Erythrocyte membrane structural features that are critical for the lytic reaction of Spirograhis spallanzani coelomic fluid hemolysin.

1. Hemolytic activity of Spirographis spallanzani coelomic fluid depends on factor(s) strongly influenced by calcium but not by sulfhydril or disulfide reagents. 2.

Isolation of cytolytic granules from sea urchin amoebocytes.

Calcium-dependent, heat-labile lytic activity was detected in whole Paracentrotus lividus coelomocytes. The molecules responsible for this activity were mainly expressed by an enriched amoebocyte population and were contained in cytoplasmic granules which could be isolated by Percoll density gradient centrifugation. The isolated cytoplasmic granules were small (0.

Sea urchin coelomic fluid agglutinin mediates coelomocyte adhesion.

The sea urchin Paracentrotus lividus coelomic fluid was found to contain agglutinin which agglutinates animal erythrocytes and promotes adhesion of autologous coelomocytes. Hemagglutinating activity depended upon the presence of calcium ions and was relatively heat-stable. Through a combination of methods including ammonium sulfate precipitation and both size exclusion and ion exchange chromatographies, we purified the anti-rabbit agglutinating factor.

A 220 kDa coelomocyte aggregating factor involved in Holothuria polii cellular clotting.

Agglutinating molecules are released by Holothuria polii coelomocytes. In our in vitro system we observe that release depends on the number of coelomocytes but it seems not to be time- and temperature-dependent. The factor responsible for agglutination was isolated from an Edds isotonic solution coelomocyte suspension medium and purified by ammonium sulfate precipitation, gel filtration and ion exchange chromatography; it had a molecular mass of about 220 kDa on an sodium dodecyl sulfate polyacrylamide gel.

Binding properties of Paracentrotus lividus (Echinoidea) hemolysin.

1. Paracentrotus lividus hemolysin binds erythrocytes, zymosan particles, lipopolysaccharide and laminarin surfaces but not auto and allogeneic cell membranes. 2.

Hemolysins: pore-forming proteins in invertebrates.

Invertebrates possess lytic molecules which lyse vertebrate erythrocytes. In all the species studied so far, hemolytic activity depends on proteins which possess a wide range of reactivity. It is generally calcium-dependent and heat-labile, although calcium-independent and heat-stable hemolysins have also been detected.

B-lymphocyte populations in Xenopus laevis.

Two-color immunofluorescence technique was used to show the development and distribution of surface mu- cytoplasmic mu+ (s mu- c mu+) pre-B, s mu+ B- and s mu+ cIg+ plasma cells in metamorphic, postmetamorphic, and adult Xenopus. Generation of pre-B cells was evident in hematopoietic liver and spleen, but not in bone marrow, thymus, and duodenal mucosa. Surface immunoglobulin positive small lymphocytes were the most abundant in the spleen while plasma cells were detected in the thymus, duodenal mucosa, spleen, and liver.

The coelomocytes of Holothuria polii (Echinodermata). II. Cytochemical staining properties.

Histochemical studies by traditional staining methods for lipids, mucopolysaccharides and proteins and histoenzymatic reactions typical of lysosomal activity were carried out on the principal coelomocyte types of Holothuria polii. These are considered to be the cellular contigent of the immune response, and in Holothuria polii, they probably take part also in clotting events.

Engagement of Polian vesicles during Holothuria polii response to erythrocyte injection.

The Holothuria polii Polian vesicles are organs of inflammatory responsiveness. Under antigenic provocation, they respond with remarkable structural modifications. They are also able to produce brown bodies that represent a survival strategy, used by the holothuroid, to rid the body of non-self material presented to it.

Interactions between earthworm hemolysins and sheep red blood cell membranes.

The hemolytic activity exhibited by the coelomic fluid of the Annelid Eisenia fetida andrei is mediated by two lipoproteins of mass 40 and 45 kDa, each of them capable of hemolysis. Such an activity is not inhibited by zymosan, inulin or lipopolysaccharide (LPS), nor by hydrazine or methylamine, suggesting that earthworm hemolysins are not related to C3 or C3b complement components. Among the membrane lipids tested (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingomyelin and cholesterol) only sphingomyelin inhibited hemolysis.

