Na+/H+ antiport and buffering capacity in human polymorphonuclear and mononuclear leucocytes

1991 ◽  
Vol 80 (2) ◽  
pp. 95-99 ◽  
Author(s):  
V. Frighi ◽  
L. L. Ng ◽  
A. Lewis ◽  
H. Dhar
Keyword(s):  
Intracellular Ph ◽  
Mononuclear Cells ◽  
Cell Types ◽  
Buffering Capacity ◽  
Polymorphonuclear Cells ◽  
Polymorphonuclear Leucocytes ◽  
Significant Difference ◽  
Mononuclear Leucocytes

1. Na+/H+ antiport activity was measured in peripheral blood polymorphonuclear and mononuclear cells of 12 healthy subjects by using an intracellular pH clamp technique to determine the external Na+-dependent H+ efflux rate in cells loaded with a pH-sensitive fluorescent dye, bis(carboxyethyl)carboxyfluorescein. The change in external Na+ concentrations for all pH measurements was similar in both cell types. 2. A significant difference between the two types of cells was found, the polymorphonuclear leucocytes having a higher Na+/H+ antiport activity than the lymphocytes. Cellular intrinsic buffering capacity measured in the absence of HCO−3 was also higher in the polymorphonuclear cells than in the lymphocytes. 3. These differences may be associated with a difference in the role of the Na+/H+ exchanger in these two types of cells, although in vivo the presence of HCO−3/Cl− exchangers may also contribute to intracellular pH homoeostasis.

Intracytoplasmic Concentration of GM-CSF and Intensity of the GM-CSF Membrane Receptor Are Significantly Higher in Proliferative Than in Dysplastic Variant of CMML and Could Explain the Higher In Vivo and In Vitro Growth Pattern.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2602-2602
Author(s):  
Francesco Onida ◽  
Servida Federica ◽  
Soligo Davide ◽  
Ricci Clara ◽  
Pasquini Maria Cristina ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Membrane Receptor ◽  
Cytokine Receptor ◽  
Biological Difference ◽  
Gm Csf ◽  
Significant Difference ◽  
Normal Controls

Abstract Chronic myelomonocytic leukemia (CMML) is a heterogeneous hematological malignancy, which has been included in a new category of MDS/MPD disorders in the last WHO classification of myeloid malignancies. An arbitrarily chosen leukocyte count has been proposed by the FAB group to differentiate between a “dysplastic” type (MD-CMML, with ≤12 x 109 WBC/L) and a “proliferative” type (MP-CMML, with >12 x 109 WBC/L) of CMML. However, apart from the WBC count, no biological difference has been identified to support distinction between these two disease-entities. Among factors that have been implicated in pathogenesis of CMML, GM-CSF produced by either autocrine or paracrine mechanisms has been shown to be a major growth determinant. In this study, peripheral blood samples from normal controls and from patients affected by proliferative and dysplastic variants of CMML were used to investigate expression of intracytoplasmic GM-CSF and expression of GM-CSF membrane receptor. Briefly, mononuclear cells (MNC) were isolated on Ficoll-Paque density gradient and cryopreserved in FCS 10% DMSO. In a first set of experiments samples from 5 healthy controls, 11 MP-CMML and 8 MD-CMML were thawed, permeabilized and stained with GM-CSF PE (Caltag) to evaluate expression of the intracytoplasmic cytokine by FACSCalibur flow cytometer (BD). Mean percentage of GM-CSF expression was 0.1 (range 0–0.5) in normal controls, 59.8 (range 14.5–90.7) in MP-CMML and 2.27 (range 0–9.3) in MD-CMML. The difference between MP and MD disease was statistically significant. To further investigate the possible role of GM-CSF cytokine in the pathogenesis of CMML, in a second set of experiments, MNC from 8 normal controls, 14 MP-CMML and 11 MD-CMML samples were thawed and stained with GM-CSFR (CD116 Pharmingen) and then with Goat Anti-Mouse FITC (BD) to evaluate the expression of the cytokine receptor. Mean percentage of expression of GM-CSFR was significantly higher in CMML samples (41.3, range 9.5–69) than in normal controls (20.3, range 16.4–27.3). No difference was detected between subtypes of MP-CMML and MD-CMML. When we considered median intensity of GM-CSFR expression, we observed a significantly higher values in MP-CMML than in MD-CMML (123.2 and 51.4, respectively), whereas no significant difference was detected between normal samples and MD-CMML. In this study, we also assessed "in vitro" spontaneous colony growth of PB-MNC from patients with both variants of CMML. The number of CFU-GM was higher in the MP-CMML than in MD-CMML (57 vs 17/5x10e5 cells plated) and a significant correlation with intracytoplasmic GM-CSF expression was observed (p <0.05). The higher levels of intracytoplasmic GM-CSF and the increased density of the cytokine receptor in MP-CMML suggest a possible role of GM-CSF in malignant cell proliferation of CMML patients. If our results will be confirmed, these findings could be utilized as a possible biological marker to distinguish proliferative and dysplastic variants of the disease. Further studies are warranted to investigate possible therapeutic applications.

