scholarly journals Exposure of cultured murine peritoneal macrophages to low concentrations of beryllium induces increases in intracellular calcium concentrations and stimulates DNA synthesis

1999 ◽  
Vol 65 (6) ◽  
pp. 786-791 ◽  
Author(s):  
Uma K. Misra ◽  
G. Gawdi ◽  
Salvatore V. Pizzo ◽  
James G. Lewis
Keyword(s):  
Dna Synthesis ◽  
Intracellular Calcium ◽  
Peritoneal Macrophages ◽  
Low Concentrations ◽  
Murine Peritoneal Macrophages

Increased Aggregation and Secretion Responses of Human Platelets when Loaded with the Calcium Fluorescent Probes Quin2 and Fura-2

1987 ◽  
Vol 58 (02) ◽  
pp. 737-743 ◽  
Author(s):  
Frarnçois Lanza ◽  
Alain Beretz ◽  
Martial Kubina ◽  
Jean-Pierre Cazenave
Keyword(s):  
Intracellular Calcium ◽  
Shape Change ◽  
Calcium Ionophore ◽  
Human Platelets ◽  
Arachidonic Acid Metabolism ◽  
Free Calcium ◽  
Membrane Bilayer ◽  
Fluorescent Indicators ◽  
Fura 2 ◽  
Low Concentrations

SummaryIncorporation into human platelets of the calcium fluorescent indicators quin2 or fura-2 at low concentrations used to measure intracellular free calcium leads to the potentiation of the effects of agonists on platelets. This was shown by increased aggregatory and secretory responses of quin2 or fura-2 loaded platelets after stimulation with ADP, PAP and with low concentrations of thrombin, collagen, the endoperoxide analog U-46619 and the calcium ionophore A 23187. Quin2 and fura-2 mediated platelet sensitisation could be due to altered arachidonic acid metabolism since it was inhibited by prior treatment with the cydooxygenase inhibitor acetylsalicylate. In contrast, platelets loaded with higher concentrations of calcium chelators exhibited diminished aggregation responses to all aggregating agents. This latter effect was accompanied by increased fluidity of the platelet plasma membrane bilayer and by the exposure of a new pool of membranes to the outer surface of platelets, as monitored with trimethylammonium- diphenylhexatriene (TMA-DPH) in platelets loaded with the non-fluorescent calcium probe analog MAPT. In contrast, low concentrations of quin2 did not potentiate shape change of platelets activated with ADP. Thus, shape change and aggregation can be influenced separately by intracellular Ca2+ chelators. We conclude that platelet responses are altered by the incorporation of intracellular calcium chelators at concentrations used to monitor intracellular calcium changes.

Swainsonine Modulation of Protein Kinase C Activity in Murine Peritoneal Macrophages

1990 ◽  
Vol 2 (10) ◽  
pp. 333-338 ◽  
Author(s):  
Pascal Breton ◽  
Amha Asseffa ◽  
Krzysztof Grzegorzewski ◽  
Steven K. Akiyama ◽  
Sandra L. White ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Peritoneal Macrophages ◽  
Kinase C ◽  
Protein Kinase C Activity ◽  
Murine Peritoneal Macrophages

scholarly journals Differential Bacterial Survival, Replication, and Apoptosis-Inducing Ability of Salmonella Serovars within Human and Murine Macrophages

2000 ◽  
Vol 68 (3) ◽  
pp. 1005-1013 ◽  
Author(s):  
William R. Schwan ◽  
Xiao-Zhe Huang ◽  
Lan Hu ◽  
Dennis J. Kopecko
Keyword(s):  
Typhoid Fever ◽  
Systemic Infection ◽  
Peritoneal Macrophages ◽  
Human Macrophage ◽  
U937 Cells ◽  
Bacterial Survival ◽  
Human Macrophages ◽  
Macrophage Cells ◽  
Serovar Typhimurium ◽  
Murine Peritoneal Macrophages

