Characterization of platelet‐activating factor‐induced elevation of cytosolic free calcium concentration in eosinophils

Kroegel, Claus; Pleass, Robert; Yukawa, Tatsuo; Chung, Kian Fan; Westwick, John; Barnes, Peter J.

doi:10.1016/0014-5793(89)81214-1

Cited by 45 publications

(16 citation statements)

References 19 publications

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“…Although the conclusive relationship between the intracellular Ca 2+ mobilization and leukotriene synthesis remains to be established, Ca 2+ enhances 5-lipoxygenase activity [32,33]. The addition of PAF to human eosino-phils leads to their degranulation [34] and transiently in-creases the intracellular concentration of free Ca 2+ [35,36]. The exogenous PAF C-18 was observed to mobilize the intracellular Ca 2+ in the macrophages from asthmatic patients to a significantly greater extent than those from nonasthmatic subjects.…”

Section: Discussionmentioning

confidence: 99%

Platelet-activating factor increases leukotriene B4 release in stimulated alveolar macrophages from asthmatic patients

Shindo¹,

Koide²,

Fukumura³

1998

Eur Respir J

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This study was designed to examine further the role of platelet-activating factor (PAF) in asthma, comparing leukotriene B4 (LTB4) release, 5-lipoxygenase activity and intracellular calcium levels ([Ca2+]i) in macrophages. LTB4 and other lipoxygenase metabolites in macrophages in bronchoalveolar lavage fluids obtained from 23 asthmatic patients and 20 control subjects were measured by reverse-phase high-performance liquid chromatography. [Ca2+]i was monitored using the fluorescent probe fura-2. The basal LTB4 release of resting macrophages was not different between groups (0.02+/-0.01 versus 0.05+/-0.02 ng x 10(-6) cells). When stimulated with calcium ionophore A23187 (2.5 microM), however, macrophages from asthmatic patients released more LTB4 than cells from control subjects (30.2+/-3.4 versus 13.7+/-2.1 ng x 10(-6) cells). Although PAF alone did not alter LTB4 release, it enhanced the response to subsequent A23187 stimulation. This effect was noted following short treatment (i.e., 5 min) at concentrations of > or =1.0 microM PAF, with the maximal effect noted after treatment with 5.0 microM PAF + 2.5 microM A23187 (105.1+/-6.7 versus 15.3+/-2.6 ng x 10(-6) cells). Treatment of macrophages with PAF also increased 5-lipoxygenase activity and [Ca2+]i more in cytosols from asthmatic patients than in cytosols from control subjects. These findings support a role of intracellular calcium in the activation of 5-lipoxygenase which, in turn, augments the release of leukotriene B4. Because levels of platelet-activating factor may be increased in the lung during asthma and can increase the subsequent release of a chemotactic mediator leukotriene B4, from macrophages, these findings suggest that platelet-activating factor may prime the constitutive cells of the lung to augment inflammatory effects important in the pathogenesis of asthma.

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Section: Discussionmentioning

confidence: 99%

Platelet-activating factor increases leukotriene B4 release in stimulated alveolar macrophages from asthmatic patients

Shindo¹,

Koide²,

Fukumura³

1998

Eur Respir J

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“…Since an array of mediators are released during asthmatic inflammation [153,164,166], which may be responsible for both chemotactic attraction to the inflammatory focus and stimulation of cellular effector functions, the attenuated functional capacity of BAL eosinophils may be due to a cellular desensitization process, as has been previously described for eosinophils [72,73,167]. Interestingly, neutrophils recruited to the lung following segmental antigen provocation have also been found to be desensitized to LTB 4 [168], suggesting that desensitization during tissue infiltration may be a necessary general process for accumulation at the spot with the highest level of chemoattractant.…”

Section: Functional Heterogeneitymentioning

confidence: 97%

“…At the same time, upon arrival at the inflammatory site, i.e. in the airway mucosa, the eosinophil may become immobilized and hyporeactive as a result of cell desensitization due to chemotactic factors, such as PAF [163][164][165][166][167][168]318] …”

