scholarly journals Differences in flow cytometry and 3H-thymidine analyses of perturbed human lymphocytes.

1979 ◽  
Vol 27 (1) ◽  
pp. 486-490 ◽  
Author(s):  
A Pollack ◽  
C B Bagwell ◽  
J L Hudson ◽  
G L Irvin
Keyword(s):  
Flow Cytometry ◽  
Dna Synthesis ◽  
Human Peripheral Blood ◽  
Tritiated Thymidine ◽  
Human Lymphocytes ◽  
Flow Cytometric Analysis ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Peripheral Blood Lymphocytes ◽  
Inhibition Of Dna Synthesis

A calf thymocyte crude aqueous extract was tested for DNA synthesis inhibitory activity using phytohemagglutinin-stimulated human peripheral blood lymphocytes. Inhibition of DNA synthesis was assayed using tritiated thymidine and flow cytometry. Although the calf thymocyte crude extract inhibited tritiated thymidine incorporation by over 50%, only very slight changes in the flow cytometric analysis were observed. When dibutyryl-cyclic adenosine monophosphate was used as an inhibitor, a correlation in terms of the inhibition of tritiated thymidine to the inhibition by flow cytometry was observed.

scholarly journals Regulation of human monocyte DNA synthesis by colony-stimulating factors, cytokines, and cyclic adenosine monophosphate

Blood ◽  
1992 ◽  
Vol 79 (8) ◽  
pp. 1972-1981 ◽  
Author(s):  
DL Cheung ◽  
JA Hamilton
Keyword(s):  
Dna Synthesis ◽  
Human Peripheral Blood ◽  
Cyclic Adenosine Monophosphate ◽  
Human Monocyte ◽  
Adenosine Monophosphate ◽  
Interleukin 4 ◽  
Murine Macrophage ◽  
Colony Stimulating Factor ◽  
Gm Csf ◽  
Stimulating Factor

Abstract It is reported in this study that a subpopulation of highly purified human peripheral blood human monocytes can proliferate in response to colony-stimulating factor-1 (CSF-1), granulocyte-macrophage colony- stimulating factor (GM-CSF), and interleukin-3 (IL-3). Both GM-CSF and IL-3 synergized with CSF-1 for the induction of DNA synthesis. Given the DNA synthesis levels attained, we were able to test the effects of certain cytokines and cyclic adenosine monophosphate (cAMP)-elevating agents, which have been shown to modulate in vitro human myelopoiesis and murine macrophage proliferation. The cytokines, interferon-gamma (IFN-gamma), interleukin-4 (IL-4), and tumor necrosis factor-alpha (TNF- alpha), as well as cAMP-elevating agents, 8-bromoadenosine 3′:5′-cyclic monophosphate (8BrcAMP), cholera toxin (CT), and prostaglandin E2 (PGE2), suppressed the monocyte DNA synthesis due to CSF-1. These results parallel those reported with human bone marrow progenitors, as well as murine macrophage populations. The cycling human monocyte population could provide a model cell type to understand the molecular events controlling human myelopoiesis.

scholarly journals Suppression of the formation of polyamines and macromolecules by dl-α-difluoromethylornithine and methylglyoxal bis(guanylhydrazone) in phytohaemagglutinin-activated human lymphocytes

1979 ◽  
Vol 178 (1) ◽  
pp. 109-117 ◽  
Author(s):  
Juhani Jänne ◽  
Tapani Hovi ◽  
Erkki Hölttä
Keyword(s):  
Protein Synthesis ◽  
Dna Synthesis ◽  
Human Peripheral Blood ◽  
Human Lymphocytes ◽  
Peripheral Blood Lymphocytes ◽  
Irreversible Inhibitor ◽  
Polyamine Biosynthesis ◽  
Inhibition Of Protein Synthesis ◽  
Dose Dependent Decrease

