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Rheumatology (Oxford, England) Aug 2020Peficitinib, a novel Janus kinase (JAK) inhibitor, demonstrated promising results in treating RA in phase 3 clinical trials. This in vitro study was undertaken to...
OBJECTIVES
Peficitinib, a novel Janus kinase (JAK) inhibitor, demonstrated promising results in treating RA in phase 3 clinical trials. This in vitro study was undertaken to characterize the pharmacological properties of peficitinib and investigate the involvement of JAK and signal transducer and activator of transcription (STAT) pathways in the pathological processes of SSc, which is also an autoimmune disease.
METHODS
Phosphorylation levels of STAT molecules were assessed in peripheral blood mononuclear cells collected from patients with RA or SSc and healthy subjects, and in skin specimens obtained from 19 patients with SSc. In vitro inhibition of STAT phosphorylation and cytokine/chemokine production by peficitinib, tofacitinib and baricitinib were also characterized.
RESULTS
Higher spontaneous STAT1 or STAT3 phosphorylation was observed in peripheral T-cells and monocytes from patients with RA and SSc compared with healthy subjects. In skin sections from patients with SSc, phosphorylated STAT3-positive cells were found in almost all cases, irrespective of disease subtype or patient characteristics. Conversely, phosphorylated STAT1-positive cells were observed only in samples from untreated patients with diffuse disease of short duration. Peficitinib inhibited STAT phosphorylation induced by various cytokines, with comparable efficacy to tofacitinib and baricitinib. Peficitinib also suppressed cytokine and chemokine production by peripheral blood mononuclear cells and skin fibroblasts.
CONCLUSION
Our results suggest that JAK/STAT pathways are constitutively activated in SSc and RA, and that the JAK inhibitor may represent a novel therapeutic option for SSc.
Topics: Adamantane; Arthritis, Rheumatoid; Female; Humans; Janus Kinase Inhibitors; Lymphocyte Activation; Lymphocytes; Male; Niacinamide; Phosphorylation; STAT Transcription Factors; Scleroderma, Systemic
PubMed: 31764973
DOI: 10.1093/rheumatology/kez526 -
Exercise Immunology Review 2018Ageing has profound impact on the immune system, mainly on T-cells. However, it has been suggested that chronic exercise may delay immunosenescence. Master athletes...
BACKGROUND/PURPOSE
Ageing has profound impact on the immune system, mainly on T-cells. However, it has been suggested that chronic exercise may delay immunosenescence. Master athletes represent an interesting sub-demographic group to test this theory since they maintain a high training frequency and load throughout life. The purpose of this study was to evaluate the effects of lifelong training on the senescence and mobilization of T lymphocytes in response to acute exercise.
MATERIAL AND METHODS
Nineteen athletes who regularly participated in training and competitions for more than 20 years throughout their lives and a control group of 10 healthy individuals participated in this study. All subjects performed a progressive test to exhaustion on a cycle ergometer. Blood samples were obtained before (Pre), 10 min after the test (Post) and 1 h after the test (1h). Phenotypic study of peripheral blood T-cells was performed by flow cytometry. Genes of interest expression was done on T-cells purified by cell sorting.
RESULTS
Master athletes had a lower percentage of senescent naïve, central memory and effector memory CD8+ T-cells and senescent naïve and effector memory CD4+ T-cells. Age had a positive effect on SLEC CD8+ T-cells and a negative effect on naïve CD8+ T-cells. VO2max positively correlated with the proportion of naïve CD4+ T-cells and negatively correlated with the percentage of total lymphocytes. No differences were founded for CD4+ and CD8+ T-cells and their subsets between master athletes and the control group at all times of measurement. No differences were observed in the CD45RA expressing effector memory cells (EMRA) for the various study conditions. The mRNA expression of the CCR7 gene for naïve CD8+ T-cells and the Fas-L gene for effector-terminal CD8+ T-cells was not different between masters and controls and did not change in response to the maximal protocol test.
CONCLUSION
In conclusion, maintaining high levels of aerobic fitness during the natural course of aging may help prevent the accumulation of senescent T-cells.