scholarly journals Gastric Hyperplasia and Increased Proliferative Responses of Lymphocytes in Mice Lacking the COOH-terminal Ankyrin Domain of NF-κB2

1997 ◽  
Vol 186 (7) ◽  
pp. 999-1014 ◽  
Author(s):  
Hideaki Ishikawa ◽  
Daniel Carrasco ◽  
Estefania Claudio ◽  
Rolf-Peter Ryseck ◽  
Rodrigo Bravo
Keyword(s):  
T Cells ◽  
Lymphocyte Proliferation ◽  
Cytokine Production ◽  
Cell Types ◽  
Homozygous Deletion ◽  
Binding Activity ◽  
Activated T Cells ◽  
Physiological Relevance

The nfkb2 gene encodes the p100 precursor which produces the p52 protein after proteolytic cleavage of its COOH-terminal domain. Although the p52 product can act as an alternative subunit of NF-κB, the p100 precursor is believed to function as an inhibitor of Rel/NF-κB activity by cytoplasmic retention of Rel/NF-κB complexes, like other members of the IκB family. However, the physiological relevance of the p100 precursor as an IκB molecule has not been understood. To assess the role of the precursor in vivo, we generated, by gene targeting, mice lacking p100 but still containing a functional p52 protein. Mice with a homozygous deletion of the COOH-terminal ankyrin repeats of NF-κB2 (p100−/−) had marked gastric hyperplasia, resulting in early postnatal death. p100−/− animals also presented histopathological alterations of hematopoietic tissues, enlarged lymph nodes, increased lymphocyte proliferation in response to several stimuli, and enhanced cytokine production in activated T cells. Dramatic induction of nuclear κB–binding activity composed of p52-containing complexes was found in all tissues examined and also in stimulated lymphocytes. Thus, the p100 precursor is essential for the proper regulation of p52-containing Rel/NF-κB complexes in various cell types and its absence cannot be efficiently compensated for by other IκB proteins.

scholarly journals Glucose-dependent blood flow dynamics in murine pancreatic islets in vivo

2010 ◽  
Vol 298 (4) ◽  
pp. E807-E814 ◽  
Author(s):  
Lara R. Nyman ◽  
Eric Ford ◽  
Alvin C. Powers ◽  
David W. Piston
Keyword(s):  
Blood Flow ◽  
Blood Glucose ◽  
Pancreatic Islets ◽  
Fluorescent Protein ◽  
Yellow Fluorescent Protein ◽  
Cell Types ◽  
Β Cells ◽  
Islet Blood Flow ◽  
Significant Difference

