL/6J mice flew as part of the Commercial Biomedical Testing Module-3 (CBTM-3) payload. Ground controls were maintained at the KSC facility. Subsets of these mice were made available to investigators as part of NASA's Bio-specimen Sharing Program (BSP). Our group characterized cell phenotype distributions and phagocytic function in the spleen, catecholamine and corticosterone levels in the adrenal glands, and transcriptomics/metabolomics in the liver. Despite decreases in most splenic leukocyte subsets, there were increases in reactive oxygen species (ROS)-related activity. Although there were increases noted in corticosterone levels in both the adrenals and liver, there were no significant changes in catecholamine levels. Furthermore, functional analysis of gene expression and metabolomic profiles suggest that the functional changes are not due to oxidative or psychological stress. Despite changes in gene expression patterns indicative of increases in phagocytic activity (e.g. endocytosis and formation of peroxisomes), there was no corresponding increase in genes related to ROS metabolism. In contrast, there were increases in expression profiles related to fatty acid oxidation with decreases in glycolysis-related profiles. Given the clear link between immune function and metabolism in many ground-based diseases, we propose a similar link may be involved in spaceflight-induced decrements in immune and metabolic function.

Spaceflight and simulated microgravity cause a significant reduction of key gene expression in early T-cell activation

PubMed Central

Martinez, Emily M.; Yoshida, Miya C.; Candelario, Tara Lynne T.

2015-01-01

Healthy immune function depends on precise regulation of lymphocyte activation. During the National Aeronautics and Space Administration (NASA) Apollo and Shuttle eras, multiple spaceflight studies showed depressed lymphocyte activity under microgravity (μg) conditions. Scientists on the ground use two models of simulated μg (sμg): 1) the rotating wall vessel (RWV) and 2) the random positioning machine (RPM), to study the effects of altered gravity on cell function before advancing research to the true μg when spaceflight opportunities become available on the International Space Station (ISS). The objective of this study is to compare the effects of true μg and sμg on the expression of key early T-cell activation genes in mouse splenocytes from spaceflight and ground animals. For the first time, we compared all three conditions of microgravity spaceflight, RPM, and RWV during immune gene activation of Il2, Il2rα, Ifnγ, and Tagap; moreover, we confirm two new early T-cell activation genes, Iigp1 and Slamf1. Gene expression for all samples was analyzed using quantitative real-time PCR (qRT-PCR). Our results demonstrate significantly increased gene expression in activated ground samples with suppression of mouse immune function in spaceflight, RPM, and RWV samples. These findings indicate that sμg models provide an excellent test bed for scientists to develop baseline studies and augment true μg in spaceflight experiments. Ultimately, sμg and spaceflight studies in lymphocytes may provide insight into novel regulatory pathways, benefiting both future astronauts and those here on earth suffering from immune disorders. PMID:25568077

Spaceflight and simulated microgravity cause a significant reduction of key gene expression in early T-cell activation.

PubMed

Martinez, Emily M; Yoshida, Miya C; Candelario, Tara Lynne T; Hughes-Fulford, Millie

2015-03-15

Healthy immune function depends on precise regulation of lymphocyte activation. During the National Aeronautics and Space Administration (NASA) Apollo and Shuttle eras, multiple spaceflight studies showed depressed lymphocyte activity under microgravity (μg) conditions. Scientists on the ground use two models of simulated μg (sμg): 1) the rotating wall vessel (RWV) and 2) the random positioning machine (RPM), to study the effects of altered gravity on cell function before advancing research to the true μg when spaceflight opportunities become available on the International Space Station (ISS). The objective of this study is to compare the effects of true μg and sμg on the expression of key early T-cell activation genes in mouse splenocytes from spaceflight and ground animals. For the first time, we compared all three conditions of microgravity spaceflight, RPM, and RWV during immune gene activation of Il2, Il2rα, Ifnγ, and Tagap; moreover, we confirm two new early T-cell activation genes, Iigp1 and Slamf1. Gene expression for all samples was analyzed using quantitative real-time PCR (qRT-PCR). Our results demonstrate significantly increased gene expression in activated ground samples with suppression of mouse immune function in spaceflight, RPM, and RWV samples. These findings indicate that sμg models provide an excellent test bed for scientists to develop baseline studies and augment true μg in spaceflight experiments. Ultimately, sμg and spaceflight studies in lymphocytes may provide insight into novel regulatory pathways, benefiting both future astronauts and those here on earth suffering from immune disorders.

Spaceflight impairs antigen-specific tolerance induction in vivo and increases inflammatory cytokines.

PubMed

Chang, Tammy T; Spurlock, Sandra M; Candelario, Tara Lynne T; Grenon, S Marlene; Hughes-Fulford, Millie

2015-10-01

The health risks of a dysregulated immune response during spaceflight are important to understand as plans emerge for humans to embark on long-term space travel to Mars. In this first-of-its-kind study, we used adoptive transfer of T-cell receptor transgenic OT-II CD4 T cells to track an in vivo antigen-specific immune response that was induced during the course of spaceflight. Experimental mice destined for spaceflight and mice that remained on the ground received transferred OT-II cells and cognate peptide stimulation with ovalbumin (OVA) 323-339 plus the inflammatory adjuvant, monophosphoryl lipid A. Control mice in both flight and ground cohorts received monophosphoryl lipid A alone without additional OVA stimulation. Numbers of OT-II cells in flight mice treated with OVA were significantly increased by 2-fold compared with ground mice treated with OVA, suggesting that tolerance induction was impaired by spaceflight. Production of proinflammatory cytokines were significantly increased in flight compared with ground mice, including a 5-fold increase in IFN-γ and a 10-fold increase in IL-17. This study is the first to show that immune tolerance may be impaired in spaceflight, leading to excessive inflammatory responses. © FASEB.

Innate Immune Responses of Drosophila melanogaster Are Altered by Spaceflight

PubMed Central

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

Spaceflight Sensorimotor Analogs: Simulating Acute and Adaptive Effects

NASA Technical Reports Server (NTRS)

Taylor, Laura C.; Harm, Deborah L.; Kozlovskaya, Inessa; Reschke, Millard F.; Wood, Scott J.

2009-01-01

Adaptive changes in sensorimotor function during spaceflight are reflected by spatial disorientation, motion sickness, gaze destabilization and decrements in balance, locomotion and eye-hand coordination that occur during and following transitions between different gravitational states. The purpose of this study was to conduct a meta-synthesis of data from spaceflight analogs to evaluate their effectiveness in simulating adaptive changes in sensorimotor function. METHODS. The analogs under review were categorized as either acute analogs used to simulate performance decrements accompanied with transient changes, or adaptive analogs used to drive sensorimotor learning to altered sensory feedback. The effectiveness of each analog was evaluated in terms of mechanisms of action, magnitude and time course of observed deficits compared to spaceflight data, and the effects of amplitude and exposure duration. RESULTS. Parabolic flight has been used extensively to examine effects of acute variation in gravitational loads, ranging from hypergravity to microgravity. More recently, galvanic vestibular stimulation has been used to elicit acute postural, locomotor and gaze dysfunction by disrupting vestibular afferents. Patient populations, e.g., with bilateral vestibular loss or cerebellar dysfunction, have been proposed to model acute sensorimotor dysfunction. Early research sponsored by NASA involved living onboard rotating rooms, which appeared to approximate the time course of adaptation and post-exposure recovery observed in astronauts following spaceflight. Exposure to different bed-rest paradigms (6 deg head down, dry immersion) result in similar motor deficits to that observed following spaceflight. Shorter adaptive analogs have incorporated virtual reality environments, visual distortion paradigms, exposure to conflicting tilt-translation cues, and exposure to 3Gx centrifugation. As with spaceflight, there is considerable variability in responses to most of the analogs reviewed. DISCUSSION. A true ground-based flight analog for sensorimotor function is not feasible. A combination of flight analogs; however, can be used to selectively mimic different aspects of the spaceflight-induced sensorimotor performance decrements.

Spaceflight Activates Autophagy Programs and the Proteasome in Mouse Liver

PubMed Central

Blaber, Elizabeth A.; Pecaut, Michael J.

2017-01-01

Increased oxidative stress is an unavoidable consequence of exposure to the space environment. Our previous studies showed that mice exposed to space for 13.5 days had decreased glutathione levels, suggesting impairments in oxidative defense. Here we performed unbiased, unsupervised and integrated multi-‘omic analyses of metabolomic and transcriptomic datasets from mice flown aboard the Space Shuttle Atlantis. Enrichment analyses of metabolite and gene sets showed significant changes in osmolyte concentrations and pathways related to glycerophospholipid and sphingolipid metabolism, likely consequences of relative dehydration of the spaceflight mice. However, we also found increased enrichment of aminoacyl-tRNA biosynthesis and purine metabolic pathways, concomitant with enrichment of genes associated with autophagy and the ubiquitin-proteasome. When taken together with a downregulation in nuclear factor (erythroid-derived 2)-like 2-mediated signaling, our analyses suggest that decreased hepatic oxidative defense may lead to aberrant tRNA post-translational processing, induction of degradation programs and senescence-associated mitochondrial dysfunction in response to the spaceflight environment. PMID:28953266

Spaceflight Activates Autophagy Programs and the Proteasome in Mouse Liver.

PubMed

Blaber, Elizabeth A; Pecaut, Michael J; Jonscher, Karen R

2017-09-27

Increased oxidative stress is an unavoidable consequence of exposure to the space environment. Our previous studies showed that mice exposed to space for 13.5 days had decreased glutathione levels, suggesting impairments in oxidative defense. Here we performed unbiased, unsupervised and integrated multi-'omic analyses of metabolomic and transcriptomic datasets from mice flown aboard the Space Shuttle Atlantis. Enrichment analyses of metabolite and gene sets showed significant changes in osmolyte concentrations and pathways related to glycerophospholipid and sphingolipid metabolism, likely consequences of relative dehydration of the spaceflight mice. However, we also found increased enrichment of aminoacyl-tRNA biosynthesis and purine metabolic pathways, concomitant with enrichment of genes associated with autophagy and the ubiquitin-proteasome. When taken together with a downregulation in nuclear factor (erythroid-derived 2)-like 2-mediated signaling, our analyses suggest that decreased hepatic oxidative defense may lead to aberrant tRNA post-translational processing, induction of degradation programs and senescence-associated mitochondrial dysfunction in response to the spaceflight environment.

Physiological and Functional Alterations after Spaceflight and Bed Rest.

PubMed

Mulavara, Ajitkumar P; Peters, Brian T; Miller, Chris A; Kofman, Igor S; Reschke, Millard F; Taylor, Laura C; Lawrence, Emily L; Wood, Scott J; Laurie, Steven S; Lee, Stuart M C; Buxton, Roxanne E; May-Phillips, Tiffany R; Stenger, Michael B; Ploutz-Snyder, Lori L; Ryder, Jeffrey W; Feiveson, Alan H; Bloomberg, Jacob J

2018-04-03

Exposure to microgravity causes alterations in multiple physiological systems, potentially impacting the ability of astronauts to perform critical mission tasks. The goal of this study was to determine the effects of spaceflight on functional task performance and to identify the key physiological factors contributing to their deficits. A test battery comprised of 7 functional tests and 15 physiological measures was used to investigate the sensorimotor, cardiovascular and neuromuscular adaptations to spaceflight. Astronauts were tested before and after 6-month spaceflights. Subjects were also tested before and after 70 days of 6° head-down bed rest, a spaceflight analog, to examine the role of axial body unloading on the spaceflight results. These subjects included Control and Exercise groups to examine the effects of exercise during bed rest. Spaceflight subjects showed the greatest decrement in performance during functional tasks that required the greatest demand for dynamic control of postural equilibrium which was paralleled by similar decrements in sensorimotor tests that assessed postural and dynamic gait control. Other changes included reduced lower limb muscle performance and increased heart rate to maintain blood pressure. Exercise performed during bed rest prevented detrimental change in neuromuscular and cardiovascular function, however, both bed rest groups experienced functional and balance deficits similar to spaceflight subjects. Bed rest data indicates that body support unloading experienced during spaceflight contributes to postflight postural control dysfunction. Further, the bed rest results in the Exercise group of subjects confirm that resistance and aerobic exercises performed during spaceflight can play an integral role in maintaining neuromuscular and cardiovascular function, which can help in reducing decrements in functional performance. These results indicate that a countermeasure to mitigate postflight postural control dysfunction is required to maintain functional performance.

Immune Dysfunction in Cirrhosis

PubMed Central

Noor, Mohd Talha; Manoria, Piyush

2017-01-01

Abstract Cirrhosis due to any etiology disrupts the homeostatic role of liver in the body. Cirrhosis-associated immune dysfunction leads to alterations in both innate and acquired immunity, due to defects in the local immunity of liver as well as in systemic immunity. Cirrhosis-associated immune dysfunction is a dynamic phenomenon, comprised of both increased systemic inflammation and immunodeficiency, and is responsible for 30% mortality. It also plays an important role in acute as well as chronic decompensation. Immune paralysis can accompany it, which is characterized by increase in anti-inflammatory cytokines and suppression of proinflammatory cytokines. There is also presence of increased gut permeability, reduced gut motility and altered gut flora, all of which leads to increased bacterial translocation. This increased bacterial translocation and consequent endotoxemia leads to increased blood stream bacterial infections that cause systemic inflammatory response syndrome, sepsis, multiorgan failure and death. The gut microbiota of cirrhotic patients has more pathogenic microbes than that of non-cirrhotic individuals, and this disturbs the homeostasis and favors gut translocation. Prompt diagnosis and treatment of such infections are necessary for better survival. We have reviewed the various mechanisms of immune dysfunction and its consequences in cirrhosis. Recognizing the exact pathophysiology of immune dysfunction will help treating clinicians in avoiding its complications in their patients and can lead to newer therapeutic interventions and reducing the morbidity and mortality rates. PMID:28507927

Synthetic Biology and Human Health: Potential Applications for Spaceflight

NASA Technical Reports Server (NTRS)

Karouia, Fathi; Carr, Christopher; Cai, Yizhi; Chen, Y.; Grenon, Marlene; Larios-Sanz, Maia; Jones, Jeffrey A.; Santos, Orlando

2011-01-01

Human space travelers experience a unique environment that affects homeostasis and physiologic adaptation. Spaceflight-related changes have been reported in the musculo-skeletal, cardiovascular, neurovestibular, endocrine, and immune systems. The spacecraft environment further subjects the traveler to noise and gravitational forces, as well as airborne chemical, microbiological contaminants, and radiation exposure. As humans prepare for longer duration missions effective countermeasures must be developed, verified, and implemented to ensure mission success. Over the past ten years, synthetic biology has opened new avenues for research and development in areas such as biological control, biomaterials, sustainable energy production, bioremediation, and biomedical therapies. The latter in particular is of great interest to the implementation of long-duration human spaceflight capabilities. This article discusses the effects of spaceflight on humans, and reviews current capabilities and potential needs associated with the health of the astronauts where synthetic biology could play an important role in the pursuit of space exploration.

Identifying patterns of immune-related disease: use in disease prevention and management.

PubMed

Dietert, Rodney R; Zelikoff, Judith T

2010-05-01

Childhood susceptibility to diseases linked with immune dysfunction affects over a quarter of the pediatric population in some countries. While this alone is a significant health issue, the actual impact of immune-related diseases extends over a lifetime and involves additional secondary conditions. Some comorbidities are well known (e.g., allergic rhinitis and asthma). However, no systematic approach has been used to identify life-long patterns of immune-based disease where the primary condition arises in childhood. Such information is useful for both disease prevention and treatment approaches. Recent primary research papers as well as review articles were obtained from PubMed, Chem Abstracts, Biosis and from the personal files of the authors. Search words used were: the diseases and conditions shown Figs. 1 and 2 in conjunction with comorbid, comorbidities, pediatric, childhood, adult, immune, immune dysfunction, allergy, autoimmune, inflammatory, infectious, health risks, environment, risk factors. Childhood diseases such as asthma, type-1 diabetes, inflammatory bowel disease, respiratory infections /rhinitis, recurrent otitis media, pediatric celiac, juvenile arthritis and Kawasaki disease are examples of significant childhood health problems where immune dysfunction plays a significant role. Each of these pediatric diseases is associated with increased risk of several secondary conditions, many of which appear only later in life. To illustrate, four prototypes of immune-related disease patterns (i.e., allergy, autoimmunity, inflammation and infectious disease) are shown as tools for: 1) enhanced disease prevention; 2) improved management of immune-based pediatric diseases; and 3) better recognition of underlying pediatric immune dysfunction. Identification of immune-related disease patterns beginning in childhood provides the framework for examining the underlying immune dysfunctions that can contribute to additional diseases in later life. Many pediatric diseases associated with dysfunctional immune responses have been linked with an elevated risk of other diseases or conditions as the child ages. Diseases within a pattern may be interlinked based on underlying immune dysfunctions and/or current therapeutic approaches for managing the entryway diseases. It may be beneficial to consider treatment options for the earliest presenting diseases that will concomitantly reduce the risk of immune-linked secondary conditions. Additionally, improved disease prevention is possible with more relevant and age-specific immune safety testing.

Antibody responses to bacteriophage phi X-174 in human subjects exposed to the antarctic winter-over model of spaceflight

NASA Technical Reports Server (NTRS)

Shearer, W. T.; Lugg, D. J.; Rosenblatt, H. M.; Nickolls, P. M.; Sharp, R. M.; Reuben, J. M.; Ochs, H. D.

2001-01-01

BACKGROUND: It has been proposed that exposure to long-term spaceflight conditions (stress, isolation, sleep disruption, containment, microbial contamination, and solar radiation) or to ground-based models of spaceflight will alter human immune responses, but specific antibody responses have not been fully evaluated. OBJECTIVE: We sought to determine whether exposure to the 8-month Antarctic winter-over model of spaceflight would alter human antibody responses. METHODS: During the 1999 Australian National Antarctic Research Expeditions, 11 adult study subjects at Casey, Antarctica, and 7 control subjects at Macquarie Island, sub-Antarctica, received primary and secondary immunizations with the T cell-dependent neoantigen bacteriophage phi X-174. Periodic plasma samples were analyzed for specific antibody function. RESULTS: All of the subjects from Casey, Antarctica, cleared bacteriophage phi X-174 normally by 1 week after primary immunization, and all had normal primary and secondary antibody responses, including immunologic memory amplification and switch from IgM to IgG antibody production. One subject showed a high normal pattern, and one subject had a low normal pattern. The control subjects from Macquarie Island also had normal immune responses to bacteriophage phi X-174. CONCLUSIONS: These data do not support the hypothesis that de novo specific antibody responses of subjects become defective during the conditions of the Antarctic winter-over. Because the Antarctic winter-over model of spaceflight lacks the important factors of microgravity and solar radiation, caution must be used in interpreting these data to anticipate normal antibody responses in long-term spaceflight.

Immunological and Hematopoietic Biotechnology Studies

NASA Technical Reports Server (NTRS)

Fernandez-Botran, Rafael; Sonnenfeld, Gerald

1996-01-01

The purpose of the work carried under this interchanges was to support the development of space flight biotechnology experiments in the areas of immunology and hematopoiesis to facilitate the commercial development of space. The studies involved the interaction and development of experiments with biotechnology companies for necessary ground-based studies to allow the development of flight studies. The thrust of the work was to develop experiments with the Chiron Corporation and Bioserve involving the use of interleukin-2 to modulate the effects of spaceflight on immune responses. Spaceflight has been shown to have multiple effects on immune responses (1). lnterleukin-2 is an immuno-regulator that could have potential to counter some of the alterations induced in immune responses by spaceflight (1). To test this possibility before flight, rats were suspended antiorthostatically (2) and treated with interleukin-2. Antiorthostatic suspension is a model for some of the effects of spaceflight on immune responses (2). The interleukin-2 was given to see if it could alter some of the effects of suspension. This was achieved. As a result of these studies, two flight experiments were developed and flown with the Chiron Corp. And Bioserve to determine if use of interleukin-2 could prevent or attenuate the effects of space flight on immune responses.

Immune system changes during simulated planetary exploration on Devon Island, high arctic

PubMed Central

Crucian, Brian; Lee, Pascal; Stowe, Raymond; Jones, Jeff; Effenhauser, Rainer; Widen, Raymond; Sams, Clarence

2007-01-01

Background Dysregulation of the immune system has been shown to occur during spaceflight, although the detailed nature of the phenomenon and the clinical risks for exploration class missions have yet to be established. Also, the growing clinical significance of immune system evaluation combined with epidemic infectious disease rates in third world countries provides a strong rationale for the development of field-compatible clinical immunology techniques and equipment. In July 2002 NASA performed a comprehensive immune assessment on field team members participating in the Haughton-Mars Project (HMP) on Devon Island in the high Canadian Arctic. The purpose of the study was to evaluate the effect of mission-associated stressors on the human immune system. To perform the study, the development of techniques for processing immune samples in remote field locations was required. Ten HMP-2002 participants volunteered for the study. A field protocol was developed at NASA-JSC for performing sample collection, blood staining/processing for immunophenotype analysis, whole-blood mitogenic culture for functional assessments and cell-sample preservation on-location at Devon Island. Specific assays included peripheral leukocyte distribution; constitutively activated T cells, intracellular cytokine profiles, plasma cortisol and EBV viral antibody levels. Study timepoints were 30 days prior to mission start, mid-mission and 60 days after mission completion. Results The protocol developed for immune sample processing in remote field locations functioned properly. Samples were processed on Devon Island, and stabilized for subsequent analysis at the Johnson Space Center in Houston. The data indicated that some phenotype, immune function and stress hormone changes occurred in the HMP field participants that were largely distinct from pre-mission baseline and post-mission recovery data. These immune changes appear similar to those observed in astronauts following spaceflight. Conclusion The immune system changes described during the HMP field deployment validate the use of the HMP as a ground-based spaceflight/planetary exploration analog for some aspects of human physiology. The sample processing protocol developed for this study may have applications for immune studies in remote terrestrial field locations. Elements of this protocol could possibly be adapted for future in-flight immunology studies conducted during space missions. PMID:17521440

Global transcriptomic analysis suggests carbon dioxide as an environmental stressor in spaceflight: A systems biology GeneLab case study.

PubMed

Beheshti, Afshin; Cekanaviciute, Egle; Smith, David J; Costes, Sylvain V

2018-03-08

Spaceflight introduces a combination of environmental stressors, including microgravity, ionizing radiation, changes in diet and altered atmospheric gas composition. In order to understand the impact of each environmental component on astronauts it is important to investigate potential influences in isolation. Rodent spaceflight experiments involve both standard vivarium cages and animal enclosure modules (AEMs), which are cages used to house rodents in spaceflight. Ground control AEMs are engineered to match the spaceflight environment. There are limited studies examining the biological response invariably due to the configuration of AEM and vivarium housing. To investigate the innate global transcriptomic patterns of rodents housed in spaceflight-matched AEM compared to standard vivarium cages we utilized publicly available data from the NASA GeneLab repository. Using a systems biology approach, we observed that AEM housing was associated with significant transcriptomic differences, including reduced metabolism, altered immune responses, and activation of possible tumorigenic pathways. Although we did not perform any functional studies, our findings revealed a mild hypoxic phenotype in AEM, possibly due to atmospheric carbon dioxide that was increased to match conditions in spaceflight. Our investigation illustrates the process of generating new hypotheses and informing future experimental research by repurposing multiple space-flown datasets.

Risk of Crew Adverse Health Event Due to Altered Immune Response

NASA Technical Reports Server (NTRS)

Crucian, Brian; Kunz, Hawley; Sams, Clarence F.

2015-01-01

Determining the effect of space travel on the human immune system has proven to be extremely challenging. Limited opportunities for in-flight studies, varying mission durations, technical and logistical obstacles, small subject numbers, and a broad range of potential assays have contributed to this problem. Additionally, the inherent complexity of the immune system, with its vast array of cell populations, sub-populations, diverse regulatory molecules, and broad interactions with other physiological systems, makes determining precise variables to measure very difficult. There is also the challenge of determining the clinical significance of any observed immune alterations. Will such a change lead to disease, or is it a transient subclinical observation related to short-term stress? The effect of this problem may be observed by scanning publications associated with immunity and spaceflight, which began to appear during the 1970s. Although individually they are each valid studies, the comprehensive literature to date suffers from widely varying sampling methods and assay techniques, low subject counts, and sometimes a disparate focus on narrow aspects of immunity. The most clinically relevant data are derived from in-flight human studies, which have demonstrated altered cell-mediated immunity and reactivation of latent herpes viruses. Much more data are available from post-flight testing of humans, with clear evidence of altered cytokine production patterns, altered leukocyte distribution, continued latent viral reactivation, and evidence of dramatically altered virus-specific immunity. It is unknown if post-flight assessments relate to the in-flight condition or are a response to landing stress and readaptation. In-flight culture of cells has clearly demonstrated that immune cells are gravity-sensitive and display altered functional characteristics. It is unknown if these data are related to in vivo immune cell function or are an artifact of microgravity culture. Ground analog testing of humans and animals, as well as microgravity-analog cell culture, has demonstrated utility. However, in all cases, it is not known with certainty if these data would reflect similar testing during space travel. Given their ready availability, ground analogs may be extremely useful for assay development and the evaluation of potential countermeasures. In general, the evidence base suffers from widely disparate studies on small numbers of subjects that do not directly correlate well with each other or spaceflight itself. Also lacking are investigations of the effect of gender on adaption to spaceflight. This results in significant knowledge 'gaps' that must be filled by future studies to completely determine any clinical risk related to immunity for human exploration-class space missions. These gaps include a significant lack of in-flight data, particularly during long-duration space missions. The International Space Station represents an excellent science platform with which to address this knowledge gap. Other knowledge gaps include lack of a single validated ground analog for the phenomenon and a lack of flight-compatible laboratory equipment capable of monitoring astronauts (for either clinical or research purposes). However, enough significant data exist, as described in this manuscript, to warrant addressing this phenomenon during the utilization phase of the ISS. A recent Space Shuttle investigation has confirmed the 31 in-flight nature of immune dysregulation, demonstrating that it is not merely a post-flight phenomenon. Several current studies are ongoing onboard the ISS that should thoroughly characterize the phenomenon. NASA recognizes that if spaceflight-associated immune dysregulation persists during exploration flights in conjunction with other dangers, such as high-energy radiation, the result may be a significant clinical risk. This emphasizes the need for a continued integrated comprehensive approach to determining the effect of prolonged spaceflight, separated from transient launch and landing stresses, on human immunity. After such studies, the phenomenon will be understood, and, hopefully, a monitoring strategy will have been developed that could be used to monitor the effectiveness of countermeasure

Epigenetic alterations are associated with monocyte immune dysfunctions in HIV-1 infection.

PubMed

Espíndola, Milena S; Soares, Luana S; Galvão-Lima, Leonardo J; Zambuzi, Fabiana A; Cacemiro, Maira C; Brauer, Verônica S; Marzocchi-Machado, Cleni M; de Souza Gomes, Matheus; Amaral, Laurence R; Martins-Filho, Olindo A; Bollela, Valdes R; Frantz, Fabiani G

2018-04-03

Monocytes are key cells in the immune dysregulation observed during human immunodeficiency virus (HIV) infection. The events that take place specifically in monocytes may contribute to the systemic immune dysfunction characterized by excessive immune activation in infected individuals, which directly correlates with pathogenesis and progression of the disease. Here, we investigated the immune dysfunction in monocytes from untreated and treated HIV + patients and associated these findings with epigenetic changes. Monocytes from HIV patients showed dysfunctional ability of phagocytosis and killing, and exhibited dysregulated cytokines and reactive oxygen species production after M. tuberculosis challenge in vitro. In addition, we showed that the expression of enzymes responsible for epigenetic changes was altered during HIV infection and was more prominent in patients that had high levels of soluble CD163 (sCD163), a newly identified plasmatic HIV progression biomarker. Among the enzymes, histone acetyltransferase 1 (HAT1) was the best epigenetic biomarker correlated with HIV - sCD163 high patients. In conclusion, we confirmed that HIV impairs effector functions of monocytes and these alterations are associated with epigenetic changes that once identified could be used as targets in therapies aiming the reduction of the systemic activation state found in HIV patients.

Divergent Annexin A1 expression in periphery and gut is associated with systemic immune activation and impaired gut immune response during SIV infection

PubMed Central

Sena, Angela A. S.; Glavan, Tiffany; Jiang, Guochun; Sankaran-Walters, Sumathi; Grishina, Irina; Dandekar, Satya; Goulart, Luiz R.

2016-01-01

HIV-1 disease progression is paradoxically characterized by systemic chronic immune activation and gut mucosal immune dysfunction, which is not fully defined. Annexin A1 (ANXA1), an inflammation modulator, is a potential link between systemic inflammation and gut immune dysfunction during the simian immunodeficiency virus (SIV) infection. Gene expression of ANXA1 and cytokines were assessed in therapy-naïve rhesus macaques during early and chronic stages of SIV infection and compared with SIV-negative controls. ANXA1 expression was suppressed in the gut but systemically increased during early infection. Conversely, ANXA1 expression increased in both compartments during chronic infection. ANXA1 expression in peripheral blood was positively correlated with HLA-DR+CD4+ and CD8+ T-cell frequencies, and negatively associated with the expression of pro-inflammatory cytokines and CCR5. In contrast, the gut mucosa presented an anergic cytokine profile in relation to ANXA1 expression. In vitro stimulations with ANXA1 peptide resulted in decreased inflammatory response in PBMC but increased activation of gut lymphocytes. Our findings suggest that ANXA1 signaling is dysfunctional in SIV infection, and may contribute to chronic inflammation in periphery and with immune dysfunction in the gut mucosa. Thus, ANXA1 signaling may be a novel therapeutic target for the resolution of immune dysfunction in HIV infection. PMID:27484833

Voluntary immunomodulation: potentiality and implications for long-duration manned space-flights

NASA Astrophysics Data System (ADS)

Geuna, Stefano

The influence of psychological and neural factors on immunologic activity has been dedicated a growing interest over the past fifteen years, since the publication ofPsychoneuroimmunology by Robert Ader in 1981. Studies on this topic gave evidence for bi-directional communication between psychosocial, behavioural, neuroanatomical and neuroendocrine processes with the immune system and the detrimental effects of various stressors, physical and psychological, on immune reactions were widely investigated with reports of stress-induced changes in immune paramenters and immunocompetence. Much of the evidence support the notion that stress is associated with an increase in those diseases against which the immune system defends. Recently, several studies showed that immune functions can be influenced voluntarily and the term voluntary immunomodulation was coined to describe the use of various hypnosis-like and relaxation/imagery techniques for the self-regulation of immune activity. Alterations in the immune regulatory system are one of the most critical issues to be addressed in relation to crew health management during space missions, especially long-term ones. Providing crewmembers with a tool to enhance immunocompetence might be of great value to defend against some severe diseases, such as cancer and infectious illness, which may be elicited in outer space. In this view, a critical assessment of the potential usefulness of voluntary immunomodulation for crew health maintenance during manned space-flight is presented and discussed.

NASA 14 Day Undersea Missions: A Short-Duration Spaceflight Analog for Immune System Dysregulation?

NASA Technical Reports Server (NTRS)

Crucian, B. E.; Stowe, R. P.; Mehta, S. K.; Chouker, A.; Feuerecker, M.; Quiriarte, H.; Pierson, D. L.; Sams, C. F.

2011-01-01

This poster paper reviews the use of 14 day undersea missions as a possible analog for short duration spaceflight for the study of immune system dysregulation. Sixteen subjects from the the NASA Extreme Enviro nment Mission Operations (NEEMO) 12, 13 and 14 missions were studied for immune system dysregulation. The assays that are presented in this poster are the Virleukocyte subsets, the T Cell functions, and the intracellular/secreted cytokine profiles. Other assays were performed, but are not included in this presntation.

Towards human exploration of space: The THESEUS review series on immunology research priorities

PubMed Central

Frippiat, Jean-Pol; Crucian, Brian E; de Quervain, Dominique J-F; Grimm, Daniela; Montano, Nicola; Praun, Siegfried; Roozendaal, Benno; Schelling, Gustav; Thiel, Manfred; Ullrich, Oliver; Choukèr, Alexander

2016-01-01

Dysregulation of the immune system occurs during spaceflight and may represent a crew health risk during exploration missions because astronauts are challenged by many stressors. Therefore, it is crucial to understand the biology of immune modulation under spaceflight conditions in order to be able to maintain immune homeostasis under such challenges. In the framework of the THESEUS project whose aim was to develop an integrated life sciences research roadmap regarding human space exploration, experts working in the field of space immunology, and related disciplines, established a questionnaire sent to scientists around the world. From the review of collected answers, they deduced a list of key issues and provided several recommendations such as a maximal exploitation of currently available resources on Earth and in space, and to increase increments duration for some ISS crew members to 12 months or longer. These recommendations should contribute to improve our knowledge about spaceflight effects on the immune system and the development of countermeasures that, beyond astronauts, could have a societal impact. PMID:28725745

Towards human exploration of space: The THESEUS review series on immunology research priorities.

PubMed

Frippiat, Jean-Pol; Crucian, Brian E; de Quervain, Dominique J-F; Grimm, Daniela; Montano, Nicola; Praun, Siegfried; Roozendaal, Benno; Schelling, Gustav; Thiel, Manfred; Ullrich, Oliver; Choukèr, Alexander

2016-01-01

Dysregulation of the immune system occurs during spaceflight and may represent a crew health risk during exploration missions because astronauts are challenged by many stressors. Therefore, it is crucial to understand the biology of immune modulation under spaceflight conditions in order to be able to maintain immune homeostasis under such challenges. In the framework of the THESEUS project whose aim was to develop an integrated life sciences research roadmap regarding human space exploration, experts working in the field of space immunology, and related disciplines, established a questionnaire sent to scientists around the world. From the review of collected answers, they deduced a list of key issues and provided several recommendations such as a maximal exploitation of currently available resources on Earth and in space, and to increase increments duration for some ISS crew members to 12 months or longer. These recommendations should contribute to improve our knowledge about spaceflight effects on the immune system and the development of countermeasures that, beyond astronauts, could have a societal impact.

The role of immune dysfunction in the pathophysiology of autism

PubMed Central

Onore, Charity; Careaga, Milo; Ashwood, Paul

2012-01-01

Autism spectrum disorders (ASD) are a complex group of neurodevelopmental disorders encompassing impairments in communication, social interactions and restricted stereotypical behaviors. Although a link between altered immune responses and ASD was first recognized nearly 40 years ago, only recently has new evidence started to shed light on the complex multifaceted relationship between immune dysfunction and behavior in ASD. Neurobiological research in ASD has highlighted pathways involved in neural development, synapse plasticity, structural brain abnormalities, cognition and behavior. At the same time, several lines of evidence point to altered immune dysfunction in ASD that directly impacts some or all these neurological processes. Extensive alterations in immune function have now been described in both children and adults with ASD, including ongoing inflammation in brain specimens, elevated pro-inflammatory cytokine profiles in the CSF and blood, increased presence of brain-specific auto-antibodies and altered immune cell function. Furthermore, these dysfunctional immune responses are associated with increased impairments in behaviors characteristic of core features of ASD, in particular, deficits in social interactions and communication. This accumulating evidence suggests that immune processes play a key role in the pathophysiology of ASD. This review will discuss the current state of our knowledge of immune dysfunction in ASD, how these findings may impact on underlying neuro-immune mechanisms and implicate potential areas where the manipulation of the immune response could have an impact on behavior and immunity in ASD. PMID:21906670

Microgravity as a novel environmental signal affecting Salmonella enterica serovar Typhimurium virulence

NASA Technical Reports Server (NTRS)

Nickerson, C. A.; Ott, C. M.; Mister, S. J.; Morrow, B. J.; Burns-Keliher, L.; Pierson, D. L.

2000-01-01

The effects of spaceflight on the infectious disease process have only been studied at the level of the host immune response and indicate a blunting of the immune mechanism in humans and animals. Accordingly, it is necessary to assess potential changes in microbial virulence associated with spaceflight which may impact the probability of in-flight infectious disease. In this study, we investigated the effect of altered gravitational vectors on Salmonella virulence in mice. Salmonella enterica serovar Typhimurium grown under modeled microgravity (MMG) were more virulent and were recovered in higher numbers from the murine spleen and liver following oral infection compared to organisms grown under normal gravity. Furthermore, MMG-grown salmonellae were more resistant to acid stress and macrophage killing and exhibited significant differences in protein synthesis than did normal-gravity-grown cells. Our results indicate that the environment created by simulated microgravity represents a novel environmental regulatory factor of Salmonella virulence.

Hyperbaric hyperoxia alters innate immune functional properties during NASA Extreme Environment Mission Operation (NEEMO).

PubMed

Strewe, C; Crucian, B E; Sams, C F; Feuerecker, B; Stowe, R P; Choukèr, A; Feuerecker, M

2015-11-01

Spaceflight is associated with immune dysregulation which is considered as risk factor for the performance of exploration-class missions. Among the consequences of confinement and other environmental factors of living in hostile environments, the role of different oxygen concentrations is of importance as either low (e.g. as considered for lunar or Martian habitats) or high (e.g. during extravehicular activities) can trigger immune dysfunction. The aim of this study was to investigate the impact of increased oxygen availability--generated through hyperbaricity--on innate immune functions in the course of a 14 days NEEMO mission. 6 male subjects were included into a 14 days undersea deployment at the Aquarius station (Key Largo, FL, USA). The underwater habitat is located at an operating depth of 47 ft. The 2.5 times higher atmospheric pressure in the habitat leads to hyperoxia. The collection of biological samples occurred 6 days before (L-6), at day 7 (MD7) and 11/13 (MD11/13) during the mission, and 90 days thereafter (R). Blood analyses included differential blood cell count, ex vivo innate immune activation status and inhibitory competences of granulocytes. The absolute leukocyte count showed an increase during deployment as well as the granulocyte and monocyte count. Lymphocyte count was decreased on MD7. The assessments of native adhesion molecules on granulocytes (CD11b, CD62L) indicated a highly significant cellular activation (L-6 vs. MD7/MD13) during mission. In contrast, granulocytes were more sensitive towards anti-inflammatory stimuli (adenosine) on MD13. Living in the NEEMO habitat for 14 days induced significant immune alterations as seen by an activation of adhesion molecules and vice versa higher sensitivity towards inhibition. This investigation under hyperbaric hyperoxia is important especially for Astronauts' immune competence during extravehicular activities when exposed to similar conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

Plasma Cytokine Levels During Long-Duration Spaceflight

NASA Technical Reports Server (NTRS)

Crucian, Brian E.; Zwart, Sara R.; Quiriarte, Heather A.; Smith, Scott M.; Sams, Clarence F.

2011-01-01

Reduced T cell, granulocyte, NK and monocyte function have all been reported following both long and short duration spaceflight, however these data indicate crews are generally not experiencing inflammatory or adaptive immune activation during spaceflight. There appear to be varied individual crew responses, and specific relationships between cytokines and markers of iron status and muscle turnover that warrant further evaluation. Increases in growth factors and chemokines may indicate other types of adaptation occurring during spaceflight, such as attempts to overcome diminished immunocyte function.

Cellular immunity and lymphokine production during spaceflights

NASA Technical Reports Server (NTRS)

Konstantinova, I. V.; Sonnenfeld, G.; Lesniak, A. T.; Shaffar, L.; Mandel, A.; Rykova, M. P.; Antropova, E. N.; Ferrua, B.

1991-01-01

Results are presented on changes in cellular immunity and in the production of lymphokine in spacecrews during spaceflights. Measurements were carried out on blood samples collected from 50 cosmonauts before and after spaceflights of different duration, on board Salyut-6, Salyut-7, or Mir. Additional data were obtained from rats flown on board the Cosmos-1667 and Cosmos-1887 biosatellites. The parameters measured included the PHA responsiveness of T lymphocytes, the activity of T-helper cells and of nonspecific T suppressors, the activity of the so-called natural killer lymphocytes, the production of gamma-interferon, and the cell-surface markers. Results showed that the frequency and the extent of changes in the immunologic resistance of subjects depended on the duration of the flight. However, even after the most prolonged (365 days) spaceflight, the changes observed were mostly of a functional character with subsequent rapid return to normal.

Development of an Integrated Sensorimotor Countermeasure Suite for Spaceflight Operations

NASA Technical Reports Server (NTRS)

Bloomberg, J. J.; Batson, C. D.; Caldwell, E. E. (Inventor); Feiveson, A. H.; Kreutzberg, G. A.; Miller, C. A.; Mulavara, A. P.; Oddsson, L. I. E.; Peters, B. T.; Ploutz-Synder, L. L.;

Dysbiosis and Immune Dysregulation in Outer Space.

PubMed

Cervantes, Jorge L; Hong, Bo-Young

2016-01-01

In space, the lifestyle, relative sterility of spaceship and extreme environmental stresses, such as microgravity and cosmic radiation, can compromise the balance between human body and human microbiome. An astronaut's body during spaceflight encounters increased risk for microbial infections and conditions because of immune dysregulation and altered microbiome, i.e. dysbiosis. This risk is further heightened by increase in virulence of pathogens in microgravity. Health status of astronauts might potentially benefit from maintaining a healthy microbiome by specifically managing their diet on space in addition to probiotic therapies. This review focuses on the current knowledge/understanding of how spaceflight affects human immunity and microbiome.

Impaired interferon signaling is a common immune defect in human cancer

PubMed Central

Critchley-Thorne, Rebecca J.; Simons, Diana L.; Yan, Ning; Miyahira, Andrea K.; Dirbas, Frederick M.; Johnson, Denise L.; Swetter, Susan M.; Carlson, Robert W.; Fisher, George A.; Koong, Albert; Holmes, Susan; Lee, Peter P.

2009-01-01

Immune dysfunction develops in patients with many cancer types and may contribute to tumor progression and failure of immunotherapy. Mechanisms underlying cancer-associated immune dysfunction are not fully understood. Efficient IFN signaling is critical to lymphocyte function; animals rendered deficient in IFN signaling develop cancer at higher rates. We hypothesized that altered IFN signaling may be a key mechanism of immune dysfunction common to cancer. To address this, we assessed the functional responses to IFN in peripheral blood lymphocytes from patients with 3 major cancers: breast cancer, melanoma, and gastrointestinal cancer. Type-I IFN (IFN-α)-induced signaling was reduced in T cells and B cells from all 3 cancer-patient groups compared to healthy controls. Type-II IFN (IFN-γ)-induced signaling was reduced in B cells from all 3 cancer patient groups, but not in T cells or natural killer cells. Impaired-IFN signaling was equally evident in stage II, III, and IV breast cancer patients, and downstream functional defects in T cell activation were identified. Taken together, these findings indicate that defects in lymphocyte IFN signaling arise in patients with breast cancer, melanoma, and gastrointestinal cancer, and these defects may represent a common cancer-associated mechanism of immune dysfunction. PMID:19451644

The Immune System’s Role in Sepsis Progression, Resolution and Long-Term Outcome

PubMed Central

Delano, Matthew J.; Ward, Peter A.

2016-01-01

SUMMARY Sepsis occurs when an infection exceeds local tissue containment and induces a series of dysregulated physiologic responses that result in organ dysfunction. A subset of patients with sepsis progress to septic shock, defined by profound circulatory, cellular, and metabolic abnormalities, and associated with a greater mortality. Historically, sepsis-induced organ dysfunction and lethality were attributed to the complex interplay between the initial inflammatory and later anti-inflammatory responses. With advances in intensive care medicine and goal-directed interventions, early 30-day sepsis mortality has diminished, only to steadily escalate long after “recovery” from acute events. Since so many sepsis survivors succumb later to persistent, recurrent, nosocomial and secondary infections, many investigators have turned their attention to the long-term sepsis-induced alterations in cellular immune function. Sepsis clearly alters the innate and adaptive immune responses for sustained periods of time after clinical recovery, with immune suppression, chronic inflammation, and persistence of bacterial representing such alterations. Understanding that sepsis-associated immune cell defects correlate with long-term mortality, more investigations have centered on the potential for immune modulatory therapy to improve long term patient outcomes. These efforts are focused on more clearly defining and effectively reversing the persistent immune cell dysfunction associated with long-term sepsis mortality. PMID:27782333

Effect of spaceflight on natural killer cell activity

NASA Technical Reports Server (NTRS)

Rykova, Marina P.; Sonnenfeld, Gerald; Lesniak, A. T.; Taylor, Gerald R.; Meshkov, Dimitrii O.; Mandel, Adrian D.; Medvedev, Andrei E.; Berry, Wallace D.; Fuchs, Boris B.; Konstantinova, Irina V.

1992-01-01

The effects of spaceflight on immune cell function were determined in rats flown on Cosmos 2044. Control groups included vivarium, synchronous, and antiorthostatically suspended rats. The ability of natural killer cells to lyse two different target cell lines was determined. Spleen and bone marrow cells obtained from flight rats showed significantly inhibited cytotoxicity for YAC-1 target cells compared with cells from synchronous control rats. This could have been due to exposure of the rats to microgravity. Antiorthostatic suspension did not affect the level of cytotoxicity from spleen cells of suspended rats for YAC-1 cells. On the other hand, cells from rats flown in space showed no significant differences from vivarium and synchronous control rats in cytotoxicity for K-562 target cells. Binding of natural killer cells to K-562 target cells was unaffected by spaceflight. Antiorthostatic suspension resulted in higher levels of cytotoxicity from spleen cells for Cr-51-labeled K-562 cells. The results indicate differential effects of spaceflight on function of natural killer cells. This shows that spaceflight has selective effects on the immune response.

Comparison of the Physiology of the Spaceflight and Hindlimb Suspended Rat

NASA Technical Reports Server (NTRS)

Grindeland, R. E.; Booth, F. W.

1994-01-01

The suspended rat has been used extensively as a simulation of the spaceflight animal. In suspension, hindlimbs are unloaded from the acceleration of gravity, much as they are in spaceflight. Comparisons of data from spaceflight (microgravity) and suspended (1G) rats have suggested that suspension my be an appropriate model, but no direct comparisons had been made between the spaceflight and suspended rat. Cosmos 2044 afforded the first opportunity to directly compare the effects of hindlimb suspension (HS) and spaceflight (SF) on a broad range of physiological and histological parameters. This paper reports on the comparison of skelton, skeletal muscle, heart, neural, pulmonary, kidney, liver, intestine, blood plasma, immune function, red blood cells, and endocrine and reproductive functions and systems.

Decoupling activation and exhaustion of B cells in spontaneous controllers of HIV infection

PubMed Central

Sciaranghella, Gaia; Tong, Neath; Mahan, Alison E.; Suscovich, Todd J.; Alter, Galit

2013-01-01

Objective To define the impact of chronic viremia and associated immune activation on B-cell exhaustion in HIV infection. Design Progressive HIV infection is marked by B-cell anergy and exhaustion coupled with dramatic hypergammaglobulinemia. Although both upregulation of CD95 and loss of CD21 have been used as markers of infection-associated B-cell dysfunction, little is known regarding the specific profiles of dysfunctional B cells and whether persistent viral replication and its associated immune activation play a central role in driving B-cell dysfunction. Methods Multiparameter flow cytometry was used to define the profile of dysfunctional B cells. The changes in the expression of CD21 and CD95 were tracked on B-cell subpopulations in patients with differential control of viral replication. Results Although the emergence of exhausted, CD21low tissue-like memory B cells followed similar patterns in both progressors and controllers, the frequency of CD21low activated memory B cells was lower in spontaneous controllers. Conclusion Our results suggest that the loss of CD21 and the upregulation of CD95 occur as separate events during the development of B-cell dysfunction. The loss of CD21 is a marker of B-cell exhaustion induced in the absence of appreciable viral replication, whereas the upregulation of CD95 is tightly linked to persistent viral replication and its associated immune activation. Thus, these dysfunctional profiles potentially represent two functionally distinct states within the B-cell compartment. PMID:23135171

Delivery of Probiotics in the Space Food System

NASA Technical Reports Server (NTRS)

Castro, S. L.; Ott, C. M.; Douglas, G. L.

2014-01-01

The addition of probiotic bacteria to the space food system is expected to confer immunostimulatory benefits on crewmembers during spaceflight, counteracting the immune dysregulation that has been documented in spaceflight. Specifically, the probiotic Lactobacillus acidophilus has been shown to promote health benefits including antagonism towards and inhibition of virulence related gene expression in pathogens, mucosal stimulation of immune cells, and a reduction in the occurrence and duration of cold and flu-like symptoms. The optimum delivery system for probiotics has not been determined for spaceflight, where the food system is shelf stable and the lack of refrigeration prevents the use of traditional dairy delivery methods. This work proposes to determine whether L. acidophilus is more viable, and therefore more likely to confer immune benefit, when delivered in a capsule form or when delivered in nonfat dry milk powder with a resuscitation opportunity upon rehydration, following 0, 4, and 8 months of storage at -80degC, 4degC, and 22degC, and both prior to and after challenge with simulated gastric and intestinal juices. We hypothesize that the low moisture neutral dairy matrix provided by the nonfat dry milk, and the rehydration step prior to consumption, will extend probiotic viability and stress tolerance compared to a capsule during potential storage conditions in spaceflight and in simulated digestion conditions.

Delivery of Probiotics in the Space Food System

NASA Technical Reports Server (NTRS)

Castro, S. L.; Ott, C. M.; Douglas, G. L.

2014-01-01

The addition of probiotic bacteria to the space food system is expected to confer immunostimulatory benefits on crewmembers during spaceflight, counteracting the immune dysregulation that has been documented in spaceflight [1]. Specifically, the probiotic Lactobacillus acidophilus has been shown to promote health benefits including antagonism towards and inhibition of virulence related gene expression in pathogens, mucosal stimulation of immune cells, and a reduction in the occurrence and duration of cold and flu-like symptoms [2-5]. The optimum delivery system for probiotics has not been determined for spaceflight, where the food system is shelf stable and the lack of refrigeration prevents the use of traditional dairy delivery methods. This work proposes to determine whether L. acidophilus is more viable, and therefore more likely to confer immune benefit, when delivered in a capsule form or when delivered in nonfat dry milk powder with a resuscitation opportunity upon rehydration, following 0, 4, and 8 months of storage at -80degC, 4degC, and 22degC, and both prior to and after challenge with simulated gastric and intestinal juices. We hypothesize that the low moisture neutral dairy matrix provided by the nonfat dry milk, and the rehydration step prior to consumption, will extend probiotic viability and stress tolerance compared to a capsule during potential storage conditions in spaceflight and in simulated digestion conditions.

Studying the Impact of Spaceflight Environment on Immune Functions Using New Molecular Diagnostics System

NASA Astrophysics Data System (ADS)

Cohen, Luchino

Immune functions are altered during space flights. Latent virus reactivation, reduction in the number of immune cells, decreased cell activation and increased sensitivity of astronauts to infections following their return on Earth demonstrate that the immune system is less efficient during space flight. The causes of this immune deficiency are not fully understood and this dysfunction during long-term missions could result in the appearance of opportunistic infections or a decrease in the immuno-surveillance mechanisms that eradicate cancer cells. Therefore, the immune functions of astronauts will have to be monitored continuously during long-term missions in space, using miniature and semi-automated diagnostic systems. The objectives of this project are to study the causes of space-related immunodeficiency, to develop countermeasures to maintain an optimal immune function and to improve our capacity to detect infectious diseases during space missions through the monitoring of astronauts' immune system. In order to achieve these objectives, an Immune Function Diagnostic System (IFDS) will be designed to perform a set of immunological assays on board spacecrafts or on planet-bound bases. Through flow cytometric assays and molecular biology analyses, this diagnostic system could improve medical surveillance of astronauts and could be used to test countermeasures aimed at preventing immune deficiency during space missions. The capacity of the instrument to assess cellular fluorescence and to quantify the presence of soluble molecules in biological samples would support advanced molecular studies in space life sciences. Finally, such diagnostic system could also be used on Earth in remote areas or in mobile hospitals following natural disasters to fight against infectious diseases and other pathologies.

Probiotics in the Space Food System: Delivery, Microgravity Effects, and the Potential Benefit to Crew Health

NASA Technical Reports Server (NTRS)

Castro, S. L.; Ott, C. M.; Douglas, G. L.

2014-01-01

As mission distance and duration increase, the need grows for non-invasive disease prevention and immunomodulation, especially given the limited medical response capability expected for these missions and the immune dysregulation documented in crew. Additionally, changes in diet, lifestyle, antibiotic usage, and the environmental stresses during spaceflight may alter crewmembers' intestinal microbiome. The addition of probiotic bacteria to the space food system is expected to confer immunostimulatory benefits on crewmembers, with the potential to counteract the immune dysregulation that has been documented in spaceflight. Based on previous studies that demonstrated unique microbiological responses to the low shear environment of spaceflight, probiotic organisms hold the potential to induce enhanced beneficial responses through mechanisms, such as beneficial interactions with human immune cells and repression of colonization of pathogens on the mucosa. The work presented here will begin to address two research gaps related to providing probiotics in spaceflight: 1) delivery, and 2) the effect of the low shear microgravity environment on probiotic attributes. The probiotic Lactobacillus acidophilus was selected for investigation due to its wide commercial use and documented benefits that include inhibition of virulence related gene expression in pathogens and mucosal stimulation of immune cells. The delivery system for probiotics has not been determined for spaceflight, where the food system is shelf stable and the lack of refrigeration prevents the use of traditional dairy delivery methods. In order to demonstrate the potential of the space food system to deliver viable probiotic bacteria to crewmembers, the probiotic L. acidophilus was packaged in high barrier flight packaging in nonfat dry milk (NFDM) or retained in commercial capsule form. Viable cells were enumerated over 8 months of storage at 22, 4, and -80ºC. The survival of L. acidophilus rehydrated in NFDM, in a PBS control, and directly from the capsule was also evaluated following stress challenge with simulated gastric and intestinal juices to determine the method that would deliver the most viable cells to the intestine, where they would be expected to confer beneficial effects. L. acidophilus was found to be stable to gastric and intestinal juice challenge when delivered in rehydrated NFDM, even after two hours of exposure. In comparison, L. acidophilus was reduced by 1-5 logs when exposed to gastric and intestinal juice directly and when rehydrated in a PBS control. Shelf life data indicated that L. acidophilus would require refrigerated or frozen storage to remain viable at adequate levels over the multi-year storage periods required for spaceflight. This study suggests that the protective effect provided by the dairy matrix, and not merely rehydration prior to consumption, extends probiotic viability and stress tolerance during storage in spaceflight and in simulated digestion conditions more adequately than a capsule. In addition to effective delivery, it is essential to understand the microgravity effects on the stress tolerances and genetic expression of probiotic bacteria to enable optimization of growth, survival, strain selection, and conferred benefits in spaceflight. In our current study, ground-based characterization of the growth, stress response, and transcriptomic response of L. acidophilus will be accomplished using the low shear modeled microgravity (LSMMG) culture environment in the rotating wall vessel (RWV). We hypothesize that L. acidophilus will maintain or improve its growth and stress response following culture in the LSMMG environment, and that transcriptomic analysis will define the associated molecular mechanism(s), resulting in the ability to optimize strain selection.

Immune dysfunction prior to Staphylococcus aureus bacteremia is a determinant of long-term mortality.

PubMed

Greenberg, Jared A; David, Michael Z; Hall, Jesse B; Kress, John P

2014-01-01

The clinical implications for patients who survive serious infections are not well understood. It has been hypothesized that the excess mortality for survivors of sepsis observed in epidemiological studies is due to increased vulnerability to subsequent infections. We undertook this study to identify characteristics of patients who are at high risk for death after surviving a common type of blood-stream infection. At a single academic medical center, 237 patients with Staphylococcus aureus bacteremia admitted during a three-year period were retrospectively identified. The primary outcomes were 30-day and 31 to 90-day mortality after the first positive blood culture. The primary predictor variable of interest was clinical immune dysfunction prior to bacteremia. The 30-day mortality was not significantly different for patients with and without prior immune dysfunction. However, during days 31 to 90, 11 patients (20%) with prior immune dysfunction compared to 10 patients (8.6%) without prior immune dysfunction died (OR 2.59, 95% CI 1.03-6.53, p = 0.04). In a Cox-proportional hazard model controlling for age, there was a significant association between prior immune dysfunction and greater 31 to 90 day mortality (HR 2.44, 95% CI 1.01-5.90, p = 0.05) and a non-significant trend towards occurrence of subsequent infections and greater 31 to 90 day mortality (HR 2.12, 95% CI 0.89-5.07, p = 0.09). Patients with prior immune dysfunction are at high risk for death 31 to 90 days, but not <30 days, after S. aureus bacteremia. Further investigation is needed to determine if this finding is due to poor prognosis of chronic disease or increased vulnerability to subsequent infections.

Antiorthostatic suspension as a model for the effects of spaceflight on the immune system

NASA Technical Reports Server (NTRS)

Chapes, S. K.; Mastro, A. M.; Sonnenfeld, G.; Berry, W. D.

1993-01-01

We describe the use and appropriateness of antiorthostatic suspension in immunological investigations. This manuscript describes the model and discusses how well data obtained by using the model correlate with spaceflight data. This review concludes with some suggestions for future experiments using antiorthostatic suspension.

Neuro-immune dysfunction during brain aging: new insights in microglial cell regulation.

PubMed

Matt, Stephanie M; Johnson, Rodney W

2016-02-01

Microglia, the resident immune cells of the brain, are at the center of communication between the central nervous system and immune system. While these brain-immune interactions are balanced in healthy adulthood, the ability to maintain homeostasis during aging is impaired. Microglia develop a loss of integrated regulatory networks including aberrant signaling from other brain cells, immune sensors, and epigenetic modifiers. The low-grade chronic neuroinflammation associated with this dysfunctional activity likely contributes to cognitive deficits and susceptibility to age-related pathologies. A better understanding of the underlying mechanisms responsible for neuro-immune dysregulation with age is crucial for providing targeted therapeutic strategies to support brain repair and healthy aging. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Distinctive Sensitivity to Microgravity of Immune Cell Subpopulations

NASA Astrophysics Data System (ADS)

Chen, Hui; Luo, Haiying; Liu, Jing; Wang, Peng; Dong, Dandan; Shang, Peng; Zhao, Yong

2015-11-01

Immune dysfunction in astronauts is well documented after spaceflights. Microgravity is one of the key factors directly suppressing the function of immune system. However, it is unclear which subpopulations of immune cells including innate and adaptive immune cells are more sensitive to microgravity We herein investigated the direct effects of modeled microgravity (MMg) on different immune cells in vitro. Mouse splenocytes, thymocytes and bone marrow cells were exposed to MMg for 16 hrs. The survival and the phenotypes of different subsets of immune cells including CD4+T cells, CD8+T cells, CD4+Foxp3+ regulatory T cells (Treg), B cells, monocytes/macrophages, dendritic cells (DCs), natural killer cells (NK) were determined by flow cytometry. After splenocytes were cultured under MMg for 16h, the cell frequency and total numbers of monocytes, macrophages and CD4+Foxp3+T cells were significantly decreased more than 70 %. MMg significantly decreased the cell numbers of CD8+ T cells, B cells and neutrophils in splenocytes. The cell numbers of CD4+T cells and NK cells were unchanged significantly when splenocytes were cultured under MMg compared with controls. However, MMg significantly increased the ratio of mature neutrophils to immature neutrophils in bone marrow and the cell number of DCs in splenocytes. Based on the cell survival ability, monocytes, macrophages and CD4+Foxp3+Treg cells are most sensitive to microgravity; CD4+T cells and NK cells are resistant to microgravity; CD8+T cells and neutrophils are impacted by short term microgravity exposure. Microgravity promoted the maturation of neutrophils and development of DCs in vitro. The present studies offered new insights on the direct effects of MMg on the survival and homeostasis of immune cell subsets.

T Follicular Helper Cells and B Cell Dysfunction in Aging and HIV-1 Infection

PubMed Central

Pallikkuth, Suresh; de Armas, Lesley; Rinaldi, Stefano; Pahwa, Savita

2017-01-01

T follicular helper (Tfh) cells are a subset of CD4 T cells that provide critical signals to antigen-primed B cells in germinal centers to undergo proliferation, isotype switching, and somatic hypermutation to generate long-lived plasma cells and memory B cells during an immune response. The quantity and quality of Tfh cells therefore must be tightly controlled to prevent immune dysfunction in the form of autoimmunity and, on the other hand, immune deficiency. Both Tfh and B cell perturbations appear during HIV infection resulting in impaired antibody responses to vaccines such as seasonal trivalent influenza vaccine, also seen in biologic aging. Although many of the HIV-associated defects improve with antiretroviral therapy (ART), excess immune activation and antigen-specific B and T cell responses including Tfh function are still impaired in virologically controlled HIV-infected persons on ART. Interestingly, HIV infected individuals experience increased risk of age-associated pathologies. This review will discuss Tfh and B cell dysfunction in HIV infection and highlight the impact of chronic HIV infection and aging on Tfh–B cell interactions. PMID:29109730

T Follicular Helper Cells and B Cell Dysfunction in Aging and HIV-1 Infection.

PubMed

Pallikkuth, Suresh; de Armas, Lesley; Rinaldi, Stefano; Pahwa, Savita

2017-01-01

T follicular helper (Tfh) cells are a subset of CD4 T cells that provide critical signals to antigen-primed B cells in germinal centers to undergo proliferation, isotype switching, and somatic hypermutation to generate long-lived plasma cells and memory B cells during an immune response. The quantity and quality of Tfh cells therefore must be tightly controlled to prevent immune dysfunction in the form of autoimmunity and, on the other hand, immune deficiency. Both Tfh and B cell perturbations appear during HIV infection resulting in impaired antibody responses to vaccines such as seasonal trivalent influenza vaccine, also seen in biologic aging. Although many of the HIV-associated defects improve with antiretroviral therapy (ART), excess immune activation and antigen-specific B and T cell responses including Tfh function are still impaired in virologically controlled HIV-infected persons on ART. Interestingly, HIV infected individuals experience increased risk of age-associated pathologies. This review will discuss Tfh and B cell dysfunction in HIV infection and highlight the impact of chronic HIV infection and aging on Tfh-B cell interactions.

Genetic models in applied physiology: selected contribution: effects of spaceflight on immunity in the C57BL/6 mouse. I. Immune population distributions

NASA Technical Reports Server (NTRS)

Pecaut, Michael J.; Nelson, Gregory A.; Peters, Luanne L.; Kostenuik, Paul J.; Bateman, Ted A.; Morony, Sean; Stodieck, Louis S.; Lacey, David L.; Simske, Steven J.; Gridley, Daila S.

2003-01-01

There are several aspects of the spaceflight environment that may lead to changes in immunity: mission-related psychological stress, radiation, and changes in gravity. On December 5, 2001, the space shuttle Endeavor launched for a 12-day mission to examine these effects on C57BL/6 mice for the first time. On their return, assays were performed on the spleen, blood, and bone marrow. In response to flight, there were no significant differences in the general circulating leukocyte proportions. In contrast, there was an increase in splenic lymphocyte percentages, with a corresponding decrease in granulocytes. There was an overall shift in splenic lymphocytes away from T cells toward B cells, and a decrease in the CD4-to-CD8 ratios due to a decrease in T helpers. In contrast, there were proportional increases in bone marrow T cells, with decreases in B cells. Although the blast percentage and count were decreased in flight mice, the CD34(+) population was increased. The data were more consistent with a shift in bone marrow populations rather than a response to changes in the periphery. Many of the results are similar to those using other models. Clearly, spaceflight can influence immune parameters ranging from hematopoiesis to mature leukocyte mechanisms.

Mitochondrial dysfunction as a trigger of innate immune responses and inflammation.

PubMed

West, A Phillip

2017-11-01

A growing literature indicates that mitochondria are key participants in innate immune pathways, functioning as both signaling platforms and contributing to effector responses. In addition to regulating antiviral signaling and antibacterial immunity, mitochondria are also important drivers of inflammation caused by sterile injury. Much research on mitochondrial control of immunity now centers on understanding how mitochondrial constituents released during cellular damage simulate the innate immune system. When mitochondrial integrity is compromised, mitochondrial damage-associated molecular patterns engage pattern recognition receptors, trigger inflammation, and promote pathology in an expanding list of diseases. Here, I review the emerging knowledge of mitochondrial dysfunction in innate immune responses and discuss how environmental exposures may induce mitochondrial damage to potentiate inflammation and human disease. Copyright © 2017 Elsevier B.V. All rights reserved.

Immune changes during short-duration missions

NASA Technical Reports Server (NTRS)

Taylor, G. R.

1993-01-01

Spaceflight materially influences the immune mechanism of humans and animals. Effects resulting from missions of less than 1 month are examined. Effects from longer missions are discussed in the companion paper by Konstantinova et al. Most immunology studies have involved analyses of subjects and samples from subjects obtained after flight, with the data being compared with similar data obtained before flight. These studies have demonstrated that short-duration missions can result in a postflight depression in blast cell transformation, major changes in cytokine function, and alterations in the relative numbers of immune cell populations. In addition to these post- vs. preflight studies, some data have been produced in flight. However, these in vitro analyses have been less than satisfactory because of differences between in-flight and ground-control conditions. Recently, both the U.S. and Russian space programs have started collecting in-flight, in vivo, cell-mediated immunity data. These studies have confirmed that the human cell-mediated immune system is blunted during spaceflight.

Immune changes during short-duration missions.

PubMed

Taylor, G R

1993-09-01

Spaceflight materially influences the immune mechanism of humans and animals. Effects resulting from missions of less than 1 month are examined. Effects from longer missions are discussed in the companion paper by Konstantinova et al. Most immunology studies have involved analyses of subjects and samples from subjects obtained after flight, with the data being compared with similar data obtained before flight. These studies have demonstrated that short-duration missions can result in a postflight depression in blast cell transformation, major changes in cytokine function, and alterations in the relative numbers of immune cell populations. In addition to these post- vs. preflight studies, some data have been produced in flight. However, these in vitro analyses have been less than satisfactory because of differences between in-flight and ground-control conditions. Recently, both the U.S. and Russian space programs have started collecting in-flight, in vivo, cell-mediated immunity data. These studies have confirmed that the human cell-mediated immune system is blunted during spaceflight.

Three-Dimensional Normal Human Neutral Progenitor Tissue-Like Assemblies: A Model for Persistent Varicella-Zoster Virus Infection and Platform to Study Oxidate Stress and Damage in Multiple Hit Scenarios

NASA Technical Reports Server (NTRS)

Goodwin, Thomas J.; McCarthy, M.; Osterrieder, N.; Cohrs, R. J.; Kaufer, B. B.

2014-01-01

The environment of space results in a multitude of challenges to the human physiology that present barriers to extended habitation and exploration. Over 40 years of investigation to define countermeasures to address space flight adaptation has left gaps in our knowledge regarding mitigation strategies partly due to the lack of investigative tools, monitoring strategies, and real time diagnostics to understand the central causative agent(s) responsible for physiologic adaptation and maintaining homeostasis. Spaceflight-adaptation syndrome is the combination of space environmental conditions and the synergistic reaction of the human physiology. Our work addresses the role of oxidative stress and damage (OSaD) as a negative and contributing Risk Factor (RF) in the following areas of combined spaceflight related dysregulation: i) radiation induced cellular damage [1], [2] ii) immune impacts and the inflammatory response [3], [4] and iii) varicella zoster virus (VZV) reactivation [5]. Varicella-zoster (VZV)/Chicken Pox virus is a neurotropic human alphaherpes virus resulting in varicella upon primary infection, suppressed by the immune system becomes latent in ganglionic neurons, and reactivates under stress events to re-express in zoster and possibly shingles. Our laboratory has developed a complex three-dimensional (3D) normal human neural tissue model that emulates several characteristics of the human trigeminal ganglia (TG) and allows the study of combinatorial experimentation which addresses, simultaneously, OSaD associated with Spaceflight adaptation and habitation [6]. By combining the RFs of microgravity, radiation, and viral infection we will demonstrate that living in the space environment leads to significant physiological consequences for the peripheral and subsequently the central nervous system (PNS, CNS) associated with OSaD generation and consequentially endangers long-duration and exploration-class missions.

Field Immune Assessment during Simulated Planetary Exploration in the Canadian Arctic

NASA Technical Reports Server (NTRS)

Crucian, Brian; Lee, Pascal; Stowe, Raymond; Jones, Jeff; Effenhauser, Rainer; Widen, Raymond; Sams, Clarence

2006-01-01

Dysregulation of the immune system has been shown to occur during space flight, although the detailed nature of the phenomenon and the clinical risks for exploration class missions has yet to be established. In addition, the growing clinical significance of immune system evaluation combined with epidemic infectious disease rates in third world countries provides a strong rationale for the development of field-compatible clinical immunology techniques and equipment. In July 2002 NASA performed a comprehensive field immunology assessment on crewmembers participating in the Haughton-Mars Project (HMP) on Devon Island in the high Canadian Arctic. The purpose of the study was to evaluate mission-associated effects on the human immune system, as well as to evaluate techniques developed for processing immune samples in remote field locations. Ten HMP-2002 participants volunteered for the study. A field protocol was developed at NASA-JSC for performing sample collection, blood staining/processing for immunophenotype analysis, wholeblood mitogenic culture for functional assessments and cell-sample preservation on-location at Devon Island. Specific assays included peripheral leukocyte distribution; constitutively activated T cells, intracellular cytokine profiles and plasma EBV viral antibody levels. Study timepoints were L-30, midmission and R+60. The protocol developed for immune sample processing in remote field locations functioned properly. Samples were processed in the field location, and stabilized for subsequent analysis at the Johnson Space Center in Houston. The data indicated that some phenotype, immune function and stress hormone changes occurred in the HMP field participants that were largely distinct from pre-mission baseline and post-mission recovery data. These immune changes appear similar to those observed in Astronauts following spaceflight. The sample processing protocol developed for this study may have applications for immune assessment during exploration-class space missions or in remote terrestrial field locations. The data validate the use of the HMP as a ground-based spaceflight/planetary exploration analog for some aspects of human physiology.

Dammarane Sapogenins Ameliorates Neurocognitive Functional Impairment Induced by Simulated Long-Duration Spaceflight.

PubMed

Wu, Xiaorui; Li, Dong; Liu, Junlian; Diao, Lihong; Ling, Shukuan; Li, Yuheng; Gao, Jianyi; Fan, Quanchun; Sun, Weijia; Li, Qi; Zhao, Dingsheng; Zhong, Guohui; Cao, Dengchao; Liu, Min; Wang, Jiaping; Zhao, Shuang; Liu, Yu; Bai, Guie; Shi, Hongzhi; Xu, Zi; Wang, Jing; Xue, Chunmei; Jin, Xiaoyan; Yuan, Xinxin; Li, Hongxing; Liu, Caizhi; Sun, Huiyuan; Li, Jianwei; Li, Yongzhi; Li, Yingxian

2017-01-01

Increasing evidence indicates the occurrence of cognitive impairment in astronauts under spaceflight compound conditions, but the underlying mechanisms and countermeasures need to be explored. In this study, we found that learning and memory abilities were significantly reduced in rats under a simulated long-duration spaceflight environment (SLSE), which includes microgravity, isolation confinement, noises, and altered circadian rhythms. Dammarane sapogenins (DS), alkaline hydrolyzed products of ginsenosides, can enhance cognition function by regulating brain neurotransmitter levels and inhibiting SLSE-induced neuronal injury. Bioinformatics combined with experimental verification identified that the PI3K-Akt-mTOR pathway was inhibited and the MAPK pathway was activated during SLSE-induced cognition dysfunction, whereas DS substantially ameliorated the changes in brain. These findings defined the characteristics of SLSE-induced cognitive decline and the mechanisms by which DS improves it. The results provide an effective candidate for improving cognitive function in spaceflight missions.

Dammarane Sapogenins Ameliorates Neurocognitive Functional Impairment Induced by Simulated Long-Duration Spaceflight

PubMed Central

Wu, Xiaorui; Li, Dong; Liu, Junlian; Diao, Lihong; Ling, Shukuan; Li, Yuheng; Gao, Jianyi; Fan, Quanchun; Sun, Weijia; Li, Qi; Zhao, Dingsheng; Zhong, Guohui; Cao, Dengchao; Liu, Min; Wang, Jiaping; Zhao, Shuang; Liu, Yu; Bai, Guie; Shi, Hongzhi; Xu, Zi; Wang, Jing; Xue, Chunmei; Jin, Xiaoyan; Yuan, Xinxin; Li, Hongxing; Liu, Caizhi; Sun, Huiyuan; Li, Jianwei; Li, Yongzhi; Li, Yingxian

2017-01-01

Increasing evidence indicates the occurrence of cognitive impairment in astronauts under spaceflight compound conditions, but the underlying mechanisms and countermeasures need to be explored. In this study, we found that learning and memory abilities were significantly reduced in rats under a simulated long-duration spaceflight environment (SLSE), which includes microgravity, isolation confinement, noises, and altered circadian rhythms. Dammarane sapogenins (DS), alkaline hydrolyzed products of ginsenosides, can enhance cognition function by regulating brain neurotransmitter levels and inhibiting SLSE-induced neuronal injury. Bioinformatics combined with experimental verification identified that the PI3K-Akt-mTOR pathway was inhibited and the MAPK pathway was activated during SLSE-induced cognition dysfunction, whereas DS substantially ameliorated the changes in brain. These findings defined the characteristics of SLSE-induced cognitive decline and the mechanisms by which DS improves it. The results provide an effective candidate for improving cognitive function in spaceflight missions. PMID:28611667

Three-Dimensional Normal Human Neural Progenitor Tissue-Like Assemblies: A Model for Persistent Varicell-Zoster Virus Infection and Platform to Study Viral Infectivity and Oxidative Stress and Damage

NASA Technical Reports Server (NTRS)

Goodwin, T. J.; McCarthy, M.; Osterrieder, N.; Cohrs, R. J.; Kaufer, B. B.

2014-01-01

The environment of space results in a multitude of challenges to the human physiology that present barriers to extended habitation and exploration. Over 40 years of investigation to define countermeasures to address space flight adaptation has left gaps in our knowledge regarding mitigation strategies partly due to the lack of investigative tools, monitoring strategies, and real time diagnostics to understand the central causative agent(s) responsible for physiologic adaptation and maintaining homeostasis. Spaceflight-adaptation syndrome is the combination of space environmental conditions and the synergistic reaction of the human physiology. Our work addresses the role of oxidative stress and damage (OSaD) as a negative and contributing Risk Factor (RF) in the following areas of combined spaceflight related dysregulation: i) radiation induced cellular damage [1], [2] ii) immune impacts and the inflammatory response [3], [4] and iii) varicella zoster virus (VZV) reactivation [5]. Varicella-zoster (VZV)/Chicken Pox virus is a neurotropic human alphaherpesvirus resulting in varicella upon primary infection, suppressed by the immune system becomes latent in ganglionic neurons, and reactivates under stress events to re-express in zoster and possibly shingles. Our laboratory has developed a complex threedimensional (3D) normal human neural tissue model that emulates several characteristics of the human trigeminal ganglia (TG) and allows the study of combinatorial experimentation which addresses, simultaneously, OSaD associated with Spaceflight adaptation and habitation [6].

Parallels in Immunometabolic Adipose Tissue Dysfunction with Ageing and Obesity

PubMed Central

Trim, William; Turner, James E.; Thompson, Dylan

2018-01-01

Ageing, like obesity, is often associated with alterations in metabolic and inflammatory processes resulting in morbidity from diseases characterised by poor metabolic control, insulin insensitivity, and inflammation. Ageing populations also exhibit a decline in immune competence referred to as immunosenescence, which contributes to, or might be driven by chronic, low-grade inflammation termed “inflammageing”. In recent years, animal and human studies have started to uncover a role for immune cells within the stromal fraction of adipose tissue in driving the health complications that come with obesity, but relatively little work has been conducted in the context of immunometabolic adipose function in ageing. It is now clear that aberrant immune function within adipose tissue in obesity—including an accumulation of pro-inflammatory immune cell populations—plays a major role in the development of systemic chronic, low-grade inflammation, and limiting the function of adipocytes leading to an impaired fat handling capacity. As a consequence, these changes increase the chance of multiorgan dysfunction and disease onset. Considering the important role of the immune system in obesity-associated metabolic and inflammatory diseases, it is critically important to further understand the interplay between immunological processes and adipose tissue function, establishing whether this interaction contributes to age-associated immunometabolic dysfunction and inflammation. Therefore, the aim of this article is to summarise how the interaction between adipose tissue and the immune system changes with ageing, likely contributing to the age-associated increase in inflammatory activity and loss of metabolic control. To understand the potential mechanisms involved, parallels will be drawn to the current knowledge derived from investigations in obesity. We also highlight gaps in research and propose potential future directions based on the current evidence. PMID:29479350

Gene-metabolite profile integration to understand the cause of spaceflight induced immunodeficiency.

PubMed

Chakraborty, Nabarun; Cheema, Amrita; Gautam, Aarti; Donohue, Duncan; Hoke, Allison; Conley, Carolynn; Jett, Marti; Hammamieh, Rasha

2018-01-01

Spaceflight presents a spectrum of stresses very different from those associated with terrestrial conditions. Our previous study (BMC Genom. 15 : 659, 2014) integrated the expressions of mRNAs, microRNAs, and proteins and results indicated that microgravity induces an immunosuppressive state that can facilitate opportunistic pathogenic attack. However, the existing data are not sufficient for elucidating the molecular drivers of the given immunosuppressed state. To meet this knowledge gap, we focused on the metabolite profile of spaceflown human cells. Independent studies have attributed cellular energy deficiency as a major cause of compromised immunity of the host, and metabolites that are closely associated with energy production could be a robust signature of atypical energy fluctuation. Our protocol involved inoculation of human endothelial cells in cell culture modules in spaceflight and on the ground concurrently. Ten days later, the cells in space and on the ground were exposed to lipopolysaccharide (LPS), a ubiquitous membrane endotoxin of Gram-negative bacteria. Nucleic acids, proteins, and metabolites were collected 4 and 8 h post-LPS exposure. Untargeted profiling of metabolites was followed by targeted identification of amino acids and knowledge integration with gene expression profiles. Consistent with the past reports associating microgravity with increased energy expenditure, we identified several markers linked to energy deficiency, including various amino acids such as tryptophan, creatinine, dopamine, and glycine, and cofactors such as lactate and pyruvate. The present study revealed a molecular architecture linking energy metabolism and immunodeficiency in microgravity. The energy-deficient condition potentially cascaded into dysregulation of protein metabolism and impairment of host immunity. This project is limited by a small sample size. Although a strict statistical screening was carefully implemented, the present results further emphasize the need for additional studies with larger sample sizes. Validating this hypothesis using an in vivo model is essential to extend the knowledge towards identifying markers of diagnostic and therapeutic value.

The natural cytotoxicity in cosmonauts on board space stations

NASA Astrophysics Data System (ADS)

Meshkov, D.; Rykova, M.

The nature of the changes of resistance to infection seems to be very important. Our studies indicate that different functions of natural killers could be depressed after the spaceflight. The decrease of the percentage of the lymphocytes that can bind target cells lead to the lowering of the "active" NK level and this can be resulted in the depression of total NK activity and lowering of resistance to viral and tumor antigens. The investigation of natural killer cells in cosmonauts before and after short and long-term spaceflights also revealed the important role of spaceflight duration, stress and individual immune reactivity.

