Echinoid phagocytes in vitro

Bertheussen, Kjell; Seljelid, Rolf

doi:10.1016/0014-4827(78)90185-4

Cited by 106 publications

(64 citation statements)

References 9 publications

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“…Cell suspensions in H & S anticoagulant exhibited normal morphology in phase contrast and differential interference contrast microscopy, and no lysis was observed. This is consistent with prevlous use of EGTA for this purpose (Bertheussen & Seljelid 1978, Messer & Wardlaw 1980, Edds et al 1983) and indicates that calcium-chelation does not produce significant morphological changes in coelomocytes, at least during exposure of up to 2 h.…”

Section: Discussionsupporting

confidence: 82%

“…The discontinuous gradient of sodium metnzoate permitted a similar separation of coelomocytes to that found by Bertheussen & Seljelid (1978). In this study, an increased steepness of the density gradient in the central band area gave a greater separation of the white sperule cells and the vibratile cells.…”

Section: Discussionsupporting

confidence: 78%

“…The clumping or clotting of coelomocytes in withdrawn coelomic fluid is known to be calcium-dependent (Kanugo 1982, Henson & Schatten 1983) and calcium-chelating agents such as EDTA (ethylenediaminetetra-acetic acid) (Kanugo 1982) and EGTA (Bertheussen & Seljelid 1978, Messer & Wardlaw 1980, Edds et al 1983) have been used to prevent cellular coagulation. In this study, EGTA (H & S anticoagulant) was found to b e satisfactory for preventing clotting and maintaining the even suspension of coelomocytes which was necessary for density-gradient separation and for Coulter counting.…”

Section: Discussionmentioning

confidence: 99%

“…For this reason, we decided to pool these 2 types of cells to ensure consistency of fractionation of fluids from different individuals. Direct con~parison of the gradient method used here with that of Bertheussen & Seljelid (1978) is limited by lack of information on the composition of the 'pure metrizoate' used in the cushion fluid by the latter authors.…”

Section: Discussionmentioning

confidence: 99%

“…A 2.0 m1 sample of coelomic fluid in H & S anticoagulant (3 : 2) was layered on top of a discontinuous gradient of sodium metnzoate (Fig. l A ) modified from Bertheussen & Seljelid (1978). Gradients were made in Beckman Ultra-Clear 14 X 89 mm centri.fuge tubes and cooled at 5°C prior to use.…”

Section: Methodsmentioning

confidence: 99%

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Experimental infection of the echinoid Strongylocentrotus droebachiensis with Paramoeba invadens: quantitative changes in the coelomic fluid

Jellett¹,

Wardlaw²,

Scheibling³

1988

Dis. Aquat. Org.

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Paramoebiasis, due to Paramoeba invadens, was transmitted from diseased to healthy echinoids Strongylocentrotus droebachiensis in the waterborne infection apparatus of Scheibl~ng & Stephenson (1984). Control echinoids were exposed to healthy S. droebachiensis in a parallel apparatus. Groups of 8 individuals from the infected treatment were sacrificed in the pre-symptomatic period and at 24 and 72 h after development of symptoms of the disease, as evidenced by loss of attachment (LOA) to aquanum surfaces. Groups of 8 individuals from the control treatment were removed and sampled at the same time. Coelom~c fluid (CF) was drawn into EGTA as an anticoagulant, and the concentration of coelomocytes determined dlrectly and after density-gradient fractionation into 3 different cell bands. The concentration of total coelomocytes was significantly lower in infected echinoids than in controls, due to smaller numbers of cells in the band containing white spherule and vibratile cells and that containing red spherule cells. The concentration of phagocytes did not differ significantly between the infected and control groups. Protein concentration in cell-free CF of infected echinoids at 72 h post-LOA (mean +SE = 446.25 k 51.69 L L g ml-l) was about twice that of control individuals (238.56 +- 16.60 pg ml-l). Terminally sick echinoids yielded CF with large numbers of bacterial contaminants. However, in vltro bactericidal activity of the fluid towards a reference marine pseudomonad did not change significantly during progression of paramoebiasis. Membrane-filtered coelomic fluid with elevated protein values from moribund, infected individuals was injected into healthy echinoids for toxin detection, but no disease symptoms appeared. Subsequent exposure of these individuals to waterborne P. invadens resulted in the usual course of dsease. While pathogenesis of pararnoebiasis remains obscure, possible mechanisms include activation of autolysis in the echinoid or production of degradative enzymes by the amoeba.