Pancreatic islets are highly vascularized and arranged so that regions containing β-cells are distinct from those containing other cell types. Although islet blood flow has been studied extensively, little is known about the dynamics of islet blood flow during hypoglycemia or hyperglycemia. To investigate changes in islet blood flow as a function of blood glucose level, we clamped blood glucose sequentially at hyperglycemic (∼300 mg/dl or 16.8 mM) and hypoglycemic (∼50 mg/dl or 2.8 mM) levels while simultaneously imaging intraislet blood flow in mouse models that express green fluorescent protein in the β-cells or yellow fluorescent protein in the α-cells. Using line scanning confocal microscopy, in vivo blood flow was assayed after intravenous injection of fluorescent dextran or sulforhodamine-labeled red blood cells. Regardless of the sequence of hypoglycemia and hyperglycemia, islet blood flow is faster during hyperglycemia, and apparent blood volume is greater during hyperglycemia than during hypoglycemia. However, there is no change in the order of perfusion of different islet endocrine cell types in hypoglycemia compared with hyperglycemia, with the islet core of β-cells usually perfused first. In contrast to the results in islets, there was no significant difference in flow rate in the exocrine pancreas during hyperglycemia compared with hypoglycemia. These results indicate that glucose differentially regulates blood flow in the pancreatic islet vasculature independently of blood flow in the rest of the pancreas.

scholarly journals Enhanced plasminogen-activator production by leukocytes in the human and murine Chediak-Higashi syndrome

Blood ◽  
1985 ◽  
Vol 65 (5) ◽  
pp. 1275-1281 ◽  
Author(s):  
G de Saint Basile ◽  
A Fischer ◽  
MD Dautzenberg ◽  
A Durandy ◽  
F Le Deist ◽  
...  
Keyword(s):  
Plasminogen Activator ◽  
Mononuclear Cells ◽  
Chronic Phase ◽  
Polymorphonuclear Cells ◽  
Clotting Factors ◽  
Coagulation Abnormalities ◽  
Life Threatening ◽  
Coagulation Status ◽  
Chediak Higashi Syndrome

Abstract We have studied the coagulation status of eight patients with the Chediak-Higashi syndrome (CHS), both in the chronic and the accelerated phase of the disease. It has been shown that during the accelerated phase there are coagulation abnormalities. These abnormalities include a peripheral thrombocytopenia, minor alterations of liver clotting factors, and mainly a profound hypofibrinogenemia and hypoplasminogenemia, which cause life-threatening bleedings. These disorders are of complex origin, but a fibrinolytic process, possibly primary, appears to play a significant role, since the present evidence for intravascular coagulation is not definitive. The accelerated phase of the CHS is characterized by a visceral infiltration by macrophages and lymphocytes. Therefore, we have investigated the possible role of the macrophages in the fibrinolytic process. We have found an excessive plasminogen activator (PA) production by CHS mononuclear cells in the accelerated phase and to a lesser extent in the chronic phase, except in one patient in whom no anomaly was found. Single-cell studies revealed an increased number of PA-producing cells among the monocyte- macrophage lineage rather than a higher level of production per cell. Polymorphonuclear cells (PMN) from patients with CHS were also shown to contain more PA. Slight but significant abnormalities in PA production were observed in obligatory heterozygotes (five out of nine), indicating the inherited nature of the excessive PA production. Finally, an enhanced PA production was similarly demonstrated using beige mice macrophages. The exacerbated production of PA by macrophages in the accelerated phase of the CHS can account to some extent for the coagulation abnormalities that have been observed.

scholarly journals Enhanced plasminogen-activator production by leukocytes in the human and murine Chediak-Higashi syndrome

Blood ◽  
1985 ◽  
Vol 65 (5) ◽  
pp. 1275-1281
Author(s):  
G de Saint Basile ◽  
A Fischer ◽  
MD Dautzenberg ◽  
A Durandy ◽  
F Le Deist ◽  
...  
Keyword(s):  
Plasminogen Activator ◽  
Mononuclear Cells ◽  
Chronic Phase ◽  
Polymorphonuclear Cells ◽  
Clotting Factors ◽  
Coagulation Abnormalities ◽  
Life Threatening ◽  
Coagulation Status ◽  
Chediak Higashi Syndrome