1. The activation of human peripheral blood lymphocytes by phytohaemagglutinin in vitro was accompanied by striking increases in the concentrations of the natural polyamines putrescine, spermidine and spermine. 2. The enhanced accumulation of polyamines could be almost totally abolished by dl-α-difluoromethylornithine, a newly discovered irreversible inhibitor of l-ornithine decarboxylase (EC 4.1.1.17), or by methylglyoxal bis(guanylhydrazone) {1,1′-[(methylethanediylidene)dinitrilo]diguanidine}, an inhibitor of S-adenosyl-l-methionine decarboxylase (EC 4.1.1.50). The inhibition of polyamine accumulation was associated with a marked suppression of DNA synthesis, which was partially or totally reversed by low concentrations of exogenous putrescine, spermidine, spermine and cadaverine and by higher concentrations of 1,3-diaminopropane. 3. In contrast with some earlier studies, we found that methylglyoxal bis(guanylhydrazone), at concentrations that were sufficient to prevent polyamine accumulation, also caused a clear inhibition of protein synthesis in the activated lymphocytes. Similar results were obtained with difluoromethylornithine. The decrease in protein synthesis caused by both compounds preceded the impairment of DNA synthesis. The inhibition of protein synthesis by difluoromethylornithine was fully reversed by exogenous putrescine, spermidine and spermine, and that caused by methylglyoxal bis(guanylhydrazone) by spermidine and spermine. In further support of the idea that the inhibition of protein synthesis by these compounds was related to the polyamine depletion, we found that difluoromethylornithine caused a dose-dependent decrease in the incorporation of [14C]leucine into lymphocyte proteins which closely correlated with the decreased concentrations of cellular spermidine. 4. Difluoromethylornithine and methylglyoxal bis(guanylhydrazone) also elicited a variable depression in the incorporation of [3H]uridine and [14C]adenine into total RNA. The apparent turnover of lymphocyte RNA remained essentially unchanged in spite of severe polyamine depletion brought about by difluoromethylornithine. 5. The present results, as well as confirming the anti-proliferative action of the inhibitors of polyamine biosynthesis, suggest that polyamine depletion may interfere with reactions at different levels of gene expression.

scholarly journals Regulation of human monocyte DNA synthesis by colony-stimulating factors, cytokines, and cyclic adenosine monophosphate

Blood ◽  
1992 ◽  
Vol 79 (8) ◽  
pp. 1972-1981
Author(s):  
DL Cheung ◽  
JA Hamilton
Keyword(s):  
Dna Synthesis ◽  
Human Peripheral Blood ◽  
Cyclic Adenosine Monophosphate ◽  
Human Monocyte ◽  
Adenosine Monophosphate ◽  
Interleukin 4 ◽  
Murine Macrophage ◽  
Colony Stimulating Factor ◽  
Gm Csf ◽  
Stimulating Factor

It is reported in this study that a subpopulation of highly purified human peripheral blood human monocytes can proliferate in response to colony-stimulating factor-1 (CSF-1), granulocyte-macrophage colony- stimulating factor (GM-CSF), and interleukin-3 (IL-3). Both GM-CSF and IL-3 synergized with CSF-1 for the induction of DNA synthesis. Given the DNA synthesis levels attained, we were able to test the effects of certain cytokines and cyclic adenosine monophosphate (cAMP)-elevating agents, which have been shown to modulate in vitro human myelopoiesis and murine macrophage proliferation. The cytokines, interferon-gamma (IFN-gamma), interleukin-4 (IL-4), and tumor necrosis factor-alpha (TNF- alpha), as well as cAMP-elevating agents, 8-bromoadenosine 3′:5′-cyclic monophosphate (8BrcAMP), cholera toxin (CT), and prostaglandin E2 (PGE2), suppressed the monocyte DNA synthesis due to CSF-1. These results parallel those reported with human bone marrow progenitors, as well as murine macrophage populations. The cycling human monocyte population could provide a model cell type to understand the molecular events controlling human myelopoiesis.

scholarly journals Investigation of the Immune Modulatory Potential of Zinc Oxide Nanoparticles in Human Lymphocytes

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 629
Author(s):  
Helena Moratin ◽  
Pascal Ickrath ◽  
Agmal Scherzad ◽  
Till Jasper Meyer ◽  
Sebastian Naczenski ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Zinc Oxide Nanoparticles ◽  
Immune Modulation ◽  
Human Peripheral Blood ◽  
Human Lymphocytes ◽  
Drug Carriers ◽  
Physiological Model ◽  
Peripheral Blood Lymphocytes ◽  
Major Influence ◽  
Oxide Nanoparticles

Zinc oxide nanoparticles (ZnO-NP) are commonly used for a variety of applications in everyday life. In addition, due to its versatility, nanotechnology supports promising approaches in the medical sector. NP can act as drug-carriers in the context of targeted chemo- or immunotherapy, and might also exhibit autonomous immune-modulatory characteristics. Knowledge of potential immunosuppressive or stimulating effects of NP is indispensable for the safety of consumers as well as patients. In this study, primary human peripheral blood lymphocytes of 9 donors were treated with different sub-cytotoxic concentrations of ZnO-NP for the duration of 1, 2, or 3 days. Flow cytometry was performed to investigate changes in the activation profile and the proportion of T cell subpopulations. ZnO-NP applied in this study did not induce any significant alterations in the examined markers, indicating their lack of impairment in terms of immune modulation. However, physicochemical characteristics exert a major influence on NP-associated bioactivity. To allow a precise simulation of the complex molecular processes of immune modulation, a physiological model including the different components of an immune response is needed.