Topics: Athletes; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Cell Separation; Exercise; Female; Flow Cytometry; Humans; Immunologic Memory; Immunosenescence; Male; Middle Aged; Oxygen Consumption; T-Lymphocyte Subsets
PubMed: 29461967
DOI: No ID Found -
PloS One 2020Myeloid-derived suppressor cells (MDSCs) are potent suppressors of immune function and may play a key role in the development and progression of metastatic cancers....
BACKGROUND
Myeloid-derived suppressor cells (MDSCs) are potent suppressors of immune function and may play a key role in the development and progression of metastatic cancers. Aerobic exercise has been shown to have anticancer effects, yet the mechanisms behind this protection are largely unknown. Therefore, we examined the effects of physical activity on MDSC accumulation and function.
METHODS
Female BALB/c mice were assigned to one of two primary groups: sedentary tumor (SED+TUM) or wheel run tumor (WR+TUM). After 6 weeks of voluntary wheel running, all animals were randomly subdivided into 4 different timepoint groups; 16, 20, 24, and 28 days post-tumor injection. All mice were inoculated with 4T1 mammary carcinoma cells in the mammary fat pad and WR groups continued to run for the specified time post-injection. Spleen, blood, and tumor samples were analyzed using flow cytometry to assess proportions of MDSCs.
RESULTS
Cells expressing MDSC biomarkers were detected in the spleen, blood, and tumor beginning at d16. However, since there was no evidence of immunosuppressive function until d28, we refer to them as immature myeloid cells (IMCs). Compared to SED+TUM, levels of IMCs in the spleen were significantly lower (p < 0.05) in WR+TUM at day 16 (33.0 ± 5.2%; 23.1 ± 10.2% of total cells, respectively) and day 20 (33.9 ± 8.1%; 24.3 ± 5.1% of total cells, respectively). Additionally, there were fewer circulating IMCs in WR+TUM at day 16 and MDSC levels were significantly lower (p < 0.05) in the tumor at day 28 in WR+TUM. Additionally, a non-significant 62% and 26% reduction in metastatic lung nodules was observed at days 24 and 28, respectively. At day 28, MDSCs harvested from SED+TUM significantly suppressed CD3+CD4+ T cell proliferation (3.2 ± 1.3 proliferation index) while proliferation in WR+TUM MDSC co-cultures (5.1 ± 1.7 proliferation index) was not different from controls.
CONCLUSIONS
These findings suggest that physical activity may delay the accumulation of immunosuppressive MDSCs providing a broader window of opportunity for interventions with immunotherapies.
Topics: Animals; Cell Line, Tumor; Cell Proliferation; Coculture Techniques; Female; Immunosuppression Therapy; Immunosuppressive Agents; Lymphocyte Activation; Mammary Neoplasms, Experimental; Mice; Motor Activity; Myeloid Cells; Myeloid-Derived Suppressor Cells
PubMed: 32542046
DOI: 10.1371/journal.pone.0234548 -
Leukemia Jan 2021Novel targeted agents used in therapy of lymphoid malignancies, such as inhibitors of B-cell receptor-associated kinases, are recognized to have complex immune-mediated...
Novel targeted agents used in therapy of lymphoid malignancies, such as inhibitors of B-cell receptor-associated kinases, are recognized to have complex immune-mediated effects. NEDD8-activating enzyme (NAE) has been identified as a tractable target in chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma. We and others have shown that pevonedistat (TAK-924), a small-molecule inhibitor of NAE, abrogates NF-κB signaling in malignant B cells. However, NF-κB pathway activity is indispensable in immune response, and T-cell function is altered in patients with CLL. Using T cells derived from patients with CLL, we demonstrate that although targeting NAE results in markedly differential expression of NF-κB-regulated genes and downregulation of interleukin (IL)-2 signaling during T-cell activation, T cells evade apoptosis. Meanwhile, NAE inhibition favorably modulates polarization of T cells in vitro, with decreased T differentiation and a shift toward T1 phenotype, accompanied by increased interferon-γ production. These findings were recapitulated in vivo in immunocompetent mouse models. T cells exposed to pevonedistat in washout experiments, informed by its human pharmacokinetic profile, recover NAE activity, and maintain their response to T-cell receptor stimulation and cytotoxic potential. Our data shed light on the potential immune implications of targeting neddylation in CLL and lymphoid malignancies.