We have studied the coagulation status of eight patients with the Chediak-Higashi syndrome (CHS), both in the chronic and the accelerated phase of the disease. It has been shown that during the accelerated phase there are coagulation abnormalities. These abnormalities include a peripheral thrombocytopenia, minor alterations of liver clotting factors, and mainly a profound hypofibrinogenemia and hypoplasminogenemia, which cause life-threatening bleedings. These disorders are of complex origin, but a fibrinolytic process, possibly primary, appears to play a significant role, since the present evidence for intravascular coagulation is not definitive. The accelerated phase of the CHS is characterized by a visceral infiltration by macrophages and lymphocytes. Therefore, we have investigated the possible role of the macrophages in the fibrinolytic process. We have found an excessive plasminogen activator (PA) production by CHS mononuclear cells in the accelerated phase and to a lesser extent in the chronic phase, except in one patient in whom no anomaly was found. Single-cell studies revealed an increased number of PA-producing cells among the monocyte- macrophage lineage rather than a higher level of production per cell. Polymorphonuclear cells (PMN) from patients with CHS were also shown to contain more PA. Slight but significant abnormalities in PA production were observed in obligatory heterozygotes (five out of nine), indicating the inherited nature of the excessive PA production. Finally, an enhanced PA production was similarly demonstrated using beige mice macrophages. The exacerbated production of PA by macrophages in the accelerated phase of the CHS can account to some extent for the coagulation abnormalities that have been observed.

scholarly journals Il6/Sil6R Regulates Tnfα-Inflammatory Response In Synovial Fibroblasts Through Modulation of Transcriptional and Post-Transcriptional Mechanisms

2020 ◽  
Author(s):  
Alvaro Valin ◽  
Manuel J. Del Rey ◽  
Cristina Municio ◽  
Alicia Usategui ◽  
Marina Romero ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Mononuclear Cells ◽  
De Novo ◽  
Inflammatory Cells ◽  
Synovial Fibroblasts ◽  
Matrix Metalloproteases ◽  
P Value ◽  
Polymorphonuclear Cells ◽  
Expression Of Genes

Abstract Introduction: The clinical efficacy of specific interleukin-6 inhibitors has confirmed the central role of IL6 in rheumatoid arthritis (RA). However the local role of IL6, in particular in synovial fibroblasts (SF) as a direct cellular target to IL6/sIL6R signal is not well characterized. The purpose of the study was to characterize the crosstalk between TNFα and IL6/sIL6R signaling to the effector pro-inflammatory response of SF. Methods SF lines were stimulated with either TNFα or IL6 and sIL6R for the time and dose indicated for each experiment, and where indicated, cells were treated with inhibitors actinomycin D, adalimumab, ruxolitinib and cicloheximide. mRNA expression of cytokines, chemokines and matrix metalloproteases (MMPs) were analyzed by quantitative RT-PCR. Level of IL8 and CCL8 in culture supernatants was measured by ELISA. Mononuclear and polymorphonuclear cells migration assays were assesed by transwell using conditioned medium from SF cultures. Statistical analyses were performed as indicated in the corresponding figure legends and a p-value < 0.05 was considered statistically significant. Results IL6/sIL6R stimulation of TNFα treated SF cooperatively promotes the expression of mono- and lymphocytic chemokines such as IL6, CCL8 and CCL2, as well as matrix degrading enzymes such as MMP1, while inhibiting the induction of central neutrophil chemokines such as IL8. These changes in the pattern of chemokines expression resulted in reduced polymorphonuclear (PMN) and increased mononuclear cells (MNC) chemoattraction by SF. Mechanistic analyses of the temporal expression of genes demonstrated that the cooperative regulation mediated by these two factors is mostly induced through de novo transcriptional mechanisms activated by IL6/sIL6R. Furthermore, we also demonstrate that TNFα and IL6/sIL6R cooperation is partially mediated by the expression of secondary factors signaling through JAK/STAT pathways. Conclusions These results point out to a highly orchestrated response to IL6 in TNFα-induced SF and provide additional insights into the role of IL6/sIL6R in the context of RA, highlighting the contribution of IL6/sIL6R to the interplay of SF with other inflammatory cells.

scholarly journals The critical immunosuppressive effect of MDSC-derived exosomes in the tumor microenvironment