The TCAR Report: Translational Cell and Animal Research Space (1965-2011) Sponsored by NASA Ames Research Center

NASA Technical Reports Server (NTRS)

Ronca, A. E.; Mains, Richard; Alwood, J. S.; French, A. J.; Smith, J. D.; Miller, Virginia; Tash, Joseph; Jenkins, Marjorie

2015-01-01

Five decades ago, NASA Ames Research Center (ARC) began a vigorous program of space biology research utilizing animal cells, tissues and whole organisms. Since its inception, this program has yielded exciting new insights into how spaceflight influences fundamental processes of living systems. These are findings with important translational implications for human health in space and on Earth. The TCAR Report is a compilation of 394 flight experiments conducted across the period spanning 1965 - 2011 with individual chapters devoted to: (1) Bone Physiology, (2) Cardiovascular/Cardiopulmonary Physiology, (3) Developmental Biology, (4) Immunology, (5) Microbial Growth and Virulence, (6) Muscle Physiology, (7) Neurophysiology and (8) Regulatory Physiology. Specialists in those disciplines reviewed the research and each prepared an overview including the translational relevance of the findings for human health in space and on Earth. The Report will be made available in early 2015 through standard NASA publication resources and on the NASA Life Sciences Data Archive (http://lsda.jsc.nasa.gov/lsda_home1.aspx). The LSDA can be mined for detailed information, including Experiment, Mission, Available Biospecimens, Document, Hardware, Dataset, Personnel, and includes a searchable Photo Gallery. Space biology translational topic highlights include: Inflight centrifugation protection of bone strength losses; Assessment of evidence related to visual impairment in astronauts; Mammalian development including vestibular system plasticity and vestibular-visual integration; Verification of limb unloading ground-based studies as a model for spaceflight unloading; Immune system impairment and increased microbiological virulence aligned with immune dysfunction; and Rapid bone and muscle tissue and functional losses associated with unloading. In addition to astronauts, these results may help humans on Earth, by providing insight into the definition of fundamental mechanisms and potential treatments for debilitating changes that result from human aging and disease. The TCAR effort has resulted in significant new insights. Modern tools now widely available for "Omics" research with model organisms and humans provide new opportunities for translational research. Omics research at various levels is greatly complemented by studies at the tissue and organismal levels. Key discoveries can occur at either the basic research or the health surveillance level such as vision problems observed in astronauts stimulating studies of eye tissues in rodents that identified relevant changes. The Ames Biospecimen Sharing Program (BSP), serving the NASA Space Biology and HRP programs, was created to maximize utilization and scientific return from unique animal specimens derived from rare, complex and costly NASA spaceflight and ground-based analog experiments. The BSP is a valuable tool for advancing translational science at NASA. Dynamic methods for tracking translational linkages across NASA space life sciences and medicine are strongly encouraged for translational science.

Hyperoxia Inhibits T Cell Activation in Mice

NASA Astrophysics Data System (ADS)

Hughes-Fulford, M.; Meissler, J.; Aguayo, E. T.; Globus, R.; Aguado, J.; Candelario, T.

2013-02-01

Background: The immune response is blunted in mice and humans in spaceflight. The effects of hyperoxia in mice alter expression of some of the same immune response genes. If these two conditions are additive, there could be an increased risk of infection in long duration missions. Immunosuppression is seen in healthy astronauts who have flown in space; however little is known about the mechanisms that cause the reduced immunity in spaceflight. Here we examine the role of oxidative stress on mice exposed to periods of high O2 levels mimicking pre-breathing protocols and extravehicular activity (EVA). To prevent decompression sickness, astronauts are exposed to elevated oxygen (hyperoxia) before and during EVA activities. Spaceflight missions may entail up to 24 hours of EVA per crewmember per week to perform construction and maintenance tasks. The effectiveness and success of these missions depends on designing EVA systems and protocols that maximize human performance and efficiency while minimizing health and safety risks for crewmembers. To our knowledge, no studies have been conducted on the immune system under 100% oxygen exposures to determine the potential for immune compromise due to prolonged and repeated EVAs. Methods: Animals were exposed to hyperoxic or control conditions for 8 hours per day over a period of 3 days, initiated 4 hours into the dark cycle (12h dark/12h light), using animal environmental control cabinets and oxygen controller (Biospherix, Lacona, NY). Experimental mice were exposed to 98-100% oxygen as a model for pre-breathing and EVA conditions, while control mice were maintained in chambers supplied with compressed air. These are ground control studies where we use real-time RTPCR (qRTPCR) to measure gene expression of the early immune gene expression during bead activation of splenocytes of normoxic and hyperoxic mice. All procedures were reviewed and approved by the IACUC at Ames Research Center. After the last 8h of hyperoxic exposure, spleens were removed and the splenocytes were isolated and kept as individual biological samples. We have also examined transcription factors (JASPAR) and pathways of the immune system to help us understand the mechanism of regulation. Results: Our recent mouse immunology experiment aboard STS-131 suggests that the early T cell immune response was inhibited in animals that have been exposed to spaceflight, even 24 hours after return to earth. Moreover, recent experiments in hyperoxic mice show that many of the same genes involved in early T cell activation were altered. Specifically, expression of IL-2Rα, Cxcl2, TNFα, FGF2, LTA and BCL2 genes are dysregulated in mice exposed to hyperoxia. Conclusions: If these hyperoxia-induced changes of gene expression in early T cell activation are additive to the changes seen in the microgravity of spaceflight, there could be an increased infection risk to EVA astronauts, which should be addressed prior to conducting a Mars or other long-term mission.

Periodontal disease as a potential factor of migraine chronification.

PubMed

Ameijeira, Pablo; Leira, Yago; Blanco, Juan; Leira, Rogelio

2017-05-01

Migraine is a hereditary constitutional base disorder, which is characterized by recurrent episodes of headache pulsatile characteristics associated with photophobia/phonophobia, nausea and/or vomiting. The main complication in migraine is the chronicity of the process, now recognized as a chronic migraine. Although pathogenic mechanisms that may influence the pathophysiology of migraine and its possible chronicity are not fully understood, previous studies have shown in patients with migraine molecular alterations of systemic inflammation, neurogenic inflammation, endothelial dysfunction, innate immunity, dysfunction of matrix proteases and blood-brain barrier. Periodontal disease is an inflammatory lesion caused by bacteria. After the bacterial infection begins, an immune response that will be responsible for individual susceptibility appears. More advanced forms of periodontitis have demonstrated molecular alterations of inflammation, endothelial dysfunction, dysfunction of matrix proteases and innate immunity, similar to those observed in migraine. Furthermore, the main molecular mediators of neurogenic inflammation related to activation of the trigeminovascular system, which are characteristic of migraine, are overexpressed in gingival crevicular fluid and mucosa in patients with periodontal disease. Hypertension, hypercholesterolemia, insulin resistance, stroke or coronary artery disease are comorbidities that periodontal disease and migraine could share. Therefore, several mechanisms and hypotheses could explain the possible association between both diseases. However, epidemiological and molecular studies will be necessary to provide a better understanding of this potential association, which could be implicated in the chronification of migraine. Copyright © 2017 Elsevier Ltd. All rights reserved.

Neuroinflamm-aging and neurodegenerative diseases: an overview.

PubMed

Pizza, Vincenzo; Agresta, Anella; D'Acunto, Cosimo W; Festa, Michela; Capasso, Anna

2011-08-01

Neuroinflammation is considered a chronic activation of the immune response in the central nervous system (CNS) in response to different injuries. This brain immune activation results in various events: circulating immune cells infiltrate the CNS; resident cells are activated; and pro-inflammatory mediators produced and released induce neuroinflammatory brain disease. The effect of immune diffusible mediators on synaptic plasticity might result in CNS dysfunction during neuroinflammatory brain diseases. The CNS dysfunction may induce several human pathological conditions associated with both cognitive impairment and a variable degree of neuroinflammation. Furthermore, age has a powerful effect on enhanced susceptibility to neurodegenerative diseases and age-dependent enhanced neuroinflammatory processes may play an important role in toxin generation that causes death or dysfunction of neurons in neurodegenerative diseases This review will address current understanding of the relationship between ageing, neuroinflammation and neurodegenerative disease by focusing on the principal mechanisms by which the immune system influences the brain plastic phenomena. Also, the present review considers the principal human neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, multiple sclerosis and psychiatric disorders caused by aging and neuroinflammation.

Mechanical Unloading of Mouse Bone in Microgravity Significantly Alters Cell Cycle Gene Set Expression

NASA Astrophysics Data System (ADS)

Blaber, Elizabeth; Dvorochkin, Natalya; Almeida, Eduardo; Kaplan, Warren; Burns, Brnedan

2012-07-01

Spaceflight factors, including microgravity and space radiation, have many detrimental short-term effects on human physiology, including muscle and bone degradation, and immune system dysfunction. The long-term progression of these physiological effects is still poorly understood, and a serious concern for long duration spaceflight missions. We hypothesized that some of the degenerative effects of spaceflight may be caused in part by an inability of stem cells to proliferate and differentiate normally resulting in an impairment of tissue regenerative processes. Furthermore, we hypothesized that long-term bone tissue degeneration in space may be mediated by activation of the p53 signaling network resulting in cell cycle arrest and/or apoptosis in osteoprogenitors. In our analyses we found that spaceflight caused significant bone loss in the weight-bearing bones of mice with a 6.3% reduction in bone volume and 11.9% decrease in bone thickness associated with increased osteoclastic activity. Along with this rapid bone loss we also observed alterations in the cell cycle characterized by an increase in the Cdkn1a/p21 cell cycle arrest molecule independent of Trp53. Overexpression of Cdkn1a/p21 was localized to osteoblasts lining the periosteal surface of the femur and chondrocytes in the head of the femur, suggesting an inhibition of proliferation in two key regenerative cell types of the femur in response to spaceflight. Additionally we found overexpression of several matrix degradation molecules including MMP-1a, 3 and 10, of which MMP-10 was localized to osteocytes within the shaft of the femur. This, in conjunction with 40 nm resolution synchrotron nano-Computed Tomography (nano-CT) observations of an increase in osteocyte lacunae cross-sectional area, perimeter and a decrease in circularity indicates a potential role for osteocytic osteolysis in the observed bone degeneration in spaceflight. To further investigate the genetic response of bone to mechanical unloading in spaceflight, we conducted genome wide microarray analysis of total RNA isolated from the mouse pelvis. Specifically, 16 week old mice were subjected to 15 days spaceflight onboard NASA's STS-131 space shuttle mission. The pelvis of the mice was dissected, the bone marrow was flushed and the bones were briefly stored in RNAlater. The pelvii were then homogenized, and RNA was isolated using TRIzol. RNA concentration and quality was measured using a Nanodrop spectrometer, and 0.8% agarose gel electrophoresis. Samples of cDNA were analyzed using an Affymetrix GeneChip\\S Gene 1.0 ST (Sense Target) Array System for Mouse and GenePattern Software. We normalized the ST gene arrays using Robust Multichip Average (RMA) normalization, which summarizes perfectly matched spots on the array through the median polish algorithm, rather than normalizing according to mismatched spots. We also used Limma for statistical analysis, using the BioConductor Limma Library by Gordon Smyth, and differential expression analysis to identify genes with significant changes in expression between the two experimental conditions. Finally we used GSEApreRanked for Gene Set Enrichment Analysis (GSEA), with Kolmogorov-Smirnov style statistics to identify groups of genes that are regulated together using the t-statistics derived from Limma. Preliminary results show that 6,603 genes expressed in pelvic bone had statistically significant alterations in spaceflight compared to ground controls. These prominently included cell cycle arrest molecules p21, and p18, cell survival molecule Crbp1, and cell cycle molecules cyclin D1, and Cdk1. Additionally, GSEA results indicated alterations in molecular targets of cyclin D1 and Cdk4, senescence pathways resulting from abnormal laminin maturation, cell-cell contacts via E-cadherin, and several pathways relating to protein translation and metabolism. In total 111 gene sets out of 2,488, about 4%, showed statistically significant set alterations. These alterations indicate significant impairment of normal cellular function in the mechanically unloaded environment of space and could provide important genetic insight into the observed uncoupling of bone formation and resorption in space.

Immune response to 60-day head-down bed rest

NASA Astrophysics Data System (ADS)

Song, Jinping; Guo, Aihua; Zhong, Ping; Zhang, Hongyu; Wu, Feng; Wan, Yumin; Bai, Yanqiang; Chen, Shanguang; Li, Yinghui

Introduction: Exposure of humans to spaceflight has resulted in disregulation of the immune system. Head-down bed rest (HDBR) has been extensively used as an earth-bound analog to study physiologic effects mimicking those occurring in weightlessness during spaceflight. It is uncertain how a prolonged period of bed rest affect human immune responses. The objective of this study was to investigate the effects of 60-day HDBR on immune function and EB virus reactivation in seven male volunteers. Methods: There were seven healthy male volunteers who were subjected to HDBR for 60d. Immunological parameters including leukocyte subset distribution, lymphocyte proliferation to mitogens, secreted cytokine profiles and EB virus reactivation were monitored. Results: Total WBC conunts increased significantly 10d post-HDBR as compared with pre-HDBR. At the same time, the relative percentage of neutrophils was also higher than pre-HDBR but not significant. MFI of CD11b in neutrophils was reduced obviously at thd end of HDBR. T Lymphocyte proliferations to PHA reduced at HDBR 30, HDBR 60 and 10d post-HDBR while IL-2 production decreased significantly at the same time. IFN-and IL-4 production trended to decrease at HDBR 30 and HDBR 60. The relative percentage of T lymphocyte subset, B lymphocyte and NK cells were not altered. EBV EA (early antigen) were negative and EBV VCA titers had no changes through HDBR. Conclusion: The results indicate that several immunological parameters (mainly cellular immunity) are altered significantly by prolonged HDBR, and these changes were similar to those happened in spaceflight.

Clinical Herpes Zoster in Antarctica as a Model for Spaceflight.

PubMed

Reyes, David P; Brinley, Alaina A; Blue, Rebecca S; Gruschkus, Stephen K; Allen, Andrew T; Parazynski, Scott E

2017-08-01

Antarctica is a useful analog for spaceflight, as both environments are remote, isolated, and with limited resources. While previous studies have demonstrated increased asymptomatic viral shedding in both the Antarctic and spaceflight environments, clinical manifestations of reactivated viral disease have been less frequently identified. We sought to identify the incidence of clinical herpes zoster from viral reactivation in the Antarctic winter-over population. Medical records from the 2014 winter season were reviewed for the incidence of zoster in U.S. Antarctic personnel and then compared to the age-matched U.S. Five cases of clinical herpes zoster occurred in the Antarctic Station population of 204 persons, for an incidence of 33.3 per 1000 person-years vs. 3.2 per 1000 person-years in the general population. Four cases were in persons under age 40, yielding an incidence of 106.7 per 1000 person-years in persons ages 30-39 compared to an incidence of 2.0 per 1000 person-years in the same U.S. age group. Immune suppression due to the stressful Antarctic environment may have contributed to the increased incidence of herpes zoster in U.S. Antarctic personnel during the winter of 2014. Working and living in isolated, confined, and extreme environments can cause immune suppression, reactivating latent viruses and increasing viral shedding and symptomatic disease. Such changes have been observed in other austere environments, including spaceflight, suggesting that clinical manifestations of viral reactivation may be seen in future spaceflight.Reyes DP, Brinley AA, Blue RS, Gruschkus SK, Allen AT, Parazynski SE. Clinical herpes zoster in Antarctica as a model for spaceflight. Aerosp Med Hum Perform. 2017; 88(8):784-788.

Immune Response and Function: Exercise Conditioning Versus Bed-Rest and Spaceflight Deconditioning

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.; Jackson, C. G. R.; Lawless, D.

1994-01-01

Immune responses measured at rest immediately or some hours after exercise training (some with and some without increase in maximal oxygen uptake) gave variable and sometimes conflicting results; therefore, no general conclusions can be drawn. On the other hand, most immune responses were either unchanged (immunoglobulin, T cells, CD4+, and natural killer activity) or decreased (blood properdin, neutrophil phagocytic activity, salivary lysozymes, brain immunoglobulin A and G, and liver B lymphocytes and phytohemagglutinin activity) during prolonged bed rest. Some data suggested that exercise training during bed rest may partially ameliorate the decreased functioning of the immune system. Exercise and change in body position, especially during prolonged bed rest with plasma fluid shifts and diuresis, may induce a change in plasma protein concentration and content, which can influence drug metabolism as well as immune function. Leukocytosis, accompanied by lymphopenia and a depressed lymphocyte response, occurs in astronauts on return to Earth from spaceflight; recovery may depend on time of exposure to microgravity. It is clear that the effect of drugs and exercise used as countermeasures for microgravity deconditioning should be evaluated for their effect on an astronaut's immune system to assure optimal health and performance on long-duration space missions.

Post-Spaceflight (STS-135) Mouse Splenocytes Demonstrate Altered Activation Properties and Surface Molecule Expression

PubMed Central

Crucian, Brian; Sams, Clarence

2015-01-01

Alterations in immune function have been documented during or post-spaceflight and in ground based models of microgravity. Identification of immune parameters that are dysregulated during spaceflight is an important step in mitigating crew health risks during deep space missions. The in vitro analysis of leukocyte activity post-spaceflight in both human and animal species is primarily focused on lymphocytic function. This report completes a broader spectrum analysis of mouse lymphocyte and monocyte changes post 13 days orbital flight (mission STS-135). Analysis includes an examination in surface markers for cell activation, and antigen presentation and co-stimulatory molecules. Cytokine production was measured after stimulation with T-cell mitogen or TLR-2, TLR-4, or TLR-5 agonists. Splenocyte surface marker analysis immediate post-spaceflight and after in vitro culture demonstrated unique changes in phenotypic populations between the flight mice and matched treatment ground controls. Post-spaceflight splenocytes (flight splenocytes) had lower expression intensity of CD4+CD25+ and CD8+CD25+ cells, lower percentage of CD11c+MHC II+ cells, and higher percentage of CD11c+MHC I+ populations compared to ground controls. The flight splenocytes demonstrated an increase in phagocytic activity. Stimulation with ConA led to decrease in CD4+ population but increased CD4+CD25+ cells compared to ground controls. Culturing with TLR agonists led to a decrease in CD11c+ population in splenocytes isolated from flight mice compared to ground controls. Consequently, flight splenocytes with or without TLR-agonist stimulation showed a decrease in CD11c+MHC I+, CD11c+MHC II+, and CD11c+CD86+ cells compared to ground controls. Production of IFN-γ was decreased and IL-2 was increased from ConA stimulated flight splenocytes. This study demonstrated that expression of surface molecules can be affected by conditions of spaceflight and impaired responsiveness persists under culture conditions in vitro. PMID:25970640

Humoral and cellular immunity in cosmonauts after the ISS missions

NASA Astrophysics Data System (ADS)

Rykova, M. P.; Antropova, E. N.; Larina, I. M.; Morukov, B. V.

Spaceflight effects on the immune system were studied in 30 cosmonauts flown onto the International Space Station (ISS) for long- (125-195 d, n=15) and short-term (8-10 d, n=15) missions. Immunological investigations before launch and after landing were performed by using methods for quantitative and functional evaluation of the immunologically competent cells. Specific assays include: peripheral leukocyte distribution, natural killer (NK) cell cytotoxic activity, phagocytic activity of monocytes and granulocytes, proliferation of T-cells in response to a mitogen, levels of immunoglobulins IgA, IgM, IgG, virus-specific antibody and cytokine in serum. It was noticed that after long-term spaceflights the percentage of NK (CD3-/CD16+/CD56+) cells was significantly reduced compared with pre-flight data (p<0.05) and NK activity was suppressed by 20-85% as compared with pre-flight data in 12 out of 15 cosmonauts. T-lymphocyte activity was decreased by 25-39% as compared with pre-flight data in 5 out of 13 cosmonauts. However, the relative number of CD3+, CD4+ and CD8+ T-cells did not change. The functional activity of NK and T-cells decreased in some of the cosmonauts after short-term missions. On the other hand, a moderate trend upward of NK cytotoxic activity and proliferative activity of T-cells was observed in some individuals. Concentrations immunoglobulins (IgA, IgM, IgG) and levels of M and G antibodies to herpes simplex virus (HSV), cytomegalovirus (CMV), Epstein-Barr virus (EBV) and herpes virus type 6 (HV6) in serum did not reveal significant changes after long- and short-term flights. Concentrations of cytokines (IL- 1β, IL-2, IL-4 and TNF- α) in serum changed in an apparently random manner as compared with values before long- and short-term missions. Despite the fact that many improvements have been made to the living conditions of aboard the ISS our investigations demonstrate the remarkable depression of the immunological function after the ISS missions. These results suggest that the clinical health risk (related to immune dysfunction) will occur during exploration class missions.

Experimental Modification of Rat Pituitary Prolactin Cell Function During and After Spaceflight

NASA Technical Reports Server (NTRS)

Hymer, W. C.; Salada, T.; Avery, L.; Grindeland, R. E.

1996-01-01

Experimental modification of rat pituitary prolactin cell function during and after spaceflight. This study was done to evaluate the effects of microgravity on prolactin (PRL) cells of the male rat pituitary gland. We used the identical passive closed-vial cell culture system that was described for the culture of growth hormone cells (W C. Hymer, R. E. Grindeland, T. Salada, P. Nye, E. Grossman, and R Lane). After an 8-day spaceflight, all flight media (containing released PRL), as well as extracts (containing intracellular PRL), contained significantly lower amounts of immunoreactive PRL than their corresponding ground control samples. On the other hand, these same samples, when assessed for their biological activities by two different in vitro lymphocyte assays, yielded disparate results that may reflect posttranslational modifications to the hormone molecule. Other data showed that: (1) the apparent molecular weights of released PRL molecules were not altered by microgravity; but (2) the region from which the PRL cells came (dorsal or ventral) made a significant difference in the amount and activity of PRL released from the flight cells. Because there is much current interest in the role that PRL may play in the regulation of the immune system and because changes in both cellular and humoral immunity accompany spaceflight, this study could help define future microgravity research in this area.

Triactome: neuro-immune-adipose interactions. Implication in vascular biology.

PubMed

Chaldakov, George Nikov; Fiore, Marco; Ghenev, Peter I; Beltowski, Jerzy; Ranćić, Gorana; Tunçel, Neşe; Aloe, Luigi

2014-01-01

Understanding how the precise interactions of nerves, immune cells, and adipose tissue account for cardiovascular and metabolic biology is a central aim of biomedical research at present. A long standing paradigm holds that the vascular wall is composed of three concentric tissue coats (tunicae): intima, media, and adventitia. However, large- and medium-sized arteries, where usually atherosclerotic lesions develop, are consistently surrounded by periadventitial adipose tissue (PAAT), we recently designated tunica adiposa (in brief, adiposa like intima, media, and adventitia). Today, atherosclerosis is considered an immune-mediated inflammatory disease featured by endothelial dysfunction/intimal thickening, medial atrophy, and adventitial lesions associated with adipose dysfunction, whereas hypertension is characterized by hyperinnervation-associated medial thickening due to smooth muscle cell hypertrophy/hyperplasia. PAAT expansion is associated with increased infiltration of immune cells, both adipocytes and immunocytes secreting pro-inflammatory and anti-inflammatory (metabotrophic) signaling proteins collectively dubbed adipokines. However, the role of vascular nerves and their interactions with immune cells and paracrine adipose tissue is not yet evaluated in such an integrated way. The present review attempts to briefly highlight the findings in basic and translational sciences in this area focusing on neuro-immune-adipose interactions, herein referred to as triactome. Triactome-targeted pharmacology may provide a novel therapeutic approach in cardiovascular disease.

Effects of high-orbit spaceflight on signaling cascades and apoptosis in immune cells from mice flied on board the BION-M1 satellite

NASA Astrophysics Data System (ADS)

Novoselova, Elena; Shenkman, Boris; Lunin, Sergey; Parfenyuk, Svetlana; Novoselova, Tatyana; Fesenko, Eugeny

The study was designed to evaluate immune cell activity in male C57bl mice after a 30-day high-orbit spaceflight (550 km, higher than conventional manned spaceflights) on board the BION-M1 satellite (Roskosmos Program, Russia). For the present study, thymus, spleens and plasma samples were collected from mice 12 h after landing and, additionally, 7 days subsequently. Assessing the activity of NF-kappaB signaling cascade by measuring Rel A (p65) protein phosphorylation in splenic lymphocytes, we showed that the NF-kappaB activity was significantly increased at 12 h after landing. Contrariwise, one week after landing, the NF-kappaB activity was markedly decreased, even below to the control values. Interestingly, after landing there were no significant changes in SAPK/JNK cascade activity in splenic lymphocytes as well as in the expression of transcription factor IRF3 in thymus cells. To assess the apoptosis status in thymus lymphocytes, levels of p53 protein and its phosphorylated form were measured in thymic lymphocytes. It is known that p53 plays an important role in the cellular response to DNA damage, genomic aberrations, and other characteristic of apoptosis. The results showed that the high-orbit spaceflight environment caused some increase in level of p53 protein, but most notably, activated phosphorylated form of p53 protein. Calculated ratio of active and inactive forms of the protein (ph-p53/p53) 12 h after landing increased by more than 2-fold, indicating the apparent induction of apoptosis in thymus cells. Interestingly, 7 days after the landing, this ratio was not restored, but rather increased: the specified ratio was 4 times higher as compared to the ground-based control. We can conclude that response to the prolonged high-orbit spaceflight is not like the classic "stress response", which is usually observed under various stressful factors. It is known that the stress response is surely accompanied by increased SAPK/JNK cascade activity as well as the expression of the IRF3; in fact, we did not observed any changes in the SAPK/JNK phosphorylation or in the IRF3 production. Furthermore, stressful factors usually result in the fast, but reversible, thymus involution. But our measurements showed that the thymus depletion at 7th day after landing was expressed even more than 12 h after the spaceflight. This is consistent with the results of the level of apoptosis in thymus cells; indeed, the apoptosis in thymus lymphocytes 7 days after was higher than 12 h after landing. Collectively, these results indicate that the changes of immune cell homeostasis may be a result of exposure to damaging factors of not very high intensity. In any case, similar effects are caused, to our knowledge, by low doses of ionizing radiation. As spaceflight is not accompanied only with the gravitational changes, but also with other factors, such as radiation, it is possible that immune disbalance after spaceflight was caused by a combined action of several factors. The work was supported by the Russian Foundation for Basic Research, project 12-04-00113-a.The authors express their gratitude to unified team involved in preparation and implementation of the spaceflight of BION-M #1.

Immune System Dysfunction in the Elderly.

PubMed

Fuentes, Eduardo; Fuentes, Manuel; Alarcón, Marcelo; Palomo, Iván

2017-01-01

Human aging is characterized by both physical and physiological frailty that profoundly affects the immune system. In this context aging is associated with declines in adaptive and innate immunity established as immunosenescence. Immunosenescence is a new concept that reflects the age-associated restructuring changes of innate and adaptive immune functions. Thus elderly individuals usually present chronic low-level inflammation, higher infection rates and chronic diseases. A study of alterations in the immune system during aging could provide a potentially useful biomarker for the evaluation of immune senescence treatment. The immune system is the result of the interplay between innate and adaptive immunity, yet the impact of aging on this function is unclear. In this article the function of the immune system during aging is explored.

Overactivation of Mitogen-Activated Protein Kinase and Suppression of Mitofusin-2 Expression Are Two Independent Events in High Mobility Group Box 1 Protein–Mediated T Cell Immune Dysfunction

PubMed Central

Tang, Lu-ming; Zhao, Guang-ju; Zhu, Xiao-mei; Dong, Ning; Yu, Yan

2013-01-01

High mobility group box 1 protein (HMGB1), a critical proinflammatory cytokine, has recently been identified to be an immunostimulatory signal involved in sepsis-related immune dysfunction when released extracellularly, but the potential mechanism involved remains elusive. Here, we showed that the treatment with HMGB1 in vitro inhibited T lymphocyte immune response and expression of mitofusin-2 (Mfn-2; a member of the mitofusin family) in a dose- and time-dependent manner. Upregulation of Mfn-2 expression attenuated the suppressive effect of HMGB1 on T cell immune function. The phosphorylation of both extracellular signal-regulated kinase (ERK)1/2 and p38 mitogen-activated protein kinase (MAPK) was markedly upregulated by treating with high amount of HMGB1, while pretreatment with ERK1/2 and p38 MAPK-specific inhibitors (U0126 and SB203580) could attenuate suppression of T cell immune function and nuclear factor of activated T cell (NFAT) activation induced by HMGB1, respectively. HMGB1-induced activity of ERK1/2 and p38 was not fully inhibited in the presence of U0126 or SB203580. Interestingly, overexpression of Mfn-2 had no marked effect on HMGB1-mediated activation of MAPK, but could attenuate the suppressive effect of HMGB1 on the activity of NFAT. Thus, the mechanisms involved in HMGB1-induced T cell immune dysfunction in vitro at least partly include suppression of Mfn-2 expression, overactivation of ERK1/2, p38 MAPK, and intervention of NFAT activation, while the protective effect of Mfn-2 on T cell immune dysfunction induced by HMGB1 is dependent on other signaling pathway associated with NFAT, but not MAPK. Taken together, we conclude that overactivation of MAPK and suppression of Mfn-2 expression are two independent events in HMGB1-mediated T cell immune dysfunction. PMID:23697559

The choreography of neuroinflammation in Huntington’s disease

PubMed Central

Crotti, Andrea; Glass, Christopher K.

2016-01-01

Currently, the concept of ‘neuroinflammation’ includes inflammation associated with neurodegenerative diseases, in which there is little or no infiltration of blood-derived immune cells into the brain. The roles of brain-resident and peripheral immune cells in these inflammatory settings are poorly understood, and it is unclear whether neuroinflammation results from immune reaction to neuronal dysfunction/degeneration, and/or represents cell-autonomous phenotypes of dysfunctional immune cells. Here, we review recent studies examining these questions in the context of Huntington’s disease (HD), where mutant Huntingtin (HTT) is expressed in both neurons and glia. Insights into the cellular and molecular mechanisms underlying neuroinflammation in HD may provide a better understanding of inflammation in more complex neurodegenerative disorders, and of the contribution of the neuroinflammatory component to neurodegenerative disease pathogenesis. PMID:26001312

[Endothelial dysfunction and nonspecific immune reactions in development and progression of osteoarthrosis in women engaged into manual work].

PubMed

Maliutina, N N; Nevzorova, M S

2015-01-01

The article considers mechanisms of development and progression of osteoarthrosis as an occupationally conditioned disease in women of manual work. Women working in physical overstrain conditions are under occupational risk with dysfunction of many body systems. The authors set a hypothesis on association of endothelial dysfunction markers dysbalance and structural remodelling of cartilage matrix as a proof of degenerative changes.

Molecular aspects of stress-gene regulation during spaceflight

NASA Technical Reports Server (NTRS)

Paul, Anna-Lisa; Ferl, Robert J.

2002-01-01

Spaceflight-associated stress has been the topic of investigation since the first terrestrial organisms were exposed to this unique environment. Organisms that evolved under the selection pressures of earth-normal environments can perceive spaceflight as a stress, either directly because gravity influences an intrinsic biological process, or indirectly because of secondary effects imparted by spaceflight upon environmental conditions. Different organisms and even different organs within an organism adapt to a spaceflight environment with a diversity of tactics. Plants are keenly sensitive to gravity for directed development, and are also sensitive to other stresses associated with closed-system spaceflight environments. Within the past decade, the tools of molecular biology have begun to provide a sophisticated evaluation of spaceflight-associated stress and the genetic responses that accompany metabolic adaptation to spaceflight.

Myeloid dendritic cells frequencies are increased in children with autism spectrum disorder and associated with amygdala volume and repetitive behaviors

PubMed Central

Breece, Elizabeth; Paciotti, Brian; Nordahl, Christine Wu; Ozonoff, Sally; Van de Water, Judy A.; Rogers, Sally J.; Amaral, David; Ashwood, Paul

2012-01-01

The pathophysiology of Autism Spectrum Disorder (ASD) is not yet known; however, studies suggest that dysfunction of the immune system affects many children with ASD. Increasing evidence points to dysfunction of the innate immune system including activation of microglia and perivascular macrophages, increases in inflammatory cytokines/chemokines in brain tissue and CSF, and abnormal peripheral monocyte cell function. Dendritic cells are major players in innate immunity and have important functions in the phagocytosis of pathogens or debris, antigen presentation, activation of naïve T cells, induction of tolerance and cytokine/chemokine production. In this study, we assessed circulating frequencies of myeloid dendritic cells (defined as Lin-1−BDCA1+CD11c+ and Lin-1−BDCA3+CD123−) and plasmacytoid dendritic cells (Lin-1− BDCA2+CD123+ or Lin-1−BDCA4+ CD11c−) in 57 children with ASD, and 29 typically developing controls of the same age, all of who were enrolled as part of the Autism Phenome Project (APP). The frequencies of dendritic cells and associations with behavioral assessment and MRI measurements of amygdala volume were compared in the same participants. The frequencies of myeloid dendritic cells were significantly increased in children with ASD compared to typically developing controls (p < 0.03). Elevated frequencies of myeloid dendritic cells were positively associated with abnormal right and left amygdala enlargement, severity of gastrointestinal symptoms and increased repetitive behaviors. The frequencies of plasmacytoid dendritic cells were also associated with amygdala volumes as well as developmental regression in children with ASD. Dendritic cells play key roles in modulating immune responses and differences in frequencies or functions of these cells may result in immune dysfunction in children with ASD. These data further implicate innate immune cells in the complex pathophysiology of ASD. PMID:23063420

Pomegranate extract and exercise provide additive benefits on improvement of immune function by inhibiting inflammation and oxidative stress in high-fat-diet-induced obesity in rats.

PubMed

Zhao, Fei; Pang, Wentao; Zhang, Ziyi; Zhao, Jialong; Wang, Xin; Liu, Ye; Wang, Xun; Feng, Zhihui; Zhang, Yong; Sun, Wenyan; Liu, Jiankang

2016-06-01

Obesity is reported to be associated with immune dysfunction and a state of low-grade, chronic inflammation. Either pomegranate extract (PomE) or exercise (Ex) has been shown to have antiobesity, anti-inflammatory and antioxidant effects. Nevertheless, no study has addressed the additive benefits of PomE and Ex on the restoration of obesity-induced immune defects. The present work aims to study the effect of PomE and Ex as a combined intervention on immune function and the underlying mechanism involved in inflammation and oxidative stress in rats with high-fat-diet (HFD)-induced obesity. Our results demonstrate that the combination of PomE and Ex showed additive benefits on inhibition of HFD-induced body weight increase and improvement of HFD-induced immune dysfunction, including (a) attenuating the abnormality of histomorphology of the spleen, (b) increasing the ratio of the CD4+:CD8+ T cell subpopulations in splenocytes and peripheral blood mononuclear cells (PBMC), (c) inhibition of apoptosis in splenocytes and PBMC, (d) normalizing peritoneal macrophage phenotypes and (e) restoring immunomodulating factors in serum. We also find that immune dysfunction in HFD-fed rats was associated with increased inflammatory cytokine secretion and oxidative stress biomarkers, and that the combination of PomE and Ex effectively inhibited the inflammatory response and decreased oxidative damage. The effect of PomE and Ex as a combined intervention is greater than the effect of either PomE or Ex alone, showing that PomE and Ex may be additively effective in improving immune function in HFD-fed rats by inhibiting inflammation and decreasing oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Implications of immune dysfunction on endometriosis associated infertility

PubMed Central

Miller, Jessica E.; Ahn, Soo Hyun; Monsanto, Stephany P.; Khalaj, Kasra; Koti, Madhuri; Tayade, Chandrakant

2017-01-01

Endometriosis is a complex, inflammatory disease that affects 6-10% of reproductive-aged women. Almost half of the women with endometriosis experience infertility. Despite the excessive prevalence, the pathogenesis of endometriosis and its associated infertility is unknown and a cure is not available. While many theories have been suggested to link endometriosis and infertility, a consensus among investigators has not emerged. In this extensive review of the literature as well as research from our laboratory, we provide potential insights into the role of immune dysfunction in endometriosis associated infertility. We discuss the implication of the peritoneal inflammatory microenvironment on various factors that contribute to infertility such as hormonal imbalance, oxidative stress and how these could further lead to poor oocyte, sperm and embryo quality, impaired receptivity of the endometrium and implantation failure. PMID:27740937

Implications of immune dysfunction on endometriosis associated infertility.

PubMed

Miller, Jessica E; Ahn, Soo Hyun; Monsanto, Stephany P; Khalaj, Kasra; Koti, Madhuri; Tayade, Chandrakant

2017-01-24

Endometriosis is a complex, inflammatory disease that affects 6-10% of reproductive-aged women. Almost half of the women with endometriosis experience infertility. Despite the excessive prevalence, the pathogenesis of endometriosis and its associated infertility is unknown and a cure is not available. While many theories have been suggested to link endometriosis and infertility, a consensus among investigators has not emerged. In this extensive review of the literature as well as research from our laboratory, we provide potential insights into the role of immune dysfunction in endometriosis associated infertility. We discuss the implication of the peritoneal inflammatory microenvironment on various factors that contribute to infertility such as hormonal imbalance, oxidative stress and how these could further lead to poor oocyte, sperm and embryo quality, impaired receptivity of the endometrium and implantation failure.

Elevated stress hormone levels relate to Epstein-Barr virus reactivation in astronauts

NASA Technical Reports Server (NTRS)

Stowe, R. P.; Pierson, D. L.; Barrett, A. D.

2001-01-01

OBJECTIVE: The objective of this study was to determine the effects of stress and spaceflight on levels of neuroendocrine hormones and Epstein-Barr virus (EBV)-specific antibodies in astronauts. METHODS: Antiviral antibody titers and stress hormones were measured in plasma samples collected from 28 astronauts at their annual medical exam (baseline), 10 days before launch (L-10), landing day (R+0), and 3 days after landing (R+3). Urinary stress hormones were also measured at L-10 and R+0. RESULTS: Significant increases (p <.01) in EBV virus capsid antigen antibodies were found at all three time points (L-10, R+0, and R+3) as compared with baseline samples. Anti-EBV nuclear antigen antibodies were significantly decreased at L-10 (p <.05) and continued to decrease after spaceflight (R+0 and R+3, p <.01). No changes were found in antibodies to the nonlatent measles virus. The 11 astronauts who showed evidence of EBV reactivation had significant increases in urinary epinephrine and norepinephrine as compared with astronauts without EBV reactivation. CONCLUSION: These findings indicate that physical and psychological stresses associated with spaceflight resulted in decreased virus-specific T-cell immunity and reactivation of EBV.

Gravity changes during animal development affect IgM heavy-chain transcription and probably lymphopoiesis.

PubMed

Huin-Schohn, Cécile; Guéguinou, Nathan; Schenten, Véronique; Bascove, Matthieu; Koch, Guillemette Gauquelin; Baatout, Sarah; Tschirhart, Eric; Frippiat, Jean-Pol

2013-01-01

Our previous research demonstrated that spaceflight conditions affect antibody production in response to an antigenic stimulation in adult amphibians. Here, we investigated whether antibody synthesis is affected when animal development occurs onboard a space station. To answer this question, embryos of the Iberian ribbed newt, Pleurodeles waltl, were sent to the International Space Station (ISS) before the initiation of immunoglobulin heavy-chain expression. Thus, antibody synthesis began in space. On landing, we determined the effects of spaceflight on P. waltl development and IgM heavy-chain transcription. Results were compared with those obtained using embryos that developed on Earth. We find that IgM heavy-chain transcription is doubled at landing and that spaceflight does not affect P. waltl development and does not induce inflammation. We also recreated the environmental modifications encountered by the embryos during their development onboard the ISS. This strategy allowed us to demonstrate that gravity change is the factor responsible for antibody heavy-chain transcription modifications that are associated with NF-κB mRNA level variations. Taken together, and given that the larvae were not immunized, these data suggest a modification of lymphopoiesis when gravity changes occur during ontogeny.

Chronic retinal necrosis: cytomegalovirus necrotizing retinitis associated with panretinal vasculopathy in non-HIV patients.

PubMed

Schneider, Eric W; Elner, Susan G; van Kuijk, Frederik J; Goldberg, Naomi; Lieberman, Ronni M; Eliott, Dean; Johnson, Mark W

2013-10-01

To characterize a unique cytomegalovirus (CMV)-associated retinopathy in patients with limited immune dysfunction. Retrospective observational case series. CMV was confirmed as the pathogenic agent via polymerase chain reaction analysis of aqueous or vitreous humor samples or via immunohistochemical analysis of retinal biopsy specimens. Five non-HIV patients with granular necrotizing retinitis, vitritis, and severe occlusive vasculopathy were identified. Patient histories all suggested a basis for limited immune dysfunction including advanced age (n = 4), diabetes mellitus (n = 4), and noncytotoxic immunotherapy (n = 3). Diagnosis of CMV retinitis was delayed in all cases and patients received either no antiviral therapy (n = 2) or incorrect antiviral therapy (n = 3) for presumed herpes simplex/varicella zoster-related acute retinal necrosis. Retinitis subsequently regressed in all cases with introduction of systemic ganciclovir/valganciclovir (n = 5) and/or intravitreal foscarnet (n = 2). Four of five patients developed neovascularization because of extensive retinal ischemia. The clinical expression of CMV-associated retinopathy is strongly related to immune status. In patients with limited immune dysfunction, a mixed clinical picture of intraocular inflammation with panretinal occlusive vasculopathy, more characteristic of acute retinal necrosis, and peripheral slowly progressive granular retinitis, more characteristic of classic CMV retinitis, is observed. Recognition of this atypical clinical presentation, which the authors term chronic retinal necrosis, should prompt molecular testing for CMV to determine the appropriate antiviral therapy. Consideration should also be given to prophylactic panretinal photocoagulation in such eyes, given the high risk of neovascular complications.

Development of a Deltoid Shoulder Muscle Model for Rhesus Monkey Spaceflight Studies

NASA Technical Reports Server (NTRS)

Riley, Danny A.; Macias, Melissa Y.; Anders, Scott; Slocum, Glenn R.

1995-01-01

The acromiodeltoid shoulder muscle was demonstrated to be a suitable model for spaceflight studies. The muscle contains a mixture of fast and slow fibers, permitting analysis of muscle fiber type specific changes. Two biopsy sites per muscle were identified that provided samples not degraded by the biopsy procedure. Both sites contained sufficient numbers fibers for determining changes in fiber type percentages and size. There was adequate bilateral symmetry regarding fiber type composition in the left and right muscles such that a total of four times points can be compared. The ESOP cage did not cause atrophy of deltoid muscle fibers; this means that microgravity-induced atrophy should be detectable. As expected, muscle excision stimulated muscle IgM and IgG muscle autoantibody production. Nonrestrained control animals suppressed this response whereas restrained monkeys showed an abnormally pronounced response indicative a compromised immune system. The presence of ESOP cage-induced changes in the immune response may mask spaceflight-induced effects. The ESOP cage modified the dominant hand operation of the PTS. These results demonstrate the importance of high fidelity ground based controls.

A review of research trends in physiological abnormalities in autism spectrum disorders: immune dysregulation, inflammation, oxidative stress, mitochondrial dysfunction and environmental toxicant exposures

PubMed Central

Rossignol, D A; Frye, R E

2012-01-01

Recent studies have implicated physiological and metabolic abnormalities in autism spectrum disorders (ASD) and other psychiatric disorders, particularly immune dysregulation or inflammation, oxidative stress, mitochondrial dysfunction and environmental toxicant exposures (‘four major areas'). The aim of this study was to determine trends in the literature on these topics with respect to ASD. A comprehensive literature search from 1971 to 2010 was performed in these four major areas in ASD with three objectives. First, publications were divided by several criteria, including whether or not they implicated an association between the physiological abnormality and ASD. A large percentage of publications implicated an association between ASD and immune dysregulation/inflammation (416 out of 437 publications, 95%), oxidative stress (all 115), mitochondrial dysfunction (145 of 153, 95%) and toxicant exposures (170 of 190, 89%). Second, the strength of evidence for publications in each area was computed using a validated scale. The strongest evidence was for immune dysregulation/inflammation and oxidative stress, followed by toxicant exposures and mitochondrial dysfunction. In all areas, at least 45% of the publications were rated as providing strong evidence for an association between the physiological abnormalities and ASD. Third, the time trends in the four major areas were compared with trends in neuroimaging, neuropathology, theory of mind and genetics (‘four comparison areas'). The number of publications per 5-year block in all eight areas was calculated in order to identify significant changes in trends. Prior to 1986, only 12 publications were identified in the four major areas and 51 in the four comparison areas (42 for genetics). For each 5-year period, the total number of publications in the eight combined areas increased progressively. Most publications (552 of 895, 62%) in the four major areas were published in the last 5 years (2006–2010). Evaluation of trends between the four major areas and the four comparison areas demonstrated that the largest relative growth was in immune dysregulation/inflammation, oxidative stress, toxicant exposures, genetics and neuroimaging. Research on mitochondrial dysfunction started growing in the last 5 years. Theory of mind and neuropathology research has declined in recent years. Although most publications implicated an association between the four major areas and ASD, publication bias may have led to an overestimation of this association. Further research into these physiological areas may provide insight into general or subset-specific processes that could contribute to the development of ASD and other psychiatric disorders. PMID:22143005

Necrotizing herpetic retinopathies. A spectrum of herpes virus-induced diseases determined by the immune state of the host.

PubMed

Guex-Crosier, Y; Rochat, C; Herbort, C P

1997-12-01

Necrotizing herpetic retinopathies (NHR), a new spectrum of diseases induced by viruses of the herpes family (herpes simplex virus, varicella-zoster virus and cytomegalovirus), includes acute retinal necrosis (ARN) occurring in apparently immunocompetent patients and progressive outer retinal necrosis (PORN) described in severely immuno-compromised patients. Signs of impaired cellular immunity were seen in 16% of ARN patients in a review of 216 reported cases, indicating that immune dysfunction is not only at the origin of PORN but might also be at the origin of ARN. The aim of this study was to correlate clinical findings in NHR patients with their immunologic parameters. Charts from patients with the diagnosis of ARN or PORN seen from 1990 to 1995 were reviewed. Clinical characteristics and disease patterns were correlated with immunological parameters taking into account CD4 lymphocyte rate in AIDS patients and blood-lymphocyte subpopulation determination by flow cytometry, cutaneous delayed type hypersensitivity testing and lymphocytic proliferation rate to seven antigens in HIV-negative patients. During the period considered, 11 patients and 7 patients fulfilled the criteria of ARN and PORN respectively. Immune dysfunctions were identified in most patients. Mild type of ARN and classical ARN were associated with discrete immune dysfunctions, ARN with features of PORN was seen in more immunodepressed patients and classical PORN was always seen in severely immunodepressed HIV patients. Our findings suggest that NHR is a continuous spectrum of diseases induced by herpes viruses, whose clinical expression depends on the immune state of the host going from mild or classical ARN at one end in patients with non-detectable or slight immune dysfunction to PORN in severely immunodepressed patients at the other end and with intermediary forms between these extremes.

Effects of Space Missions on the Human Immune System: A Meta-Analysis

NASA Technical Reports Server (NTRS)

Greenleaf, J. E.; Barger, L. K.; Baldini, F.; Huff, D.

1995-01-01

Future spaceflight will require travelers to spend ever-increasing periods of time in microgravity. Optimal functioning of the immune system is of paramount importance for the health and performance of these travelers. A meta-analysis statistical procedure was used to analyze immune system data from crew members in United States and Soviet space missions from 8.5 to 140 days duration between 1968 and 1985. Ten immunological parameters (immunoglobulins A, G, M, D, white blood cell (WBC) count, number of lymphocytes, percent total lymphocytes, percent B lymphocytes, percent T lymphocytes, and lymphocyte reactivity to mitogen) were investigated using multifactorial, repeated measure analysis of variance. With the preflight level set at 100, WBC count increased to 154 +/- 14% (mean +/- SE; p less than or equal to 0.05) immediately after flight; there was a decrease in lymphocyte count (83 +/- 4%; p less than or equal to 0.05) and percent of total lymphocytes (69 +/- 1%; p less than or equal to 0.05) immediately after flight, with reduction in RNA synthesis to phytohemagglutinin (PHA) to 51 +/- 21% (p less than or equal to 0.05) and DNA synthesis to PHA to 61 +/- 8% (p less than or equal to 0.05) at the first postflight measurement. Thus, some cellular immunological functions are decreased significantly following spaceflight. More data are needed on astronauts' age, aerobic power output, and parameters of their exercise training program to determine if these immune system responses are due solely to microgravity exposure or perhaps to some other aspect of spaceflight.

Altered tumor cell growth and tumorigenicity in models of microgravity

NASA Astrophysics Data System (ADS)

Yamauchi, K.; Taga, M.; Furian, L.; Odle, J.; Sundaresan, A.; Pellis, N.; Andrassy, R.; Kulkarni, A.

Spaceflight environment and microgravity (MG) causes immune dysfunction and is a major health risk to humans, especially during long-term space missions. The effects of microgravity environment on tumor growth and carcinogenesis are yet unknown. Hence, we investigated the effects of simulated MG (SMG) on tumor growth and tumorigenicity using in vivo and in vitro models. B16 melanoma cells were cultured in static flask (FL) and rotating wall vessel bioreactors (BIO) to measure growth and properties, melanin production and apoptosis. BIO cultures had 50% decreased growth (p<0.01), increased doubling time and a 150% increase in melanin production (p<0.05). Flow cytometric analysis showed increased apoptosis in BIO. When BIO cultured melanoma cells were inoculated sc in mice there was a significant increase in tumorigenicity as compared to FL cells. Thus SMG may have supported &selected highly tumorigenic cells and it is pos sible that in addition to decreased immune function MG may alter tumor cell characteristics and invasiveness. Thus it is important to study effects of microgravity environment and its stressors using experimental tumors and SMG to understand and evaluate carcinogenic responses to true microgravity. Further studies on carcinogenic events and their mechanisms will allow us develop and formulate countermeasures and protect space travelers. Additional results will be presented. (Supported by NASA NCC8-168 grant, ADK)

Immunotherapy for glioblastoma: playing chess, not checkers.

PubMed

Jackson, Christopher M; Lim, Michael

2018-04-24

Patients with glioblastoma (GBM) exhibit a complex state of immune dysfunction involving multiple mechanisms of local, regional, and systemic immune suppression and tolerance. These pathways are now being identified and their relative contributions explored. Delineating how these pathways are interrelated is paramount to effectively implementing immunotherapy for GBM. Copyright ©2018, American Association for Cancer Research.

Oral Human Immunoglobulin for Children with Autism and Gastrointestinal Dysfunction: A Prospective, Open-Label Study

ERIC Educational Resources Information Center

Schneider, Cindy K.; Melmed, Raun D.; Barstow, Leon E.; Enriquez, F. Javier; Ranger-Moore, James; Ostrem, James A.

2006-01-01

Immunoglobulin secretion onto mucosal surfaces is a major component of the mucosal immune system. We hypothesized that chronic gastrointestinal (GI) disturbances associated with autistic disorder (AD) may be due to an underlying deficiency in mucosal immunity, and that orally administered immunoglobulin would be effective in alleviating chronic GI…

Spaceflight Activates Lipotoxic Pathways in Mouse Liver

PubMed Central

Jonscher, Karen R.; Alfonso-Garcia, Alba; Suhalim, Jeffrey L.; Orlicky, David J.; Potma, Eric O.; Ferguson, Virginia L.; Bouxsein, Mary L.; Bateman, Ted A.; Stodieck, Louis S.; Levi, Moshe; Friedman, Jacob E.; Gridley, Daila S.; Pecaut, Michael J.

2016-01-01

Spaceflight affects numerous organ systems in the body, leading to metabolic dysfunction that may have long-term consequences. Microgravity-induced alterations in liver metabolism, particularly with respect to lipids, remain largely unexplored. Here we utilize a novel systems biology approach, combining metabolomics and transcriptomics with advanced Raman microscopy, to investigate altered hepatic lipid metabolism in mice following short duration spaceflight. Mice flown aboard Space Transportation System -135, the last Shuttle mission, lose weight but redistribute lipids, particularly to the liver. Intriguingly, spaceflight mice lose retinol from lipid droplets. Both mRNA and metabolite changes suggest the retinol loss is linked to activation of PPARα-mediated pathways and potentially to hepatic stellate cell activation, both of which may be coincident with increased bile acids and early signs of liver injury. Although the 13-day flight duration is too short for frank fibrosis to develop, the retinol loss plus changes in markers of extracellular matrix remodeling raise the concern that longer duration exposure to the space environment may result in progressive liver damage, increasing the risk for nonalcoholic fatty liver disease. PMID:27097220

Tolerance of centrifuge-simulated suborbital spaceflight in subjects with implanted insulin pumps.

PubMed

Levin, Dana R; Blue, Rebecca S; Castleberry, Tarah L; Vanderploeg, James M

2015-04-01

With commercial spaceflight comes the possibility of spaceflight participants (SFPs) with significant medical conditions. Those with previously untested medical conditions, such as diabetes mellitus (DM) and the use of indwelling medical devices, represent a unique challenge. It is unclear how SFPs with such devices will react to the stresses of spaceflight. This case report describes two subjects with Type I DM using insulin pumps who underwent simulated dynamic phases of spaceflight via centrifuge G force exposure. Two Type I diabetic subjects with indwelling Humalog insulin pumps, a 23-yr-old man averaging 50 u of Humalog daily and a 27-yr-old man averaging 60 u of Humalog daily, underwent seven centrifuge runs over 48 h. Day 1 consisted of two +Gz runs (peak = +3.5 Gz, run 2) and two +Gx runs (peak = +6.0 Gx, run 4). Day 2 consisted of three runs approximating suborbital spaceflight profiles (combined +Gx and +Gz). Data collected included blood pressure, electrocardiogram, pulse oximetry, neurovestibular evaluation, and questionnaires regarding motion sickness, disorientation, greyout, and other symptoms. Neither subject experienced adverse clinical responses to the centrifuge exposure. Both maintained blood glucose levels between 110-206 mg · dl(-1). Potential risks to SFPs with insulin pump dependent DM include hypo/hyperglycemia, pump damage, neurovestibular dysfunction, skin breakdown, and abnormal stress responses. A search of prior literature did not reveal any previous studies of individuals with DM on insulin pumps exposed to prolonged accelerations. These cases suggest that individuals with conditions dependent on continuous medication delivery might tolerate the accelerations anticipated for commercial spaceflight.

Immune Modulation in Normal Human Peripheral Blood Mononuclear Cells (PBMCs) (Lymphocytes) in Response to Benzofuran-2-Carboxylic Acid Derivative KMEG during Spaceflight

NASA Astrophysics Data System (ADS)

Okoro, Elvis; Mann, Vivek; Ellis, Ivory; Mansoor, Elvedina; Olamigoke, Loretta; Marriott, Karla Sue; Denkins, Pamela; Williams, Willie; Sundaresan, Alamelu

2017-08-01

Microgravity and radiation exposure during space flight have been widely reported to induce the suppression of normal immune system function, and increase the risk of cancer development in humans. These findings pose a serious risk to manned space missions. Interestingly, recent studies have shown that benzofuran-2-carboxylic acid derivatives can inhibit the progression of some of these devastating effects on earth and in modeled microgravity. However, these studies had not assessed the impacts of benzofuran-2- carboxylic acid and its derivatives on global gene expression under spaceflight conditions. In this study, the ability of a specific benzofuran-2-carboxylic acid derivative (KMEG) to confer protection from radiation and restore normal immune function was investigated following exposure to space flight conditions on the ISS. Normal human peripheral blood mononuclear cells (lymphocytes) treated with 10 µ g/ml of KMEG together with untreated control samples were flown on Nanoracks hardware on Spacex-3 flight. The Samples were returned one month later and gene expression was analyzed. A 1g-ground control experiment was performed in parallel at the Kennedy spaceflight center. The first overall subtractive unrestricted analysis revealed 78 genes, which were differentially expressed in space flight KMEG, untreated lymphocytes as compared to the corresponding ground controls. However, in KMEG-treated space flight lymphocytes, there was an increased expression of a group of genes that mediate increased transcription, translation and innate immune system mediating functions of lymphocytes as compared to KMEG-untreated samples. Analysis of genes related to T cell proliferation in spaceflight KMEG-treated lymphocytes compared to 1g-ground KMEG- treated lymphocytes revealed six T cell proliferation and signaling genes to be significantly upregulated (p < 0.001) and five related genes were found to be significantly down-regulated. These genes play a significant role in promoting the proliferation of T-lymphocytes, the regulation of membrane trafficking, promote early response, mediating C-myc related proliferation, promote antiapoptotic activity and protects mitochondria from the accumulation of oxidatively damaged membrane proteins. Overall, our analysis indicates that KMEG promotes T- cell proliferation and has an anti-inflammatory effect, thereby increasing immunity and possible protection from chronic inflammation setting which is optimally required during long term space flights.

History of suborbital spaceflight: medical and performance issues.

PubMed

Campbell, Mark R; Garbino, Alejandro

2011-04-01

The development of manned sub-orbital commercial space vehicles is rapidly occurring and flight testing followed by operational flights will soon begin. The experience of manned suborbital spaceflight at the designated altitude (100 km/62.14 mi) is very limited--two Mercury-Redstone flights, two X-15 flights, one inadvertent Soyuz launch abort, and three recent SpaceShipOne flights, with only 15 min of critical flight time each. All indications were that the sequence of acceleration-weightlessness-deceleration was well tolerated with minimal neurovestibular dysfunction. However, there are some indications that distraction and spatial disorientation did occur. Vertigo on transition from the boost phase to weightlessness was reported on most high-altitude X-15 flights. +Gz tolerance to re-entry deceleration forces (as high as 6 + Gz) after 4 min of weightlessness is still unknown. Only further suborbital spaceflight experience will clarify if pilot performance will be affected.

A Preliminary Exercise Study of Japanese Version of High-intensity Interval Aerobic Training (J-HIAT)

NASA Astrophysics Data System (ADS)

Matsuo, Tomoaki; Seino, Satoshi; Ohkawara, Kazunori; Tanaka, Kiyoji; Yamada, Shin; Ohshima, Hiroshi; Mukai, Chiaki

In a microgravity environment, the volume load on the left ventricle is reduced and the cardiac function deteriorates.Consequently, maximal oxygen consumption (VO2max) decreases during spaceflight. Reduced cardiac function can lead to serious health problems such as cardiac atrophy, diastolic dysfunction, and orthostatic hypotension. An exercise using a bicycle ergometer during spaceflight may help to increase the volume load on the left ventricle. On the other hand, many astronauts also experience weight loss during spaceflight because energy imbalances can occur. Some researchers indicate that excessive exercise may promote the energy deficit and have a negative impact on long-term spaceflight. Therefore, we have been devising an original bicyle erogometer protocol better suited to astronauts experiencing long-term spaceflight.One of our candidate protocols is the 3 × 3 protocol named J-HIAT, i.e., three times 3-min intervals with a 2-min active recovery period between intervals. In response to our preliminary experiments, we concluded that J-HIAT would be a potential protocol to control the increase of energy consumption and to have a significant impact on VO2max and the cardiac function. To further verify this method, we are working on full-scale experiments. In future, we will show the results of these experiments.

The Role of the Immune System in Autism Spectrum Disorder

PubMed Central

Meltzer, Amory; Van de Water, Judy

2017-01-01

Autism is a neurodevelopmental disorder characterized by deficits in communication and social skills as well as repetitive and stereotypical behaviors. While much effort has focused on the identification of genes associated with autism, research emerging within the past two decades suggests that immune dysfunction is a viable risk factor contributing to the neurodevelopmental deficits observed in autism spectrum disorders (ASD). Further, it is the heterogeneity within this disorder that has brought to light much of the current thinking regarding the subphenotypes within ASD and how the immune system is associated with these distinctions. This review will focus on the two main axes of immune involvement in ASD, namely dysfunction in the prenatal and postnatal periods. During gestation, prenatal insults including maternal infection and subsequent immunological activation may increase the risk of autism in the child. Similarly, the presence of maternally derived anti-brain autoantibodies found in ~20% of mothers whose children are at risk for developing autism has defined an additional subphenotype of ASD. The postnatal environment, on the other hand, is characterized by related but distinct profiles of immune dysregulation, inflammation, and endogenous autoantibodies that all persist within the affected individual. Further definition of the role of immune dysregulation in ASD thus necessitates a deeper understanding of the interaction between both maternal and child immune systems, and the role they have in diagnosis and treatment. PMID:27534269

Omics Research on the International Space Station

NASA Technical Reports Server (NTRS)

Love, John

2015-01-01

The International Space Station (ISS) is an orbiting laboratory whose goals include advancing science and technology research. Completion of ISS assembly ushered a new era focused on utilization, encompassing multiple disciplines such as Biology and Biotechnology, Physical Sciences, Technology Development and Demonstration, Human Research, Earth and Space Sciences, and Educational Activities. The research complement planned for upcoming ISS Expeditions 45&46 includes several investigations in the new field of omics, which aims to collectively characterize sets of biomolecules (e.g., genomic, epigenomic, transcriptomic, proteomic, and metabolomic products) that translate into organismic structure and function. For example, Multi-Omics is a JAXA investigation that analyzes human microbial metabolic cross-talk in the space ecosystem by evaluating data from immune dysregulation biomarkers, metabolic profiles, and microbiota composition. The NASA OsteoOmics investigation studies gravitational regulation of osteoblast genomics and metabolism. Tissue Regeneration uses pan-omics approaches with cells cultured in bioreactors to characterize factors involved in mammalian bone tissue regeneration in microgravity. Rodent Research-3 includes an experiment that implements pan-omics to evaluate therapeutically significant molecular circuits, markers, and biomaterials associated with microgravity wound healing and tissue regeneration in bone defective rodents. The JAXA Mouse Epigenetics investigation examines molecular alterations in organ specific gene expression patterns and epigenetic modifications, and analyzes murine germ cell development during long term spaceflight. Lastly, Twins Study ("Differential effects of homozygous twin astronauts associated with differences in exposure to spaceflight factors"), NASA's first foray into human omics research, applies integrated analyses to assess biomolecular responses to physical, physiological, and environmental stressors associated with spaceflight.

Characterization and implications of thyroid dysfunction induced by immune checkpoint inhibitors in real-life clinical practice: a long-term prospective study from a referral institution.

PubMed

Guaraldi, F; La Selva, R; Samà, M T; D'Angelo, V; Gori, D; Fava, P; Fierro, M T; Savoia, P; Arvat, E

2018-05-01

Autoimmune diseases are typically associated with immune checkpoints blockade. This study aims at assessing, in real-life clinical practice, the prevalence and impact of thyroid disorders induced by immune checkpoint inhibitors. 52 patients (30 F; age 61 ± 13 years) with advanced melanoma treated with ipilimumab (3 mg/kg i.v./3 weeks; 4 doses) were included. For disease progression, 29 (16 F) of them received nivolumab (3 mg/kg i.v./2 weeks) or pembrolizumab (2 mg/kg i.v./3 weeks). Thyroid function and autoimmunity were assessed before, after 6 weeks, at the end of ipilimumab, as well as before and every 3 months during nivolumab/pembrolizumab treatment. During ipilimumab, 7 (4 F) patients developed thyroid dysfunction (4 thyroiditis, 1 associated with hypothyroidism; 2 thyrotoxicosis in a previously euthyroid multinodular goiter; 1 hypothyroidism worsened). During PD1 inhibitors, 7 patients (3 F) developed hypothyroidism with severe manifestations in 6 of them; 3 patients suffered from euthyroid autoimmune thyroiditis from baseline, one after ipilimumab; 2 patients developed after transient thyrotoxicosis. Mean follow-up after anti-CTLA4 inhibitors treatment was 36 ± 28 months. Thyroid disorders occurred 45.1 ± 20.8 and 151 ± 67 days after the initiation of CTLA4 and PD1 inhibitors, respectively. Autoimmune disorders and BRAF mutation were associated with a better clinical response to CTLA4 followed by PD1 treatment. Immune checkpoint blockade is burdened by a high incidence of autoimmune thyroid dysfunction, which is often severe. Therefore, early and careful monitoring and, eventually, treatment are crucial to prevent the negative impact of thyroid dysfunction on the clinical outcome.

Dendritic cells modulate lung response to Pseudomonas aeruginosa in a murine model of sepsis-induced immune dysfunction.

PubMed

Pène, Frédéric; Zuber, Benjamin; Courtine, Emilie; Rousseau, Christophe; Ouaaz, Fatah; Toubiana, Julie; Tazi, Asmaa; Mira, Jean-Paul; Chiche, Jean-Daniel

2008-12-15

Host infection by pathogens triggers an innate immune response leading to a systemic inflammatory response, often followed by an immune dysfunction which can favor the emergence of secondary infections. Dendritic cells (DCs) link innate and adaptive immunity and may be centrally involved in the regulation of sepsis-induced immune dysfunction. We assessed the contribution of DCs to lung defense in a murine model of sublethal polymicrobial sepsis (cecal ligature and puncture, CLP). In this model, bone marrow-derived DCs (BMDCs) retained an immature phenotype, associated with decreased capacity of IL-12p70 release and impaired priming of T cell lymphocytes. Eight days after CLP surgery, we induced a secondary pulmonary infection through intratracheal instillation of 5 x 10(6) CFUs of Pseudomonas aeruginosa. Whereas all sham-operated mice survived, 80% of post-CLP mice died after secondary pneumonia. Post-CLP mice exhibited marked lung damage with early recruitment of neutrophils, cytokine imbalance with decreased IL-12p70 production, and increased IL-10 release, but no defective bacterial lung clearance, while systemic bacterial dissemination was almost constant. Concomitant intrapulmonary administration of exogenous BMDCs into post-CLP mice challenged with P. aeruginosa dramatically improved survival. BMDCs did not improve bacterial lung clearance, but delayed neutrophil recruitment, strongly attenuated the early peak of TNF-alpha and restored an adequate Il-12p70/IL-10 balance in post-CLP mice. Thus, adoptive transfer of BMDCs reversed sepsis-induced immune dysfunction in a relevant model of secondary P. aeruginosa pneumonia. Unexpectedly, the mechanism of action of BMDCs did not involve enhanced antibacterial activity, but occurred by dampening the pulmonary inflammatory response.

Immune-related genetic enrichment in frontotemporal dementia: An analysis of genome-wide association studies.

PubMed

Broce, Iris; Karch, Celeste M; Wen, Natalie; Fan, Chun C; Wang, Yunpeng; Tan, Chin Hong; Kouri, Naomi; Ross, Owen A; Höglinger, Günter U; Muller, Ulrich; Hardy, John; Momeni, Parastoo; Hess, Christopher P; Dillon, William P; Miller, Zachary A; Bonham, Luke W; Rabinovici, Gil D; Rosen, Howard J; Schellenberg, Gerard D; Franke, Andre; Karlsen, Tom H; Veldink, Jan H; Ferrari, Raffaele; Yokoyama, Jennifer S; Miller, Bruce L; Andreassen, Ole A; Dale, Anders M; Desikan, Rahul S; Sugrue, Leo P

2018-01-01

Converging evidence suggests that immune-mediated dysfunction plays an important role in the pathogenesis of frontotemporal dementia (FTD). Although genetic studies have shown that immune-associated loci are associated with increased FTD risk, a systematic investigation of genetic overlap between immune-mediated diseases and the spectrum of FTD-related disorders has not been performed. Using large genome-wide association studies (GWASs) (total n = 192,886 cases and controls) and recently developed tools to quantify genetic overlap/pleiotropy, we systematically identified single nucleotide polymorphisms (SNPs) jointly associated with FTD-related disorders-namely, FTD, corticobasal degeneration (CBD), progressive supranuclear palsy (PSP), and amyotrophic lateral sclerosis (ALS)-and 1 or more immune-mediated diseases including Crohn disease, ulcerative colitis (UC), rheumatoid arthritis (RA), type 1 diabetes (T1D), celiac disease (CeD), and psoriasis. We found up to 270-fold genetic enrichment between FTD and RA, up to 160-fold genetic enrichment between FTD and UC, up to 180-fold genetic enrichment between FTD and T1D, and up to 175-fold genetic enrichment between FTD and CeD. In contrast, for CBD and PSP, only 1 of the 6 immune-mediated diseases produced genetic enrichment comparable to that seen for FTD, with up to 150-fold genetic enrichment between CBD and CeD and up to 180-fold enrichment between PSP and RA. Further, we found minimal enrichment between ALS and the immune-mediated diseases tested, with the highest levels of enrichment between ALS and RA (up to 20-fold). For FTD, at a conjunction false discovery rate < 0.05 and after excluding SNPs in linkage disequilibrium, we found that 8 of the 15 identified loci mapped to the human leukocyte antigen (HLA) region on Chromosome (Chr) 6. We also found novel candidate FTD susceptibility loci within LRRK2 (leucine rich repeat kinase 2), TBKBP1 (TBK1 binding protein 1), and PGBD5 (piggyBac transposable element derived 5). Functionally, we found that the expression of FTD-immune pleiotropic genes (particularly within the HLA region) is altered in postmortem brain tissue from patients with FTD and is enriched in microglia/macrophages compared to other central nervous system cell types. The main study limitation is that the results represent only clinically diagnosed individuals. Also, given the complex interconnectedness of the HLA region, we were not able to define the specific gene or genes on Chr 6 responsible for our pleiotropic signal. We show immune-mediated genetic enrichment specifically in FTD, particularly within the HLA region. Our genetic results suggest that for a subset of patients, immune dysfunction may contribute to FTD risk. These findings have potential implications for clinical trials targeting immune dysfunction in patients with FTD.

Physiological Aging: Links Among Adipose Tissue Dysfunction, Diabetes, and Frailty

PubMed Central

Stout, Michael B.; Justice, Jamie N.; Nicklas, Barbara J.; Kirkland, James L.

2016-01-01

Advancing age is associated with progressive declines in physiological function that lead to overt chronic disease, frailty, and eventual mortality. Importantly, age-related physiological changes occur in cellularity, insulin-responsiveness, secretory profiles, and inflammatory status of adipose tissue, leading to adipose tissue dysfunction. Although the mechanisms underlying adipose tissue dysfunction are multifactorial, the consequences result in secretion of proinflammatory cytokines and chemokines, immune cell infiltration, an accumulation of senescent cells, and an increase in senescence-associated secretory phenotype (SASP). These processes synergistically promote chronic sterile inflammation, insulin resistance, and lipid redistribution away from subcutaneous adipose tissue. Without intervention, these effects contribute to age-related systemic metabolic dysfunction, physical limitations, and frailty. Thus adipose tissue dysfunction may be a fundamental contributor to the elevated risk of chronic disease, disability, and adverse health outcomes with advancing age. PMID:27927801

Pathogenic Correlates of Simian Immunodeficiency Virus-Associated B Cell Dysfunction.

PubMed

Brocca-Cofano, Egidio; Kuhrt, David; Siewe, Basile; Xu, Cuiling; Haret-Richter, George S; Craigo, Jodi; Labranche, Celia; Montefiori, David C; Landay, Alan; Apetrei, Cristian; Pandrea, Ivona

2017-12-01

We compared and contrasted pathogenic (in pig-tailed macaques [PTMs]) and nonpathogenic (in African green monkeys [AGMs]) SIVsab infections to assess the significance of the B cell dysfunction observed in simian (SIV) and human immunodeficiency virus (HIV) infections. We report that the loss of B cells is specifically associated with the pathogenic SIV infection, while in the natural hosts, in which SIV is nonpathogenic, B cells rapidly increase in both lymph nodes (LNs) and intestine. SIV-associated B cell dysfunction associated with the pathogenic SIV infection is characterized by loss of naive B cells, loss of resting memory B cells due to their redistribution to the gut, increases of the activated B cells and circulating tissue-like memory B cells, and expansion of the B regulatory cells (Bregs). While circulating B cells are virtually restored to preinfection levels during the chronic pathogenic SIV infection, restoration is mainly due to an expansion of the "exhausted," virus-specific B cells, i.e., activated memory cells and tissue-like memory B cells. Despite of the B cell dysfunction, SIV-specific antibody (Ab) production was higher in the PTMs than in AGMs, with the caveat that rapid disease progression in PTMs was strongly associated with lack of anti-SIV Ab. Neutralization titers and the avidity and maturation of immune responses did not differ between pathogenic and nonpathogenic infections, with the exception of the conformational epitope recognition, which evolved from low to high conformations in the natural host. The patterns of humoral immune responses in the natural host are therefore more similar to those observed in HIV-infected subjects, suggesting that natural hosts may be more appropriate for modeling the immunization strategies aimed at preventing HIV disease progression. The numerous differences between the pathogenic and nonpathogenic infections with regard to dynamics of the memory B cell subsets point to their role in the pathogenesis of HIV/SIV infections and suggest that monitoring B cells may be a reliable approach for assessing disease progression. IMPORTANCE We report here that the HIV/SIV-associated B cell dysfunction (defined by loss of total and memory B cells, increased B regulatory cell [Breg] counts, and B cell activation and apoptosis) is specifically associated with pathogenic SIV infection and absent during the course of nonpathogenic SIV infection in natural nonhuman primate hosts. Alterations of the B cell population are not correlated with production of neutralizing antibodies, the levels of which are similar in the two species. Rapid progressive infections are associated with a severe impairment in SIV-specific antibody production. While we did not find major differences in avidity and maturation between the pathogenic and nonpathogenic SIV infections, we identified a major difference in conformational epitope recognition, with the nonpathogenic infection being characterized by an evolution from low to high conformations. B cell dysfunction should be considered in designing immunization strategies aimed at preventing HIV disease progression. Copyright © 2017 American Society for Microbiology.

Immune Cells Link Obesity-associated Type 2 Diabetes and Periodontitis

PubMed Central

Zhu, M.; Nikolajczyk, B.S.

2014-01-01

The clinical association between obesity-associated type 2 diabetes (T2D) and periodontitis, coupled with the increasing prevalence of these diseases, justifies studies to identify mechanisms responsible for the vicious feed-forward loop between systemic and oral disease. Changes in the immune system are critical for both obesity-associated T2D and periodontitis and therefore may link these diseases. Recent studies at the intersection of immunology and metabolism have greatly advanced our understanding of the role the immune system plays in the transition between obesity and obesity-associated T2D and have shown that immune cells exhibit similar functional changes in obesity/T2D and periodontitis. Furthermore, myeloid and lymphoid cells likely synergize to promote obesity/T2D-associated periodontitis despite complexities introduced by disease interaction. Thus the groundwork is being laid for researchers to exploit existing models to understand immune cell dysfunction and break the devastating relationship between obesity-associated T2D and oral disease. PMID:24393706

Protein tyrosine phosphatase non-receptor type 2 and inflammatory bowel disease.

PubMed

Spalinger, Marianne R; McCole, Declan F; Rogler, Gerhard; Scharl, Michael

2016-01-21

Genome wide association studies have associated single nucleotide polymorphisms within the gene locus encoding protein tyrosine phosphatase non-receptor type 2 (PTPN2) with the onset of inflammatory bowel disease (IBD) and other inflammatory disorders. Expression of PTPN2 is enhanced in actively inflamed intestinal tissue featuring a marked up-regulation in intestinal epithelial cells. PTPN2 deficient mice suffer from severe intestinal and systemic inflammation and display aberrant innate and adaptive immune responses. In particular, PTPN2 is involved in the regulation of inflammatory signalling cascades, and critical for protecting intestinal epithelial barrier function, regulating innate and adaptive immune responses, and finally for maintaining intestinal homeostasis. On one hand, dysfunction of PTPN2 has drastic effects on innate host defence mechanisms, including increased secretion of pro-inflammatory cytokines, limited autophagosome formation in response to invading pathogens, and disruption of the intestinal epithelial barrier. On the other hand, PTPN2 function is crucial for controlling adaptive immune functions, by regulating T cell proliferation and differentiation as well as maintaining T cell tolerance. In this way, dysfunction of PTPN2 contributes to the manifestation of IBD. The aim of this review is to present an overview of recent findings on the role of PTPN2 in intestinal homeostasis and the impact of dysfunctional PTPN2 on intestinal inflammation.

Spaceflight Causes Increased Virulence of Serratia Marcescens on a Drosophila Melanogaster Host

NASA Technical Reports Server (NTRS)

Bhattacharya, Sharmila; Wade, William; Clemens-Grisham, Rachel; Hosamani, Ravikumar; Bhardwaj, Shilpa R.; Lera, Matthew P.; Gresser, Amy L.

2015-01-01

Drosophila melanogaster, or the fruit fly, has long been an important organism for Earth-based research, and is now increasingly utilized as a model system to understand the biological effects of spaceflight. Studies in Drosophila melanogaster have shown altered immune responses in 3rd instar larvae and adult males following spaceflight, changes similar to those observed in astronauts. In addition, spaceflight has also been shown to affect bacterial physiology, as evidenced by studies describing altered virulence of Salmonella typhimurium following spaceflight and variation in biofilm growth patterns for the opportunistic pathogen Pseudomonas aeruginosa during flight. We recently sent Serratia marcescens Db11, a Drosophila pathogen and an opportunistic human pathogen, to the ISS on SpaceX-5 (Fruit Fly Lab-01). S. marcescens samples were stored at 4degC for 24 days on-orbit and then allowed to grow for 120 hours at ambient station temperature before being returned to Earth. Upon return, bacteria were isolated and preserved in 50% glycerol or RNAlater. Storage, growth, and isolation for ground control samples were performed using the same procedures. Spaceflight and ground samples stored in 50% glycerol were diluted and injected into 5-7-day-old ground-born adult D. melanogaster. Lethality was significantly greater in flies injected with the spaceflight samples compared to those injected with ground bacterial samples. These results indicate a shift in the virulence profile of the spaceflight S. marcescens Db11 and will be further assessed with molecular biological analyses. Our findings strengthen the conclusion that spaceflight impacts the virulence of bacterial pathogens on model host organisms such as the fruit fly. This research was supported by NASA's ISS Program Office (ISSPO) and Space Life and Physical Sciences Research and Applications (SLPSRA).

Integrated Immunomodulatory Mechanisms through which Long-Chain n-3 Polyunsaturated Fatty Acids Attenuate Obese Adipose Tissue Dysfunction

PubMed Central

Liddle, Danyelle M.; Wellings, Hannah R.; Power, Krista A.; Robinson, Lindsay E.; Monk, Jennifer M.

2017-01-01

Obesity is a global health concern with rising prevalence that increases the risk of developing other chronic diseases. A causal link connecting overnutrition, the development of obesity and obesity-associated co-morbidities is visceral adipose tissue (AT) dysfunction, characterized by changes in the cellularity of various immune cell populations, altered production of inflammatory adipokines that sustain a chronic state of low-grade inflammation and, ultimately, dysregulated AT metabolic function. Therefore, dietary intervention strategies aimed to halt the progression of obese AT dysfunction through any of the aforementioned processes represent an important active area of research. In this connection, fish oil-derived dietary long-chain n-3 polyunsaturated fatty acids (PUFA) in the form of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been demonstrated to attenuate obese AT dysfunction through multiple mechanisms, ultimately affecting AT immune cellularity and function, adipokine production, and metabolic signaling pathways, all of which will be discussed herein. PMID:29186929

Triactome: Neuro–Immune–Adipose Interactions. Implication in Vascular Biology

PubMed Central

Chaldakov, George Nikov; Fiore, Marco; Ghenev, Peter I.; Beltowski, Jerzy; Ranćić, Gorana; Tunçel, Neşe; Aloe, Luigi

2014-01-01

Understanding how the precise interactions of nerves, immune cells, and adipose tissue account for cardiovascular and metabolic biology is a central aim of biomedical research at present. A long standing paradigm holds that the vascular wall is composed of three concentric tissue coats (tunicae): intima, media, and adventitia. However, large- and medium-sized arteries, where usually atherosclerotic lesions develop, are consistently surrounded by periadventitial adipose tissue (PAAT), we recently designated tunica adiposa (in brief, adiposa like intima, media, and adventitia). Today, atherosclerosis is considered an immune-mediated inflammatory disease featured by endothelial dysfunction/intimal thickening, medial atrophy, and adventitial lesions associated with adipose dysfunction, whereas hypertension is characterized by hyperinnervation-associated medial thickening due to smooth muscle cell hypertrophy/hyperplasia. PAAT expansion is associated with increased infiltration of immune cells, both adipocytes and immunocytes secreting pro-inflammatory and anti-inflammatory (metabotrophic) signaling proteins collectively dubbed adipokines. However, the role of vascular nerves and their interactions with immune cells and paracrine adipose tissue is not yet evaluated in such an integrated way. The present review attempts to briefly highlight the findings in basic and translational sciences in this area focusing on neuro–immune–adipose interactions, herein referred to as triactome. Triactome-targeted pharmacology may provide a novel therapeutic approach in cardiovascular disease. PMID:24782857

Increased T Cell Immunosenescence and Accelerated Maturation Phenotypes in Older Kidney Transplant Recipients.

PubMed

Schaenman, J M; Rossetti, M; Sidwell, T; Groysberg, V; Sunga, G; Korin, Y; Liang, E; Zhou, X; Abdallah, B; Lum, E; Bunnapradist, S; Pham, T; Danovitch, G; Reed, E F

2018-06-15

Older kidney transplant recipients experience increased rates of infection and death, and less rejection, compared with younger patients. However, little is known about immune dysfunction in older compared with younger kidney transplant recipients and whether it is associated with infection. We evaluated T cell phenotypes including maturation, immune senescence, and exhaustion in a novel investigation into differences in older compared with younger patients receiving identical immune suppression regimens. We evaluated PBMC from 60 kidney transplant recipients (23 older and 37 matched younger patients) by multiparameter immune phenotyping. Older kidney transplant recipients demonstrated decreased frequency of naïve CD4+ and CD8+ T cells, and increased frequency of terminally differentiated, immune senescent, and NK T cells expressing KLRG1. There was a trend towards increased frequency of T cell immune senescence in patients experiencing infection in the first year after transplantation, which reached statistical significance in a multivariate analysis. This pilot study reveals immune dysfunction in older compared with younger transplant recipients, and suggests a likely mechanism for increased vulnerability to infection. The ability to assess T cell maturation and immune senescence in transplant recipients offers the potential for risk stratification and customization of immune suppression to prevent infection and rejection after transplantation. Copyright © 2018. Published by Elsevier Inc.