ABSTRACT Salmonella serovars are associated with human diseases that range from mild gastroenteritis to host-disseminated enteric fever. Human infections by Salmonella enterica serovar Typhi can lead to typhoid fever, but this serovar does not typically cause disease in mice or other animals. In contrast, S. enterica serovar Typhimurium and S. entericaserovar Enteritidis, which are usually linked to localized gastroenteritis in humans and some animal species, elicit a systemic infection in mice. To better understand these observations, multiple strains of each of several chosen serovars of Salmonellawere tested for the ability in the nonopsonized state to enter, survive, and replicate within human macrophage cells (U937 and elutriated primary cells) compared with murine macrophage cells (J774A.1 and primary peritoneal cells); in addition, death of the infected macrophages was monitored. The serovar Typhimurium strains all demonstrated enhanced survival within J774A.1 cells and murine peritoneal macrophages, compared with the significant, almost 100-fold declines in viable counts noted for serovar Typhi strains. Viable counts for serovar Enteritidis either matched the level of serovar Typhi (J774A.1 macrophages) or were comparable to counts for serovar Typhimurium (murine peritoneal macrophages). Apoptosis was significantly higher in J774A.1 cells infected with serovar Typhimurium strain LT2 compared to serovar Typhi strain Ty2. On the other hand, serovar Typhi survived at a level up to 100-fold higher in elutriated human macrophages and 2- to 3-fold higher in U937 cells compared to the serovar Typhimurium and Enteritidis strains tested. Despite the differential multiplication of serovar Typhi during infection of U937 cells, serovar Typhi caused significantly less apoptosis than infections with serovar Typhimurium. These observations indicate variability in intramacrophage survival and host cytotoxicity among the various serovars and are the first to show differences in the apoptotic response of distinctSalmonella serovars residing in human macrophage cells. These studies suggest that nonopsonized serovar Typhimurium enters, multiplies within, and causes considerable, acute death of macrophages, leading to a highly virulent infection in mice (resulting in death within 14 days). In striking contrast, nonopsonized serovar Typhi survives silently and chronically within human macrophages, causing little cell death, which allows for intrahost dissemination and typhoid fever (low host mortality). The type of disease associated with any particular serovar of Salmonellais linked to the ability of that serovar both to persist within and to elicit damage in a specific host's macrophage cells.

Activation of murine peritoneal macrophages by Salmonella typhimurium

1989 ◽  
Vol 26 (1-2) ◽  
pp. 208-210
Author(s):  
J. A. M. Langermans ◽  
P. H. Nibbering ◽  
R. Furth
Keyword(s):  
Salmonella Typhimurium ◽  
Peritoneal Macrophages ◽  
Murine Peritoneal Macrophages

scholarly journals Infection with Mycobacterium aviumDifferentially Regulates the Expression of Iron Transport Protein mRNA in Murine Peritoneal Macrophages

2001 ◽  
Vol 69 (11) ◽  
pp. 6618-6624 ◽  
Author(s):  
Wangjian Zhong ◽  
William P. Lafuse ◽  
Bruce S. Zwilling
Keyword(s):  
Host Defense ◽  
Transferrin Receptor ◽  
Iron Transport ◽  
Peritoneal Macrophages ◽  
Natural Resistance ◽  
Intracellular Pathogens ◽  
Mrna Levels ◽  
Iron Availability ◽  
Iron Transporter ◽  
Murine Peritoneal Macrophages

ABSTRACT Iron is an important element for the growth of microorganisms as well as in the defense of the host by serving as a catalyst for the generation of free radicals via the Fenton/Haber-Weiss reactions. The iron transporter natural resistance-associated macrophage protein 1 (Nramp1) confers resistance to the growth of a variety of intracellular pathogens including Mycobacterium avium. Recently several other proteins that are involved in iron transport, including the highly homologous iron transporter Nramp2 and the transferrin receptor-associated protein HFE (hereditary hemochromatosis protein), have been described. The relationship of these proteins to host defense and to the growth of intracellular pathogens is not known. Here, we report that infection with M. avium differentially regulates mRNA expression of the proteins associated with iron transport in murine peritoneal macrophages. Both Nramp1 and Nramp2 mRNA levels increase following infection, while the expression of transferrin receptor mRNA decreases. The level of expression of HFE mRNA remains unchanged. The difference in the expression of the mRNA of these proteins following infection or cytokine stimulation suggests that they may play an important role in host defense by maintaining a delicate balance between iron availability for host defense and at the same time limiting iron availability for microbial growth.

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