2020 ◽  
Author(s):  
Mohammad H. Rashid ◽  
Thaiz F. Borin ◽  
Roxan Ara ◽  
Raziye Piranlioglu ◽  
Bhagelu R. Achyut ◽  
...  
Keyword(s):  
T Cells ◽  
Tumor Microenvironment ◽  
Tumor Growth ◽  
Cd8 T Cells ◽  
Suppressor Cells ◽  
Cell Types ◽  
Biological Macromolecules

AbstractMyeloid-derived suppressor cells (MDSCs) are an indispensable component of the tumor microenvironment (TME), and our perception regarding the role of MDSCs in tumor promotion is attaining extra layer of intricacy in every study. In conjunction with MDSC’s immunosuppressive and anti-tumor immunity, they candidly facilitate tumor growth, differentiation, and metastasis in several ways that yet to be explored. Alike any other cell types, MDSCs also release a tremendous amount of exosomes or nanovesicles of endosomal origin and partake in intercellular communications by dispatching biological macromolecules. There has not been any experimental study done to characterize the role of MDSCs derived exosomes (MDSC exo) in the modulation of TME. In this study, we isolated MDSC exo and demonstrated that they carry a significant amount of proteins that play an indispensable role in tumor growth, invasion, angiogenesis, and immunomodulation. We observed higher yield and more substantial immunosuppressive potential of exosomes isolated from MDSCs in the primary tumor area than those are in the spleen or bone marrow. Our in vitro data suggest that MDSC exo are capable of hyper activating or exhausting CD8 T-cells and induce reactive oxygen species production that elicits activation-induced cell death. We confirmed the depletion of CD8 T-cells in vivo by treating the mice with MDSC exo. We also observed a reduction in pro-inflammatory M1-macrophages in the spleen of those animals. Our results indicate that immunosuppressive and tumor-promoting functions of MDSC are also implemented by MDSC-derived exosomes which would open up a new avenue of MDSC research and MDSC-targeted therapy.

scholarly journals Inhibition of mTOR during a postnatal critical sensitive window rescues deficits in GABAergic PV cell connectivity and social behavior caused by loss of TSC1

2020 ◽  
Author(s):  
Mayukh Choudhury ◽  
Clara A. Amegandjin ◽  
Vidya Jadhav ◽  
Josianne Nunes Carriço ◽  
Ariane Quintal ◽  
...  
Keyword(s):  
Social Behavior ◽  
Time Course ◽  
Cell Types ◽  
Developmental Time ◽  
Adult Mice ◽  
Mtorc1 Signaling ◽  
Pv Cell ◽  
Mechanistic Basis

ABSTRACTMutations in regulators of the Mechanistic Target Of Rapamycin Complex 1 (mTORC1), such as Tsc1/2, lead to neurodevelopmental disorders associated with autism, intellectual disabilities and epilepsy. Whereas the effects of mTORC1 signaling dysfunction within diverse cell types are likely critical for the onset of the diverse neurological symptoms associated with mutations in mTORC1 regulators, they are not well understood. In particular, the effects of mTORC1 dys-regulation in specific types of inhibitory interneurons are unclear.Here, we showed that Tsc1 haploinsufficiency in parvalbumin (PV)-positive GABAergic interneurons either in cortical organotypic cultures or in vivo caused a premature increase in their perisomatic innervations, followed by a striking loss in adult mice. This effects were accompanied by alterations of AMPK-dependent autophagy in pre-adolescent but not adult mice. PV cell-restricted Tsc1 mutant mice showed deficits in social behavior. Treatment with the mTOR inhibitor Rapamycin restricted to the third postnatal week was sufficient to permanently rescue deficits in both PV cell innervation and social behavior in adult conditional haploinsufficient mice. All together, these findings identify a novel role of Tsc1-mTORC1 signaling in the regulation of the developmental time course and maintenance of cortical PV cell connectivity and provide a mechanistic basis for the targeted rescue of autism-related behaviors in disorders associated with deregulated mTORC1 signaling.

scholarly journals Revisiting the role of IRF3 in inflammation and immunity by conditional and specifically targeted gene ablation in mice

