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PloS One 2022Vitamin D deficiency is common among postmenopausal women. Telomere length can be a potential protective mechanism for age-related diseases. The objective of our study... (Randomized Controlled Trial)
Randomized Controlled Trial
Vitamin D deficiency is common among postmenopausal women. Telomere length can be a potential protective mechanism for age-related diseases. The objective of our study is to examine the association of vitamin D supplementation on leukocyte telomere length (LTL) in healthy postmenopausal women with vitamin D deficiency. The study was designed as a placebo-controlled study to investigate the short-term effects of vitamin D supplementation and seasonal changes on vitamin D related parameters, including 25(OH)D, 1,25(OH)2D parathormone (PTH), Vitamin D binding protein (VDBP), vitamin D receptor (VDR), and telomere length in a cohort of postmenopausal women (n = 102). The group was divided as supplementation (n = 52) and placebo groups (n = 50). All parameters were measured before and after treatment. Serum VDBP levels were measured by ELISA method and VDR, GC (VDBP) gene expressions and relative telomere lengths were measured in peripheral blood mononuclear cells (PBMC) using a quantitative real-time PCR method. The results demonstrate that baseline levels were similar between the groups. After vitamin D supplementation 25(OH)D, 1,25(OH)2D, PTH and VDBP levels were changed significantly compared to the placebo group. At the end of the study period, LTL levels were significantly increased in both groups and this change was more prominent in placebo group. The change in GC expression was significant between treatment and placebo groups but VDR expression remained unchanged. Even though the study was designed to solely assess the effects of vitamin D supplementation, LTL was significantly increased in the whole study group in summer months suggesting that LTL levels are affected by sun exposure and seasonal changes rather than supplementation. The study displayed the short-term effect of Vitamin D supplementation on vitamin D, PTH levels, LTL and vitamin D associated gene expressions. The relation between Vitamin D and LTL is not linear and could be confounded by several factors such as the population differences, regional and seasonal changes in sun exposure.
Topics: Aged; Cohort Studies; Female; Humans; Leukocytes, Mononuclear; Middle Aged; Postmenopause; Receptors, Calcitriol; Telomere; Telomere Homeostasis; Transcriptome; Vitamin D; Vitamin D Deficiency
PubMed: 35202418
DOI: 10.1371/journal.pone.0264337 -
Journal of Dairy Science Nov 2003Effects of increased dietary energy and protein on the composition and functional capacities of blood mononuclear leukocyte populations from milk replacer-fed calves...
Effects of increased dietary energy and protein on the composition and functional capacities of blood mononuclear leukocyte populations from milk replacer-fed calves were investigated. Holstein bull calves (average age: 4.2 d; n = 19) were assigned randomly to one of two treatment groups. Treatment 1 calves (n = 9) were fed a 20% crude protein, 20% fat milk replacer at a rate of 1.4% body weight of dry matter/d for 8 wk, whereas treatment 2 calves (n = 10) were fed a 30% crude protein, 20% fat milk replacer at a rate of 2.5% body weight of dry matter per day. Composition and functional capacities of mononuclear leukocyte populations from blood samples collected at 4, 18, 32, 46, and 60 d of age were characterized by flow cytometry and ex vivo cell function assays. From 11 to 60 d of age, the mean daily weight gain of treatment 2 calves (1.20 kg/d) was greater than daily weight gain of treatment 1 calves (0.55 kg/d). At 60 d of age, the mean body weight of treatment two calves was 53% (39 kg) greater than the mean body weight of treatment 1 calves. Total numbers of blood leukocytes and the composition of the mononuclear leukocyte population were unaffected by the plane of nutrition. Mitogen-induced DNA-synthesis and immunoglobulin M secretion also were unaffected by dietary treatment. Blood mononuclear leukocytes from calves on intensified diets, however, produced less interferon-gamma and more inducible nitric oxide, suggesting that increased dietary energy and protein affects specific aspects of leukocyte function associated with cell-mediated immunity. The impact of altered interferon-gamma and NO production on the calf s susceptibility to infectious disease are not known. Mononuclear leukocyte populations from all calves also demonstrated age-related changes in composition and functional capacity, likely reflecting natural exposure to infectious agents and maturation of the calfs immune system.
Topics: Aging; Animals; Animals, Newborn; Cattle; Dietary Fats; Dietary Proteins; Flow Cytometry; Food, Formulated; Immunity, Cellular; Leukocytes, Mononuclear; Male; Random Allocation; Weight Gain
PubMed: 14672190
DOI: 10.3168/jds.S0022-0302(03)73965-4 -
Blood Purification 2023Uremic retention solutes have been alleged to induce the apoptotic program of different cell types, including peripheral blood mononuclear leukocytes (PBL), which may...