Infectious Disease Risk Associated with Space Flight

NASA Technical Reports Server (NTRS)

Pierson, Duane L.

2010-01-01

This slide presentation opens with views of the shuttle in various stages of preparation for launch, a few moments after launch prior to external fuel tank separation, a few pictures of the earth,and several pictures of astronomical interest. The presentation reviews the factors effecting the risks of infectious disease during space flight, such as the crew, water, food, air, surfaces and payloads and the factors that increase disease risk, the factors affecting the risk of infectious disease during spaceflight, and the environmental factors affecting immunity, such as stress. One factor in space infectious disease is latent viral reactivation, such as herpes. There are comparisons of the incidence of viral reactivation in space, and in other analogous situations (such as bed rest, or isolation). There is discussion of shingles, and the pain and results of treatment. There is a further discussion of the changes in microbial pathogen characteristics, using salmonella as an example of the increased virulence of microbes during spaceflight. A factor involved in the risk of infectious disease is stress.

Spaceflight alters immune cell function and distribution

NASA Technical Reports Server (NTRS)

Sonnenfeld, Gerald; Mandel, Adrian D.; Konstantinova, Irina V.; Berry, Wallace D.; Taylor, Gerald R.; Lesniak, A. T.; Fuchs, Boris B.; Rakhmilevich, Alexander L.

1992-01-01

Experiments are described which were performed onboard Cosmos 2044 to determine spaceflight effects on immunologically important cell function and distribution. Results indicate that bone marrow cells from flown and suspended rats exhibited a decreased response to a granulocyte/monocyte colony-stimulating factor compared with the bone marrow cells from control rats. Bone marrow cells showed an increase in the percentage of cells expressing markers for helper T-cells in the myelogenous population and increased percentages of anti-asialo granulocyte/monocyte-1-bearing interleulin-2 receptor bearing pan T- and helper T-cells in the lymphocytic population.

Development and validation of immune dysfunction score to predict 28-day mortality of sepsis patients

PubMed Central

Fang, Wen-Feng; Douglas, Ivor S.; Chen, Yu-Mu; Lin, Chiung-Yu; Kao, Hsu-Ching; Fang, Ying-Tang; Huang, Chi-Han; Chang, Ya-Ting; Huang, Kuo-Tung; Wang, Yi-His; Wang, Chin-Chou

2017-01-01

Background Sepsis-induced immune dysfunction ranging from cytokines storm to immunoparalysis impacts outcomes. Monitoring immune dysfunction enables better risk stratification and mortality prediction and is mandatory before widely application of immunoadjuvant therapies. We aimed to develop and validate a scoring system according to patients’ immune dysfunction status for 28-day mortality prediction. Methods A prospective observational study from a cohort of adult sepsis patients admitted to ICU between August 2013 and June 2016 at Kaohsiung Chang Gung Memorial Hospital in Taiwan. We evaluated immune dysfunction status through measurement of baseline plasma Cytokine levels, Monocyte human leukocyte-DR expression by flow cytometry, and stimulated immune response using post LPS stimulated cytokine elevation ratio. An immune dysfunction score was created for 28-day mortality prediction and was validated. Results A total of 151 patients were enrolled. Data of the first consecutive 106 septic patients comprised the training cohort, and of other 45 patients comprised the validation cohort. Among the 106 patients, 21 died and 85 were still alive on day 28 after ICU admission. (mortality rate, 19.8%). Independent predictive factors revealed via multivariate logistic regression analysis included segmented neutrophil-to-monocyte ratio, granulocyte-colony stimulating factor, interleukin-10, and monocyte human leukocyte antigen-antigen D–related levels, all of which were selected to construct the score, which predicted 28-day mortality with area under the curve of 0.853 and 0.789 in the training and validation cohorts, respectively. Conclusions The immune dysfunction scoring system developed here included plasma granulocyte-colony stimulating factor level, interleukin-10 level, serum segmented neutrophil-to-monocyte ratio, and monocyte human leukocyte antigen-antigen D–related expression appears valid and reproducible for predicting 28-day mortality. PMID:29073262

Spaceflight and immune responses of Rhesus monkeys

NASA Technical Reports Server (NTRS)

Sonnenfeld, Gerald

1994-01-01

Evidence from both human and rodent studies indicates that alterations in immunological parameters occur after space flight. The objective of this project is to determine the effects of space flight on immune responses of Rhesus monkeys. The expected significance of the work is a determination of the range of immunological functions of the Rhesus monkey, a primate similar in many ways to man, affected by space flight. Changes in immune responses that could yield alterations in resistance to infection may be determined as well as the duration of alterations in immune responses. Additional information on the nature of cellular interactions for the generation of immune responses may also be obtained.

Physiological Aging: Links Among Adipose Tissue Dysfunction, Diabetes, and Frailty.

PubMed

Stout, Michael B; Justice, Jamie N; Nicklas, Barbara J; Kirkland, James L

2017-01-01

Advancing age is associated with progressive declines in physiological function that lead to overt chronic disease, frailty, and eventual mortality. Importantly, age-related physiological changes occur in cellularity, insulin-responsiveness, secretory profiles, and inflammatory status of adipose tissue, leading to adipose tissue dysfunction. Although the mechanisms underlying adipose tissue dysfunction are multifactorial, the consequences result in secretion of proinflammatory cytokines and chemokines, immune cell infiltration, an accumulation of senescent cells, and an increase in senescence-associated secretory phenotype (SASP). These processes synergistically promote chronic sterile inflammation, insulin resistance, and lipid redistribution away from subcutaneous adipose tissue. Without intervention, these effects contribute to age-related systemic metabolic dysfunction, physical limitations, and frailty. Thus adipose tissue dysfunction may be a fundamental contributor to the elevated risk of chronic disease, disability, and adverse health outcomes with advancing age. ©2017 Int. Union Physiol. Sci./Am. Physiol. Soc.

Use of bed rest and head-down tilt to simulate spaceflight-induce immune system changes

NASA Technical Reports Server (NTRS)

Schmitt, D. A.; Schaffar, L.; Taylor, G. R.; Loftin, K. C.; Schneider, V. S.; Koebel, A.; Abbal, M.; Sonnenfeld, G.; Lewis, D. E.; Reuben, J. R.;

Dysfunctional brain-bone marrow communication: a paradigm shift in the pathophysiology of hypertension.

PubMed

Santisteban, Monica M; Zubcevic, Jasenka; Baekey, David M; Raizada, Mohan K

2013-08-01

It is widely accepted that the pathophysiology of hypertension involves autonomic nervous system dysfunction, as well as a multitude of immune responses. However, the close interplay of these systems in the development and establishment of high blood pressure and its associated pathophysiology remains elusive and is the subject of extensive investigation. It has been proposed that an imbalance of the neuro-immune systems is a result of an enhancement of the "proinflammatory sympathetic" arm in conjunction with dampening of the "anti-inflammatory parasympathetic" arm of the autonomic nervous system. In addition to the neuronal modulation of the immune system, it is proposed that key inflammatory responses are relayed back to the central nervous system and alter the neuronal communication to the periphery. The overall objective of this review is to critically discuss recent advances in the understanding of autonomic immune modulation, and propose a unifying hypothesis underlying the mechanisms leading to the development and maintenance of hypertension, with particular emphasis on the bone marrow, as it is a crucial meeting point for neural, immune, and vascular networks.

Dysfunctional brain-bone marrow communication: A paradigm shift in the pathophysiology of hypertension

PubMed Central

Santisteban, Monica M.; Zubcevic, Jasenka; Baekey, David M.; Raizada, Mohan K.

2013-01-01

It is widely accepted that the pathophysiology of hypertension involves autonomic nervous system dysfunction, as well as a multitude of immune responses. However, the close interplay of these systems in the development and establishment of high blood pressure and its associated pathophysiology remains elusive and is the subject of extensive investigation. It has been proposed that an imbalance of the neuro-immune systems is a result of an enhancement of the “pro-inflammatory sympathetic” arm in conjunction with dampening of the “anti-inflammatory parasympathetic” arm of the autonomic nervous system. In addition to the neuronal modulation of the immune system, it is proposed that key inflammatory responses are relayed back to the central nervous system and alter the neuronal communication to the periphery. The overall objective of this review is to critically discuss recent advances in the understanding of autonomic immune modulation, and propose a unifying hypothesis underlying the mechanisms leading to the development and maintenance of hypertension, with particular emphasis on the bone marrow, as it is a crucial meeting point for neural, immune, and vascular networks. PMID:23715920

Epigenetics Research on the International Space Station

NASA Technical Reports Server (NTRS)

Love, John; Cooley, Vic

2016-01-01

The International Space Station (ISS) is a state-of-the orbiting laboratory focused on advancing science and technology research. Experiments being conducted on the ISS include investigations in the emerging field of Epigenetics. Epigenetics refers to stably heritable changes in gene expression or cellular phenotype (the transcriptional potential of a cell) resulting from changes in a chromosome without alterations to the underlying DNA nucleotide sequence (the genetic code), which are caused by external or environmental factors, such as spaceflight microgravity. Molecular mechanisms associated with epigenetic alterations regulating gene expression patterns include covalent chemical modifications of DNA (e.g., methylation) or histone proteins (e.g., acetylation, phorphorylation, or ubiquitination). For example, Epigenetics ("Epigenetics in Spaceflown C. elegans") is a recent JAXA investigation examining whether adaptations to microgravity transmit from one cell generation to another without changing the basic DNA of the organism. Mouse Epigenetics ("Transcriptome Analysis and Germ-Cell Development Analysis of Mice in Space") investigates molecular alterations in organ-specific gene expression patterns and epigenetic modifications, and analyzes murine germ cell development during long term spaceflight, as well as assessing changes in offspring DNA. NASA's first foray into human Omics research, the Twins Study ("Differential effects of homozygous twin astronauts associated with differences in exposure to spaceflight factors"), includes investigations evaluating differential epigenetic effects via comprehensive whole genome analysis, the landscape of DNA and RNA methylation, and biomolecular changes by means of longitudinal integrated multi-omics research. And the inaugural Genes in Space student challenge experiment (Genes in Space-1) is aimed at understanding how epigenetics plays a role in immune system dysregulation by assaying DNA methylation in immune cells directly in space using miniPCR technology. In addition, NASA's geneLAB campaign covers the epigenome as part of the "expressome", by employing an innovative open source science platform for multi-investigator high throughput utilization of the ISS. Earth benefits of Epigenetics research onboard the ISS range from contributions to the fundamental understanding of epigenetic phenomena with applications in countermeasure development for biomedical conditions, to the generation of integrated strategies for personalized medicine based on unique physiological responses.

Immune Regulation during Chronic Visceral Leishmaniasis

PubMed Central

Faleiro, Rebecca J.; Kumar, Rajiv; Hafner, Louise M.; Engwerda, Christian R.

2014-01-01

Visceral leishmaniasis is a chronic parasitic disease associated with severe immune dysfunction. Treatment options are limited to relatively toxic drugs, and there is no vaccine for humans available. Hence, there is an urgent need to better understand immune responses following infection with Leishmania species by studying animal models of disease and clinical samples from patients. Here, we review recent discoveries in these areas and highlight shortcomings in our knowledge that need to be addressed if better treatment options are to be developed and effective vaccines designed. PMID:25010815

Oxidative stress activates endothelial innate immunity via sterol regulatory element binding protein 2 (SREBP2) transactivation of microRNA-92a.

PubMed

Chen, Zhen; Wen, Liang; Martin, Marcy; Hsu, Chien-Yi; Fang, Longhou; Lin, Feng-Mao; Lin, Ting-Yang; Geary, McKenna J; Geary, Greg G; Zhao, Yongli; Johnson, David A; Chen, Jaw-Wen; Lin, Shing-Jong; Chien, Shu; Huang, Hsien-Da; Miller, Yury I; Huang, Po-Hsun; Shyy, John Y-J

2015-03-03

Oxidative stress activates endothelial innate immunity and disrupts endothelial functions, including endothelial nitric oxide synthase-derived nitric oxide bioavailability. Here, we postulated that oxidative stress induces sterol regulatory element-binding protein 2 (SREBP2) and microRNA-92a (miR-92a), which in turn activate endothelial innate immune response, leading to dysfunctional endothelium. Using cultured endothelial cells challenged by diverse oxidative stresses, hypercholesterolemic zebrafish, and angiotensin II-infused or aged mice, we demonstrated that SREBP2 transactivation of microRNA-92a (miR-92a) is oxidative stress inducible. The SREBP2-induced miR-92a targets key molecules in endothelial homeostasis, including sirtuin 1, Krüppel-like factor 2, and Krüppel-like factor 4, leading to NOD-like receptor family pyrin domain-containing 3 inflammasome activation and endothelial nitric oxide synthase inhibition. In endothelial cell-specific SREBP2 transgenic mice, locked nucleic acid-modified antisense miR-92a attenuates inflammasome, improves vasodilation, and ameliorates angiotensin II-induced and aging-related atherogenesis. In patients with coronary artery disease, the level of circulating miR-92a is inversely correlated with endothelial cell-dependent, flow-mediated vasodilation and is positively correlated with serum level of interleukin-1β. Our findings suggest that SREBP2-miR-92a-inflammasome exacerbates endothelial dysfunction during oxidative stress. Identification of this mechanism may help in the diagnosis or treatment of disorders associated with oxidative stress, innate immune activation, and endothelial dysfunction. © 2014 American Heart Association, Inc.

Effects of Spaceflight on Cells of Bone Marrow Origin

PubMed Central

Özçivici, Engin

2013-01-01

Once only a subject for science fiction novels, plans for establishing habitation on space stations, the Moon, and distant planets now appear among the short-term goals of space agencies. This article reviews studies that present biomedical issues that appear to challenge humankind for long-term spaceflights. With particularly focus on cells of bone marrow origin, studies involving changes in bone, immune, and red blood cell populations and their functions due to extended weightlessness were reviewed. Furthermore, effects of mechanical disuse on primitive stem cells that reside in the bone marrow were also included in this review. Novel biomedical solutions using space biotechnology will be required in order to achieve the goal of space exploration without compromising the functions of bone marrow, as spaceflight appears to disrupt homeostasis for all given cell types. Conflict of interest:None declared. PMID:24385745

Experiment K-7-22: Growth Hormone Regulation Synthesis and Secretion in Microgravity. Part 1; Growth Hormone Regulation Synthesis and Secretion in Microgravity

NASA Technical Reports Server (NTRS)

Hymer, W. C.; Grindeland, R.; Vale, W.; Sawchenko, P.; Ilyina-Kakueva, E. I.

1994-01-01

Changes in the musculoskeletal, immune, vascular, and endocrine system of the rat occur as a result of short-term spaceflight. Since pituitary gland growth hormone (GH) plays a role in the control of these systems, and since the results of an earlier spaceflight mission (Spacelab 3, 1985) showed that GH cell function was compromised in a number of post-flight tests, we repeated and extended the 1985 experiment in two subsequent spaceflights: the 12.5 day mission of Cosmos 1887 (in 1987) and the 14 day mission of Cosmos 2044 (in 1989). The results of these later two flight experiments are the subject of this report. They document repeatable and significant changes in the GH cell system of the spaceflown rat in several post-flight tests.

Effects of spaceflight on murine skeletal muscle gene expression

PubMed Central

Allen, David L.; Bandstra, Eric R.; Harrison, Brooke C.; Thorng, Seiha; Stodieck, Louis S.; Kostenuik, Paul J.; Morony, Sean; Lacey, David L.; Hammond, Timothy G.; Leinwand, Leslie L.; Argraves, W. Scott; Bateman, Ted A.; Barth, Jeremy L.

2009-01-01

Spaceflight results in a number of adaptations to skeletal muscle, including atrophy and shifts toward faster muscle fiber types. To identify changes in gene expression that may underlie these adaptations, we used both microarray expression analysis and real-time polymerase chain reaction to quantify shifts in mRNA levels in the gastrocnemius from mice flown on the 11-day, 19-h STS-108 shuttle flight and from normal gravity controls. Spaceflight data also were compared with the ground-based unloading model of hindlimb suspension, with one group of pure suspension and one of suspension followed by 3.5 h of reloading to mimic the time between landing and euthanization of the spaceflight mice. Analysis of microarray data revealed that 272 mRNAs were significantly altered by spaceflight, the majority of which displayed similar responses to hindlimb suspension, whereas reloading tended to counteract these responses. Several mRNAs altered by spaceflight were associated with muscle growth, including the phosphatidylinositol 3-kinase regulatory subunit p85α, insulin response substrate-1, the forkhead box O1 transcription factor, and MAFbx/atrogin1. Moreover, myostatin mRNA expression tended to increase, whereas mRNA levels of the myostatin inhibitor FSTL3 tended to decrease, in response to spaceflight. In addition, mRNA levels of the slow oxidative fiber-associated transcriptional coactivator peroxisome proliferator-associated receptor (PPAR)-γ coactivator-1α and the transcription factor PPAR-α were significantly decreased in spaceflight gastrocnemius. Finally, spaceflight resulted in a significant decrease in levels of the microRNA miR-206. Together these data demonstrate that spaceflight induces significant changes in mRNA expression of genes associated with muscle growth and fiber type. PMID:19074574

Studies of Cell-Mediated Immunity Against Immune Disorders Using Synthetic Peptides and Rotating Bioreactor System

NASA Technical Reports Server (NTRS)

Sastry, Jagannadha K.

1998-01-01

We conducted a series of experiments using mouse immune-precursor cells, and observed that bioreactor culturing results in the loss of antigen-specific cytotoxic T lymphocyte (CTL) function. The reason for the abrogation of CTL function is microgravity conditions in the bioreactor, but not the antigen per se or its MHC restriction. Similarly, we observed that allostimulation of human PBMC in the bioreactor, but not in the T flask, resulted in the blunting of both allo-CTL function and the NK activity, indicating that the microgravity-associated functional defects are not unique to the mouse system. These results provide further confirmation to the microgravity-associated immune dysfunction, and constitute ground-based confirmatory data for those related to space-travel.

The use of decompression to simulate the effect of extravehicular activity on human lymphocyte transformation

NASA Technical Reports Server (NTRS)

Meehan, R. T.; Duncan, U.; Neale, L.; Waligora, J.; Taylor, G. R.

1986-01-01

Lymphocytes from 35 subjects participating in a chamber study simulating extravehicular activity (EVA) conditions were studied. No significant differences in H3 thymidine uptake between pre chamber and post chamber response to any mitogens autologous plasma, or among circulating mononuclear cells by flow cytometry are observed. The studies could not identify the subjects who developed venous bubbles. Data from eight subjects suggests that acute stress associated with participating in the study augments in vitro lymphocyte proliferation. Results indicate EVA exposure does not greatly influence space-flight induced alterations in immune effector cell function.

Parasitic nematode-induced modulation of body weight and associated metabolic dysfunction in mouse models of obesity

USDA-ARS?s Scientific Manuscript database

Obesity is associated with a chronic low grade inflammation characterized by high level of pro-inflammatory cytokines and mediators implicated in disrupted metabolic homeostasis. Parasitic nematode infection induces a polarized Th2 cytokine response and has been shown to modulate immune-based pathol...

HIV-1, Reactive Oxygen Species and Vascular Complications

PubMed Central

Porter, Kristi M.; Sutliff, Roy L.

2012-01-01

Over 1 million people in the United States and 33 million individuals worldwide suffer from HIV/AIDS. Since its discovery, HIV/AIDS has been associated with an increased susceptibility to opportunistic infection due to immune dysfunction. Highly active antiretroviral therapies (HAART) restore immune function and, as a result, people infected with HIV-1 are living longer. This improved survival of HIV-1 patients has revealed a previously unrecognized risk of developing vascular complications, such as atherosclerosis and pulmonary hypertension. The mechanisms underlying these HIV-associated vascular disorders are poorly understood. However, HIV-induced elevations in reactive oxygen species, including superoxide and hydrogen peroxide, may contribute to vascular disease development and progression by altering cell function and redox-sensitive signaling pathways. In this review, we summarize the clinical and experimental evidence demonstrating HIV- and HIV antiretroviral therapy-induced alterations in reactive oxygen species (ROS) and how these effects likely contribute to vascular dysfunction and disease. PMID:22564529

Microbial Risk Assessment

NASA Technical Reports Server (NTRS)

Ott, C. M.; Mena, K. D.; Nickerson, C.A.; Pierson, D. L.

2009-01-01

Historically, microbiological spaceflight requirements have been established in a subjective manner based upon expert opinion of both environmental and clinical monitoring results and the incidence of disease. The limited amount of data, especially from long-duration missions, has created very conservative requirements based primarily on the concentration of microorganisms. Periodic reevaluations of new data from later missions have allowed some relaxation of these stringent requirements. However, the requirements remain very conservative and subjective in nature, and the risk of crew illness due to infectious microorganisms is not well defined. The use of modeling techniques for microbial risk has been applied in the food and potable water industries and has exceptional potential for spaceflight applications. From a productivity standpoint, this type of modeling can (1) decrease unnecessary costs and resource usage and (2) prevent inadequate or inappropriate data for health assessment. In addition, a quantitative model has several advantages for risk management and communication. By identifying the variable components of the model and the knowledge associated with each component, this type of modeling can: (1) Systematically identify and close knowledge gaps, (2) Systematically identify acceptable and unacceptable risks, (3) Improve communication with stakeholders as to the reasons for resource use, and (4) Facilitate external scientific approval of the NASA requirements. The modeling of microbial risk involves the evaluation of several key factors including hazard identification, crew exposure assessment, dose-response assessment, and risk characterization. Many of these factors are similar to conditions found on Earth; however, the spaceflight environment is very specialized as the inhabitants live in a small, semi-closed environment that is often dependent on regenerative life support systems. To further complicate modeling efforts, microbial dose-response characteristics may be affected by a potentially dysfunctional crew immune system during a mission. In addition, microbial virulence has been shown to change under certain conditions during spaceflight, further complicating dose-response characterization. An initial study of the applicability of microbial risk assessment techniques was performed using Crew Health Care System (CHeCS) operational data from the International Space Station potable water systems. The risk of infection from potable water was selected as the flight systems and microbial ecology are well defined. This initial study confirmed the feasibility of using microbial risk assessment modeling for spaceflight systems. While no immediate threat was detected, the study identified several medically significant microorganisms that could pose a health risk if uncontrolled. The study also identified several specific knowledge gaps in making a risk assessment and noted that filling these knowledge gaps is essential as the risk estimates may change by orders of magnitude depending on the answers. The current phase of the microbial risk assessment studies focuses on the dose-response relationship of specific infectious agents, focusing on Salmonella enterica Typhimurium, Pseudomonas spp., and Escherichia coli, as their evaluation will provide a better baseline for determining the overall hazard characterization. The organisms were chosen as they either have been isolated on spacecraft or have an identified route of infection during a mission. The characterization will utilize dose-response models selected either from the peer-reviewed literature and/or by using statistical approaches. Development of these modeling and risk assessment techniques will help to optimize flight requirements and to protect the safety, health, and performance of the crew.

Effect of space flight on interferon production - mechanistic studies

NASA Technical Reports Server (NTRS)

Sonnenfeld, Gerald

1991-01-01

Ground-based models were studied for the effects of space flight on immune responses. Most time was spent on the model for the antiorthostatic, hypokinetic, hypodynamic suspension model for rats. Results indicate that suspension is useful for modeling the effects of spaceflight on functional immune responses, such as interferon and interleukin production. It does not appear to be useful for modeling shifts in leukocyte sub-populations. Calcium and 1,25-dihydroxyvitamin D sub 3 appear to play a pivitol role in regulating shifts in immune responses due to suspension. The macrophage appears to be an important target cell for the effects of suspension on immune responses.

Neuroimmune Interactions: From the Brain to the Immune System and Vice Versa.

PubMed

Dantzer, Robert

2018-01-01

Because of the compartmentalization of disciplines that shaped the academic landscape of biology and biomedical sciences in the past, physiological systems have long been studied in isolation from each other. This has particularly been the case for the immune system. As a consequence of its ties with pathology and microbiology, immunology as a discipline has largely grown independently of physiology. Accordingly, it has taken a long time for immunologists to accept the concept that the immune system is not self-regulated but functions in close association with the nervous system. These associations are present at different levels of organization. At the local level, there is clear evidence for the production and use of immune factors by the central nervous system and for the production and use of neuroendocrine mediators by the immune system. Short-range interactions between immune cells and peripheral nerve endings innervating immune organs allow the immune system to recruit local neuronal elements for fine tuning of the immune response. Reciprocally, immune cells and mediators play a regulatory role in the nervous system and participate in the elimination and plasticity of synapses during development as well as in synaptic plasticity at adulthood. At the whole organism level, long-range interactions between immune cells and the central nervous system allow the immune system to engage the rest of the body in the fight against infection from pathogenic microorganisms and permit the nervous system to regulate immune functioning. Alterations in communication pathways between the immune system and the nervous system can account for many pathological conditions that were initially attributed to strict organ dysfunction. This applies in particular to psychiatric disorders and several immune-mediated diseases. This review will show how our understanding of this balance between long-range and short-range interactions between the immune system and the central nervous system has evolved over time, since the first demonstrations of immune influences on brain functions. The necessary complementarity of these two modes of communication will then be discussed. Finally, a few examples will illustrate how dysfunction in these communication pathways results in what was formerly considered in psychiatry and immunology to be strict organ pathologies.

Altered Cytokine Production By Specific Human Peripheral Blood Cell Subsets Immediately Following Spaceflight

NASA Technical Reports Server (NTRS)

Crucian, Brian E.; Cubbage, Michael L.; Sams, Clarence F.

1999-01-01

In this study, we have attempted to combine standard immunological assays with the cellular resolving power of the flow cytometer to positively identify the specific cell types involved in spaceflight-induced immune alterations. We have obtained whole blood samples from 27 astronauts collected at three timepoints (L-10, R+0 and R+3) surrounding four recent space shuttle missions. The duration of these missions ranged from 10 to 18 days. Assays performed included serum/urine cortisol, comprehensive subset phenotyping, assessment of cellular activation markers and intracellular cytokine production following mitogenic stimulation. Absolute levels of peripheral granulocytes were significantly elevated following spaceflight, but the levels of circulating lymphocytes and monocytes were unchanged. Lymphocyte subset analysis demonstrated trends towards a decreased percentage of T cells and an increased percentage of B cells. Nearly all of the astronauts exhibited an increased CD4:CD8 ratio, which was dramatic in some individuals. Assessment of memory (CD45RA+) vs. naive (CD45RO+) CD4+ T cell subsets was more ambiguous, with subjects tending to group more as a flight crew. All subjects from one mission demonstrated an increased CD45RA:CD45RO ratio, while all subjects from another Mission demonstrated a decreased ratio. While no significant trend was seen in the monocyte population as defined by scatter, a decreased percentage of the CD14+ CD16+ monocyte subset was seen following spaceflight in all subjects tested. In general, most of the cellular changes described above which were assessed at R+O and compared to L-10 trended to pre-flight levels by R+3. Although no significant differences were seen in the expression of the cellular activation markers CD69 and CD25 following exposure to microgravity, significant alterations were seen in cytokine production in response to mitogenic activation for specific subsets. T cell (CD3+) production of IL-2 was significantly decreased after at R+O as was IL-2 production by both CD4+ and CD8+ T cell subsets for most subjects. Production of IFN(sub gamma) did not appear to be affected by microgravity exposure in either T cells in general or in the CD8+ T cell subset. There was a spaceflight-induced decrease in IFN(sub gamma) production in the CD4+ T cell subset, however it did not reach statistical significance. Serum and urine stress-hormone analysis indicated significant physiologic stresses in astronauts following spaceflight. In summary, these results demonstrate alterations in the peripheral immune system of astronauts immediately after spaceflight of 10 to 18 days duration and support continued research regarding microgravity and immunology (including in-flight sampling) prior to routine long-term spaceflight for astronauts.

The ISS flight of Richard Garriott: a template for medicine and science investigation on future spaceflight participant missions.

PubMed

Jennings, Richard T; Garriott, Owen K; Bogomolov, Valery V; Pochuev, Vladimir I; Morgun, Valery V; Garriott, Richard A

2010-02-01

A total of eight commercial spaceflight participants have launched to the International Space Station (ISS) on Soyuz vehicles. Based on an older mean age compared to career astronauts and an increased prevalence of medical conditions, spaceflight participants have provided the opportunity to learn about the effect of space travel on crewmembers with medical problems. The 12-d Soyuz TMA-13/12 ISS flight of spaceflight participant Richard Garriott included medical factors that required preflight intervention, risk mitigation strategies, and provided the opportunity for medical study on-orbit. Equally important, Mr. Garriott conducted extensive medical, scientific, and educational payload operations during the flight. These included 7 medical experiments and a total of 15 scientific projects such as protein crystal growth, Earth observations/photography, educational projects with schools, and amateur radio. The medical studies included the effect of microgravity on immune function, sleep, bone loss, corneal refractive surgery, low back pain, motion perception, and intraocular pressure. The overall mission success resulted from non-bureaucratic agility in mission planning, cooperation with investigators from NASA, ISS, International Partners, and the Korean Aerospace Research Institute, in-flight support and leadership from a team with spaceflight and Capcom experience, and overall mission support from the ISS program. This article focuses on science opportunities that suborbital and orbital spaceflight participant flights offer and suggests that the science program on Richard Garriott's flight be considered a model for future orbital and suborbital missions. The medical challenges are presented in a companion article.

The Immune System and Developmental Programming of Brain and Behavior

PubMed Central

Bilbo, Staci D.; Schwarz, Jaclyn M.

2012-01-01

The brain, endocrine, and immune systems are inextricably linked. Immune molecules have a powerful impact on neuroendocrine function, including hormone-behavior interactions, during health as well as sickness. Similarly, alterations in hormones, such as during stress, can powerfully impact immune function or reactivity. These functional shifts are evolved, adaptive responses that organize changes in behavior and mobilize immune resources, but can also lead to pathology or exacerbate disease if prolonged or exaggerated. The developing brain in particular is exquisitely sensitive to both endogenous and exogenous signals, and increasing evidence suggests the immune system has a critical role in brain development and associated behavioral outcomes for the life of the individual. Indeed, there are associations between many neuropsychiatric disorders and immune dysfunction, with a distinct etiology in neurodevelopment. The goal of this review is to describe the important role of the immune system during brain development, and to discuss some of the many ways in which immune activation during early brain development can affect the later-life outcomes of neural function, immune function, mood and cognition. PMID:22982535

Intradermal reactions to purified protein derivative in patients with diabetes mellitus.

PubMed

Nwabudike, L C; Ionescu-Tîrgovişte, C

2005-01-01

Diabetes mellitus is known to adversely affect the immune system. Immune dysfunction is also associated with the etiology of diabetes mellitus. Immune dysfunction is associated with diminished chemotactic, phagocytic and monocyte activity. There is also increased T-cell activity. All these are associated with acute hyperglycemia. We investigated the cellular arm of the immune system of patients with diabetes mellitus using intradermal reactions (IDR) to purified protein derivative (PPD). Both groups high blood glucose [HBG] vs. low blood glucose [LBG]) were homogeneous in terms of size and sex and average age (24. vs. 22.; 21 F vs 25 M; 56.5yrs. vs. 54.5 yrs.). The LBG had a greater average duration of diabetes (13.6 yrs vs. 9.3 yrs), which suggests an increased tendency to complications of diabetes mellitus. The results showed an average blood glucose and IDR (HBG vs. LBG) of 235.8 +/- 46.5 mg/dl vs. 144.3 +/- 26.7 mg/dl and 18.5 +/- 8.5 mm vs. 12.2 +/- 7.0 mm respectively. These results showed that IDR is significantly affected by hyperglycemia. This increased IDR may be a consequence of the synergy between interferon-gamma and tumor necrosis factor alpha which is a significant factor in diabetes. Also, there is an accentuation of this synergy following injection of PPD. It appears to be clear that IDR to PPD may be influenced by the diabetic state, especially acute hyperglycemia. However, it also appears that IDR to PPD may not be an adequate method for assessing cutaneous cell-mediated immunity.

Copolymer-1 enhances cognitive performance in young adult rats

PubMed Central

Meneses, Alfredo; Cruz-Martínez, Yolanda; Anaya-Jiménez, Rosa María; Liy-Salmerón, Gustavo; Carvajal, Horacio Guillermo; Ponce-López, Maria Teresa

2018-01-01

Cognitive impairment is a dysfunction observed as a sequel of various neurodegenerative diseases, as well as a concomitant element in the elderly stages of life. In clinical settings, this malfunction is identified as mild cognitive impairment. Previous studies have suggested that cognitive impairment could be the result of a reduction in the expression of brain-derived neurotrophic factor (BDNF) and/or immune dysfunction. Copolymer-1 (Cop-1) is an FDA-approved synthetic peptide capable of inducing the activation of Th2/3 cells, which are able to release BDNF, as well as to migrate and accumulate in the brain. In this study, we evaluated the effect of Cop-1 immunization on improvement of cognition in adult rats. For this purpose, we performed four experiments. We evaluated the effect of Cop-1 immunization on learning/memory using the Morris water maze for spatial memory and autoshaping for associative memory in 3- or 6-month-old rats. BDNF concentrations at the hippocampus were determined by ELISA. Cop-1 immunization induced a significant improvement of spatial memory and associative memory in 6-month-old rats. Likewise, Cop-1 improved spatial memory and associative memory when animals were immunized at 3 months and evaluated at 6 months old. Additionally, Cop-1 induced a significant increase in BDNF levels at the hippocampus. To our knowledge, the present investigation reports the first instance of Cop-1 treatment enhancing cognitive function in normal young adult rats, suggesting that Cop-1 may be a practical therapeutic strategy potentially useful for age- or disease-related cognitive impairment. PMID:29494605

Current insights into the innate immune system dysfunction in irritable bowel syndrome.

PubMed

Lazaridis, Nikolaos; Germanidis, Georgios

2018-01-01

Irritable bowel syndrome (IBS) is a functional bowel disorder associated with abdominal pain and alterations in bowel habits. The presence of IBS greatly impairs patients' quality of life and imposes a high economic burden on the community; thus, there is intense pressure to reveal its elusive pathogenesis. Many etiological mechanisms have been implicated, but the pathophysiology of the syndrome remains unclear. As a result, novel drug development has been slow and no pharmacological intervention is universally accepted. A growing evidence implicates the role of low-grade inflammation and innate immune system dysfunction, although contradictory results have frequently been presented. Mast cells (MC), eosinophils and other key immune cells together with their mediators seem to play an important role, at least in subgroups of IBS patients. Cytokine imbalance in the systematic circulation and in the intestinal mucosa may also characterize IBS presentation. Toll-like receptors and their emerging role in pathogen recognition have also been highlighted recently, as dysregulation has been reported to occur in patients with IBS. This review summarizes the current knowledge regarding the involvement of any immunological alteration in the development of IBS. There is substantial evidence to support innate immune system dysfunction in several IBS phenotypes, but additional studies are required to better clarify the underlying pathogenetic pathways. IBS heterogeneity could potentially be attributed to multiple causes that lead to different disease phenotypes, thus explaining the variability found between study results.

Commensal-innate immune miscommunication in IBD pathogenesis.

PubMed

Cario, Elke

2012-01-01

Commensal microbiota plays a key role in the health and disease of the host. The innate immune system comprises an essential functional component of the intestinal mucosal barrier, maintaining hyporesponsiveness to omnipresent harmless commensals in the lumen, but rapidly recognizing and combating invading bacteria through diverse antimicrobial mechanisms. Interactions between commensals and innate immune cells are constant, multidimensional and entirely context-dependent. Environment, genetics and host defense differentially modulate commensal-innate immune effects and functions in the intestinal mucosa. In IBD, dysbiosis, mucus layer disruption, impairment in bacterial clearance, intestinal epithelial cell barrier dysfunction and/or immune cell deregulation may lead to commensal-innate immune miscommunication, which critically drives mucosal inflammation and associated cancer. Copyright © 2012 S. Karger AG, Basel.

Therapeutic Role of Hematopoietic Stem Cells in Autism Spectrum Disorder-Related Inflammation

PubMed Central

Siniscalco, Dario; Bradstreet, James Jeffrey; Antonucci, Nicola

2013-01-01

Autism and autism spectrum disorders (ASDs) are heterogeneous, severe neuro-developmental disorders with core symptoms of dysfunctions in social interactions and communication skills, restricted interests, repetitive – stereotypic verbal and non-verbal behaviors. Biomolecular evidence points to complex gene-environmental interactions in ASDs. Several biochemical processes are associated with ASDs: oxidative stress (including endoplasmic reticulum stress), decreased methylation capacity, limited production of glutathione; mitochondrial dysfunction, intestinal dysbiosis, increased toxic metal burden, and various immune abnormalities. The known immunological disorders include: T-lymphocyte populations and function, gene expression changes in monocytes, several autoimmune-related findings, high levels of N-acetylgalactosaminidase (which precludes macrophage activation), and primary immune deficiencies. These immunological observations may result in minicolumn structural changes in the brain, as well as, abnormal immune mediation of synaptic functions. Equally, these immune dysregulations serve as the rationale for immune-directed interventions such as hematopoietic stem cells (HSCs), which are pivotal in controlling chronic inflammation and in the restoration of immunological balance. These properties make them intriguing potential agents for ASD treatments. This prospective review will focus on the current state-of-the-art knowledge and challenges intrinsic in the application of HSCs for ASD-related immunological disorders. PMID:23772227

21 Days head-down bed rest induces weakening of cell-mediated immunity - Some spaceflight findings confirmed in a ground-based analog.

PubMed

Kelsen, Jens; Bartels, Lars Erik; Dige, Anders; Hvas, Christian Lodberg; Frings-Meuthen, Petra; Boehme, Gisela; Thomsen, Marianne Kragh; Fenger-Grøn, Morten; Dahlerup, Jens Frederik

2012-08-01

Several studies indicate a weakening of cell-mediated immunity (CMI) and reactivation of latent herpes viruses during spaceflight. We tested the hypothesis that head-down bed rest (HDBR), a ground-based analog of spaceflight, mimics the impact of microgravity on human immunity. Seven healthy young males underwent two periods of 3 weeks HDBR in the test facility of the German Aerospace Center. As a nutritional countermeasure aimed against bone demineralisation, 90 mmol potassium bicarbonate (KHCO(3)) was administered daily in a crossover design. Blood samples were drawn on five occasions. Whole blood was stimulated with antigen i.e. Candida albicans, purified protein derivative (PPD) tuberculin, tetanus toxoid and Cytomegalovirus (CMV) (CMV-QuantiFERON). Flow cytometric analysis included CD4(+)CD25(+)CD127(-)FOXP3(+) regulatory T cells (Tregs), γδ T cells, B cells, NK cells and dendritic cells. In one of the two bed rest periods, we observed a significant decrease in production of interleukin-2 (IL-2), interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) following phytohemagglutinin (PHA) stimulation, with a rapid normalization being observed after HDBR. The cytokine levels showed a V-shaped pattern that led to a relativeTh2-shift in cytokine balance. Only three individuals responded to the specific T cell antigens without showing signs of an altered response during HDBR, nor did we observe reactivation of CMV or Epstein-Barr virus (EBV). Of unknown significance, dietary supplementation with KHCO(3) counteracted the decrease in IL-2 levels during HDBR, while there was no impact on other immunological parameters. We conclude that discrete alterations in CMI may be induced by HDBR in selected individuals. Copyright © 2012 Elsevier Ltd. All rights reserved.

Nerve growth factor and diarrhea-predominant irritable bowel syndrome (IBS-D): a potential therapeutic target?

PubMed

Xu, Xiao-juan; Liu, Liang; Yao, Shu-kun

2016-01-01

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder characterized by recurrent abdominal pain or discomfort associated with abnormal bowel habits. Diarrhea-predominant IBS (IBS-D) is a major subtype of IBS, the predominant manifestations of which are abdominal pain and diarrhea. The pathogenesis of IBS-D remained unknown until recently. The effects of psychosocial stress, central hypervigilance, neuroendocrine abnormality, disturbed gastrointestinal motility, mucosal immune activation, intestinal barrier dysfunction, visceral hypersensitivity (VH), altered gut flora, and genetic susceptibility may be involved in its development. Recently, increased attention has been placed on the neural-immune-endocrine network mechanism in IBS-D, especially the role of various neuroendocrine mediators. As a member of the neurotrophin family, nerve growth factor (NGF) has diverse biological effects, and participates in the pathogenesis of many diseases. Basic studies have demonstrated that NGF is associated with inflammatory- and stress-related VH, as well as stress-related intestinal barrier dysfunction. The aim of this study is to summarize recent literature and discuss the role of NGF in the pathophysiology of IBS-D, especially in VH and intestinal barrier dysfunction, as well as its potential as a therapeutic target in IBS-D.

Increased EBV Shedding in Astronaut Saliva During Spaceflight

NASA Technical Reports Server (NTRS)

Pierson, D. L.; Stowe, R. P.; Phillips, T.; Lugg, D. J.; Mehta, S. K.

2003-01-01

Shedding of Epstein-Barr virus (EBV) by astronauts before, during, and after space shuttle missions was quantified. Of 1398 saliva specimens from 32 astronauts, 314 (23%) were positive for EBV DNA by PCR analysis. Of the saliva specimens collected before flight, 29% were positive for EBV DNA and of those collected during or after flight, 16% were EBV-positive. The number of EBV DNA copies from samples taken during the flight was 417+/-31, significantly higher (P < 0.05) than the number of copies from the preflight (40+/-1.7) and postflight (44+/-5) phases. Eighteen control subjects shed EBV DNA with a frequency of 3.7% and a copy number of 40+/-2 per ml saliva. Ten days before flight and on landing day, antibody titers to EBV viral capsid antigen (VCA) were significantly (P < 0.05) higher than baseline levels. On landing day, urinary level of cortiso1 and catecholamines, and plasma levels of substance P and other neuropeptides, were increased over their preflight value. Results suggested that stress associated with spaceflight decreases cellular immunity and thereby leads to increased viral reactivation.

The Immune System in Obesity: Developing Paradigms Amidst Inconvenient Truths.

PubMed

Agrawal, Madhur; Kern, Philip A; Nikolajczyk, Barbara S

2017-08-15

Adipose tissue (AT) houses both innate and adaptive immune systems that are crucial for preserving AT function and metabolic homeostasis. In this review, we summarize recent information regarding progression of obesity-associated AT inflammation and insulin resistance. We additionally consider alterations in AT distribution and the immune system in males vs. females and among different racial populations. Innate and adaptive immune cell-derived inflammation drives insulin resistance both locally and systemically. However, new evidence also suggests that the immune system is equally vital for adipocyte differentiation and protection from ectopic lipid deposition. Furthermore, roles of anti-inflammatory immune cells such as regulatory T cells, "M2-like" macrophages, eosinophils, and mast cells are being explored, primarily due to promise of immunotherapeutic applications. Both immune responses and AT distribution are strongly influenced by factors like sex and race, which have been largely underappreciated in the field of metabolically-associated inflammation, or meta-flammation. More studies are required to recognize factors that switch inflammation from controlled to uncontrolled in obesity-associated pathogenesis and to integrate the combined effects of meta-flammation and immunometabolism. It is critical to recognize that the AT-associated immune system can be alternately beneficial and destructive; therefore, simply blocking immune responses early in obesity may not be the best clinical approach. The dearth of information on gender and race-associated disparities in metabolism, AT distribution, and the immune system suggest that a greater understanding of such differences will be critical to develop personalized treatments for obesity and the associated metabolic dysfunction.

Decreased Numbers of CD57+CD3- Cells Identify Potential Innate Immune Differences in Patients with Autism Spectrum Disorder.

PubMed

Siniscalco, Dario; Mijatovic, Tatjana; Bosmans, Eugene; Cirillo, Alessandra; Kruzliak, Peter; Lombardi, Vincent C; De Meirleir, Kenny; Antonucci, Nicola

2016-01-01

Autism spectrum disorders (ASD) are complex, and severe heterogeneous neurodevelopmental pathologies with accepted but complex immune system abnormalities. Additional knowledge regarding potential immune dysfunctions may provide a greater understanding of this malady. The aim of this study was to evaluate the CD57(+)CD3(-) mature lymphocyte subpopulation of natural killer cells as a marker of immune dysfunction in ASD. Three-color flow cytometry-based analysis of fresh peripheral blood samples from children with autism was utilized to measure CD57(+)CD3(-) lymphocytes. A reduction of CD57(+)CD3(-) lymphocyte count was recorded in a significant number of patients with autism. We demonstrated that the number of peripheral CD57(+)CD3(-) cells in children with autism often falls below the clinically accepted normal range. This implies that a defect in the counter-regulatory functions necessary for balancing pro-inflammatory cytokines exists, thus opening the way to chronic inflammatory conditions associated with ASD. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Immune Dysfunction as a Cause and Consequence of Malnutrition.

PubMed

Bourke, Claire D; Berkley, James A; Prendergast, Andrew J

2016-06-01

Malnutrition, which encompasses under- and overnutrition, is responsible for an enormous morbidity and mortality burden globally. Malnutrition results from disordered nutrient assimilation but is also characterized by recurrent infections and chronic inflammation, implying an underlying immune defect. Defects emerge before birth via modifications in the immunoepigenome of malnourished parents, and these may contribute to intergenerational cycles of malnutrition. This review summarizes key recent studies from experimental animals, in vitro models, and human cohorts, and proposes that immune dysfunction is both a cause and a consequence of malnutrition. Focusing on childhood undernutrition, we highlight gaps in current understanding of immune dysfunction in malnutrition, with a view to therapeutically targeting immune pathways as a novel means to reduce morbidity and mortality. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Peripheral administration of the soluble TNF inhibitor XPro1595 modifies brain immune cell profiles, decreases beta-amyloid plaque load, and rescues impaired long-term potentiation in 5xFAD mice.

PubMed

MacPherson, Kathryn P; Sompol, Pradoldej; Kannarkat, George T; Chang, Jianjun; Sniffen, Lindsey; Wildner, Mary E; Norris, Christopher M; Tansey, Malú G

2017-06-01

Clinical and animal model studies have implicated inflammation and peripheral immune cell responses in the pathophysiology of Alzheimer's disease (AD). Peripheral immune cells including T cells circulate in the cerebrospinal fluid (CSF) of healthy adults and are found in the brains of AD patients and AD rodent models. Blocking entry of peripheral macrophages into the CNS was reported to increase amyloid burden in an AD mouse model. To assess inflammation in the 5xFAD (Tg) mouse model, we first quantified central and immune cell profiles in the deep cervical lymph nodes and spleen. In the brains of Tg mice, activated (MHCII + , CD45 high , and Ly6C high ) myeloid-derived CD11b + immune cells are decreased while CD3 + T cells are increased as a function of age relative to non-Tg mice. These immunological changes along with evidence of increased mRNA levels for several cytokines suggest that immune regulation and trafficking patterns are altered in Tg mice. Levels of soluble Tumor Necrosis Factor (sTNF) modulate blood-brain barrier (BBB) permeability and are increased in CSF and brain parenchyma post-mortem in AD subjects and Tg mice. We report here that in vivo peripheral administration of XPro1595, a novel biologic that sequesters sTNF into inactive heterotrimers, reduced the age-dependent increase in activated immune cells in Tg mice, while decreasing the overall number of CD4 + T cells. In addition, XPro1595 treatment in vivo rescued impaired long-term potentiation (LTP) measured in brain slices in association with decreased Aβ plaques in the subiculum. Selective targeting of sTNF may modulate brain immune cell infiltration, and prevent or delay neuronal dysfunction in AD. Immune cells and cytokines perform specialized functions inside and outside the brain to maintain optimal brain health; but the extent to which their activities change in response to neuronal dysfunction and degeneration is not well understood. Our findings indicate that neutralization of sTNF reduced the age-dependent increase in activated immune cells in Tg mice, while decreasing the overall number of CD4 + T cells. In addition, impaired long-term potentiation (LTP) was rescued by XPro1595 in association with decreased hippocampal Aβ plaques. Selective targeting of sTNF holds translational potential to modulate brain immune cell infiltration, dampen neuroinflammation, and prevent or delay neuronal dysfunction in AD. Copyright © 2017 Elsevier Inc. All rights reserved.

Risk of Adverse Health Effects Due to Host-Microorganism Interactions

NASA Technical Reports Server (NTRS)

Ott, C. Mark; Oubre, Cherie; Wallace, Sarah; Mehta, Satish; Pierson, Duane

2016-01-01

Numerous spaceflight experiments have been conducted to investigate alterations in microbial responses resulting from culture during spaceflight and spaceflight-analogs. However, recent studies investigating spaceflight-associated alterations in microbial virulence have initiated the review and production of evidence to better understand the impact these alterations would have on the incidence of infectious disease during a spaceflight exploration mission. The preponderance of evidence indicates that alterations in microbial gene expression and phenotype (including virulence) are occurring; however, the clinical implications of such changes are still unclear. Greater knowledge is required including a better understanding of the mechanism behind unique spaceflight-associated microbial responses to determine how this environmental stimulus impacts various microorganisms, their diversity and concentration in the spacecraft and crew microbiome, their impact on the vehicle and crew, and their resistance to current mitigation and antibiotic regimens. This knowledge will enable us to determine requirements, guidelines, and processes for design and monitoring of the next generation vehicles.

Blocking type I interferon signaling enhances T cell recovery and reduces HIV-1 reservoirs.

PubMed

Cheng, Liang; Ma, Jianping; Li, Jingyun; Li, Dan; Li, Guangming; Li, Feng; Zhang, Qing; Yu, Haisheng; Yasui, Fumihiko; Ye, Chaobaihui; Tsao, Li-Chung; Hu, Zhiyuan; Su, Lishan; Zhang, Liguo

2017-01-03

Despite the efficient suppression of HIV-1 replication that can be achieved with combined antiretroviral therapy (cART), low levels of type I interferon (IFN-I) signaling persist in some individuals. This sustained signaling may impede immune recovery and foster viral persistence. Here we report studies using a monoclonal antibody to block IFN-α/β receptor (IFNAR) signaling in humanized mice (hu-mice) that were persistently infected with HIV-1. We discovered that effective cART restored the number of human immune cells in HIV-1-infected hu-mice but did not rescue their immune hyperactivation and dysfunction. IFNAR blockade fully reversed HIV-1-induced immune hyperactivation and rescued anti-HIV-1 immune responses in T cells from HIV-1-infected hu-mice. Finally, we found that IFNAR blockade in the presence of cART reduced the size of HIV-1 reservoirs in lymphoid tissues and delayed HIV-1 rebound after cART cessation in the HIV-1-infected hu-mice. We conclude that low levels of IFN-I signaling contribute to HIV-1-associated immune dysfunction and foster HIV-1 persistence in cART-treated hosts. Our results suggest that blocking IFNAR may provide a potential strategy to enhance immune recovery and reduce HIV-1 reservoirs in individuals with sustained elevations in IFN-I signaling during suppressive cART.

Incidence of Latent Virus Shedding during Space Flight

NASA Technical Reports Server (NTRS)

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

2008-01-01

Measurements of immune parameters of both cellular and innate immunity indicate alterations in immune function in astronauts. Immune changes are due to stress and perhaps other factors associated with launch, flight, and landing phases. Medical relevance of observed changes is not known. The reactivation of latent viruses has been identified as an important in vivo indicator of clinically relevant immune changes. The polymerase chain reaction (PCR) was used to detect the presence of specific viral DNA in body fluids. Initial studies demonstrated Epstein-Barr virus (EBV) reactivation during all 3 mission phases. EBV is shed in saliva following reactivation from B-cells. Incidence of EBV in saliva was higher than control subjects during all 3 mission phases. However, quantitative PCR revealed 10-fold higher levels of EBV DNA present in saliva collected during flight than found in pre- and post flight specimens. To determine if other latent viruses showed similar effects, cytomegalovirus (CMV), another herpes virus, shed in urine following reactivation was studied. A very low incidence (less than 2%) of CMV in urine is found in healthy, lowstressed individuals. However, 25-50% of astronauts shed CMV in their urine before, during, or after flight. Our studies are now focused on varicella-zoster virus (VZV), the etiological agent of chicken-pox during childhood and shingles later in life. We demonstrated reactivation of VZV and shedding of the virus during and after spaceflight in saliva of astronauts with no sign of active infection or symptoms. The maximum shedding of VZV occurred during the flight phase and diminishes rapidly during the first five days after landing. We have utilized the same PCR assay for VZV in a clinical study of shingles patients. Generally, shingles patients shed much more VZV in saliva than astronauts. However, the VZV levels in astronauts overlap with the lower range of VZV numbers in shingles patients. Saliva from shingles patients and astronauts were cultured and infectious VZV was recovered from both groups. We have concluded that multiple latent viruses do reactivate before, during, and after spaceflight and serve as very sensitive indicators for diminished cellular immunity. Future plans will be focused on the clinical risks posed by the reactivation of these viruses. Initial efforts will determine the effect of longer missions on the International Space Station on the reactivation patterns of these viruses.

Effect Of Spaceflight On Microbial Gene Expression And Virulence: Preliminary Results From Microbe Payload Flown On-Board STS-115

NASA Technical Reports Server (NTRS)

Wilson, J. W.; HonerzuBentrup, K,; Schurr, M. J.; Buchanan, K.; Morici, L.; Hammond, T.; Allen, P.; Baker, C.; Ott, C. M.; Nelman-Gonzalez M.;

Oxidative Stress in HIV Infection and Alcohol Use: Role of Redox Signals in Modulation of Lipid Rafts and ATP-Binding Cassette Transporters.

PubMed

Thangavel, Samikkannu; Mulet, Carmen T; Atluri, Venkata S R; Agudelo, Marisela; Rosenberg, Rhonda; Devieux, Jessy G; Nair, Madhavan P N

2018-02-01

Human immunodeficiency virus (HIV) infection induces oxidative stress and alcohol use accelerates disease progression, subsequently causing immune dysfunction. However, HIV and alcohol impact on lipid rafts-mediated immune dysfunction remains unknown. In this study, we investigate the modulation by which oxidative stress induces reactive oxygen species (ROS) affecting redox expression, lipid rafts caveiloin-1, ATP-binding cassette (ABC) transporters, and transcriptional sterol regulatory element-binding protein (SREBP) gene and protein modification and how these mechanisms are associated with arachidonic acid (AA) metabolites in HIV positive alcohol users, and how they escalate immune dysfunction. In both alcohol using HIV-positive human subjects and in vitro studies of alcohol with HIV-1 gp120 protein in peripheral blood mononuclear cells, increased ROS production significantly affected redox expression in glutathione synthetase (GSS), super oxide dismutase (SOD), and glutathione peroxidase (GPx), and subsequently impacted lipid rafts Cav-1, ABC transporters ABCA1, ABCG1, ABCB1, and ABCG4, and SREBP transcription. The increased level of rate-limiting enzyme 3-hydroxy-3-methylglutaryl HMG-CoA reductase (HMGCR), subsequently, inhibited 7-dehydrocholesterol reductase (DHCR-7). Moreover, the expression of cyclooxygenase-2 (COX-2) and lipoxygenase-5 (5-LOX) mRNA and protein modification tentatively increased the levels of prostaglandin E2 synthases (PGE 2 ) in plasma when compared with either HIV or alcohol alone. This article suggests for the first time that the redox inhibition affects lipid rafts, ABC-transporter, and SREBP transcription and modulates AA metabolites, serving as an important intermediate signaling network during immune cell dysfunction in HIV-positive alcohol users. These findings indicate that HIV infection induces oxidative stress and redox inhibition, affecting lipid rafts and ABC transports, subsequently upregulating AA metabolites and leading to immune toxicity, and further exacerbation with alcohol use. Antioxid. Redox Signal. 28, 324-337.

Altered Immune Function Associated with Disordered Neural Connectivity and Executive Dysfunctions: A Neurophysiological Study on Children with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Han, Yvonne M. Y.; Chan, Agnes S.; Sze, Sophia L.; Cheung, Mei-Chun; Wong, Chun-kwok; Lam, Joseph M. K.; Poon, Priscilla M. K.

2013-01-01

Previous studies have shown that children with autism spectrum disorders (ASDs) have impaired executive function, disordered neural connectivity, and abnormal immunologic function. The present study examined whether these abnormalities were associated. Seventeen high-functioning (HFA) and 17 low-functioning (LFA) children with ASD, aged 8-17…

Stress-induced reactivation of Epstein-Barr virus in astronauts

NASA Technical Reports Server (NTRS)

Stowe, R. P.; Pierson, D. L.; Feeback, D. L.; Barrett, A. D.

2000-01-01

Herpesviruses are leading causes of infectious blindness and death in immunocompromised individuals. Impaired cellular immunity, which is known to result in increased frequency and severity of herpesvirus infections, has been demonstrated both during and after spaceflight. Therefore, we examined whether Epstein-Barr virus (EBV), a well-characterized latent herpesvirus, undergoes reactivation in astronauts. Sera from Shuttle astronauts, taken before and after spaceflight, were examined for evidence of EBV reactivation. The geometric mean antibody titer to EBV viral capsid antigen (VCA) was significantly increased prior to flight compared to baseline (p = 0. 0001). After spaceflight, evidence of acute lytic replication was found in which 8- to 64-fold increases in EBV early antigen (EA) antibodies occurred without significant increases in antibodies to measles virus. Additionally, stress-induced shifts in circulating leukocytes and elevated levels of urinary cortisol and epinephrine were found. Overall, significant increases in EA or high VCA/EA antibody titers were found in 8 of 23 (35%) male astronauts and 3 of 5 (60%) female astronauts. These results indicate that stress reactivates EBV prior to flight and suggest that acute lytic replication of EBV occurs during spaceflight. Copyright 2000 S. Karger AG, Basel.

Peripheral leukocyte subpopulations and catecholamine levels in astronauts as a function of mission duration

NASA Technical Reports Server (NTRS)

Mills, P. J.; Meck, J. V.; Waters, W. W.; D'Aunno, D.; Ziegler, M. G.

2001-01-01

OBJECTIVE: The objective of this study was to determine the effects of spaceflight duration on immune cells and their relationship to catecholamine levels. METHODS: Eleven astronauts who flew aboard five different US Space Shuttle flights ranging in duration from 4 to 16 days were studied before launch and after landing. RESULTS: Consistent with prior studies, spaceflight was associated with a significant increase in the number of circulating white blood cells (p <.01), including neutrophils (p <.01), monocytes (p <.05), CD3+CD4+ T-helper cells (p <.05), and CD19+ B cells (p <.01). In contrast, the number of CD3-CD16+56+ natural killer cells was decreased (p <.01). Plasma norepinephrine levels were increased at landing (p <.01) and were significantly correlated with the number of white blood cells (p <.01), neutrophils (p <.01), monocytes (p <.01), and B cells (p <.01). Astronauts who were in space for approximately 1 week showed a significantly larger increase on landing in plasma norepinephrine (p =.02) and epinephrine (p =.03) levels, as well as number of circulating CD3+CD4+ T-helper cells (p <.05) and CD3+CD8+ T-cytotoxic cells (p <.05) as compared with astronauts in space for approximately 2 weeks. CONCLUSIONS: The data suggest that the stress of spaceflight and landing may lead to a sympathetic nervous system-mediated redistribution of circulating leukocytes, an effect potentially attenuated after longer missions.

Monitoring Immune System Function and Reactivation of Latent Viruses in the Artificial Gravity Pilot Study

NASA Technical Reports Server (NTRS)

Mehta, Satish K.; Crucian, Brian; Pierson, Duane L.; Sams, Clarence; Stowe, Raymond P.

2007-01-01

Numerous studies have indicated that dysregulation of the immune system occurs during or after spaceflight. Using 21 day -6 degrees head-down tilt bed rest as a spaceflight analog, this study describes the effects of artificial gravity (AG) as a daily countermeasure on immunity, stress and reactivation of clinically important latent herpes viruses. The specific aims were to evaluate psychological and physiological stress, to determine the status of the immune system, and to quantify reactivation of latent herpes viruses. Blood, saliva, and urine samples were collected from each participating subject at different times throughout the study. An immune assessment was performed on all treatment and control subjects that consisted of a comprehensive peripheral immunophenotype analysis, intracellular cytokine profiles and a measurement of T cell function. The treatment group displayed no differences throughout the course of the study with regards to peripheral leukocyte distribution, cytokine production or T cell function. Shedding of Epstein barr virus (EBV), Cytomegalovirus (CMV), and Varicella zoster virus (VZV) was quantified by real time PCR in saliva and urine samples, respectively. There was no significant difference in CMV DNA in the treatment group as compared to the control group. EBV and VZV on the other hand showed a mild reactivation during the study. There were no significant differences in cortisol between the control and treatment groups. In addition, no significant differences between antiviral antibody titers (EBV-VCA, -EA, -EBNA, CMV) or tetramer-positive (EBV, CMV) were found between the two groups. EBV DNA copies in blood were typically undetectable but never exceeded 1,500 copies per 106 PBMCs. Overall, these data indicate that the artificial gravity countermeasure and the 21 day head-down tilt bed rest regimen had no observable adverse effect on immune function.

Monitoring Immune System Function and Reactivation of Latent Viruses in the Artificial Gravity Pilot Study

NASA Technical Reports Server (NTRS)

Mehta, Satish; Crusian, Brian; Pierson, Duane; Sams, Clarence; Stowe, Raymond

2007-01-01

Numerous studies have indicated that dysregulation of the immune system occurs during or after spaceflight. Using 21 day -6 deg. head-down tilt bed rest as a spaceflight analog, this study describes the effects of artificial gravity as a daily countermeasure on immunity, stress and reactivation of clinically important latent herpes viruses. The specific aims were to evaluate psychological and physiological stress, to determine the status of the immune system and to quantify reactivation of latent herpes viruses. Blood, saliva, and urine samples were collected from each participating subject at different times throughout the study. An immune assessment was performed on all treatment and control subjects that consisted of a comprehensive peripheral immunophenotype analysis, intracellular cytokine profiles and a measurement of T cell function. The treatment group displayed no differences throughout the course of the study with regards to peripheral leukocyte distribution, cytokine production or T cell function. Shedding of EBV and CMV was quantified by real time PCR in saliva and urine samples, respectively. There was no significant difference in CMV DNA in the treatment group as compared to the control group. EBV and VZV on the other hand showed a mild reactivation during the study. There were no significant differences in plasma cortisol between the control and treatment groups. In addition, no significant differences between antiviral antibody titers (EBV-VCA, -EA, -EBNA, CMV) or tetramer-positive (EBV, CMV) were found between the two groups. EBV DNA copies in blood were typically undetectable but never exceeded 1,500 copies per 10(exp 6) PBMCs. These data indicate that the artificial gravity countermeasure and the 21 day head-down tilt bed rest regimen had no observable adverse effect on immune function.

IFN-α and CD46 stimulation are associated with active lupus and skew natural T regulatory cell differentiation to type 1 regulatory T (Tr1) cells

PubMed Central

Le Buanec, Hélène; Gougeon, Marie-Lise; Mathian, Alexis; Lebon, Pierre; Dupont, Jean-Michel; Peltre, Gabriel; Hemon, Patrice; Schmid, Michel; Bizzini, Bernard; Künding, Thomas; Burny, Arsène; Bensussan, Armand; Amoura, Zahir; Gallo, Robert C.; Zagury, Daniel

2011-01-01

Immune suppressive activities exerted by regulatory T-cell subsets have several specific functions, including self-tolerance and regulation of adaptive immune reactions, and their dysfunction can lead to autoimmune diseases and contribute to AIDS and cancer. Two functionally distinct regulatory T-cell subsets are currently identified in peripheral tissues: thymus-developed natural T regulatory cells (nTregs) controlling self-tolerance and antiinflammatory IL-10–secreting type 1 regulatory T cells (Tr1) derived from Ag-stimulated T cells, which regulate inflammation-dependent adaptive immunity and minimize immunopathology. We establish herein that cell contact-mediated nTreg regulatory function is inhibited by inflammation, especially in the presence of the complement C3b receptor (CD46). Instead, as with other T-cell subsets, the latter inflammatory conditions of stimulation skew nTreg differentiation to Tr1 cells secreting IL-10, an effect potentiated by IFN-α. The clinical relevance of these findings was verified in a study of 152 lupus patients, in which we showed that lupus nTreg dysfunction is not due to intrinsic defects but is rather induced by C3b stimulation of CD46 and IFN-α and that these immune components of inflammation are directly associated with active lupus. These results provide a rationale for using anti–IFN-α Ab immunotherapy in lupus patients. PMID:22065791

Innate immune reconstitution with suppression of HIV-1.

PubMed

Scully, Eileen P; Lockhart, Ainsley; Garcia-Beltran, Wilfredo; Palmer, Christine D; Musante, Chelsey; Rosenberg, Eric; Allen, Todd M; Chang, J Judy; Bosch, Ronald J; Altfeld, Marcus

2016-03-17

Progressive HIV-1 infection leads to both profound immune suppression and pathologic inflammation in the majority of infected individuals. While adaptive immune dysfunction, as evidenced by CD4 + T cell depletion and exhaustion, has been extensively studied, less is known about the functional capacity of innate immune cell populations in the context of HIV-1 infection. Given the broad susceptibility to opportunistic infections and the dysregulated inflammation observed in progressive disease, we hypothesized that there would be significant changes in the innate cellular responses. Using a cohort of patients with multiple samplings before and after antiretroviral therapy (ART) initiation, we demonstrated increased responses to innate immune stimuli following viral suppression, as measured by the production of inflammatory cytokines. Plasma viral load itself had the strongest association with this change in innate functional capacity. We further identified epigenetic modifications in the TNFA promoter locus in monocytes that are associated with viremia, suggesting a molecular mechanism for the observed changes in innate immune function following initiation of ART. These data indicate that suppression of HIV-1 viremia is associated with changes in innate cellular function that may in part determine the restoration of protective immune responses.

Innate immune reconstitution with suppression of HIV-1

PubMed Central

Scully, Eileen P.; Garcia-Beltran, Wilfredo; Palmer, Christine D.; Musante, Chelsey; Rosenberg, Eric; Allen, Todd M.; Bosch, Ronald J.

2016-01-01

Progressive HIV-1 infection leads to both profound immune suppression and pathologic inflammation in the majority of infected individuals. While adaptive immune dysfunction, as evidenced by CD4+ T cell depletion and exhaustion, has been extensively studied, less is known about the functional capacity of innate immune cell populations in the context of HIV-1 infection. Given the broad susceptibility to opportunistic infections and the dysregulated inflammation observed in progressive disease, we hypothesized that there would be significant changes in the innate cellular responses. Using a cohort of patients with multiple samplings before and after antiretroviral therapy (ART) initiation, we demonstrated increased responses to innate immune stimuli following viral suppression, as measured by the production of inflammatory cytokines. Plasma viral load itself had the strongest association with this change in innate functional capacity. We further identified epigenetic modifications in the TNFA promoter locus in monocytes that are associated with viremia, suggesting a molecular mechanism for the observed changes in innate immune function following initiation of ART. These data indicate that suppression of HIV-1 viremia is associated with changes in innate cellular function that may in part determine the restoration of protective immune responses. PMID:27158667

Brain Activations for Vestibular Stimulation and Dual Tasking Change with Spaceflight

NASA Technical Reports Server (NTRS)

Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia; De Dios, Yiri; Gadd, Nichole; Wood, Scott; Riascos, Roy; Kofman, Igor; Bloomberg, Jacob; Mulavara, Ajitkumar;

Current insights into the innate immune system dysfunction in irritable bowel syndrome

PubMed Central

Lazaridis, Nikolaos; Germanidis, Georgios

2018-01-01

Irritable bowel syndrome (IBS) is a functional bowel disorder associated with abdominal pain and alterations in bowel habits. The presence of IBS greatly impairs patients’ quality of life and imposes a high economic burden on the community; thus, there is intense pressure to reveal its elusive pathogenesis. Many etiological mechanisms have been implicated, but the pathophysiology of the syndrome remains unclear. As a result, novel drug development has been slow and no pharmacological intervention is universally accepted. A growing evidence implicates the role of low-grade inflammation and innate immune system dysfunction, although contradictory results have frequently been presented. Mast cells (MC), eosinophils and other key immune cells together with their mediators seem to play an important role, at least in subgroups of IBS patients. Cytokine imbalance in the systematic circulation and in the intestinal mucosa may also characterize IBS presentation. Toll-like receptors and their emerging role in pathogen recognition have also been highlighted recently, as dysregulation has been reported to occur in patients with IBS. This review summarizes the current knowledge regarding the involvement of any immunological alteration in the development of IBS. There is substantial evidence to support innate immune system dysfunction in several IBS phenotypes, but additional studies are required to better clarify the underlying pathogenetic pathways. IBS heterogeneity could potentially be attributed to multiple causes that lead to different disease phenotypes, thus explaining the variability found between study results. PMID:29507464

Protection from JP-8 jet fuel induced immunotoxicity by administration of aerosolized substance P.

PubMed

Harris, D T; Sakiestewa, D; Robledo, R F; Witten, M

1997-01-01

Chronic exposure to jet fuel has been shown to cause human liver dysfunction, emotional dysfunction, abnormal electroencephalograms, shortened attention spans, and decreased sensorimotor speed. The United States Air Force has decided to implement the widespread use of JP-8 jet fuel in its operations, although a thorough understanding of its potential effects upon exposed personnel is unclear. Exposure to potential environment toxicants such as JP-8 may have significant effects on host physiology. Previous studies in mice have shown that short-term, low concentration JP-8 exposure had significant effects on the immune system; e.g., decreased viable immune cell numbers, decreased immune organ weights, and loss on immune function that persisted for extended periods of time (i.e., up to 4 weeks post-exposure). Previous studies have shown that JP-8 induced pulmonary dysfunction was associated with a decrease in levels of the neuropeptide substance P (SP) in lung lavage fluids. It was found that administration of aerosolized SP was able to protect exposed animals from such JP-8 induced pulmonary changes. In the current study, aerosolized SP was analyzed for its effects on JP-i induced immunotoxicity in exposed mice. It was observed that SP administration could protect JP-8 exposed animals from losses of viable immune cell numbers, but not losses in immune organ weights. Further, exposure of animals to SP inhibitors generally increased the immunotoxicity of JP-8 exposure. SP appeared to act on all immune cell populations equally as analyzed by flow cytometry, as no one immune cell population appeared to be preferentially protected by SP. Also, SP administration was capable of protecting JP-8 exposed animals from loss of immune function at all concentrations of JP-8 utilized (250-2500 mg/m3). Significantly, SP only needed to be administered for 15 minutes after JP-8 exposure, and was active at both 1 microM and 1 nM concentrations. Thus, SP administration appears to be a relatively simple and efficient means to reverse the immunotoxicity due to hydrocarbon exposure.

Human Immune Function and Microbial Pathogenesis in Human Spaceflight

NASA Technical Reports Server (NTRS)

Pierson, Duane J.; Ott, M.

2006-01-01

This oral presentation was requested by Conference conveners. The requested subject is microbial risk assessment considering changes in the human immune system during flight and microbial diversity of environmental samples aboard the International Space Station (ISS). The presentation will begin with an introduction discussing the goals and limitations of microbial risk assessment during flight. The main portion of the presentation will include changes in the immune system that have been published, historical data from microbial analyses, and initial modeling of the environmental flora aboard ISS. The presentation will conclude with future goals and techniques to enhance our ability to perform microbial risk assessment on long duration missions.

Immunological findings in autism.

PubMed

Cohly, Hari Har Parshad; Panja, Asit

2005-01-01

The immunopathogenesis of autism is presented schematically in Fig. 1. Two main immune dysfunctions in autism are immune regulation involving pro-inflammatory cytokines and autoimmunity. Mercury and an infectious agent like the measles virus are currently two main candidate environmental triggers for immune dysfunction in autism. Genetically immune dysfunction in autism involves the MHC region, as this is an immunologic gene cluster whose gene products are Class I, II, and III molecules. Class I and II molecules are associated with antigen presentation. The antigen in virus infection initiated by the virus particle itself while the cytokine production and inflammatory mediators are due to the response to the putative antigen in question. The cell-mediated immunity is impaired as evidenced by low numbers of CD4 cells and a concomitant T-cell polarity with an imbalance of Th1/Th2 subsets toward Th2. Impaired humoral immunity on the other hand is evidenced by decreased IgA causing poor gut protection. Studies showing elevated brain specific antibodies in autism support an autoimmune mechanism. Viruses may initiate the process but the subsequent activation of cytokines is the damaging factor associated with autism. Virus specific antibodies associated with measles virus have been demonstrated in autistic subjects. Environmental exposure to mercury is believed to harm human health possibly through modulation of immune homeostasis. A mercury link with the immune system has been postulated due to the involvement of postnatal exposure to thimerosal, a preservative added in the MMR vaccines. The occupational hazard exposure to mercury causes edema in astrocytes and, at the molecular level, the CD95/Fas apoptotic signaling pathway is disrupted by Hg2+. Inflammatory mediators in autism usually involve activation of astrocytes and microglial cells. Proinflammatory chemokines (MCP-1 and TARC), and an anti-inflammatory and modulatory cytokine, TGF-beta1, are consistently elevated in autistic brains. In measles virus infection, it has been postulated that there is immune suppression by inhibiting T-cell proliferation and maturation and downregulation MHC class II expression. Cytokine alteration of TNF-alpha is increased in autistic populations. Toll-like-receptors are also involved in autistic development. High NO levels are associated with autism. Maternal antibodies may trigger autism as a mechanism of autoimmunity. MMR vaccination may increase risk for autism via an autoimmune mechanism in autism. MMR antibodies are significantly higher in autistic children as compared to normal children, supporting a role of MMR in autism. Autoantibodies (IgG isotype) to neuron-axon filament protein (NAFP) and glial fibrillary acidic protein (GFAP) are significantly increased in autistic patients (Singh et al., 1997). Increase in Th2 may explain the increased autoimmunity, such as the findings of antibodies to MBP and neuronal axonal filaments in the brain. There is further evidence that there are other participants in the autoimmune phenomenon. (Kozlovskaia et al., 2000). The possibility of its involvement in autism cannot be ruled out. Further investigations at immunological, cellular, molecular, and genetic levels will allow researchers to continue to unravel the immunopathogenic mechanisms' associated with autistic processes in the developing brain. This may open up new avenues for prevention and/or cure of this devastating neurodevelopmental disorder.

Suborbital commercial spaceflight crewmember medical issues.

PubMed

2011-04-01

As directed by the Council of the Aerospace Medical Association, the Commercial Spaceflight Working Group has developed the following position paper concerning medical issues for commercial suborbital spaceflight crewmembers. This position paper has been approved by the AsMA Council to become a policy of the AsMA.

Effect of Low Shear Modeled Microgravity (LSMMG) on the Probiotic Lactobacillus Acidophilus ATCC 4356

NASA Technical Reports Server (NTRS)

Stahl, S.; Voorhies, A.; Lorenzi, H.; Castro-Wallace, S.; Douglas, G.

2016-01-01

The introduction of generally recognized as safe (GRAS) probiotic microbes into the spaceflight food system has the potential for use as a safe, non-invasive, daily countermeasure to crew microbiome and immune dysregulation. However, the microgravity effects on the stress tolerances and genetic expression of probiotic bacteria must be determined to confirm translation of strain benefits and to identify potential for optimization of growth, survival, and strain selection for spaceflight. The work presented here demonstrates the translation of characteristics of a GRAS probiotic bacteria to a microgravity analog environment. Lactobacillus acidophilus ATCC 4356 was grown in the low shear modeled microgravity (LSMMG) orientation and the control orientation in the rotating wall vessel (RWV) to determine the effect of LSMMG on the growth, survival through stress challenge, and gene expression of the strain. No differences were observed between the LSMMG and control grown L. acidophilus, suggesting that the strain will behave similarly in spaceflight and may be expected to confer Earth-based benefits.

Defining immunological dysfunction in sepsis: A requisite tool for precision medicine.

PubMed

Bermejo-Martin, Jesús F; Andaluz-Ojeda, David; Almansa, Raquel; Gandía, Francisco; Gómez-Herreras, Jose Ignacio; Gomez-Sanchez, Esther; Heredia-Rodríguez, María; Eiros, Jose Maria; Kelvin, David J; Tamayo, Eduardo

2016-05-01

Immunological dysregulation is now recognised as a major pathogenic event in sepsis. Stimulation of immune response and immuno-modulation are emerging approaches for the treatment of this disease. Defining the underlying immunological alterations in sepsis is important for the design of future therapies with immuno-modulatory drugs. Clinical studies evaluating the immunological response in adult patients with Sepsis and published in PubMed were reviewed to identify features of immunological dysfunction. For this study we used key words related with innate and adaptive immunity. Ten major features of immunological dysfunction (FID) were identified involving quantitative and qualitative alterations of [antigen presentation](FID1), [T and B lymphocytes] (FID2), [natural killer cells] (FID3), [relative increase in T regulatory cells] (FID4), [increased expression of PD-1 and PD-ligand1](FID5), [low levels of immunoglobulins](FID6), [low circulating counts of neutrophils and/or increased immature forms in non survivors](FID7), [hyper-cytokinemia] (FID8), [complement consumption] (FID9), [defective bacterial killing by neutrophil extracellular traps](FID10). This review article identified ten major features associated with immunosuppression and immunological dysregulation in sepsis. Assessment of these features could help in utilizing precision medicine for the treatment of sepsis with immuno-modulatory drugs. Copyright © 2016 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Modified Mediterranean Diet for Enrichment of Short Chain Fatty Acids: Potential Adjunctive Therapeutic to Target Immune and Metabolic Dysfunction in Schizophrenia?

PubMed Central

Joseph, Jamie; Depp, Colin; Shih, Pei-an B.; Cadenhead, Kristen S.; Schmid-Schönbein, Geert

2017-01-01

Growing interest in gut and digestive processes and their potential link to brain and peripheral based inflammation or biobehavioral phenotypes has led to an increasing number of basic and translational scientific reports focused on the role of gut microbiota within the context of neuropsychiatric disorders. However, the effect of dietary modification on specific gut metabolites, in association with immune, metabolic, and psychopathological functioning in schizophrenia spectrum disorders has not been well characterized. The short chain fatty acids (SCFA) acetate, butyrate, and propionate, major metabolites derived from fermentation of dietary fibers by gut microbes, interact with multiple immune and metabolic pathways. The specific pathways that SCFA are thought to target, are dysregulated in cardiovascular disease, type II diabetes, and systemic inflammation. Most notably, these disorders are consistently linked to an attenuated lifespan in schizophrenia. Although, unhealthy dietary intake patterns and increased prevalence of immune and metabolic dysfunction has been observed in people with schizophrenia; dietary interventions have not been well utilized to target immune or metabolic illness. Prior schizophrenia patient trials primarily focused on the effects of gluten free diets. Findings from these studies indicate that a diet avoiding gluten benefits a limited subset of patients, individuals with celiac disease or non-celiac gluten sensitivity. Therefore, alternative dietary and nutritional modifications such as high-fiber, Mediterranean style, diets that enrich the production of SCFA, while being associated with a minimal likelihood of adverse events, may improve immune and cardiovascular outcomes linked to premature mortality in schizophrenia. With a growing literature demonstrating that SCFA can cross the blood brain barrier and target key inflammatory and metabolic pathways, this article highlights enriching dietary intake for SCFA as a potential adjunctive therapy for people with schizophrenia. PMID:28396623

Physiological adaptations and countermeasures associated with long-duration spaceflights.

PubMed

Tipton, C M; Hargens, A

1996-08-01

Since 1961, there have been more than 165 flights involving several hundred individuals who have remained in a space environment from 15 min to more than a year. In addition, plans exist for humans to explore, colonize, and remain in microgravity for 1000 d or more. This symposium will address the current state of knowledge in select aspects associated with the cardiovascular, fluid and electrolytes, musculoskeletal, and the neuroendocrine and immune systems. The authors will focus on responses, mechanisms, and the appropriate countermeasures to minimize or prevent the physiological and biochemical consequences of a microgravity environment. Since exercise is frequently cited as a generic countermeasure, this topic will be covered in greater detail. Models for simulated microgravity conditions will be discussed in subsequent manuscripts, as will future directions for ground-based research.