Topics: Antineoplastic Agents; Cell Line, Tumor; Cyclopentanes; Enzyme Inhibitors; Humans; Immunomodulation; Leukemia, Prolymphocytic, T-Cell; Lymphocyte Activation; Models, Biological; NEDD8 Protein; Pyrimidines; Receptors, Antigen, T-Cell; Signal Transduction; T-Lymphocytes; T-Lymphocytes, Helper-Inducer
PubMed: 32203139
DOI: 10.1038/s41375-020-0794-0 -
European Cytokine Network Mar 2001Interferon-gamma (IFN-gamma) is a lymphokine produced by activated T lymphocytes and NK cells, that plays an important role in host defense mechanisms by exerting... (Review)
Review
Interferon-gamma (IFN-gamma) is a lymphokine produced by activated T lymphocytes and NK cells, that plays an important role in host defense mechanisms by exerting pleiotropic activities on a wide range of cell types. Cellular responses to IFN-gamma are mediated by its heterodimeric cell surface receptor (IFN-gammaR), which activates downstream signal transduction cascades, ultimately leading to the regulation of gene expression. Several observations suggest that the signals resulting from the binding of IFN-gamma to its receptor depend on the number of surface receptors transducing the IFN-gamma signal. This review summarizes recent advances in the understanding of the fine regulation of the response of human lymphocytes to IFN-gamma through an interplay between surface expression of IFN-gammaR and a variety of environmental factors that combine to control their fate.
Topics: Apoptosis; Cell Survival; Humans; Lymphocyte Activation; Neoplasms; Receptors, Interferon; T-Lymphocytes; Interferon gamma Receptor
PubMed: 11282540
DOI: No ID Found -
European Journal of Immunology Apr 2008AMP-activated protein kinase (AMPK), a phylogenetically conserved serine/threonine protein kinase, represents an energy sensor able to adapt cellular metabolism in...
AMP-activated protein kinase (AMPK), a phylogenetically conserved serine/threonine protein kinase, represents an energy sensor able to adapt cellular metabolism in response to nutritional environmental variations. TCR stimulation activates AMPK, a regulatory event that is known to stimulate ATP-producing processes, possibly in anticipation of the increased energetic needs associated with cell division and expression of effector function. Taking advantage of the selective expression of the AMPKalpha1 catalytic subunit in lymphoid cells, we have analyzed the in vitro and in vivo capacity of lymphocytes lacking AMPK activity (AMPKalpha1-KO cells) to respond to metabolic stress and to initiate and sustain an immune response. AMPKalpha1-KO cells displayed increasing sensitivity to energetic stress in vitro, and were found unable to maintain adequate ATP levels in response to ATP synthase inhibition. These cells were, however, able to respond to antigen stimulation in vitro, as shown by optimal proliferation and cytokine production. Similarly, AMPKalpha1-KO mice were fully immunocompetent in vivo and displayed normal cell proliferation, humoral, cytotoxic and delayed-type hypersensitivity (DTH) responses following antigen injection. In conclusion, AMPK represents an important enzyme allowing lymphocytes to resist a mild energy crisis in vitro, but is largely dispensable for activation and expression of effector function in response to antigen stimulation.
Topics: AMP-Activated Protein Kinases; Animals; Cell Proliferation; Cells, Cultured; Cytokines; Lymphocytes; Mice; Mice, Inbred C57BL; Mice, Knockout; Multienzyme Complexes; Protein Serine-Threonine Kinases; Sensitivity and Specificity
PubMed: 18350549
DOI: 10.1002/eji.200738045 -
Journal of Applied Physiology... Jul 2014Military working dogs in hot countries undergo exercise training at high ambient temperatures for at least 9 mo annually. Physiological adaptations to these harsh...