INTRODUCTION
Uremic retention solutes have been alleged to induce the apoptotic program of different cell types, including peripheral blood mononuclear leukocytes (PBL), which may contribute to uremic leukopenia and immune dysfunction.
METHODS
The molecular effects of these solutes were investigated in uremic PBL (u-PBL) and mononuclear cell lines (THP-1 and K562) exposed to the high molecular weight fraction of uremic plasma (u-HMW) prepared by in vitro ultrafiltration with 50 kDa cut-off microconcentrators.
RESULTS
u-PBL show reduced cell viability and increased apoptotic death compared to healthy control PBL (c-PBL). u-HMW induce apoptosis both in u-PBL and c-PBL, as well as in mononuclear cell lines, also stimulating cellular H2O2 formation and secretion, IRE1-α-mediated endoplasmic reticulum stress signaling, and JNK/cJun pathway activation. Also, u-HMW induce autophagy in THP-1 monocytes. u-PBL were characterized by the presence in their cellular proteome of the main proteins and carbonylation targets of u-HMW, namely albumin, transferrin, and fibrinogen, and by the increased expression of receptor for advanced glycation end-products, a scavenger receptor with promiscuous ligand binding properties involved in leukocyte activation and endocytosis.
CONCLUSIONS
Large uremic solutes induce abnormal endocytosis and terminal alteration of cellular proteostasis mechanisms in PBL, including UPR/ER stress response and autophagy, ultimately activating the JNK-mediated apoptotic signaling of these cells. These findings describe the suicidal role of immune cells in facing systemic proteostasis alterations of kidney disease patients, a process that we define as the immuno-proteostasis response of uremia.
Topics: Humans; Leukocytes, Mononuclear; Proteostasis; Receptor for Advanced Glycation End Products; Hydrogen Peroxide; Proteins; Apoptosis
PubMed: 37703866
DOI: 10.1159/000533309 -
Kidney International. Supplement Feb 2001Circulating blood leukocytes have short life expectancies and end their lives by committing programmed cell death or apoptosis. Apoptosis is an active form of cell death... (Review)
Review
Circulating blood leukocytes have short life expectancies and end their lives by committing programmed cell death or apoptosis. Apoptosis is an active form of cell death that is initiated by a number of stimuli and is intricately regulated. Apoptosis in both excessive and reduced amounts has pathological implications. Evidence suggests that apoptosis may play a role in the pathophysiology of immune dysfunction in uremia. Indeed, accelerated programmed cell death has been observed in lymphocytes, monocytes, and polymorphonuclear leukocytes among patients with chronic renal failure. This may be due in part to the retention of uremic toxins. The aim of this article is to review the evidence for accelerated leukocyte apoptosis, key regulatory apoptotic pathways, and the possible role of this highly organized process in the pathogenesis of immune dysfunction in uremia.
Topics: Apoptosis; Caspases; Humans; Immunity, Cellular; Kidneys, Artificial; Leukocytes; Leukocytes, Mononuclear; Neutrophils; Oxidative Stress; Peritoneal Dialysis; Proto-Oncogene Proteins c-bcl-2; Toxins, Biological; Uremia; fas Receptor
PubMed: 11169011
DOI: 10.1046/j.1523-1755.2001.59780197.x -
Investigative Ophthalmology & Visual... Oct 2023Eye inflammation may occur in patients with inherited retinal dystrophies (IRDs) and is seen frequently in IRDs associated with mutations in the CRB1 gene. The purpose...
PURPOSE
Eye inflammation may occur in patients with inherited retinal dystrophies (IRDs) and is seen frequently in IRDs associated with mutations in the CRB1 gene. The purpose of this study was to determine the types of inflammatory cells involved in IRDs, by deep profiling the composition of peripheral blood mononuclear cells of patients with a CRB1-associated IRD.
METHODS
This study included 33 patients with an IRD with confirmed CRB1 mutations and 32 healthy controls. A 43-parameter flow cytometry analysis was performed on peripheral blood mononuclear cells isolated from venous blood. FlowSOM and manual Boolean combination gating were used to identify and quantify immune cell subsets.
RESULTS
Comparing patients with controls revealed a significant increase in patients in the abundance of circulating CD4+ T cells and CD8+ T cells that express sialyl Lewis X antigen. Furthermore, we detected a decrease in plasmacytoid dendritic cells and an IgA+CD24+CD38+ transitional B-cell subset in patients with an IRD.