Physiological adaptations and countermeasures associated with long-duration spaceflights

NASA Technical Reports Server (NTRS)

Tipton, C. M.; Hargens, A.

1996-01-01

Since 1961, there have been more than 165 flights involving several hundred individuals who have remained in a space environment from 15 min to more than a year. In addition, plans exist for humans to explore, colonize, and remain in microgravity for 1000 d or more. This symposium will address the current state of knowledge in select aspects associated with the cardiovascular, fluid and electrolytes, musculoskeletal, and the neuroendocrine and immune systems. The authors will focus on responses, mechanisms, and the appropriate countermeasures to minimize or prevent the physiological and biochemical consequences of a microgravity environment. Since exercise is frequently cited as a generic countermeasure, this topic will be covered in greater detail. Models for simulated microgravity conditions will be discussed in subsequent manuscripts, as will future directions for ground-based research.

DNA methylation and inflammation marker profiles associated with a history of depression.

PubMed

Crawford, Bethany; Craig, Zoe; Mansell, Georgina; White, Isobel; Smith, Adam; Spaull, Steve; Imm, Jennifer; Hannon, Eilis; Wood, Andrew; Yaghootkar, Hanieh; Ji, Yingjie; Mullins, Niamh; Lewis, Cathryn M; Mill, Jonathan; Murphy, Therese M

2018-05-22

Depression is a common and disabling disorder, representing a major social and economic health issue. Moreover, depression is associated with the progression of diseases with an inflammatory etiology including many inflammatory-related disorders. At the molecular level, the mechanisms by which depression might promote the onset of these diseases and associated immune-dysfunction are not well understood. In this study we assessed genome-wide patterns of DNA methylation in whole blood-derived DNA obtained from individuals with a self-reported history of depression (n = 100) and individuals without a history of depression (n = 100) using the Illumina 450K microarray. Our analysis identified 6 significant (Sidak corrected P < 0.05) depression-associated differentially methylated regions (DMRs); the top-ranked DMR was located in exon 1 of the LTB4R2 gene (Sidak corrected P = 1.27 x 10-14). Polygenic risk scores (PRS) for depression were generated and known biological markers of inflammation, telomere length (TL) and IL-6, were measured in DNA and serum samples respectively. Next, we employed a systems-level approach to identify networks of co-methylated loci associated with a history of depression, in addition to depression PRS, TL and IL-6 levels. Our analysis identified one depression-associated co-methylation module (P = 0.04). Interestingly, the depression-associated module was highly enriched for pathways related to immune function and was also associated with TL and IL-6 cytokine levels. In summary, our genome-wide DNA methylation analysis of individuals with and without a self-reported history of depression identified several candidate DMRs of potential relevance to the pathogenesis of depression and its associated immune-dysfunction phenotype.

Early immune responses are independent of RGC dysfunction in glaucoma with complement component C3 being protective.

PubMed

Harder, Jeffrey M; Braine, Catherine E; Williams, Pete A; Zhu, Xianjun; MacNicoll, Katharine H; Sousa, Gregory L; Buchanan, Rebecca A; Smith, Richard S; Libby, Richard T; Howell, Gareth R; John, Simon W M

2017-05-09

Various immune response pathways are altered during early, predegenerative stages of glaucoma; however, whether the early immune responses occur secondarily to or independently of neuronal dysfunction is unclear. To investigate this relationship, we used the Wld s allele, which protects from axon dysfunction. We demonstrate that DBA/2J .Wld s mice develop high intraocular pressure (IOP) but are protected from retinal ganglion cell (RGC) dysfunction and neuroglial changes that otherwise occur early in DBA/2J glaucoma. Despite this, immune pathways are still altered in DBA/2J .Wld s mice. This suggests that immune changes are not secondary to RGC dysfunction or altered neuroglial interactions, but may be directly induced by the increased strain imposed by high IOP. One early immune response following IOP elevation is up-regulation of complement C3 in astrocytes of DBA/2J and DBA/2J. Wld s mice. Unexpectedly, because the disruption of other complement components, such as C1Q, is protective in glaucoma, C3 deficiency significantly increased the number of DBA/2J eyes with nerve damage and RGC loss at an early time point after IOP elevation. Transcriptional profiling of C3-deficient cultured astrocytes implicated EGFR signaling as a hub in C3-dependent responses. Treatment with AG1478, an EGFR inhibitor, also significantly increased the number of DBA/2J eyes with glaucoma at the same early time point. These findings suggest that C3 protects from early glaucomatous damage, a process that may involve EGFR signaling and other immune responses in the optic nerve head. Therefore, therapies that target specific components of the complement cascade, rather than global inhibition, may be more applicable for treating human glaucoma.

Early immune responses are independent of RGC dysfunction in glaucoma with complement component C3 being protective

PubMed Central

Harder, Jeffrey M.; Braine, Catherine E.; Williams, Pete A.; Zhu, Xianjun; MacNicoll, Katharine H.; Sousa, Gregory L.; Buchanan, Rebecca A.; Smith, Richard S.; Howell, Gareth R.; John, Simon W. M.

2017-01-01

Various immune response pathways are altered during early, predegenerative stages of glaucoma; however, whether the early immune responses occur secondarily to or independently of neuronal dysfunction is unclear. To investigate this relationship, we used the Wlds allele, which protects from axon dysfunction. We demonstrate that DBA/2J.Wlds mice develop high intraocular pressure (IOP) but are protected from retinal ganglion cell (RGC) dysfunction and neuroglial changes that otherwise occur early in DBA/2J glaucoma. Despite this, immune pathways are still altered in DBA/2J.Wlds mice. This suggests that immune changes are not secondary to RGC dysfunction or altered neuroglial interactions, but may be directly induced by the increased strain imposed by high IOP. One early immune response following IOP elevation is up-regulation of complement C3 in astrocytes of DBA/2J and DBA/2J.Wlds mice. Unexpectedly, because the disruption of other complement components, such as C1Q, is protective in glaucoma, C3 deficiency significantly increased the number of DBA/2J eyes with nerve damage and RGC loss at an early time point after IOP elevation. Transcriptional profiling of C3-deficient cultured astrocytes implicated EGFR signaling as a hub in C3-dependent responses. Treatment with AG1478, an EGFR inhibitor, also significantly increased the number of DBA/2J eyes with glaucoma at the same early time point. These findings suggest that C3 protects from early glaucomatous damage, a process that may involve EGFR signaling and other immune responses in the optic nerve head. Therefore, therapies that target specific components of the complement cascade, rather than global inhibition, may be more applicable for treating human glaucoma. PMID:28446616

Staphylococcal toxic shock syndrome: superantigen-mediated enhancement of endotoxin shock and adaptive immune suppression.

PubMed

Kulhankova, Katarina; King, Jessica; Salgado-Pabón, Wilmara

2014-08-01

Infectious diseases caused by Staphylococcus aureus present a significant clinical and public health problem. S. aureus causes some of the most severe hospital-associated and community-acquired illnesses. Specifically, it is the leading cause of infective endocarditis and osteomyelitis, and the second leading cause of sepsis in the USA. While pathogenesis of S. aureus infections is at the center of current research, many questions remain about the mechanisms underlying staphylococcal toxic shock syndrome (TSS) and associated adaptive immune suppression. Both conditions are mediated by staphylococcal superantigens (SAgs)-secreted staphylococcal toxins that are major S. aureus virulence factors. Toxic shock syndrome toxin-1 (TSST-1) is the SAg responsible for almost all menstrual TSS cases in the USA. TSST-1, staphylococcal enterotoxin B and C are also responsible for most cases of non-menstrual TSS. While SAgs mediate all of the hallmark features of TSS, such as fever, rash, hypotension, and multi-organ dysfunction, they are also capable of enhancing the toxic effects of endogenous endotoxin. This interaction appears to be critical in mediating the severity of TSS and related mortality. In addition, interaction between SAgs and the host immune system has been recognized to result in a unique form of adaptive immune suppression, contributing to poor outcomes of S. aureus infections. Utilizing rabbit models of S. aureus infective endocarditis, pneumonia and sepsis, and molecular genetics techniques, we aim to elucidate the mechanisms of SAg and endotoxin synergism in the pathogenesis of TSS, and examine the cellular and molecular mechanisms underlying SAg-mediated immune dysfunction.

Skeletal Muscle and Lymphocyte Mitochondrial Dysfunctions in Septic Shock Trigger ICU-Acquired Weakness and Sepsis-Induced Immunoparalysis.

PubMed

Maestraggi, Quentin; Lebas, Benjamin; Clere-Jehl, Raphaël; Ludes, Pierre-Olivier; Chamaraux-Tran, Thiên-Nga; Schneider, Francis; Diemunsch, Pierre; Geny, Bernard; Pottecher, Julien

2017-01-01

Fundamental events driving the pathological processes of septic shock-induced multiorgan failure (MOF) at the cellular and subcellular levels remain debated. Emerging data implicate mitochondrial dysfunction as a critical factor in the pathogenesis of sepsis-associated MOF. If macrocirculatory and microcirculatory dysfunctions undoubtedly participate in organ dysfunction at the early stage of septic shock, an intrinsic bioenergetic failure, sometimes called "cytopathic hypoxia," perpetuates cellular dysfunction. Short-term failure of vital organs immediately threatens patient survival but long-term recovery is also severely hindered by persistent dysfunction of organs traditionally described as nonvital, such as skeletal muscle and peripheral blood mononuclear cells (PBMCs). In this review, we will stress how and why a persistent mitochondrial dysfunction in skeletal muscles and PBMC could impair survival in patients who overcome the first acute phase of their septic episode. First, muscle wasting protracts weaning from mechanical ventilation, increases the risk of mechanical ventilator-associated pneumonia, and creates a state of ICU-acquired muscle weakness, compelling the patient to bed. Second, failure of the immune system ("immunoparalysis") translates into its inability to clear infectious foci and predisposes the patient to recurrent nosocomial infections. We will finally emphasize how mitochondrial-targeted therapies could represent a realistic strategy to promote long-term recovery after sepsis.

Regulatory immune cells in regulation of intestinal inflammatory response to microbiota

PubMed Central

Cong, Y; Liu, Z

2015-01-01

The intestinal lumen harbors nearly 100 trillion commensal bacteria that exert crucial function for health. An elaborate balance between immune responses and tolerance to intestinal microbiota is required to maintain intestinal homeostasis. This process depends on diverse regulatory mechanisms, including both innate and adaptive immunity. Dysregulation of the homeostasis between intestinal immune systems and microbiota has been shown to be associated with the development of inflammatory bowel diseases (IBD) in genetically susceptible populations. In this review, we discuss the recent progress reported in studies of distinct types of regulatory immune cells in the gut, including intestinal intraepithelial lymphocytes, Foxp3+ regulatory T cells, regulatory B cells, alternatively activated macrophages, dendritic cells, and innate lymphoid cells, and how dysfunction of this immune regulatory system contributes to intestinal diseases such as IBD. Moreover, we discuss the manipulation of these regulatory immune cells as a potential therapeutic method for management of intestinal inflammatory disorders. PMID:26080708

Regulatory immune cells in regulation of intestinal inflammatory response to microbiota.

PubMed

Sun, M; He, C; Cong, Y; Liu, Z

2015-09-01

The intestinal lumen harbors nearly 100 trillion commensal bacteria that exert crucial function for health. An elaborate balance between immune responses and tolerance to intestinal microbiota is required to maintain intestinal homeostasis. This process depends on diverse regulatory mechanisms, including both innate and adaptive immunity. Dysregulation of the homeostasis between intestinal immune systems and microbiota has been shown to be associated with the development of inflammatory bowel diseases (IBD) in genetically susceptible populations. In this review, we discuss the recent progress reported in studies of distinct types of regulatory immune cells in the gut, including intestinal intraepithelial lymphocytes, Foxp3(+) regulatory T cells, regulatory B cells, alternatively activated macrophages, dendritic cells, and innate lymphoid cells, and how dysfunction of this immune regulatory system contributes to intestinal diseases such as IBD. Moreover, we discuss the manipulation of these regulatory immune cells as a potential therapeutic method for management of intestinal inflammatory disorders.

[Thyroid dysfunction in adults infected by human immunodeficiency virus].

PubMed

Abelleira, Erika; De Cross, Graciela A; Pitoia, Fabián

2014-01-01

Patients infected with human immunodeficiency virus (HIV) have a higher prevalence of thyroid dysfunction when compared with the general population. The most frequently observed manifestations are euthyroid sick syndrome, Graves' disease and subclinical hypothyroidism. The relationship between the use of highly active antiretroviral therapy and the increased prevalence of thyroid dysfunction has been demonstrated in several series of patients. Grave's disease is recognized as a consequence of immune restitution syndrome. Besides, several studies have suggested an association between hypothyroidism and the use of nucleoside reverse transcriptase inhibitors, particularly stavudine and non-nucleoside reverse transcriptase inhibitors such as efavirenz. Further studies could provide additional evidence of the need for routine assessment of thyroid function in HIV-infected patients.

YAP is essential for Treg mediated suppression of anti-tumor immunity.

PubMed

Ni, Xuhao; Tao, Jinhui; Barbi, Joseph; Chen, Qian; Park, Benjamin V; Li, Zhiguang; Zhang, Nailing; Lebid, Andriana; Ramaswamy, Anjali; Wei, Ping; Zheng, Ying; Zhang, Xuehong; Wu, Xingmei; Vignali, Paolo D A; Yang, Cuiping; Li, Huabin; Pardoll, Drew; Lu, Ling; Pan, Duojia; Pan, Fan

2018-06-15

Regulatory T cells (Tregs) are critical for maintaining self-tolerance and immune homeostasis, but their suppressive function can impede effective anti-tumor immune responses. Foxp3 is a transcription factor expressed in Tregs that is required for their function. However, the pathways and microenvironmental cues governing Foxp3 expression and Treg function are not completely understood. Herein, we report that Yes-associated protein (YAP), a co-activator of the Hippo pathway, is highly expressed in Tregs and bolsters Foxp3 expression and Treg function in vitro and in vivo. This potentiation stemmed from YAP-dependent upregulation of Activin signaling which amplifies TGFβ/SMAD activation in Tregs. YAP-deficiency resulted in dysfunctional Tregs unable to suppress anti-tumor immunity or promote tumor growth in mice. Chemical YAP antagonism and knockout or blockade of the YAP-regulated Activin Receptor similarly improved anti-tumor immunity. Thus we identify YAP as an unexpected amplifier of a Treg-reinforcing pathway with significant potential as an anti-cancer immunotherapeutic target. Copyright ©2018, American Association for Cancer Research.

Functional changes in neutrophils and psychoneuroendocrine responses during 105 days of confinement.

PubMed

Strewe, C; Muckenthaler, F; Feuerecker, M; Yi, B; Rykova, M; Kaufmann, I; Nichiporuk, I; Vassilieva, G; Hörl, M; Matzel, S; Schelling, G; Thiel, M; Morukov, B; Choukèr, A

2015-05-01

The innate immune system as one key element of immunity and a prerequisite for an adequate host defense is of emerging interest in space research to ensure crew health and thus mission success. In ground-based studies, spaceflight-associated specifics such as confinement caused altered immune functions paralleled by changes in stress hormone levels. In this study, six men were confined for 105 days to a space module of ~500 m(3) mimicking conditions of a long-term space mission. Psychic stress was surveyed by different questionnaires. Blood, saliva, and urine samples were taken before, during, and after confinement to determine quantitative and qualitative immune responses by analyzing enumerative assays and quantifying microbicide and phagocytic functions. Additionally, expression and shedding of L-selectin (CD62L) on granulocytes and different plasma cytokine levels were measured. Cortisol and catecholamine levels were analyzed in saliva and urine. Psychic stress or an activation of the psychoneuroendocrine system could not be testified. White blood cell counts were not significantly altered, but innate immune functions showed increased cytotoxic and reduced microbicide capabilities. Furthermore, a significantly enhanced shedding of CD62L might be a hint at increased migratory capabilities. However, this was observed in the absence of any acute inflammatory state, and no rise in plasma cytokine levels was detected. In summary, confinement for 105 days caused changes in innate immune functions. Whether these changes result from an alert immune state in preparation for further immune challenges or from a normal adaptive process during confinement remains to be clarified in future research. Copyright © 2015 the American Physiological Society.

Transcriptomic and proteomic responses of Serratia marcescens to spaceflight conditions involve large-scale changes in metabolic pathways

NASA Astrophysics Data System (ADS)

Wang, Yajuan; Yuan, Yanting; Liu, Jinwen; Su, Longxiang; Chang, De; Guo, Yinghua; Chen, Zhenhong; Fang, Xiangqun; Wang, Junfeng; Li, Tianzhi; Zhou, Lisha; Fang, Chengxiang; Yang, Ruifu; Liu, Changting

2014-04-01

The microgravity environment of spaceflight expeditions has been associated with altered microbial responses. This study explores the characterization of Serratia marcescensis grown in a spaceflight environment at the phenotypic, transcriptomic and proteomic levels. From November 1, 2011 to November 17, 2011, a strain of S. marcescensis was sent into space for 398 h on the Shenzhou VIII spacecraft, and ground simulation was performed as a control (LCT-SM213). After the flight, two mutant strains (LCT-SM166 and LCT-SM262) were selected for further analysis. Although no changes in the morphology, post-culture growth kinetics, hemolysis or antibiotic sensitivity were observed, the two mutant strains exhibited significant changes in their metabolic profiles after exposure to spaceflight. Enrichment analysis of the transcriptome showed that the differentially expressed genes of the two spaceflight strains and the ground control strain mainly included those involved in metabolism and degradation. The proteome revealed that changes at the protein level were also associated with metabolic functions, such as glycolysis/gluconeogenesis, pyruvate metabolism, arginine and proline metabolism and the degradation of valine, leucine and isoleucine. In summary S. marcescens showed alterations primarily in genes and proteins that were associated with metabolism under spaceflight conditions, which gave us valuable clues for future research.

Drugs in space: Pharmacokinetics and pharmacodynamics in astronauts.

PubMed

Kast, Johannes; Yu, Yichao; Seubert, Christoph N; Wotring, Virginia E; Derendorf, Hartmut

2017-11-15

Space agencies are working intensely to push the current boundaries of human spaceflight by sending astronauts deeper into space than ever before, including missions to Mars and asteroids. Spaceflight alters human physiology due to fluid shifts, muscle and bone loss, immune system dysregulation, and changes in the gastrointestinal tract and metabolic enzymes. These alterations may change the pharmacokinetics and/or pharmacodynamics of medications used by astronauts and subsequently might impact drug efficacy and safety. Most commonly, medications are administered during space missions to treat sleep disturbances, allergies, space motion sickness, pain, and sinus congestion. These medications are administered under the assumption that they act in a similar way as on Earth, an assumption that has not been investigated systematically yet. Few inflight pharmacokinetic data have been published, and pharmacodynamic and pharmacokinetic/pharmacodynamic studies during spaceflight are also lacking. Therefore, bed-rest models are often used to simulate physiological changes observed during microgravity. In addition to pharmacokinetic/pharmacodynamic changes, decreased drug and formulation stability in space could also influence efficacy and safety of medications. These alterations along with physiological changes and their resulting pharmacokinetic and pharmacodynamic effects must to be considered to determine their ultimate impact on medication efficacy and safety during spaceflight. Copyright © 2017 Elsevier B.V. All rights reserved.

miR-29b and miR-198 overexpression in CD8+ T cells of renal cell carcinoma patients down-modulates JAK3 and MCL-1 leading to immune dysfunction.

PubMed

Gigante, Margherita; Pontrelli, Paola; Herr, Wolfgang; Gigante, Maddalena; D'Avenia, Morena; Zaza, Gianluigi; Cavalcanti, Elisabetta; Accetturo, Matteo; Lucarelli, Giuseppe; Carrieri, Giuseppe; Battaglia, Michele; Storkus, Walter J; Gesualdo, Loreto; Ranieri, Elena

2016-04-11

Mammalian microRNAs (miR) regulate the expression of genes relevant for the development of adaptive and innate immunity against cancer. Since T cell dysfunction has previously been reported in patients with renal cell carcinoma (RCC; clear cell type), we aimed to analyze these immune cells for genetic and protein differences when compared to normal donor T cells freshly after isolation and 35 days after in vitro stimulation (IVS) with HLA-matched RCC tumor cells. We investigated gene expression profiles of tumor-reactive CD8(+) T cells obtained from RCC patient and compared with their HLA-matched healthy sibling donors using a microarray approach. In addition, miRNAs analysis was performed in a validation cohort of peripheral blood CD8(+) T cells from 25 RCC patients compared to 15 healthy volunteers. We observed that CD8(+) T cells from RCC patients expressed reduced levels of anti-apoptotic and proliferation-associated gene products when compared with normal donor T cells both pre- and post-IVS. In particular, JAK3 and MCL-1 were down-regulated in patient CD8(+) T cells versus their normal counterparts, likely due to defective suppressor activity of miR-29b and miR-198 in RCC CD8(+) T cells. Indeed, specific inhibition of miR-29b or miR-198 in peripheral blood mononuclear cells (PBMCs) isolated from RCC patients, resulted in the up-regulation of JAK3 and MCL-1 proteins and significant improvement of cell survival in vitro. Our results suggest that miR-29b and miR-198 dysregulation in RCC patient CD8(+) T cells is associated with dysfunctional immunity and foreshadow the development of miR-targeted therapeutics to correct such T cell defects in vivo.

CD8+T cells expressing both PD-1 and TIGIT but not CD226 are dysfunctional in acute myeloid leukemia (AML) patients.

PubMed

Wang, Mengjie; Bu, Jin; Zhou, Maohua; Sido, Jessica; Lin, Yu; Liu, Guanfang; Lin, Qiwen; Xu, Xiuzhang; Leavenworth, Jianmei W; Shen, Erxia

2018-05-01

Acute myeloid leukemia (AML) is one of the most common types of leukemia among adults with an overall poor prognosis and very limited treatment management. Immune checkpoint blockade of PD-1 alone or combined with other immune checkpoint blockade has gained impressive results in murine AML models by improving anti-leukemia CD8 + T cell function, which has greatly promoted the strategy to utilize combined immune checkpoint inhibitors to treat AML patients. However, the expression profiles of these immune checkpoint receptors, such as co-inhibitory receptors PD-1 and TIGIT and co-stimulatory receptor CD226, in T cells from AML patients have not been clearly defined. Here we have defined subsets of CD8 + and CD4 + T cells in the peripheral blood (PB) from newly diagnosed AML patients and healthy controls (HCs). We have observed increased frequencies of PD-1- and TIGIT- expressing CD8 + T cells but decreased occurrence of CD226-expressing CD8 + T cells in AML patients. Further analysis of these CD8 + T cells revealed a unique CD8 + T cell subset that expressed PD-1 and TIGIT but displayed lower levels of CD226 was associated with failure to achieve remission after induction chemotherapy and FLT3-ITD mutations which predict poor clinical prognosis in AML patients. Importantly, these PD-1 + TIGIT + CD226 - CD8 + T cells are dysfunctional with lower expression of intracellular IFN-γ and TNF-α than their counterparts in HCs. Therefore, our studies revealed that an increased frequency of a unique CD8 + T cell subset, PD-1 + TIGIT + CD226 - CD8 + T cells, is associated with CD8 + T cell dysfunction and poor clinical prognosis of AML patients, which may reveal critical diagnostic or prognostic biomarkers and direct more efficient therapeutic strategies. Copyright © 2017. Published by Elsevier Inc.

Got worms? Perinatal exposure to helminths prevents persistent immune sensitization and cognitive dysfunction induced by early-life infection.

PubMed

Williamson, Lauren L; McKenney, Erin A; Holzknecht, Zoie E; Belliveau, Christine; Rawls, John F; Poulton, Susan; Parker, William; Bilbo, Staci D

2016-01-01

The incidence of autoimmune and inflammatory diseases has risen dramatically in post-industrial societies. "Biome depletion" - loss of commensal microbial and multicellular organisms such as helminths (intestinal worms) that profoundly modulate the immune system - may contribute to these increases. Hyperimmune-associated disorders also affect the brain, especially neurodevelopment, and increasing evidence links early-life infection to cognitive and neurodevelopmental disorders. We have demonstrated previously that rats infected with bacteria as newborns display life-long vulnerabilities to cognitive dysfunction, a vulnerability that is specifically linked to long-term hypersensitivity of microglial cell function, the resident immune cells of the brain. Here, we demonstrate that helminth colonization of pregnant dams attenuated the exaggerated brain cytokine response of their offspring to bacterial infection, and that combined with post-weaning colonization of offspring with helminths (consistent with their mothers treatment) completely prevented enduring microglial sensitization and cognitive dysfunction in adulthood. Importantly, helminths had no overt impact on adaptive immune cell subsets, whereas exaggerated innate inflammatory responses in splenic macrophages were prevented. Finally, helminths altered the effect of neonatal infection on the gut microbiome; neonatal infection with Escherichia coli caused a shift from genera within the Actinobacteria and Tenericutes phyla to genera in the Bacteroidetes phylum in rats not colonized with helminths, but helminths attenuated this effect. In sum, these data point toward an inter-relatedness of various components of the biome, and suggest potential mechanisms by which this helminth might exert therapeutic benefits in the treatment of neuroinflammatory and cognitive disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

Aging and Immune Function: Molecular Mechanisms to Interventions

PubMed Central

Ponnappan, Subramaniam

2011-01-01

Abstract The immune system of an organism is an essential component of the defense mechanism aimed at combating pathogenic stress. Age-associated immune dysfunction, also dubbed “immune senescence,” manifests as increased susceptibility to infections, increased onset and progression of autoimmune diseases, and onset of neoplasia. Over the years, extensive research has generated consensus in terms of the phenotypic and functional defects within the immune system in various organisms, including humans. Indeed, age-associated alterations such as thymic involution, T cell repertoire skewing, decreased ability to activate naïve T cells and to generate robust memory responses, have been shown to have a causative role in immune decline. Further, understanding the molecular mechanisms underlying the generation of proteotoxic stress, DNA damage response, modulation of ubiquitin proteasome pathway, and regulation of transcription factor NFκB activation, in immune decline, have paved the way to delineating signaling pathways that cross-talk and impact immune senescence. Given the role of the immune system in combating infections, its effectiveness with age may well be a marker of health and a predictor of longevity. It is therefore believed that a better understanding of the mechanisms underlying immune senescence will lead to an effective interventional strategy aimed at improving the health span of individuals. Antioxid. Redox Signal. 14, 1551–1585. PMID:20812785

Translational Cellular Research on the International Space Station

NASA Technical Reports Server (NTRS)

Love, John; Cooley, Vic

2016-01-01

The emerging field of Translational Research aims to coalesce interdisciplinary findings from basic science for biomedical applications. To complement spaceflight research using human subjects, translational studies can be designed to address aspects of space-related human health risks and help develop countermeasures to prevent or mitigate them, with therapeutical benefits for analogous conditions experienced on Earth. Translational research with cells and model organisms is being conducted onboard the International Space Station (ISS) in connection with various human systems impacted by spaceflight, such as the cardiovascular, musculoskeletal, and immune systems. Examples of recent cell-based translational investigations on the ISS include the following. The JAXA investigation Cell Mechanosensing seeks to identify gravity sensors in skeletal muscle cells to develop muscle atrophy countermeasures by analyzing tension fluctuations in the plasma membrane, which changes the expression of key proteins and genes. Earth applications of this study include therapeutic approaches for some forms of muscular dystrophy, which appear to parallel aspects of muscle wasting in space. Spheroids is an ESA investigation examining the system of endothelial cells lining the inner surface of all blood vessels in terms of vessel formation, cellular proliferation, and programmed cell death, because injury to the endothelium has been implicated as underpinning various cardiovascular and musculoskeletal problems arising during spaceflight. Since endothelial cells are involved in the functional integrity of the vascular wall, this research has applications to Earth diseases such as atherosclerosis, diabetes, and hypertension. The goal of the T-Cell Activation in Aging NASA investigation is to understand human immune system depression in microgravity by identifying gene expression patterns of candidate molecular regulators, which will provide further insight into factors that may play a critical role in immune function loss during aging. In addition, Omics investigations with cells have synergistic applications ranging from the evaluation of pharmacological countermeasures to drug discovery. Thus, cell-based translational research onboard the ISS is bidirectionally bridging cutting-edge cellular and molecular approaches with space bioastronautics and human health methodologies on Earth.

Effect of Spaceflight on the Functions of NK and LAK Cells

NASA Technical Reports Server (NTRS)

Pierson, Duane L.; Grimm, Elizabeth A.; Pierson, Duane L.; Paloski, W. H. (Technical Monitor)

1999-01-01

Spaceflight-associated stress alters some aspects of the human immune response. In this study, we determined the effects of 10 days aboard the Space Shuttle on the cytotoxic activity of NK and LAK cells. The subjects of this study were crewmembers of two 10-day shuttle flights. Ten-ml blood specimens were obtained from ten astronauts 10 days before launch, immediately after landing, and 3 days after landing. PBMCs were separated from the blood specimens and stored at -800 C. All PBMCs were thawed simultaneously, and the cytotoxic activities of NK and LAK cells were measured by a 4-hour Cr-51 release assay. K562 cells were used to assess NK-cell cytotoxicity. After 4 days of IL-2 activation, the LAK cell cytotoxic activity was determined using K562 and Daudi cells as the target cells. NK-cell cytotoxicity was decreased at landing (p less than 0.0005) in 9/10 astronauts, and in most cases recovered to preflight levels by 3 days after landing; NK-cell cytotoxicity was increased in one astronaut at landing. LAK cytotoxic activity against K562 cells was decreased at landing in 6/10 astronauts (p=0.018), and activity against Daudi cells was decreased in 7/10 astronauts (p=0.01). Phenotyping of PBMCs and LAK cells showed alterations in some surface markers and adhesion molecules (CD1 1 b, CD1 1 c, CD1 1 a, CD1 6, L-Selectin and CD3). Thus spaceflight leads to a decrease in the functions of NK and LAK cells in most astronauts.

Head and Neck Carcinoma Immunotherapy: Facts and Hopes.

PubMed

Whiteside, Theresa L

2018-01-01

Cancer of the head and neck (HNC) is a heterogeneous disease of the upper aerodigestive tract, encompassing distinct histologic types, different anatomic sites, and human papillomavirus (HPV)-positive as well as HPV-negative cancers. Advanced/recurrent HNCs have poor prognosis with low survival rates. Tumor-mediated inhibition of antitumor immune responses and a high mutational burden are common features of HNCs. Both are responsible for the successful escape of these tumors from the host immune system. HNCs evolve numerous mechanisms of evasion from immune destruction. These mechanisms are linked to genetic aberrations, so that HNCs with a high mutational load are also highly immunosuppressive. The tumor microenvironment of these cancers is populated by immune cells that are dysfunctional, inhibitory cytokines, and exosomes carrying suppressive ligands. Dysfunctional immune cells in patients with recurrent/metastatic HNC can be made effective by the delivery of immunotherapies in combination with conventional treatments. With many promising immune-based strategies available, the future of immune therapies in HNC is encouraging, especially as methods for genetic profiling and mapping the immune landscape of the tumor are being integrated into a personalized approach. Efficiency of immune therapies is expected to rapidly improve with the possibility for patients' selection based on personal immunogenomic profiles. Noninvasive biomarkers of response to therapy will be emerging as a better understanding of the various molecular signals co-opted by the tumors is gained. The emerging role of immunotherapy as a potentially beneficial addition to standard treatments for recurrent/metastatic HNC offers hope to the patients for whom no other therapeutic options exist. Clin Cancer Res; 24(1); 6-13. ©2017 AACR . ©2017 American Association for Cancer Research.

Validation of Procedures for Monitoring Crewmember Immune Function

NASA Technical Reports Server (NTRS)

Pierson, Duane; Crucian, Brian; Mehta, Satish; Stowe, Raymond; Uchakin, Peter; Quiriarte, Heather; Sams, Clarence

2010-01-01

The objective of this Supplemental Medical Objective (SMO) is to determine the status of the immune system, physiological stress and latent viral reactivation (a clinical outcome that can be measured) during both short and long-duration spaceflight. In addition, this study will develop and validate an immune monitoring strategy consistent with operational flight requirements and constraints. Pre-mission, in-flight and post-flight blood and saliva samples will be obtained from participating crewmembers. Assays included peripheral immunophenotype, T cell function, cytokine profiles, viral-specific immunity, latent viral reactivation (EBV, CMV, VZV), and stress hormone measurements. To date, 18 short duration (now completed) and 8 long-duration crewmembers have completed the study. The long-duration phase of this study is ongoing. For this presentation, the final data set for the short duration subjects will be discussed.

Suppression of Antigen-Specific Lymphocyte Activation in Simulated Microgravity

NASA Technical Reports Server (NTRS)

Cooper, David; Pride, Michael W.; Brown, Eric L.; Risin, Diana; Pellis, Neal R.

1999-01-01

Various parameters of immune suppression are observed in astronauts during and after spaceflight, and in isolated immune cells in true and simulated microgravity. Specifically, polyclonal activation of T cells is severely suppressed in true and simulated microgravity. These recent findings with various polyclonal activators suggests a suppression of oligoclonal lymphocyte activation in microgravity. We utilized rotating wall vessel (RWV) bioreactors that simulate aspects of microgravity for cell cultures to analyze three models of antigen-specific activation. A mixed-lymphocyte reaction (MLR), as a model for a primary immune response; a tetanus toxoid (TT) response and a B. burgdorferi (Bb) response, as models of a secondary immune response, were all suppressed in the RWV bioreactor. Our findings confirm that the suppression of activation observed with polyclonal models also encompasses oligoclonal antigen-specific activation.

Ames Research Center life sciences payload - Overview of results of a spaceflight of 24 rats and 2 monkeys

NASA Technical Reports Server (NTRS)

Callahan, P. X.; Schatte, C.; Grindeland, R. E.; Bowman, G.; Lencki, W. A.

1985-01-01

Engineering and biological data gathered with the research animal holding facilities (RAHFs) used on the Spacelab 3 mission are summarized. The animals totaled 24 rats and two squirrel monkeys. The RAHFs included biotelemetry, cameras and environmental monitoring equipment. The primary mission goal was engineering evaluation of the RAHFs and ancillary equipment. Tightly-fitted seals were found to be a necessity for keeping waste and food particles from contaminating the Spacelab equipment. All the rats returned with little muscle tone and suppressed immune systems. The monkeys displayed highly individual responses to spaceflight. Both species exhibited reduced abilities to maintain meticulously clean furs in weightlessness. Details of several physiological changes detected during post-flight autopsies are provided.

Sepsis-induced immunosuppression: from cellular dysfunctions to immunotherapy

PubMed Central

Hotchkiss, Richard S.; Monneret, Guillaume; Payen, Didier

2014-01-01

Sepsis — severe life-threatening infection with organ dysfunction — initiates a complex interplay of host pro- and anti-inflammatory processes. In a real sense, sepsis can be considered a race to the death between the pathogens and the host immune system. It is the proper balance between the often competing pro- and anti-inflammatory pathways that determines the fate of the individual. Although the field of sepsis research has witnessed the failure of many highly-touted clinical trials, a better understanding of the pathophysiological basis of the disorder and the mechanisms responsible for the associated pro- and anti-inflammatory responses is leading to a novel approach to treat this highly lethal condition. Biomarker-guided immunotherapy administered to patients at the proper immune phase of sepsis represents a potential major advance in the treatment of sepsis and more broadly in the field of infectious disease. PMID:24232462

BIOMARKERS for CHRONIC FATIGUE

PubMed Central

Broderick, Gordon; Fletcher, Mary Ann

2012-01-01

Fatigue that persists for 6 months or more is termed chronic fatigue. Chronic fatigue (CF) in combination with a minimum of 4 of 8 symptoms and the absence of diseases that could explain these symptoms, constitute the case definition for chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). Inflammation, immune system activation, autonomic dysfunction, impaired functioning in the hypothalamic-pituitary-adrenal axis, and neuroendocrine dysregulation have all been suggested as root causes of fatigue. The identification of objective markers consistently associated with CFS/ME is an important goal in relation to diagnosis and treatment, as the current case definitions are based entirely on physical signs and symptoms. This review is focused on the recent literature related to biomarkers for fatigue associated with CFS/ME and, for comparison, those associated with other diseases. These markers are distributed across several of the body’s core regulatory systems. A complex construct of symptoms emerges from alterations and/or dysfunctions in the nervous, endocrine and immune systems. We propose that new insight will depend on our ability to develop and deploy an integrative profiling of CFS/ME pathogenesis at the molecular level. Until such a molecular signature is obtained efforts to develop effective treatments will continue to be severely limited. PMID:22732129

‘Trained immunity’: consequences for lymphoid malignancies

PubMed Central

Stevens, Wendy B.C.; Netea, Mihai G.; Kater, Arnon P.; van der Velden, Walter J.F.M.

2016-01-01

In hematological malignancies complex interactions exist between the immune system, microorganisms and malignant cells. On one hand, microorganisms can induce cancer, as illustrated by specific infection-induced lymphoproliferative diseases such as Helicobacter pylori-associated gastric mucosa-associated lymphoid tissue lymphoma. On the other hand, malignant cells create an immunosuppressive environment for their own benefit, but this also results in an increased risk of infections. Disrupted innate immunity contributes to the neoplastic transformation of blood cells by several mechanisms, including the uncontrolled clearance of microbial and autoantigens resulting in chronic immune stimulation and proliferation, chronic inflammation, and defective immune surveillance and anti-cancer immunity. Restoring dysfunction or enhancing responsiveness of the innate immune system might therefore represent a new angle for the prevention and treatment of hematological malignancies, in particular lymphoid malignancies and associated infections. Recently, it has been shown that cells of the innate immune system, such as monocytes/macrophages and natural killer cells, harbor features of immunological memory and display enhanced functionality long-term after stimulation with certain microorganisms and vaccines. These functional changes rely on epigenetic reprogramming and have been termed ‘trained immunity’. In this review the concept of ‘trained immunity’ is discussed in the setting of lymphoid malignancies. Amelioration of infectious complications and hematological disease progression can be envisioned to result from the induction of trained immunity, but future studies are required to prove this exciting new hypothesis. PMID:27903713

‘‘Omics’’ of Selenium Biology: A Prospective Study of Plasma Proteome Network Before and After Selenized-Yeast Supplementation in Healthy Men

USDA-ARS?s Scientific Manuscript database

Low selenium levels have been linked to a higher incidence of cancer and other diseases, including Keshan,Chagas, and Kashin–Beck, and insulin resistance. Additionally, muscle and cardiovascular disorders, immune dysfunction, cancer, neurological disorders, and endocrine function have been associate...

Transcriptome analysis reveals persistent effects of neonatal diet on small intestine gene expression profile in a porcine model

USDA-ARS?s Scientific Manuscript database

Breastfeeding is associated with several benefits affecting gut development and immune function. Compared to breast feeding, infant formula feeding is linked to a greater risk for gut dysfunction, ear and respiratory tract infections, and allergies. The beneficial effects appear to last at least thr...

Soluble TNFα Signaling within the Spinal Cord Contributes to the Development of Autonomic Dysreflexia and Ensuing Vascular and Immune Dysfunction after Spinal Cord Injury.

PubMed

Mironets, Eugene; Osei-Owusu, Patrick; Bracchi-Ricard, Valerie; Fischer, Roman; Owens, Elizabeth A; Ricard, Jerome; Wu, Di; Saltos, Tatiana; Collyer, Eileen; Hou, Shaoping; Bethea, John R; Tom, Veronica J

2018-04-25

Cardiovascular disease and susceptibility to infection are leading causes of morbidity and mortality for individuals with spinal cord injury (SCI). A major contributor to these is autonomic dysreflexia (AD), an amplified reaction of the autonomic nervous system (hallmarked by severe hypertension) in response to sensory stimuli below the injury. Maladaptive plasticity of the spinal sympathetic reflex circuit below the SCI results in AD intensification over time. Mechanisms underlying this maladaptive plasticity are poorly understood, restricting the identification of treatments. Thus, no preventative treatments are currently available. Neuroinflammation has been implicated in other pathologies associated with hyperexcitable neural circuits. Specifically, the soluble form of TNFα (sTNFα) is known to play a role in neuroplasticity. We hypothesize that persistent expression of sTNFα in spinal cord underlies AD exacerbation. To test this, we intrathecally administered XPro1595, a biologic that renders sTNFα nonfunctional, after complete, high-level SCI in female rats. This dramatically attenuated the intensification of colorectal distension-induced and naturally occurring AD events. This improvement is mediated via decreased sprouting of nociceptive primary afferents and activation of the spinal sympathetic reflex circuit. We also examined peripheral vascular function using ex vivo pressurized arterial preparations and immune function via flow cytometric analysis of splenocytes. Diminishing AD via pharmacological inhibition of sTNFα mitigated ensuing vascular hypersensitivity and immune dysfunction. This is the first demonstration that neuroinflammation-induced sTNFα is critical for altering the spinal sympathetic reflex circuit, elucidating a novel mechanism for AD. Importantly, we identify the first potential pharmacological, prophylactic treatment for this life-threatening syndrome. SIGNIFICANCE STATEMENT Autonomic dysreflexia (AD), a disorder that develops after spinal cord injury (SCI) and is hallmarked by sudden, extreme hypertension, contributes to cardiovascular disease and susceptibility to infection, respectively, two leading causes of mortality and morbidity in SCI patients. We demonstrate that neuroinflammation-induced expression of soluble TNFα plays a critical role in AD, elucidating a novel underlying mechanism. We found that intrathecal administration after SCI of a biologic that inhibits soluble TNFα signaling dramatically attenuates AD and significantly reduces AD-associated peripheral vascular and immune dysfunction. We identified mechanisms behind diminished plasticity of neuronal populations within the spinal sympathetic reflex circuit. This study is the first to pinpoint a potential pharmacological, prophylactic strategy to attenuate AD and ensuing cardiovascular and immune dysfunction. Copyright © 2018 the authors 0270-6474/18/384147-17$15.00/0.

Inflammatory response and extracorporeal circulation.

PubMed

Kraft, Florian; Schmidt, Christoph; Van Aken, Hugo; Zarbock, Alexander

2015-06-01

Patients undergoing cardiac surgery with extracorporeal circulation (EC) frequently develop a systemic inflammatory response syndrome. Surgical trauma, ischaemia-reperfusion injury, endotoxaemia and blood contact to nonendothelial circuit compounds promote the activation of coagulation pathways, complement factors and a cellular immune response. This review discusses the multiple pathways leading to endothelial cell activation, neutrophil recruitment and production of reactive oxygen species and nitric oxide. All these factors may induce cellular damage and subsequent organ injury. Multiple organ dysfunction after cardiac surgery with EC is associated with an increased morbidity and mortality. In addition to the pathogenesis of organ dysfunction after EC, this review deals with different therapeutic interventions aiming to alleviate the inflammatory response and consequently multiple organ dysfunction after cardiac surgery. Copyright © 2015 Elsevier Ltd. All rights reserved.

iss051e029016

NASA Image and Video Library

2017-04-28

iss051e029016 (4/28/2017) --- Crew members on the International Space Station completed a new session of the Genes in Space 2 investigation. Spaceflight causes many changes to the human body, including alterations in DNA and a weakened immune system. This study uses a new technology to study DNA in space to try and safeguard crew health. Credits: NASA

iss051e044502

NASA Image and Video Library

2017-05-17

iss051e044502 (5/17/2017) --- Crew members on the International Space Station completed a new session of the Genes in Space 2 investigation. Spaceflight causes many changes to the human body, including alterations in DNA and a weakened immune system. This study uses a new technology to study DNA in space to try and safeguard crew health. Credits: NASA

iss051e044497

NASA Image and Video Library

2017-05-17

iss051e044497 (5/17/2017) --- Crew members on the International Space Station completed a new session of the Genes in Space 2 investigation. Spaceflight causes many changes to the human body, including alterations in DNA and a weakened immune system. This study uses a new technology to study DNA in space to try and safeguard crew health. Credits: NASA

Models to study gravitational biology of Mammalian reproduction

NASA Technical Reports Server (NTRS)

Tou, Janet; Ronca, April; Grindeland, Richard; Wade, Charles

2002-01-01

Mammalian reproduction evolved within Earth's 1-g gravitational field. As we move closer to the reality of space habitation, there is growing scientific interest in how different gravitational states influence reproduction in mammals. Habitation of space and extended spaceflight missions require prolonged exposure to decreased gravity (hypogravity, i.e., weightlessness). Lift-off and re-entry of the spacecraft are associated with exposure to increased gravity (hypergravity). Existing data suggest that spaceflight is associated with a constellation of changes in reproductive physiology and function. However, limited spaceflight opportunities and confounding effects of various nongravitational factors associated with spaceflight (i.e., radiation, stress) have led to the development of ground-based models for studying the effects of altered gravity on biological systems. Human bed rest and rodent hindlimb unloading paradigms are used to study exposure to hypogravity. Centrifugation is used to study hypergravity. Here, we review the results of spaceflight and ground-based models of altered gravity on reproductive physiology. Studies utilizing ground-based models that simulate hyper- and hypogravity have produced reproductive results similar to those obtained from spaceflight and are contributing new information on biological responses across the gravity continuum, thereby confirming the appropriateness of these models for studying reproductive responses to altered gravity and the underlying mechanisms of these responses. Together, these unique tools are yielding new insights into the gravitational biology of reproduction in mammals.

Evidence Report: Risk of Crew Adverse Health Event Due to Altered Immune Response

NASA Technical Reports Server (NTRS)

Crucian, Brian; Sams, Clarence F.

2013-01-01

The Risk of Crew Adverse Health Event Due to Altered Immune Response is identified by the National Aeronautics and Space Administration (NASA) Human Research Program (HRP) as a recognized risk to human health and performance in space. The HRP Program Requirements Document (PRD) defines these risks. This Evidence Report provides a summary of the evidence that has been used to identify and characterize this risk. It is known that human immune function is altered in- and post-flight, but it is unclear at present if such alterations lead to increased susceptibility to disease. Reactivation of latent viruses has been documented in crewmembers, although this reactivation has not been directly correlated with immune changes or with observed diseases. As described in this report, further research is required to better characterize the relationships between altered immune response and susceptibility to disease during and after spaceflight. This is particularly important for future deep-space exploration missions.

Curcumin reverses T cell-mediated adaptive immune dysfunctions in tumor-bearing hosts.

PubMed

Bhattacharyya, Sankar; Md Sakib Hossain, Dewan; Mohanty, Suchismita; Sankar Sen, Gouri; Chattopadhyay, Sreya; Banerjee, Shuvomoy; Chakraborty, Juni; Das, Kaushik; Sarkar, Diptendra; Das, Tanya; Sa, Gaurisankar

2010-07-01

Immune dysfunction is well documented during tumor progression and likely contributes to tumor immune evasion. CD8(+) cytotoxic T lymphocytes (CTLs) are involved in antigen-specific tumor destruction and CD4(+) T cells are essential for helping this CD8(+) T cell-dependent tumor eradication. Tumors often target and inhibit T-cell function to escape from immune surveillance. This dysfunction includes loss of effector and memory T cells, bias towards type 2 cytokines and expansion of T regulatory (Treg) cells. Curcumin has previously been shown to have antitumor activity and some research has addressed the immunoprotective potential of this plant-derived polyphenol in tumor-bearing hosts. Here we examined the role of curcumin in the prevention of tumor-induced dysfunction of T cell-based immune responses. We observed severe loss of both effector and memory T-cell populations, downregulation of type 1 and upregulation of type 2 immune responses and decreased proliferation of effector T cells in the presence of tumors. Curcumin, in turn, prevented this loss of T cells, expanded central memory T cell (T(CM))/effector memory T cell (T(EM)) populations, reversed the type 2 immune bias and attenuated the tumor-induced inhibition of T-cell proliferation in tumor-bearing hosts. Further investigation revealed that tumor burden upregulated Treg cell populations and stimulated the production of the immunosuppressive cytokines transforming growth factor (TGF)-beta and IL-10 in these cells. Curcumin, however, inhibited the suppressive activity of Treg cells by downregulating the production of TGF-beta and IL-10 in these cells. More importantly, curcumin treatment enhanced the ability of effector T cells to kill cancer cells. Overall, our observations suggest that the unique properties of curcumin may be exploited for successful attenuation of tumor-induced suppression of cell-mediated immune responses.

Modeling locomotor dysfunction following spaceflight with Galvanic vestibular stimulation.

PubMed

Moore, Steven T; MacDougall, Hamish G; Peters, Brian T; Bloomberg, Jacob J; Curthoys, Ian S; Cohen, Helen S

2006-10-01

In this study locomotor and gaze dysfunction commonly observed in astronauts following spaceflight were modeled using two Galvanic vestibular stimulation (GVS) paradigms: (1) pseudorandom, and (2) head-coupled (proportional to the summed vertical linear acceleration and yaw angular velocity obtained from a head-mounted Inertial Measurement Unit). Locomotor and gaze function during GVS were assessed by tests previously used to evaluate post-flight astronaut performance; dynamic visual acuity (DVA) during treadmill locomotion at 80 m/min, and navigation of an obstacle course. During treadmill locomotion with pseudorandom GVS there was a 12% decrease in coherence between head pitch and vertical translation at the step frequency relative to the no GVS condition, which was not significantly different to the 15% decrease in coherence observed in astronauts following shuttle missions. This disruption in head stabilization likely resulted in a decrease in DVA equivalent to the reduction in acuity observed in astronauts 6 days after return from extended missions aboard the International Space Station (ISS). There were significant increases in time-to-completion of the obstacle course during both pseudorandom (21%) and head-coupled (14%) GVS, equivalent to an ISS astronaut 5 days post-landing. An attempt to suppress head movement was evident during both pseudorandom and head-coupled GVS while negotiating the obstacle course, with a 20 and 16%, decrease in head pitch and yaw velocity, respectively. The results of this study demonstrate that pseudorandom GVS generates many of the salient features of post-flight locomotor dysfunction observed in astronauts following short and long duration missions. An ambulatory GVS system may prove a useful adjunct to the current pre-flight astronaut training regimen.

Extracellular vesicles are key intercellular mediators in the development of immune dysfunction to allergens in the airways.

PubMed

Shin, T-S; Kim, J H; Kim, Y-S; Jeon, S G; Zhu, Z; Gho, Yong Song; Kim, Yoon-Keun

2010-10-01

Previous evidence indicates that inhalation of lipopolysaccharide (LPS)-containing with allergens induced mixed Th1 and Th17 cell responses in the airways. Extracellular vesicles (EVs) are nanometer-sized spherical, lipid-bilayered structures and are recently in the public eye as an intercellular communicator in immune responses. To evaluate the role of EVs secreted by LPS inhalation in the development of airway immune dysfunction in response to allergens. Extracellular vesicles in bronchoalveolar lavage fluids of BALB/c mice were isolated and characterized 24 h after applications to the airway of 10 μg of LPS for 3 days. To evaluate the role of LPS-induced EVs on the development of airway immune dysfunction, in vivo and in vitro experiments were performed using the isolated LPS-induced EVs. The inhalation of LPS enhanced EVs release into the BAL fluid, when compared to the application of PBS. Airway sensitization with allergens and LPS-induced EVs resulted in a mixed Th1 and Th17 cell responses, although that with allergens and PBS-induced EVs induced immune tolerance. In addition, LPS-induced EVs enhanced the production of Th1- and Th17-polarizing cytokines (IL-12p70 and IL-6, respectively) by lung dendritic cells. Moreover, the immune responses induced by the LPS-induced EVs were blocked by denaturation of the EV-bearing proteins. These data suggest that EVs (especially, the protein components) secreted by LPS inhalation are a key intercellular communicator in the development of airway immune dysfunction to inhaled LPS-containing allergens.

Extracellular vesicles are key intercellular mediators in the development of immune dysfunction to allergens in the airways

PubMed Central

Shin, T-S; Kim, J H; Kim, Y-S; Jeon, S G; Zhu, Z; Gho, Y S; Kim, Y-K

2010-01-01

Background Previous evidence indicates that inhalation of lipopolysaccharide (LPS)-containing with allergens induced mixed Th1 and Th17 cell responses in the airways. Extracellular vesicles (EVs) are nanometer-sized spherical, lipid-bilayered structures and are recently in the public eye as an intercellular communicator in immune responses. Objective To evaluate the role of EVs secreted by LPS inhalation in the development of airway immune dysfunction in response to allergens. Methods Extracellular vesicles in bronchoalveolar lavage fluids of BALB/c mice were isolated and characterized 24 h after applications to the airway of 10 μg of LPS for 3 days. To evaluate the role of LPS-induced EVs on the development of airway immune dysfunction, in vivo and in vitro experiments were performed using the isolated LPS-induced EVs. Results The inhalation of LPS enhanced EVs release into the BAL fluid, when compared to the application of PBS. Airway sensitization with allergens and LPS-induced EVs resulted in a mixed Th1 and Th17 cell responses, although that with allergens and PBS-induced EVs induced immune tolerance. In addition, LPS-induced EVs enhanced the production of Th1- and Th17-polarizing cytokines (IL-12p70 and IL-6, respectively) by lung dendritic cells. Moreover, the immune responses induced by the LPS-induced EVs were blocked by denaturation of the EV-bearing proteins. Conclusion These data suggest that EVs (especially, the protein components) secreted by LPS inhalation are a key intercellular communicator in the development of airway immune dysfunction to inhaled LPS-containing allergens. PMID:20337607

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

PubMed

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.

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

PubMed Central

Zhong, Hong; Ma, Minjuan

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. PMID:29484304

Antiorthostatic suspension for 14 days does not diminish the oxidative response of neutrophils in mice

NASA Technical Reports Server (NTRS)

Smolen, J. E.; Fossett, M. C.; Joe, Y.; Prince, J. E.; Priest, E.; Kanwar, S.; Smith, C. W.

2000-01-01

The effects of long-term spaceflight on inflammatory responses have not been well-studied in either humans or animals. It is thus important to determine if the functions of immune and inflammatory cells are altered in models of spaceflight. One such animal model is antiorthostatic suspension (AOS), in which the experimental animal is subjected to a head-down tilt that mimics both the stress and the cephalad fluid shift experienced in spaceflight. A previous study reported that the peritoneal neutrophils from mice experiencing AOS generated less superoxide than unsuspended controls. We expanded on this study using several different stimuli and measuring the oxidative response of murine neutrophils in a variety of ways. These responses included the rate, lag period, and dose/response characteristics for superoxide generation, FACS analysis with dihydrodichlorofluorescein as a substrate, and a chemiluminescence response with luminol as a substrate. We also examined phagocytosis of three different microorganisms. While some effects of orthostatic suspension (attributable to the stress of the apparatus) were observed, no clear effects of AOS on oxidative function of the peritoneal neutrophils were seen.

Influence of spaceflight on the production of interleukin-3 and interleukin-6 by rat spleen and thymus cells

NASA Technical Reports Server (NTRS)

Miller, Edwin S.; Koebel, D. Anne; Sonnefeld, Gerald

1995-01-01

Six adult male Sprague-Dawley rats were flown on the 7-day US space shuttle mission STS-54. After flight, the spleen and thymus from each animal were assayed for the capacity to secrete the cytokines interleukin-3 (IL-3) and IL-6. Spleen and thymus cells were incubated for 48 h in the presence of 5 microgram/ml of concanavalin A or 2 microgram/ml of bacterial lipopolysaccharide to stimulate the production of IL-3 and IL-6. IL-3 activity was measured using the IL-3/colony-stimulating-factor-dependent cell line 32D. IL-6 activity was measured using the IL-6-dependent cell line 7TD1. Spleen and thymus cells harvested from flown rats secreted significantly higher titers of biologically active IL-3 compared with ground control rats. Spaceflight significantly enhanced IL-6 production by thymus, but not spleen, cells. The results of this study demonstrate that spaceflight can enhance the production of certain cytokines by cells of the immune system.

The Hindlimb Unloading Rat Model: Literature Overview, Comparison with Spaceflight Data, and Technique Update

NASA Technical Reports Server (NTRS)

Morey-Holton, Emily; Globus, Ruth K.; Kaplansky, Alexander; Durnova, Galina

2004-01-01

The hindlimb unloading (HU) rodent model is used extensively to study the response of many physiological systems to certain aspects of spaceflight, as well as to disuse and recovery from disuse for Earth benefits. This chapter describes the evolution of HU, and is divided into three sections. The first section examines the characteristics of 1063 articles using or reviewing the HU model, published between 1976 and April 1, 2004. The characteristics include number of publications, journals, countries, major physiological systems, method modifications, species, gender, genetic strains and ages of rodents, experiment duration, and countermeasures. The second section provides a comparison of results between space flown and Hu animals from the 14-day Cosmos 2044 mission. The final section describes modifications to HU required by different experimental paradigms and a method to protect the tail harness for long duration studies. HU in rodents has enabled improved understanding of the responses of the musculoskeletal, cardiovascular, immune, renal, neural, metabolic, and reproductive systems to unloading and/or to reloading on Earth with implications for both long-duration human spaceflight and disuse on Earth.

Association of IL-12p70 and IL-6:IL-10 ratio with autism-related behaviors in 22q11.2 deletion syndrome: a preliminary report.

PubMed

Ross, Heather E; Guo, Ying; Coleman, Karlene; Ousley, Opal; Miller, Andrew H

2013-07-01

22q11.2 deletion syndrome (22q11DS) is a genetic disorder that conveys a significant risk for the development of social behavior disorders, including autism and schizophrenia. Also known as DiGeorge syndrome, 22q11DS is the second most common genetic disorder and is characterized by an elevated risk for immune dysfunction, up to 77% of individuals have an identifiable immune deficiency. We hypothesize that this immune dysfunction could contribute to the elevated risk of impaired social behavior seen in 22q11DS. The current study begins to elucidate these immune deficits and link them with the behavioral alterations associated with the disorder. Serum concentrations of a series of cytokines were examined, using a multiplex immunoassay, in sixteen individuals with 22q11DS and screened for autism-related behavior using the Autism Diagnostic Interview-Revised (ADI-R). This preliminary study examined correlations between specific immune proteins and each of the ADI-R algorithm scores (social, communication, and repetitive behavior). The inflammatory cytokine IL-1β, as well as the ratio between the inflammatory cytokine IL-6 and the anti-inflammatory cytokine IL-10, were correlated with social scores (r=0.851, p=0.004; r=0.580, p=0.018). In addition, the inflammatory cytokines interferon gamma and IL-12p70 were correlated with repetitive behaviors (r=0.795, p=0.033; r=0.774, p=0.002). Interestingly, IL-12 has been reported to be increased in autistic children. These data show a positive association between severity of autism-related behaviors and level of serum concentrations of inflammatory cytokines in individuals with 22q11DS, providing a basis for further inquiry. Copyright © 2013 Elsevier Inc. All rights reserved.

Is chronic fatigue syndrome an autoimmune disorder of endogenous neuropeptides, exogenous infection and molecular mimicry?

PubMed

Staines, Donald R

2004-01-01

Chronic fatigue syndrome is a disorder characterised by prolonged fatigue and debility and is mostly associated with post-infection sequelae although ongoing infection is unproven. Immunological aberration is likely and this may prove to be associated with an expanding group of vasoactive neuropeptides in the context of molecular mimicry and inappropriate immunological memory. Vasoactive neuropeptides including vasoactive intestinal peptide (VIP) and pituitary adenylate activating polypeptide (PACAP) belong to the secretin/glucagon superfamily and act as hormones, neurotransmitters, immune modulators and neurotrophes. They are readily catalysed to smaller peptide fragments by antibody hydrolysis. They and their binding sites are immunogenic and are known to be associated with a range of autoimmune conditions. Vasoactive neuropeptides are widely distributed in the body particularly in the central, autonomic and peripheral nervous systems and have been identified in the gut, adrenal gland, reproductive organs, vasculature, blood cells and other tissues. They have a vital role in maintaining vascular flow in organs, and in thermoregulation, memory and concentration. They are co-transmitters for acetylcholine, nitric oxide, endogenous opioids and insulin, are potent immune regulators with primarily anti-inflammatory activity, and have a significant role in protection of the nervous system to toxic assault, promotion of neural development and the maintenance of homeostasis. This paper describes a biologically plausible mechanism for the development of CFS based on loss of immunological tolerance to the vasoactive neuropeptides following infection, significant physical exercise or de novo. It is proposed that release of these substances is accompanied by a loss of tolerance either to them or their receptor binding sites in CFS. Such an occurrence would have predictably serious consequences resulting from compromised function of the key roles these substances perform. All documented symptoms of CFS are explained by vasoactive neuropeptide compromise, namely fatigue and nervous system dysfunction through impaired acetylcholine activity, myalgia through nitric oxide and endogenous opioid dysfunction, chemical sensitivity through peroxynitrite and adenosine dysfunction, and immunological disturbance through changes in immune modulation. Perverse immunological memory established against these substances or their receptors may be the reason for the protracted nature of this condition. The novel status of these substances together with their extremely small concentrations in blood and tissues means that clinical research into them is still in its infancy. A biologically plausible theory of CFS causation associated with vasoactive neuropeptide dysfunction would promote a coherent and systematic approach to research into this and other possibly associated disabling conditions.

Infectious Disease risks associated with exposure to stressful environments

NASA Technical Reports Server (NTRS)

Meehan, Ichard T.; Smith, Morey; Sams, Clarence

1993-01-01

Multiple environmental factors asociated with space flight can increase the risk of infectious illness among crewmembers thereby adversely affecting crew health and mission success. Host defences can be impaired by multiple physiological and psychological stressors including: sleep deprivation, disrupted circadian rhythms, separation from family, perceived danger, radiation exposure, and possibly also by the direct and indirect effects of microgravity. Relevant human immunological data from isolated or stressful environments including spaceflight will be reviewed. Long-duration missions should include reliable hardware which supports sophisticated immunodiagnostic capabilities. Future advances in immunology and molecular biology will continue to provide therapeutic agents and biologic response modifiers which should effectively and selectively restore immune function which has been depressed by exposure to environmental stressors.

Effects of spaceflight on the immunoglobulin repertoire of unimmunized C57BL/6 mice

NASA Astrophysics Data System (ADS)

Ward, Claire; Rettig, Trisha A.; Hlavacek, Savannah; Bye, Bailey A.; Pecaut, Michael J.; Chapes, Stephen K.

2018-02-01

Spaceflight has been shown to suppress the adaptive immune response, altering the distribution and function of lymphocyte populations. B lymphocytes express highly specific and highly diversified receptors, known as immunoglobulins (Ig), that directly bind and neutralize pathogens. Ig diversity is achieved through the enzymatic splicing of gene segments within the genomic DNA of each B cell in a host. The collection of Ig specificities within a host, or Ig repertoire, has been increasingly characterized in both basic research and clinical settings using high-throughput sequencing technology (HTS). We utilized HTS to test the hypothesis that spaceflight affects the B-cell repertoire. To test this hypothesis, we characterized the impact of spaceflight on the unimmunized Ig repertoire of C57BL/6 mice that were flown aboard the International Space Station (ISS) during the Rodent Research One validation flight in comparison to ground controls. Individual gene segment usage was similar between ground control and flight animals, however, gene segment combinations and the junctions in which gene segments combine was varied among animals within and between treatment groups. We also found that spontaneous somatic mutations in the IgH and Igκ gene loci were not increased. These data suggest that space flight did not affect the B cell repertoire of mice flown and housed on the ISS over a short period of time.

Evidence Report: Risk of Spaceflight Associated Neuro-ocular Syndrome (SANS)

NASA Technical Reports Server (NTRS)

Stenger, Michael B.; Tarver, William J.; Brunstetter, Tyson; Gibson, Charles Robert; Laurie, Steven S.; Lee, Stuart M. C.; Macias, Brandon R.; Mader, Thomas H.; Otto, Christian; Smith, Scott M.;

Metabolic regulation of inflammation.

PubMed

Gaber, Timo; Strehl, Cindy; Buttgereit, Frank

2017-05-01

Immune cells constantly patrol the body via the bloodstream and migrate into multiple tissues where they face variable and sometimes demanding environmental conditions. Nutrient and oxygen availability can vary during homeostasis, and especially during the course of an immune response, creating a demand for immune cells that are highly metabolically dynamic. As an evolutionary response, immune cells have developed different metabolic programmes to supply them with cellular energy and biomolecules, enabling them to cope with changing and challenging metabolic conditions. In the past 5 years, it has become clear that cellular metabolism affects immune cell function and differentiation, and that disease-specific metabolic configurations might provide an explanation for the dysfunctional immune responses seen in rheumatic diseases. This Review outlines the metabolic challenges faced by immune cells in states of homeostasis and inflammation, as well as the variety of metabolic configurations utilized by immune cells during differentiation and activation. Changes in cellular metabolism that contribute towards the dysfunctional immune responses seen in rheumatic diseases are also briefly discussed.

Cytotoxic immune responses in the lungs correlate to disease severity in patients with hantavirus infection.

PubMed

Rasmuson, J; Pourazar, J; Mohamed, N; Lejon, K; Evander, M; Blomberg, A; Ahlm, C

2016-04-01

Hantavirus infections may cause severe and sometime life-threatening lung failure. The pathogenesis is not fully known and there is an urgent need for effective treatment. We aimed to investigate the association between pulmonary viral load and immune responses, and their relation to disease severity. Bronchoscopy with sampling of bronchoalveolar lavage (BAL) fluid was performed in 17 patients with acute Puumala hantavirus infection and 16 healthy volunteers acting as controls. Lymphocyte subsets, granzyme concentrations, and viral load were determined by flow cytometry, enzyme-linked immunosorbent assay (ELISA), and quantitative reverse transcription polymerase chain reaction (RT-PCR), respectively. Analyses of BAL fluid revealed significantly higher numbers of activated CD8(+) T cells and natural killer (NK) cells, as well as higher concentrations of the cytotoxins granzymes A and B in hantavirus-infected patients, compared to controls. In patients, Puumala hantavirus RNA was detected in 88 % of BAL cell samples and correlated inversely to the T cell response. The magnitude of the pulmonary cytotoxic lymphocyte response correlated to the severity of disease and systemic organ dysfunction, in terms of need for supplemental oxygen treatment, hypotension, and laboratory data indicating renal failure, cardiac dysfunction, vascular leakage, and cell damage. Regulatory T cell numbers were significantly lower in patients compared to controls, and may reflect inadequate immune regulation during hantavirus infection. Hantavirus infection elicits a pronounced cytotoxic lymphocyte response in the lungs. The magnitude of the immune response was associated with disease severity. These results give insights into the pathogenesis and possibilities for new treatments.

Study protocol to examine the effects of spaceflight and a spaceflight analog on neurocognitive performance: extent, longevity, and neural bases.

PubMed

Koppelmans, Vincent; Erdeniz, Burak; De Dios, Yiri E; Wood, Scott J; Reuter-Lorenz, Patricia A; Kofman, Igor; Bloomberg, Jacob J; Mulavara, Ajitkumar P; Seidler, Rachael D

2013-12-18

Long duration spaceflight (i.e., 22 days or longer) has been associated with changes in sensorimotor systems, resulting in difficulties that astronauts experience with posture control, locomotion, and manual control. The microgravity environment is an important causal factor for spaceflight induced sensorimotor changes. Whether spaceflight also affects other central nervous system functions such as cognition is yet largely unknown, but of importance in consideration of the health and performance of crewmembers both in- and post-flight. We are therefore conducting a controlled prospective longitudinal study to investigate the effects of spaceflight on the extent, longevity and neural bases of sensorimotor and cognitive performance changes. Here we present the protocol of our study. This study includes three groups (astronauts, bed rest subjects, ground-based control subjects) for which each the design is single group with repeated measures. The effects of spaceflight on the brain will be investigated in astronauts who will be assessed at two time points pre-, at three time points during-, and at four time points following a spaceflight mission of six months. To parse out the effect of microgravity from the overall effects of spaceflight, we investigate the effects of seventy days head-down tilted bed rest. Bed rest subjects will be assessed at two time points before-, two time points during-, and three time points post-bed rest. A third group of ground based controls will be measured at four time points to assess reliability of our measures over time. For all participants and at all time points, except in flight, measures of neurocognitive performance, fine motor control, gait, balance, structural MRI (T1, DTI), task fMRI, and functional connectivity MRI will be obtained. In flight, astronauts will complete some of the tasks that they complete pre- and post flight, including tasks measuring spatial working memory, sensorimotor adaptation, and fine motor performance. Potential changes over time and associations between cognition, motor-behavior, and brain structure and function will be analyzed. This study explores how spaceflight induced brain changes impact functional performance. This understanding could aid in the design of targeted countermeasures to mitigate the negative effects of long-duration spaceflight.

Media Ion Composition Controls Regulatory and Virulence Response of Salmonella in Spaceflight

PubMed Central

Wilson, James W.; Ott, C. Mark; Quick, Laura; Davis, Richard; zu Bentrup, Kerstin Höner; Crabbé, Aurélie; Richter, Emily; Sarker, Shameema; Barrila, Jennifer; Porwollik, Steffen; Cheng, Pui; McClelland, Michael; Tsaprailis, George; Radabaugh, Timothy; Hunt, Andrea; Shah, Miti; Nelman-Gonzalez, Mayra; Hing, Steve; Parra, Macarena; Dumars, Paula; Norwood, Kelly; Bober, Ramona; Devich, Jennifer; Ruggles, Ashleigh; CdeBaca, Autumn; Narayan, Satro; Benjamin, Joseph; Goulart, Carla; Rupert, Mark; Catella, Luke; Schurr, Michael J.; Buchanan, Kent; Morici, Lisa; McCracken, James; Porter, Marc D.; Pierson, Duane L.; Smith, Scott M.; Mergeay, Max; Leys, Natalie; Stefanyshyn-Piper, Heidemarie M.; Gorie, Dominic; Nickerson, Cheryl A.

2008-01-01

The spaceflight environment is relevant to conditions encountered by pathogens during the course of infection and induces novel changes in microbial pathogenesis not observed using conventional methods. It is unclear how microbial cells sense spaceflight-associated changes to their growth environment and orchestrate corresponding changes in molecular and physiological phenotypes relevant to the infection process. Here we report that spaceflight-induced increases in Salmonella virulence are regulated by media ion composition, and that phosphate ion is sufficient to alter related pathogenesis responses in a spaceflight analogue model. Using whole genome microarray and proteomic analyses from two independent Space Shuttle missions, we identified evolutionarily conserved molecular pathways in Salmonella that respond to spaceflight under all media compositions tested. Identification of conserved regulatory paradigms opens new avenues to control microbial responses during the infection process and holds promise to provide an improved understanding of human health and disease on Earth. PMID:19079590

Host-Microbe Interactions in Microgravity: Assessment and Implications

PubMed Central

Foster, Jamie S.; Wheeler, Raymond M.; Pamphile, Regine

2014-01-01

Spaceflight imposes several unique stresses on biological life that together can have a profound impact on the homeostasis between eukaryotes and their associated microbes. One such stressor, microgravity, has been shown to alter host-microbe interactions at the genetic and physiological levels. Recent sequencing of the microbiomes associated with plants and animals have shown that these interactions are essential for maintaining host health through the regulation of several metabolic and immune responses. Disruptions to various environmental parameters or community characteristics may impact the resiliency of the microbiome, thus potentially driving host-microbe associations towards disease. In this review, we discuss our current understanding of host-microbe interactions in microgravity and assess the impact of this unique environmental stress on the normal physiological and genetic responses of both pathogenic and mutualistic associations. As humans move beyond our biosphere and undergo longer duration space flights, it will be essential to more fully understand microbial fitness in microgravity conditions in order to maintain a healthy homeostasis between humans, plants and their respective microbiomes. PMID:25370197

Host-microbe interactions in microgravity: assessment and implications.

PubMed

Foster, Jamie S; Wheeler, Raymond M; Pamphile, Regine

2014-05-26

Spaceflight imposes several unique stresses on biological life that together can have a profound impact on the homeostasis between eukaryotes and their associated microbes. One such stressor, microgravity, has been shown to alter host-microbe interactions at the genetic and physiological levels. Recent sequencing of the microbiomes associated with plants and animals have shown that these interactions are essential for maintaining host health through the regulation of several metabolic and immune responses. Disruptions to various environmental parameters or community characteristics may impact the resiliency of the microbiome, thus potentially driving host-microbe associations towards disease. In this review, we discuss our current understanding of host-microbe interactions in microgravity and assess the impact of this unique environmental stress on the normal physiological and genetic responses of both pathogenic and mutualistic associations. As humans move beyond our biosphere and undergo longer duration space flights, it will be essential to more fully understand microbial fitness in microgravity conditions in order to maintain a healthy homeostasis between humans, plants and their respective microbiomes.

Carotid Intima Media Thickness in the Astronaut Corps: Association to Spacecraft

NASA Technical Reports Server (NTRS)

Suffredini, John; Locke, James; Johnston, Smith; Charvat, Jacqueline; Young, Millennia; Garcia, Kathleen; Sargsyan, Ashot E.; Tarver, William

2017-01-01

Background: Carotid Intima Media Thickness (CIMT) has been demonstrated to be predictive of future cardiovascular events. Within various populations, radiation exposure, stress, and physical confinement have all been linked to an increased CIMT. Recent research discovered CIMT was significantly increased in ten long duration astronauts from pre-flight to four days post flight. The relationship between spaceflight and CIMT is not understood and trends in CIMT within the larger astronaut population are unknown. Methods: In 2010, CIMT was offered as part of the astronaut annual exam at the JSC Flight Medicine Clinic using a standardized CIMT screening protocol and professional sonographers. Between 2010 and 2016, CIMT measurements were collected on 213 NASA astronauts and payload specialists. The values used in this retrospective chart review are the mean of the CIMT from the right and left. Spaceflight exposure was categorized based on the total number of days spent in space at the time of the ground-based ultrasound (0, 1-29, 30-100, 101-200, =200). Linear regression with generalized estimating equations were used to estimate the association between spaceflight exposures and CIMT. Results: 530 studies were completed among 213 astronauts with a mean of 2.5 studies (range 1-6) per astronaut over the six year period. As in other populations, CIMT was significantly associated with age; however, gender was not. While there was no significant direct correlation between total spaceflight exposure and CIMT found, astronauts with 30-100 spaceflight days and astronauts with greater than 100 spaceflight days had significantly increased CIMT over astronauts who had never flown (p=0.002 and p=<0.0001 respectively) after adjustment for age. Conclusion: Further work is needed to fully understand CIMT and its association to spaceflight. Current occupational surveillance activities are under way to study CIMT values in conjunction with other cardiovascular risk factors among astronauts as compared to the general population.

Response of Lactobacillus acidophilus ATCC 4356 to low-shear modeled microgravity

NASA Astrophysics Data System (ADS)

Castro-Wallace, Sarah; Stahl, Sarah; Voorhies, Alexander; Lorenzi, Hernan; Douglas, Grace L.

2017-10-01

The introduction of probiotic microbes into the spaceflight food system has the potential for use as a safe, non-invasive, daily countermeasure to crew microbiome and immune dysregulation. However, the microgravity effects on the stress tolerances and gene expression of probiotic bacteria must be investigated to confirm that benefits of selected strains will still be conveyed under microgravity conditions. The goal of this study was to evaluate the characteristics of the probiotic bacteria Lactobacillus acidophilus ATCC 4356 in a microgravity analog environment. L. acidophilus was cultured anaerobically under modeled microgravity conditions and assessed for differences in growth, survival through stress challenge, and gene expression compared to control cultures. No significant differences were observed between the modeled microgravity and control grown L. acidophilus, suggesting that this strain will behave similarly in spaceflight.

Human mononuclear cell function after 4 C storage during 1-G and microgravity conditions of spaceflight

NASA Technical Reports Server (NTRS)

Meehan, Richard; Taylor, Gerald; Lionetti, Fabian; Neale, Laurie; Curren, Tim

1989-01-01

To investigate the possibility of restoring immune competence of crewmembers during a prolonged spaceflight by infusions of autologous blood components, the effect of storage at 4 C aboard Space Shuttle Columbia (Mission 61-c) on the activity of human peripheral blood mononuclear cells (PBMNCs), stored as leukocyte concentrates in autologous plasa, was investigated. The results of preflight storage at 4 C demonstrated a progressive daily loss in mitogen-stimulated protein synthesis, and thymidine uptake, as well as a progressive reduction in the percentage of PBMNCs expressing cell-surface phenotype markers. The ability of PBMNCs stored at 4 C for 8 d in Columbia's middeck, to become activated and proliferate in vitro was similar to that of cells that remained for 7 d on ground.

Neuroendocrine and Immune System Responses with Spaceflights

NASA Technical Reports Server (NTRS)

Tipton, Charles M.; Greenleaf, John E.; Jackson, Catherine G. R.

1996-01-01

Despite the fact that the first human was in space during 1961 and individuals have existed in a microgravity environment for more than a year, there are limited spaceflight data available on the responses of the neuroendocrine and immune systems. Because of mutual interactions between these respective integrative systems, it is inappropriate to assume that the responses of one have no impact on functions of the other. Blood and plasma volume consistently decrease with spaceflight; hence, blood endocrine and immune constituents will be modified by both gravitational and measurement influences. The majority of the in-flight data relates to endocrine responses that influence fluids and electrolytes during the first month in space. Adrenocorticotropin (ACTH), aldo-sterone. and anti-diuretic hormone (ADH) appear to be elevated with little change in the atrial natriuretic peptides (ANP). Flight results longer than 60 d show increased ADH variability with elevations in angiotensin and cortisol. Although post-flight results are influenced by reentry and recovery events, ACTH and ADH appear to be consistently elevated with variable results being reported for the other hormones. Limited in-flight data on insulin and growth hormone levels suggest they are not elevated to counteract the loss in muscle mass. Post-flight results from short- and long-term flights indicate that thyroxine and insulin are increased while growth hormone exhibits minimal change. In-flight parathyroid hormone (PTH) levels are variable for several weeks after which they remain elevated. Post-flight PTH was increased on missions that lasted either 7 or 237 d, whereas calcitonin concentrations were increased after 1 wk but decreased after longer flights. Leukocytes are elevated in flights of various durations because of an increase in neutrophils. The majority of post-flight data indicates immunoglobulin concentrations are not significantly changed from pre-flight measurements. However, the numbers of T-lymphocytes and natural killer cells are decreased with post-flight conditions. Of the lymphokines, interleukin-2 production, lymphocyte responsiveness, and the activity of natural killer cells are consistently reduced post-flight. Limited head-down tilt (HDT) data suggest it is an effective simulation model for microgravity investigations. Neuroendocrine and pharmacological countermeasures are virtually nonexistent arid should become high priority items for future research. Although exercise has the potential to be an effective countermeasure for various neuroen-docrine-immune responses in microgravity, this concept must be tested before flights to Mars are scheduled.

Immune System Dysregulation and Herpesvirus Reactivation Persist During Long-Duration Spaceflight

NASA Technical Reports Server (NTRS)

Crucian, B. E.; Stowe, R. P.; Mehta, S.; Uchakin, P.; Quiriarte, H.; Pierson, D.; Sams, C. F.

2010-01-01

Background: Immunity, latent herpesvirus reactivation, physiological stress and circadian rhythms were assessed during six month spaceflight onboard ISS. Blood and saliva samples were collected early, mid and late in-flight and returned for immediate analysis. Mid-point study data (10 of 17 planned subjects) will be presented. Results: Some shifts in leukocyte distribution occurred during flight, including alterations in CD8+ T cell maturation. General T cell function was consistently reduced early in-flight. Levels CD8+/IFNg+ producing T cells were depressed early in-flight, and immediately upon landing. Persistent mitogen-dependant reductions were observed in IFNg, IL-17a, IL-10, TNFa and IL-6 production. Monocyte production of IL-10 was reduced, whereas IL-8 levels were increased. Levels of mRNA for the TNFa, IL-6 and IFNg were transiently elevated early in-flight, and the dynamics of TNF and IL-6 gene expression were somewhat antagonistic to their corresponding receptors during flight. The number of virus-specific CD8+ T-cells was measured using MHC tetramers, while their function was measured using intracellular cytokine analysis following peptide stimulation. Both the number and function of EBV-specific cells decreased during flight as compared to preflight levels. The number of CMV-specific T-cells generally increased as the mission progressed while their function was variable. Viral (EBV) load in blood was elevated postflight. Anti-EBV VCA antibodies were significantly elevated by R+0; anti-EA antibodies were not significantly elevated at landing; and anti-CMV antibodies were somewhat elevated during flight. Higher levels of salivary EBV DNA were found during flight. VZV DNA reactivation occurred in 50 % of astronauts during flight, continuing for up to 30 days post-flight. CMV was shed in 35 % the in-flight and 30% of postflight urine samples of the crewmembers. There was generally a higher level of cortisol as measured in urine and saliva in the astronauts during flight, but plasma cortisol was relatively unchanged during flight. Circadian rhythm of salivary cortisol was altered during flight. Conclusion. Some alterations in immunity do not resolve during six month spaceflight, consequentially resulting in persistent herpesvirus reactivation. Ongoing immune dysregulation may represent specific clinical risks for exploration-class space missions.