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Section: Discussionsupporting

confidence: 82%

Section: Discussionsupporting

confidence: 78%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Experimental infection of the echinoid Strongylocentrotus droebachiensis with Paramoeba invadens: quantitative changes in the coelomic fluid

Jellett¹,

Wardlaw²,

Scheibling³

1988

Dis. Aquat. Org.

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The incorporation of actin and fascin into the cytoskeleton of filopodial sea urchin coelomocytes

Otto

Bryan

1981

Cell Motility

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Echinoderm coelomocytes transform from petaloid cells with large motile lamellipodia t o filopodial forms. During this morphological transformation, actin filaments extensively reorganize from a random meshwork into tight bundles, which become the skeletons or cores of the filopodia. Antibody localization procedures show that fascin, a 58,000 dalton actin crosslinking protein, becomes incorporated into the filament bundles as they form. Isolated filopodial cores have a pronounced transverse striping pattern, which has been previously identified with fascin crosslinks, and gel electrophoresis identifies a protein in the cores that co-migrates with purified egg fascin. A few of the core fragments also have a distinctive "cap," which we presume is the membrane insertion site for actin filaments.We have developed a radioimmunoassay for fascin and have used it to study the redistribution of this protein during transformation. Data from the assay indicate that fascin constitutes about 5% of the total cell protein and that substantially more fascin, approximately 1.5-2 times more, is found in the Tritoninsoluble cytoskeletons of the filopodial cells than in the petaloid cells. Actin, measured by the DNAase I inhibition assay accounts for approximately 10% of the total cell protein. Approximately 65% of this actin is in a soluble nonfilamentous form in the petaloid cells. Our results show that actin polymerization must occur during the cell shape change, since we find approximately 25% more actin in the filopodial cytoskeleton than in the petaloid cytoskeleton. The results show a preferential incorporation of fascin into the cytoskeleton as the cells form filopodia.Key words: actin, echinoderm, fascin, filopodia, actin cross-linking protein Phagocytic coelomocytes of echinoids can change from a petaloid form to a filopodial form. The petaloid coelomocytes have large, motile lamellipodia that contain a dense meshwork or mat of actin filaments [Edds, 1977a, b] . As the cells change their shape and begin to form filopodia, the actin filaments in the lamellipodia initially aggregate into bundles at the cell periphery. These bundles then extend deeper into the cytoplasm [Edds, 1977al and eventually become the cores of filopodia, which develop as the membrane retracts around the bundles. We have been studying the mechanism of the actin filament aggregation that forms these bundles or filopodial cores.Address reprint request to J. Bryan,

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Phylogeny of natural cytotoxicity: Cytotoxic activity of coelomocytes of the purple sea urchin, Arbacia punctulata

2001

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Coelomocyte-mediated nonspecific cell cytotoxic activity against human and murine target cells by the purple sea urchin Arbacia punctulata was investigated in vitro. Cytotoxic activity toward target cells was shown to be mediated by different coelomocyte populations isolated by discontinuous density gradient centrifugation. The population of phagocytic amebocytes showed the strongest cytotoxic activity and the highest binding to human NK markers by cytometry analysis. Our immunophenotypic studies showed that A. punctulata phagocytic amebocytes are CD14(+), CD56(+), CD158b(+), CD3(-), CD4(-), CD8(-), and CD16(-). The cytotoxic activity was independent of experimental incubation temperatures, required viable effector cells, and required cell-cell contact between the effector and target cells. Sodium azide significantly decreased coelomocyte cytotoxicity, indicating that cytotoxicity is metabolically dependent, and EDTA reduction of cytotoxic activity is consistent with the involvement of divalent cations in the cytotoxic process. These data describe a population of sea urchin coelomocytes (the phagocytic amebocyte) that are CD14(+), CD56(+), and CD158b(+), with cytotoxic activities.

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Echinoid phagocytes in vitro

Cited by 106 publications

References 9 publications

Experimental infection of the echinoid Strongylocentrotus droebachiensis with Paramoeba invadens: quantitative changes in the coelomic fluid

Experimental infection of the echinoid Strongylocentrotus droebachiensis with Paramoeba invadens: quantitative changes in the coelomic fluid

The incorporation of actin and fascin into the cytoskeleton of filopodial sea urchin coelomocytes

Phylogeny of natural cytotoxicity: Cytotoxic activity of coelomocytes of the purple sea urchin, Arbacia punctulata

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