Military working dogs in hot countries undergo exercise training at high ambient temperatures for at least 9 mo annually. Physiological adaptations to these harsh conditions have been extensively studied; however, studies focusing on the underlying molecular adaptations are limited. In the current study, military working dogs were chosen as a model to examine the effects of superimposing endurance exercise on seasonal acclimatization to environmental heat stress. The lymphocyte HSP70 profile and extracellular HSP70 were studied in tandem with physiological performance in the dogs from their recruitment for the following 2 yr. Aerobic power and heat shock proteins were measured at the end of each summer, with physical performance tests (PPTs) in an acclimatized room (22°C). The study shows that together with a profound enhancement of aerobic power and physical performance, hsp72 mRNA induction immediately post-PPT and 45 min later, progressively increased throughout the study period (relative change in median lymphocyte hsp72 mRNA first PPT, 4.22 and 12.82; second PPT, 17.19 and 109.05, respectively), whereas induction of HSP72 protein was stable. These responses suggest that cellular/molecular adaptive tools for maintaining HSP72 homeostasis exist. There was also a significant rise in basal and peak median optical density extracellular HSP at the end of each exercise test (first PPT, 0.13 and 0.15; second PPT, 1.04 and 1.52, respectively). The relationship between these enhancements and improved aerobic power capacity is not yet fully understood.
Topics: Acclimatization; Adaptation, Physiological; Animals; Dogs; Exercise Tolerance; HSP70 Heat-Shock Proteins; Hot Temperature; Lymphocytes; Military Personnel; Physical Conditioning, Animal; Stress, Physiological
PubMed: 24903923
DOI: 10.1152/japplphysiol.00090.2014 -
British Journal of Cancer Aug 1990We report the natural killer (NK) and lymphokine activated killer (LAK) cell activities in peripheral blood lymphocytes (PBL) from untreated patients with Hodgkin's...
We report the natural killer (NK) and lymphokine activated killer (LAK) cell activities in peripheral blood lymphocytes (PBL) from untreated patients with Hodgkin's disease (HD) and from healthy donors. The frequency of LAK cell precursors was also studied using limiting dilution analysis (LDA). About 75% of the HD patients had normal NK activity. There was a higher percentage of low NK responders (mean percent NK activity of healthy donors--2 SD) in patients with lymphocyte depletion histologic grade of the disease and those who were in clinical stage IV, suggesting a correlation of decrease in NK activity with poor prognosis. We found efficient LAK activity against the NK-sensitive K562 cells and NK-resistant VIP (melanoma) and T-24 (bladder carcinoma) tumour targets in both low and normal NK responder HD patients, irrespective of the histopathological grade and clinical stage of the disease. In concordance with their good LAK cell activity, HD patients showed a frequency distribution of LAK cell progenitors in the PBL comparable to that of healthy donors.
Topics: Adolescent; Adult; Child; Hodgkin Disease; Humans; Killer Cells, Lymphokine-Activated; Killer Cells, Natural; Lymphocytes; Middle Aged; Neoplasm Staging
PubMed: 2386735
DOI: 10.1038/bjc.1990.261 -
Initial analysis of peripheral lymphocytic extracellular signal related kinase activation in autism.Journal of Psychiatric Research Jan 2017Dysregulation of extracellular signal-related kinase (ERK) activity has been potentially implicated in the pathophysiology of autistic disorder (autism). ERK is part of...
BACKGROUND
Dysregulation of extracellular signal-related kinase (ERK) activity has been potentially implicated in the pathophysiology of autistic disorder (autism). ERK is part of a central intracellular signaling cascade responsible for a myriad of cellular functions. ERK is expressed in peripheral blood lymphocytes, and measurement of activated (phosphorylated) lymphocytic ERK is commonly executed in many areas of medicine. We sought to conduct the first study of ERK activation in humans with autism by utilizing a lymphocytic ERK activation assay. We hypothesized that ERK activation would be enhanced in peripheral blood lymphocytes from persons with autism compared to those of neurotypical control subjects.