2018 ◽  
Vol 115 (20) ◽  
pp. 5253-5258 ◽  
Author(s):  
Hideyuki Yanai ◽  
Shiho Chiba ◽  
Sho Hangai ◽  
Kohei Kometani ◽  
Asuka Inoue ◽  
...  
Keyword(s):  
Immune Cell ◽  
Cell Types ◽  
Type I ◽  
Type I Ifn ◽  
Cell Type ◽  
Gene Ablation ◽  
Cell Type Specific

IFN regulatory factor 3 (IRF3) is a transcription regulator of cellular responses in many cell types that is known to be essential for innate immunity. To confirm IRF3’s broad role in immunity and to more fully discern its role in various cellular subsets, we engineered Irf3-floxed mice to allow for the cell type-specific ablation of Irf3. Analysis of these mice confirmed the general requirement of IRF3 for the evocation of type I IFN responses in vitro and in vivo. Furthermore, immune cell ontogeny and frequencies of immune cell types were unaffected when Irf3 was selectively inactivated in either T cells or B cells in the mice. Interestingly, in a model of lipopolysaccharide-induced septic shock, selective Irf3 deficiency in myeloid cells led to reduced levels of type I IFN in the sera and increased survival of these mice, indicating the myeloid-specific, pathogenic role of the Toll-like receptor 4–IRF3 type I IFN axis in this model of sepsis. Thus, Irf3-floxed mice can serve as useful tool for further exploring the cell type-specific functions of this transcription factor.

Abstract 135: Exploration and Modulation of TREM-1 in Experimental Atherosclerosis

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Stephane Potteaux ◽  
Jeremie Joffre ◽  
Bruno Esposito ◽  
Alain Tedgui ◽  
Sebastien Gibot ◽  
...  
Keyword(s):  
Cell Types ◽  
Experimental Atherosclerosis ◽  
Soluble Form ◽  
Daily Injection ◽  
Preferential Expression ◽  
Monocyte Migration ◽  
Plaque Development ◽  
Blood Neutrophils

Under conditions of atherosclerosis, monocytes are rapidely recruited into the vessel wall where they differentiate into macrophages. Both classical and nonclassical monocytes are continuously recruited to the lesion and contribute to atherosclerosis formation. Whereas the number of circulating monocytes correlates with plaque development, decrease in their number or migration is protective. Upon differentiation, macrophages increase TLR expression, which triggers the inflammatory response. The triggering receptor expressed on myeloid cells (TREM-1) has been shown to amplify TLR-induced signals in sepsis or inflammatory bowel disease. TREM-1 is also produced in a soluble form and is a predictive factor during sever infections in humans. We addressed for the first time the role of TREM-1 in atherosclerosis. We found preferential expression of TREM-1 on blood neutrophils and nonclassical monocytes in both ApoE+/+ and ApoE-/- mice, but sTREM-1 was only detectable in plasma of ApoE-/- mice (ELISA). TREM-1 expression was significantly increased on both cell types in APOE-/- mice after 4 weeks of high fat diet (Flow cytometry). We next addressed the role of TREM-1 in atherosclerosis formation by injection of a TREM-like transcript 1-derived peptide (LR12) in 8 week-old ApoE-/- mice (daily injection for 4 weeks of LR12 or peptide scramble as control). We found that pharmaceutical inhibition of TREM-1 significantly reduced plaque formation by 30% without change in cholesterol levels. This was associated with significant reduction in macrophage accumulation after treatment with LR12 (57735,34 μm2 vs 78398,38 μm2 in controls; p=0,004). We demonstrated that LR12 treatment induced a specific rapid and sustained decrease in circulating nonclassical monocytes after 7 days of treatment. By using an in vivo pulse labeling method to quantify monocyte migration, we found that LR12 also altered nonclassical monocyte recruitment to the plaque. Taken together, these data indicate that TREM-1 expression increases in the context of atherosclerosis and that pharmacological inhibition of TREM-1 protects against plaque development through decreased number and infiltration of nonclassical monocytes.

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