Effects of 17-day spaceflight on knee extensor muscle function and size

NASA Technical Reports Server (NTRS)

Tesch, Per A.; Berg, Hans E.; Bring, Daniel; Evans, Harlan J.; LeBlanc, Adrian D.

2005-01-01

It is generally held that space travelers experience muscle dysfunction and atrophy during exposure to microgravity. However, observations are scarce and reports somewhat inconsistent with regard to the time course, specificity and magnitude of such changes. Hence, we examined four male astronauts (group mean approximately 43 years, 86 kg and 183 cm) before and after a 17-day spaceflight (Space Transport System-78). Knee extensor muscle function was measured during maximal bilateral voluntary isometric and iso-inertial concentric, and eccentric actions. Cross-sectional area (CSA) of the knee extensor and flexor, and gluteal muscle groups was assessed by means of magnetic resonance imaging. The decrease in strength (P<0.05) across different muscle actions after spaceflight amounted to 10%. Eight ambulatory men, examined on two occasions 20 days apart, showed unchanged (P>0.05) muscle strength. CSA of the knee extensor and gluteal muscles, each decreased (P<0.05) by 8%. Knee flexor muscle CSA showed no significant (P>0.05) change. The magnitude of these changes concord with earlier results from ground-based studies of similar duration. The results of this study, however, do contrast with the findings of no decrease in maximal voluntary ankle plantar flexor force previously reported in the same crew.

MicroRNA-155 attenuates late sepsis-induced cardiac dysfunction through JNK and β-arrestin 2.

PubMed

Zhou, Yu; Song, Yan; Shaikh, Zahir; Li, Hui; Zhang, Haiju; Caudle, Yi; Zheng, Shouhua; Yan, Hui; Hu, Dan; Stuart, Charles; Yin, Deling

2017-07-18

Cardiac dysfunction is correlated with detrimental prognosis of sepsis and contributes to a high risk of mortality. After an initial hyperinflammatory reaction, most patients enter a protracted state of immunosuppression (late sepsis) that alters both innate and adaptive immunity. The changes of cardiac function in late sepsis are not yet known. MicroRNA-155 (miR-155) is previously found to play important roles in both regulations of immune activation and cardiac function. In this study, C57BL/6 mice were operated to develop into early and late sepsis phases, and miR-155 mimic was injected through the tail vein 48 h after cecal ligation and puncture (CLP). The effect of miR-155 on CLP-induced cardiac dysfunction was explored in late sepsis. We found that increased expression of miR-155 in the myocardium protected against cardiac dysfunction in late sepsis evidenced by attenuating sepsis-reduced cardiac output and enhancing left ventricular systolic function. We also observed that miR-155 markedly reduced the infiltration of macrophages and neutrophils into the myocardium and attenuated the inflammatory response via suppression of JNK signaling pathway. Moreover, overexpression of β-arrestin 2 (Arrb2) exacerbated the mice mortality and immunosuppression in late sepsis. Furthermore, transfection of miR-155 mimic reduced Arrb2 expression, and then restored immunocompetence and improved survival in late septic mice. We conclude that increased miR-155 expression through systemic administration of miR-155 mimic attenuates cardiac dysfunction and improves late sepsis survival by targeting JNK associated inflammatory signaling and Arrb2 mediated immunosuppression.

Nephrotoxicity of Natural Products.

PubMed

Nauffal, Mary; Gabardi, Steven

2016-01-01

The manufacture and sale of natural products constitute a multi-billion dollar industry. Nearly a third of the American population admit to using some form of complementary or alternative medicine, with many using them in addition to prescription medications. Most patients fail to inform their healthcare providers of their natural product use and physicians rarely inquire. Annually, thousands of natural product-induced adverse events are reported to Poison Control Centers nationwide. Natural product manufacturers are not responsible for proving safety and efficacy, as the FDA does not regulate them. However, concerns exist surrounding the safety of natural products. This review provides details on natural products that have been associated with renal dysfunction. We have focused on products that have been associated with direct renal injury, immune-mediated nephrotoxicity, nephrolithiasis, rhabdomyolysis with acute renal injury, hepatorenal syndrome, and common adulterants or contaminants that are associated with renal dysfunction. The potential for natural products to cause renal dysfunction is justifiable. It is imperative that natural product use be monitored closely in all patients. Healthcare practitioners must play an active role in identifying patients using natural products and provide appropriate patient education. © 2016 S. Karger AG, Basel.

Nutritional support to maintain proper immune status during intense training.

PubMed

Gleeson, Michael

2013-01-01

Prolonged exercise and heavy training are associated with depressed immune function which can increase the risk of picking up minor infections. To maintain robust immunity, athletes should eat a well-balanced diet sufficient to meet their energy, carbohydrate, protein, and micronutrient requirements. Dietary deficiencies of protein and specific micronutrients have long been associated with immune dysfunction and an adequate intake of iron, zinc, and vitamins A, D, E, B6 and B12 is particularly important in the maintenance of immune function. Consuming carbohydrate during prolonged strenuous exercise attenuates rises in stress hormones and appears to limit the degree of exercise-induced immune depression. Similar effects can be seen with daily ingestion of high-dose antioxidant vitamin supplements, though concerns have been expressed that excessive antioxidant intake may impair exercise training adaptations. It is safe to say with reasonable confidence that individual amino acids, colostrum, Echinacea, and zinc are unlikely to boost immunity or reduce infection risk in athletes. The ingestion of carbohydrate during exercise and daily consumption of probiotic and plant polyphenol (e.g. quercetin)-containing supplements or foodstuffs (e.g. non-alcoholic beer) currently offer the best chance of success. This approach is likely to be most effective for individuals who are particularly prone to illness. Copyright © 2013 Nestec Ltd., Vevey/S. Karger AG, Basel.

Adipose tissue immunity and cancer

PubMed Central

Catalán, Victoria; Gómez-Ambrosi, Javier; Rodríguez, Amaia; Frühbeck, Gema

2013-01-01

Inflammation and altered immune response are important components of obesity and contribute greatly to the promotion of obesity-related metabolic complications, especially cancer development. Adipose tissue expansion is associated with increased infiltration of various types of immune cells from both the innate and adaptive immune systems. Thus, adipocytes and infiltrating immune cells secrete pro-inflammatory adipokines and cytokines providing a microenvironment favorable for tumor growth. Accumulation of B and T cells in adipose tissue precedes macrophage infiltration causing a chronic low-grade inflammation. Phenotypic switching toward M1 macrophages and Th1 T cells constitutes an important mechanism described in the obese state correlating with increased tumor growth risk. Other possible synergic mechanisms causing a dysfunctional adipose tissue include fatty acid-induced inflammation, oxidative stress, endoplasmic reticulum stress, and hypoxia. Recent investigations have started to unravel the intricacy of the cross-talk between tumor cell/immune cell/adipocyte. In this sense, future therapies should take into account the combination of anti-inflammatory approaches that target the tumor microenvironment with more sophisticated and selective anti-tumoral drugs. PMID:24106481

The albumin-bilirubin grade uncovers the prognostic relationship between hepatic reserve and immune dysfunction in HIV-associated hepatocellular carcinoma.

PubMed

Pinato, D J; Sharma, R; Citti, C; Platt, H; Ventura-Cots, M; Allara, E; Chen, T-Y; Dalla Pria, A; Jain, M; Mínguez, B; Kikuchi, L; Kaufman West, E; Merli, M; Kaplan, D E; Hasson, H; Marks, K; Nelson, M; Núñez, M; Aytaman, A; Bower, M; Bräu, N

2018-01-01

Hepatocellular carcinoma (HCC) is a leading cause of liver-related mortality in people living with HIV, where co-infection with hepatotropic viruses accelerates the course of chronic liver disease. To evaluate whether the albumin-bilirubin (ALBI) grade, a more accurate marker of liver dysfunction in HCC, might identify patients with progressive liver dysfunction in the context of HIV/hepatitis co-infection. Using uni- and multi-variable analyses, we studied the albumin-bilirubin grade as a predictor of overall survival (OS) in a large, multi-center cohort of patients with HIV-associated HCC recruited from 44 centres in 9 countries within the Liver Cancer in HIV study group. Patients who underwent liver transplantation were excluded. A total of 387 patients, predominantly HCV co-infected (78%) with balanced representation of all Barcelona Clinic Liver Cancer (BCLC) stages (A = 33%, B = 18%, C = 37%, D = 12%) were recruited. At HCC diagnosis, 84% had been on anti-retrovirals for a median duration of 8.8 years. The albumin-bilirubin grade identified significant differences in median survival of 97 months for grade 1 (95% CI 13-180 months), 17 months for grade 2 (95% CI 11-22 months) and 6 months for grade 3 (95% CI 4-9 months, P < .001). A more advanced albumin-bilirubin grade correlated with lower CD4 counts (464/373/288 cells/mm 3 for grades 1/2/3) and higher HIV viraemia (3.337/8.701/61.845 copies/mL for grades 1/2/3, P < .001). In this large, multi-center retrospective study, the albumin-bilirubin grade highlights the interplay between liver reserve and immune dysfunction as prognostic determinants in HIV-associated HCC. © 2017 John Wiley & Sons Ltd.

Autoimmunity in the pathogenesis and treatment of keratoconjunctivitis sicca.

PubMed

Liu, Katy C; Huynh, Kyle; Grubbs, Joseph; Davis, Richard M

2014-01-01

Dry eye is a chronic corneal disease that impacts the quality of life of many older adults. Keratoconjunctivitis sicca (KCS), a form of aqueous-deficient dry eye, is frequently associated with Sjögren's syndrome and mechanisms of autoimmunity. For KCS and other forms of dry eye, current treatments are limited, with many medications providing only symptomatic relief rather than targeting the pathophysiology of disease. Here, we review proposed mechanisms in the pathogenesis of autoimmune-based KCS: genetic susceptibility and disruptions in antigen recognition, immune response, and immune regulation. By understanding the mechanisms of immune dysfunction through basic science and translational research, potential drug targets can be identified. Finally, we discuss current dry eye therapies as well as promising new treatment options and drug therapy targets.

T-cell immunity and cytokine production in cosmonauts after long-duration space flights

NASA Astrophysics Data System (ADS)

Morukov, B.; Rykova, M.; Antropova, E.; Berendeeva, T.; Ponomaryov, S.; Larina, I.

2011-04-01

Long-duration spaceflight effects on T-cell immunity and cytokine production were studied in 12 Russian cosmonauts flown onto the International Space Station. Specific assays were performed before launch and after landing and included analysis of peripheral leukocyte distribution, analysis of T-cell phenotype, expression of activation markers, apoptosis, proliferation of T cells in response to a mitogen, concentrations of cytokines in supernatants of cell cultures. Statistically significant increase was observed in leukocytes', lymphocytes', monocytes' and granulocytes' total number, increase in percentage and absolutely number of CD3 +CD4 +-cells, CD4 +CD45RA +-cells and CD4 +CD45RA +/CD4 +CD45RО + ratio, CD4 +CD25 +Bright regulatory cells ( p<0,05) in peripheral blood after landing. T-lymphocytes' capacity to present CD69 and CD25 on its own surfaces was increased for the majority of crewmembers. Analysis of T-cell response to PHA-stimulation in vitro revealed there were some trends toward reduced proliferation of stimulated T-lymphocytes. There was an apparent post flight decrease in secreted IFN-g for the majority of crewmembers and in most instances there was elevation in secreted IL-10. It revealed depression of IFN-g/IL-10 ratio after flight. Correlation analysis according to Spearman's rank correlation test established significant positive correlations ( p<0.05) between cytokine production and T-cell activation (CD25+, CD38+) and negative correlation ( p<0.05) between cytokine production and number of bulk memory CD4+T-cells (CD45RO+). Thus, these results suggest that T-cell dysfunction can be conditioned by cytokine dysbalance and could lead to development of disease after long-duration space flights.

The Environment-Immune Route to Chronic Disease

EPA Science Inventory

Specific environmental factors including chemicals, drugs, microbes and both physical and psychological factors can affect the immune system producing dysfunction and, ultimately, an increased risk ofchronic disease. Several different types of immune alterations can result from e...

Cytosolic nucleic acid sensors and innate immune regulation.

PubMed

Ori, Daisuke; Murase, Motoya; Kawai, Taro

2017-03-04

During viral and bacterial infections, pathogen-derived cytosolic nucleic acids are recognized by the intracellular RNA sensors retinoic acid-inducible gene I and melanoma-differentiated gene 5 and intracellular DNA sensors, including cyclic-di-GMP-AMP synthase, absent in melanoma 2, interferon (IFN)-gamma inducible protein 16, polymerase III, and so on. Binding of intracellular nucleic acids to these sensors activates downstream signaling cascades, resulting in the production of type I IFNs and pro-inflammatory cytokines to induce appropriate systematic immune responses. While these sensors also recognize endogenous nucleic acids and activate immune responses, they can discriminate between self- and non-self-nucleic acids. However, dysfunction of these sensors or failure of regulatory mechanisms causes aberrant activation of immune response and autoimmune disorders. In this review, we focus on how intracellular immune sensors recognize exogenous nucleic acids and activate the innate immune system, and furthermore, how autoimmune diseases result from dysfunction of these sensors.

Effects of Mycotoxins on Mucosal Microbial Infection and Related Pathogenesis

PubMed Central

Park, Seong-Hwan; Kim, Dongwook; Kim, Juil; Moon, Yuseok

2015-01-01

Mycotoxins are fungal secondary metabolites detected in many agricultural commodities and water-damaged indoor environments. Susceptibility to mucosal infectious diseases is closely associated with immune dysfunction caused by mycotoxin exposure in humans and other animals. Many mycotoxins suppress immune function by decreasing the proliferation of activated lymphocytes, impairing phagocytic function of macrophages, and suppressing cytokine production, but some induce hypersensitive responses in different dose regimes. The present review describes various mycotoxin responses to infectious pathogens that trigger mucosa-associated diseases in the gastrointestinal and respiratory tracts of humans and other animals. In particular, it focuses on the effects of mycotoxin exposure on invasion, pathogen clearance, the production of cytokines and immunoglobulins, and the prognostic implications of interactions between infectious pathogens and mycotoxin exposure. PMID:26529017

Chronic Lung Allograft Dysfunction: A Systematic Review of Mechanisms.

PubMed

Royer, Pierre-Joseph; Olivera-Botello, Gustavo; Koutsokera, Angela; Aubert, John-David; Bernasconi, Eric; Tissot, Adrien; Pison, Christophe; Nicod, Laurent; Boissel, Jean-Pierre; Magnan, Antoine

2016-09-01

Chronic lung allograft dysfunction (CLAD) is the major limitation of long-term survival after lung transplantation. Chronic lung allograft dysfunction manifests as bronchiolitis obliterans syndrome or the recently described restrictive allograft syndrome. Although numerous risk factors have been identified so far, the physiopathological mechanisms of CLAD remain poorly understood. We investigate here the immune mechanisms involved in the development of CLAD after lung transplantation. We explore the innate or adaptive immune reactions induced by the allograft itself or by the environment and how they lead to allograft dysfunction. Because current literature suggests bronchiolitis obliterans syndrome and restrictive allograft syndrome as 2 distinct entities, we focus on the specific factors behind one or the other syndromes. Chronic lung allograft dysfunction is a multifactorial disease that remains irreversible and unpredictable so far. We thus finally discuss the potential of systems-biology approach to predict its occurrence and to better understand its underlying mechanisms.

Inflammation, aging, and cancer: tumoricidal versus tumorigenesis of immunity: a common denominator mapping chronic diseases.

PubMed

Khatami, Mahin

2009-01-01

Acute inflammation is a highly regulated defense mechanism of immune system possessing two well-balanced and biologically opposing arms termed apoptosis ('Yin') and wound healing ('Yang') processes. Unresolved or chronic inflammation (oxidative stress) is perhaps the loss of balance between 'Yin' and 'Yang' that would induce co-expression of exaggerated or 'mismatched' apoptotic and wound healing factors in the microenvironment of tissues ('immune meltdown'). Unresolved inflammation could initiate the genesis of many age-associated chronic illnesses such as autoimmune and neurodegenerative diseases or tumors/cancers. In this perspective 'birds' eye' view of major interrelated co-morbidity risk factors that participate in biological shifts of growth-arresting ('tumoricidal') or growth-promoting ('tumorigenic') properties of immune cells and the genesis of chronic inflammatory diseases and cancer will be discussed. Persistent inflammation is perhaps a common denominator in the genesis of nearly all age-associated health problems or cancer. Future challenging opportunities for diagnosis, prevention, and/or therapy of chronic illnesses will require an integrated understanding and identification of developmental phases of inflammation-induced immune dysfunction and age-associated hormonal and physiological readjustments of organ systems. Designing suitable cohort studies to establish the oxido-redox status of adults may prove to be an effective strategy in assessing individual's health toward developing personal medicine for healthy aging.

Cerebrovascular Complications of Diabetes: Focus on Cognitive Dysfunction

PubMed Central

Hardigan, Trevor; Ward, Rebecca; Ergul, Adviye

2017-01-01

The incidence of diabetes has more than doubled in the United States in the last 30 years and the global disease rate is projected to double by 2030. Cognitive impairment has been associated with diabetes, worsening quality of life in patients. The structural and functional interaction of neurons with the surrounding vasculature is critical for proper function of the central nervous system including domains involved in learning and memory. Thus, in this review we explore cognitive impairment in patients and experimental models, focusing on links to vascular dysfunction and structural changes. Lastly, we propose a role for the innate immunity--mediated inflammation in neurovascular changes in diabetes. PMID:27634842

Type 2 responses at the interface between immunity and fat metabolism.

PubMed

Odegaard, Justin I; Chawla, Ajay

2015-10-01

Adipose tissue resident leukocytes are often cast solely as the effectors of obesity and its attendant pathologies; however, recent observations have demonstrated that these cells support and effect 'healthy' physiologic function as well as pathologic dysfunction. Importantly, these two disparate outcomes are underpinned by similarly disparate immune programs; type 2 responses instruct and promote metabolic normalcy, while type 1 responses drive tissue dysfunction. In this Review, we summarize the literature regarding type 2 immunity's role in adipose tissue physiology and allude to its potential therapeutic implications. Copyright © 2015 Elsevier Ltd. All rights reserved.

PCSK9 at the crossroad of cholesterol metabolism and immune function during infections.

PubMed

Paciullo, Francesco; Fallarino, Francesca; Bianconi, Vanessa; Mannarino, Massimo R; Sahebkar, Amirhossein; Pirro, Matteo

2017-09-01

Sepsis, a complex and dynamic syndrome resulting from microbial invasion and immune system dysregulation, is associated with an increased mortality, reaching up to 35% worldwide. Cholesterol metabolism is often disturbed during sepsis, with low plasma cholesterol levels being associated with poor prognosis. Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes degradation of the low-density lipoprotein receptor (LDLR), thus regulating intracellular and plasma cholesterol levels. PCSK9 is often upregulated during sepsis and might have a detrimental effect on immune host response and survival. Accordingly, PCSK9 reduces lipopolysaccharide uptake and clearance by human hepatocytes. Moreover, PCSK9 upregulation exacerbates organ dysfunction and tissue inflammation during sepsis, whereas a protective effect of PCSK9 deficiency has been documented in septic patients. Although a possible detrimental impact of PCSK9 on survival has been described, some beneficial effects of PCSK9 on immune response may be hypothesized. First, PCSK9 is associated with increased plasma cholesterol levels, which might be protective during sepsis. Second, PCSK9, by stimulating LDLR degradation and inhibiting reverse cholesterol transport (RCT), might promote preferential cholesterol accumulation in macrophages and other immune cells; these events might improve lipid raft composition and augment toll-like receptor function thus supporting inflammatory response. Hence, a more clear definition of the role of PCSK9 in septic states might provide additional insight in the understanding of the sepsis-associated immune dysregulation and enhance therapeutic outcomes. © 2017 Wiley Periodicals, Inc.

Study protocol to examine the effects of spaceflight and a spaceflight analog on neurocognitive performance: extent, longevity, and neural bases

PubMed Central

2013-01-01

Background Long duration spaceflight (i.e., 22 days or longer) has been associated with changes in sensorimotor systems, resulting in difficulties that astronauts experience with posture control, locomotion, and manual control. The microgravity environment is an important causal factor for spaceflight induced sensorimotor changes. Whether spaceflight also affects other central nervous system functions such as cognition is yet largely unknown, but of importance in consideration of the health and performance of crewmembers both in- and post-flight. We are therefore conducting a controlled prospective longitudinal study to investigate the effects of spaceflight on the extent, longevity and neural bases of sensorimotor and cognitive performance changes. Here we present the protocol of our study. Methods/design This study includes three groups (astronauts, bed rest subjects, ground-based control subjects) for which each the design is single group with repeated measures. The effects of spaceflight on the brain will be investigated in astronauts who will be assessed at two time points pre-, at three time points during-, and at four time points following a spaceflight mission of six months. To parse out the effect of microgravity from the overall effects of spaceflight, we investigate the effects of seventy days head-down tilted bed rest. Bed rest subjects will be assessed at two time points before-, two time points during-, and three time points post-bed rest. A third group of ground based controls will be measured at four time points to assess reliability of our measures over time. For all participants and at all time points, except in flight, measures of neurocognitive performance, fine motor control, gait, balance, structural MRI (T1, DTI), task fMRI, and functional connectivity MRI will be obtained. In flight, astronauts will complete some of the tasks that they complete pre- and post flight, including tasks measuring spatial working memory, sensorimotor adaptation, and fine motor performance. Potential changes over time and associations between cognition, motor-behavior, and brain structure and function will be analyzed. Discussion This study explores how spaceflight induced brain changes impact functional performance. This understanding could aid in the design of targeted countermeasures to mitigate the negative effects of long-duration spaceflight. PMID:24350728

Growth and Remodeling in Blood Vessels Studied In Vivo With Fractal Analysis

NASA Technical Reports Server (NTRS)

Parsons-Wingerter, Patricia A.

2003-01-01

Every cell in the human body must reside in close proximity to a blood vessel (within approximately 200 mm) because blood vessels provide the oxygen, metabolite, and fluid exchanges required for cellular existence. The growth and remodeling of blood vessels are required to support the normal physiology of embryonic development, reproductive biology, wound healing and adaptive remodeling to exercise, as well as abnormal tissue change in diseases such as cancer, diabetes, and coronary heart disease. Cardiovascular and hemodynamic (blood flow dynamics) alterations experienced by astronauts during long-term spaceflight, including orthostatic intolerance, fluid shifts in the body, and reduced numbers of red (erythrocyte) and white (immune) blood cells, are identified as risk factors of very high priority in the NASA task force report on risk reduction for human spaceflight, the "Critical Path Roadmap."

Evidence Report: Risk Factor of Inadequate Nutrition

NASA Technical Reports Server (NTRS)

Smith, Scott M.; Zwart, Sara R.; Heer, Martina

2015-01-01

The importance of nutrition in exploration has been documented repeatedly throughout history, where, for example, in the period between Columbus' voyage in 1492 and the invention of the steam engine, scurvy resulted in more sailor deaths than all other causes of death combined. Because nutrients are required for the structure and function of every cell and every system in the body, defining the nutrient requirements for spaceflight and ensuring provision and intake of those nutrients are primary issues for crew health and mission success. Unique aspects of nutrition during space travel include the overarching physiological adaptation to weightlessness, psychological adaptation to extreme and remote environments, and the ability of nutrition and nutrients to serve as countermeasures to ameliorate the negative effects of spaceflight on the human body. Key areas of clinical concern for long-duration spaceflight include loss of body mass (general inadequate food intake), bone and muscle loss, cardiovascular and immune system decrements, increased radiation exposure and oxidative stress, vision and ophthalmic changes, behavior and performance, nutrient supply during extravehicular activity, and general depletion of body nutrient stores because of inadequate food supply, inadequate food intake, increased metabolism, and/or irreversible loss of nutrients. These topics are reviewed herein, based on the current gap structure.

Space flight and bone formation.

PubMed

Doty, St B

2004-12-01

Major physiological changes which occur during spaceflight include bone loss, muscle atrophy, cardiovascular and immune response alterations. When trying to determine the reason why bone loss occurs during spaceflight, one must remember that all these other changes in physiology and metabolism may also have impact on the skeletal system. For bone, however, the role of normal weight bearing is a major concern and we have found no adequate substitute for weight bearing which can prevent bone loss. During the study of this problem, we have learned a great deal about bone physiology and increased our knowledge about how normal bone is formed and maintained. Presently, we do not have adequate ground based models which can mimic the tissue loss that occurs in spaceflight but this condition closely resembles the bone loss seen with osteoporosis. Although a normal bone structure will respond to application of mechanical force and weight bearing by forming new bone, a weakened osteoporotic bone may have a tendency to fracture. The study of the skeletal system during weightless conditions will eventually produce preventative measures and form a basis for protecting the crew during long term space flight. The added benefit from these studies will be methods to treat bone loss conditions which occur here on earth.

Space flight and bone formation

NASA Technical Reports Server (NTRS)

Doty, St B.

2004-01-01

Major physiological changes which occur during spaceflight include bone loss, muscle atrophy, cardiovascular and immune response alterations. When trying to determine the reason why bone loss occurs during spaceflight, one must remember that all these other changes in physiology and metabolism may also have impact on the skeletal system. For bone, however, the role of normal weight bearing is a major concern and we have found no adequate substitute for weight bearing which can prevent bone loss. During the study of this problem, we have learned a great deal about bone physiology and increased our knowledge about how normal bone is formed and maintained. Presently, we do not have adequate ground based models which can mimic the tissue loss that occurs in spaceflight but this condition closely resembles the bone loss seen with osteoporosis. Although a normal bone structure will respond to application of mechanical force and weight bearing by forming new bone, a weakened osteoporotic bone may have a tendency to fracture. The study of the skeletal system during weightless conditions will eventually produce preventative measures and form a basis for protecting the crew during long term space flight. The added benefit from these studies will be methods to treat bone loss conditions which occur here on earth.

Effects of spaceflight on the immunoglobulin repertoire of unimmunized C57BL/6 mice.

PubMed

Ward, Claire; Rettig, Trisha A; Hlavacek, Savannah; Bye, Bailey A; Pecaut, Michael J; Chapes, Stephen K

2018-02-01

Spaceflight has been shown to suppress the adaptive immune response, altering the distribution and function of lymphocyte populations. B lymphocytes express highly specific and highly diversified receptors, known as immunoglobulins (Ig), that directly bind and neutralize pathogens. Ig diversity is achieved through the enzymatic splicing of gene segments within the genomic DNA of each B cell in a host. The collection of Ig specificities within a host, or Ig repertoire, has been increasingly characterized in both basic research and clinical settings using high-throughput sequencing technology (HTS). We utilized HTS to test the hypothesis that spaceflight affects the B-cell repertoire. To test this hypothesis, we characterized the impact of spaceflight on the unimmunized Ig repertoire of C57BL/6 mice that were flown aboard the International Space Station (ISS) during the Rodent Research One validation flight in comparison to ground controls. Individual gene segment usage was similar between ground control and flight animals, however, gene segment combinations and the junctions in which gene segments combine was varied among animals within and between treatment groups. We also found that spontaneous somatic mutations in the IgH and Igκ gene loci were not increased. These data suggest that space flight did not affect the B cell repertoire of mice flown and housed on the ISS over a short period of time. Copyright © 2017 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

Humanizing outer space: architecture, habitability, and behavioral health

NASA Astrophysics Data System (ADS)

Harrison, Albert A.

2010-03-01

Space architecture is the theory and practice of designing and building environments for humans in outer space. In our present century professional astronauts and cosmonauts will remain a focus for space architects, but new designs must better accommodate passengers (tourists and industrial workers) and settlers who set forth to establish off-world societies. Psychologists and architects can work together to assure good spaceflight behavioral health, defined by a lack of neuropsychiatric dysfunction, and the presence of high levels of personal adjustment, cordial interpersonal relations, and positive interactions with the physical and social environments. By designing and constructing facilities that are occupant centered and activity oriented, architects increase habitability thereby decreasing environmental challenges to behavioral health. Simulators and spaceflight-analogous environments make it possible to test design solutions prior to their deployment in space. This paper concludes with suggestions for increasing collaboration between architects and psychologists. These include increased sharing of hypotheses and data, articulating complementary research styles, and mutual advocacy for early, potent, and sustained involvement in mission planning and execution.

Regulation of metabolic health and adipose tissue function by group 2 innate lymphoid cells.

PubMed

Cautivo, Kelly M; Molofsky, Ari B

2016-06-01

Adipose tissue (AT) is home to an abundance of immune cells. With chronic obesity, inflammatory immune cells accumulate and promote insulin resistance and the progression to type 2 diabetes mellitus. In contrast, recent studies have highlighted the regulation and function of immune cells in lean, healthy AT, including those associated with type 2 or "allergic" immunity. Although traditionally activated by infection with multicellular helminthes, AT type 2 immunity is active independently of infection, and promotes tissue homeostasis, AT "browning," and systemic insulin sensitivity, protecting against obesity-induced metabolic dysfunction and type 2 diabetes mellitus. In particular, group 2 innate lymphoid cells (ILC2s) are integral regulators of AT type 2 immunity, producing the cytokines interleukin-5 and IL-13, promoting eosinophils and alternatively activated macrophages, and cooperating with and promoting AT regulatory T (Treg) cells. In this review, we focus on the recent developments in our understanding of group 2 innate lymphoid cell cells and type 2 immunity in AT metabolism and homeostasis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Regulation of metabolic health and adipose tissue function by group 2 innate lymphoid cells

PubMed Central

Cautivo, Kelly M.; Molofsky, Ari B.

2016-01-01

Adipose tissue (AT) is home to an abundance of immune cells. With chronic obesity, inflammatory immune cells accumulate and promote insulin resistance and the progression to type 2 diabetes mellitus (T2DM). In contrast, recent studies have highlighted the regulation and function of immune cells in lean, healthy adipose tissue, including those associated with type 2 or “allergic” immunity. Although traditionally activated by infection with multicellular helminthes, AT type 2 immunity is active independently of infection, and promotes tissue homeostasis, adipose tissue “browning”, and systemic insulin sensitivity, protecting against obesity-induced metabolic dysfunction and T2DM. In particular, group 2 innate lymphoid cells (ILC2s) are integral regulators of AT type 2 immunity, producing the cytokines IL-5 and IL-13, promoting eosinophils and alternatively activated macrophages, and cooperating with and promoting AT regulatory T (Treg) cells. In this review, we focus on the recent developments in our understanding of ILC2 cells and type 2 immunity in adipose tissue metabolism and homeostasis. PMID:27120716

Aberrant immune response with consequent vascular and connective tissue remodeling - causal to scleroderma and associated syndromes such as Raynaud phenomenon and other fibrosing syndromes?

PubMed

Durmus, Nedim; Park, Sung-Hyun; Reibman, Joan; Grunig, Gabriele

2016-11-01

Scleroderma and other autoimmune-induced connective tissue diseases are characterized by dysfunctions in the immune system, connective tissue and the vasculature. We are focusing on systemic sclerosis (SSc)-associated pulmonary hypertension, which remains a leading cause of death with only a 50-60% of 2-year survival rate. Much research and translational efforts have been directed at understanding the immune response that causes SSc and the networked interactions with the connective tissue and the vasculature. One of the unexpected findings was that in some cases the pathogenic immune response in SSc resembles the immune response to helminth parasites. During coevolution, means of communication were developed which protect the host from over-colonization with parasites and which protect the parasite from excessive host responses. One explanation for the geographically clustered occurrence of SSc is that environmental exposures combined with genetic predisposition turn on triggers of molecular and cellular modules that were once initiated by parasites. Future research is needed to further understand the parasite-derived signals that dampen the host response. Therapeutic helminth infection or treatment with parasite-derived response modifiers could be promising new management tools for autoimmune connective tissue diseases.

On Representative Spaceflight Instrument and Associated Instrument Sensor Web Framework

NASA Technical Reports Server (NTRS)

Kizhner, Semion; Patel, Umeshkumar; Vootukuru, Meg

2007-01-01

Sensor Web-based adaptation and sharing of space flight mission resources, including those of the Space-Ground and Control-User communication segment, could greatly benefit from utilization of heritage Internet Protocols and devices applied for Spaceflight (SpaceIP). This had been successfully demonstrated by a few recent spaceflight experiments. However, while terrestrial applications of Internet protocols are well developed and understood (mostly due to billions of dollars in investments by the military and industry), the spaceflight application of Internet protocols is still in its infancy. Progress in the developments of SpaceIP-enabled instrument components will largely determine the SpaceIP utilization of those investments and acceptance in years to come. Likewise SpaceIP, the development of commercial real-time and instrument colocated computational resources, data compression and storage, can be enabled on-board a spacecraft and, in turn, support a powerful application to Sensor Web-based design of a spaceflight instrument. Sensor Web-enabled reconfiguration and adaptation of structures for hardware resources and information systems will commence application of Field Programmable Arrays (FPGA) and other aerospace programmable logic devices for what this technology was intended. These are a few obvious potential benefits of Sensor Web technologies for spaceflight applications. However, they are still waiting to be explored. This is because there is a need for a new approach to spaceflight instrumentation in order to make these mature sensor web technologies applicable for spaceflight. In this paper we present an approach in developing related and enabling spaceflight instrument-level technologies based on the new concept of a representative spaceflight Instrument Sensor Web (ISW).

Dynamics of mononuclear phagocyte system Fc receptor function in systemic lupus erythematosus. Relation to disease activity and circulating immune complexes.

PubMed Central

Kimberly, R P; Parris, T M; Inman, R D; McDougal, J S

1983-01-01

Seventeen pairs of longitudinal studies of mononuclear phagocyte system (MPS) Fc receptor function in 15 patients with systemic lupus were performed to explore the dynamic range of Fc receptor dysfunction in lupus and to establish the relationships between MPS function, clinical disease activity and circulating immune complexes (CIC). Fc receptor function was measured by the clearance of IgG sensitized autologous erythrocytes. At the time of first study the degree of MPS dysfunction was correlated with both clinical activity (P less than 0.05) and CIC (P less than 0.05). At follow-up patients with a change in clinical status show significantly larger changes in clearance function compared to clinically stable patients (206 min vs 7 min; P less than 0.001). MPS function changed concordantly with a change in clinical status in all cases (P = 0.002). Longitudinal assessments did not demonstrate concordance of changes in MPS function and CIC, measured by three different assays. The MPS Fc receptor defect in systemic lupus is dynamic and closely associated with disease activity. The lack of concordance of the defect with changes in CIC suggests that either CIC does not adequately reflect receptor site saturation or that other factors may also contribute to the magnitude of MPS dysfunction. PMID:6839542

Immune system gene dysregulation in autism and schizophrenia.

PubMed

Michel, Maximilian; Schmidt, Martin J; Mirnics, Karoly

2012-10-01

Gene*environment interactions play critical roles in the emergence of autism and schizophrenia pathophysiology. In both disorders, recent genetic association studies have provided evidence for disease-linked variation in immune system genes and postmortem gene expression studies have shown extensive chronic immune abnormalities in brains of diseased subjects. Furthermore, peripheral biomarker studies revealed that both innate and adaptive immune systems are dysregulated. In both disorders symptoms of the disease correlate with the immune system dysfunction; yet, in autism this process appears to be chronic and sustained, while in schizophrenia it is exacerbated during acute episodes. Furthermore, since immune abnormalities endure into adulthood and anti-inflammatory agents appear to be beneficial, it is likely that these immune changes actively contribute to disease symptoms. Modeling these changes in animals provided further evidence that prenatal maternal immune activation alters neurodevelopment and leads to behavioral changes that are relevant for autism and schizophrenia. The converging evidence strongly argues that neurodevelopmental immune insults and genetic background critically interact and result in increased risk for either autism or schizophrenia. Further research in these areas may improve prenatal health screening in genetically at-risk families and may also lead to new preventive and/or therapeutic strategies. Copyright © 2012 Wiley Periodicals, Inc.

Effect of long-duration spaceflight on postural control during self-generated perturbations

NASA Technical Reports Server (NTRS)

Layne, C. S.; Mulavara, A. P.; McDonald, P. V.; Pruett, C. J.; Kozlovskaya, I. B.; Bloomberg, J. J.

2001-01-01

This report is the first systematic evaluation of the effects of prolonged weightlessness on the bipedal postural control processes during self-generated perturbations produced by voluntary upper limb movements. Spaceflight impacts humans in a variety of ways, one of which is compromised postflight postural control. We examined the neuromuscular activation characteristics and center of pressure (COP) motion associated with arm movement of eight subjects who experienced long-duration spaceflight (3--6 mo) aboard the Mir space station. Surface electromyography, arm acceleration, and COP motion were collected while astronauts performed rapid unilateral shoulder flexions before and after spaceflight. Subjects generally displayed compromised postural control after flight, as evidenced by modified COP peak-to-peak anterior-posterior and mediolateral excursion, and pathlength relative to preflight values. These changes were associated with disrupted neuromuscular activation characteristics, particularly after the completion of arm acceleration (i.e., when subjects were attempting to maintain upright posture in response to self-generated perturbations). These findings suggest that, although the subjects were able to assemble coordination modes that enabled them to generate rapid arm movements, the subtle control necessary to maintain bipedal equilibrium evident in their preflight performance is compromised after long-duration spaceflight.

Effect of Long-Duration Spaceflight on Postural Control During Self-Generated Perturbations

NASA Technical Reports Server (NTRS)

Layne, Charles S.; Mulavera, Ajitkumar P.; McDonald, P. Vernon; Pruett, Casey J.; Kozlovskaya, Innessa B.; Bloomberg, Jacob J.

2001-01-01

This report is the first systematic evaluation of the effects of prolonged weightlessness on the bipedal postural control processes during self-generated perturbations produced by voluntary upper limb movements. Spaceflight impacts humans in a variety of ways, one of which is compromised postflight postural control. We examined the neuromuscular activation characteristics and center of pressure motion (COP) associated with arm movement of eight subjects who experienced long duration spaceflight (3-6 months) aboard the Mir space station. Surface electromyography (EMG), arm acceleration, and COP motion were collected while astronauts performed rapid unilateral shoulder flexions prior to and after spaceflight. Subjects displayed compromised postural control after flight as evidenced by modified peak-to-peak COP anterior-posterior and medio-lateral motion and COP pathlength relative to preflight values. These changes were associated with disrupted neuromuscular activation characteristics, particularly after the completion of arm acceleration (i.e. when subjects were attempting to maintain their upright posture). These findings suggest that although the subjects were able to assemble coordination modes that enabled them to generate rapid arm movements, the subtle control necessary to maintain bipedal equilibrium evident in their preflight performance is compromised after long duration spaceflight.

Nucleic acid sensing and innate immunity: signaling pathways controlling viral pathogenesis and autoimmunity.

PubMed

Ahlers, Laura R H; Goodman, Alan G

2016-09-01

Innate immunity refers to the body's initial response to curb infection upon exposure to invading organisms. While the detection of pathogen-associated molecules is an ancient form of host defense, if dysfunctional, autoimmune disease may result. The innate immune response during pathogenic infection is initiated through the activation of receptors recognizing conserved molecular patterns, such as nucleic acids from a virus' genome or replicative cycle. Additionally, the host's own nucleic acids are capable of activating an immune response. Therefore, it follows that the nucleic acid-sensing pathways must be tightly controlled to avoid an autoimmune response from recognition of self, yet still be unimpeded to respond to viral infections. In this review, we will describe the nucleic acid sensing pathways and how they respond to virus infection. Moreover, we will discuss autoimmune diseases that develop when these pathways fail to signal properly and identify knowledge gaps that are prime for interrogation.

HLA Immune Function Genes in Autism

PubMed Central

Torres, Anthony R.; Westover, Jonna B.; Rosenspire, Allen J.

2012-01-01

The human leukocyte antigen (HLA) genes on chromosome 6 are instrumental in many innate and adaptive immune responses. The HLA genes/haplotypes can also be involved in immune dysfunction and autoimmune diseases. It is now becoming apparent that many of the non-antigen-presenting HLA genes make significant contributions to autoimmune diseases. Interestingly, it has been reported that autism subjects often have associations with HLA genes/haplotypes, suggesting an underlying dysregulation of the immune system mediated by HLA genes. Genetic studies have only succeeded in identifying autism-causing genes in a small number of subjects suggesting that the genome has not been adequately interrogated. Close examination of the HLA region in autism has been relatively ignored, largely due to extraordinary genetic complexity. It is our proposition that genetic polymorphisms in the HLA region, especially in the non-antigen-presenting regions, may be important in the etiology of autism in certain subjects. PMID:22928105

Immune function and brain abnormalities in patients with systemic lupus erythematosus without overt neuropsychiatric manifestations.

PubMed

Kozora, E; Filley, C M; Zhang, L; Brown, M S; Miller, D E; Arciniegas, D B; Pelzman, J L; West, S G

2012-04-01

This study examined the relationship between immune, cognitive and neuroimaging assessments in subjects with systemic lupus erythematosus (SLE) without histories of overt neuropsychiatric (NP) disorders. In total, 84 subjects with nonNPSLE and 37 healthy controls completed neuropsychological testing from the American College of Rheumatology SLE battery. Serum autoantibody and cytokine measures, volumetric magnetic resonance imaging, and magnetic resonance spectroscopy data were collected on a subset of subjects. NonNPSLE subjects had lower scores on measures of visual/complex attention, visuomotor speed and verbal memory compared with controls. No clinically significant differences between nonNPSLE patients and controls were found on serum measures of lupus anticoagulant, anticardiolipin antibodies, beta 2-glycoproteins, or pro-inflammatory cytokines (interleukin (IL)-1, IL-6, interferon alpha (IFN-alpha), and interferon gamma (IFN-gamma)). Higher scores on a global cognitive impairment index and a memory impairment index were correlated with lower IFN-alpha. Few associations between immune functions and neuroimaging parameters were found. Results indicated that nonNPSLE patients demonstrated cognitive impairment but not immune differences compared with controls. In these subjects, who were relatively young and with mild disease, no relationship between cognitive dysfunction, immune parameters, or previously documented neuroimaging abnormalities were noted. Immune measures acquired from cerebrospinal fluid instead of serum may yield stronger associations.

Allicin Alleviates Reticuloendotheliosis Virus-Induced Immunosuppression via ERK/Mitogen-Activated Protein Kinase Pathway in Specific Pathogen-Free Chickens

PubMed Central

Wang, Liyuan; Jiao, Hongchao; Zhao, Jingpeng; Wang, Xiaojuan; Sun, Shuhong; Lin, Hai

2017-01-01

Reticuloendotheliosis virus (REV), a gammaretrovirus in the Retroviridae family, causes an immunosuppressive, oncogenic, and runting–stunting syndrome in multiple avian hosts. Allicin, the main effective component of garlic, has a broad spectrum of pharmacological properties. The hypothesis that allicin could relieve REV-induced immune dysfunction was investigated in vivo and in vitro in the present study. The results showed that dietary allicin supplementation ameliorated REV-induced dysplasia and immune dysfunction in REV-infected chickens. Compared with the control groups, REV infection promoted the expression of inflammatory cytokines including interleukin (IL)-1β, IL-6, IL-10, interferon (IFN)-γ, and tumor necrosis factor-α (TNF-α), whereas, allicin reversed these changes induced by REV infection. The decreased levels of IFN-α, IFN-β, and IL-2 were observed in REV-infected chickens, which were significantly improved by allicin. Allicin suppressed the REV-induced high expression of toll-like receptors (TLRs) as well as melanoma differentiation-associated gene 5 (MDA5) and the activation of mitogen-activated protein kinase (MAPK) and the nuclear factor kappa B p65. REV stimulated the phosphorylation of JNK, ERK, and p38, the downstream key signaling molecules of MAPK pathway, while allicin retarded the augmented phosphorylation level induced by REV infection. The decreased phosphorylation level of ERK was associated with REV replication, suggesting that ERK signaling is involved in REV replication, and allicin can alleviate the REV-induced immune dysfunction by inhibiting the activation of ERK. In addition, REV infection induced oxidative damage in thymus and spleen, whereas allicin treatment significantly decreased the oxidative stress induced by REV infection, suggesting that the antioxidant effect of allicin should be at least partially responsible for the harmful effect of REV infection. In conclusion, the findings suggest that allicin alleviates the inflammation and oxidative damage caused by REV infection and exerts the potential anti-REV effect by blocking the ERK/MAPK pathway. PMID:29312337

Short-term Exposure to Microgravity and the Associated Risk of Sudden Cardiac Arrest: Implications for Commercial Spaceflight

NASA Astrophysics Data System (ADS)

Laing, Kevin J. C.; Russamono, Thais

2013-02-01

The likelihood of trained astronauts developing a life threatening cardiac event during spaceflight is relatively rare, whilst the incidence in untrained individuals is unknown. Space tourists who live a sedentary lifestyle have reduced cardiovascular function, but the associated danger of sudden cardiac arrest (SCA) during a suborbital spaceflight (SOSF) is unclear. Risk during SOSF was examined by reviewing several microgravity studies and methods of determining poor cardiovascular condition. Accurately assessing cardiovascular function and improving baroreceptor sensitivity through exercise is suggested to reduce the incidence of SCA during future SOSFs. Future studies will benefit from past participants sharing medical history; allowing creation of risk profiles and suitable guidelines.

Non-celiac gluten sensitivity triggers gut dysbiosis, neuroinflammation, gut-brain axis dysfunction, and vulnerability for dementia.

PubMed

Daulatzai, Mak Adam

2015-01-01

The non-celiac gluten sensitivity (NCGS) is a chronic functional gastrointestinal disorder which is very common world wide. The human gut harbors microbiota which has a wide variety of microbial organisms; they are mainly symbiotic and important for well being. However, "dysbiosis" - i.e. an alteration in normal commensal gut microbiome with an increase in pathogenic microbes, impacts homeostasis/health. Dysbiosis in NCGS causes gut inflammation, diarrhea, constipation, visceral hypersensitivity, abdominal pain, dysfunctional metabolic state, and peripheral immune and neuro-immune communication. Thus, immune-mediated gut and extra-gut dysfunctions, due to gluten sensitivity with comorbid diarrhea, may last for decades. A significant proportion of NCGS patients may chronically consume alcohol, non-steroidal anti-inflammatory drugs, and fatty diet, as well as suffer from various comorbid disorders. The above pathophysiological substrate and dysbiosis are underpinned by dysfunctional bidirectional "Gut-Brain Axis" pathway. Pathogenic gut microbiota is known to upregulate gut- and systemic inflammation (due to lipopolysaccharide from pathogenic bacteria and synthesis of pro-inflammatory cytokines); they enhance energy harvest, cause obesity, insulin resistance, and dysfunctional vago-vagal gut-brain axis. Conceivably, the above cascade of pathology may promote various pathophysiological mechanisms, neuroinflammation, and cognitive dysfunction. Hence, dysbiosis, gut inflammation, and chronic dyshomeostasis are of great clinical relevance. It is argued here that we need to be aware of NCGS and its chronic pathophysiological impact. Therapeutic measures including probiotics, vagus nerve stimulation, antioxidants, alpha 7 nicotinic receptor agonists, and corticotropin-releasing factor receptor 1 antagonist may ameliorate neuroinflammation and oxidative stress in NCGS; they may therefore, prevent cognitive dysfunction and vulnerability to Alzheimer's disease.

Beyond infection - Maternal immune activation by environmental factors, microglial development, and relevance for autism spectrum disorders.

PubMed

Bilbo, Staci D; Block, Carina L; Bolton, Jessica L; Hanamsagar, Richa; Tran, Phuong K

2018-01-01

Immune molecules such as cytokines and chemokines and the cells that produce them within the brain, notably microglia, are critical for normal brain development. This recognition has in recent years led to the working hypothesis that inflammatory events during pregnancy, e.g. in response to infection, may disrupt the normal expression of immune molecules during critical stages of neural development and thereby contribute to the risk for neurodevelopmental disorders such as autism spectrum disorder (ASD). This hypothesis has in large part been shepherded by the work of Dr. Paul Patterson and colleagues, which has elegantly demonstrated that a single viral infection or injection of a viral mimetic to pregnant mice significantly and persistently impacts offspring immune and nervous system function, changes that underlie ASD-like behavioral dysfunction including social and communication deficits. Subsequent studies by many labs - in humans and in non-human animal models - have supported the hypothesis that ongoing disrupted immune molecule expression and/or neuroinflammation contributes to at least a significant subset of ASD. The heterogeneous clinical and biological phenotypes observed in ASD strongly suggest that in genetically susceptible individuals, environmental risk factors combine or synergize to create a tipping or threshold point for dysfunction. Importantly, animal studies showing a link between maternal immune activation (MIA) and ASD-like outcomes in offspring involve different species and diverse environmental factors associated with ASD in humans, beyond infection, including toxin exposures, maternal stress, and maternal obesity, all of which impact inflammatory or immune pathways. The goal of this review is to highlight the broader implications of Dr. Patterson's work for the field of autism, with a focus on the impact that MIA by diverse environmental factors has on fetal brain development, immune system development, and the pathophysiology of ASD. Copyright © 2017 Elsevier Inc. All rights reserved.

Drosophila type IV collagen mutation associates with immune system activation and intestinal dysfunction.

PubMed

Kiss, Márton; Kiss, András A; Radics, Monika; Popovics, Nikoletta; Hermesz, Edit; Csiszár, Katalin; Mink, Mátyás

2016-01-01

The basal lamina (BM) contains numerous components with a predominance of type IV collagens. Clinical manifestations associated with mutations of the human COL4A1 gene include perinatal cerebral hemorrhage and porencephaly, hereditary angiopathy, nephropathy, aneurysms and muscle cramps (HANAC), ocular dysgenesis, myopathy, Walker–Warburg syndrome and systemic tissue degeneration. In Drosophila, the phenotype associated with dominant temperature sensitive mutations of col4a1 include severe myopathy resulting from massive degradation of striated muscle fibers, and in the gut, degeneration of circular visceral muscle cells and epithelial cells following detachment from the BM. In order to determine the consequences of altered BMfunctions due to aberrant COL4A1 protein, we have carried out a series of tests using Drosophila DTS-L3 mutants from our allelic series of col4a1 mutations with confirmed degeneration of various cell types and lowest survival rate among the col4a1 mutant lines at restrictive temperature. Results demonstrated epithelial cell degeneration in the gut, shortened gut, enlarged midgut with multiple diverticulae, intestinal dysfunction and shortened life span. Midgut immunohistochemistry analyses confirmed altered expression and distribution of BM components integrin PSI and PSII alpha subunits, laminin gamma 1, and COL4A1 both in larvae and adults. Global gene expression analysis revealed activation of the effector AMP genes of the primary innate immune system including Metchnikowin, Diptericin, Diptericin B, and edin that preceded morphological changes. Attacin::GFP midgut expression pattern further supported these changes. An increase in ROS production and changes in gut bacterial flora were also noted and may have further enhanced an immune response. The phenotypic features of Drosophila col4a1 mutants confirmed an essential role for type IV collagen in maintaining epithelial integrity, gut morphology and intestinal function and suggest that aberrant structure and function of the COL4A1 protein may also be a significant factor in modulating immunity.

Hypocretin-1 CSF levels in anti-Ma2 associated encephalitis.

PubMed

Overeem, S; Dalmau, J; Bataller, L; Nishino, S; Mignot, E; Verschuuren, J; Lammers, G J

2004-01-13

Idiopathic narcolepsy is associated with deficient hypocretin transmission. Narcoleptic symptoms have recently been described in paraneoplastic encephalitis with anti-Ma2 antibodies. The authors measured CSF hypocretin-1 levels in six patients with anti-Ma2 encephalitis, and screened for anti-Ma antibodies in patients with idiopathic narcolepsy. Anti-Ma autoantibodies were not detected in patients with idiopathic narcolepsy. Four patients with anti-Ma2 encephalitis had excessive daytime sleepiness; hypocretin-1 was not detectable in their cerebrospinal fluid, suggesting an immune-mediated hypocretin dysfunction.

Does RBC Storage Age Effect Inflammation, Immune Function and Susceptibility to Transfusion Associated Microchimerism in Critically Ill Patients? Adverse Effects of RBC Storage in Critically Ill Patients

DTIC Science & Technology

2013-12-01

PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Philip Spinella, M.D. 5d. PROJECT NUMBER Philip J. Norris , M.D.; Avani Shah, MPH 5e. TASK NUMBER Email...dysfunction syndrome , serious thrombotic events and nosocomial infections, and ICU and hospital length of stay. Prospective clinical studies investigating

Autoimmunity in the Pathogenesis and Treatment of Keratoconjunctivitis Sicca

PubMed Central

Liu, Katy C.; Huynh, Kyle; Grubbs, Joseph; Davis, Richard M.

2014-01-01

Dry eye is a chronic corneal disease that impacts the quality of life of many older adults. keratoconjunctivitis sicca (KCS), a form of aqueous-deficient dry eye, is frequently associated with Sjögren’s syndrome and mechanisms of autoimmunity. For KCS and other forms of dry eye, current treatments are limited, with many medications providing only symptomatic relief rather than targeting the pathophysiology of disease. Here, we review proposed mechanisms in the pathogenesis of autoimmune-based KCS: genetic susceptibility and disruptions in antigen recognition, immune response, and immune regulation. By understanding the mechanisms of immune dysfunction through basic science and translational research, potential drug targets can be identified. Finally, we discuss current dry eye therapies as well as promising new treatment options and drug therapy targets. PMID:24395332

Increased susceptibility to Pseudomonas aeruginosa infection under hindlimb-unloading conditions

NASA Technical Reports Server (NTRS)

Aviles, Hernan; Belay, Tesfaye; Fountain, Kimberly; Vance, Monique; Sonnenfeld, Gerald

2003-01-01

It has been reported that spaceflight conditions alter the immune system and resistance to infection [Belay T, Aviles H, Vance M, Fountain K, and Sonnenfeld G. J Allergy Clin Immunol 170: 262-268, 2002; Hankins WR and Ziegelschmid JF. In: Biomedical Results of Apollo. Washington, DC: NASA, 1975, p. 43-81. (NASA Spec. Rep. SP-368)]. Ground-based models, including the hindlimb-unloading model, have become important tools for increasing understanding of how spaceflight conditions can influence physiology. The objective of the present study was to determine the effect of hindlimb unloading on the susceptibility of mice to Pseudomonas aeruginosa infection. Hindlimb-unloaded and control mice were subcutaneously infected with 1 LD50 of P. aeruginosa. Survival, bacterial organ load, and antibody and corticosterone levels were compared among the groups. Hindlimb unloading had detrimental effects for infected mice. Animals in the hindlimb-unloaded group, compared with controls, 1). showed significantly increased mortality and reduced time to death, 2). had increased levels of corticosterone, and 3). were much less able to clear bacteria from the organs. These results suggest that hindlimb unloading may induce the production of corticosterone, which may play a critical role in the modulation of the immune system leading to increased susceptibility to P. aeruginosa infection.

Spaceflight Alters Bacterial Gene Expression and Virulence and Reveals Role for Global Regulator Hfq

NASA Technical Reports Server (NTRS)

Wilson, J. W.; Ott, C. M.; zuBentrup, K. Honer; Ramamurthy R.; Quick, L.; Porwollik, S.; Cheng, P.; McClellan, M.; Tsaprailis, G.; Radabaugh, T.;

Responses of motor and sensory neurons of rodents to spaceflight

NASA Technical Reports Server (NTRS)

Ishihara, A.; Ohira, Y.; Roy, R. R.; Nagaoka, S.; Sekiguchi, C.; Edgerton, V. R.

2000-01-01

Spinal motoneurons innervating skeletal muscles comprised predominantly of high oxidative fibers, i.e. slow oxidative and fast oxidative glycolytic, have higher oxidative enzyme activities than motoneurons innervating skeletal muscles comprised primarily of low oxidative fibers, i.e. fast glycolytic. These findings suggest that there is a close relationship between the oxidative phosphorylation capacity of a motoneuron and of the muscle fibers that it innervates. Since some skeletal muscles become faster and less oxidative after 4-14 days of spaceflight, it might be expected that oxidative enzyme activities in some motoneurons also may decrease after spaceflight. In addition, there is significant muscular atrophy after even short spaceflights and, therefore, it may be expected that some motoneurons associated with these muscles also would atrophy. In the present paper, we examine the issue of whether spaceflight induces changes in the oxidative enzyme activity and/or size of spinal motoneurons.

Evidence based selection of probiotic strains to promote astronaut health or alleviate symptoms of illness on long duration spaceflight missions.

PubMed

Douglas, G L; Voorhies, A A

2017-10-13

Spaceflight impacts multiple aspects of human physiology, which will require non-invasive countermeasures as mission length and distance from Earth increases and the capability for external medical intervention decreases. Studies on Earth have shown that probiotics have the potential to improve some of the conditions that have manifested during spaceflight, such as gastrointestinal distress, dermatitis, and respiratory infections. The constraints and risks of spaceflight make it imperative that probiotics are carefully selected based on their strain-specific benefits, doses, delivery mechanisms, and relevance to likely crew conditions prior to evaluation in astronauts. This review focuses on probiotics that have been incorporated into healthy human gastrointestinal microbiomes and associated clinically with improvements in inflammatory state or alleviation of symptoms of crew-relevant illness. These studies provide an evidence base for probiotic selection with the greatest potential to support crew health and well-being in spaceflight.

Center for Cell Research, Pennsylvania State University

NASA Technical Reports Server (NTRS)

Cronin, Mike

1991-01-01

A brief review of Genentech, Inc., is presented. Additionally, the Physiological Systems Experiment (PSE-01) is discussed in terms of its development history. The PSE-01 was developed to investigate the bone wasting, muscle wasting, and immune cell dysfunction that occur in microgravity conditions. Specifically, a number of human disorders are associated with maladaptive changes in bone, muscle, and immune function. The physiological adjustments that the body makes in response to space flight can be monitored and may aid in the discovery of new protein forms and patterns. This research may also provide strategies for protecting the health of flight crews enduring prolonged space flight. Results are discussed.

Commercial spaceflight participant G-force tolerance during centrifuge-simulated suborbital flight.

PubMed

Blue, Rebecca S; Riccitello, Jon M; Tizard, Julia; Hamilton, Richard J; Vanderploeg, James M

2012-10-01

Medical knowledge of the human body in microgravity and hypergravity is based upon studies of healthy individuals well-conditioned for such environments. Little data exist regarding the effects of spaceflight on untrained commercial passengers. We examined the responses of potential spaceflight participants (SFP) to centrifuge G-force exposure. There were 77 individuals (65 men, 12 women), 22-88 yr old, who underwent 6 centrifuge runs over 48 h. Day 1 consisted of two +Gz runs (peak = 3.5+Gz, run 2) and two +Gx runs (peak = 6.0+Gx, run 4). Day 2 consisted of two runs approximating a suborbital spaceflight profile. Data included blood pressure, electrocardiogram, and postrun questionnaires regarding motion sickness, disorientation, greyout, and other symptoms. Of the 77 participants, average age was 50.4 +/- 12.7 yr. Average heart rate (HR) varied by sex and direction of G-exposure (+Gz: F 150 +/- 19, M 123 +/- 27; +Gx: F 135 +/- 30, M 110 +/- 27). Age and peak HR were inversely related (HR < 120 bpm: 60.2 +/- 12.2 yr, HR > 120: 47.1 +/- 10.9 yr). HR during peak G-exposure for the final run was associated with post-run imbalance (no imbalance: HR 126 +/- 26, imbalance: HR 145 +/- 21); no other significant hemodynamic change, sex, or age variation was associated with imbalance. Age and greyout were inversely associated; there was no association between greyout and vital sign change, sex, or G-force magnitude. Baseline/pretrial mean arterial pressure (MAP) was not associated with any symptoms. The results suggest that most individuals with well-controlled medical conditions can withstand acceleration forces involved in launch/landing profiles of commercial spaceflight vehicles. Further investigation will help refine which conditions present significant risk during suborbital flight and beyond.

A mechanism for trauma induced muscle wasting and immune dysfunction

NASA Astrophysics Data System (ADS)

Madihally, S.; Toner, M.; Yarmush, M.; Mitchell, R.

A diverse physiological conditions lead to a hypercatabolic state marked by the loss of proteins, primarily derived from skeletal muscle. The sustained loss of proteins results in loss of muscle mass and strength, poor healing, and long-term hospitalization. These problems are further compounded by the deterioration of immunity to infection which is a leading cause of morbidity and mortality of traumatic patients. In an attempt to understand the signal propagation mechanism(s), we tested the role of Interferon-? (IFN-? ) in an animal burn injury model; IFN-? is best conceptualized as a macrophage activating protein and known to modulate a variety of intracellular processes potentially relevant to muscle wasting and immune dysfunction. Mice congenitally -deficient in IFN-? , and IFN-? -Receptor, and wild type (WT) animals treated with IFN-? neutralizing antibody received either a 20% total body surface area burn or a control sham treatment. At days 1, 2, and 7 following treatment, skeletal muscle, peripheral blood, and spleen were harvested from both groups. Overall body weight, protein turnovers, changes in the lymphocyte subpopulations and alterations in the major histocompatibility complex I expression (MHC I) and proliferation capacity of lymphocytes was measured using mixed lymphocyte reaction (MLR). These results indicate that we can prevent both muscle wasting and immune dysfunction. Based on these observations and our previous other animal model results (using insulin therapy), a novel mechanism of interactions leading to muscle wasting and immune dysfunction will be discussed. Further, implications of these findings on future research and clinical therapies will be discussed in detail.

PPARγ in emphysema: blunts the damage and triggers repair?

PubMed Central

Kelly, Neil J.; Shapiro, Steven D.

2014-01-01

Cigarette smoke is the most common cause of pulmonary emphysema, which results in an irreversible loss of lung structure and function. Th1 and Th17 immune responses have been implicated in emphysema pathogenesis; however, the drivers of emphysema-associated immune dysfunction are not fully understood. In this issue of the JCI, Shan and colleagues found that peroxisome proliferator–activated receptor γ (PPARγ) is downregulated in APCs isolated from the lungs of emphysematous chronic smokers and mice exposed to cigarette smoke. Furthermore, treatment with a PPARγ agonist prevented emphysema development and appeared to reduce emphysema-associated lung volume expansion in mice exposed to cigarette smoke. Further work will need to be done to evaluate the potential of PPARγ agonists to restore lung capacity in emphysematous patients. PMID:24569365

Therapeutic Targets for Management of Periodontitis and Diabetes

PubMed Central

Sima, Corneliu; Van Dyke, Thomas E.

2016-01-01

The increasing incidence of diabetes mellitus (DM) and chronic periodontitis (CP) worldwide imposes a rethinking of individualized therapy for patients with both conditions. Central to bidirectional links between DM and CP is deregulated systemic inflammation and dysfunctional immune responses to altered-self and non-self. Control of blood glucose levels and metabolic imbalances associated with hyperglycemia in DM, and disruption of pathogenic subgingival biofilms in CP are currently the main therapeutic approaches for these conditions. Mounting evidence suggests the need to integrate immune modulatory therapeutics in treatment regimens that address the unresolved inflammation associated with DM and CP. The current review discusses the pathogenesis of DM and CP with emphasis on deregulated inflammation, current therapeutic approaches and the novel pro-resolution lipid mediators derived from n-3 polyunsaturated fatty acids. PMID:26881443

Therapeutic Targets for Management of Periodontitis and Diabetes

PubMed Central

Sima, Corneliu; Van Dyke, Thomas E.

2016-01-01

The increasing incidence of diabetes mellitus (DM) and chronic periodontitis (CP) worldwide imposes a rethinking of individualized therapy for patients with both conditions. Central to bidirectional links between DM and CP is deregulated systemic inflammation and dysfunctional immune responses to altered-self and non-self. Control of blood glucose levels and metabolic imbalances associated with hyperglycemia in DM, and disruption of pathogenic subgingival biofilms in CP are currently the main therapeutic approaches for these conditions. Mounting evidence suggests the need to integrate immune modulatory therapeutics in treatment regimens that address the unresolved inflammation associated with DM and CP. The current review discusses the pathogenesis of DM and CP with emphasis on deregulated inflammation, current therapeutic approaches and the novel pro-resolution lipid mediators derived from Ω-3 polyunsaturated fatty acids.

Hypo-gravity and immune system effects

NASA Technical Reports Server (NTRS)

Carter, Paul D.; Barnes, Frank

1990-01-01

Recent studies on the effects of hypo-gravity on astronauts have shown depressed response of the immune system component cells (e.g. T-lymphocytes activity) and associated bone-mass loss due to demineralization. The widespread use of various electrical stimulation techniques in fracture repair and bone growth make use of the inherent piezoelectric and streaming potentials in Ca(2++) depositation. In-vitro and in-vivo experiments were designed to determine if these potentials, absent or greatly reduced in space, could be artificially enhanced to advantageously effect the bone marrow and, consequently, immune system cells. The bone marrow plays an extremely important role in the development and maturation of all blood cells and, specifically, T- and B-lymphocytes. It is our belief that simulated E-fields will enhance this development when 'ambient' physiological fields are absent during spaceflight or extended bedrest. Our investigation began with a look at the component immune system cells and their growth patterns in vitro. The first chamber will induce E-fields by current densities produced from an agar-bridge electrode arrangement. The cells are immersed in a nutrient agar and isolated from the electrodes by an agar bridge to prevent electrolytic contamination. The second chamber induces current densities by mutual induction from a magnetic field produced by a solenoid coil. Cells are isolated in a small radial area to reduce (1/r) effects and for accurate field calculations. We anticipate inducing currents in the nano- and microampere range as indicated by our calculations of physiological fields.

The Effects of Spaceflight and a Spaceflight Analog on Neurocognitive Perfonnance: Extent, Longevity, and Neural Bases

NASA Technical Reports Server (NTRS)

Seidler, R. D.; Mulavara, A. P.; Koppelmans, V.; Erdeniz, B.; Kofman, I. S.; DeDios, Y. E.; Szecsy, D. L.; Riascos-Castaneda, R. F.; Wood, S. J.; Bloomberg, J. J.

2014-01-01

We are conducting ongoing experiments in which we are performing structural and functional magnetic resonance brain imaging to identify the relationships between changes in neurocognitive function and neural structural alterations following a six month International Space Station mission and following 70 days exposure to a spaceflight analog, head down tilt bedrest. Our central hypothesis is that measures of brain structure, function, and network integrity will change from pre to post intervention (spaceflight, bedrest). Moreover, we predict that these changes will correlate with indices of cognitive, sensory, and motor function in a neuroanatomically selective fashion. Our interdisciplinary approach utilizes cutting edge neuroimaging techniques and a broad ranging battery of sensory, motor, and cognitive assessments that will be conducted pre flight, during flight, and post flight to investigate potential neuroplastic and maladaptive brain changes in crewmembers following long-duration spaceflight. Success in this endeavor would 1) result in identification of the underlying neural mechanisms and operational risks of spaceflight-induced changes in behavior, and 2) identify whether a return to normative behavioral function following re-adaptation to Earth's gravitational environment is associated with a restitution of brain structure and function or instead is supported by substitution with compensatory brain processes. With the bedrest study, we will be able to determine the neural and neurocognitive effects of extended duration unloading, reduced sensory inputs, and increased cephalic fluid distribution. This will enable us to parse out the multiple mechanisms contributing to any spaceflight-induced neural structural and behavioral changes that we observe in the flight study. In this presentation I will discuss preliminary results from six participants who have undergone the bed rest protocol. These individuals show decrements in balance and functional mobility, and alterations in brain structure and function, in association with extended bed rest.

Locomotion in Lymphocytes is Altered by Differential PKC Isoform Expression

NASA Technical Reports Server (NTRS)

Sundaresan, A.; Risin, D.; Pellis, N. R.

1999-01-01

Lymphocyte locomotion is critical for proper elicitation of the immune response. Locomotion of immune cells via the interstitium is essential for optimal immune function during wound healing, inflammation and infection. There are conditions which alter lymphocyte locomotion and one of them is spaceflight. Lymphocyte locomotion is severely inhibited in true spaceflight (true microgravity) and in rotating wall vessel culture (modeled microgravity). When lymphocytes are activated prior to culture in modeled microgravity, locomotion is not inhibited and the levels are comparable to those of static cultured lymphocytes. When a phorbol ester (PMA) is used in modeled microgravity, lymphocyte locomotion is restored by 87%. This occurs regardless if PMA is added after culture in the rotating wall vessel or during culture. Inhibition of DNA synthesis also does not alter restoration of lymphocyte locomotion by PMA. PMA is a direct activator of (protein kinase C) PKC . When a calcium ionophore, ionomycin is used it does not possess any restorative properties towards locomotion either alone or collectively with PMA. Since PMA brings about restoration without help from calcium ionophores (ionomycin), it is infer-red that calcium independent PKC isoforms are involved. Changes were perceived in the protein levels of PKC 6 where levels of the protein were downregulated at 24,72 and 96 hours in untreated rotated cultures (modeled microgravity) compared to untreated static (1g) cultures. At 48 hours there is an increase in the levels of PKC & in the same experimental set up. Studies on transcriptional and translational patterns of calcium independent isoforms of PKC such as 8 and E are presented in this study.

Age-associated changes in monocyte and innate immune activation markers occur more rapidly in HIV infected women.

PubMed

Martin, Genevieve E; Gouillou, Maelenn; Hearps, Anna C; Angelovich, Thomas A; Cheng, Allen C; Lynch, Fiona; Cheng, Wan-Jung; Paukovics, Geza; Palmer, Clovis S; Novak, Richard M; Jaworowski, Anthony; Landay, Alan L; Crowe, Suzanne M

2013-01-01

Aging is associated with immune dysfunction and the related development of conditions with an inflammatory pathogenesis. Some of these immune changes are also observed in HIV infection, but the interaction between immune changes with aging and HIV infection are unknown. Whilst sex differences in innate immunity are recognized, little research into innate immune aging has been performed on women. This cross-sectional study of HIV positive and negative women used whole blood flow cytometric analysis to characterize monocyte and CD8(+) T cell subsets. Plasma markers of innate immune activation were measured using standard ELISA-based assays. HIV positive women exhibited elevated plasma levels of the innate immune activation markers CXCL10 (p<0.001), soluble CD163 (sCD163, p = 0.001), sCD14 (p = 0.022), neopterin (p = 0.029) and an increased proportion of CD16(+) monocytes (p = 0.009) compared to uninfected controls. Levels of the innate immune aging biomarkers sCD163 and the proportion of CD16(+) monocytes were equivalent to those observed in HIV negative women aged 14.5 and 10.6 years older, respectively. CXCL10 increased with age at an accelerated rate in HIV positive women (p = 0.002) suggesting a synergistic effect between HIV and aging on innate immune activation. Multivariable modeling indicated that age-related increases in innate immune biomarkers CXCL10 and sCD163 are independent of senescent changes in CD8(+) T lymphocytes. Quantifying the impact of HIV on immune aging reveals that HIV infection in women confers the equivalent of a 10-14 year increase in the levels of innate immune aging markers. These changes may contribute to the increased risk of inflammatory age-related diseases in HIV positive women.

Immune response against the coiled coil domain of Sjögren's syndrome associated autoantigen Ro52 induces salivary gland dysfunction.

PubMed

Sroka, Magdalena; Bagavant, Harini; Biswas, Indranil; Ballard, Abigail; Deshmukh, Umesh S

2018-01-31

The structural domains of Ro52, termed the RING, B-box, coiled coil (CC) and B30.2/SPRY are targets of anti-Ro52 in multiple autoimmune disorders. In Sjögren's syndrome patients, the presence of anti-Ro52 is associated with higher disease severity, and in mice, they induce salivary gland hypofunction. This study was undertaken to investigate whether immune responses against different domains of Ro52, influences salivary gland disease in mice. Female NZM2758 mice were immunised with Ro52 domains expressed as recombinant fusion proteins with maltose binding protein (MBP) [MBP-RING-B-box, MBP-CC, MBP-CC(ΔC19), MBP-B30.2/SPRY]. Sera from immunised mice were studied for IgG antibodies to Ro52 by immunoprecipitation, and to salivary gland cells by immunofluorescence. Pilocarpine-induced saliva production was measured to evaluate salivary gland function. Submandibular glands were investigated by histopathology for inflammation and by immune-histochemistry for IgG deposition. Mice immunised with different Ro52-domains had comparable reactivity to Ro52 and to salivary gland cells. However, only mice immunised with the CC domain and its C-terminal truncated version CC(ΔC19) showed a significant drop in saliva production. None of the mice developed severe salivary gland inflammation. The salivary gland hypofunction significantly correlated with increased intra-lobar IgG deposits in the submandibular salivary glands. Our data demonstrate that epitope specificity of anti-Ro52 antibodies plays a critical role in the induction of glandular dysfunction. Clearly, screening Sjögren's syndrome patients for relative levels of Ro52 domain specific antibodies will be more informative for associating anti-Ro52 with clinical measures of the disorder.

Gut epithelial barrier dysfunction in human immunodeficiency virus-hepatitis C virus coinfected patients: Influence on innate and acquired immunity.

PubMed

Márquez, Mercedes; Fernández Gutiérrez del Álamo, Clotilde; Girón-González, José Antonio

2016-01-28

Even in cases where viral replication has been controlled by antiretroviral therapy for long periods of time, human immunodeficiency virus (HIV)-infected patients have several non-acquired immunodeficiency syndrome (AIDS) related co-morbidities, including liver disease, cardiovascular disease and neurocognitive decline, which have a clear impact on survival. It has been considered that persistent innate and acquired immune activation contributes to the pathogenesis of these non-AIDS related diseases. Immune activation has been related with several conditions, remarkably with the bacterial translocation related with the intestinal barrier damage by the HIV or by hepatitis C virus (HCV)-related liver cirrhosis. Consequently, increased morbidity and mortality must be expected in HIV-HCV coinfected patients. Disrupted gut barrier lead to an increased passage of microbial products and to an activation of the mucosal immune system and secretion of inflammatory mediators, which in turn might increase barrier dysfunction. In the present review, the intestinal barrier structure, measures of intestinal barrier dysfunction and the modifications of them in HIV monoinfection and in HIV-HCV coinfection will be considered. Both pathogenesis and the consequences for the progression of liver disease secondary to gut microbial fragment leakage and immune activation will be assessed.

Immune Abnormalities in Autism Spectrum Disorder-Could They Hold Promise for Causative Treatment?

PubMed

Gładysz, Dominika; Krzywdzińska, Amanda; Hozyasz, Kamil K

2018-01-06

Autism spectrum disorders (ASD) are characterized by impairments in language and communication development, social behavior, and the occurrence of stereotypic patterns of behavior and interests. Despite substantial speculation about causes of ASD, its exact etiology remains unknown. Recent studies highlight a link between immune dysfunction and behavioral traits. Various immune anomalies, including humoral and cellular immunity along with abnormalities at the molecular level, have been reported. There is evidence of altered immune function both in cerebrospinal fluid and peripheral blood. Several studies hypothesize a role for neuroinflammation in ASD and are supported by brain tissue and cerebrospinal fluid analysis, as well as evidence of microglial activation. It has been shown that immune abnormalities occur in a substantial number of individuals with ASD. Identifying subgroups with immune system dysregulation and linking specific cellular immunophenotypes to different symptoms would be key to defining a group of patients with immune abnormalities as a major etiology underlying behavioral symptoms. These determinations would provide the opportunity to investigate causative treatments for a defined patient group that may specifically benefit from such an approach. This review summarizes recent insights into immune system dysfunction in individuals with ASD and discusses the potential implications for future therapies.

The Transcriptional Response of Diverse Saccharomyces cerevisiae Strains to Simulated Microgravity

NASA Technical Reports Server (NTRS)

Neff, Lilly S.; Fleury, Samantha T.; Galazka, Jonathan M.

2018-01-01

Spaceflight imposes multiple stresses on biological systems resulting in genome-scale adaptations. Understanding these adaptations and their underlying molecular mechanisms is important to clarifying and reducing the risks associated with spaceflight. One such risk is infection by microbes present in spacecraft and their associated systems and inhabitants. This risk is compounded by results suggesting that some microbes may exhibit increased virulence after exposure to spaceflight conditions. The yeast, S. cerevisiae, is a powerful microbial model system, and it's response to spaceflight has been studied for decades. However, to date, these studies have utilized common lab strains. Yet studies on trait variation in S. cerevisiae demonstrate that these lab strains are not representative of wild yeast and instead respond to environmental stimuli in an a typical manner. Thus, it is not clear how transferable these results are to the wild S. cerevisiae strains likely to be encountered during spaceflight. To determine if diverse S. cerevisiae strains exhibit a conserved response to simulated microgravity, we will utilize a collection of 100 S. cerevisiae strains isolated from clinical, environmental and industrial settings. We will place selected S. cerevisiae strains in simulated microgravity using a high-aspect rotating vessel (HARV) and document their transcriptional response by RNA-sequencing and quantify similarities and differences between strains. Our research will have a strong impact on the understanding of how genetic diversity of microorganisms effects their response to spaceflight, and will serve as a platform for further studies.

The Transcriptional Response of Diverse Saccharomyces Cerevisiae Strains to Simulated Microgravity

NASA Technical Reports Server (NTRS)

Neff, Lily S.; Fleury, Samantha T.; Galazka, Jonathan M.

2017-01-01

Spaceflight imposes multiple stresses on biological systems resulting in genome-scale adaptations. Understanding these adaptations and their underlying molecular mechanisms is important to clarifying and reducing the risks associated with spaceflight. One such risk is infection by microbes present in spacecraft and their associated systems and inhabitants. This risk is compounded by results suggesting that some microbes may exhibit increased virulence after exposure to spaceflight conditions. The yeast, S. cerevisiae, is a powerful microbial model system, and its response to spaceflight has been studied for decades. However, to date, these studies have utilized common lab strains. Yet studies on trait variation in S. cerevisiae demonstrate that these lab strains are not representative of wild yeast and instead respond to environmental stimuli in an atypical manner. Thus, it is not clear how transferable these results are to the wild S. cerevisiae strains likely to be encountered during spaceflight. To determine if diverse S. cerevisiae strains exhibit a conserved response to simulated microgravity, we will utilize a collection of 100 S. cerevisiae strains isolated from clinical, environmental and industrial settings. We will place selected S. cerevisiae strains in simulated microgravity using a high-aspect rotating vessel (HARV) and document their transcriptional response by RNA-sequencing and quantify similarities and differences between strains. Our research will have a strong impact on the understanding of how genetic diversity of microorganisms effects their response to spaceflight, and will serve as a platform for further studies.

The Transcriptional Response of Diverse Saccharomyces Cerevisiae Strains to Simulated Microgravity

NASA Technical Reports Server (NTRS)

Neff, Lily S.; Fleury, Samantha T.; Galazka, Jonathan M.

2017-01-01

Spaceflight imposes multiple stresses on biological systems resulting in genome-scale adaptations. Understanding these adaptations and their underlying molecular mechanisms is important to clarifying and reducing the risks associated with spaceflight. One such risk is infection by microbes present in spacecraft and their associated systems and inhabitants. This risk is compounded by results suggesting that some microbes may exhibit increased virulence after exposure to spaceflight conditions. The yeast, S. cerevisiae, is a powerful microbial model system, and it's response to spaceflight has been studied for decades. However, to date, these studies have utilized common lab strains. Yet studies on trait variation in S. cerevisiae demonstrate that these lab strains are not representative of wild yeast and instead respond to environmental stimuli in an atypical manner. Thus, it is not clear how transferable these results are to the wild S. cerevisiae strains likely to be encountered during spaceflight. To determine if diverse S. cerevisiae strains exhibit a conserved response to simulated microgravity, we will utilize a collection of 100 S. cerevisiae strains isolated from clinical, environmental and industrial settings. We will place selected S. cerevisiae strains in simulated microgravity using a high-aspect rotating vessel (HARV) and document their transcriptional response by RNA-sequencing and quantify similarities and differences between strains. Our research will have a strong impact on the understanding of how genetic diversity of microorganisms effects their response to spaceflight, and will serve as a platform for further studies.

The Transcriptional Response of Diverse Saccharomyces cerevisiae Strains to Simulated Microgravity

NASA Technical Reports Server (NTRS)

Neff, Lily S.; Fleury, Samantha T.; Galazka, Jonathan M.