METHOD
We conducted an initial study of peripheral lymphocyte ERK activation in 45 subjects with autism and 26 age- and gender-matched control subjects (total n = 71). ERK activation was measured using a lymphocyte counting method (primary outcome expressed as lymphocytes staining positive for cytosolic phosphorylated ERK divided by total cells counted) and additional Western blot analysis of whole cell phosphorylated ERK adjusted for total ERK present in the lymphocyte lysate sample.
RESULTS
Cytosolic/nuclear localization of pERK activated cells were increased by almost two-fold in the autism subject group compared to matched neurotypical control subjects (cell count ratio of 0.064 ± 0.044 versus 0.034 ± 0.031; p = 0.002). Elevated phosphorylated ERK levels in whole cell lysates also showed increased activated ERK in the autism group compared to controls (n = 54 total) in Western blot analysis.
CONCLUSIONS
The results of this first in human ERK activation study are consistent with enhanced peripheral lymphocytic ERK activation in autism, as well as suggesting that cellular compartmentalization of activated ERK may be altered in this disorder. Future work will be required to explore the impact of concomitant medication use and other subject characteristics such as level of cognitive functioning on ERK activation.
TRIAL REGISTRATION
Not applicable.
Topics: Adolescent; Adult; Autistic Disorder; Biomarkers; Blotting, Western; Cell Count; Child; Child, Preschool; Cytosol; Extracellular Signal-Regulated MAP Kinases; Female; Humans; Immunohistochemistry; Lymphocytes; Male; Middle Aged; Phosphorylation; Psychotropic Drugs; Young Adult
PubMed: 27743527
DOI: 10.1016/j.jpsychires.2016.09.003 -
Journal of Neuroinflammation Apr 2018The success of clinical trials of selective B cell depletion in patients with relapsing multiple sclerosis (MS) indicates B cells are important contributors to...
BACKGROUND
The success of clinical trials of selective B cell depletion in patients with relapsing multiple sclerosis (MS) indicates B cells are important contributors to peripheral immune responses involved in the development of new relapses. Such B cell contribution to peripheral inflammation likely involves antibody-independent mechanisms. Of growing interest is the potential that B cells, within the MS central nervous system (CNS), may also contribute to the propagation of CNS-compartmentalized inflammation in progressive (non-relapsing) disease. B cells are known to persist in the inflamed MS CNS and are more recently described as concentrated in meningeal immune-cell aggregates, adjacent to the subpial cortical injury which has been associated with progressive disease. How B cells are fostered within the MS CNS and how they may contribute locally to the propagation of CNS-compartmentalized inflammation remain to be elucidated.
METHODS
We considered whether activated human astrocytes might contribute to B cell survival and function through soluble factors. B cells from healthy controls (HC) and untreated MS patients were exposed to primary human astrocytes that were either maintained under basal culture conditions (non-activated) or pre-activated with standard inflammatory signals. B cell exposure to astrocytes included direct co-culture, co-culture in transwells, or exposure to astrocyte-conditioned medium. Following the different exposures, B cell survival and expression of T cell co-stimulatory molecules were assessed by flow cytometry, as was the ability of differentially exposed B cells to induce activation of allogeneic T cells.
RESULTS
Secreted factors from both non-activated and activated human astrocytes robustly supported human B cell survival. Soluble products of pre-activated astrocytes also induced B cell upregulation of antigen-presenting cell machinery, and these B cells, in turn, were more efficient activators of T cells. Astrocyte-soluble factors could support survival and activation of B cell subsets implicated in MS, including memory B cells from patients with both relapsing and progressive forms of disease.
CONCLUSIONS
Our findings point to a potential mechanism whereby activated astrocytes in the inflamed MS CNS not only promote a B cell fostering environment, but also actively support the ability of B cells to contribute to the propagation of CNS-compartmentalized inflammation, now thought to play key roles in progressive disease.
Topics: Astrocytes; B-Lymphocytes; Cells, Cultured; Central Nervous System; Coculture Techniques; Cytokines; Female; Fetus; Flow Cytometry; Humans; Lymphocyte Activation; Male; Multiple Sclerosis; T-Lymphocytes
PubMed: 29673365
DOI: 10.1186/s12974-018-1136-2