Dobutamine Antagonizes Epinephrine's Biochemical and Cardiotonic Effects 

1998 ◽  
Vol 89 (1) ◽  
pp. 49-57 ◽  
Author(s):  
Richard C. Prielipp ◽  
Drew A. MacGregor ◽  
Roger L. Royster ◽  
Neal D. Kon ◽  
Michael H. Hines ◽  
...  
Keyword(s):  
Artery Bypass ◽  
Phase 1 ◽  
Human Lymphocytes ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Camp Production ◽  
Isobolographic Analysis ◽  
Camp Generation ◽  
Vitro Model

Background Patients may receive more than one positive inotropic drug to improve myocardial function and cardiac output, with the assumption that the effects of two drugs are additive. The authors hypothesized that combinations of dobutamine and epinephrine would produce additive biochemical and hemodynamic effects. Methods The study was performed in two parts. Phase 1 used human lymphocytes in an in vitro model of cyclic adenosine monophosphate (cAMP) generation in response to dobutamine (10(-8) to 10(-4) M) or epinephrine (10(-9) M to 10(-5) M), and dobutamine and epinephrine together. Phase 2 was a clinical study in patients after aortocoronary artery bypass in which isobolographic analysis compared the cardiotonic effects of dobutamine (1.25, 2.5, or 5 microg x kg(-1) x min(-1)) or epinephrine (10, 20, or 40 ng x kg(-l) x min(-1)), alone or in combination. Results In phase 1, dobutamine increased cAMP production 41%, whereas epinephrine increased cAMP concentration approximately 200%. However, when epinephrine (10(-6) M) and dobutamine were combined, dobutamine reduced cAMP production at concentrations between 10(-6) to 10(-4) M (P = 0.001). In patients, 1.25 to 5 microg x kg(-1) x min(-1) dobutamine increased the cardiac index (CI) 15-28%. Epinephrine also increased the CI with each increase in dose. However, combining epinephrine with the two larger doses of dobutamine (2.5 and 5microg x kg(-1) x mi(-1)) did not increase the CI beyond that achieved with epinephrine and the lowest dose of dobutamine (1.25 microg x kg(-1) x min(-1)). In addition, the isobolographic analysis for equieffective concentrations of dobutamine and epinephrine suggests subadditive effects. Conclusions Dobutamine inhibits epinephrine-induced production of cAMP in human lymphocytes and appears to be subadditive by clinical and isobolographic analyses of the cardiotonic effects. These findings suggest that combinations of dobutamine and epinephrine may be less than additive.

Intracellular free magnesium in human lymphocytes and the response to lectins

1991 ◽  
Vol 80 (6) ◽  
pp. 539-547 ◽  
Author(s):  
L. L. Ng ◽  
J. E. Davies ◽  
M. C. Garrido
Keyword(s):  
Phaseolus Vulgaris ◽  
Peripheral Blood ◽  
Proliferative Response ◽  
Human Peripheral Blood ◽  
Human Lymphocytes ◽  
Peripheral Blood Lymphocytes ◽  
Blood Lymphocytes ◽  
Fluorimetric Method ◽  
Human Peripheral Blood Lymphocytes ◽  
Free Magnesium

1. Intracellular free [Mg2+] was measured in human peripheral blood lymphocytes using a fluorimetric method based on the dye furaptra. It was necessary to correct for the extracellular leakage of the dye by using either 10 mmol/l EDTA or 0.05 mmol/l Mn2+. 2. As the proliferative response of lymphocytes to mitogenic lectins has been linked to a dependence on extracellular Mg2+, the intracellular [Mg2+] was studied in lymphocytes stimulated with various mitogenic and non-mitogenic lectins. 3. Only lymphocytes treated with phytohaemagglutinin-L, a leucoagglutinin from Phaseolus vulgaris that binds to tri- and tetra-antennary complex glycoproteins, showed a marked increase in intracellular [Mg2+]. This effect was partially inhibited by N-acetylgalactosamine. The stimulation by different lectins of the incorporation of [3H]-thymidine into lymphocytes was not correlated to the changes in intracellular [Mg2+]. 4. The proliferative response of lymphocytes to lectins is therefore not wholly dependent on a rise in intracellular [Mg2+].

Activation of deoxycytidine kinase during inhibition of DNA synthesis by 2-chloro-2′-deoxyadenosine (cladribine) in human lymphocytes

1998 ◽  
Vol 56 (9) ◽  
pp. 1175-1179 ◽  
Author(s):  
Mária Sasvári-Székely ◽  
Tatjana Spasokoukotskaja ◽  
Melinda Szóke ◽  
Zsolt Csapó ◽  
Ágnes Turi ◽  
...  
Keyword(s):  
Dna Synthesis ◽  
Human Lymphocytes ◽  
Deoxycytidine Kinase ◽  
Inhibition Of Dna Synthesis
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