CONCLUSIONS
Patients with a CRB1-associated IRD show marked changes in blood leukocyte composition, affecting lymphocyte and dendritic cell populations. These results implicate inflammatory pathways in the disease manifestations of IRDs.
Topics: Humans; Leukocytes, Mononuclear; Eye Proteins; Retinal Dystrophies; Mutation; Eye Abnormalities; T-Lymphocytes; Membrane Proteins; Nerve Tissue Proteins
PubMed: 37792335
DOI: 10.1167/iovs.64.13.6 -
Scientific Reports Nov 2016Interactions between endothelial selectins and the leukocyte counter-receptor PSGL1 mediates leukocyte recruitment to inflammation sites. PSGL1 is highly sialylated,...
Interactions between endothelial selectins and the leukocyte counter-receptor PSGL1 mediates leukocyte recruitment to inflammation sites. PSGL1 is highly sialylated, making it a potential ligand for Siglec-5, a leukocyte-receptor that recognizes sialic acid structures. Binding assays using soluble Siglec-5 variants (sSiglec-5/C4BP and sSiglec-5/Fc) revealed a dose- and calcium-dependent binding to PSGL1. Pre-treatment of PSGL1 with sialidase reduced Siglec-5 binding by 79 ± 4%. In confocal immune-fluorescence assays, we observed that 50% of Peripheral Blood Mononuclear Cells (PBMCs) simultaneously express PSGL1 and Siglec-5. Duolink-proximity ligation analysis demonstrated that PSGL1 and Siglec-5 are in close proximity (<40 nm) in 31 ± 4% of PBMCs. In vitro perfusion assays revealed that leukocyte-rolling over E- and P-selectin was inhibited by sSiglec-5/Fc or sSiglec-5/C4BP, while adhesion onto VCAM1 was unaffected. When applied to healthy mice (0.8 mg/kg), sSiglec-5/C4BP significantly reduced the number of rolling leukocytes under basal conditions (10.9 ± 3.7 versus 23.5 ± 9.3 leukocytes/field/min for sSiglec-5/C4BP-treated and control mice, respectively; p = 0.0093). Moreover, leukocyte recruitment was inhibited over a 5-h observation period in an in vivo model of TNFalpha-induced inflammation following injection sSiglec-5/C4BP (0.8 mg/kg). Our data identify PSGL1 as a ligand for Siglec-5, and soluble Siglec-5 variants appear efficient in blocking PSGL1-mediated leukocyte rolling and the inflammatory response in general.
Topics: Animals; Anti-Inflammatory Agents; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Disease Models, Animal; E-Selectin; Female; Humans; Inflammation; Lectins; Leukocyte Rolling; Leukocytes, Mononuclear; Membrane Glycoproteins; Mice, Inbred C57BL; P-Selectin; Protein Interaction Domains and Motifs; Solubility; Tumor Necrosis Factor-alpha
PubMed: 27892504
DOI: 10.1038/srep37953 -
Scientific Reports May 2021Early life stress increases one's risk for health problems later in life, and many studies find that these effects are sex-differentiated. Here, we examined... (Observational Study)
Observational Study
Early life stress increases one's risk for health problems later in life, and many studies find that these effects are sex-differentiated. Here, we examined relationships between multiple sources of early life stress and adult immune function in humans across several functional assays. Adult participants provided retrospective information about their childhood (a) socioeconomic status, (b) household unpredictability, and (c) exposure to adverse experiences. Participants' peripheral blood mononuclear cells (PBMCs) were then isolated for use in functional assays of immune performance: (a) tumor cell lysis by natural killer cells, (b) phagocytosis of Escherichia coli bioparticles, and (c) mitogen-induced leukocyte proliferation and cytokine release. In men, lower childhood socioeconomic status predicted decrements in immunological performance across functional assays, along with greater spontaneous cytokine release from PBMCs. These changes co-occurred with elevations in plasma testosterone levels. Similar effects were not observed for other sources of stress, nor were they found in women (with the exception of spontaneous cytokine release). These findings provide evidence that low childhood socioeconomic status has a lasting negative impact on multiple aspects of immune function, particularly in men.
Topics: Adolescent; Adverse Childhood Experiences; Cell Proliferation; Cytokines; Female; Humans; Immunity; Immunoassay; Killer Cells, Natural; Leukocytes, Mononuclear; Male; Sex Factors; Social Class; Young Adult
PubMed: 33972662
DOI: 10.1038/s41598-021-89413-y -
STAR Protocols Dec 2021Deep immune profiling is essential for understanding the human immune system in health and disease. Successful biological interpretation of this data requires consistent...