2018-01-01

Spaceflight imposes multiple stresses on biological systems resulting in genome-scale adaptations. Understanding these adaptations and their underlying molecular mechanisms is important to clarifying and reducing the risks associated with spaceflight. One such risk is infection by microbes present in spacecraft and their associated systems and inhabitants. This risk is compounded by results suggesting that some microbes may exhibit increased virulence after exposure to spaceflight conditions. The yeast, S. cerevisiae, is a powerful microbial model system, and its response to spaceflight has been studied for decades. However, to date, these studies have utilized common lab strains. Yet studies on trait variation in S. cerevisiae demonstrate that these lab strains are not representative of wild yeast and instead respond to environmental stimuli in an atypical manner. Thus, it is not clear how transferable these results are to the wild S. cerevisiae strains likely to be encountered during spaceflight. To determine if diverse S. cerevisiae strains exhibit a conserved response to simulated microgravity, we will utilize a collection of 100 S. cerevisiae strains isolated from clinical, environmental and industrial settings. We will place selected S. cerevisiae strains in simulated microgravity using a high-aspect rotating vessel (HARV) and document their transcriptional response by RNA-sequencing and quantify similarities and differences between strains. Our research will have a strong impact on the understanding of how genetic diversity of microorganisms effects their response to spaceflight, and will serve as a platform for further studies.

Spaceflight and Neurosurgery: A Comprehensive Review of the Relevant Literature.

PubMed

Swinney, Christian C; Allison, Zain

2018-01-01

Spaceflight and the associated gravitational fluctuations may impact various components of the central nervous system. These include changes in intracranial pressure, the spine, and neurocognitive performance. The implications of altered astronaut performance on critical spaceflight missions are potentially significant. The current body of research on this important topic is extremely limited, and a comprehensive review has not been published. Herein, the authors address this notable gap, as well as the role of the neurosurgeon in optimizing potential diagnostic and therapeutic modalities. A literature search was conducted using the PubMed, EMBASE, and Google Scholar databases, with no time constraints. Significant manuscripts on physiologic changes associated with spaceflight and microgravity were identified and reviewed. Manifestations were separated into 1 of 3 general categories, including changes in intracranial pressure, the spine, and neurocognitive performance. A comprehensive literature review yielded 27 studies with direct relevance to the impact of microgravity and spaceflight on nervous system physiology. This included 7 studies related to intracranial pressure fluctuations, 17 related to changes in the spinal column, and 3 related to neurocognitive change. The microgravity environment encountered during spaceflight impacts intracranial physiology. This includes changes in intracranial pressure, the spinal column, and neurocognitive performance. Herein, we present a systematic review of the published literature on this issue. Neurosurgeons should have a key role in the continued study of this important topic, contributing to both diagnostic and therapeutic understanding. Copyright © 2017 Elsevier Inc. All rights reserved.

Spaceflight-induced neuroplasticity in humans as measured by MRI: what do we know so far?

PubMed

Van Ombergen, Angelique; Laureys, Steven; Sunaert, Stefan; Tomilovskaya, Elena; Parizel, Paul M; Wuyts, Floris L

2017-01-01

Space travel poses an enormous challenge on the human body; microgravity, ionizing radiation, absence of circadian rhythm, confinement and isolation are just some of the features associated with it. Obviously, all of the latter can have an impact on human physiology and even induce detrimental changes. Some organ systems have been studied thoroughly under space conditions, however, not much is known on the functional and morphological effects of spaceflight on the human central nervous system. Previous studies have already shown that central nervous system changes occur during and after spaceflight in the form of neurovestibular problems, alterations in cognitive function and sensory perception, cephalic fluid shifts and psychological disturbances. However, little is known about the underlying neural substrates. In this review, we discuss the current limited knowledge on neuroplastic changes in the human central nervous system associated with spaceflight (actual or simulated) as measured by magnetic resonance imaging-based techniques. Furthermore, we discuss these findings as well as their future perspectives, since this can encourage future research into this delicate and intriguing aspect of spaceflight. Currently, the literature suffers from heterogeneous experimental set-ups and therefore, the lack of comparability of findings among studies. However, the cerebellum, cortical sensorimotor and somatosensory areas and vestibular-related pathways seem to be involved across different studies, suggesting that these brain regions are most affected by (simulated) spaceflight. Extending this knowledge is crucial, especially with the eye on long-duration interplanetary missions (e.g. Mars) and space tourism.

Effects of the space flight environment on man's immune system. II - Lymphocyte counts and reactivity.

NASA Technical Reports Server (NTRS)

Fischer, G. L.; Daniels, J. C.; Levin, W. C.; Kimzey, S. L.; Cobb, E. K.; Ritzmann, S. E.

1972-01-01

The present studies were undertaken to assess the effects of the environment of space flights on the cellular division of the human immune system. Peripheral blood absolute lymphocyte counts were determined at various preflight and postflight intervals for the 21 crewmen of Apollo Missions 7-13. Mean lymphocyte numbers tended to exhibit a delayed significant but fluctuating increase shortly after recovery, although a variety of responses was seen in individual astronauts. The in vitro reactivity of lymphocytes, reflected by RNA and DNA synthesis rates by unstimulated and PHA-stimulated lymphocytes tissue-cultured preflight and postflight from the same participants, was found to remain within previously established normal ranges. These results indicate that functional integrity of cellular immune potential as reflected by in vitro techniques is maintained during this spaceflight experience.

Nutrition in space: lessons from the past applied to the future.

PubMed

Lane, H W; Smith, S M; Rice, B L; Bourland, C T

1994-11-01

From the basic impact of nutrient intake on health maintenance to the psychosocial benefits of mealtime, the role of nutrition in space is evident. In this discussion, dietary intake data from three space programs, Apollo, Space Shuttle, and Skylab, are presented. Data examination reveals that energy and fluid intakes are almost always lower than predicted. Nutrition in space has many areas of impact, including provision of required nutrients and maintenance of endocrine, immune, and musculoskeletal systems. Long-duration missions will require quantitation of nutrient requirements for maintenance of health and protection against the effects of microgravity. Psychosocial aspects of nutrition will also be important for more productive missions and crew morale. Realization of the full role of nutrition during spaceflight is critical for the success of extended-duration missions. Research conducted to determine the impact of spaceflight on human physiology and subsequent nutritional requirements will also have direct and indirect applications in Earth-based nutrition research.

Mortality in Severe Human Immunodeficiency Virus-Tuberculosis Associates With Innate Immune Activation and Dysfunction of Monocytes

PubMed Central

Janssen, Saskia; Schutz, Charlotte; Ward, Amy; Nemes, Elisa; Wilkinson, Katalin A; Scriven, James; Huson, Mischa A; Aben, Nanne; Maartens, Gary; Burton, Rosie; Wilkinson, Robert J; Grobusch, Martin P; Van der Poll, Tom; Meintjes, Graeme

2017-01-01

Abstract Background Case fatality rates among hospitalized patients diagnosed with human immunodeficiency virus (HIV)-associated tuberculosis remain high, and tuberculosis mycobacteremia is common. Our aim was to define the nature of innate immune responses associated with 12-week mortality in this population. Methods This prospective cohort study was conducted at Khayelitsha Hospital, Cape Town, South Africa. Hospitalized HIV-infected tuberculosis patients with CD4 counts <350 cells/µL were included; tuberculosis blood cultures were performed in all. Ambulatory HIV-infected patients without active tuberculosis were recruited as controls. Whole blood was stimulated with Escherichia coli derived lipopolysaccharide, heat-killed Streptococcus pneumoniae, and Mycobacterium tuberculosis. Biomarkers of inflammation and sepsis, intracellular (flow cytometry) and secreted cytokines (Luminex), were assessed for associations with 12-week mortality using Cox proportional hazard models. Second, we investigated associations of these immune markers with tuberculosis mycobacteremia. Results Sixty patients were included (median CD4 count 53 cells/µL (interquartile range [IQR], 22–132); 16 (27%) died after a median of 12 (IQR, 0–24) days. Thirty-one (52%) grew M. tuberculosis on blood culture. Mortality was associated with higher concentrations of procalcitonin, activation of the innate immune system (% CD16+CD14+ monocytes, interleukin-6, tumour necrosis factor-ɑ and colony-stimulating factor 3), and antiinflammatory markers (increased interleukin-1 receptor antagonist and lower monocyte and neutrophil responses to bacterial stimuli). Tuberculosis mycobacteremia was not associated with mortality, nor with biomarkers of sepsis. Conclusions Twelve-week mortality was associated with greater pro- and antiinflammatory alterations of the innate immune system, similar to those reported in severe bacterial sepsis. PMID:28369200

Mortality in Severe Human Immunodeficiency Virus-Tuberculosis Associates With Innate Immune Activation and Dysfunction of Monocytes.

PubMed

Janssen, Saskia; Schutz, Charlotte; Ward, Amy; Nemes, Elisa; Wilkinson, Katalin A; Scriven, James; Huson, Mischa A; Aben, Nanne; Maartens, Gary; Burton, Rosie; Wilkinson, Robert J; Grobusch, Martin P; Van der Poll, Tom; Meintjes, Graeme

2017-07-01

Case fatality rates among hospitalized patients diagnosed with human immunodeficiency virus (HIV)-associated tuberculosis remain high, and tuberculosis mycobacteremia is common. Our aim was to define the nature of innate immune responses associated with 12-week mortality in this population. This prospective cohort study was conducted at Khayelitsha Hospital, Cape Town, South Africa. Hospitalized HIV-infected tuberculosis patients with CD4 counts <350 cells/µL were included; tuberculosis blood cultures were performed in all. Ambulatory HIV-infected patients without active tuberculosis were recruited as controls. Whole blood was stimulated with Escherichia coli derived lipopolysaccharide, heat-killed Streptococcus pneumoniae, and Mycobacterium tuberculosis. Biomarkers of inflammation and sepsis, intracellular (flow cytometry) and secreted cytokines (Luminex), were assessed for associations with 12-week mortality using Cox proportional hazard models. Second, we investigated associations of these immune markers with tuberculosis mycobacteremia. Sixty patients were included (median CD4 count 53 cells/µL (interquartile range [IQR], 22-132); 16 (27%) died after a median of 12 (IQR, 0-24) days. Thirty-one (52%) grew M. tuberculosis on blood culture. Mortality was associated with higher concentrations of procalcitonin, activation of the innate immune system (% CD16+CD14+ monocytes, interleukin-6, tumour necrosis factor-ɑ and colony-stimulating factor 3), and antiinflammatory markers (increased interleukin-1 receptor antagonist and lower monocyte and neutrophil responses to bacterial stimuli). Tuberculosis mycobacteremia was not associated with mortality, nor with biomarkers of sepsis. Twelve-week mortality was associated with greater pro- and antiinflammatory alterations of the innate immune system, similar to those reported in severe bacterial sepsis. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

Influence of diabetes mellitus on immunity to human tuberculosis.

PubMed

Kumar Nathella, Pavan; Babu, Subash

2017-09-01

Type 2 diabetes mellitus(DM) is a major risk factor for the development of active pulmonary tuberculosis (TB), with development of DM pandemic in countries where TB is also endemic. Understanding the impact of DM on TB and the determinants of co-morbidity is essential in responding to this growing public health problem with improved therapeutic approaches. Despite the clinical and public health significance posed by the dual burden of TB and DM, little is known about the immunological and biochemical mechanisms of susceptibility. One possible mechanism is that an impaired immune response in patients with DM facilitates either primary infection with Mycobacterium tuberculosis or reactivation of latent TB. Diabetes is associated with immune dysfunction and alterations in the components of the immune system, including altered levels of specific cytokines and chemokines. Some effects of DM on adaptive immunity that are potentially relevant to TB defence have been identified in humans. In this review, we summarize current findings regarding the alterations in the innate and adaptive immune responses and immunological mechanisms of susceptibility of patients with DM to M. tuberculosis infection and disease. © 2017 John Wiley & Sons Ltd.

Tumour necrosis factor receptor trafficking dysfunction opens the TRAPS door to pro-inflammatory cytokine secretion

PubMed Central

Turner, Mark D.; Chaudhry, Anupama; Nedjai, Belinda

2011-01-01

Cytokines are secreted from macrophages and other cells of the immune system in response to pathogens. Additionally, in autoinflammatory diseases cytokine secretion occurs in the absence of pathogenic stimuli. In the case of TRAPS [TNFR (tumour necrosis factor receptor)-associated periodic syndrome], inflammatory episodes result from mutations in the TNFRSF1A gene that encodes TNFR1. This work remains controversial, however, with at least three distinct separate mechanisms of receptor dysfunction having been proposed. Central to these hypotheses are the NF-κB (nuclear factor κB) and MAPK (mitogen-activated protein kinase) families of transcriptional activators that are able to up-regulate expression of a number of genes, including pro-inflammatory cytokines. The present review examines each proposed mechanism of TNFR1 dysfunction, and addresses how these processes might ultimately impact upon cytokine secretion and disease pathophysiology. PMID:22115362

Risk of Performance Decrements and Adverse Health Outcomes Resulting from Sleep Loss, Circadian Desynchronization, and Work Overload

NASA Technical Reports Server (NTRS)

Flynn-Evans, Erin; Gregory, Kevin; Arsintescu, Lucia; Whitmire, Alexandra

2016-01-01

Sleep loss, circadian desynchronization, and work overload occur to some extent for ground and flight crews, prior to and during spaceflight missions. Ground evidence indicates that such risk factors may lead to performance decrements and adverse health outcomes, which could potentially compromise mission objectives. Efforts are needed to identify the environmental and mission conditions that interfere with sleep and circadian alignment, as well as individual differences in vulnerability and resiliency to sleep loss and circadian desynchronization. Specifically, this report highlights a collection of new evidence to better characterize the risk and reveals new gaps in this risk as follows: Sleep loss is apparent during spaceflight. Astronauts consistently average less sleep during spaceflight relative to on the ground. The causes of this sleep loss remain unknown, however ground-based evidence suggests that the sleep duration of astronauts is likely to lead to performance impairment and short and long-term health consequences. Further research is needed in this area in order to develop screening tools to assess individual astronaut sleep need in order to quantify the magnitude of sleep loss during spaceflight; current and planned efforts in BHP's research portfolio address this need. In addition, it is still unclear whether the conditions of spaceflight environment lead to sleep loss or whether other factors, such as work overload lead to the reduced sleep duration. Future data mining efforts and continued data collection on the ISS will help to further characterize factors contributing to sleep loss. Sleep inertia has not been evaluated during spaceflight. Ground-based studies confirm that it takes two to four hours to achieve optimal performance after waking from a sleep episode. Sleep inertia has been associated with increased accidents and reduced performance in operational environments. Sleep inertia poses considerable risk during spaceflight when emergency situations necessitate that crewmembers wake from sleep and make quick decisions. A recently completed BHP investigation assesses the effects of sleep inertia upon abrupt awakening, with and without hypnotics currently used in spaceflight; results from this investigation will help to inform strategies relative to sleep inertia effects on performance. Circadian desynchrony has been observed during spaceflight. Circadian desynchrony during spaceflight develops due to schedule constraints requiring non-24 operations or 'slam-shifts' and due to insufficient or mis-timed light exposure. In addition, circadian misalignment has been associated with reduced sleep duration and increased medication use. In ground-based studies, circadian desynchrony has been associated with significant performance impairment and increased risk of accidents when operations coincide with the circadian nadir. There is a great deal of information available on how to manage circadian misalignment, however, there are currently no easily collected biomarkers that can be used during spaceflight to determine circadian phase. Current research efforts are addressing this gap. Work overload has been documented during current spaceflight operations. NASA has established work hour guidelines that limit shift duration, however, schedule creep, where duty requirements necessitate working beyond scheduled work hours, has been reported. This observation warrants the documentation of actual work hours in order to improve planning and in order to ensure that astronauts receive adequate down time. In addition to concerns about work overload, ground based evidence suggests that work underload may be a concern during deep space missions, where torpor may develop and physically demanding workload will be exchanged for monitoring of autonomous systems. Given that increased automation is anticipated for exploration vehicles, fatigue effects in the context of such systems needs to be further understood. Performance metrics are needed to evaluate fitness-for-duty during spaceflight. Although ground-based evidence supports the notion that sleep loss, circadian desynchronization and work overload lead to performance impairment, inconsistency in the measures used to evaluate performance during spaceflight make it difficult to evaluate the magnitude of performance impairment during spaceflight. Work is underway to standardize measures of performance evaluation during spaceflight. Once established, such performance indicators need to be correlated with operational performance. Individual differences in sleep need and circadian preference, phase shifting ability and period have been documented in ground-based studies. Individual differences in response to sleep loss and circadian misalignment have also been documented and are presumed to be associated with genetic polymorphisms. No studies have systematically reported individual differences in sleep or circadian-related outcomes during spaceflight. More work is needed in this area in order to identify genetic or phenotypic biomarkers that predict resilience or vulnerability to sleep loss in order to personalize countermeasure strategies and mitigate performance impairment during spaceflight. Two laboratory and field investigations specific to this topic are currently ongoing; additional efforts, including an effort to mine existing biological data from spaceflight relative to sleep and circadian outcomes, are planned. Sex differences in sleep need and circadian period and phase have been reported in ground-based studies. The impact of these sex differences on performance is unclear. Sex differences in sleep need and circadian rhythms have not been systematically studied during spaceflight, presumably due to the small number of women that have flown in space. More research is needed in this area to evaluate whether any of the observed sex differences in physiology lead to altered performance in spaceflight and on the ground.

The challenging environment on board the International Space Station affects endothelial cell function by triggering oxidative stress through thioredoxin interacting protein overexpression: the ESA-SPHINX experiment.

PubMed

Versari, Silvia; Longinotti, Giulia; Barenghi, Livia; Maier, Jeanette Anne Marie; Bradamante, Silvia

2013-11-01

Exposure to microgravity generates alterations that are similar to those involved in age-related diseases, such as cardiovascular deconditioning, bone loss, muscle atrophy, and immune response impairment. Endothelial dysfunction is the common denominator. To shed light on the underlying mechanism, we participated in the Progress 40P mission with Spaceflight of Human Umbilical Vein Endothelial Cells (HUVECs): an Integrated Experiment (SPHINX), which consisted of 12 in-flight and 12 ground-based control modules and lasted 10 d. Postflight microarray analysis revealed 1023 significantly modulated genes, the majority of which are involved in cell adhesion, oxidative phosphorylation, stress responses, cell cycle, and apoptosis. Thioredoxin-interacting protein was the most up-regulated (33-fold), heat-shock proteins 70 and 90 the most down-regulated (5.6-fold). Ion channels (TPCN1, KCNG2, KCNJ14, KCNG1, KCNT1, TRPM1, CLCN4, CLCA2), mitochondrial oxidative phosphorylation, and focal adhesion were widely affected. Cytokine detection in the culture media indicated significant increased secretion of interleukin-1α and interleukin-1β. Nitric oxide was found not modulated. Our data suggest that in cultured HUVECs, microgravity affects the same molecular machinery responsible for sensing alterations of flow and generates a prooxidative environment that activates inflammatory responses, alters endothelial behavior, and promotes senescence.

NASA's human system risk management approach and its applicability to commercial spaceflight.

PubMed

Law, Jennifer; Mathers, Charles H; Fondy, Susan R E; Vanderploeg, James M; Kerstman, Eric L

2013-01-01

As planning continues for commercial spaceflight, attention is turned to NASA to assess whether its human system risk management approach can be applied to mitigate the risks associated with commercial suborbital and orbital flights. NASA uses a variety of methods to assess the risks to the human system based on their likelihood and consequences. In this article, we review these methods and categorize the risks in the system as "definite," "possible," or "least" concern for commercial spaceflight. As with career astronauts, these risks will be primarily mitigated by screening and environmental control. Despite its focus on long-duration exploration missions, NASA's human system risk management approach can serve as a preliminary knowledge base to help medical planners prepare for commercial spaceflights.

BP180 dysfunction triggers spontaneous skin inflammation in mice.

PubMed

Zhang, Yang; Hwang, Bin-Jin; Liu, Zhen; Li, Ning; Lough, Kendall; Williams, Scott E; Chen, Jinbo; Burette, Susan W; Diaz, Luis A; Su, Maureen A; Xiao, Shengxiang; Liu, Zhi

2018-06-04

BP180, also known as collagen XVII, is a hemidesmosomal component and plays a key role in maintaining skin dermal/epidermal adhesion. Dysfunction of BP180, either through genetic mutations in junctional epidermolysis bullosa (JEB) or autoantibody insult in bullous pemphigoid (BP), leads to subepidermal blistering accompanied by skin inflammation. However, whether BP180 is involved in skin inflammation remains unknown. To address this question, we generated a BP180-dysfunctional mouse strain and found that mice lacking functional BP180 (termed Δ NC16A ) developed spontaneous skin inflammatory disease, characterized by severe itch, defective skin barrier, infiltrating immune cells, elevated serum IgE levels, and increased expression of thymic stromal lymphopoietin (TSLP). Severe itch is independent of adaptive immunity and histamine, but dependent on increased expression of TSLP by keratinocytes. In addition, a high TSLP expression is detected in BP patients. Our data provide direct evidence showing that BP180 regulates skin inflammation independently of adaptive immunity, and BP180 dysfunction leads to a TSLP-mediated itch. The newly developed mouse strain could be a model for elucidation of disease mechanisms and development of novel therapeutic strategies for skin inflammation and BP180-related skin conditions.

Spaceflight exposure effects on transcription, activity, and localization of alcohol dehydrogenase in the roots of Arabidopsis thaliana.

PubMed Central

Porterfield, D M; Matthews, S W; Daugherty, C J; Musgrave, M E

1997-01-01

Although considerable research and speculation have been directed toward understanding a plant's perception of gravity and the resulting gravitropic responses, little is known about the role of gravity-dependent physical processes in normal physiological function. These studies were conducted to determine whether the roots of plants exposed to spaceflight conditions may be experiencing hypoxia. Arabidopsis thaliana (L.) Heynh. plants were grown in agar medium during 6 or 11 d of spaceflight exposure on shuttle missions STS-54 (CHROMEX-03) and STS-68 (CHROMEX-05), respectively. The analysis included measurement of agar redox potential and root alcohol dehydrogenase (ADH) activity, localization, and expression. ADH activity increased by 89% as a result of spaceflight exposure for both CHROMEX-03 and -05 experiments, and ADH RNase protection assays revealed a 136% increase in ADH mRNA. The increase in ADH activity associated with the spaceflight roots was realized by a 28% decrease in oxygen availability in a ground-based study; however, no reduction in redox potential was observed in measurements of the spaceflight bulk agar. Spaceflight exposure appears to effect a hypoxic response in the roots of agar-grown plants that may be caused by changes in gravity-mediated fluid and/or gas behavior. PMID:9085569

Spaceflight exposure effects on transcription, activity, and localization of alcohol dehydrogenase in the roots of Arabidopsis thaliana

NASA Technical Reports Server (NTRS)

Porterfield, D. M.; Matthews, S. W.; Daugherty, C. J.; Musgrave, M. E.

1997-01-01

Although considerable research and speculation have been directed toward understanding a plant's perception of gravity and the resulting gravitropic responses, little is known about the role of gravity-dependent physical processes in normal physiological function. These studies were conducted to determine whether the roots of plants exposed to spaceflight conditions may be experiencing hypoxia. Arabidopsis thaliana (L.) Heynh. plants were grown in agar medium during 6 or 11 d of spaceflight exposure on shuttle missions STS-54 (CHROMEX-03) and STS-68 (CHROMEX-05), respectively. The analysis included measurement of agar redox potential and root alcohol dehydrogenase (ADH) activity, localization, and expression. ADH activity increased by 89% as a result of spaceflight exposure for both CHROMEX-03 and -05 experiments, and ADH RNase protection assays revealed a 136% increase in ADH mRNA. The increase in ADH activity associated with the spaceflight roots was realized by a 28% decrease in oxygen availability in a ground-based study; however, no reduction in redox potential was observed in measurements of the spaceflight bulk agar. Spaceflight exposure appears to effect a hypoxic response in the roots of agar-grown plants that may be caused by changes in gravity-mediated fluid and/or gas behavior.

CARD9 knockout ameliorates myocardial dysfunction associated with high fat diet-induced obesity.

PubMed

Cao, Li; Qin, Xing; Peterson, Matthew R; Haller, Samantha E; Wilson, Kayla A; Hu, Nan; Lin, Xin; Nair, Sreejayan; Ren, Jun; He, Guanglong

2016-03-01

Obesity is associated with chronic inflammation which plays a critical role in the development of cardiovascular dysfunction. Because the adaptor protein caspase recruitment domain-containing protein 9 (CARD9) in macrophages regulates innate immune responses via activation of pro-inflammatory cytokines, we hypothesize that CARD9 mediates the pro-inflammatory signaling associated with obesity en route to myocardial dysfunction. C57BL/6 wild-type (WT) and CARD9(-/-) mice were fed normal diet (ND, 12% fat) or a high fat diet (HFD, 45% fat) for 5months. At the end of 5-month HFD feeding, cardiac function was evaluated using echocardiography. Cardiomyocytes were isolated and contractile properties were measured. Immunofluorescence was performed to detect macrophage infiltration in the heart. Heart tissue homogenates, plasma, and supernatants from isolated macrophages were collected to measure the concentrations of pro-inflammatory cytokines using ELISA kits. Western immunoblotting analyses were performed on heart tissue homogenates and isolated macrophages to explore the underlying signaling mechanism(s). CARD9 knockout alleviated HFD-induced insulin resistance and glucose intolerance, prevented myocardial dysfunction with preserved cardiac fractional shortening and cardiomyocyte contractile properties. CARD9 knockout also significantly decreased the number of infiltrated macrophages in the heart with reduced myocardium-, plasma-, and macrophage-derived cytokines including IL-6, IL-1β and TNFα. Finally, CARD9 knockout abrogated the increase of p38 MAPK phosphorylation, the decrease of LC3BII/LC3BI ratio and the up-regulation of p62 expression in the heart induced by HFD feeding and restored cardiac autophagy signaling. In conclusion, CARD9 knockout ameliorates myocardial dysfunction associated with HFD-induced obesity, potentially through reduction of macrophage infiltration, suppression of p38 MAPK phosphorylation, and preservation of autophagy in the heart. Copyright © 2016 Elsevier Ltd. All rights reserved.

Innate Immune Signalling Genetics of Pain, Cognitive Dysfunction and Sickness Symptoms in Cancer Pain Patients Treated with Transdermal Fentanyl

PubMed Central

Barratt, Daniel T.; Klepstad, Pål; Dale, Ola; Kaasa, Stein; Somogyi, Andrew A.

2015-01-01

Common adverse symptoms of cancer and chemotherapy are a major health burden; chief among these is pain, with opioids including transdermal fentanyl the mainstay of treatment. Innate immune activation has been implicated generally in pain, opioid analgesia, cognitive dysfunction, and sickness type symptoms reported by cancer patients. We aimed to determine if genetic polymorphisms in neuroimmune activation pathways alter the serum fentanyl concentration-response relationships for pain control, cognitive dysfunction, and other adverse symptoms, in cancer pain patients. Cancer pain patients (468) receiving transdermal fentanyl were genotyped for 31 single nucleotide polymorphisms in 19 genes: CASP1, BDNF, CRP, LY96, IL6, IL1B, TGFB1, TNF, IL10, IL2, TLR2, TLR4, MYD88, IL6R, OPRM1, ARRB2, COMT, STAT6 and ABCB1. Lasso and backward stepwise generalised linear regression were used to identify non-genetic and genetic predictors, respectively, of pain control (average Brief Pain Inventory < 4), cognitive dysfunction (Mini-Mental State Examination ≤ 23), sickness response and opioid adverse event complaint. Serum fentanyl concentrations did not predict between-patient variability in these outcomes, nor did genetic factors predict pain control, sickness response or opioid adverse event complaint. Carriers of the MYD88 rs6853 variant were half as likely to have cognitive dysfunction (11/111) than wild-type patients (69/325), with a relative risk of 0.45 (95% CI: 0.27 to 0.76) when accounting for major non-genetic predictors (age, Karnofsky functional score). This supports the involvement of innate immune signalling in cognitive dysfunction, and identifies MyD88 signalling pathways as a potential focus for predicting and reducing the burden of cognitive dysfunction in cancer pain patients. PMID:26332828

Hepatocyte growth factor limits autoimmune neuroinflammation via glucocorticoid-induced leucine zipper expression in dendritic cells.

PubMed

Benkhoucha, Mahdia; Molnarfi, Nicolas; Dunand-Sauthier, Isabelle; Merkler, Doron; Schneiter, Gregory; Bruscoli, Stefano; Riccardi, Carlo; Tabata, Yasuhiko; Funakoshi, Hiroshi; Nakamura, Toshikazu; Reith, Walter; Santiago-Raber, Marie-Laure; Lalive, Patrice H

2014-09-15

Autoimmune neuroinflammation, including multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE), a prototype for T cell-mediated autoimmunity, is believed to result from immune tolerance dysfunction leading to demyelination and substantial neurodegeneration. We previously showed that CNS-restricted expression of hepatocyte growth factor (HGF), a potent neuroprotective factor, reduced CNS inflammation and clinical deficits associated with EAE. In this study, we demonstrate that systemic HGF treatment ameliorates EAE through the development of tolerogenic dendritic cells (DCs) with high expression levels of glucocorticoid-induced leucine zipper (GILZ), a transcriptional repressor of gene expression and a key endogenous regulator of the inflammatory response. RNA interference-directed neutralization of GILZ expression by DCs suppressed the induction of tolerance caused by HGF. Finally, adoptive transfer of HGF-treated DCs from wild-type but not GILZ gene-deficient mice potently mediated functional recovery in recipient mice with established EAE through effective modulation of autoaggressive T cell responses. Altogether, these results show that by inducing GILZ in DCs, HGF reproduces the mechanism of immune regulation induced by potent immunomodulatory factors such as IL-10, TGF-β1, and glucocorticoids and therefore that HGF therapy may have potential in the treatment of autoimmune dysfunctions. Copyright © 2014 by The American Association of Immunologists, Inc.

Neutrophil depletion after subarachnoid hemorrhage improves memory via NMDA receptors.

PubMed

Provencio, Jose Javier; Swank, Valerie; Lu, Haiyan; Brunet, Sylvain; Baltan, Selva; Khapre, Rohini V; Seerapu, Himabindu; Kokiko-Cochran, Olga N; Lamb, Bruce T; Ransohoff, Richard M

2016-05-01

Cognitive deficits after aneurysmal subarachnoid hemorrhage (SAH) are common and disabling. Patients who experience delayed deterioration associated with vasospasm are likely to have cognitive deficits, particularly problems with executive function, verbal and spatial memory. Here, we report neurophysiological and pathological mechanisms underlying behavioral deficits in a murine model of SAH. On tests of spatial memory, animals with SAH performed worse than sham animals in the first week and one month after SAH suggesting a prolonged injury. Between three and six days after experimental hemorrhage, mice demonstrated loss of late long-term potentiation (L-LTP) due to dysfunction of the NMDA receptor. Suppression of innate immune cell activation prevents delayed vasospasm after murine SAH. We therefore explored the role of neutrophil-mediated innate inflammation on memory deficits after SAH. Depletion of neutrophils three days after SAH mitigates tissue inflammation, reverses cerebral vasoconstriction in the middle cerebral artery, and rescues L-LTP dysfunction at day 6. Spatial memory deficits in both the short and long-term are improved and associated with a shift of NMDA receptor subunit composition toward a memory sparing phenotype. This work supports further investigating suppression of innate immunity after SAH as a target for preventative therapies in SAH. Copyright © 2016 Elsevier Inc. All rights reserved.

Statistical Challenges in Biomedical Research

NASA Technical Reports Server (NTRS)

Feiveson, Alan H.; Ploutz-Snyder, Rob; Fiedler, James

2010-01-01

Potentially debilitating effects of spaceflight environment include: a) Bone Demineralization - Osteoporosis. b)Impaired Fracture Healing - Non-Union. c) Renal Stone Formation & Soft Tissue Calcification. d) Orthostatic Intolerance (on return to gravity). e) Cardiac Arrhythmias. f) Dehydration (on return to gravity). g) Decreased Aerobic Capacity. h) Impaired Coordination. i) Muscle Atrophy (Loss of Strength). j) Radiation Sickness. k) Increased Cancer Risk. l) Impaired Immune Function. m) Behavioral Changes & Performance Decrements n) Altitude Decompression Sickness during EVA.

Paradoxical aging in HIV: immune senescence of B Cells is most prominent in young age.

PubMed

Rinaldi, Stefano; Pallikkuth, Suresh; George, Varghese K; de Armas, Lesley R; Pahwa, Rajendra; Sanchez, Celeste M; Pallin, Maria Fernanda; Pan, Li; Cotugno, Nicola; Dickinson, Gordon; Rodriguez, Allan; Fischl, Margaret; Alcaide, Maria; Gonzalez, Louis; Palma, Paolo; Pahwa, Savita

2017-04-01

Combination antiretroviral therapies (cART)can lead to normal life expectancy in HIV-infected persons, and people aged >50 yrs represent the fastest growing HIV group. Although HIV and aging are independently associated with impaired humoral immunity, immune status in people aging with HIV is relatively unexplored. In this study influenza vaccination was used to probe age associated perturbations in the B cell compartment of HIV-negative "healthy controls" (HC) and virologically controlled HIV-infected participants on cART (HIV) (n=124), grouped by age as young (<40 yrs), middle-aged (40-59yrs) or old ( > 60 yrs). H1N1 antibody response at d21 post-vaccination correlated inversely with age in both HC and HIV. Immunophenotyping of cryopreserved PBMC demonstrated increased frequencies of double negative B cells and decreased plasmablasts in old compared to young HC. Remarkably, young HIV were different from young HC but similar to old HC in B cell phenotype, influenza specific spontaneous (d7) or memory (d21) antibody secreting cells. We conclude that B cell immune senescence is a prominent phenomenon in young HIV in comparison to young HC, but distinctions between old HIV and old HC are less evident though both groups manifest age-associated B cell dysfunction.

Paradoxical aging in HIV: immune senescence of B Cells is most prominent in young age

PubMed Central

George, Varghese K.; de Armas, Lesley R.; Pahwa, Rajendra; Sanchez, Celeste M.; Pallin, Maria Fernanda; Pan, Li; Cotugno, Nicola; Dickinson, Gordon; Rodriguez, Allan; Fischl, Margaret; Alcaide, Maria; Gonzalez, Louis; Palma, Paolo; Pahwa, Savita

2017-01-01

Combination antiretroviral therapies (cART) can lead to normal life expectancy in HIV-infected persons, and people aged >50 yrs represent the fastest growing HIV group. Although HIV and aging are independently associated with impaired humoral immunity, immune status in people aging with HIV is relatively unexplored. In this study influenza vaccination was used to probe age associated perturbations in the B cell compartment of HIV-negative “healthy controls” (HC) and virologically controlled HIV-infected participants on cART (HIV) (n=124), grouped by age as young (<40 yrs), middle-aged (40-59yrs) or old (≥60 yrs). H1N1 antibody response at d21 post-vaccination correlated inversely with age in both HC and HIV. Immunophenotyping of cryopreserved PBMC demonstrated increased frequencies of double negative B cells and decreased plasmablasts in old compared to young HC. Remarkably, young HIV were different from young HC but similar to old HC in B cell phenotype, influenza specific spontaneous (d7) or memory (d21) antibody secreting cells. We conclude that B cell immune senescence is a prominent phenomenon in young HIV in comparison to young HC, but distinctions between old HIV and old HC are less evident though both groups manifest age-associated B cell dysfunction. PMID:28448963

Subclinical Shed of Infectious Varicella zoster Virus in Astronauts

NASA Technical Reports Server (NTRS)

Cohrs, Randall J.; Mehta, Satish K.; Schmid, D. Scott; Gilden, Donald H.; Pierson, Duane L.

2007-01-01

Aerosol borne varicella zoster virus (VZV) enters the nasopharynx and replicates in tonsillar T-cells, resulting in viremia and varicella (chickenpox). Virus then becomes latent in cranial nerve, dorsal root and autonomic nervous system ganglia along the entire neuraxis (1). Decades later, as cell-mediated immunity to VZV declines (4), latent VZV can reactivate to produce zoster (shingles). Infectious VZV is present in patients with varicella or zoster, but shed of infectious virus in the absence of disease has not been shown. We previously detected VZV DNA in saliva of astronauts during and shortly after spaceflight, suggesting stress induced subclinical virus reactivation (3). We show here that VZV DNA as well as infectious virus in present in astronaut saliva. VZV DNA was detected in saliva during and after a 13-day spaceflight in 2 of 3 astronauts (Fig. panel A). Ten days before liftoff, there was a rise in serum anti-VZV antibody in subjects 1 and 2, consistent with virus reactivation. In subject 3, VZV DNA was not detected in saliva, and there was no rise in anti-VZV antibody titer. Subject 3 may have been protected from virus reactivation by having zoster <10 years ago, which provides a boost in cell-medicated immunity to VZV (2). No VZV DNA was detected in astronaut saliva months before spaceflight, or in saliva of 10 age/sex-matched healthy control subjects sampled on alternate days for 3 weeks (88 saliva samples). Saliva taken 2-6 days after landing from all 3 subjects was cultured on human fetal lung cells (Fig. panel B). Infectious VZV was recovered from saliva of subjects 1 and 2 on the second day after landing. Virus specificity was confirmed by antibody staining and DNA analysis which showed it to be VZV of European descent, common in the US (5). Further, both antibody staining and DNA PCR demonstrated that no HSV-1 was detected in any infected culture. This is the first report of infectious VZV shedding in the absence of clinical disease. Spaceflight presents a uniquely stressful environment which includes physical isolation and confinement, anxiety, sleep deprivation, as well as exposure to increased radiation and microgravity. It is interesting that in our study, VZV and not HSV-1 reactivation was detected, since stress-induced HSV-1 reactivation has been reported (6). Future studies are needed to determine the specific inducer of VZV reactivation.

Identification and Evaluation of Integration and Cross Cutting Issues Across HRP Risks

NASA Technical Reports Server (NTRS)

Steinberg, S. L.; Shelhamer, Mark

2015-01-01

The HRP Integrated Research Plan contains the research plans for the 32 risks requiring research to characterize and mitigate. These risks to human health and performance in spaceflight are identified by evidence and each one focuses on a single aspect of human physiology or performance. They are further categorized by aspects of the spaceflight environment, such as altered gravity or space radiation, that that play a major role in their likelihood and consequence. From its inception the "integrate" in the Research Plan has denoted the integrated nature of risks to human health and performance, the connectedness of physiological systems within the human body regardless of the spaceflight environment, and the integrated response of the human body to the spaceflight environment. Common characteristics of the spaceflight environment include altered gravity, atmospheres and light/dark cycles, space radiation, isolation, noise, and periods of high or low workload. Long term exposure to this unique environment produces a suite of physiological effects such as stress; vision, neurocognitive and anthropometric changes; circadian misalignment; fluid shifts, deconditioning; immune dysregulation; and altered nutritional requirements. Matrix diagraming was used to systematically identify, analyze and rate the many-to-many relationships between environmental characteristics and the suite of physiological effects. It was also to identify patterns in the relationships of common physiological effects to each other. Analyses of patterns or relationships in these diagrams help to identify issues that cut across multiple risks. Cross cutting issues benefit from a multidisciplinary approach that synthesizes concepts or data from two or more disciplines to identify and characterize risk factors or develop countermeasures relevant to multiple risks. They also help to illuminate possible problem areas that may arise when a countermeasure impacts risks other than those which it was developed to mitigate, or identify groupings of physiological changes that are likely to occur that may impact the overall risk posture.

The effects of spaceflight and Insulin-like Growth Factor-1 on the T-cell and macrophage populations

NASA Astrophysics Data System (ADS)

Pecaut, Michael J.; Simske, Steve J.; Fleshner, Monika; Zimmerman, Robert

1997-01-01

Twelve Sprague-Dawley rats were flown aboard the Space Shuttle Endeavor (STS-77) to study the effects of microgravity-induced stress on the immunoskeletal system. Sixteen rats were used as simultaneous vivarium ground controls during the ten day mission. Osmotic pumps, half of which contained Insulin-like Growth Factor-1 (IGF-1, provided by Chiron), were surgically implanted (subcutaneous) into the rats prior to launch in an attempt to counter any stress effects. On the day of landing, the rats were sacrificed and dissected. Splenocytes and thymocytes were labeled with antibodies against CD4, CD8, CD11b, and TCR for flow cytometry. The percentage of splenic cytotoxic/suppressor (TCR+/CD8+) T-cells increased significantly (by 118%) in spaceflight. There were also decreases in splenic helper (TCR+/CD4+) T-cells and (CD11b+) macrophages (by 33% and 38%, respectively). Together, these results suggest the stress of spaceflight could cause a significant decrease in the ability of rats to mount an immune response. The effects of IGF-1 on cell population distributions were negligible for both flight and vivarium ground controls. However, there were significant differences in spleen and thymus masses suggesting that while IGF-1 did not effect population distributions, the drug may have caused an increase in population size.

Old Maids: Aging and Its Impact on Microglia Function

PubMed Central

Koellhoffer, Edward C.; McCullough, Louise D.; Ritzel, Rodney M.

2017-01-01

Microglia are highly active and vigilant housekeepers of the central nervous system that function to promote neuronal growth and activity. With advanced age, however, dysregulated inflammatory signaling and defects in phagocytosis impede their ability to perform the most essential of homeostatic functions, including immune surveillance and debris clearance. Microglial activation is one of the hallmarks of the aging brain and coincides with age-related neurodegeneration and cognitive decline. Age-associated microglial dysfunction leads to cellular senescence and can profoundly alter the response to sterile injuries and immune diseases, often resulting in maladaptive responses, chronic inflammation, and worsened outcomes after injury. Our knowledge of microglia aging and the factors that regulate age-related microglial dysfunction remain limited, as the majority of pre-clinical studies are performed in young animals, and human brain samples are difficult to obtain quickly post-mortem or in large numbers. This review outlines the impact of normal aging on microglial function, highlights the potential mechanisms underlying age-related changes in microglia, and discusses how aging can shape the recovery process following injury. PMID:28379162

Natural Killer Cell Function and Dysfunction in Hepatitis C Virus Infection

PubMed Central

Holder, Kayla A.; Russell, Rodney S.; Grant, Michael D.

2014-01-01

Viruses must continually adapt against dynamic innate and adaptive responses of the host immune system to establish chronic infection. Only a small minority (~20%) of those exposed to hepatitis C virus (HCV) spontaneously clear infection, leaving approximately 200 million people worldwide chronically infected with HCV. A number of recent research studies suggest that establishment and maintenance of chronic HCV infection involve natural killer (NK) cell dysfunction. This relationship is illustrated in vitro by disruption of typical NK cell responses including both cell-mediated cytotoxicity and cytokine production. Expression of a number of activating NK cell receptors in vivo is also affected in chronic HCV infection. Thus, direct in vivo and in vitro evidence of compromised NK function in chronic HCV infection in conjunction with significant epidemiological associations between the outcome of HCV infection and certain combinations of NK cell regulatory receptor and class I human histocompatibility linked antigen (HLA) genotypes indicate that NK cells are important in the immune response against HCV infection. In this review, we highlight evidence suggesting that selective impairment of NK cell activity is related to establishment of chronic HCV infection. PMID:25057504

Environment enrichment rescues the neurodegenerative phenotypes in presenilins-deficient mice.

PubMed

Dong, Suzhen; Li, Chunxia; Wu, Pu; Tsien, Joe Z; Hu, Yinghe

2007-07-01

Presenilin (PS) 1 and 2 conditional double knockout (cDKO) mice show progressive memory dysfunction and forebrain degeneration. Gene expression profiling results revealed a strong activation of immunity and inflammation responses in the brains of 10-month-old cDKO mice. As environmental enrichment (EE) has been shown to be able to improve memory and induce neurogenesis of the brain, we assessed the effects of EE on the memory performance and the neurodegeneration in cDKO mice. We found that EE effectively enhanced memory and partially rescued the forebrain atrophy of the cDKO mice. Our results suggest that immunity and inflammation could play important roles in the neurodegeneration of cDKO mice. Furthermore, the beneficial effects of EE may be associated with the inhibition of the expression of immunity and inflammation-related genes in the brain.

Acute disseminated encephalomyelitis in dengue viral infection.

PubMed

Wan Sulaiman, Wan Aliaa; Inche Mat, Liyana Najwa; Hashim, Hasnur Zaman; Hoo, Fan Kee; Ching, Siew Mooi; Vasudevan, Ramachandran; Mohamed, Mohd Hazmi; Basri, Hamidon

2017-09-01

Dengue is the most common arboviral disease affecting many countries worldwide. An RNA virus from the flaviviridae family, dengue has four antigenically distinct serotypes (DEN-1-DEN-4). Neurological involvement in dengue can be classified into dengue encephalopathy immune-mediated syndromes, encephalitis, neuromuscular or dengue muscle dysfunction and neuro-ophthalmic involvement. Acute disseminated encephalomyelitis (ADEM) is an immune mediated acute demyelinating disorder of the central nervous system following recent infection or vaccination. This monophasic illness is characterised by multifocal white matter involvement. Many dengue studies and case reports have linked ADEM with dengue virus infection but the association is still not clear. Therefore, this article is to review and discuss concerning ADEM in dengue as an immune-medicated neurological complication; and the management strategy required based on recent literature. Copyright © 2017 Elsevier Ltd. All rights reserved.

Altered Methylation Profile of Lymphocytes Is Concordant with Perturbation of Lipids Metabolism and Inflammatory Response in Obesity

PubMed Central

Jacobsen, Mette J.; Mentzel, Caroline M. Junker; Olesen, Ann Sofie; Huby, Thierry; Jørgensen, Claus B.; Barrès, Romain; Fredholm, Merete

2016-01-01

Obesity is associated with immunological perturbations that contribute to insulin resistance. Epigenetic mechanisms can control immune functions and have been linked to metabolic complications, although their contribution to insulin resistance still remains unclear. In this study, we investigated the link between metabolic dysfunction and immune alterations with the epigenetic signature in leukocytes in a porcine model of obesity. Global DNA methylation of circulating leukocytes, adipose tissue leukocyte trafficking, and macrophage polarisation were established by flow cytometry. Adipose tissue inflammation and metabolic function were further characterised by quantification of metabolites and expression levels of genes associated with obesity and inflammation. Here we show that obese pigs showed bigger visceral fat pads, higher levels of circulating LDL cholesterol, and impaired glucose tolerance. These changes coincided with impaired metabolism, sustained macrophages infiltration, and increased inflammation in the adipose tissue. Those immune alterations were linked to global DNA hypermethylation in both B-cells and T-cells. Our results provide novel insight into the possible contribution of immune cell epigenetics into the immunological disturbances observed in obesity. The dramatic changes in the transcriptomic and epigenetic signature of circulating lymphocytes reinforce the concept that epigenetic processes participate in the increased immune cell activation and impaired metabolic functions in obesity. PMID:26798656

Stimulation of dendritic cells enhances immune response after photodynamic therapy

NASA Astrophysics Data System (ADS)

Mroz, Pawel; Castano, Ana P.; Hamblin, Michael R.

2009-02-01

Photodynamic therapy (PDT) involves the administration of photosensitizers followed by illumination of the primary tumor with red light producing reactive oxygen species that cause vascular shutdown and tumor cell necrosis and apoptosis. Anti-tumor immunity is stimulated after PDT due to the acute inflammatory response, priming of the immune system to recognize tumor-associated antigens (TAA). The induction of specific CD8+ Tlymphocyte cells that recognize major histocompatibility complex class I (MHC-I) restricted epitopes of TAAs is a highly desirable goal in cancer therapy. The PDT killed tumor cells may be phagocytosed by dendritic cells (DC) that then migrate to draining lymph nodes and prime naÃve T-cells that recognize TAA epitopes. This process is however, often sub-optimal, in part due to tumor-induced DC dysfunction. Instead of DC that can become mature and activated and have a potent antigen-presenting and immune stimulating phenotype, immature dendritic cells (iDC) are often found in tumors and are part of an immunosuppressive milieu including regulatory T-cells and immunosuppressive cytokines such as TGF-beta and IL10. We here report on the use of a potent DC activating agent, an oligonucleotide (ODN) that contains a non-methylated CpG motif and acts as an agonist of toll like receptor (TLR) 9. TLR activation is a danger signal to notify the immune system of the presence of invading pathogens. CpG-ODN (but not scrambled non-CpG ODN) increased bone-marrow DC activation after exposure to PDT-killed tumor cells, and significantly increased tumor response to PDT and mouse survival after peri-tumoral administration. CpG may be a valuable immunoadjuvant to PDT especially for tumors that produce DC dysfunction.

Higher frequencies of GARP(+)CTLA-4(+)Foxp3(+) T regulatory cells and myeloid-derived suppressor cells in hepatocellular carcinoma patients are associated with impaired T-cell functionality.

PubMed

Kalathil, Suresh; Lugade, Amit A; Miller, Austin; Iyer, Renuka; Thanavala, Yasmin

2013-04-15

The extent to which T-cell-mediated immune surveillance is impaired in human cancer remains a question of major importance, given its potential impact on the development of generalized treatments of advanced disease where the highest degree of heterogeneity exists. Here, we report the first global analysis of immune dysfunction in patients with advanced hepatocellular carcinoma (HCC). Using multi-parameter fluorescence-activated cell sorting analysis, we quantified the cumulative frequency of regulatory T cells (Treg), exhausted CD4(+) helper T cells, and myeloid-derived suppressor cells (MDSC) to gain concurrent views on the overall level of immune dysfunction in these inoperable patients. We documented augmented numbers of Tregs, MDSC, PD-1(+)-exhausted T cells, and increased levels of immunosuppressive cytokines in patients with HCC, compared with normal controls, revealing a network of potential mechanisms of immune dysregulation in patients with HCC. In dampening T-cell-mediated antitumor immunity, we hypothesized that these processes may facilitate HCC progression and thwart the efficacy of immunotherapeutic interventions. In testing this hypothesis, we showed that combined regimens to deplete Tregs, MDSC, and PD-1(+) T cells in patients with advanced HCC restored production of granzyme B by CD8(+) T cells, reaching levels observed in normal controls and also modestly increased the number of IFN-γ producing CD4(+) T cells. These clinical findings encourage efforts to restore T-cell function in patients with advanced stage disease by highlighting combined approaches to deplete endogenous suppressor cell populations that can also expand effector T-cell populations. ©2013 AACR.

Spaceflight alters autonomic regulation of arterial pressure in humans

NASA Technical Reports Server (NTRS)

Fritsch-Yelle, Janice M.; Charles, John B.; Jones, Michele M.; Beightol, Larry A.; Eckberg, Dwain L.

1994-01-01

Spaceflight is associated with decreased orthostatic tolerance after landing. Short-duration spaceflight (4 - 5 days) impairs one neutral mechanism: the carotid baroreceptor-cardiac reflex. To understand the effects of longer-duration spaceflight on baroreflex function, we measured R-R interval power spectra, antecubital vein plasma catecholamine levels, carotid baroreceptor-cardiac reflex responses, responses to Valsalva maneuvers, and orthostatic tolerance in 16 astronauts before and after shuttle missions lasting 8 - 14 days. We found the following changes between preflight and landing day: (1) orthostatic tolerance decreased; (2) R-R interval spectral power in the 0.05- to 0.15-Hz band increased; (3) plasma norepinephrine and epinephrine levels increased; (4) the slope, range, and operational point of the carotid baroreceptor cardiac reflex response decreased; and (5) blood pressure and heart rate responses to Valsalva maneuvers were altered. Autonomic changes persisted for several days after landing. These results provide further evidence of functionally relevent reductions in parasympathetic and increases in sympathetic influences on arterial pressure control after spaceflight.

Postural Regulation of Muscle Sympathetic Nerve Activity Before and After Simulated and Actual Microgravity Deconditioning

NASA Technical Reports Server (NTRS)

Pawelczyk, J. A.; Levine, B. D.

1999-01-01

The etiology of orthostatic intolerance after spaceflight is multifaceted. Morphological adaptations, in particular cardiac atrophy, are likely to magnify the decrease in stroke volume that occurs with reductions in cardiac filling pressure when standing. Neural adaptations may be inferred as well, as reductions in carotid-cardiac baroreflex responsiveness have been reported following bedrest deconditioning and spaceflight. Neural control of vascular resistance has not been studied directly when orthostatic intolerance is florid in the hours following spaceflight. However, the increases in systemic vascular resistance and plasma catecholamines during orthostatic stress are inappropriately low in orthostatically intolerant subjects following spaceflight, suggesting that deficits in the regulation of vascular resistance may be associated with hypoadrenergic function. The studies described in this abstract were designed to test this hypothesis.

Aging and the Pathogenic Response to Burn

PubMed Central

Rani, Meenakshi; Schwacha, Martin G.

2012-01-01

Aging is an important and critical factor that contributes to the clinical outcome of burn patients. The very young and the elderly are more likely to succumb after major burn as compared to their adult counterparts. With the aging population, improved understanding of the mechanisms underlying age-associated complications after burns becomes even more demanding. It is widely accepted that elderly burn patients have significantly increased morbidity and mortality. Irrespective of the type of burn injury, the aged population shows slower recoveries and suffers more complications. Age-associated immune dysfunction, immunosenescence, may predispose the elderly burn patients to more infections, slower healing and/or to other complications. Furthermore, pre-existing, age-related medical conditions such as, pulmonary/cardiovascular dysfunctions and diabetes in the elderly are other important factors that contribute to their poorer outcomes after major burn. The present review describes the impact of aging on burn patients outcomes. PMID:22724078

Hypocretin-1 CSF levels in anti-Ma2 associated encephalitis

PubMed Central

Overeem, S.; Dalmau, J.; Bataller, L.; Nishino, S.; Mignot, E.; Verschuuren, J.; Lammers, G.J.

2008-01-01

Idiopathic narcolepsy is associated with deficient hypocretin transmission. Narcoleptic symptoms have recently been described in paraneoplastic encephalitis with anti-Ma2 antibodies. The authors measured CSF hypocretin-1 levels in six patients with anti-Ma2 encephalitis, and screened for anti-Ma antibodies in patients with ideopathic narcolepsy. Anti-Ma autoantibodies were not detected in patients with idiopathic narcolepsy. Four patients with anti-Ma2 encephalitis had excessive daytime sleepiness; hypocretin-1 was not detectable in their cerebrospinal fluid, suggesting an immune-mediated hypocretin dysfunction. PMID:14718718

Insensitivity of Astrocytes to Interleukin-10 Signaling following Peripheral Immune Challenge Results in Prolonged Microglial Activation in the Aged Brain

PubMed Central

Norden, Diana M.; Trojanowski, Paige J.; Walker, Frederick R.; Godbout, Jonathan P.

2017-01-01

Immune-activated microglia from aged mice produce exaggerated levels of cytokines. Despite high levels of microglial IL-10 in the aged brain, neuroinflammation was prolonged and associated with depressive-like deficits. Because astrocytes respond to IL-10 and, in turn, attenuate microglial activation, we investigated if astrocyte-mediated resolution of microglial activation was impaired with age. Here, aged astrocytes had a dysfunctional profile with higher GFAP, lower glutamate transporter expression, and significant cytoskeletal re-arrangement. Moreover, aged astrocytes had reduced expression of growth factors and IL-10 Receptor-1 (IL-10R1). Following in vivo LPS immune challenge, aged astrocytes had a molecular signature associated with reduced responsiveness to IL-10. This IL-10 insensitivity of aged astrocytes resulted in a failure to induce IL-10R1 and TGFβ and resolve microglial activation. Additionally, adult astrocytes reduced microglial activation when co-cultured ex vivo, while aged astrocytes did not. Consistent with the aging studies, IL-10RKO astrocytes did not augment TGFβ after immune challenge and failed to resolve microglial activation. Collectively, a major cytokine-regulatory loop between activated microglia and astrocytes is impaired in the aged brain. PMID:27318131

Immunologic alterations and the pathogenesis of organ failure in the ICU.

PubMed

Opal, Steven M

2011-10-01

Rapid and marked alterations of innate and adaptive immunity typify the host response to systemic infection and acute inflammatory states. Immune dysfunction contributes to the development of organ failure in most patients with critical illness. The molecular mechanisms by which microbial pathogens and tissue injury activate myeloid cells and prime cellular and humoral immunity are increasingly understood. An early and effective immune response to microbial invasion is essential to mount an effective antimicrobial response. However, unchecked and nonresolving inflammation can induce diffuse vasodilation, increased capillary permeability, microvascular damage, coagulation activation, and organ dysfunction. Control of the inflammatory response to limit tissue damage, yet retain the antimicrobial responses in critically ill patients with severe infection, has been sought for decades. Anti-inflammatory approaches might be beneficial in some patients but detrimental in others. It is now clear that a state of sepsis-induced immune suppression can follow the immune activation phase of sepsis. In carefully selected patients, a better therapeutic strategy might be to provide immunoadjuvants to reconstitute immune function in intensive care unit (ICU) patients. Proresolving agents are also in development to terminate acute inflammatory reactions without immune suppression. This brief review summarizes the current understanding of the fundamental immune alterations in critical illness that lead to organ failure in critical illness. © Thieme Medical Publishers.

The Association Between Post-traumatic Stress Disorder and Markers of Inflammation and Immune Activation in HIV-Infected Individuals With Controlled Viremia.

PubMed

Siyahhan Julnes, Peter; Auh, Sungyoung; Krakora, Rebecca; Withers, Keenan; Nora, Diana; Matthews, Lindsay; Steinbach, Sally; Snow, Joseph; Smith, Bryan; Nath, Avindra; Morse, Caryn; Kapetanovic, Suad

2016-01-01

Post-traumatic stress disorder (PTSD) may be associated with chronic immune dysregulation and a proinflammatory state. Among HIV-infected individuals, PTSD is associated with greater morbidity and mortality, but the association with immune dysfunction has not been evaluated. This study explores the association between PTSD and selected markers of inflammation and immune activation in a cohort of HIV-infected, virally-suppressed individuals. HIV-infected adults who were virologically controlled on antiretroviral medications were recruited through a screening protocol for studies of HIV-related neurocognitive disorders. Each participant underwent blood draws, urine toxicology screen, and completed the Client Diagnostic Questionnaire, a semistructured psychiatric interview. Of 114 eligible volunteers, 72 (63%) were male, 77 (68%) African American, and 34 (30%) participants met criteria for PTSD. Participants with PTSD were more likely to be current smokers (79%) than those without (60%) (p = 0.05). The PTSD cohort had significantly higher total white blood cell counts (5318 and 6404 cells/uL, p = 0.03), absolute neutrophil count (2767 and 3577 cells/uL, p = 0.02), CD8% (43 and 48, p = 0.05), and memory CD8% (70 and 78%, p = 0.04); lower naïve CD8% (30 and 22%, p = 0.04) and higher rate of high-sensitivity C-reactive protein >3mg/L (29 and 20, p = 0.03). A high prevalence of PTSD was identified in this cohort of HIV-infected adults who were virally suppressed. These results suggest that PTSD may be associated with immune dysregulation even among antiretroviral therapy-adherent HIV-infected individuals. Published by Elsevier Inc.

The Association between Post-Traumatic Stress Disorder and Markers of Inflammation and Immune Activation in HIV-Infected individuals with Controlled Viremia

PubMed Central

Siyahhan Julnes, Peter; Auh, Sungyoung; Krakora, Rebecca; Withers, Keenan; Nora, Diana; Matthews, Lindsay; Steinbach, Sally; Snow, Joseph; Smith, Bryan; Nath, Avindra; Morse, Caryn; Kapetanovic, Suad

2016-01-01

Introduction Post-traumatic stress disorder (PTSD) may be associated with chronic immune dysregulation and a pro-inflammatory state. Among HIV-infected individuals, PTSD is associated with greater morbidity and mortality, but the association with immune dysfunction has not been evaluated. This study explores the association between PTSD and selected markers of inflammation and immune activation in a cohort of HIV-infected, virally-suppressed individuals. Methods HIV-infected adults who were virologically controlled on anti-retroviral medications were recruited through a screening protocol for studies of HIV-related neurocognitive disorders. Each participant underwent blood draws, urine toxicology screen, and completed the Client Diagnostic Questionnaire (CDQ), a semi-structured psychiatric interview. Results Of 114 eligible volunteers; 72 (63%) were male, 77 (68%) African American, and 34 (30%) participants met criteria for PTSD. Participants with PTSD were more likely to be current smokers (79%) than those without (60%) (p=0.05). The PTSD cohort had significantly higher total white blood cell counts (5318 and 6404 cells/uL, p=0.03), absolute neutrophil count (2767 and 3577 cells/uL, p=0.02), CD8% (43 and 48, p=0.05) and memory CD8% (70 and 78%, p=0.04); lower naïve CD8% (30 and 22%, p=0.04), and higher rate of high-sensitivity C-reactive protein >3 mg/L (29 and 20, p=0.03). Discussion A high prevalence of PTSD was identified in this cohort of HIV-infected adults who were virally-suppressed. These results suggest that PTSD may be associated with immune dysregulation even among ART-adherent HIV-infected individuals. PMID:27095586

Spaceflight-induced Bone Loss: Countermeasures and Their Evaluations

NASA Technical Reports Server (NTRS)

Sibonga, Jean D.

2008-01-01

The learning objectives of this viewgraph presentation are to: (1) Understand the biomedical effects of spaceflight and their associated health risks. (2) Understand how the "Factor of Risk" for fracture can be calculated in the adult skeleton for space travel. and (3) Understand how various countermeasures [CMs] influence the Factor of Risk.

Herpes zoster-associated voiding dysfunction in hematopoietic malignancy patients.

PubMed

Imafuku, Shinichi; Takahara, Masakazu; Uenotsuchi, Takeshi; Iwato, Koji; Furue, Masutaka

2008-01-01

Voiding dysfunction is a rare but important complication of lumbo-sacral herpes zoster. Although the symptoms are transient, the clinical impact on immunocompromised patients cannot be overlooked. To clarify the time course of voiding dysfunction in herpes zoster, 13 herpes zoster patients with voiding dysfunction were retrospectively analyzed. Of 13 patients, 12 had background disease, and six of these were hematopoietic malignancies; four of these patients were hematopoietic stem cell transplant (HSCT) recipients. Ten patients had sacral lesions, two had lumbar, and one had thoracic lesions. Interestingly, patients with severe rash, or with hematopoietic malignancy had later onset of urinary retention than did patients with mild skin symptoms (Mann-Whitney U analysis, P = 0.053) or with other background disease (P = 0.0082). Patients with severe skin rash also had longer durations (P = 0.035). In one case, acute urinary retention occurred as late as 19 days after the onset of skin rash. In immune compromised subjects, attention should be paid to patients with herpes zoster in the lumbo-sacral area for late onset of acute urinary retention even after the resolution of skin symptoms.

Microbiological Lessons Learned from the Space Shuttle

NASA Technical Reports Server (NTRS)

Pierson, Duane L.; Ott, C. Mark; Bruce, Rebekah; Castro, Victoria A.; Mehta, Satish K.

2011-01-01

After 30 years of being the centerpiece of NASA s human spacecraft, the Space Shuttle will retire. This highly successful program provided many valuable lessons for the International Space Station (ISS) and future spacecraft. Major microbiological risks to crewmembers include food, water, air, surfaces, payloads, animals, other crewmembers, and ground support personnel. Adverse effects of microorganisms are varied and can jeopardize crew health and safety, spacecraft systems, and mission objectives. Engineering practices and operational procedures can minimize the negative effects of microorganisms. To minimize problems associated with microorganisms, appropriate steps must begin in the design phase of new spacecraft or space habitats. Spacecraft design must include requirements to control accumulation of water including humidity, leaks, and condensate on surfaces. Materials used in habitable volumes must not contribute to microbial growth. Use of appropriate materials and the implementation of robust housekeeping that utilizes periodic cleaning and disinfection will prevent high levels of microbial growth on surfaces. Air filtration can ensure low levels of bioaerosols and particulates in the breathing air. The use of physical and chemical steps to disinfect drinking water coupled with filtration can provide safe drinking water. Thorough preflight examination of flight crews, consumables, and the environment can greatly reduce pathogens in spacecraft. The advances in knowledge of living and working onboard the Space Shuttle formed the foundation for environmental microbiology requirements and operations for the International Space Station (ISS) and future spacecraft. Research conducted during the Space Shuttle Program resulted in an improved understanding of the effects of spaceflight on human physiology, microbial properties, and specifically the host-microbe interactions. Host-microbe interactions are substantially affected by spaceflight. Astronaut immune functions were found to be altered. Selected microorganisms were found to become more virulent during spaceflight. The increased knowledge gained on the Space Shuttle resulted in further studies of the host-microbe interactions on the ISS to determine if countermeasures were necessary. Lessons learned from the Space Shuttle Program were integrated into the ISS resulting in the safest space habitat to date.

Cardiovascular Adaptations to Long Duration Head-Down Tilt Bed Rest

NASA Technical Reports Server (NTRS)

Platts, Steven H.; Martin, David S.; Perez, Sondar A.; Ribeiro, Christine; Stenger, Michael B.; Summers, Richard; Meck, Janice V.

2008-01-01

INTRODUCTION: Orthostatic hypotension is a serious risk for crewmembers returning from spaceflight. Numerous cardiovascular mechanisms have been proposed to account for this problem, including vascular and cardiac dysfunction, which we studied during bed rest. METHODS: Thirteen subjects were studied before and during bed rest. Statistical analysis was limited to the first 49-60 days of bed rest, and compared to pre-bed rest data. Ultrasound data were collected on vascular and cardiac structure and function. Tilt testing was conducted for 30 minutes or until presyncopal symptoms intervened. RESULTS: Plasma volume was significantly reduced by day 7 of bed rest. Flow-mediated dilation in the leg was significantly increased at bed rest day 49. Arterial responses to nitroglycerin differed in the arm and leg, but did not change as a result of bed rest. Intimal-medial thickness markedly decreased at bed rest days 21, 35 and 49. Several cardiac functional parameters including isovolumic relaxation time, ejection time and myocardial performance index were significantly increased (indicating a decrease in cardiac function) during bed rest. There was a trend for decreased orthostatic tolerance following 60 days of bed rest. DISCUSSION: These data suggest that 6 head-down tilt bed rest alters cardiovascular structure and function in a pattern similar to short duration spaceflight. Additionally, the vascular alterations are primarily seen in the lower body, while vessels of the upper body are unaffected. KEY WORDS: spaceflight, orthostatic intolerance, hypotension, fluid-shift, plasma volume

Latent Virus Reactivation: From Space to Earth

NASA Technical Reports Server (NTRS)

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

2010-01-01

Reactivation of latent viruses is a recognized consequence of decreased immunity. More recently viral reactivation has been identified as an important in vivo indicator of clinically relevant immune changes. Viral reactivation can be determined quickly and easily by the presence of virus in saliva and other body fluids. Real-time polymerase chain reaction (PCR) is a highly sensitive and specific molecular method to detect the presence of specific viral DNA. Studies in astronauts demonstrated that herpes simplex virus type 1(HSV-1), Epstein-Barr Virus (EBV), cytomegalovirus (CMV), and varicella zoster virus (VZV) reactivate at rates above normal during and after spaceflight in response to moderately decreased T-cell immunity. This technology was expanded to patients on Earth beginning with human immune deficiency virus (HIV) immuno-compromised patients. The HIV patients shed EBV in saliva at rates 9-fold higher than observed in astronauts demonstrating that the level of EBV shedding reflects the severity of impaired immunity. Whereas EBV reactivation is not expected to produce serious effects in astronauts on missions of 6 months or less, VZV reactivation in astronauts could produce shingles. Reactivation of live, infectious VZV in astronauts with no symptoms was demonstrated in astronauts during and after spaceflight. We applied our technology to study VZV-induced shingles in patients. In a study of 54 shingles patients, we showed salivary VZV was present in every patient on the day antiviral (acyclovir) treatment was initiated. Pain and skin lesions decreased with antiviral treatment. Corresponding decreases in levels of VZV were also observed and accompanied recovery. Although the level of VZV in shingles patients before the treatment was generally higher than those found in astronauts, lower range of VZV numbers in shingles patients overlapped with astronaut s levels. This suggests a potential risk of shingles to astronauts resulting from reactivation of VZV. In another clinical study of 25 shingles patients, PCR technology detected VZV in the serum and peripheral blood mononuclear cells of all 25 patients demonstrating for the first time that viremia is a common manifestation of herpes shingles.

Updating the mild encephalitis hypothesis of schizophrenia.

PubMed

Bechter, K

2013-04-05

Schizophrenia seems to be a heterogeneous disorder. Emerging evidence indicates that low level neuroinflammation (LLNI) may not occur infrequently. Many infectious agents with low overall pathogenicity are risk factors for psychoses including schizophrenia and for autoimmune disorders. According to the mild encephalitis (ME) hypothesis, LLNI represents the core pathogenetic mechanism in a schizophrenia subgroup that has syndromal overlap with other psychiatric disorders. ME may be triggered by infections, autoimmunity, toxicity, or trauma. A 'late hit' and gene-environment interaction are required to explain major findings about schizophrenia, and both aspects would be consistent with the ME hypothesis. Schizophrenia risk genes stay rather constant within populations despite a resulting low number of progeny; this may result from advantages associated with risk genes, e.g., an improved immune response, which may act protectively within changing environments, although they are associated with the disadvantage of increased susceptibility to psychotic disorders. Specific schizophrenic symptoms may arise with instances of LLNI when certain brain functional systems are involved, in addition to being shaped by pre-existing liability factors. Prodrome phase and the transition to a diseased status may be related to LLNI processes emerging and varying over time. The variability in the course of schizophrenia resembles the varying courses of autoimmune disorders, which result from three required factors: genes, the environment, and the immune system. Preliminary criteria for subgrouping neurodevelopmental, genetic, ME, and other types of schizophrenias are provided. A rare example of ME schizophrenia may be observed in Borna disease virus infection. Neurodevelopmental schizophrenia due to early infections has been estimated by others to explain approximately 30% of cases, but the underlying pathomechanisms of transition to disease remain in question. LLNI (e.g. from reactivation related to persistent infection) may be involved and other pathomechanisms including dysfunction of the blood-brain barrier or the blood-CSF barrier, CNS-endogenous immunity and the volume transmission mode balancing wiring transmission (the latter represented mainly by synaptic transmission, which is often described as being disturbed in schizophrenia). Volume transmission is linked to CSF signaling; and together could represent a common pathogenetic link for the distributed brain dysfunction, dysconnectivity, and brain structural abnormalities observed in schizophrenia. In addition, CSF signaling may extend into peripheral tissues via the CSF outflow pathway along brain nerves and peripheral nerves, and it may explain the peripheral topology of neuronal dysfunctions found, like in olfactory dysfunction, dysautonomia, and even in peripheral tissues, i.e., the muscle lesions that were found in 50% of cases. Modulating factors in schizophrenia, such as stress, hormones, and diet, are also modulating factors in the immune response. Considering recent investigations of CSF, the ME schizophrenia subgroup may constitute approximately 40% of cases. Copyright © 2012 Elsevier Inc. All rights reserved.

Spaceflight has compartment- and gene-specific effects on mRNA levels for bone matrix proteins in rat femur

NASA Technical Reports Server (NTRS)

Evans, G. L.; Morey-Holton, E.; Turner, R. T.

1998-01-01

In the present study, we evaluated the possibility that the abnormal bone matrix produced during spaceflight may be associated with reduced expression of bone matrix protein genes. To test this possibility, we investigated the effects of a 14-day spaceflight (SLS-2 experiment) on steady-state mRNA levels for glyceraldehyde-3-phosphate dehydrogenase (GAPDH), osteocalcin, osteonectin, and prepro-alpha(1) subunit of type I collagen in the major bone compartments of rat femur. There were pronounced site-specific differences in the steady-state levels of expression of the mRNAs for the three bone matrix proteins and GAPDH in normal weight-bearing rats, and these relationships were altered after spaceflight. Specifically, spaceflight resulted in decreases in mRNA levels for GAPDH (decreased in proximal metaphysis), osteocalcin (decreased in proximal metaphysis), osteonectin (decreased in proximal and distal metaphysis), and collagen (decreased in proximal and distal metaphysis) compared with ground controls. There were no changes in mRNA levels for matrix proteins or GAPDH in the shaft and distal epiphysis. These results demonstrate that spaceflight leads to site- and gene-specific decreases in mRNA levels for bone matrix proteins. These findings are consistent with the hypothesis that spaceflight-induced decreases in bone formation are caused by concomitant decreases in expression of genes for bone matrix proteins.

Nutritional status changes in humans during a 14-day saturation dive: the NASA Extreme Environment Mission Operations V project

NASA Technical Reports Server (NTRS)

Smith, Scott M.; Davis-Street, Janis E.; Fesperman, J. Vernell; Smith, Myra D.; Rice, Barbara L.; Zwart, Sara R.

2004-01-01

Ground-based analogs of spaceflight are an important means of studying physiologic and nutritional changes associated with space travel, and the NASA Extreme Environment Mission Operations V (NEEMO) is such an analog. To determine whether saturation diving has nutrition-related effects similar to those of spaceflight, we conducted a clinical nutritional assessment of the NEEMO crew (4 men, 2 women) before, during, and after their 14-d saturation dive. Blood and urine samples were collected before, during, and after the dive. The foods consumed by the crew were typical of the spaceflight food system. A number of physiologic changes were observed, during and after the dive, that are also commonly observed during spaceflight. Hemoglobin and hematocrit were lower (P < 0.05) after the dive. Transferrin receptors were significantly lower immediately after the dive. Serum ferritin increased significantly during the dive. There was also evidence indicating that oxidative damage and stress increased during the dive. Glutathione peroxidase and superoxide dismutase decreased during and after the dive (P < 0.05). Decreased leptin during the dive (P < 0.05) may have been related to the increased stress. Subjects had decreased energy intake and weight loss during the dive, similar to what is observed during spaceflight. Together, these similarities to spaceflight provide a model to use in further defining the physiologic effects of spaceflight and investigating potential countermeasures.

One-month spaceflight compromises the bone microstructure, tissue-level mechanical properties, osteocyte survival and lacunae volume in mature mice skeletons.

PubMed

Gerbaix, Maude; Gnyubkin, Vasily; Farlay, Delphine; Olivier, Cécile; Ammann, Patrick; Courbon, Guillaume; Laroche, Norbert; Genthial, Rachel; Follet, Hélène; Peyrin, Françoise; Shenkman, Boris; Gauquelin-Koch, Guillemette; Vico, Laurence

2017-06-01

The weightless environment during spaceflight induces site-specific bone loss. The 30-day Bion-M1 mission offered a unique opportunity to characterize the skeletal changes after spaceflight and an 8-day recovery period in mature male C57/BL6 mice. In the femur metaphysis, spaceflight decreased the trabecular bone volume (-64% vs. Habitat Control), dramatically increased the bone resorption (+140% vs. Habitat Control) and induced marrow adiposity invasion. At the diaphysis, cortical thinning associated with periosteal resorption was observed. In the Flight animal group, the osteocyte lacunae displayed a reduced volume and a more spherical shape (synchrotron radiation analyses), and empty lacunae were highly increased (+344% vs. Habitat Control). Tissue-level mechanical cortical properties (i.e., hardness and modulus) were locally decreased by spaceflight, whereas the mineral characteristics and collagen maturity were unaffected. In the vertebrae, spaceflight decreased the overall bone volume and altered the modulus in the periphery of the trabecular struts. Despite normalized osteoclastic activity and an increased osteoblast number, bone recovery was not observed 8 days after landing. In conclusion, spaceflight induces osteocyte death, which may trigger bone resorption and result in bone mass and microstructural deterioration. Moreover, osteocyte cell death, lacunae mineralization and fatty marrow, which are hallmarks of ageing, may impede tissue maintenance and repair.

Spaceflight Enhances Cell Aggregation and Random Budding in Candida albicans

PubMed Central

Woolley, Christine M.; Barrila, Jennifer; Buchanan, Kent; McCracken, James; Inglis, Diane O.; Searles, Stephen C.; Nelman-Gonzalez, Mayra A.; Ott, C. Mark; Wilson, James W.; Pierson, Duane L.; Stefanyshyn-Piper, Heidemarie M.; Hyman, Linda E.; Nickerson, Cheryl A.

2013-01-01

This study presents the first global transcriptional profiling and phenotypic characterization of the major human opportunistic fungal pathogen, Candida albicans, grown in spaceflight conditions. Microarray analysis revealed that C. albicans subjected to short-term spaceflight culture differentially regulated 452 genes compared to synchronous ground controls, which represented 8.3% of the analyzed ORFs. Spaceflight-cultured C. albicans–induced genes involved in cell aggregation (similar to flocculation), which was validated by microscopic and flow cytometry analysis. We also observed enhanced random budding of spaceflight-cultured cells as opposed to bipolar budding patterns for ground samples, in accordance with the gene expression data. Furthermore, genes involved in antifungal agent and stress resistance were differentially regulated in spaceflight, including induction of ABC transporters and members of the major facilitator family, downregulation of ergosterol-encoding genes, and upregulation of genes involved in oxidative stress resistance. Finally, downregulation of genes involved in actin cytoskeleton was observed. Interestingly, the transcriptional regulator Cap1 and over 30% of the Cap1 regulon was differentially expressed in spaceflight-cultured C. albicans. A potential role for Cap1 in the spaceflight response of C. albicans is suggested, as this regulator is involved in random budding, cell aggregation, and oxidative stress resistance; all related to observed spaceflight-associated changes of C. albicans. While culture of C. albicans in microgravity potentiates a global change in gene expression that could induce a virulence-related phenotype, no increased virulence in a murine intraperitoneal (i.p.) infection model was observed under the conditions of this study. Collectively, our data represent an important basis for the assessment of the risk that commensal flora could play during human spaceflight missions. Furthermore, since the low fluid-shear environment of microgravity is relevant to physical forces encountered by pathogens during the infection process, insights gained from this study could identify novel infectious disease mechanisms, with downstream benefits for the general public. PMID:24324620

The pituitary - Aging and spaceflown rats

NASA Technical Reports Server (NTRS)

Hymer, W. C.; Grindeland, R. E.

1991-01-01

Decrements in growth hormone (GH) release we observed in two spaceflight experiments and four tail-suspended rat studies mimic age-associated changes in the mammalian pituitary GH system seen by Meites and others. The spaceflight data suggest that formation of high molecular weight bioactive disulfide-linked aggregates of the 20 and 22K monomeric GH forms may be reduced in microgravity, thereby, reducing target tissue activity. Correlative studies to confirm spaceflight as a model for pituitary GH system aging should include: (1) investigation of mechanisms of intracellular hormone packaging, (2) consequences to biological activity of the hormone molecule, and (3) study of intracellular microtubule dynamics.

Interferon-alpha, immune activation and immune dysfunction in treated HIV infection

PubMed Central

Cha, Lilian; Berry, Cassandra M; Nolan, David; Castley, Allison; Fernandez, Sonia; French, Martyn A

2014-01-01

Type I interferons (IFNs) exert anti-viral effects through the induction of numerous IFN-stimulated genes and an immunomodulatory effect on innate and adaptive immune responses. This is beneficial in controlling virus infections but prolonged IFN-α activity in persistent virus infections, such as HIV infection, may contribute to immune activation and have a detrimental effect on the function of monocytes and T and B lymphocytes. Activation of monocytes, associated with increased IFN-α activity, contributes to atherosclerotic vascular disease, brain disease and other ‘age-related diseases' in HIV patients treated with long-term antiretroviral therapy (ART). In HIV patients receiving ART, the anti-viral effects of IFN-α therapy have the potential to contribute to eradication of HIV infection while IFN-α inhibitor therapy is under investigation for the treatment of immune activation. The management of HIV patients receiving ART will be improved by understanding more about the opposing effects of IFN-α on HIV infection and disease and by developing methods to assess IFN-α activity in clinical practice. PMID:25505958

Astrocyte atrophy and immune dysfunction in self-harming macaques.

