scholarly journals Physiological Responses of Jurkat Lymphocytes to Simulated Microgravity Conditions

2019 ◽  
Vol 20 (8) ◽  
pp. 1892 ◽  
Author(s):  
Caterina Morabito ◽  
Paola Lanuti ◽  
Giusy A. Caprara ◽  
Marco Marchisio ◽  
Mariano Bizzarri ◽  
...  
Keyword(s):  
Simulated Microgravity ◽  
Immune Cell ◽  
Cellular Level ◽  
The Body ◽  
Jurkat Cells ◽  
Cell Phenotype ◽  
Environmental Condition ◽  
Mitochondria Membrane Potential ◽  
Microgravity Conditions ◽  
External Forces

The presence of microgravity conditions deeply affects the human body functions at the systemic, organ and cellular levels. This study aimed to investigate the effects induced by simulated-microgravity on non-stimulated Jurkat lymphocytes, an immune cell phenotype considered as a biosensor of the body responses, in order to depict at the cellular level the effects of such a peculiar condition. Jurkat cells were grown at 1 g or on random positioning machine simulating microgravity. On these cells we performed: morphological, cell cycle and proliferation analyses using cytofluorimetric and staining protocols—intracellular Ca2+, reactive oxygen species (ROS), mitochondria membrane potential and O2− measurements using fluorescent probes—aconitase and mitochondria activity, glucose and lactate content using colorimetric assays. After the first exposure days, the cells showed a more homogeneous roundish shape, an increased proliferation rate, metabolic and detoxifying activity resulted in decreased intracellular Ca2+ and ROS. In the late exposure time, the cells adapted to the new environmental condition. Our non-activated proliferating Jurkat cells, even if responsive to altered external forces, adapted to the new environmental condition showing a healthy status. In order to define the cellular mechanism(s) triggered by microgravity, developing standardized experimental approaches and controlled cell culture and simulator conditions is strongly recommended.

The Supersonic Flow Past a Slender Ducted Body of Revolution with an Annular Intake

1950 ◽  
Vol 1 (4) ◽  
pp. 305-318
Author(s):  
G. N. Ward
Keyword(s):  
Supersonic Flow ◽  
Velocity Potential ◽  
Operational Calculus ◽  
The Body ◽  
Body Of Revolution ◽  
Internal Flows ◽  
Flow Past ◽  
External Forces ◽  
Internal Pressures ◽  
Slender Body Of Revolution

SummaryThe approximate supersonic flow past a slender ducted body of revolution having an annular intake is determined by using the Heaviside operational calculus applied to the linearised equation for the velocity potential. It is assumed that the external and internal flows are independent. The pressures on the body are integrated to find the drag, lift and moment coefficients of the external forces. The lift and moment coefficients have the same values as for a slender body of revolution without an intake, but the formula for the drag has extra terms given in equations (32) and (56). Under extra assumptions, the lift force due to the internal pressures is estimated. The results are applicable to propulsive ducts working under the specified condition of no “ spill-over “ at the intake.

scholarly journals Pathophysiology of acute respiratory syndrome coronavirus 2 infection: a systematic literature review to inform EULAR points to consider

RMD Open ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. e001549 ◽  
Author(s):  
Aurélie Najm ◽  
Alessia Alunno ◽  
Xavier Mariette ◽  
Benjamin Terrier ◽  
Gabriele De Marco ◽  
...  
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Immune Cell ◽  
Severe Disease ◽  
Cell Phenotype ◽  
Loss Of Function ◽  
Humoral And Cellular Immunity ◽  
Host Immune Responses ◽  
Disease Spectrum ◽  
And Function

BackgroundThe SARS-CoV-2 pandemic is a global health problem. Beside the specific pathogenic effect of SARS-CoV-2, incompletely understood deleterious and aberrant host immune responses play critical roles in severe disease. Our objective was to summarise the available information on the pathophysiology of COVID-19.MethodsTwo reviewers independently identified eligible studies according to the following PICO framework: P (population): patients with SARS-CoV-2 infection; I (intervention): any intervention/no intervention; C (comparator): any comparator; O (outcome) any clinical or serological outcome including but not limited to immune cell phenotype and function and serum cytokine concentration.ResultsOf the 55 496 records yielded, 84 articles were eligible for inclusion according to question-specific research criteria. Proinflammatory cytokine expression, including interleukin-6 (IL-6), was increased, especially in severe COVID-19, although not as high as other states with severe systemic inflammation. The myeloid and lymphoid compartments were differentially affected by SARS-CoV-2 infection depending on disease phenotype. Failure to maintain high interferon (IFN) levels was characteristic of severe forms of COVID-19 and could be related to loss-of-function mutations in the IFN pathway and/or the presence of anti-IFN antibodies. Antibody response to SARS-CoV-2 infection showed a high variability across individuals and disease spectrum. Multiparametric algorithms showed variable diagnostic performances in predicting survival, hospitalisation, disease progression or severity, and mortality.ConclusionsSARS-CoV-2 infection affects both humoral and cellular immunity depending on both disease severity and individual parameters. This systematic literature review informed the EULAR ‘points to consider’ on COVID-19 pathophysiology and immunomodulatory therapies.