Arylsulphatase in echinoderm immunocompetent cells.

Two peaks of arylsulphatase activity were detected biochemically in coelomocyte lysate preparations of seven different Echinodermata species. Both peaks were inactivated by sulphite and sulphate ions, indicating that Type II arylsulphatase is present in the coelomocytes of the species tested. Arylsulphatase was localized histochemically in the granules of spherula cells, suggesting that in echinoderms a common cell type with granulocyte-like functions is present.

Arylsulfatase in coelomocytes of Holothuria polii.

Holothuria polii coelomocytes possess arylsulfatase enzymes. Two pH optima were found for arylsulfatase activity in cell lysate preparations, one at pH 5.0 and the other at pH 5.

Studies on Holothuria polii (Echinodermata) coelomocyte lysate. II. Isolation of coelomocyte hemolysins.

The lytic activity of the Holothuria polii coelomocyte lysate resides in two electrophoretically distinct hemolysins identified as He1 and He2. He1 represents the calcium dependent, heat-labile component whereas He2 is calcium independent and heat-stable. The two hemolysins share serological identity.

The hemolysin-producer coelomocytes in Holothuria polii.

Using sodium metrizoate discontinuous gradients, two hemolysin-producer amebocyte populations have been separated from total circulating Holothuria polii coelomocytes. The amebocytes of population 1 are responsible for the production of the calcium-dependent and temperature-labile hemolysin, whereas those of population 2 produce the calcium-independent and temperature-stable one. The intracytoplasmic hemolysins were evidenced also by immunofluorescence.

Membrane damage by coelomic fluid from Holothuria polii (Echinodermata).

Rabbit erythrocyte membranes lyzed by Holothuria polii coelomic fluid, observed under the electron microscope, present lesions consisting of irregular holes which are heterogeneous in size (ranging from 50 A to 250 A) and ultrastructurally different from the ring-like structure produced by human complement. The protein pattern associated with the lyzed membrane was also examined.

The membrane attack complex of Xenopus laevis complement.

Rabbit erythrocyte membranes lyzed by Xenopus laevis serum exhibited a typical ultrastructural complement lesion with an inner diameter of 80 +/- 9 A. The protein pattern associated with lyzed membrane is compared to a similar human preparation.

Inhibitory activity of sphingomyelin on hemolytic activity of coelomic fluid of Holothuria polii (Echinodermata).

The hemolytic activity of coelomic fluid from Holothuria polii is specifically inhibited by sphingomyelin. This phospholipid is the constituent of the membrane which probably interacts with the hemolysin thereby leading to the lysis.

Studies on Holothuria polii (Echinodermata) coelomocyte lysate. I. Hemolytic activity of coelomocyte hemolysins.

The Holothuria polii coelomocyte lysate contains two trypsin-resistant lytic proteins having different chemico-physical properties: a calcium dependent and heat-labile hemolysin that is probably a constitutive component of the coelomic fluid, and another calcium independent and heat-stable one that is released after immunological stimulation; it is therefore not detectable in natural conditions. The sphingomyelin seems to be the membrane receptor with which both hemolysins interact producing lysis.

Chromatographic separation of coelomic fluid from Holothuria polii (echinodermata) and partial characterization of the fractions reacting with erythrocytes.

Coelomic fluid preparations from Holothuria polii were passed through a Bio-gel A5m column. The 3 separated protein peaks possess hemagglutinating or hemolytic activity against rabbit erythrocytes. Electrophoretic and immunochemical methods showed that 2 identical protein subunits characterized hemagglutinins of different size.

Carbohydrate binding specificity and purification by biospecific affinity chromatography of Ascidia malaca Traust. hemagglutinins.

The carbohydrate specificities of Ascidia malaca serum hemagglutinins were determined by hemagglutination inhibition tests. Analysis of agglutinins against rabbit and human A, B, O erythrocytes suggests that the size of the combining site corresponds to a disaccharide with a specificity for saccharides containing a D-galacto configuration (D-melibiose, D-raffinose, D-galactose, alpha-lactose, lactulose, L-arabinose). No anomeric specificity was observed with oligosaccharides.