PubMed

Lee, Kim M; Chiu, Kevin B; Sansing, Hope A; Inglis, Fiona M; Baker, Kate C; MacLean, Andrew G

2013-01-01

Self-injurious behavior (SIB) is a complex condition that exhibits a spectrum of abnormal neuropsychological and locomotor behaviors. Mechanisms for neuropathogenesis could include irregular immune activation, host soluble factors, and astrocyte dysfunction. We examined the role of astrocytes as modulators of immune function in macaques with SIB. We measured changes in astrocyte morphology and function. Paraffin sections of frontal cortices from rhesus macaques identified with SIB were stained for glial fibrillary acidic protein (GFAP) and Toll-like receptor 2 (TLR2). Morphologic features of astrocytes were determined using computer-assisted camera lucida. There was atrophy of white matter astrocyte cell bodies, decreased arbor length in both white and gray matter astrocytes, and decreased bifurcations and tips on astrocytes in animals with SIB. This was combined with a five-fold increase in the proportion of astrocytes immunopositive for TLR2. These results provide direct evidence that SIB induces immune activation of astrocytes concomitant with quantifiably different morphology.

CXCR3 ligands are associated with the continuum of diffuse alveolar damage to chronic lung allograft dysfunction.

PubMed

Shino, Michael Y; Weigt, S Samuel; Li, Ning; Palchevskiy, Vyacheslav; Derhovanessian, Ariss; Saggar, Rajan; Sayah, David M; Gregson, Aric L; Fishbein, Michael C; Ardehali, Abbas; Ross, David J; Lynch, Joseph P; Elashoff, Robert M; Belperio, John A

2013-11-01

After lung transplantation, insults to the allograft generally result in one of four histopathologic patterns of injury: (1) acute rejection, (2) lymphocytic bronchiolitis, (3) organizing pneumonia, and (4) diffuse alveolar damage (DAD). We hypothesized that DAD, the most severe form of acute lung injury, would lead to the highest risk of chronic lung allograft dysfunction (CLAD) and that a type I immune response would mediate this process. Determine whether DAD is associated with CLAD and explore the potential role of CXCR3/ligand biology. Transbronchial biopsies from all lung transplant recipients were reviewed. The association between the four injury patterns and subsequent outcomes were evaluated using proportional hazards models with time-dependent covariates. Bronchoalveolar lavage (BAL) concentrations of the CXCR3 ligands (CXCL9/MIG, CXCL10/IP10, and CXCL11/ITAC) were compared between allograft injury patterns and "healthy" biopsies using linear mixed-effects models. The effect of these chemokine alterations on CLAD risk was assessed using Cox models with serial BAL measurements as time-dependent covariates. There were 1,585 biopsies from 441 recipients with 62 episodes of DAD. An episode of DAD was associated with increased risk of CLAD (hazard ratio, 3.0; 95% confidence interval, 1.9-4.7) and death (hazard ratio, 2.3; 95% confidence interval, 1.7-3.0). There were marked elevations in BAL CXCR3 ligand concentrations during DAD. Furthermore, prolonged elevation of these chemokines in serial BAL fluid measurements predicted the development of CLAD. DAD is associated with marked increases in the risk of CLAD and death after lung transplantation. This association may be mediated in part by an aberrant type I immune response involving CXCR3/ligands.

Microglia, the missing link in maternal immune activation and fetal neurodevelopment; and a possible link in preeclampsia and disturbed neurodevelopment?

PubMed

Prins, Jelmer R; Eskandar, Sharon; Eggen, Bart J L; Scherjon, Sicco A

2018-04-01

Disturbances in fetal neurodevelopment have extensively been related to neurodevelopmental disorders in early and later life. Fetal neurodevelopment is dependent on adequate functioning of the fetal immune system. During pregnancy, the maternal immune system is challenged to both tolerate the semi-allogenic fetus and to protect the mother and fetus from microbes. The fetal immune system is influenced by maternal immune disturbances; therefore, perturbations in maternal immunity likely do not only alter pregnancy outcome but also alter fetal neurodevelopment. A possible common pathway could be modulating the functioning of tissue macrophages in the placenta and brain. Maternal immune tolerance towards the fetus involves several complex adaptations. In this active maternal immune state, the fetus develops its own immunity. As cytokines and other players of the immune system -which can pass the placenta- are involved in neurodevelopment, disruptions in immune balance influence fetal neurodevelopment. Several studies reported an association between maternal immune activation, complications of pregnancy as preeclampsia, and altered neonatal neurodevelopment. A possible pathway involves dysfunctioning of microglia cells, the immune cells of the brain. Functionality of microglia cells during normal pregnancy is, however, poorly understood. The recent outbreak of ZIKA virus (ZKV), but also the literature on virus infections in general and its consequences on microglial cell function and fetal neurodevelopment show the devastating effects a virus infection during pregnancy can have. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Immunity, ageing and cancer

PubMed Central

Derhovanessian, Evelyna; Solana, Rafael; Larbi, Anis; Pawelec, Graham

2008-01-01

Compromised immunity contributes to the decreased ability of the elderly to control infectious disease and to their generally poor response to vaccination. It is controversial as to how far this phenomenon contributes to the well-known age-associated increase in the occurrence of many cancers in the elderly. However, should the immune system be important in controlling cancer, for which there is a great deal of evidence, it is logical to propose that dysfunctional immunity in the elderly would contribute to compromised immunosurveillance and increased cancer occurrence. The chronological age at which immunosenescence becomes clinically important is known to be influenced by many factors, including the pathogen load to which individuals are exposed throughout life. It is proposed here that the cancer antigen load may have a similar effect on "immune exhaustion" and that pathogen load and tumor load may act additively to accelerate immunosenescence. Understanding how and why immune responsiveness changes in humans as they age is essential for developing strategies to prevent or restore dysregulated immunity and assure healthy longevity, clearly possible only if cancer is avoided. Here, we provide an overview of the impact of age on human immune competence, emphasizing T-cell-dependent adaptive immunity, which is the most sensitive to ageing. This knowledge will pave the way for rational interventions to maintain or restore appropriate immune function not only in the elderly but also in the cancer patient. PMID:18816370

[Researches in immunological responses after burn injury in China].

PubMed

Peng, Dai-zhi

2008-10-01

For five decades it has been recognized that severe burn injury may precipitate in marked alterations in immune function, resulting in life-threatening systemic infections, sepsis, multiple organ failure, and even death. Extensive and deep burns exert widespread and profound impacts on various cells and molecules of the immune system. The general characteristics of abnormal immune responses following major burns are hyperinflammatory response and hypoimmune response of innate and adaptive immunity. These are recognized as postburn immune dysfunction (PID). The stress reaction, massive necrotic tissue, shock, infection, malnutrition and various therapeutic procedures after burns alter the microenvironment of the immune cells and molecules in which they reside, and consequently result in the changes in immune cells and their secretions in quantity and/or activity, and also aberrant signal transduction in different immune cells. These events constitute the cellular and molecular bases in the pathogenesis of PID. The main clinical consequences of PID include tissue damages and increased susceptibility to opportunistic pathogens caused by refractory inflammation and suppressed adaptive immunity. In order to decrease the morbidity of these lethal complications, efforts to improve the immune dysfunction after burn injury have been made not only at the integral level of etiological factors, but also at the cellular and molecular levels of its mechanisms. In this review, all these above-mentioned aspects of PID are comprehensively discussed.

Mechanisms of PD-L1/PD-1-mediated CD8 T-cell dysfunction in the context of aging-related immune defects in the Eµ-TCL1 CLL mouse model.

PubMed

McClanahan, Fabienne; Riches, John C; Miller, Shaun; Day, William P; Kotsiou, Eleni; Neuberg, Donna; Croce, Carlo M; Capasso, Melania; Gribben, John G

2015-07-09

T-cell defects, immune suppression, and poor antitumor immune responses are hallmarks of chronic lymphocytic leukemia (CLL), and PD-1/PD-L1 inhibitory signaling has emerged as a major immunosuppressive mechanism. However, the effect of different microenvironments and the confounding influence of aging are poorly understood. The current study uses the Eμ-TCL1 mouse model, which replicates human T-cell defects, as a preclinical platform to longitudinally examine patterns of T-cell dysfunction alongside developing CLL and in different microenvironments, with a focus on PD-1/PD-L1 interactions. The development of CLL was significantly associated with changes in T-cell phenotype across all organs and function. Although partly mirrored in aging wild-type mice, CLL-specific T-cell changes were identified. Murine CLL cells highly expressed PD-L1 and PD-L2 in all organs, with high PD-L1 expression in the spleen. CD3(+)CD8(+) T cells from leukemic and aging healthy mice highly expressed PD-1, identifying aging as a confounder, but adoptive transfer experiments demonstrated CLL-specific PD-1 induction. Direct comparisons of PD-1 expression and function between aging CLL mice and controls identified PD-1(+) T cells in CLL as a heterogeneous population with variable effector function. This is highly relevant for therapeutic targeting of CD8(+) T cells, showing the potential of reprogramming and selective subset expansion to restore antitumor immunity. © 2015 by The American Society of Hematology.

Mechanisms of PD-L1/PD-1–mediated CD8 T-cell dysfunction in the context of aging-related immune defects in the Eµ-TCL1 CLL mouse model

PubMed Central

McClanahan, Fabienne; Riches, John C.; Miller, Shaun; Day, William P.; Kotsiou, Eleni; Neuberg, Donna; Croce, Carlo M.; Capasso, Melania

2015-01-01

T-cell defects, immune suppression, and poor antitumor immune responses are hallmarks of chronic lymphocytic leukemia (CLL), and PD-1/PD-L1 inhibitory signaling has emerged as a major immunosuppressive mechanism. However, the effect of different microenvironments and the confounding influence of aging are poorly understood. The current study uses the Eμ-TCL1 mouse model, which replicates human T-cell defects, as a preclinical platform to longitudinally examine patterns of T-cell dysfunction alongside developing CLL and in different microenvironments, with a focus on PD-1/PD-L1 interactions. The development of CLL was significantly associated with changes in T-cell phenotype across all organs and function. Although partly mirrored in aging wild-type mice, CLL-specific T-cell changes were identified. Murine CLL cells highly expressed PD-L1 and PD-L2 in all organs, with high PD-L1 expression in the spleen. CD3+CD8+ T cells from leukemic and aging healthy mice highly expressed PD-1, identifying aging as a confounder, but adoptive transfer experiments demonstrated CLL-specific PD-1 induction. Direct comparisons of PD-1 expression and function between aging CLL mice and controls identified PD-1+ T cells in CLL as a heterogeneous population with variable effector function. This is highly relevant for therapeutic targeting of CD8+ T cells, showing the potential of reprogramming and selective subset expansion to restore antitumor immunity. PMID:25979947

Protracted immune disorders at one year after ICU discharge in patients with septic shock.

PubMed

Riché, Florence; Chousterman, Benjamin G; Valleur, Patrice; Mebazaa, Alexandre; Launay, Jean-Marie; Gayat, Etienne

2018-02-21

Sepsis is a leading cause of mortality and critical illness worldwide and is associated with an increased mortality rate in the months following hospital discharge. The occurrence of persistent or new organ dysfunction(s) after septic shock raises questions about the mechanisms involved in the post-sepsis status. The present study aimed to explore the immune profiles of patients one year after being discharged from the intensive care unit (ICU) following treatment for abdominal septic shock. We conducted a prospective, single-center, observational study in the surgical ICU of a university hospital. Eighty-six consecutive patients admitted for septic shock of abdominal origin were included in this study. Fifteen different plasma biomarkers were measured at ICU admission, at ICU discharge and at one year after ICU discharge. Three different clusters of biomarkers were distinguished according to their functions, namely: (1) inflammatory response, (2) cell damage and apoptosis, (3) immunosuppression and resolution of inflammation. The primary objective was to characterize variations in the immune status of septic shock patients admitted to ICU up to one year after ICU discharge. The secondary objective was to evaluate the relationship between these biomarker variations and patient outcomes. At the onset of septic shock, we observed a cohesive pro-inflammatory profile and low levels of inflammation resolution markers. At ICU discharge, the immune status demonstrated decreased but persistent inflammation and increased immunosuppression, with elevated programmed cell death protein-1 (PD-1) levels, and a counterbalanced resolution process, with elevated levels of interleukin-10 (IL-10), resolvin D5 (RvD5), and IL-7. One year after hospital discharge, homeostasis was not completely restored with several markers of inflammation remaining elevated. Remarkably, IL-7 was persistently elevated, with levels comparable to those observed after ICU discharge, and PD-1, while lower, remained in the elevated abnormal range. In this study, protracted immune disturbances were observed one year after ICU discharge. The study results suggested the presence of long-lasting immune illness disorders following a long-term septic insult, indicating the need for long-term patient follow up after ICU discharge and questioning the use of immune intervention to restore immune homeostasis after abdominal septic shock.

Spaceflight and the Mouse Eye: Results from Experiments on Shuttle Missions STS-133 and STS-135

NASA Technical Reports Server (NTRS)

Zanello, Susana B.; Theriot, Corey A.; Ponce, Claudia Prospero; Chevez-Barrios, Patricia

2013-01-01

Vision alterations associated with globe flattening, chorodial folds and papilledema, shown in some crew members returning from long duration missions. Hypothesis: Ocular neuroanatomical changes observed in the VIIP syndrome are accompanied by retinal changes at the molecular and cellular level that may affect retinal health and physiology. Objective: Investigate evidence of ocular (retinal) changes associated with spaceflight: (1) histological markers of cellular death and damage (2) molecular markers of oxidative stress (3) gene expression markers of stress

PD-1/PD-L1 Blockade: Have We Found the Key to Unleash the Antitumor Immune Response?

PubMed Central

Xu-Monette, Zijun Y.; Zhang, Mingzhi; Li, Jianyong; Young, Ken H.

2017-01-01

PD-1–PD-L1 interaction is known to drive T cell dysfunction, which can be blocked by anti-PD-1/PD-L1 antibodies. However, studies have also shown that the function of the PD-1–PD-L1 axis is affected by the complex immunologic regulation network, and some CD8+ T cells can enter an irreversible dysfunctional state that cannot be rescued by PD-1/PD-L1 blockade. In most advanced cancers, except Hodgkin lymphoma (which has high PD-L1/L2 expression) and melanoma (which has high tumor mutational burden), the objective response rate with anti-PD-1/PD-L1 monotherapy is only ~20%, and immune-related toxicities and hyperprogression can occur in a small subset of patients during PD-1/PD-L1 blockade therapy. The lack of efficacy in up to 80% of patients was not necessarily associated with negative PD-1 and PD-L1 expression, suggesting that the roles of PD-1/PD-L1 in immune suppression and the mechanisms of action of antibodies remain to be better defined. In addition, important immune regulatory mechanisms within or outside of the PD-1/PD-L1 network need to be discovered and targeted to increase the response rate and to reduce the toxicities of immune checkpoint blockade therapies. This paper reviews the major functional and clinical studies of PD-1/PD-L1, including those with discrepancies in the pathologic and biomarker role of PD-1 and PD-L1 and the effectiveness of PD-1/PD-L1 blockade. The goal is to improve understanding of the efficacy of PD-1/PD-L1 blockade immunotherapy, as well as enhance the development of therapeutic strategies to overcome the resistance mechanisms and unleash the antitumor immune response to combat cancer. PMID:29255458

PD-1/PD-L1 Blockade: Have We Found the Key to Unleash the Antitumor Immune Response?

PubMed

Xu-Monette, Zijun Y; Zhang, Mingzhi; Li, Jianyong; Young, Ken H

2017-01-01

PD-1-PD-L1 interaction is known to drive T cell dysfunction, which can be blocked by anti-PD-1/PD-L1 antibodies. However, studies have also shown that the function of the PD-1-PD-L1 axis is affected by the complex immunologic regulation network, and some CD8 + T cells can enter an irreversible dysfunctional state that cannot be rescued by PD-1/PD-L1 blockade. In most advanced cancers, except Hodgkin lymphoma (which has high PD-L1/L2 expression) and melanoma (which has high tumor mutational burden), the objective response rate with anti-PD-1/PD-L1 monotherapy is only ~20%, and immune-related toxicities and hyperprogression can occur in a small subset of patients during PD-1/PD-L1 blockade therapy. The lack of efficacy in up to 80% of patients was not necessarily associated with negative PD-1 and PD-L1 expression, suggesting that the roles of PD-1/PD-L1 in immune suppression and the mechanisms of action of antibodies remain to be better defined. In addition, important immune regulatory mechanisms within or outside of the PD-1/PD-L1 network need to be discovered and targeted to increase the response rate and to reduce the toxicities of immune checkpoint blockade therapies. This paper reviews the major functional and clinical studies of PD-1/PD-L1, including those with discrepancies in the pathologic and biomarker role of PD-1 and PD-L1 and the effectiveness of PD-1/PD-L1 blockade. The goal is to improve understanding of the efficacy of PD-1/PD-L1 blockade immunotherapy, as well as enhance the development of therapeutic strategies to overcome the resistance mechanisms and unleash the antitumor immune response to combat cancer.

Zinc in Infection and Inflammation

PubMed Central

Gammoh, Nour Zahi; Rink, Lothar

2017-01-01

Micronutrient homeostasis is a key factor in maintaining a healthy immune system. Zinc is an essential micronutrient that is involved in the regulation of the innate and adaptive immune responses. The main cause of zinc deficiency is malnutrition. Zinc deficiency leads to cell-mediated immune dysfunctions among other manifestations. Consequently, such dysfunctions lead to a worse outcome in the response towards bacterial infection and sepsis. For instance, zinc is an essential component of the pathogen-eliminating signal transduction pathways leading to neutrophil extracellular traps (NET) formation, as well as inducing cell-mediated immunity over humoral immunity by regulating specific factors of differentiation. Additionally, zinc deficiency plays a role in inflammation, mainly elevating inflammatory response as well as damage to host tissue. Zinc is involved in the modulation of the proinflammatory response by targeting Nuclear Factor Kappa B (NF-κB), a transcription factor that is the master regulator of proinflammatory responses. It is also involved in controlling oxidative stress and regulating inflammatory cytokines. Zinc plays an intricate function during an immune response and its homeostasis is critical for sustaining proper immune function. This review will summarize the latest findings concerning the role of this micronutrient during the course of infections and inflammatory response and how the immune system modulates zinc depending on different stimuli. PMID:28629136

Zinc in Infection and Inflammation.

PubMed

Gammoh, Nour Zahi; Rink, Lothar

2017-06-17

Micronutrient homeostasis is a key factor in maintaining a healthy immune system. Zinc is an essential micronutrient that is involved in the regulation of the innate and adaptive immune responses. The main cause of zinc deficiency is malnutrition. Zinc deficiency leads to cell-mediated immune dysfunctions among other manifestations. Consequently, such dysfunctions lead to a worse outcome in the response towards bacterial infection and sepsis. For instance, zinc is an essential component of the pathogen-eliminating signal transduction pathways leading to neutrophil extracellular traps (NET) formation, as well as inducing cell-mediated immunity over humoral immunity by regulating specific factors of differentiation. Additionally, zinc deficiency plays a role in inflammation, mainly elevating inflammatory response as well as damage to host tissue. Zinc is involved in the modulation of the proinflammatory response by targeting Nuclear Factor Kappa B (NF-κB), a transcription factor that is the master regulator of proinflammatory responses. It is also involved in controlling oxidative stress and regulating inflammatory cytokines. Zinc plays an intricate function during an immune response and its homeostasis is critical for sustaining proper immune function. This review will summarize the latest findings concerning the role of this micronutrient during the course of infections and inflammatory response and how the immune system modulates zinc depending on different stimuli.

Elevated liver stiffness is linked to increased biomarkers of inflammation and immune activation in HIV/hepatitis C virus-coinfected patients.

PubMed

Medrano, Luz M; Garcia-Broncano, Pilar; Berenguer, Juan; González-García, Juan; Jiménez-Sousa, Ma Ángeles; Guardiola, Josep M; Crespo, Manuel; Quereda, Carmen; Sanz, José; Canorea, Isabel; Carrero, Ana; Hontañón, Victor; Muñoz-Fernández, Ma Ángeles; Resino, Salvador

2018-06-01

Immune dysregulation is a hallmark of HIV and hepatitis C virus (HCV) infections. We aimed to evaluate the relationship between liver stiffness measurement (LSM) and biomarkers of T-cell activation, bacterial translocation, inflammation, endothelial dysfunction, and coagulopathy in HIV/HCV-coinfected patients. Cross-sectional study. We studied 238 HIV/HCV-coinfected patients, 32 healthy controls, and 39 HIV-monoinfected patients. Patients were stratified according to LSM into four groups: less than 12.5, 12.5-25, 25-40, and more than 40 kPa. T-cell subsets were measured using flow cytometry and plasma biomarkers using immunoassays. HIV/HCV-coinfected patients had higher biomarker levels of immune activation in peripheral blood [T-cell activation (CD4CD38 and CD8CD38), bacterial translocation (soluble CD14), inflammation [IL-1b, IL-6, IL-8, IL-18, IFN-γ-inducible protein 10 (IP-10)] endothelial dysfunction [soluble vascular cell adhesion molecule 1 (sVCAM1), soluble intercellular cell adhesion molecule 1 (sICAM1), and soluble tumor necrosis factor receptor 1 (sTNFR1)], and coagulopathy (plasminogen activator inhibitor-1)] than healthy controls and HIV-monoinfected patients. Moreover, in HIV/HCV-coinfected patients, a direct relationship between LSM and immune activation [T-cell activation (CD8CD38 bacterial translocation (lipopolysaccharide), inflammation (IL-8, IP-10), endothelial dysfunction (sVCAM1, sICAM1, and sTNFR1), and coagulopathy (D-dimer)] was found. Subsequently, patients were stratified into different fibrosis stages, finding that patients with cirrhosis who had LSM at least 40 kPa showed higher biomarker values of immune activation [T-cell activation (CD4CD38 and CD8CD38), bacterial translocation (lipopolysaccharide), inflammation (IL-8, IL-6, IP-10), endothelial dysfunction (sVCAM1, sICAM1, and sTNFR1), and coagulopathy (D-dimer)] than patients from the other three groups (<12.5, 12.5-25, and 25-40 kPa). T-cell activation, bacterial translocation, inflammation, endothelial dysfunction, and coagulopathy increased with the severity of liver fibrosis in HIV/HCV-coinfected patients, particularly in patients who had LSM at least 40 kPa.

Incidence of Thyroid-Related Adverse Events in Melanoma Patients Treated With Pembrolizumab

PubMed Central

Jansen, Yanina; Schreuer, Max; Everaert, Hendrik; Velkeniers, Brigitte; Neyns, Bart; Bravenboer, Bert

2016-01-01

Context: Immune checkpoint blockade is associated with endocrine-related adverse events. Thyroid dysfunction during pembrolizumab therapy, an anti-programmed cell death 1 (PD-1) receptor monoclonal antibody, remains to be fully characterized. Objective: To assess the incidence and characteristics of pembrolizumab-associated thyroid dysfunction. Design and Setting: Thyroid function was monitored prospectively in melanoma patients who initiated pembrolizumab within an expanded access program at a referral oncology center. 18Fluorodeoxyglucose uptake on positron emission tomography/computed tomography (18FDG-PET/CT) was reviewed in cases compatible with inflammatory thyroiditis. Patients: Ninety-nine patients with advanced melanoma (age, 26.3–93.6 years; 63.6% females) who received at least one administration of pembrolizumab. Main Outcome Measures: Patient characteristics, thyroid function (TSH, free T4), thyroid autoantibodies, and 18FDG-PET/CT. Results: Eighteen adverse events of thyroid dysfunction were observed in 17 patients. Thyrotoxicosis occurred in 12 patients, of which nine evolved to hypothyroidism. Isolated hypothyroidism was present in six patients. Levothyroxine therapy was required in 10 of 15 hypothyroid patients. Thyroid autoantibodies were elevated during thyroid dysfunction in four of 10 cases. Diffuse increased 18FDG uptake by the thyroid gland was observed in all seven thyrotoxic patients who progressed to hypothyroidism. Conclusions: Thyroid dysfunction is common in melanoma patients treated with pembrolizumab. Hypothyroidism and thyrotoxicosis related to inflammatory thyroiditis are the most frequent presentations. Serial measurements of thyroid function tests are indicated during anti-PD-1 monoclonal antibody therapy. Thyrotoxicosis compatible with inflammatory thyroiditis was associated with diffuse increased 18FDG uptake by the thyroid gland. The prospective role of thyroid autoantibodies should be further investigated, together with the histopathological correlates. PMID:27571185

Immune function biomarker QuantiFERON-monitor is associated with infection risk in cirrhotic patients

PubMed Central

Sood, Siddharth; Yu, Lijia; Visvanathan, Kumar; Angus, Peter William; Gow, Paul John; Testro, Adam Gareth

2016-01-01

AIM To investigate whether a novel immune function biomarker QuantiFERON-Monitor (QFM) can identify cirrhotic patients at greatest risk of infection. METHODS Adult cirrhotic patients on the liver transplant waiting list were recruited for this observational cohort study from a tertiary liver transplant referral unit. The immune function biomarker, QFM was performed using the same method as the widely available Quantiferon-gold assay, and measures output in interferon gamma in IU/mL after dual stimulation of the innate and adaptive immune systems. Ninety-one cirrhotic patients were recruited, with 47 (52%) transplanted on the day of their QFM. The remaining 44 (48%) were monitored for infections until transplant, death, or census date of 1st February 2014. RESULTS Cirrhotic patients express a median QFM significantly lower than healthy controls (94.5 IU/mL vs 423 IU/mL), demonstrating that they are severely immunosuppressed. Several factors including model for end stage liver disease, presence of hepatocellular carcinoma, bilirubin, international normalized ratio and haemoglobin were associated with QFM on univariate analysis. Disease aetiology did not appear to impact QFM. On multivariate analysis, only Child-Pugh score and urea were significantly associated with a patient’s immune function as objectively measured by QFM. In the 44 patients who were not transplanted immediately after their blood test and could be monitored for subsequent infection risk, 13 (29.5%) experienced a pre-transplant infection a median 20 d (range 2-182) post-test. QFM < 214 IU/mL was associated with HR = 4.1 (P = 0.01) for infection. A very low QFM < 30 IU/mL was significantly associated (P = 0.003) with death in three patients who died while awaiting transplantation (HR = 56.6). CONCLUSION QFM is lower in cirrhotics, allowing objective determinations of an individual’s unique level of immune dysfunction. Low QFM was associated with increased susceptibility to infection. PMID:28050238

The Effect of Microgravity on the Smallest Space Travelers: Bacterial Physiology and Virulence on Earth and in Microgravity

NASA Technical Reports Server (NTRS)

Pyle, Barry; Vasques, Marilyn; Aquilina, Rudy (Technical Monitor)

2002-01-01

Since the first human flights outside of Earth's gravity, crew health and well-being have been major concerns. Exposure to microgravity during spaceflight is known to affect the human immune response, possibly making the crew members more vulnerable to infectious disease. In addition, biological experiments previously flown in space have shown that bacteria grow faster in microgravity than they do on Earth. The ability of certain antibiotics to control bacterial infections may also differ greatly in microgravity. It is therefore critical to understand how spaceflight and microgravity affect bacterial virulence, which is their ability to cause disease. By utilizing spaceflight hardware provided by the European Space Agency (ESA), Dr. Barry Pyle and his team at Montana State University, Bozeman, will be performing an experiment to study the effects of microgravity on the virulence of a common soil and water bacterium, Pseudomonas aeruginosa. Importantly, these bacteria have been detected in the water supplies of previous Space Shuttle flights. The experiment will examine the effects of microgravity exposure on bacterial growth and on the bacterium's ability to form a toxin called Exotoxin A. Another goal is to evaluate the effects of microgravity on the physiology of the bacteria by analyzing their ability to respire (produce energy), by studying the condition of the plasma membrane surrounding the cell, and by determining if specific enzymes remain active. Proteins produced by the bacteria will also be assayed to see if the normal functions of the bacteria are affected. In the context of human life support in spaceflight, the results of this experiment will offer guidance in providing the highest possible water quality for the Shuttle in order to limit the risk of infection to human occupants and to minimize water system and spacecraft deterioration.

Nutritional strategies to boost immunity and prevent infection in elderly individuals.

PubMed

High, K P

2001-12-01

Older adults are at risk for malnutrition, which may contribute to their increased risk of infection. Nutritional supplementation strategies can reduce this risk and reverse some of the immune dysfunction associated with advanced age. This review discusses nutritional interventions that have been examined in clinical trials of older adults. The data support use of a daily multivitamin or trace-mineral supplement that includes zinc (elemental zinc, >20 mg/day) and selenium (100 microg/day), with additional vitamin E, to achieve a daily dosage of 200 mg/day. Specific syndromes may also be addressed by nutritional interventions (for example, cranberry juice consumption to reduce urinary tract infections) and may reduce antibiotic use in older adults, particularly those living in long-term care facilities. Drug-nutrient interactions are common in elderly individuals, and care providers should be aware of these interactions. Future research should evaluate important clinical end points rather than merely surrogate markers of immunity.

Applications of the FIV Model to Study HIV Pathogenesis

PubMed Central

Abdo, Zaid; Ericsson, Aaron; Elder, John; VandeWoude, Sue

2018-01-01

Feline immunodeficiency virus (FIV) is a naturally-occurring retrovirus that infects domestic and non-domestic feline species, producing progressive immune depletion that results in an acquired immunodeficiency syndrome (AIDS). Much has been learned about FIV since it was first described in 1987, particularly in regard to its application as a model to study the closely related lentivirus, human immunodeficiency virus (HIV). In particular, FIV and HIV share remarkable structure and sequence organization, utilize parallel modes of receptor-mediated entry, and result in a similar spectrum of immunodeficiency-related diseases due to analogous modes of immune dysfunction. This review summarizes current knowledge of FIV infection kinetics and the mechanisms of immune dysfunction in relation to opportunistic disease, specifically in regard to studying HIV pathogenesis. Furthermore, we present data that highlight changes in the oral microbiota and oral immune system during FIV infection, and outline the potential for the feline model of oral AIDS manifestations to elucidate pathogenic mechanisms of HIV-induced oral disease. Finally, we discuss advances in molecular biology, vaccine development, neurologic dysfunction, and the ability to apply pharmacologic interventions and sophisticated imaging technologies to study experimental and naturally occurring FIV, which provide an excellent, but often overlooked, resource for advancing therapies and the management of HIV/AIDS. PMID:29677122

Endoplasmic Reticulum Stress Activates the Inflammasome via NLRP3- and Caspase-2-Driven Mitochondrial Damage.

PubMed

Bronner, Denise N; Abuaita, Basel H; Chen, Xiaoyun; Fitzgerald, Katherine A; Nuñez, Gabriel; He, Yongqun; Yin, Xiao-Ming; O'Riordan, Mary X D

2015-09-15

Endoplasmic reticulum (ER) stress is observed in many human diseases, often associated with inflammation. ER stress can trigger inflammation through nucleotide-binding domain and leucine-rich repeat containing (NLRP3) inflammasome, which might stimulate inflammasome formation by association with damaged mitochondria. How ER stress triggers mitochondrial dysfunction and inflammasome activation is ill defined. Here we have used an infection model to show that the IRE1α ER stress sensor regulates regulated mitochondrial dysfunction through an NLRP3-mediated feed-forward loop, independently of ASC. IRE1α activation increased mitochondrial reactive oxygen species, promoting NLRP3 association with mitochondria. NLRP3 was required for ER stress-induced cleavage of caspase-2 and the pro-apoptotic factor, Bid, leading to subsequent release of mitochondrial contents. Caspase-2 and Bid were necessary for activation of the canonical inflammasome by infection-associated or general ER stress. These data identify an NLRP3-caspase-2-dependent mechanism that relays ER stress to the mitochondria to promote inflammation, integrating cellular stress and innate immunity. Copyright © 2015 Elsevier Inc. All rights reserved.

Biology and function of adipose tissue macrophages, dendritic cells and B cells.

PubMed

Ivanov, Stoyan; Merlin, Johanna; Lee, Man Kit Sam; Murphy, Andrew J; Guinamard, Rodolphe R

2018-04-01

The increasing incidence of obesity and its socio-economical impact is a global health issue due to its associated co-morbidities, namely diabetes and cardiovascular disease [1-5]. Obesity is characterized by an increase in adipose tissue, which promotes the recruitment of immune cells resulting in low-grade inflammation and dysfunctional metabolism. Macrophages are the most abundant immune cells in the adipose tissue of mice and humans. The adipose tissue also contains other myeloid cells (dendritic cells (DC) and neutrophils) and to a lesser extent lymphocyte populations, including T cells, B cells, Natural Killer (NK) and Natural Killer T (NKT) cells. While the majority of studies have linked adipose tissue macrophages (ATM) to the development of low-grade inflammation and co-morbidities associated with obesity, emerging evidence suggests for a role of other immune cells within the adipose tissue that may act in part by supporting macrophage homeostasis. In this review, we summarize the current knowledge of the functions ATMs, DCs and B cells possess during steady-state and obesity. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of Spaceflight on Venous and Arterial Compliance

NASA Technical Reports Server (NTRS)

Ribeiro, L. C.; Laurie, S. S.; Lee, S. M. C.; Macias, B. R.; Martin, D. S.; Ploutz-Snyder, R.; Stenger, M. B.; Platts, S. H.

2017-01-01

The visual impairment and intracranial pressure (VIIP) syndrome is a spaceflight-associated set of symptoms affecting more than 50% of American astronauts who have flown International Space Station (ISS) missions. VIIP is defined primarily by visual acuity deficits and anatomical changes to eye structures (e.g. optic disc edema, choroidal folds, and globe flattening) and is hypothesized to be related to elevated intracranial pressure secondary to a cephalad fluid shift. However, ocular symptoms have not been replicated in subjects completing prolonged bed rest, a well-accepted spaceflight analog. Altered vascular compliance along with spaceflight factors such as diet, radiation exposure, or environmental factors may cause alterations in the cardiovascular system that contribute to the manifestation of ocular changes. Loss of visual acuity could be a significant threat to crew health and performance during and after an exploration mission and may have implications for years post-flight. The overall objective of this project is to determine if spaceflight alters vascular compliance and whether such an adaptation is related to the incidence of VIIP. This objective will be met by completing three separate but related projects.

Atopic dermatitis and vitamin D: facts and controversies*

PubMed Central

Mesquita, Kleyton de Carvalho; Igreja, Ana Carolina de Souza Machado; Costa, Izelda Maria Carvalho

2013-01-01

Patients with atopic dermatitis have genetically determined risk factors that affect the barrier function of the skin and immune responses that interact with environmental factors. Clinically, this results in an intensely pruriginous and inflamed skin that allows the penetration of irritants and allergens and predisposes patients to colonization and infection by microorganisms. Among the various etiological factors responsible for the increased prevalence of atopic diseases over the past few decades, the role of vitamin D has been emphasized. As the pathogenesis of AD involves a complex interplay of epidermal barrier dysfunction and dysregulated immune response, and vitamin D is involved in both processes, it is reasonable to expect that vitamin D's status could be associated with atopic dermatitis' risk or severity. Such association is suggested by epidemiological and experimental data. In this review, we will discuss the evidence for and against this controversial relationship, emphasizing the possible etiopathogenic mechanisms involved. PMID:24474104

Relationship between adipose tissue dysfunction, vitamin D deficiency and the pathogenesis of non-alcoholic fatty liver disease

PubMed Central

Cimini, Flavia A; Barchetta, Ilaria; Carotti, Simone; Bertoccini, Laura; Baroni, Marco G; Vespasiani-Gentilucci, Umberto; Cavallo, Maria-Gisella; Morini, Sergio

2017-01-01

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. Its pathogenesis is complex and not yet fully understood. Over the years many studies have proposed various pathophysiological hypotheses, among which the currently most widely accepted is the “multiple parallel hits” theory. According to this model, lipid accumulation in the hepatocytes and insulin resistance increase the vulnerability of the liver to many factors that act in a coordinated and cooperative manner to promote hepatic injury, inflammation and fibrosis. Among these factors, adipose tissue dysfunction and subsequent chronic low grade inflammation play a crucial role. Recent studies have shown that vitamin D exerts an immune-regulating action on adipose tissue, and the growing wealth of epidemiological data is demonstrating that hypovitaminosis D is associated with both obesity and NAFLD. Furthermore, given the strong association between these conditions, current findings suggest that vitamin D may be involved in the relationship between adipose tissue dysfunction and NAFLD. The purpose of this review is to provide an overview of recent advances in the pathogenesis of NAFLD in relation to adipose tissue dysfunction, and in the pathophysiology linking vitamin D deficiency with NAFLD and adiposity, together with an overview of the evidence available on the clinical utility of vitamin D supplementation in cases of NAFLD. PMID:28596677

Camel whey protein protects lymphocytes from apoptosis via the PI3K/AKT, NF-κB, ATF-3 and HSP-70 signaling pathways in heat-stressed male mice.

PubMed

Badr, Gamal; Ramadan, Nancy K; Abdel-Tawab, Hanem S; Ahmed, Samia F; Mahmoud, Mohamed H

2017-11-22

Heat stress (HS) is an environmental factor that depresses the immune systems mediating dysfunctional immune cells. Camel whey protein (CWP) can scavenge free radicals and enhance immunity. The present study investigated the impact of dietary supplementation with CWP on immune dysfunction induced by exposure to HS. Male mice (n = 45) were divided into three groups: control group; HS group; and HS mice that were orally administered CWP (HS+CWP group). The HS group exhibited elevated levels of reactive oxygen species (ROS) and pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) as well as a significant reduction in the IL-2 and IL-4 levels. Exposure to HS resulted in impaired AKT and IκB-α phosphorylation; increased ATF-3 and HSP70 expression; and aberrant distribution of CD3+ T cells and CD20+ B cells in the thymus and spleen. Interestingly, HS mice treated with CWP presented significantly restored levels of ROS and pro-inflammatory cytokines near the levels observed in control mice. Furthermore, supplementation of HS mice with CWP enhanced the phosphorylation of AKT and IκB-α; attenuated the expression of ATF-3, HSP70 and HSP90; and improved T and B cell distributions in the thymus and spleen. Our findings reveal a potential immunomodulatory effect of CWP in attenuating immune dysfunction induced by exposure to thermal stress.

Maladaptive immune and inflammatory pathways lead to cardiovascular insulin resistance.

PubMed

Aroor, Annayya R; McKarns, Susan; Demarco, Vincent G; Jia, Guanghong; Sowers, James R

2013-11-01

Insulin resistance is a hallmark of obesity, the cardiorenal metabolic syndrome and type 2 diabetes mellitus (T2DM). The progression of insulin resistance increases the risk for cardiovascular disease (CVD). The significance of insulin resistance is underscored by the alarming rise in the prevalence of obesity and its associated comorbidities in the Unites States and worldwide over the last 40-50 years. The incidence of obesity is also on the rise in adolescents. Furthermore, premenopausal women have lower CVD risk compared to men, but this protection is lost in the setting of obesity and insulin resistance. Although systemic and cardiovascular insulin resistance is associated with impaired insulin metabolic signaling and cardiovascular dysfunction, the mechanisms underlying insulin resistance and cardiovascular dysfunction remain poorly understood. Recent studies show that insulin resistance in obesity and diabetes is linked to a metabolic inflammatory response, a state of systemic and tissue specific chronic low grade inflammation. Evidence is also emerging that there is polarization of macrophages and lymphocytes towards a pro-inflammatory phenotype that contributes to progression of insulin resistance in obesity, cardiorenal metabolic syndrome and diabetes. In this review, we provide new insights into factors, such as, the renin-angiotensin-aldosterone system, sympathetic activation and incretin modulators (e.g., DPP-4) and immune responses that mediate this inflammatory state in obesity and other conditions characterized by insulin resistance. © 2013.

Apollo Soyuz pamphlet No. 7: Biology in zero-G

NASA Technical Reports Server (NTRS)

Page, L. W.; Page, T.

1977-01-01

The effects of weightlessness on small living organisms, and methods for improving biological techniques were investigated in the seven experiments reported in this pamphlet which is intended as a curriculum supplement for secondary schools. Topics include: (1) killfish hatching and orientation; (2) microbial growth and changes in biorhythm; (3) cell separation by electrophoresis; (4) microbial exchange in the space raft; and (5) changes in astronaut immunity during spaceflight. The pamphlet is intended as a curriculum supplement for secondary schools.

Human skeletal muscle protein breakdown during spaceflight

NASA Technical Reports Server (NTRS)

Stein, T. P.; Schluter, M. D.

1997-01-01

Human spaceflight is associated with a loss of body protein. Excretion of 3-methylhistidine (3-MH) in the urine is a useful measurement of myofibrillar protein breakdown. Bed rest, particularly with 6 degrees head-down tilt, is an accepted ground-based model for human spaceflight. The objectives of this report were to compare 3-MH excretion from two Life Sciences shuttle missions (duration 9.5 and 15 days, n = 9) and from 17 days of bed rest (n = 7) with 6 degrees head-down tilt. The bed rest study was designed to mimic an actual Life Sciences spaceflight and so incorporated an extensive battery of physiological tests focused on the musculoskeletal system. Results showed that nitrogen retention, based on excretion of nitrogen in the urine, was reduced during both bed rest [from 22 +/- 1 to 1 +/- 5 mg N x kg(-1) x day(-1) (n = 7; P < 0.05)] and spaceflight [from 57 +/- 9 to 19 +/- 3 mg N x kg(-1) x day(-1) (n = 9; P < 0.05)]. 3-MH excretion was unchanged with either bed rest [pre-bed rest 5.30 +/- 0.29 vs. bed rest 5.71 +/- 0.30 micromol 3-MH x kg(-1) x day(-1), n = 7; P = not significant (NS)] or spaceflight [preflight 4.98 +/- 0.37 vs. 4.59 +/- 0.39 micromol 3-MH x kg(-1) x day(-1) in-flight, n = 9; P = NS]. We conclude that 1) 3-MH excretion was unaffected by spaceflight on the shuttle or with bed rest plus exercise, and 2) because protein breakdown (elevated 3-MH) was increased on Skylab but not on the shuttle, it follows that muscle protein breakdown is not an inevitable consequence of spaceflight.

Experiment K-7-35: Circadian Rhythms and Temperature Regulation During Spaceflight. Part 2; Metabolism

NASA Technical Reports Server (NTRS)

Fuller, C. A.; Dotsenko, M. A.; Korolkov, V. I.; Griffin, D. W.; Stein, T. P.

1994-01-01

Energy expenditure can be regarded as the sum of two components; the basal metabolic rate and the energy costs of activity. Weight loss is usually associated with an energy deficit. A negative energy balance exists when energy intake is less that energy utilization. The deficit is made up by tissue catabolism (principally fat, but also some protein). By analyzing food and water intake, urine and fecal output, and changes in body weight, the Skylab investigators reached the unexpected conclusion that energy expenditure during spaceflight was about 5% greater than at 1 G (Leonard, 1983; Rambaut et al., 1977). Possible explanations for the human metabolic responses are an increased workload during spaceflight (Leonard, 1983), or as Rambaut and co-workers (1977) suggested, a progressive decrease in metabolic efficiency. It is likely to be very difficult to distinguish between these two possibilities in man because the activity component may be different during spaceflight than it is the ground. The problem is to measure energy expenditure with efficient precision during spaceflight in a non-invasive manner which will not interfere with other investigations or take an time. The doubly labeled water (DLW) method meets these criteria. The DLW method is the only method available for continuously measuring energy expenditure during spaceflight given the severely restricted conditions in the spaceflight environment. Therefore, this study focuses on the development and use of this procedure on nonhuman primates during spaceflight. Energy expenditure and total body water was determined in two Rhesus monkeys by the doubly labeled water (2H2'80) method. Three determinations were made. Monkey B (#2483) was studied twice, during the flight of COSMOS 2044 and during a follow-up ground control study a month later. A second monkey was studied on the ground only (Monkey D, #782).

Spaceflight-induced vertebral bone loss in ovariectomized rats is associated with increased bone marrow adiposity and no change in bone formation

PubMed Central

Keune, Jessica A; Philbrick, Kenneth A; Branscum, Adam J; Iwaniec, Urszula T; Turner, Russell T

2016-01-01

There is often a reciprocal relationship between bone marrow adipocytes and osteoblasts, suggesting that marrow adipose tissue (MAT) antagonizes osteoblast differentiation. MAT is increased in rodents during spaceflight but a causal relationship between MAT and bone loss remains unclear. In the present study, we evaluated the effects of a 14-day spaceflight on bone mass, bone resorption, bone formation, and MAT in lumbar vertebrae of ovariectomized (OVX) rats. Twelve-week-old OVX Fischer 344 rats were randomly assigned to a ground control or flight group. Following flight, histological sections of the second lumbar vertebrae (n=11/group) were stained using a technique that allowed simultaneous quantification of cells and preflight fluorochrome label. Compared with ground controls, rats flown in space had 32% lower cancellous bone area and 306% higher MAT. The increased adiposity was due to an increase in adipocyte number (224%) and size (26%). Mineral apposition rate and osteoblast turnover were unchanged during spaceflight. In contrast, resorption of a preflight fluorochrome and osteoclast-lined bone perimeter were increased (16% and 229%, respectively). The present findings indicate that cancellous bone loss in rat lumbar vertebrae during spaceflight is accompanied by increased bone resorption and MAT but no change in bone formation. These findings do not support the hypothesis that increased MAT during spaceflight reduces osteoblast activity or lifespan. However, in the context of ovarian hormone deficiency, bone formation during spaceflight was insufficient to balance increased resorption, indicating defective coupling. The results are therefore consistent with the hypothesis that during spaceflight mesenchymal stem cells are diverted to adipocytes at the expense of forming osteoblasts. PMID:28725730

Chronic lymphocytic leukemia and infection risk in the era of targeted therapies: Linking mechanisms with infections.

PubMed

Hilal, Talal; Gea Banacloche, Juan C; Leis, Jose F

2018-03-16

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in the world. Patient with CLL are at particular risk for infections due to inherent disease-related immune dysfunction in addition to the effect of certain systemic therapies on the immune system. The advent of B-cell receptor (BCR) inhibitors such as ibrutinib and idelalisib has led to a practice change that utilizes these targeted agents in the treatment of CLL, either in place of chemoimmunotherapy (CIT) or in later line settings. In this paper, we review the pathophysiology of immune dysfunction in CLL, the spectrum of immunodeficiency with the various therapeutic agents along with prevention strategies with a focus on targeted therapies. Copyright © 2018 Elsevier Ltd. All rights reserved.

Zinc deficiency enhanced inflammatory response by increasing immune cell activation and inducing IL6 promoter demethylation

PubMed Central

Wong, Carmen P.; Rinaldi, Nicole A.; Ho, Emily

2015-01-01

Scope Zinc deficiency results in immune dysfunction and promotes systemic inflammation. The objective of this study was to examine the effects of zinc deficiency on cellular immune activation and epigenetic mechanisms that promote inflammation. This work is potentially relevant to the aging population given that age-related immune defects, including chronic inflammation, coincide with declining zinc status. Methods and results An in vitro cell culture system and the aged mouse model were used to characterize immune activation and DNA methylation profiles that may contribute to the enhanced proinflammatory response mediated by zinc deficiency. Zinc deficiency up-regulated cell activation markers ICAM1, MHC class II, and CD86 in THP1 cells, that coincided with increased IL1β and IL6 responses following LPS stimulation. A decreased zinc status in aged mice was similarly associated with increased ICAM1 and IL6 gene expression. Reduced IL6 promoter methylation was observed in zinc deficient THP1 cells, as well as in aged mice and human lymphoblastoid cell lines derived from aged individuals. Conclusion Zinc deficiency induced inflammatory response in part by eliciting aberrant immune cell activation and altered promoter methylation. Our results suggested potential interactions between zinc status, epigenetics, and immune function, and how their dysregulation could contribute to chronic inflammation. PMID:25656040

HIV enteropathy and aging: gastrointestinal immunity, mucosal epithelial barrier, and microbial translocation.

PubMed

Wang, Hongyin; Kotler, Donald P

2014-07-01

Despite decreases in morbidity and mortality as a result of antiretroviral therapy, gastrointestinal dysfunction remains common in HIV infection. Treated patients are at risk for complications of 'premature' aging, such as cardiovascular disease, osteopenia, neurocognitive decline, malignancies, and frailty. This review summarizes recent observations in this field. Mucosal CD4 lymphocytes, especially Th17 cells, are depleted in acute HIV and simian immune deficiency virus (SIV) infections, although other cell types also are affected. Reconstitution during therapy often is incomplete, especially in mucosa. Mucosal barrier function is affected by both HIV infection and aging and includes paracellular transport via tight junctions and uptake through areas of apoptosis; other factors may affect systemic antigen exposure. The resultant microbial translocation is associated with systemic immune activation in HIV and SIV infections. There is evidence of immune activation and microbial translocation in the elderly. The immune phenotypes of immunosenescence in HIV infection and aging appear similar. There are several targets for intervention; blockage of residual mucosal virus replication, preventing antigen uptake, modulating the microbiome, improving T cell recovery, combining therapies aimed at mucosal integrity, augmenting mucosal immunity, and managing traditional risk factors for premature aging in the general population. Aging may interact with HIV enteropathy to enhance microbial translocation and immune activation.

Diabetes-associated dry eye syndrome in a new humanized transgenic model of type 1 diabetes.

PubMed

Imam, Shahnawaz; Elagin, Raya B; Jaume, Juan Carlos

2013-01-01

Patients with Type 1 Diabetes (T1D) are at high risk of developing lacrimal gland dysfunction. We have developed a new model of human T1D using double-transgenic mice carrying HLA-DQ8 diabetes-susceptibility haplotype instead of mouse MHC-class II and expressing the human beta cell autoantigen Glutamic Acid Decarboxylase in pancreatic beta cells. We report here the development of dry eye syndrome (DES) after diabetes induction in our humanized transgenic model. Double-transgenic mice were immunized with DNA encoding human GAD65, either naked or in adenoviral vectors, to induce T1D. Mice monitored for development of diabetes developed lacrimal gland dysfunction. Animals developed lacrimal gland disease (classically associated with diabetes in Non Obese Diabetic [NOD] mice and with T1D in humans) as they developed glucose intolerance and diabetes. Animals manifested obvious clinical signs of dry eye syndrome (DES), from corneal erosions to severe keratitis. Histological studies of peri-bulbar areas revealed lymphocytic infiltration of glandular structures. Indeed, infiltrative lesions were observed in lacrimal/Harderian glands within weeks following development of glucose intolerance. Lesions ranged from focal lymphocytic infiltration to complete acinar destruction. We observed a correlation between the severity of the pancreatic infiltration and the severity of the ocular disease. Our results demonstrate development of DES in association with antigen-specific insulitis and diabetes following immunization with clinically relevant human autoantigen concomitantly expressed in pancreatic beta cells of diabetes-susceptible mice. As in the NOD mouse model and as in human T1D, our animals developed diabetes-associated DES. This specific finding stresses the relevance of our model for studying these human diseases. We believe our model will facilitate studies to prevent/treat diabetes-associated DES as well as human diabetes.

Immunosenescence in vertebrates and invertebrates.

PubMed

Müller, Ludmila; Fülöp, Tamas; Pawelec, Graham

2013-04-02

There is an established consensus that it is primarily the adaptive arm of immunity, and the T cell subset in particular, that is most susceptible to the deleterious changes with age known as "immunosenescence". Can we garner any clues as to why this might be by considering comparative immunology and the evolutionary emergence of adaptive and innate immunity? The immune system is assumed to have evolved to protect the organism against pathogens, but the way in which this is accomplished is different in the innate-vs-adaptive arms, and it is unclear why the latter is necessary. Are there special characteristics of adaptive immunity which might make the system more susceptible to age-associated dysfunction? Given recent accumulating findings that actually there are age-associated changes to innate immunity and that these are broadly similar in vertebrates and invertebrates, we suggest here that it is the special property of memory in the adaptive immune system which results in the accumulation of cells with a restricted receptor repertoire, dependent on the immunological history of the individual's exposures to pathogens over the lifetime, and which is commonly taken as a hallmark of "immunosenescence". However, we further hypothesize that this immunological remodelling per se does not necessarily convey a disadvantage to the individual (ie. is not necessarily "senescence" if it is not deleterious). Indeed, under certain circumstances, or potentially even as a rule, this adaptation to the individual host environment may confer an actual survival advantage.

Effects of Spaceflight on Venous and Arterial Compliance

NASA Technical Reports Server (NTRS)

Platts, S. H.; Pibeiro, L. C.; Laurie, S. S.; Lee, S. M. C.; Martin, D. S.; Ploutz-Snyder, R.; Stenger, M. B.

2016-01-01

The visual impairment and intracranial pressure (VIIP) syndrome is a spaceflight-associated medical condition consisting of a constellation of symptoms affecting less than 70% of American astronauts who have flown International Space Station (ISS) missions. VIIP is defined primarily by visual acuity deficits and anatomical changes to eye structures and is hypothesized to be related to elevated intracranial pressure secondary to spaceflight-induced cephalad fluid shifts, although other space flight factors (e.g., diet, environmental factors) may contribute. Loss of visual acuity could be a significant threat to crew health and performance during and after an exploration mission and may have implications for years postflight.

Acute inflammatory neuropathy with monoclonal anti-GM2 IgM antibodies, IgM-κ paraprotein and additional autoimmune processes in association with a diffuse large B-cell non-Hodgkin's lymphoma.

PubMed

Milnik, Annette; Roggenbuck, Dirk; Conrad, Karsten; Bartels, Claudius

2013-01-21

Lymphoproliferative disorders are often associated with autoimmune processes preceding or following the occurrence of a lymphoma. Here, we describe a patient with a history of recurrent diffuse large B-cell non-Hodgkin's lymphoma who suffered from an acute inflammatory neuropathy with specific monoclonal anti-GM2 IgM antibodies and associated IgM-κ paraprotein. It was possible in this case to prove that both, anti-GM2 IgM antibodies and IgM-κ paraprotein, share the same binding characteristic. In addition, the patient possibly suffered from an immune thrombocytopenia and an early-stage bullous pemphigoid with anti-BP-230 IgG antibodies. Intravenous immunoglobulin and plasmapheresis alleviated the acute neuropathy and thrombocytopenia, while the bullous pemphigoid has been aggravated. In summary, the simultaneous occurrence of multiple autoimmune processes was a sign of a dysfunctional immune system preceding the relapse of a B-cell non-Hodgkin's lymphoma.

Molecular Genetic of Atopic dermatitis: An Update

PubMed Central

Al-Shobaili, Hani A.; Ahmed, Ahmed A.; Alnomair, Naief; Alobead, Zeiad Abdulaziz; Rasheed, Zafar

2016-01-01

Atopic dermatitis (AD) is a chronic multifactorial inflammatory skin disease. The pathogenesis of AD remains unclear, but the disease results from dysfunctions of skin barrier and immune response, where both genetic and environmental factors play a key role. Recent studies demonstrate the substantial evidences that show a strong genetic association with AD. As for example, AD patients have a positive family history and have a concordance rate in twins. Moreover, several candidate genes have now been suspected that play a central role in the genetic background of AD. In last decade advanced procedures similar to genome-wide association (GWA) and single nucleotide polymorphism (SNP) have been applied on different population and now it has been clarified that AD is significantly associated with genes of innate/adaptive immune systems, human leukocyte antigens (HLA), cytokines, chemokines, drug-metabolizing genes or various other genes. In this review, we will highlight the recent advancements in the molecular genetics of AD, especially on possible functional relevance of genetic variants discovered to date. PMID:27004062

The effects of spaceflight and Insulin-like Growth Factor-1 on the T-cell and macrophage populations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pecaut, M.J.; Simske, S.J.; Fleshner, M.

Twelve Sprague-Dawley rats were flown aboard the Space Shuttle Endeavor (STS-77) to study the effects of microgravity-induced stress on the immunoskeletal system. Sixteen rats were used as simultaneous vivarium ground controls during the ten day mission. Osmotic pumps, half of which contained Insulin-like Growth Factor-1 (IGF-1, provided by Chiron), were surgically implanted (subcutaneous) into the rats prior to launch in an attempt to counter any stress effects. On the day of landing, the rats were sacrificed and dissected. Splenocytes and thymocytes were labeled with antibodies against CD4, CD8, CD11b, and TCR for flow cytometry. The percentage of splenic cytotoxic/suppressor (TCR+/CD8+)more » T-cells increased significantly (by 118{percent}) in spaceflight. There were also decreases in splenic helper (TCR+/CD4+) T-cells and (CD11b+) macrophages (by 33{percent} and 38{percent}, respectively). Together, these results suggest the stress of spaceflight could cause a significant decrease in the ability of rats to mount an immune response. The effects of IGF-1 on cell population distributions were negligible for both flight and vivarium ground controls. However, there were significant differences in spleen and thymus masses suggesting that while IGF-1 did not effect population distributions, the drug may have caused an increase in population size. {copyright} {ital 1997 American Institute of Physics.}« less

Dynamic Visual Acuity: a Functionally Relevant Research Tool

NASA Technical Reports Server (NTRS)

Peters, Brian T.; Brady, Rachel A.; Miller, Chris A.; Mulavara, Ajitkumar P.; Wood, Scott J.; Cohen, Helen S.; Bloomberg, Jacob J.

2010-01-01

Coordinated movements between the eyes and head are required to maintain a stable retinal image during head and body motion. The vestibulo-ocular reflex (VOR) plays a significant role in this gaze control system that functions well for most daily activities. However, certain environmental conditions or interruptions in normal VOR function can lead to inadequate ocular compensation, resulting in oscillopsia, or blurred vision. It is therefore possible to use acuity to determine when the environmental conditions, VOR function, or the combination of the two is not conductive for maintaining clear vision. Over several years we have designed and tested several tests of dynamic visual acuity (DVA). Early tests used the difference between standing and walking acuity to assess decrements in the gaze stabilization system after spaceflight. Supporting ground-based studies measured the responses from patients with bilateral vestibular dysfunction and explored the effects of visual target viewing distance and gait cycle events on walking acuity. Results from these studies show that DVA is affected by spaceflight, is degraded in patients with vestibular dysfunction, changes with target distance, and is not consistent across the gait cycle. We have recently expanded our research to include studies in which seated subjects are translated or rotated passively. Preliminary results from this work indicate that gaze stabilization ability may differ between similar active and passive conditions, may change with age, and can be affected by the location of the visual target with respect to the axis of motion. Use of DVA as a diagnostic tool is becoming more popular but the functional nature of the acuity outcome measure also makes it ideal for identifying conditions that could lead to degraded vision. By doing so, steps can be taken to alter the problematic environments to improve the man-machine interface and optimize performance.

Nitroaspirin corrects immune dysfunction in tumor-bearing hosts and promotes tumor eradication by cancer vaccination

NASA Astrophysics Data System (ADS)

de Santo, Carmela; Serafini, Paolo; Marigo, Ilaria; Dolcetti, Luigi; Bolla, Manlio; del Soldato, Piero; Melani, Cecilia; Guiducci, Cristiana; Colombo, Mario P.; Iezzi, Manuela; Musiani, Piero; Zanovello, Paola; Bronte, Vincenzo

2005-03-01

Active suppression of tumor-specific T lymphocytes can limit the immune-mediated destruction of cancer cells. Of the various strategies used by tumors to counteract immune attacks, myeloid suppressors recruited by growing cancers are particularly efficient, often resulting in the induction of systemic T lymphocyte dysfunction. We have previously shown that the mechanism by which myeloid cells from tumor-bearing hosts block immune defense strategies involves two enzymes that metabolize L-arginine: arginase and nitric oxide (NO) synthase. NO-releasing aspirin is a classic aspirin molecule covalently linked to a NO donor group. NO aspirin does not possess direct antitumor activity. However, by interfering with the inhibitory enzymatic activities of myeloid cells, orally administered NO aspirin normalized the immune status of tumor-bearing hosts, increased the number and function of tumor-antigen-specific T lymphocytes, and enhanced the preventive and therapeutic effectiveness of the antitumor immunity elicited by cancer vaccination. Because cancer vaccines and NO aspirin are currently being investigated in independent phase I/II clinical trials, these findings offer a rationale to combine these treatments in subjects with advanced neoplastic diseases. arginase | immunosuppression | myeloid cells | nitric oxide | immunotherapy

Cryptococcal osteomyelitis: a report of 5 cases and a review of the recent literature.

PubMed

Medaris, Leigh Ann; Ponce, Brent; Hyde, Zane; Delgado, Dennis; Ennis, David; Lapidus, William; Larrison, Matthew; Pappas, Peter G

2016-06-01

Cryptococcus neoformans is a fungal pathogen associated with advanced HIV disease and other disorders associated with immune dysfunction. The pulmonary and the central nervous system are the most common manifestations of the disease. Localised osteomyelitis as the sole manifestation of extrapulmonary disease is rare. Herein, we present five cases of Cryptococcus osteomyelitis as the only manifestation of extrapulmonary disease. We also identified 84 additional cases of isolated cryptococcal osteomyelitis in the literature. Using these data, we have made some general recommendations regarding an approach to treatment of this uncommon clinical entity. © 2016 Blackwell Verlag GmbH.

Impaired Epstein-Barr Virus-Specific Neutralizing Antibody Response during Acute Infectious Mononucleosis Is Coincident with Global B-Cell Dysfunction

PubMed Central

Panikkar, Archana; Hislop, Andrew; Tellam, Nick; Dasari, Vijayendra; Hogquist, Kristin A.; Wykes, Michelle; Moss, Denis J.; Rickinson, Alan; Balfour, Henry H.

2015-01-01

Here we present evidence for previously unappreciated B-cell immune dysregulation during acute Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM). Longitudinal analyses revealed that patients with acute IM have undetectable EBV-specific neutralizing antibodies and gp350-specific B-cell responses, which were associated with a significant reduction in memory B cells and no evidence of circulating antibody-secreting cells. These observations correlate with dysregulation of tumor necrosis factor family members BAFF and APRIL and increased expression of FAS on circulating B cells. PMID:26109734

Influence of the Timing of Antiretroviral Therapy on the Potential for Normalization of Immune Status in Human Immunodeficiency Virus 1–Infected Individuals

PubMed Central

Okulicz, Jason F.; Le, Tuan D.; Agan, Brian K.; Camargo, Jose F.; Landrum, Michael L.; Wright, Edwina; Dolan, Matthew J.; Ganesan, Anuradha; Ferguson, Tomas M.; Smith, Davey M.; Richman, Douglas D.; Little, Susan J.; Clark, Robert A.; He, Weijing; Ahuja, Sunil K.

2014-01-01

IMPORTANCE In individuals with human immunodeficiency virus 1 (HIV-1) infection who are receiving antiretroviral therapy (ART), factors that promote full immune recovery are not well characterized. OBJECTIVE To investigate the influence of the timing of ART relative to HIV-1 infection on normalization of CD4+ T-cell counts, AIDS risk, and immune function. DESIGN, SETTING, AND PARTICIPANTS Participants in the observational US Military HIV Natural History Study with documented estimated dates of seroconversion (EDS) who achieved virologic suppression with ART were evaluated. Markers indicative of immune activation, dysfunction, and responsiveness were determined. Responses to hepatitis B virus (HBV) vaccine, an indicator of in vivo immune function, were also assessed. The timing of ART was indexed to the EDS and/or entry into the cohort. The CD4+ counts in HIV-1–uninfected populations were surveyed. MAIN OUTCOMES AND MEASURES Normalization of CD4+ counts to 900 cells/μL or higher, AIDS development, HBV vaccine response, as well as T-cell activation, dysfunction, and responsiveness. RESULTS The median CD4+ count in HIV-1–uninfected populations was approximately 900 cells/μL. Among 1119 HIV-1–infected participants, CD4+ normalization was achieved in 38.4% vs 28.3% of those initiating ART within 12 months vs after 12 months from the EDS (P = .001). Incrementally higher CD4+ recovery (<500,500–899, and ≥900 cells/μL) was associated with stepwise decreases in AIDS risk and reversion of markers of immune activation, dysfunction, and responsiveness to levels approximating those found in HIV-1–uninfected persons. Participants with CD4+ counts of 500 cells/μL or higher at study entry (adjusted odds ratio [aOR], 2.00; 95% CI, 1.51–2.64; P < .001) or ART initiation (aOR, 4.08; 95% CI, 3.14–5.30; P < .001) had significantly increased CD4+ normalization rates compared with other participants. However, even among individuals with a CD4+ count of 500 cells/μL or higher at both study entry and before ART, the odds of CD4+ normalization were 80% lower in those initiating ART after 12 months from the EDS and study entry (aOR, 0.20; 95% CI, 0.07–0.53; P = 001). Initiation of ART within 12 months of EDS vs later was associated with a significantly lower risk of AIDS (7.8% vs 15.3%; P = .002), reduced T-cell activation (percent CD4+HLA-DR+ effector memory T cells, 12.0% vs 15.6%; P = .03), and increased responsiveness to HBV vaccine (67.9% vs 50.9%; P = .07). CONCLUSIONS AND RELEVANCE Deferral of ART beyond 12 months of the EDS diminishes the likelihood of restoring immunologic health in HIV-1–infected individuals. PMID:25419650

Spaceflight and protein metabolism, with special reference to humans

NASA Technical Reports Server (NTRS)

Stein, T. P.; Gaprindashvili, T.

1994-01-01

Human space missions have shown that human spaceflight is associated with a loss of body protein. Specific changes include a loss of lean body mass, decreased muscle mass in the calves, decreased muscle strength, and changes in plasma proteins and amino acids. The major muscle loss is believed to be associated with the antigravity (postural) muscle. The most significant loss of protein appears to occur during the first month of flight. The etiology is believed to be multifactorial with contributions from disuse atrophy, undernutrition, and a stress type of response. This article reviews the results of American and Russian space missions to investigate this problem in humans, monkeys, and rats. The relationship of the flight results with ground-based models including bedrest for humans and hindlimb unweighting for rats is also discussed. The results suggest that humans adapt to spaceflight much better than either monkeys or rats.

Jet fuel-induced immunotoxicity.

PubMed

Harris, D T; Sakiestewa, D; Titone, D; Robledo, R F; Young, R S; Witten, M

2000-09-01

Chronic exposure to jet fuel has been shown to cause human liver dysfunction, emotional dysfunction, abnormal electroencephalograms, shortened attention spans, and to decrease sensorimotor speed (3-5). Exposure to potential environmental toxicants such as jet fuel may have significant effects on host systems beyond those readily visible (e.g., physiology, cardiology, respiratory, etc.), e.g., the immune system. Significant changes in immune function, even if short-lived, may have serious consequences for the exposed host that may impinge affect susceptibility to infectious agents. Major alterations in immune function that are long lasting may result in an increased likelihood of development and/or progression of cancer, as well as autoimmune diseases. In the current study mice were exposed 1 h/day for 7 days to a 1000-mg/m3 concentration of aerosolized jet fuel obtained from various sources (JP-8, JP-8+100 and Jet A1) and of differing compositions to simulate occupational exposures. Twenty-four hours after the last exposure the mice were analyzed for effects on the immune system. It was observed that exposure to all jet fuel sources examined had detrimental effects on the immune system. Decreases in viable immune cell numbers and immune organ weights were found. Jet fuel exposure resulted in differential losses of immune cell populations in the thymus. Further, jet fuel exposure resulted in significantly decreased immune function, as analyzed by mitogenesis assays. Suppressed immune function could not be overcome by the addition of exogenous growth factors known to stimulate immune function. Thus, short-term, low-concentration exposure of mice to aerosolized jet fuel, regardless of source or composition, caused significant deleterious effects on the immune system.

Endothelial dysfunction in dengue virus pathology.

PubMed

Vervaeke, Peter; Vermeire, Kurt; Liekens, Sandra

2015-01-01

Dengue virus (DENV) is a leading cause of illness and death, mainly in the (sub)tropics, where it causes dengue fever and/or the more serious diseases dengue hemorrhagic fever and dengue shock syndrome that are associated with changes in vascular permeability. Despite extensive research, the pathogenesis of DENV is still poorly understood and, although endothelial cells represent the primary fluid barrier of the blood vessels, the extent to which these cells contribute to DENV pathology is still under debate. The primary target cells for DENV are dendritic cells and monocytes/macrophages that release various chemokines and cytokines upon infection, which can activate the endothelium and are thought to play a major role in DENV-induced vascular permeability. However, recent studies indicate that DENV also replicates in endothelial cells and that DENV-infected endothelial cells may directly contribute to viremia, immune activation, vascular permeability and immune targeting of the endothelium. Also, the viral non-structural protein-1 and antibodies directed against this secreted protein have been reported to be involved in endothelial cell dysfunction. This review provides an extensive overview of the effects of DENV infection on endothelial cell physiology and barrier function. Copyright © 2014 John Wiley & Sons, Ltd.

Maternal exposure to silver nanoparticles are associated with behavioral abnormalities in adulthood: Role of mitochondria and innate immunity in developmental toxicity.

PubMed

Amiri, Shayan; Yousefi-Ahmadipour, Aliakbar; Hosseini, Mir-Jamal; Haj-Mirzaian, Arya; Momeny, Majid; Hosseini-Chegeni, Heshmat; Mokhtari, Tahmineh; Kharrazi, Sharmin; Hassanzadeh, Gholamreza; Amini, Seyed Mohammad; Jafarinejad, Somayeh; Ghazi-Khansari, Mahmoud

2018-05-01

Silver nanoparticles (Ag-NPs) are currently used in a wide range of consumer products. Considering the small size of Ag-NPs, they are able to pass through variety of biological barriers and exert their effects. In this regard, the unique physicochemical properties of Ag-NPs along with its high application in the industry have raised concerns about their negative effects on human health. Therefore, it investigated whether prenatal exposure to low doses of Ag-NPs is able to induce any abnormality in the cognitive and behavioral performance of adult offspring. We gavaged pregnant NMRI mice with, 1) Deionized water as vehicle, 2) Ag-NPs 10 nm (0.26 mg/kg/day), 3) Ag-NPs 30 nm (0.26 mg/kg/day), and 4) AgNO 3 (0.26 mg/kg/day) from gestational day (GD) 0 until delivery day. At the postnatal day (PD) 1, our results showed that high concentration of silver is present in the brain of pups. Further, we observed mitochondrial dysfunction and upregulation of the genes relevant to innate immune system in the brain. At PD 60, results revealed that prenatal exposure to Ag-NPs provoked severe cognitive and behavioral abnormalities in male offspring. In addition, we found that prenatal exposure to Ag-NPs was associated with abnormal mitochondrial function and significant up-regulation of the genes relevant to innate immunity in the brain. Although the Ag-NPs have been considered as safe compounds at low doses, our results indicate that prenatal exposure to low doses of Ag-NPs is able to induce behavioral and cognitive abnormalities in adulthood. Also, we found that these effects are at least partly associated with hippocampal mitochondrial dysfunction and the activation of sterile inflammation during early stages of life. Copyright © 2018 Elsevier B.V. All rights reserved.

Reduced sTWEAK and Increased sCD163 Levels in HIV-Infected Patients: Modulation by Antiretroviral Treatment, HIV Replication and HCV Co-Infection

PubMed Central

Beltrán, Luis M.; García Morillo, José S.; Egido, Jesús; Noval, Manuel Leal; Ferrando-Martinez, Sara; Blanco-Colio, Luis M.; Genebat, Miguel; Villar, José R.; Moreno-Luna, Rafael; Moreno, Juan Antonio

2014-01-01

Background Patients infected with the human immunodeficiency virus (HIV) have an increased risk of cardiovascular disease due to increased inflammation and persistent immune activation. CD163 is a macrophage scavenger receptor that is involved in monocyte-macrophage activation in HIV-infected patients. CD163 interacts with TWEAK, a member of the TNF superfamily. Circulating levels of sTWEAK and sCD163 have been previously associated with cardiovascular disease, but no previous studies have fully analyzed their association with HIV. Objective The aim of this study was to analyze circulating levels of sTWEAK and sCD163 as well as other known markers of inflammation (hsCRP, IL-6 and sTNFRII) and endothelial dysfunction (sVCAM-1 and ADMA) in 26 patients with HIV before and after 48 weeks of antiretroviral treatment (ART) and 23 healthy subjects. Results Patients with HIV had reduced sTWEAK levels and increased sCD163, sVCAM-1, ADMA, hsCRP, IL-6 and sTNFRII plasma concentrations, as well as increased sCD163/sTWEAK ratio, compared with healthy subjects. Antiretroviral treatment significantly reduced the concentrations of sCD163, sVCAM-1, hsCRP and sTNFRII, although they remained elevated when compared with healthy subjects. Antiretroviral treatment had no effect on the concentrations of ADMA and sTWEAK, biomarkers associated with endothelial function. The use of protease inhibitors as part of antiretroviral therapy and the presence of HCV-HIV co-infection and/or active HIV replication attenuated the ART-mediated decrease in sCD163 plasma concentrations. Conclusion HIV-infected patients showed a proatherogenic profile characterized by increased inflammatory, immune-activation and endothelial-dysfunction biomarkers that partially improved after ART. HCV-HIV co-infection and/or active HIV replication enhanced immune activation despite ART. PMID:24594990

Preeclampsia and health risks later in life: an immunological link.

PubMed

Cheng, Shi-Bin; Sharma, Surendra

2016-11-01

Pregnancy represents a period of physiological stress, and although this stress is experienced for a very modest portion of life, it is now recognized as a window to women's future health, often by unmasking predispositions to conditions that only become symptomatic later in life. In normal pregnancy, the mother experiences mild metabolic syndrome-like condition through week 20 of gestation. A pronounced phenotype of metabolic syndrome may program pregnancy complications such as preeclampsia. Preeclampsia is a serious complication with a myriad of manifestations for mother and offspring. This pregnancy syndrome is a polygenic disease and has been now linked to higher incidence of cardiovascular disease, diabetes, and several other disorders associated with vulnerable organs. Furthermore, the offspring born to preeclamptic mothers also exhibit an elevated risk of cardiovascular disease, stroke, and mental disorders during adulthood. This suggests that preeclampsia not only exposes the mother and the fetus to complications during pregnancy but also programs chronic diseases in later life. The etiology of preeclampsia is thought to be primarily associated with poor placentation and entails excessive maternal inflammation and endothelial dysfunction. It is well established now that the maternal immune system and the placenta are involved in a highly choreographed cross-talk that underlies adequate spiral artery remodeling required for uteroplacental perfusion and free flow of nutrients to the fetus. Since normal pregnancy is associated with a sequence of events represented by temporal events of inflammation (implantation), anti-inflammation (gestation), and inflammation (parturition), it is quite possible that unscheduled alterations in these regulatory responses may lead to pathologic consequences. Although it is not clear whether immunological alterations occur early in pregnancy, it is proposed that dysregulated systemic and placental immunity contribute to impaired angiogenesis and the onset of preeclampsia. This review will focus on important aspects of the immune system that coordinate with placental dysfunction to program preeclampsia and influence health in later life.

KENNEDY SPACE CENTER, FLA. - (From left) Brian Duffy, Lockheed Martin vice president/associate program manager, Mildred Carter and Col. (Ret.) Herbert E. Carter, one of the Tuskegee Airmen, attend a dinner sponsored by the KSC Spaceflight and Life Sciences Office. Col. Carter was a guest speaker at the dinner.

NASA Image and Video Library

2003-07-18

KENNEDY SPACE CENTER, FLA. - (From left) Brian Duffy, Lockheed Martin vice president/associate program manager, Mildred Carter and Col. (Ret.) Herbert E. Carter, one of the Tuskegee Airmen, attend a dinner sponsored by the KSC Spaceflight and Life Sciences Office. Col. Carter was a guest speaker at the dinner.

Co-immunization with DNA and protein mixture: a safe and efficacious immunotherapeutic strategy for Alzheimer's disease in PDAPP mice.

PubMed

Liu, Si; Shi, DanYang; Wang, Hai-Chao; Yu, Yun-Zhou; Xu, Qing; Sun, Zhi-Wei

2015-01-14

Active immunotherapy targeting β-amyloid (Aβ) is the most promising strategy to prevent or treat Alzheimer's disease (AD). Based on pre-clinical studies and clinical trials, a safe and effective AD vaccine requires a delicate balance between providing therapeutically adequate anti-Aβ antibodies and eliminating or suppressing unwanted adverse T cell-mediated inflammatory reactions. We describe here the immunological characterization and protective efficacy of co-immunization with a 6Aβ15-T DNA and protein mixture without adjuvant as an AD immunotherapeutic strategy. Impressively, this co-immunization induced robust Th2-polarized Aβ-specific antibodies while simultaneously suppressed unwanted inflammatory T cell reactions and avoiding Aβ42-specific T cell-mediated autoimmune responses in immunized mice. Co-immunization with the DNA + protein vaccine could overcome Aβ42-associated hypo-responsiveness and elicit long-term Aβ-specific antibody responses, which helped to maintain antibody-mediated clearance of amyloid and accordingly alleviated AD symptoms in co-immunized PDAPP mice. Our DNA and protein combined vaccine, which could induce an anti-inflammatory Th2 immune response with high level Aβ-specific antibodies and low level IFN-γ production, also demonstrated the capacity to inhibit amyloid accumulation and prevent cognitive dysfunction. Hence, co-immunization with antigen-matched DNA and protein may represent a novel and efficacious strategy for AD immunotherapy to eliminate T cell inflammatory reactions while retaining high level antibody responses.

Effects of Spaceflight on Molecular and Cellular Responses to Bleomycin-induced DNA Damages in Confluent Human Fibroblasts

NASA Astrophysics Data System (ADS)

Lu, Tao; Wu, Honglu; Karouia, Fathi; Stodieck, Louis; Zhang, Ye; Wong, Michael

2016-07-01

Spaceflights expose human beings to various risk factors. Among them are microgravity related physiological stresses in immune, cytoskeletal, and cardiovascular systems, and space radiation related elevation of cancer risk. Cosmic radiation consists of energetic protons and other heavier charged particles that induce DNA damages. Effective DNA damage response and repair mechanism is important to maintain genomic integrity and reduce cancer risk. There were studies on effects of spaceflight and microgravity on DNA damage response in cell and animal models, but the published results were mostly conflicting and inconsistent. To investigate effects of spaceflight on molecular and cellular responses to DNA damages, bleomycin, an anti-cancer drug and radiomimetic reagent, was used to induce DNA damages in confluent human fibroblasts flown to the International Space Station (ISS) and on ground. After exposure to 1.0 mg/ml bleomycin for 3 hours, cells were fixed for immunofluorescence assays and for RNA preparation. Extents of DNA damages were quantified by focus pattern and focus number counting of phosphorylated histone protein H2AX (γg-H2AX). The cells on the ISS showed modestly increased average focus counts per nucleus while the distribution of patterns was similar to that on the ground. PCR array analysis showed that expressions of several genes, including CDKN1A and PCNA, were significantly changed in response to DNA damages induced by bleomycin in both flight and ground control cells. However, there were no significant differences in the overall expression profiles of DNA damage response genes between the flight and ground samples. Analysis of cellular proliferation status with Ki-67 staining showed a slightly higher proliferating population in cells on the ISS than those on ground. Our results suggested that the difference in γg-H2AX focus counts between flight and ground was due to the higher percentage of proliferating cells in space, but spaceflight did not significantly affect initial transcriptional responses to bleomycin treatment in the selected genes in the DNA damage signaling pathways.

Gene, Immune and Cellular Responses to Single and Combined Space Flight Conditions-B (TripleLux-B):

NASA Image and Video Library

2015-03-31

ISS043E070945 (03/31/2015) --- ESA (European Space Agency) astronaut Samantha Cristoforetti, Expedition 43 flight engineer aboard the International Space Station, is seen working on a science experiment that includes photographic documentation of Cellular Responses to Single and Combined Space Flight Conditions. Some effects of the space environment level appear to act at the cellular level and it is important to understand the underlying mechanisms of these effects. This science project uses invertebrate hemocytes to focus on two aspects of cellular function which may have medical importance. The synergy between the effects of the space radiation environment and microgravity on cellular function is the goal of this experiment along with studying the impairment of immune functions under spaceflight conditions.

Subject anxiety and psychological considerations for centrifuge-simulated suborbital spaceflight.

PubMed

Mulcahy, Robert A; Blue, Rebecca S; Vardiman, Johnené L; Mathers, Charles H; Castleberry, Tarah L; Vanderploeg, James M

2014-08-01

Anxiety and psychological concerns may pose a challenge to future commercial spaceflight. To help identify potential measures of anxiousness and indicators of flight-related stress, the psychiatric histories and anxiousness responses of volunteers exposed to G forces in centrifuge-simulated spaceflight acceleration profiles were examined. Over 2 d, 86 individuals (63 men, 23 women), 20-78 yr old, underwent up to 7 centrifuge runs. Day 1 consisted of two +G(z) runs (peak = +3.5 G(z)) and two +Gx runs (peak = +6.0 G(x)). Day 2 consisted of three runs approximating suborbital spaceflight profiles (combined +G(x) and +G(z)). Hemodynamic data were collected during the profiles. Subjects completed a retrospective self-report anxiety questionnaire. Medical monitors identified individuals exhibiting varying degrees of anxiousness during centrifuge exposure, medical histories of psychiatric disease, and other potential indicators of psychological intolerance of spaceflight. The retrospective survey identified 18 individuals self-reporting anxiousness, commonly related to unfamiliarity with centrifuge acceleration and concerns regarding medical history. There were 12 individuals (5 men, 7 women, average age 46.2 yr) who were observed to have anxiety that interfered with their ability to complete training; of these, 4 reported anxiousness on their questionnaire and 9 ultimately completed the centrifuge profiles. Psychiatric history was not significantly associated with anxious symptoms. Anxiety is likely to be a relevant and potentially disabling problem for commercial spaceflight participants; however, positive psychiatric history and self-reported symptoms did not predict anxiety during centrifuge performance. Symptoms of anxiousness can often be ameliorated through training and coaching. Even highly anxious individuals are likely capable of tolerating commercial spaceflight.