scholarly journals Endogenous retrovirus-encoded Syncytin-2 contributes to exosome-mediated immunosuppression of T cells†

2019 ◽  
Author(s):  
Adjimon G Lokossou ◽  
Caroline Toudic ◽  
Phuong Trang Nguyen ◽  
Xavier Elisseeff ◽  
Amandine Vargas ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell Activation ◽  
Map Kinases ◽  
Cell Activation ◽  
Mononuclear Cells ◽  
Immune Cell ◽  
Endogenous Retrovirus ◽  
Jurkat Cells ◽  
Peripheral Blood Mononuclear ◽  
Interfering Rna

Abstract Modulation of the activation status of immune cell populations during pregnancy depends on placental villous cytotrophoblast (VCT) cells and the syncytiotrophoblast (STB). Failure in the establishment of this immunoregulatory function leads to pregnancy complications. Our laboratory has been studying Syncytin-2 (Syn-2), an endogenous retroviral protein expressed in placenta and on the surface of placental exosomes. This protein plays an important role not only in STB formation through its fusogenic properties, but also through its immunosuppressive domain (ISD). Considering that Syn-2 expression is importantly reduced in preeclamptic placentas, we were interested in addressing its possible immunoregulatory effects on T cells. Activated Jurkat T cells and peripheral blood mononuclear cells (PBMCs) were treated with monomeric or dimerized version of a control or a Syn-2 ISD peptide. Change in phosphorylation levels of ERK1/2 MAP kinases was selectively noted in Jurkat cells treated with the dimerized ISD peptide. Upon incubation with the dimerized Syn-2 ISD peptide, significant reduction in Th1 cytokine production was further demonstrated by ELISA and Human Th1/Th2 Panel Multi-Analyte Flow Assay. To determine if exosome-associated Syn-2 could also be immunosuppressive placental exosomes were incubated with activated Jurkat and PBMCs. Quantification of Th1 cytokines in the supernatants revealed severe reduction in T cell activation. Interestingly, exosomes from Syn-2-silenced VCT incubated with PBMCs were less suppressive when compared with exosome derived from VCT transfected with control small interfering RNA (siRNA). Our results suggest that Syn-2 is an important immune regulator both locally and systemically, via its association with placental exosomes.

scholarly journals A bi-directional dialog between vascular cells and monocytes/macrophages regulates tumor progression

2021 ◽  
Author(s):  
Victor Delprat ◽  
Carine Michiels
Keyword(s):  
Tumor Progression ◽  
Cancer Progression ◽  
Cell Activation ◽  
Molecular Mechanisms ◽  
Immune Cell ◽  
The Body ◽  
Vascular Cells ◽  
Tumor Associated Macrophage ◽  
Immune Cell Activation ◽  
The Impact

AbstractCancer progression largely depends on tumor blood vessels as well on immune cell infiltration. In various tumors, vascular cells, namely endothelial cells (ECs) and pericytes, strongly regulate leukocyte infiltration into tumors and immune cell activation, hence the immune response to cancers. Recently, a lot of compelling studies unraveled the molecular mechanisms by which tumor vascular cells regulate monocyte and tumor-associated macrophage (TAM) recruitment and phenotype, and consequently tumor progression. Reciprocally, TAMs and monocytes strongly modulate tumor blood vessel and tumor lymphatic vessel formation by exerting pro-angiogenic and lymphangiogenic effects, respectively. Finally, the interaction between monocytes/TAMs and vascular cells is also impacting several steps of the spread of cancer cells throughout the body, a process called metastasis. In this review, the impact of the bi-directional dialog between blood vascular cells and monocytes/TAMs in the regulation of tumor progression is discussed. All together, these data led to the design of combinations of anti-angiogenic and immunotherapy targeting TAMs/monocyte whose effects are briefly discussed in the last part of this review.

scholarly journals Patient education on back care

2009 ◽  
Vol 65 (1) ◽  
Author(s):  
C. Van Eck
Keyword(s):  
Low Back Pain ◽  
Back Pain ◽  
Patient Education ◽  
Study Design ◽  
Significant Role ◽  
The Body ◽  
Low Back ◽  
Clinical Perspective ◽  
Back Care ◽  
External Forces