Section: General Mechanismsmentioning

confidence: 99%

Pulmonary immune cells in health and disease: the eosinophil leucocyte (Part I)

Kroegel¹,

Virchow²,

Luttmann³

et al. 1994

Eur Respir J

128

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P Pu ul lm mo on na ar ry y i im mm mu un ne e c ce el ll ls s i in n h he ea al lt th h a an nd d d di is se ea as se e: : t th he e e eo os si in no op ph hi il l l le eu uc co oc cy yt te e ( (P Pa ar rt t I I) ) ABSTRACT: Increasing evidence has accumulated to suggest that eosinophils play a key role in the pathogenesis of asthma and other pulmonary diseases by damaging infiltrated bronchial tissue and lung parenchyma. The first part of this review on eosinophils describes the cellular characteristics and properties of the cell, which help in understanding its role in disease. The article focuses on origin, maturation and differentiation of the eosinophil, its morphological and phenotypical properties, as well as its preformed and newly generated mediators of inflammation. The cause and putative significance of eosinophil heterogeneity in respect to function and density will also be discussed. In addition, the naturally occurring mediators through which eosinophils are activated and communicate with other inflammatory cells are outlined.The first part closes with new aspects of eosinophil recruitment from the circulation into perivascular tissue, including nonselective and putative selective adhesion mechanisms and chemotaxis.

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“…[Ca 2+ ] i was monitored with a CAF110 spectrofluorimeter (λ ex = 340 and 380 nm, λ em = 510 nm; JASCO, Tokyo). Calibration has been described previously [19]. …”

Section: Methodsmentioning

confidence: 99%

Effect of Interleukin–3, Interleukin 5 and Hyaluronic Acid on Cultured Eosinophils Derived from Human Umbilical Cord Blood Mononuclear Cells

Ôhashi

Takei

Ide

et al. 1999

Int Arch Allergy Immunol

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Background: Several studies have shown that cultured eosinophils can be generated from human umbilical cord blood mononuclear cells (UCMC) in the presence of interleukin (IL)–3 and IL–5 in vitro. Other reports have indicated that cellular adhesion to hyaluronic acid (HA) enhances the proliferation of cultured eosinophils derived from CD34+ cells purified from UCMC. The aim of this study was to obtain large numbers of mature eosinophils from UCMC using IL–3, IL–5 and HA, and to investigate their functions. Methods: We examined several combinations of IL–3 and IL–5 and their effect on eosinophil development from UCMC in HA–coated on non–coated flasks. We also examined whether cultured eosinophils degranulated eosinophil–derived neurotoxin (EDN) induced by secretory immunoglobulin A conjugated to sepharose beads (sIgA–beads) and responded to eotaxin. Results: Culture with HA–coated flasks for 35 days (in the presence of IL–3 and IL–5, with IL–3 omitted after day 14 of culture) caused a 11.2–fold augmentation in the proliferation of UCMC. On day 35 of the culture, 98% of cultured cells were eosinophils judging from May–Grünwald and Giemsa staining and transmission electron micrographs. The EDN content of the cultured eosinophils on day 35 was 156 ng/105 cells. Cultured eosinophils degranulated EDN induced by sIgA–beads and responded to eotaxin by chemotaxis and intracellular Ca2+ mobilization. Conclusion: We found a useful culture system to obtain large numbers of eosinophils derived from UCMC, which may facilitate the investigation of eosinophil function, since there was no significant difference in response to sIgA–beads and eotaxin between cultured and peripheral eosinophils.

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Characterization of platelet‐activating factor‐induced elevation of cytosolic free calcium concentration in eosinophils

Cited by 45 publications

References 19 publications

Platelet-activating factor increases leukotriene B4 release in stimulated alveolar macrophages from asthmatic patients

Platelet-activating factor increases leukotriene B4 release in stimulated alveolar macrophages from asthmatic patients

Pulmonary immune cells in health and disease: the eosinophil leucocyte (Part I)

Effect of Interleukin–3, Interleukin 5 and Hyaluronic Acid on Cultured Eosinophils Derived from Human Umbilical Cord Blood Mononuclear Cells

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