Spaceflight Effect on White Matter Structural Integrity

NASA Technical Reports Server (NTRS)

Lee, Jessica K.; Kopplemans, Vincent; Paternack, Ofer; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.; Seidler, Rachael D.

2017-01-01

Recent reports of elevated brain white matter hyperintensity (WMH) counts and volume in postflight astronaut MRIs suggest that further examination of spaceflight's impact on the microstructure of brain white matter is warranted. To this end, retrospective longitudinal diffusion-weighted MRI scans obtained from 15 astronauts were evaluated. In light of the recent reports of microgravity-induced cephalad fluid shift and gray matter atrophy seen in astronauts, we applied a technique to estimate diffusion tensor imaging (DTI) metrics corrected for free water contamination. This approach enabled the analysis of white matter tissue-specific alterations that are unrelated to fluid shifts, occurring from before spaceflight to after landing. After spaceflight, decreased fractional anisotropy (FA) values were detected in an area encompassing the superior and inferior longitudinal fasciculi and the inferior fronto-occipital fasciculus. Increased radial diffusivity (RD) and decreased axial diffusivity (AD) were also detected within overlapping regions. In addition, FA values in the corticospinal tract decreased and RD measures in the precentral gyrus white matter increased from before to after flight. The results show disrupted structural connectivity of white matter in tracts involved in visuospatial processing, vestibular function, and movement control as a result of spaceflight. The findings may help us understand the structural underpinnings of the extensive spaceflight-induced sensorimotor remodeling. Prospective longitudinal assessment of the white matter integrity in astronauts is needed to characterize the evolution of white matter microstructural changes associated with spaceflight, their behavioral consequences, and the time course of recovery. Supported by a grant from the National Space Biomedical Research Institute, NASA NCC 9-58.

Comparative transcriptomics indicate changes in cell wall organization and stress response in seedlings during spaceflight.

PubMed

Johnson, Christina M; Subramanian, Aswati; Pattathil, Sivakumar; Correll, Melanie J; Kiss, John Z

2017-08-21

Plants will play an important role in the future of space exploration as part of bioregenerative life support. Thus, it is important to understand the effects of microgravity and spaceflight on gene expression in plant development. We analyzed the transcriptome of Arabidopsis thaliana using the Biological Research in Canisters (BRIC) hardware during Space Shuttle mission STS-131. The bioinformatics methods used included RMA (robust multi-array average), MAS5 (Microarray Suite 5.0), and PLIER (probe logarithmic intensity error estimation). Glycome profiling was used to analyze cell wall composition in the samples. In addition, our results were compared to those of two other groups using the same hardware on the same mission (BRIC-16). In our BRIC-16 experiments, we noted expression changes in genes involved in hypoxia and heat shock responses, DNA repair, and cell wall structure between spaceflight samples compared to the ground controls. In addition, glycome profiling supported our expression analyses in that there was a difference in cell wall components between ground control and spaceflight-grown plants. Comparing our studies to those of the other BRIC-16 experiments demonstrated that, even with the same hardware and similar biological materials, differences in results in gene expression were found among these spaceflight experiments. A common theme from our BRIC-16 space experiments and those of the other two groups was the downregulation of water stress response genes in spaceflight. In addition, all three studies found differential regulation of genes associated with cell wall remodeling and stress responses between spaceflight-grown and ground control plants. © 2017 Botanical Society of America.

Association between Plasma Levels of Transforming Growth Factor-beta1, IL-23 and IL-17 and the Severity of Autism in Egyptian Children

ERIC Educational Resources Information Center

Hashim, Haitham; Abdelrahman, Hadeel; Mohammed, Doaa; Karam, Rehab

2013-01-01

It has been recently shown that dysregulation of transforming growth factor-beta1 (TGF-beta1), IL-23 and IL-17 has been identified as a major factor involved in autoimmune disorders. Based on the increasing evidence of immune dysfunction in autism the aim of this study was to measure serum levels of TGF-beta1, IL-23 and IL-17 in relation to the…

The Impact of Exercising During Haemodialysis on Blood Pressure, Markers of Cardiac Injury and Systemic Inflammation--Preliminary Results of a Pilot Study.

PubMed

Dungey, Maurice; Bishop, Nicolette C; Young, Hannah M L; Burton, James O; Smith, Alice C

2015-01-01

Patients requiring haemodialysis have cardiovascular and immune dysfunction. Little is known about the acute effects of exercise during haemodialysis. Exercise has numerous health benefits but in other populations has a profound impact upon blood pressure, inflammation and immune function; therefore having the potential to exacerbate cardiovascular and immune dysfunction in this vulnerable population. Fifteen patients took part in a randomised-crossover study investigating the effect of a 30-min bout of exercise during haemodialysis compared to resting haemodialysis. We assessed blood pressure, plasma markers of cardiac injury and systemic inflammation and neutrophil degranulation. Exercise increased blood pressure immediately post-exercise; however, 1 hour after exercise blood pressure was lower than resting levels (106±22 vs. 117±25 mm Hg). No differences in h-FABP, cTnI, myoglobin or CKMB were observed between trial arms. Exercise did not alter circulating concentrations of IL-6, TNF-α or IL-1ra nor clearly suppress neutrophil function. This study demonstrates fluctuations in blood pressure during haemodialysis in response to exercise. However, since the fall in blood pressure occurred without evidence of cardiac injury, we regard it as a normal response to exercise superimposed onto the haemodynamic response to haemodialysis. Importantly, exercise did not exacerbate systemic inflammation or immune dysfunction; intradialytic exercise was well tolerated. © 2015 The Author(s) Published by S. Karger AG, Basel.

Circadian misalignment affects sleep and medication use before and during spaceflight

PubMed Central

Flynn-Evans, Erin E; Barger, Laura K; Kubey, Alan A; Sullivan, Jason P; Czeisler, Charles A

2016-01-01

Sleep deficiency and the use of sleep-promoting medication are prevalent during spaceflight. Operations frequently dictate work during the biological night and sleep during the biological day, which contribute to circadian misalignment. We investigated whether circadian misalignment was associated with adverse sleep outcomes before (preflight) and during spaceflight missions aboard the International Space Station (ISS). Actigraphy and photometry data for 21 astronauts were collected over 3,248 days of long-duration spaceflight on the ISS and 11 days prior to launch (n=231 days). Sleep logs, collected one out of every 3 weeks in flight and daily on Earth, were used to determine medication use and subjective ratings of sleep quality. Actigraphy and photometry data were processed using Circadian Performance Simulation Software to calculate the estimated endogenous circadian temperature minimum. Sleep episodes were classified as aligned or misaligned relative to the estimated endogenous circadian temperature minimum. Mixed-effects regression models accounting for repeated measures were computed by data collection interval (preflight, flight) and circadian alignment status. The estimated endogenous circadian temperature minimum occurred outside sleep episodes on 13% of sleep episodes during preflight and on 19% of sleep episodes during spaceflight. The mean sleep duration in low-Earth orbit on the ISS was 6.4±1.2 h during aligned and 5.4±1.4 h (P<0.01) during misaligned sleep episodes. During aligned sleep episodes, astronauts rated their sleep quality as significantly better than during misaligned sleep episodes (66.8±17.7 vs. 60.2±21.0, P<0.01). Sleep-promoting medication use was significantly higher during misaligned (24%) compared with aligned (11%) sleep episodes (P<0.01). Use of any medication was significantly higher on days when sleep episodes were misaligned (63%) compared with when sleep episodes were aligned (49%; P<0.01). Circadian misalignment is associated with sleep deficiency and increased medication use during spaceflight. These findings suggest that there is an immediate need to deploy and assess effective countermeasures to minimize circadian misalignment and consequent adverse sleep outcomes both before and during spaceflight. PMID:28725719

Circadian misalignment affects sleep and medication use before and during spaceflight.

PubMed

Flynn-Evans, Erin E; Barger, Laura K; Kubey, Alan A; Sullivan, Jason P; Czeisler, Charles A

2016-01-01

Sleep deficiency and the use of sleep-promoting medication are prevalent during spaceflight. Operations frequently dictate work during the biological night and sleep during the biological day, which contribute to circadian misalignment. We investigated whether circadian misalignment was associated with adverse sleep outcomes before (preflight) and during spaceflight missions aboard the International Space Station (ISS). Actigraphy and photometry data for 21 astronauts were collected over 3,248 days of long-duration spaceflight on the ISS and 11 days prior to launch ( n =231 days). Sleep logs, collected one out of every 3 weeks in flight and daily on Earth, were used to determine medication use and subjective ratings of sleep quality. Actigraphy and photometry data were processed using Circadian Performance Simulation Software to calculate the estimated endogenous circadian temperature minimum. Sleep episodes were classified as aligned or misaligned relative to the estimated endogenous circadian temperature minimum. Mixed-effects regression models accounting for repeated measures were computed by data collection interval (preflight, flight) and circadian alignment status. The estimated endogenous circadian temperature minimum occurred outside sleep episodes on 13% of sleep episodes during preflight and on 19% of sleep episodes during spaceflight. The mean sleep duration in low-Earth orbit on the ISS was 6.4±1.2 h during aligned and 5.4±1.4 h ( P <0.01) during misaligned sleep episodes. During aligned sleep episodes, astronauts rated their sleep quality as significantly better than during misaligned sleep episodes (66.8±17.7 vs. 60.2±21.0, P <0.01). Sleep-promoting medication use was significantly higher during misaligned (24%) compared with aligned (11%) sleep episodes ( P <0.01). Use of any medication was significantly higher on days when sleep episodes were misaligned (63%) compared with when sleep episodes were aligned (49%; P <0.01). Circadian misalignment is associated with sleep deficiency and increased medication use during spaceflight. These findings suggest that there is an immediate need to deploy and assess effective countermeasures to minimize circadian misalignment and consequent adverse sleep outcomes both before and during spaceflight.

Local activation of p53 in the tumor microenvironment overcomes immune suppression and enhances antitumor immunity

PubMed Central

Guo, Gang; Yu, Miao; Xiao, Wei; Celis, Esteban; Cui, Yan

2017-01-01

Mutations in tumor suppressor p53 remain a vital mechanism of tumor escape from apoptosis and senescence. Emerging evidence suggests that p53 dysfunction also fuels inflammation and supports tumor immune evasion, thereby serving as an immunological driver of tumorigenesis. Therefore, targeting p53 in the tumor microenvironment (TME) also represents an immunologically desirable strategy for reversing immunosuppression and enhancing antitumor immunity. Using a pharmacological p53 activator nutlin-3a, we show that local p53 activation in TME comprising overt tumor infiltrating leukocytes (TILeus) induces systemic antitumor immunity and tumor regression, but not in TME with scarce TILeus, such as B16 melanoma. Maneuvers that recruit leukocytes to TME, such as TLR3 ligand in B16 tumors, greatly enhanced nutlin-induced antitumor immunity and tumor control. Mechanistically, nutlin-3a-induced antitumor immunity was contingent on two non-redundant but immunologically synergistic p53-dependent processes: reversal of immunosuppression in TME and induction of tumor immunogenic cell death (ICD), leading to activation and expansion of polyfunctional CD8 CTLs and tumor regression. Our study demonstrates that unlike conventional tumoricidal therapies, which rely on effective p53 targeting in each tumor cell and often associate with systemic toxicity, this immune-based strategy requires only limited local p53 activation to alter the immune landscape of TME and subsequently amplify immune response to systemic antitumor immunity. Hence, targeting the p53 pathway in TME can be exploited to reverse immunosuppression and augment therapeutic benefits beyond tumoricidal effects to harness tumor-specific, durable, and systemic antitumor immunity with minimal toxicity. PMID:28280037

The immune system and the remodeling infarcted heart: cell biological insights and therapeutic opportunities

PubMed Central

Frangogiannis, Nikolaos G

2014-01-01

Extensive necrosis of ischemic cardiomyocytes in the infarcted myocardium activates the innate immune response triggering an intense inflammatory reaction. Release of danger signals from dying cells and damaged matrix activates the complement cascade and stimulates Toll-Like Receptor (TLR)/Interleukin (IL)-1 signaling, resulting in activation of the Nuclear Factor (NF)-κB system and induction of chemokines, cytokines and adhesion molecules. Subsequent infiltration of the infarct with neutrophils and mononuclear cells serves to clear the wound from dead cells and matrix debris, while stimulating reparative pathways. In addition to its role in repair of the infarcted heart and formation of a scar, the immune system is also involved in adverse remodeling of the infarcted ventricle. Overactive immune responses and defects in suppression, containment and resolution of the post-infarction inflammatory reaction accentuate dilative remodeling in experimental models and may be associated with chamber dilation, systolic dysfunction and heart failure in patients surviving a myocardial infarction. Interventions targeting the inflammatory response to attenuate adverse remodeling may hold promise in patients with myocardial infarction that exhibit accentuated, prolonged, or dysregulated immune responses to the acute injury. PMID:24072174

Immunomodulatory effects of fluoxetine: A new potential pharmacological action for a classic antidepressant drug?

PubMed

Di Rosso, María Emilia; Palumbo, María Laura; Genaro, Ana María

2016-07-01

Selective serotonin reuptake inhibitors are frequently used antidepressants. In particular, fluoxetine is usually chosen for the treatment of the symptoms of depression, obsessive-compulsive, panic attack and bulimia nervosa. Antidepressant therapy has been associated with immune dysfunction. However, there is contradictory evidence about the effect of fluoxetine on the immune system. Experimental findings indicate that lymphocytes express the serotonin transporter. Moreover it has been shown that fluoxetine is able to modulate the immune function through a serotonin-dependent pathway and through a novel independent mechanism. In addition, several studies have shown that fluoxetine can alter tumor cell viability. Thus, it was recently demonstrated in vivo that chronic fluoxetine treatment inhibits tumor growth by increasing antitumor T-cell activity. Here we briefly review some of the literature referring to how fluoxetine is able to modify, for better or worse, the functionality of the immune system. These results of our analysis point to the relevance of the novel pharmacological action of this drug as an immunomodulator helping to treat several pathologies in which immune deficiency and/or deregulation is present. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pathological Type-2 Immune Response, Enhanced Tumor Growth, and Glucose Intolerance in Retnlβ (RELMβ) Null Mice: A Model of Intestinal Immune System Dysfunction in Disease Susceptibility.

PubMed

Wernstedt Asterholm, Ingrid; Kim-Muller, Ja Young; Rutkowski, Joseph M; Crewe, Clair; Tao, Caroline; Scherer, Philipp E

2016-09-01

Resistin, and its closely related homologs, the resistin-like molecules (RELMs) have been implicated in metabolic dysregulation, inflammation, and cancer. Specifically, RELMβ, expressed predominantly in the goblet cells in the colon, is released both apically and basolaterally, and is hence found in both the intestinal lumen in the mucosal layer as well as in the circulation. RELMβ has been linked to both the pathogenesis of colon cancer and type 2 diabetes. RELMβ plays a complex role in immune system regulation, and the impact of loss of function of RELMβ on colon cancer and metabolic regulation has not been fully elucidated. We therefore tested whether Retnlβ (mouse ortholog of human RETNLβ) null mice have an enhanced or reduced susceptibility for colon cancer as well as metabolic dysfunction. We found that the lack of RELMβ leads to increased colonic expression of T helper cell type-2 cytokines and IL-17, associated with a reduced ability to maintain intestinal homeostasis. This defect leads to an enhanced susceptibility to the development of inflammation, colorectal cancer, and glucose intolerance. In conclusion, the phenotype of the Retnlβ null mice unravels new aspects of inflammation-mediated diseases and strengthens the notion that a proper intestinal barrier function is essential to sustain a healthy phenotype. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Neutrophil subsets and their gene signature associate with vascular inflammation and coronary atherosclerosis in lupus

PubMed Central

Carlucci, Philip M.; Purmalek, Monica M.; Dey, Amit K.; Temesgen-Oyelakin, Yenealem; Sakhardande, Simantini; Joshi, Aditya A.; Lerman, Joseph B.; Fike, Alice; Davis, Michael; Chung, Jonathan H.; Playford, Martin P.; Naqi, Mohammad; Mistry, Pragnesh; Gutierrez-Cruz, Gustavo; Dell’Orso, Stefania; Naz, Faiza; Salahuddin, Taufiq; Natarajan, Balaji; Tsai, Wanxia L.; Gupta, Sarthak; Grayson, Peter; Chen, Marcus Y.; Sun, Hong-Wei; Hasni, Sarfaraz; Mehta, Nehal N.

2018-01-01

BACKGROUND. Systemic lupus erythematosus (SLE) is associated with enhanced risk of atherosclerotic cardiovascular disease not explained by Framingham risk score (FRS). Immune dysregulation associated to a distinct subset of lupus proinflammatory neutrophils (low density granulocytes; LDGs) may play key roles in conferring enhanced CV risk. This study assessed if lupus LDGs are associated with in vivo vascular dysfunction and inflammation and coronary plaque. METHODS. SLE subjects and healthy controls underwent multimodal phenotyping of vascular disease by quantifying vascular inflammation (18F-fluorodeoxyglucose–PET/CT [18F-FDG–PET/CT]), arterial dysfunction (EndoPAT and cardio-ankle vascular index), and coronary plaque burden (coronary CT angiography). LDGs were quantified by flow cytometry. Cholesterol efflux capacity was measured in high-density lipoprotein–exposed (HDL-exposed) radioactively labeled cell lines. Whole blood RNA sequencing was performed to assess associations between transcriptomic profiles and vascular phenotype. RESULTS. Vascular inflammation, arterial stiffness, and noncalcified plaque burden (NCB) were increased in SLE compared with controls even after adjustment for traditional risk factors. In SLE, NCB directly associated with LDGs and associated negatively with cholesterol efflux capacity in fully adjusted models. A neutrophil gene signature reflective of the most upregulated genes in lupus LDGs associated with vascular inflammation and NCB. CONCLUSION. Individuals with SLE demonstrate vascular inflammation, arterial dysfunction, and NCB, which may explain the higher reported risk for acute coronary syndromes. The association of LDGs and neutrophil genes with vascular disease supports the hypothesis that distinct neutrophil subsets contribute to vascular damage and unstable coronary plaque in SLE. Results also support previous observations that neutrophils may disrupt HDL function and thereby promote atherogenesis. TRIAL REGISTRATION. Clinicaltrials.gov NCT00001372 FUNDING. Intramural Research Program NIAMS/NIH (ZIA AR041199) and Lupus Research Institute PMID:29669944

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

PubMed Central

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

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

PubMed

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

2014-12-01

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. Copyright © 2014 Elsevier Ltd. All rights reserved.

Structural and functional features of central nervous system lymphatics

PubMed Central

Louveau, Antoine; Smirnov, Igor; Keyes, Timothy J.; Eccles, Jacob D.; Rouhani, Sherin J.; Peske, J. David; Derecki, Noel C.; Castle, David; Mandell, James W.; Kevin, S. Lee; Harris, Tajie H.; Kipnis, Jonathan

2015-01-01

One of the characteristics of the CNS is the lack of a classical lymphatic drainage system. Although it is now accepted that the CNS undergoes constant immune surveillance that takes place within the meningeal compartment1–3, the mechanisms governing the entrance and exit of immune cells from the CNS remain poorly understood4–6. In searching for T cell gateways into and out of the meninges, we discovered functional lymphatic vessels lining the dural sinuses. These structures express all of the molecular hallmarks of lymphatic endothelial cells, are able to carry both fluid and immune cells from the CSF, and are connected to the deep cervical lymph nodes. The unique location of these vessels may have impeded their discovery to date, thereby contributing to the long-held concept of the absence of lymphatic vasculature in the CNS. The discovery of the CNS lymphatic system may call for a reassessment of basic assumptions in neuroimmunology and shed new light on the etiology of neuroinflammatory and neurodegenerative diseases associated with immune system dysfunction. PMID:26030524

Peripheral nervous system neuroimmunology seen by a neuro-pathologist.

PubMed

Vallat, J-M

2014-10-01

In most dysimmune neuropathies, historically the microscopical lesions were described prior to immunological studies. The latter along with neuropathological studies have found some immune, albeit incomplete, explanations of the mechanisms of these lesions which we will describe in two main syndromes: the primitive auto-immune inflammatory peripheral polyneuropathies (GBS and CIDP) and polyneuropathies induced by a monoclonal dysglobulinemia. In some patients who have to be discussed case by case pathology (nerve biopsy) will confirm the diagnosis, may help to delineate the molecular anomalies and identify lesional mechanisms. We will review the high variability of nerve lesions which is characteristic of dysimmune neuropathies. Pathological studies confirm that both humoral and cellular immune reactions against Schwann cell and/or axonal antigens are implicated in primitive dysimmune neuropathies due to a dysfunction or failure of immune tolerance mechanisms. In case of a polyneuropathy associated to a monoclonal dysglobulinemia, pathological and immunological studies have shown that in many patients, the dysglobulinemia did harm the peripheral nerve; knowledge of the pathological lesions and their mechanisms is of major interest for orienting specific treatments. Copyright © 2014. Published by Elsevier Masson SAS.

Clinical Aspects of the Control of Plasma Volume at Microgravity and During Return to One Gravity

NASA Technical Reports Server (NTRS)

Convertino, Victor A.

1995-01-01

Plasma volume is reduced by 10%-20% within 24 to 48 h of exposure to simulated or actual microgravity. The clinical importance of microgravity-induced hypovolemia is manifested by its relationship with orthostatic intolerance and reduced VO2max after return to one gravity (1G). Since there is no evidence to suggest plasma volume reduction during microgravity is associated with thirst or renal dysfunctions, a diuresis induced by an immediate blood volume shift to the central circulation appears responsible for microgravity-induced hypovolemia. Since most astronauts choose to restrict their fluid intake before a space mission, absence of increased urine output during actual spaceflight may be explained by low central venous pressure (CVP) which accompanies dehydration. Compelling evidence suggests that prolonged reduction in CVP during exposure to microgravity reflects a 'resetting' to a lower operating point which acts to limit plasma volume expansion during attempts to increase fluid intake. In groudbase and spaceflight experiments, successful restoration and maintenance of plasma volume prior to returning to an upright posture may depend upon development of treatments that can return CVP to its baseline 10 operating point. Fluid-loading and LBNP have not proved completely effective in restoring plasma volume, suggesting that they may not provide the stimulus to elevate the CVP operating point. On the other, exercise, which can chronically increase CVP, has been effective in expanding plasma volume when combined with adequate dietary intake of fluid and electrolytes. The success of designing experiments to understand the physiological mechanisms of and development of effective countermeasures for the control of plasma volume in microgravity and during return to one gravity will depend upon testing that can be conducted under standardized controlled baseline condi

Infectious and autoantibody-associated encephalitis: clinical features and long-term outcome.

PubMed

Pillai, Sekhar C; Hacohen, Yael; Tantsis, Esther; Prelog, Kristina; Merheb, Vera; Kesson, Alison; Barnes, Elizabeth; Gill, Deepak; Webster, Richard; Menezes, Manoj; Ardern-Holmes, Simone; Gupta, Sachin; Procopis, Peter; Troedson, Christopher; Antony, Jayne; Ouvrier, Robert A; Polfrit, Yann; Davies, Nicholas W S; Waters, Patrick; Lang, Bethan; Lim, Ming J; Brilot, Fabienne; Vincent, Angela; Dale, Russell C

2015-04-01

Pediatric encephalitis has a wide range of etiologies, clinical presentations, and outcomes. This study seeks to classify and characterize infectious, immune-mediated/autoantibody-associated and unknown forms of encephalitis, including relative frequencies, clinical and radiologic phenotypes, and long-term outcome. By using consensus definitions and a retrospective single-center cohort of 164 Australian children, we performed clinical and radiologic phenotyping blinded to etiology and outcomes, and we tested archived acute sera for autoantibodies to N-methyl-D-aspartate receptor, voltage-gated potassium channel complex, and other neuronal antigens. Through telephone interviews, we defined outcomes by using the Liverpool Outcome Score (for encephalitis). An infectious encephalitis occurred in 30%, infection-associated encephalopathy in 8%, immune-mediated/autoantibody-associated encephalitis in 34%, and unknown encephalitis in 28%. In descending order of frequency, the larger subgroups were acute disseminated encephalomyelitis (21%), enterovirus (12%), Mycoplasma pneumoniae (7%), N-methyl-D-aspartate receptor antibody (6%), herpes simplex virus (5%), and voltage-gated potassium channel complex antibody (4%). Movement disorders, psychiatric symptoms, agitation, speech dysfunction, cerebrospinal fluid oligoclonal bands, MRI limbic encephalitis, and clinical relapse were more common in patients with autoantibodies. An abnormal outcome occurred in 49% of patients after a median follow-up of 5.8 years. Herpes simplex virus and unknown forms had the worst outcomes. According to our multivariate analysis, an abnormal outcome was more common in patients with status epilepticus, magnetic resonance diffusion restriction, and ICU admission. We have defined clinical and radiologic phenotypes of infectious and immune-mediated/autoantibody-associated encephalitis. In this resource-rich cohort, immune-mediated/autoantibody-associated etiologies are common, and the recognition and treatment of these entities should be a clinical priority. Copyright © 2015 by the American Academy of Pediatrics.

Genotype, B-vitamin status, and androgens affect spaceflight-induced ophthalmic changes

PubMed Central

Zwart, Sara R.; Gregory, Jesse F.; Zeisel, Steven H.; Gibson, Charles R.; Mader, Thomas H.; Kinchen, Jason M.; Ueland, Per M.; Ploutz-Snyder, Robert; Heer, Martina A.; Smith, Scott M.

2016-01-01

Ophthalmic changes have occurred in a subset of astronauts on International Space Station missions. Visual deterioration is considered the greatest human health risk of spaceflight. Affected astronauts exhibit higher concentrations of 1-carbon metabolites (e.g., homocysteine) before flight. We hypothesized that genetic variations in 1-carbon metabolism genes contribute to susceptibility to ophthalmic changes in astronauts. We investigated 5 polymorphisms in the methionine synthase reductase (MTRR), methylenetetrahydrofolate reductase (MTHFR), serine hydroxymethyltransferase (SHMT), and cystathionine β-synthase (CBS) genes and their association with ophthalmic changes after flight in 49 astronauts. The number of G alleles of MTRR 66 and C alleles of SHMT1 1420 both contributed to the odds of visual disturbances. Preflight dehydroepiandrosterone was positively associated with cotton wool spots, and serum testosterone response during flight was associated with refractive change. Block regression showed that B-vitamin status and genetics were significant predictors of many of the ophthalmic outcomes that we observed. In one example, genetics trended toward improving (P = 0.10) and B-vitamin status significantly improved (P < 0.001) the predictive model for refractive change after flight. We document an association between MTRR 66 and SHMT1 1420 polymorphisms and spaceflight-induced vision changes. This line of research could lead to therapeutic options for both space travelers and terrestrial patients.—Zwart, S. R., Gregory, J. F., Zeisel, S. H., Gibson, C. R., Mader, T. H., Kinchen, J. M., Ueland, P. M., Ploutz-Snyder, R., Heer, M. A., Smith, S. M. Genotype, B-vitamin status, and androgens affect spaceflight-induced ophthalmic changes. PMID:26316272

Longitudinal characterization of dysfunctional T cell-activation during human acute Ebola infection

PubMed Central

Agrati, C; Castilletti, C; Casetti, R; Sacchi, A; Falasca, L; Turchi, F; Tumino, N; Bordoni, V; Cimini, E; Viola, D; Lalle, E; Bordi, L; Lanini, S; Martini, F; Nicastri, E; Petrosillo, N; Puro, V; Piacentini, M; Di Caro, A; Kobinger, G P; Zumla, A; Ippolito, G; Capobianchi, M R

2016-01-01

Data on immune responses during human Ebola virus disease (EVD) are scanty, due to limitations imposed by biosafety requirements and logistics. A sustained activation of T-cells was recently described but functional studies during the acute phase of human EVD are still missing. Aim of this work was to evaluate the kinetics and functionality of T-cell subsets, as well as the expression of activation, autophagy, apoptosis and exhaustion markers during the acute phase of EVD until recovery. Two EVD patients admitted to the Italian National Institute for Infectious Diseases, Lazzaro Spallanzani, were sampled sequentially from soon after symptom onset until recovery and analyzed by flow cytometry and ELISpot assay. An early and sustained decrease of CD4 T-cells was seen in both patients, with an inversion of the CD4/CD8 ratio that was reverted during the recovery period. In parallel with the CD4 T-cell depletion, a massive T-cell activation occurred and was associated with autophagic/apoptotic phenotype, enhanced expression of the exhaustion marker PD-1 and impaired IFN-gamma production. The immunological impairment was accompanied by EBV reactivation. The association of an early and sustained dysfunctional T-cell activation in parallel to an overall CD4 T-cell decline may represent a previously unknown critical point of Ebola virus (EBOV)-induced immune subversion. The recent observation of late occurrence of EBOV-associated neurological disease highlights the importance to monitor the immuno-competence recovery at discharge as a tool to evaluate the risk of late sequelae associated with resumption of EBOV replication. Further studies are required to define the molecular mechanisms of EVD-driven activation/exhaustion and depletion of T-cells. PMID:27031961

Longitudinal characterization of dysfunctional T cell-activation during human acute Ebola infection.

PubMed

Agrati, C; Castilletti, C; Casetti, R; Sacchi, A; Falasca, L; Turchi, F; Tumino, N; Bordoni, V; Cimini, E; Viola, D; Lalle, E; Bordi, L; Lanini, S; Martini, F; Nicastri, E; Petrosillo, N; Puro, V; Piacentini, M; Di Caro, A; Kobinger, G P; Zumla, A; Ippolito, G; Capobianchi, M R

2016-03-31

Data on immune responses during human Ebola virus disease (EVD) are scanty, due to limitations imposed by biosafety requirements and logistics. A sustained activation of T-cells was recently described but functional studies during the acute phase of human EVD are still missing. Aim of this work was to evaluate the kinetics and functionality of T-cell subsets, as well as the expression of activation, autophagy, apoptosis and exhaustion markers during the acute phase of EVD until recovery. Two EVD patients admitted to the Italian National Institute for Infectious Diseases, Lazzaro Spallanzani, were sampled sequentially from soon after symptom onset until recovery and analyzed by flow cytometry and ELISpot assay. An early and sustained decrease of CD4 T-cells was seen in both patients, with an inversion of the CD4/CD8 ratio that was reverted during the recovery period. In parallel with the CD4 T-cell depletion, a massive T-cell activation occurred and was associated with autophagic/apoptotic phenotype, enhanced expression of the exhaustion marker PD-1 and impaired IFN-gamma production. The immunological impairment was accompanied by EBV reactivation. The association of an early and sustained dysfunctional T-cell activation in parallel to an overall CD4 T-cell decline may represent a previously unknown critical point of Ebola virus (EBOV)-induced immune subversion. The recent observation of late occurrence of EBOV-associated neurological disease highlights the importance to monitor the immuno-competence recovery at discharge as a tool to evaluate the risk of late sequelae associated with resumption of EBOV replication. Further studies are required to define the molecular mechanisms of EVD-driven activation/exhaustion and depletion of T-cells.

Effects of Weightlessness on Human Fluid and Electrolyte Physiology

NASA Technical Reports Server (NTRS)

Leach, Carolyn S.; Johnson, Philip C., Jr.

1991-01-01

The changes that occur in human fluid and electrolyte physiology during the acute and adaptive phases of adaptation to spaceflight are summarized. A number of questions remain to be answered. At a time when plasma volume and extracellular fluid volume are contracted and salt and water intake is unrestricted. ADH does not correct the volume deficit and serum sodium decreases. Change in secretion or activity of a natriuretic factor during spaceflight is one possible explanation. Recent identification of a polypeptide hormone produced in cardiac muscle cells which is natiuretic, is hypotensive, and has an inhibitory effect on renin and aldosterone secretion has renewed interest in the role of a natriuretic factor. The role of this atrial natriuretic factor (ANF) in both long- and short-term variation in extracellular volumes and in the inability of the kidney to bring about an escape from the sodium-retaining state accompanying chronic cardiac dysfunction makes it reasonable to look for a role of ANF in the regulation of sodium during exposure to microgravity. Prostaglandin-E is another hormone that may antagonize the action of ADH. Assays of these hormones will be performed on samples from crew members in the future.

Endocrine and metabolic disorders associated with human immune deficiency virus infection.

PubMed

Unachukwu, C N; Uchenna, D I; Young, E E

2009-01-01

Many reports have described endocrine and metabolic disorders in the human immunodeficiency virus (HIV) infection. This article reviewed various reports in the literature in order to increase the awareness and thus the need for early intervention when necessary. Data were obtained from MEDLINE, Google search and otherjournals on 'HIV, Endocrinopathies/Metabolic Disorders' from 1985 till 2007. Studies related to HIV associated endocrinopathies and metabolic disorders in the last two decades were reviewed. Information on epidemiology, pathogenesis, diagnosis and treatment of the target organ endocrinopathies and metabolic disorders in HIV/AIDS were extracted from relevant literature. Endocrine and metabolic disturbances occur in the course of HIV infection. Pathogenesis includes direct infection of endocrine glands by HIV or opportunistic organisms, infiltration by neoplasms and side effects of drugs. Adrenal insufficiency is the commonest HIV endocrinopathy with cytomegalovirus adrenalitis occurring in 40-88% of cases. Thyroid dysfunction may occur as euthyroid sick syndrome or sub-clinical hypothyroidism. Hypogonadotrophic dysfunction accounts for 75% of HIV-associated hypogonadism, with prolonged amenorrhoea being three times more likely in the women. Pancreatic dysfunction may result in hypoglycaemia or diabetes mellitus (DM). Highly active antiretroviral therapy (HAART) especially protease inhibitors has been noted to result in insulin resistance and lipodystrophy. Virtually every endocrine organ is involved in the course of HIV infection. Detailed endocrinological and metabolic evaluation and appropriate treatment is necessary in the optimal management of patients with HIV infection in our environment.

Prevalence and Predictors of Thyroid Dysfunction in Patients with HIV Infection and Acquired Immunodeficiency Syndrome: An Indian Perspective.

PubMed

Sharma, Neera; Sharma, Lokesh Kumar; Dutta, Deep; Gadpayle, Adesh Kisanji; Anand, Atul; Gaurav, Kumar; Mukherjee, Sabyasachi; Bansal, Rahul

2015-01-01

Background. Predictors of thyroid dysfunction in HIV are not well determined. This study aimed to determine the prevalence and predictors of thyroid dysfunction in HIV infected Indians. Methods. Consecutive HIV patients, 18-70 years of age, without any severe comorbid state, having at least 1-year follow-up at the antiretroviral therapy clinic, underwent clinical assessment and hormone assays. Results. From initially screened 527 patients, 359 patients (61.44 ± 39.42 months' disease duration), having good immune function [CD4 count >200 cell/mm(3): 90.25%; highly active antiretroviral therapy (HAART): 88.58%], were analyzed. Subclinical hypothyroidism (ScH) was the commonest thyroid dysfunction (14.76%) followed by sick euthyroid syndrome (SES) (5.29%) and isolated low TSH (3.1%). Anti-TPO antibody (TPOAb) was positive in 3.90%. Baseline CD4 count had inverse correlation with TPOAb after adjusting for age and body mass index. Stepwise linear regression revealed baseline CD4 count, TPOAb, and tuberculosis to be best predictors of ScH after adjusting for age, weight, duration of HIV, and history of opportunistic fungal and viral infections. Conclusion. Burden of thyroid dysfunction in chronic HIV infection with stable immune function is lower compared to pre-HAART era. Thyroid dysfunction is primarily of nonautoimmune origin, predominantly ScH. Severe immunodeficiency at disease onset, TPOAb positivity, and tuberculosis were best predictors of ScH.

RNA-Binding Proteins in Female Reproductive Pathologies.

PubMed

Khalaj, Kasra; Miller, Jessica E; Fenn, Christian R; Ahn, SooHyun; Luna, Rayana L; Symons, Lindsey; Monsanto, Stephany P; Koti, Madhuri; Tayade, Chandrakant

2017-06-01

RNA-binding proteins are key regulatory molecules involved primarily in post-transcriptional gene regulation of RNAs. Post-transcriptional gene regulation is critical for adequate cellular growth and survival. Recent reports have shown key interactions between these RNA-binding proteins and other regulatory elements, such as miRNAs and long noncoding RNAs, either enhancing or diminishing their response to RNA stabilization. Many RNA-binding proteins have been reported to play a functional role in mediation of cytokines involved in inflammation and immune dysfunction, and some have been classified as global post-transcriptional regulators of inflammation. The ubiquitous expression of RNA-binding proteins in a wide variety of cell types and their unique mechanisms of degradative action provide evidence that they are involved in reproductive tract pathologies. Aberrant inflammation and immune dysfunction are major contributors to the pathogenesis and disease pathophysiology of many reproductive pathologies, including ovarian and endometrial cancers in the female reproductive tract. Herein, we discuss various RNA-binding proteins and their unique contributions to female reproductive pathologies with a focus on those mediated by aberrant inflammation and immune dysfunction. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Ablating the aryl hydrocarbon receptor (AhR) in CD11c+ cells perturbs intestinal epithelium development and intestinal immunity.

PubMed

Chng, Song Hui; Kundu, Parag; Dominguez-Brauer, Carmen; Teo, Wei Ling; Kawajiri, Kaname; Fujii-Kuriyama, Yoshiaki; Mak, Tak Wah; Pettersson, Sven

2016-04-12

Diet and microbiome derived indole derivatives are known to activate the ligand induced transcription factor, the Aryl hydrocarbon Receptor (AhR). While the current understanding of AhR biology has confirmed its role in mucosal lymphocytes, its function in intestinal antigen presenting cells (APCs) is poorly understood. Here, we report that Cre-mediated deletion of AhR in CD11c-expressing cells in C57/BL6 mice is associated with altered intestinal epithelial morphogenesis in vivo. Moreover, when co-cultured with AhR-deficient DCs ex vivo, intestinal organoids showed reduced SRY (sex determining region Y)-box 9 and increased Mucin 2 expression, which correlates with reduced Paneth cells and increased goblet cell differentiation, similar to the data obtained in vivo. Further, characterization of intestinal APC subsets, devoid of AhR, revealed an expression pattern associated with aberrant intrinsic Wnt pathway regulation. At a functional level, the loss of AhR in APCs resulted in a dysfunctional epithelial barrier, associated with a more aggressive chemically induced colitis compared to wild type animals. Our results are consistent with a model whereby the AhR signalling pathway may participate in the regulation of innate immunity through intestinal epithelium development and mucosal immunity.

Project Mercury: NASA's first manned space programme

NASA Astrophysics Data System (ADS)

Catchpole, John

Project Mercury will offer a developmental resume of the first American manned spaceflight programme and its associated infrastructure, including accounts of space launch vehicles. The book highlights the differences in Redstone/Atlas technology, drawing similar comparisons between ballistic capsules and alternative types of spacecraft. The book also covers astronaut selection and training, as well as tracking systems, flight control, basic principles of spaceflight and detailed accounts of individual flights.

Spaceflight Did Not Impair Cardiovascular Responses to Upright Posture in an Elderly Astronaut

NASA Technical Reports Server (NTRS)

Rossum, Alfred C.; Ziegler, Michael G.; Meck, Janice V.

2001-01-01

Some of the cardiovascular changes associated with spaceflight have similarities to those associated with aging. We studied the neuroendocrine and hemodynamic responses to upright posture in a 77 year old astronaut before and after spaceflight and compared them to those of a group of 20 younger (41 plus or minus 1 years) astronauts. While arterial pressure responses to standing were similar between the young and old astronauts, hemodynamic profiles were quite different. The elderly astronaut achieved adequate standing arterial pressure primarily by maintaining stroke volume and thus cardiac output. In spite of very high norepinephrine release, he had very little increase in heart rate or total peripheral resistance. This pattern persisted on all test occasions. These responses suggest high sympathetic responses, down-regulated adrenergic receptors and decreased venous compliance typical of aging. In contrast, younger astronauts did not maintain stroke volume or cardiac output with standing, but had significant increases in heart rate and resistance. These results suggest that this elderly subject had cardiovascular responses to standing that are expected in an aged person. These responses were not deleteriously affected by spaceflight. We suggest that healthy, fit elderly individuals are able to withstand the stresses of extreme environments and are not necessarily limited in their activities simply due to their chronological age.

Polycyclic aromatic hydrocarbons, tobacco smoke, and epigenetic remodeling in asthma

PubMed Central

Klingbeil, E. C.; Hew, K. M.; Nygaard, U. C.; Nadeau, K. C.

2014-01-01

Environmental determinants including aerosolized pollutants such as polycyclic aromatic hydrocarbons (PAHs) and tobacco smoke have been associated with exacerbation and increased incidence of asthma. The influence of aerosolized pollutants on the development of immune dysfunction in asthmatics has been suggested to be mediated through epigenetic remodeling. Genome accessibility and transcription are regulated primarily through DNA methylation, histone modification, and microRNA transcript silencing. Epigenetic remodeling has been shown in studies to be associated with Th2 polarization and associated cytokine and chemokine regulation in the development of asthma. This review will present evidence for the contribution of the aerosolized pollutants PAH and environmental tobacco smoke to epigenetic remodeling in asthma. PMID:24760221

Effects and Responses to Spaceflight in the Mouse Retina

NASA Technical Reports Server (NTRS)

Zanello, Susana B.; Theriot, Corey; Westby, Christian; Boyle, Richard

2011-01-01

Several stress environmental factors are combined in a unique fashion during spaceflight, affecting living beings widely across their physiological systems. Recently, attention has been placed on vision changes in astronauts returning from long duration missions. Alterations include hyperoptic shift, globe flattening, choroidal folds and optic disc edema, which are probably associated with increased intracranial pressure. These observations justify a better characterization of the ocular health risks associated with spaceflight. This study investigates the impact of spaceflight on the biology of the mouse retina. Within a successful tissue sharing effort, eyes from albino Balb/cJ mice aboard STS-133 were collected for histological analysis and gene expression profiling of the retina at 1 and 7 days after landing. Both vivarium and AEM (Animal Enclosure Module) mice were used as ground controls. Oxidative stress-induced DNA damage was higher in the flight samples compared to controls on R+1, and decreased on R+7. A trend toward higher oxidative and cellular stress response gene expression was also observed on R+1 compared to AEM controls, and these levels decreased on R+7. Several genes coding for key antioxidant enzymes, namely, heme-oxygenase-1, peroxiredoxin, and catalase, were among those upregulated after flight. Likewise, NF B and TGFbeta1, were upregulated in one flight specimen that overall showed the most elevated oxidative stress markers on R+1. In addition, retinas from vivarium control mice evidenced higher oxidative stress markers, NF B and TGFbeta1, likely due to the more intense illumination in vivarium cages versus the AEM. These preliminary data suggest that spaceflight represents a source of environmental stress that translates into oxidative and cellular stress in the retina, which is partially reversible upon return to Earth. Further work is needed to dissect the contribution of the various spaceflight factors (microgravity, radiation) and to evaluate the impact of the stress response on retinal health.

Falls and Fall-Prevention in Older Persons: Geriatrics Meets Spaceflight!

PubMed Central

Goswami, Nandu

2017-01-01

This paper provides a general overview of key physiological consequences of microgravity experienced during spaceflight and of important parallels and connections to the physiology of aging. Microgravity during spaceflight influences cardiovascular function, cerebral autoregulation, musculoskeletal, and sensorimotor system performance. A great deal of research has been carried out to understand these influences and to provide countermeasures to reduce the observed negative consequences of microgravity on physiological function. Such research can inform and be informed by research related to physiological changes and the deterioration of physiological function due to aging. For example, head-down bedrest is used as a model to study effects of spaceflight deconditioning due to reduced gravity. As hospitalized older persons spend up to 80% of their time in bed, the deconditioning effects of bedrest confinement on physiological functions and parallels with spaceflight deconditioning can be exploited to understand and combat both variations of deconditioning. Deconditioning due to bed confinement in older persons can contribute to a downward spiral of increasing frailty, orthostatic intolerance, falls, and fall-related injury. As astronauts in space spend substantial amounts of time carrying out exercise training to counteract the microgravity-induced deconditioning and to counteract orthostatic intolerance on return to Earth, it is logical to suggest some of these interventions for bed-confined older persons. Synthesizing knowledge regarding deconditioning due to reduced gravitational stress in space and deconditioning during bed confinement allows for a more comprehensive approach that can incorporate aspects such as (mal-) nutrition, muscle strength and function, cardiovascular (de-) conditioning, and cardio-postural interactions. The impact of such integration can provide new insights and lead to methods of value for both space medicine and geriatrics (Geriatrics meets spaceflight!). In particular, such integration can lead to procedures that address the morbidity and the mortality associated with bedrest immobilization and in the rising health care costs associated with an aging population demographic. PMID:29075195

The Effects of Training on Anxiety and Task Performance in Simulated Suborbital Spaceflight.

PubMed

Blue, Rebecca S; Bonato, Frederick; Seaton, Kimberly; Bubka, Andrea; Vardiman, Johnené L; Mathers, Charles; Castleberry, Tarah L; Vanderploeg, James M

2017-07-01

In commercial spaceflight, anxiety could become mission-impacting, causing negative experiences or endangering the flight itself. We studied layperson response to four varied-length training programs (ranging from 1 h-2 d of preparation) prior to centrifuge simulation of launch and re-entry acceleration profiles expected during suborbital spaceflight. We examined subject task execution, evaluating performance in high-stress conditions. We sought to identify any trends in demographics, hemodynamics, or similar factors in subjects with the highest anxiety or poorest tolerance of the experience. Volunteers participated in one of four centrifuge training programs of varied complexity and duration, culminating in two simulated suborbital spaceflights. At most, subjects underwent seven centrifuge runs over 2 d, including two +Gz runs (peak +3.5 Gz, Run 2) and two +Gx runs (peak +6.0 Gx, Run 4) followed by three runs approximating suborbital spaceflight profiles (combined +Gx and +Gz, peak +6.0 Gx and +4.0 Gz). Two cohorts also received dedicated anxiety-mitigation training. Subjects were evaluated on their performance on various tasks, including a simulated emergency. Participating in 2-7 centrifuge exposures were 148 subjects (105 men, 43 women, age range 19-72 yr, mean 39.4 ± 13.2 yr, body mass index range 17.3-38.1, mean 25.1 ± 3.7). There were 10 subjects who withdrew or limited their G exposure; history of motion sickness was associated with opting out. Shorter length training programs were associated with elevated hemodynamic responses. Single-directional G training did not significantly improve tolerance. Training programs appear best when high fidelity and sequential exposures may improve tolerance of physical/psychological flight stressors. The studied variables did not predict anxiety-related responses to these centrifuge profiles.Blue RS, Bonato F, Seaton K, Bubka A, Vardiman JL, Mathers C, Castleberry TL, Vanderploeg JM. The effects of training on anxiety and task performance in simulated suborbital spaceflight. Aerosp Med Hum Perform. 2017; 88(7):641-650.

Falls and Fall-Prevention in Older Persons: Geriatrics Meets Spaceflight!

PubMed

Goswami, Nandu

2017-01-01

This paper provides a general overview of key physiological consequences of microgravity experienced during spaceflight and of important parallels and connections to the physiology of aging. Microgravity during spaceflight influences cardiovascular function, cerebral autoregulation, musculoskeletal, and sensorimotor system performance. A great deal of research has been carried out to understand these influences and to provide countermeasures to reduce the observed negative consequences of microgravity on physiological function. Such research can inform and be informed by research related to physiological changes and the deterioration of physiological function due to aging. For example, head-down bedrest is used as a model to study effects of spaceflight deconditioning due to reduced gravity. As hospitalized older persons spend up to 80% of their time in bed, the deconditioning effects of bedrest confinement on physiological functions and parallels with spaceflight deconditioning can be exploited to understand and combat both variations of deconditioning. Deconditioning due to bed confinement in older persons can contribute to a downward spiral of increasing frailty, orthostatic intolerance, falls, and fall-related injury. As astronauts in space spend substantial amounts of time carrying out exercise training to counteract the microgravity-induced deconditioning and to counteract orthostatic intolerance on return to Earth, it is logical to suggest some of these interventions for bed-confined older persons. Synthesizing knowledge regarding deconditioning due to reduced gravitational stress in space and deconditioning during bed confinement allows for a more comprehensive approach that can incorporate aspects such as (mal-) nutrition, muscle strength and function, cardiovascular (de-) conditioning, and cardio-postural interactions. The impact of such integration can provide new insights and lead to methods of value for both space medicine and geriatrics (Geriatrics meets spaceflight!). In particular, such integration can lead to procedures that address the morbidity and the mortality associated with bedrest immobilization and in the rising health care costs associated with an aging population demographic.

Malnutrition and vaccination in developing countries

PubMed Central

Prendergast, Andrew J.

2015-01-01

Malnutrition contributes to an estimated 45% of deaths among children under 5 years of age in developing countries, predominantly due to infections. Malnourished children therefore stand to benefit hugely from vaccination, but malnutrition has been described as the most common immunodeficiency globally, suggesting that they may not be able to respond effectively to vaccines. The immunology of malnutrition remains poorly characterized, but is associated with impairments in mucosal barrier integrity, and innate and adaptive immune dysfunction. Despite this, the majority of malnourished children can mount a protective immune response following vaccination, although the timing, quality and duration of responses may be impaired. This paper reviews the evidence for vaccine immunogenicity in malnourished children, discusses the importance of vaccination in prevention of malnutrition and highlights evidence gaps in our current knowledge. PMID:25964453

Influenza vaccine response profiles are affected by vaccine preparation and preexisting immunity, but not HIV infection.

PubMed

Berger, Christoph T; Greiff, Victor; Mehling, Matthias; Fritz, Stefanie; Meier, Marc A; Hoenger, Gideon; Conen, Anna; Recher, Mike; Battegay, Manuel; Reddy, Sai T; Hess, Christoph

2015-01-01

Vaccines dramatically reduce infection-related morbidity and mortality. Determining factors that modulate the host response is key to rational vaccine design and demands unsupervised analysis. To longitudinally resolve influenza-specific humoral immune response dynamics we constructed vaccine response profiles of influenza A- and B-specific IgM and IgG levels from 42 healthy and 31 HIV infected influenza-vaccinated individuals. Pre-vaccination antibody levels and levels at 3 predefined time points after vaccination were included in each profile. We performed hierarchical clustering on these profiles to study the extent to which HIV infection associated immune dysfunction, adaptive immune factors (pre-existing influenza-specific antibodies, T cell responses), an innate immune factor (Mannose Binding Lectin, MBL), demographic characteristics (gender, age), or the vaccine preparation (split vs. virosomal) impacted the immune response to influenza vaccination. Hierarchical clustering associated vaccine preparation and pre-existing IgG levels with the profiles of healthy individuals. In contrast to previous in vitro and animal data, MBL levels had no impact on the adaptive vaccine response. Importantly, while HIV infected subjects with low CD4 T cell counts showed a reduced magnitude of their vaccine response, their response profiles were indistinguishable from those of healthy controls, suggesting quantitative but not qualitative deficits. Unsupervised profile-based analysis ranks factors impacting the vaccine-response by relative importance, with substantial implications for comparing, designing and improving vaccine preparations and strategies. Profile similarity between HIV infected and HIV negative individuals suggests merely quantitative differences in the vaccine response in these individuals, offering a rationale for boosting strategies in the HIV infected population.

Iso-risk air no decompression limits after scoring marginal decompression sickness cases as non-events.

PubMed

Murphy, F Gregory; Swingler, Ashleigh J; Gerth, Wayne A; Howle, Laurens E

2018-01-01

Decompression sickness (DCS) in humans is associated with reductions in ambient pressure that occur during diving, aviation, or certain manned spaceflight operations. Its signs and symptoms can include, but are not limited to, joint pain, radiating abdominal pain, paresthesia, dyspnea, general malaise, cognitive dysfunction, cardiopulmonary dysfunction, and death. Probabilistic models of DCS allow the probability of DCS incidence and time of occurrence during or after a given hyperbaric or hypobaric exposure to be predicted based on how the gas contents or gas bubble volumes vary in hypothetical tissue compartments during the exposure. These models are calibrated using data containing the pressure and respired gas histories of actual exposures, some of which resulted in DCS, some of which did not, and others in which the diagnosis of DCS was not clear. The latter are referred to as marginal DCS cases. In earlier works, a marginal DCS event was typically weighted as 0.1, with a full DCS event being weighted as 1.0, and a non-event being weighted as 0.0. Recent work has shown that marginal DCS events should be weighted as 0.0 when calibrating gas content models. We confirm this indication in the present work by showing that such models have improved performance when calibrated to data with marginal DCS events coded as non-events. Further, we investigate the ramifications of derating marginal events on model-prescribed air diving no-stop limits. Copyright © 2017 Elsevier Ltd. All rights reserved.

In vivo detection of clinically non-apparent ocular surface inflammation in patients with meibomian gland dysfunction-associated refractory dry eye symptoms: a pilot study

PubMed Central

Qazi, Y; Kheirkhah, A; Blackie, C; Cruzat, A; Trinidad, M; Williams, C; Korb, D R; Hamrah, P

2015-01-01

Purpose The utility of in vivo confocal microscopy (IVCM) in the investigation of palpebral conjunctival and corneal inflammation in patients with meibomian gland dysfunction (MGD)-associated refractory dry eye symptoms following gland expression, despite objective clinical improvement. Methods A retrospective, observational pilot study was conducted evaluating five patients with MGD-associated refractory dry eye symptoms and three control groups: symptomatic untreated MGD patients (n=3), treatment-responsive MGD patients with improved symptoms (n=3) and asymptomatic healthy normals (n=11). Ocular surface disease index (OSDI) scores, tear break-up time (TBUT), the number of meibomian glands yielding liquid secretion (MGYLS), palpebral conjunctival epithelial and substantia propria immune cell (EIC, SIC), and corneal dendritic cell (DC) densities were measured. Results Despite clinical improvement (TBUT: 6.4±1.2 s to 10.1±2.1 s, P=0.03; MGYLS: 3.5±0.8 glands to 7.0±1.1 glands, P=0.13) and a normal clinical examination post treatment, MGD patients remained symptomatic. IVCM revealed increased immune cells in the palpebral conjunctiva (refractory MGD EIC=592.6±110.1 cells/mm2; untreated MGD EIC=522.6±104.7 cells/mm2, P=0.69; responsive MGD EIC=194.9±119.4 cells/mm2, P<0.01; normals EIC=123.7±19.2 cells/mm2, P< 0.001), but not the cornea (refractory MGD DC=60.9±28.3 cells/mm2; normals DC=25.9±6.3 cells/mm2; P=0.43). EIC did not correlate with TBUT (Rs=−0.26, P=0.33). OSDI scores correlated with both EIC (Rs=0.76, P<0.001) and TBUT (Rs=−0.69, P<0.01) but not SIC. Intraglandular immune cells were also seen. Conclusion MGD-associated refractory symptoms and the symptom-sign disparity may be explained by clinically non-apparent, active inflammation of the palpebral conjunctiva as detected by IVCM. These patients may benefit from anti-inflammatory therapy. PMID:26088680

Autonomic and inflammatory consequences of posttraumatic stress disorder and the link to cardiovascular disease.

PubMed

Brudey, Chevelle; Park, Jeanie; Wiaderkiewicz, Jan; Kobayashi, Ihori; Mellman, Thomas A; Marvar, Paul J

2015-08-15

Stress- and anxiety-related disorders are on the rise in both military and general populations. Over the next decade, it is predicted that treatment of these conditions, in particular, posttraumatic stress disorder (PTSD), along with its associated long-term comorbidities, will challenge the health care system. Multiple organ systems are adversely affected by PTSD, and PTSD is linked to cancer, arthritis, digestive disease, and cardiovascular disease. Evidence for a strong link between PTSD and cardiovascular disease is compelling, and this review describes current clinical data linking PTSD to cardiovascular disease, via inflammation, autonomic dysfunction, and the renin-angiotensin system. Recent clinical and preclinical evidence regarding the role of the renin-angiotensin system in the extinction of fear memory and relevance in PTSD-related immune and autonomic dysfunction is also addressed. Copyright © 2015 the American Physiological Society.

HIV and neurocognitive dysfunction.

PubMed

Spudich, Serena

2013-09-01

The spectrum of HIV-associated neurocognitive disorder (HAND) has been dramatically altered in the setting of widely available effective antiretroviral therapy (ART). Once culminating in dementia in many individuals infected with HIV, HAND now typically manifests as more subtle, though still morbid, forms of cognitive impairment in persons surviving long-term with treated HIV infection. Despite the substantial improvement in severity of this disorder, the fact that neurologic injury persists despite ART remains a challenge to the community of patients, providers and investigators aiming to optimize quality of life for those living with HIV. Cognitive dysfunction in treated HIV may reflect early irreversible CNS injury accrued before ART is typically initiated, ongoing low-level CNS infection and progressive injury in the setting of ART, or comborbidities including effects of treatment which may confound the beneficial reduction in viral replication and immune activation effected by ART.

A holistic approach to factors affecting depression in haemodialysis patients.

PubMed

Gerogianni, Georgia; Kouzoupis, Anastasios; Grapsa, Eirini

2018-05-19

Depression in dialysis populations is affected by co-morbid diseases, such as cardiovascular disease, diabetes, and immune dysfunction, and it also includes high suicide risk and frequent hospitalizations. Depressive disorders have a close association with malnutrition and chronic inflammation, as well as with cognitive impairment. Impaired cognitive function may be manifested as low adherence to dialysis treatment, leading to malnutrition. Additionally, chronic pain and low quality of sleep lead to high rates of depressive symptoms in haemodialysis patients, while an untreated depression can cause sleep disturbances and increased mortality risk. Depression can also lead to sexual dysfunction and non-adherence, while unemployment can cause depressive disorders, due to patients' feelings of being a financial burden on their family. The present review provides a holistic approach to the factors affecting depression in haemodialysis, offering significant knowledge to renal professionals.

Gut microbial translocation corrupts myeloid cell function to control bacterial infection during liver cirrhosis.

PubMed

Hackstein, Carl-Philipp; Assmus, Lisa Mareike; Welz, Meike; Klein, Sabine; Schwandt, Timo; Schultze, Joachim; Förster, Irmgard; Gondorf, Fabian; Beyer, Marc; Kroy, Daniela; Kurts, Christian; Trebicka, Jonel; Kastenmüller, Wolfgang; Knolle, Percy A; Abdullah, Zeinab

2017-03-01

Patients with liver cirrhosis suffer from increased susceptibility to life-threatening bacterial infections that cause substantial morbidity. Experimental liver fibrosis in mice induced by bile duct ligation or CCl 4 application was used to characterise the mechanisms determining failure of innate immunity to control bacterial infections. In murine liver fibrosis, translocation of gut microbiota induced tonic type I interferon (IFN) expression in the liver. Such tonic IFN expression conditioned liver myeloid cells to produce high concentrations of IFN upon intracellular infection with Listeria that activate cytosolic pattern recognition receptors. Such IFN-receptor signalling caused myeloid cell interleukin (IL)-10 production that corrupted antibacterial immunity, leading to loss of infection-control and to infection-associated mortality. In patients with liver cirrhosis, we also found a prominent liver IFN signature and myeloid cells showed increased IL-10 production after bacterial infection. Thus, myeloid cells are both source and target of IFN-induced and IL-10-mediated immune dysfunction. Antibody-mediated blockade of IFN-receptor or IL-10-receptor signalling reconstituted antibacterial immunity and prevented infection-associated mortality in mice with liver fibrosis. In severe liver fibrosis and cirrhosis, failure to control bacterial infection is caused by augmented IFN and IL-10 expression that incapacitates antibacterial immunity of myeloid cells. Targeted interference with the immune regulatory host factors IL-10 and IFN reconstitutes antibacterial immunity and may be used as therapeutic strategy to control bacterial infections in patients with liver cirrhosis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Burn-injury affects gut-associated lymphoid tissues derived CD4+ T cells.

PubMed

Fazal, Nadeem; Shelip, Alla; Alzahrani, Alhusain J

2013-01-01

After scald burn-injury, the intestinal immune system responds to maintain immune balance. In this regard CD4+T cells in Gut-Associated Lymphoid Tissues (GALT), like mesenteric lymph nodes (MLN) and Peyer's patches (PP) respond to avoid immune suppression following major injury such as burn. Therefore, we hypothesized that the gut CD4+T cells become dysfunctional and turn the immune homeostasis towards depression of CD4+ T cell-mediated adaptive immune responses. In the current study we show down regulation of mucosal CD4+ T cell proliferation, IL-2 production and cell surface marker expression of mucosal CD4+ T cells moving towards suppressive-type. Acute burn-injury lead to up-regulation of regulatory marker (CD25+), down regulation of adhesion (CD62L, CD11a) and homing receptor (CD49d) expression, and up-regulation of negative co-stimulatory (CTLA-4) molecule. Moreover, CD4+CD25+ T cells of intestinal origin showed resistance to spontaneous as well as induced apoptosis that may contribute to suppression of effector CD4+ T cells. Furthermore, gut CD4+CD25+ T cells obtained from burn-injured animals were able to down-regulate naïve CD4+ T cell proliferation following adoptive transfer of burn-injured CD4+CD25+ T cells into sham control animals, without any significant effect on cell surface activation markers. Together, these data demonstrate that the intestinal CD4+ T cells evolve a strategy to promote suppressive CD4+ T cell effector responses, as evidenced by enhanced CD4+CD25+ T cells, up-regulated CTLA-4 expression, reduced IL-2 production, tendency towards diminished apoptosis of suppressive CD4+ T cells, and thus lose their natural ability to regulate immune homeostasis following acute burn-injury and prevent immune paralysis.

Unusual association of amyotrophic lateral sclerosis and myasthenia gravis: A dysregulation of the adaptive immune system?

PubMed

Del Mar Amador, Maria; Vandenberghe, Nadia; Berhoune, Nawel; Camdessanché, Jean-Philippe; Gronier, Sophie; Delmont, Emilien; Desnuelle, Claude; Cintas, Pascal; Pittion, Sophie; Louis, Sarah; Demeret, Sophie; Lenglet, Timothée; Meininger, Vincent; Salachas, François; Pradat, Pierre-François; Bruneteau, Gaëlle

2016-06-01

Myasthenia gravis is an autoimmune disorder affecting neuromuscular junctions that has been associated with a small increased risk of amyotrophic lateral sclerosis (ALS). Here, we describe a retrospective series of seven cases with a concomitant diagnosis of ALS and myasthenia gravis, collected among the 18 French reference centers for ALS in a twelve year period. After careful review, only six patients strictly met the diagnostic criteria for both ALS and myasthenia gravis. In these patients, limb onset of ALS was reported in five (83%) cases. Localization of myasthenia gravis initial symptoms was ocular in three (50%) cases, generalized in two (33%) and bulbar in one (17%). Median delay between onset of the two conditions was 19 months (6-319 months). Anti-acetylcholine receptor antibodies testing was positive in all cases. All patients were treated with riluzole and one had an associated immune-mediated disease. In the one last ALS case, the final diagnosis was false-positivity for anti-acetylcholine receptor antibodies. The co-occurrence of ALS and myasthenia gravis is rare and requires strict diagnostic criteria. Its demonstration needs thoughtful interpretation of electrophysiological results and exclusion of false positivity for myasthenia gravis antibody testing in some ALS cases. This association may be triggered by a dysfunction of adaptive immunity. Copyright © 2016 Elsevier B.V. All rights reserved.

Microbiological concerns and methodological approaches related to bacterial water quality in spaceflight

NASA Technical Reports Server (NTRS)

Pyle, Barry H.; Mcfeters, Gordon A.

1992-01-01

A number of microbiological issues are of critical importance to crew health and system performance in spacecraft water systems. This presentation reviews an army of these concerns which include factors that influence water treatment and disinfection in spaceflight such as biofilm formation and the physiological responses of bacteria in clean water systems. Factors associated with spaceflight like aerosol formation under conditions of microgravity are also discussed within the context of airborne infections such as Legionellosis. Finally, a spectrum of analytical approaches is reviewed to provide an evaluation of methodological alternatives that have been suggested or used to detect microorganisms of interest in water systems. These range from classical approaches employing colony formation on specific microbiological growth media to direct (i.e. microscopic) and indirect (e.g. electrochemical) methods as well as the use of molecular approaches and gene probes. These techniques are critically evaluated for their potential utility in determining microbiological water quality through the detection of microorganisms under the influence of ambient environmental stress inherent in spaceflight water systems.

KENNEDY SPACE CENTER, FLA. - Valerie Cassanto, with Instrumentation Technology Associates, Inc., works on an experiment found during the search for Columbia debris. Included in the Commercial ITA Biomedical Experiments payload on mission STS-107 are urokinase cancer research, microencapsulation of drugs, the Growth of Bacterial Biofilm on Surfaces during Spaceflight (GOBBSS), and tin crystal formation.

NASA Image and Video Library

2003-05-06

KENNEDY SPACE CENTER, FLA. - Valerie Cassanto, with Instrumentation Technology Associates, Inc., works on an experiment found during the search for Columbia debris. Included in the Commercial ITA Biomedical Experiments payload on mission STS-107 are urokinase cancer research, microencapsulation of drugs, the Growth of Bacterial Biofilm on Surfaces during Spaceflight (GOBBSS), and tin crystal formation.

Interplay among gut microbiota, intestinal mucosal barrier and enteric neuro-immune system: a common path to neurodegenerative diseases?

PubMed

Pellegrini, Carolina; Antonioli, Luca; Colucci, Rocchina; Blandizzi, Corrado; Fornai, Matteo

2018-05-24

Neurological diseases, such as Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis (ALS) and multiple sclerosis, are often associated with functional gastrointestinal disorders. These gastrointestinal disturbances may occur at all stages of the neurodegenerative diseases, to such an extent that they are now considered an integral part of their clinical picture. Several lines of evidence support the contention that, in central neurodegenerative diseases, changes in gut microbiota and enteric neuro-immune system alterations could contribute to gastrointesinal dysfunctions as well as initiation and upward spreading of the neurologic disorder. The present review has been intended to provide a comprehensive overview of the available knowledge on the role played by enteric microbiota, mucosal immune system and enteric nervous system, considered as an integrated network, in the pathophysiology of the main neurological diseases known to be associated with intestinal disturbances. In addition, based on current human and pre-clinical evidence, our intent was to critically discuss whether changes in the dynamic interplay between gut microbiota, intestinal epithelial barrier and enteric neuro-immune system are a consequence of the central neurodegeneration or might represent the starting point of the neurodegenerative process. Special attention has been paid also to discuss whether alterations of the enteric bacterial-neuro-immune network could represent a common path driving the onset of the main neurodegenerative diseases, even though each disease displays its own distinct clinical features.

Frailty and sarcopenia: The potential role of an aged immune system.

PubMed

Wilson, Daisy; Jackson, Thomas; Sapey, Elizabeth; Lord, Janet M

2017-07-01

Frailty is a common negative consequence of ageing. Sarcopenia, the syndrome of loss of muscle mass, quality and strength, is more common in older adults and has been considered a precursor syndrome or the physical manifestation of frailty. The pathophysiology of both syndromes is incompletely described with multiple causes, inter-relationships and complex pathways proposed. Age-associated changes to the immune system (both immunesenescence, the decline in immune function with ageing, and inflammageing, a state of chronic inflammation) have been suggested as contributors to sarcopenia and frailty but a direct causative role remains to be established. Frailty, sarcopenia and immunesenescence are commonly described in older adults but are not ubiquitous to ageing. There is evidence that all three conditions are reversible and all three appear to share common inflammatory drivers. It is unclear whether frailty, sarcopenia and immunesenescence are separate entities that co-occur due to coincidental or potentially confounding factors, or whether they are more intimately linked by the same underlying cellular mechanisms. This review explores these possibilities focusing on innate immunity, and in particular associations with neutrophil dysfunction, inflammation and known mechanisms described to date. Furthermore, we consider whether the age-related decline in immune cell function (such as neutrophil migration), increased inflammation and the dysregulation of the phosphoinositide 3-kinase (PI3K)-Akt pathway in neutrophils could contribute pathogenically to sarcopenia and frailty. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

The effect of spaceflight on the gravity-sensing auxin gradient of roots: GFP reporter gene microscopy on orbit

PubMed Central

Ferl, Robert J; Paul, Anna-Lisa

2016-01-01

Our primary aim was to determine whether gravity has a direct role in establishing the auxin-mediated gravity-sensing system in primary roots. Major plant architectures have long been thought to be guided by gravity, including the directional growth of the primary root via auxin gradients that are then disturbed when roots deviate from the vertical as a gravity sensor. However, experiments on the International Space Station (ISS) now allow physical clarity with regard to any assumptions regarding the role of gravity in establishing fundamental root auxin distributions. We examined the spaceflight green fluorescent protein (GFP)-reporter gene expression in roots of transgenic lines of Arabidopsis thaliana: pDR5r::GFP, pTAA1::TAA1–GFP, pSCR::SCR–GFP to monitor auxin and pARR5::GFP to monitor cytokinin. Plants on the ISS were imaged live with the Light Microscopy Module (LMM), and compared with control plants imaged on the ground. Preserved spaceflight and ground control plants were examined post flight with confocal microscopy. Plants on orbit, growing in the absence of any physical reference to the terrestrial gravity vector, displayed typically “vertical” distribution of auxin in the primary root. This confirms that the establishment of the auxin-gradient system, the primary guide for gravity signaling in the root, is gravity independent. The cytokinin distribution in the root tip differs between spaceflight and the ground controls, suggesting spaceflight-induced features of root growth may be cytokinin related. The distribution of auxin in the gravity-sensing portion of the root is not dependent on gravity. Spaceflight appears benign to auxin and its role in the development of the primary root tip, whereas spaceflight may influence cytokinin-associated processes. PMID:28725721

A specific immune transcriptomic profile discriminates chronic kidney disease patients in predialysis from hemodialyzed patients

PubMed Central

2013-01-01

Background Chronic kidney disease (CKD) patients present a complex interaction between the innate and adaptive immune systems, in which immune activation (hypercytokinemia and acute-phase response) and immune suppression (impairment of response to infections and poor development of adaptive immunity) coexist. In this setting, circulating uremic toxins and microinflammation play a critical role. This condition, already present in the last stages of renal damage, seems to be enhanced by the contact of blood with bioincompatible extracorporeal hemodialysis (HD) devices. However, although largely described, the cellular machinery associated to the CKD- and HD-related immune-dysfunction is still poorly defined. Understanding the mechanisms behind this important complication may generate a perspective for improving patients outcome. Methods To better recognize the biological bases of the CKD-related immune dysfunction and to identify differences between CKD patients in conservative (CKD) from those in HD treatment, we used an high-throughput strategy (microarray) combined with classical bio-molecular approaches. Results Immune transcriptomic screening of peripheral blood mononuclear cells (1030 gene probe sets selected by Gene-Ontology) showed that 275 gene probe sets (corresponding to 213 genes) discriminated 9 CKD patients stage III-IV (mean ± SD of eGFR: 32.27±14.7 ml/min) from 17 HD patients (p < 0.0001, FDR = 5%). Seventy-one genes were up- and 142 down-regulated in HD patients. Functional analysis revealed, then, close biological links among the selected genes with a pivotal role of PTX3, IL-15 (up-regulated in HD) and HLA-G (down-regulated in HD). ELISA, performed on an independent testing-group [11 CKD stage III-IV (mean ± SD of eGFR: 30.26±14.89 ml/min) and 13 HD] confirmed that HLA-G, a protein with inhibition effects on several immunological cell lines including natural killers (NK), was down-expressed in HD (p = 0.04). Additionally, in the testing-group, protein levels of CX3CR1, an highly selective chemokine receptor and surface marker for cytotoxic effector lymphocytes, resulted higher expressed in HD compared to CKD (p < 0.01). Conclusion Taken together our results show, for the first time, that HD patients present a different immune-pattern compared to the un-dialyzed CKD patients. Among the selected genes, some of them encode for important biological elements involved in proliferation/activation of cytotoxic effector lymphocytes and in the immune-inflammatory cellular machinery. Additionally, this study reveals new potential diagnostic bio-markers and therapeutic targets. PMID:23663527

Space immunology - Past, present and future

NASA Technical Reports Server (NTRS)

Coulter, Gary R.; Taylor, Gerald R.; Sonnenfeld, Gerald

1989-01-01

Research results on the causes and mechanisms of change in immune systems during spaceflight are briefly reviewed. The most reliable conclusion from the sparse existing data is that postflight crew members exhibit a transient neutrophilia, eosinopenia, monocytopenia, reduced numbers of circulating T cells, and an often pronounced decrease in the ability of their T cells to respond to mitogen stimulation. Clinically, no direct predictive relationship between any of these measurements and increased health risk or disease has been established. Future areas of research are suggested in light of NASA's emerging requirements to support long-duration missions.

Validation of Methods to Assess the Immunoglobulin Gene Repertoire in Tissues Obtained from Mice on the International Space Station.

PubMed

Rettig, Trisha A; Ward, Claire; Pecaut, Michael J; Chapes, Stephen K

2017-07-01

Spaceflight is known to affect immune cell populations. In particular, splenic B cell numbers decrease during spaceflight and in ground-based physiological models. Although antibody isotype changes have been assessed during and after space flight, an extensive characterization of the impact of spaceflight on antibody composition has not been conducted in mice. Next Generation Sequencing and bioinformatic tools are now available to assess antibody repertoires. We can now identify immunoglobulin gene- segment usage, junctional regions, and modifications that contribute to specificity and diversity. Due to limitations on the International Space Station, alternate sample collection and storage methods must be employed. Our group compared Illumina MiSeq sequencing data from multiple sample preparation methods in normal C57Bl/6J mice to validate that sample preparation and storage would not bias the outcome of antibody repertoire characterization. In this report, we also compared sequencing techniques and a bioinformatic workflow on the data output when we assessed the IgH and Igκ variable gene usage. This included assessments of our bioinformatic workflow on Illumina HiSeq and MiSeq datasets and is specifically designed to reduce bias, capture the most information from Ig sequences, and produce a data set that provides other data mining options. We validated our workflow by comparing our normal mouse MiSeq data to existing murine antibody repertoire studies validating it for future antibody repertoire studies.

Role of Dendritic Cells in Immune Dysfunction

NASA Technical Reports Server (NTRS)

Savary, Cherylyn A.

1998-01-01

The specific aims of the project were: (1) Application of the NASA bioreactor to enhance cytokine-regulated proliferation and maturation of dendritic cells (DC). (2) Compare the frequency and function of DC in normal donors and immunocompromised cancer patients. (3) Analyze the effectiveness of cytokine therapy and DC-assisted immunotherapy (using bioreactor-expanded DC) in a murine model of experimental fungal disease. Our investigations have provided new insight into DC immunobiology and have led to the development of methodology to evaluate DC in blood of normal donors and patients. Information gained from these studies has broadened our understanding of possible mechanisms involved in the immune dysfunction of space travelers and earth-bound cancer patients, and could contribute to the design of novel therapies to restore/preserve immunity in these individuals. Several new avenues of investigation were also revealed. The results of studies completed during Round 2 are summarized.

Brain perivascular macrophages: characterization and functional roles in health and disease.

PubMed

Faraco, Giuseppe; Park, Laibaik; Anrather, Josef; Iadecola, Costantino

2017-11-01

Perivascular macrophages (PVM) are a distinct population of resident brain macrophages characterized by a close association with the cerebral vasculature. PVM migrate from the yolk sac into the brain early in development and, like microglia, are likely to be a self-renewing cell population that, in the normal state, is not replenished by circulating monocytes. Increasing evidence implicates PVM in several disease processes, ranging from brain infections and immune activation to regulation of the hypothalamic-adrenal axis and neurovascular-neurocognitive dysfunction in the setting of hypertension, Alzheimer disease pathology, or obesity. These effects involve crosstalk between PVM and cerebral endothelial cells, interaction with circulating immune cells, and/or production of reactive oxygen species. Overall, the available evidence supports the idea that PVM are a key component of the brain-resident immune system with broad implications for the pathogenesis of major brain diseases. A better understanding of the biology and pathobiology of PVM may lead to new insights and therapeutic strategies for a wide variety of brain diseases.

Impaired Epstein-Barr Virus-Specific Neutralizing Antibody Response during Acute Infectious Mononucleosis Is Coincident with Global B-Cell Dysfunction.

PubMed

Panikkar, Archana; Smith, Corey; Hislop, Andrew; Tellam, Nick; Dasari, Vijayendra; Hogquist, Kristin A; Wykes, Michelle; Moss, Denis J; Rickinson, Alan; Balfour, Henry H; Khanna, Rajiv

2015-09-01

Here we present evidence for previously unappreciated B-cell immune dysregulation during acute Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM). Longitudinal analyses revealed that patients with acute IM have undetectable EBV-specific neutralizing antibodies and gp350-specific B-cell responses, which were associated with a significant reduction in memory B cells and no evidence of circulating antibody-secreting cells. These observations correlate with dysregulation of tumor necrosis factor family members BAFF and APRIL and increased expression of FAS on circulating B cells. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Spaceflight Associated Apoptosis

NASA Technical Reports Server (NTRS)

Ichiki, Albert T.; Gibson, Linda A.; Allebban, Zuhair

1996-01-01

Lymphoid tissues have been shown to atrophy in rats flown on Russian spaceflights. Histological examination indicated evidence for cell degradation. Lymphoid tissues from rats flown on Spacelab Life Sciences-2 mission were analyzed for apoptosis by evidence of fragmented lymphocytes, which could be engulfed by macrophages, or DNA strand breaks using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. Apoptosis was not detected in the thymus and spleen collected inflight or from the synchronous ground rats but was detected in the thymus, spleen and inguinal lymph node of the flight animals on recovery. These results indicate that the apoptosis observed in the lymphatic tissues of the rats on recovery could have been induced by the gravitational stress of reentry, corroborating the findings from the early space-flight observations.

Capacity of omega-3 fatty acids or eicosapentaenoic acid to counteract weightlessness-induced bone loss by inhibiting NF-kappaB activation: from cells to bed rest to astronauts.

PubMed

Zwart, Sara R; Pierson, Duane; Mehta, Satish; Gonda, Steve; Smith, Scott M

2010-05-01

NF-kappaB is a transcriptional activator of many genes, including some that lead to muscle atrophy and bone resorption-significant concerns for astronauts. NF-kappaB activation is inhibited by eicosapentaenoic acid (EPA), but the influence of this omega-3 fatty acid on the effects of weightlessness are unknown. We report here cellular, ground analogue, and spaceflight findings. We investigated the effects of EPA on differentiation of RAW264.7 monocyte/macrophage cells induced by receptor activator of NF-kappaB ligand (RANKL) and on activation of NF-kappaB by tumor necrosis factor alpha (TNF-alpha) or exposure to modeled weightlessness. EPA (50 microM for 24 hours) inhibited RANKL-induced differentiation and decreased activation of NF-kappaB induced by 0.2 microg/mL of TNF-alpha for 30 minutes or by modeled weightlessness for 24 hours (p < .05). In human studies, we evaluated whether NF-kappaB activation was altered after short-duration spaceflight and determined the relationship between intake of omega-3 fatty acids and markers of bone resorption during bed rest and the relationship between fish intake and bone mineral density after long-duration spaceflight. NF-kappaB was elevated in crew members after short-duration spaceflight, and higher consumption of fish (a rich source of omega-3 fatty acids) was associated with reduced loss of bone mineral density after flight (p < .05). Also supporting the cell study findings, a higher intake of omega-3 fatty acids was associated with less N-telopeptide excretion during bed rest (Pearson r = -0.62, p < .05). Together these data provide mechanistic cellular and preliminary human evidence of the potential for EPA to counteract bone loss associated with spaceflight. (c) 2010 American Society for Bone and Mineral Research.