Study Design: Clinical PerspectiveObjective: To provide back care education for patients with low back pain. Background:  Understanding the internal and external forces the body issubjected to, as well as the spine’s response to these forces, can better equipphysiotherapists in educating patients with low back pain. Methods and Measures: The focus of the clinical perspective is to providephysiotherapists with clinically sound reasoning when educating patients. Results: Providing a patient handout, educating them in how to incorporate back care knowledge into their dailyactivities.Conclusion: Physiotherapists can play a significant role in empowering patients through education to take responsi-bility for their disability.

scholarly journals Using ex vivo culture to assess dynamic phenotype changes in human prostate macrophages following exposure to therapeutic drugs

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Clovis Boibessot ◽  
France-Hélène Joncas ◽  
Aerin Park ◽  
Zohra Berrehail ◽  
Jean-François Pelletier ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Immune Cell ◽  
Ex Vivo ◽  
Cell Phenotype ◽  
Gleason Grade ◽  
Tumor Resistance ◽  
Grade Group ◽  
In Vivo Models ◽  
Novel Associations

AbstractWithin the prostate tumor microenvironment (TME) there are complex multi-faceted and dynamic communication occurring between cancer cells and immune cells. Macrophages are key cells which infiltrate and surround tumor cells and are recognized to significantly contribute to tumor resistance and metastases. Our understanding of their function in the TME is commonly based on in vitro and in vivo models, with limited research to confirm these model observations in human prostates. Macrophage infiltration was evaluated within the TME of human prostates after 72 h culture of fresh biopsies samples in the presence of control or enzalutamide. In addition to immunohistochemistry, an optimized protocol for multi-parametric evaluation of cellular surface markers was developed using flow cytometry. Flow cytometry parameters were compared to clinicopathological features. Immunohistochemistry staining for 19 patients with paired samples suggested enzalutamide increased the expression of CD163 relative to CD68 staining. Techniques to validate these results using flow cytometry of dissociated biopsies after 72 h of culture are described. In a second cohort of patients with Gleason grade group ≥ 3 prostate cancer, global macrophage expression of CD163 was unchanged with enzalutamide treatment. However, exploratory analyses of our results using multi-parametric flow cytometry for multiple immunosuppressive macrophage markers suggest subgroup changes as well as novel associations between circulating biomarkers like the neutrophil to lymphocyte ratio (NLR) and immune cell phenotype composition in the prostate TME. Further, we observed an association between B7–H3 expressing tumor-associated macrophages and the presence of intraductal carcinoma. The use of flow cytometry to evaluate ex vivo cultured prostate biopsies fills an important gap in our ability to understand the immune cell composition of the prostate TME. Our results highlight novel associations for further investigation.

scholarly journals The Effects of Simulated Microgravity on Macrophage Phenotype

Biomedicines ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1205
Author(s):  
Christopher Ludtka ◽  
Erika Moore ◽  
Josephine B. Allen
Keyword(s):  
Protein Expression ◽  
Simulated Microgravity ◽  
Prolonged Exposure ◽  
Cell Function ◽  
Immune Cell ◽  
Expression Profiles ◽  
Microgravity Environment ◽  
M2 Macrophage ◽  
Macrophage Function ◽  
Gene And Protein Expression

The effects of spaceflight, including prolonged exposure to microgravity, can have significant effects on the immune system and human health. Altered immune cell function can lead to adverse health events, though precisely how and to what extent a microgravity environment impacts these cells remains uncertain. Macrophages, a key immune cell, effect the inflammatory response as well as tissue remodeling and repair. Specifically, macrophage function can be dictated by phenotype that can exist between spectrums of M0 macrophage: the classically activated, pro-inflammatory M1, and the alternatively activated, pro-healing M2 phenotypes. This work assesses the effects of simulated microgravity via clinorotation on M0, M1, and M2 macrophage phenotypes. We focus on phenotypic, inflammatory, and angiogenic gene and protein expression. Our results show that across all three phenotypes, microgravity results in a decrease in TNF-α expression and an increase in IL-12 and VEGF expression. IL-10 was also significantly increased in M1 and M2, but not M0 macrophages. The phenotypic cytokine expression profiles observed may be related to specific gravisensitive signal transduction pathways previously implicated in microgravity regulation of macrophage gene and protein expression. Our results highlight the far-reaching effects that simulated microgravity has on macrophage function and provides insight into macrophage phenotypic function in microgravity.

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