Deep immune profiling is essential for understanding the human immune system in health and disease. Successful biological interpretation of this data requires consistent laboratory processing with minimal batch-to-batch variation. Here, we detail a robust pipeline for the profiling of human peripheral blood mononuclear cells by both high-dimensional flow cytometry and single-cell RNA-seq. These protocols reduce batch effects, generate reproducible data, and increase throughput. For complete details on the use and execution of this protocol, please refer to Savage et al. (2021).
Topics: Computational Biology; Flow Cytometry; Humans; Leukocytes, Mononuclear; Monitoring, Immunologic; Sequence Analysis, RNA; Single-Cell Analysis
PubMed: 34806044
DOI: 10.1016/j.xpro.2021.100900 -
Journal of Dairy Science Mar 1988In vitro effects of killed Staphylococcus aureus cells on bovine blood mononuclear leukocytes from uninfected cows or cows with chronic staphylococcal mastitis were...
In vitro effects of killed Staphylococcus aureus cells on bovine blood mononuclear leukocytes from uninfected cows or cows with chronic staphylococcal mastitis were assessed using a lymphocyte proliferation assay and a [51Cr] release cytotoxicity assay. Killed S. aureus cells cultured with mononuclear leukocytes caused a concentration-dependent decrease in lymphocyte proliferation that was associated with a concomitant decrease in mononuclear leukocyte viability. Responses of mononuclear leukocytes from uninfected and infected cows to killed S. aureus were similar, indicating effects were independent of the infection status of the animal. Addition of blood polymorphonuclear leukocytes to blood mononuclear leukocyte cultures without S. aureus cells did not alter mononuclear leukocyte viability but suppressed lymphocyte proliferation at the highest polymorphonuclear leukocyte:mononuclear leukocyte ratios (4:1 and 8:1) tested. When S. aureus cells and polymorphonuclear leukocytes were cultured with mononuclear leukocytes, both blood and milk polymorphonuclear leukocytes protected against the loss of viability compared with leukocytes cultured with S. aureus cells alone but did not consistently restore proliferative responses of the lymphocytes. These observations demonstrate that lymphocyte proliferation and mononuclear leukocyte viability are detrimentally affected by S. aureus cells, an effect that can be modulated by blood or milk polymorphonuclear leukocytes.
Topics: Animals; Cattle; Female; In Vitro Techniques; Leukocytes, Mononuclear; Lymphocyte Activation; Mastitis, Bovine; Neutrophils; Staphylococcal Infections; Staphylococcus aureus
PubMed: 3372823
DOI: 10.3168/jds.S0022-0302(88)79624-1 -
Cytometry. Part a : the Journal of the... Oct 2015The blood-brain barrier (BBB) is primarily comprised of brain microvascular endothelial cells (BMVEC) and astrocytes and serves as a physical and chemical barrier that...
The blood-brain barrier (BBB) is primarily comprised of brain microvascular endothelial cells (BMVEC) and astrocytes and serves as a physical and chemical barrier that separates the periphery from the brain. We describe a flow cytometric method using our in vitro model of the human BBB to characterize BMVEC surface junctional proteins critical for maintenance of barrier function, cell viability, and leukocyte adhesion. For this methodology, BMVEC are cocultured with astrocytes in a transwell tissue culture insert to establish the barrier, after which time the BBB are treated with specific agents, and the BMVEC collected for flow cytometric analyses. We use a standard and optimized method to recover the BMVEC from the coculture model that maintains junctional protein expression and cell viability. A novel leukocyte adhesion assay enables a quantitative analysis of peripheral blood mononuclear cell (PBMC) interactions with the BMVEC and can be used to assess the adhesion of many cell types to the BBB. Furthermore, this method enables the concomitant analysis of a large number of adhesion molecules and tight junction proteins on both the BMVEC and adherent PBMC under homeostatic and pathologic conditions. Flow cytometry is an extremely powerful tool, and this technique can also be applied to assess variables not performed in this study, including cell cycle progression, and calcium flux.
Topics: Astrocytes; Blood-Brain Barrier; Brain; Cell Adhesion; Cell Differentiation; Endothelial Cells; Flow Cytometry; Humans; Leukocytes, Mononuclear
PubMed: 25929817
DOI: 10.1002/cyto.a.22683