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E L Cooper

Publications and source records attributed to E L Cooper.

At least 127 records · Page 7Linked to original sources
PubMed1979

Ontogeny of cell-mediated cytotoxicity: induction of CTL in early postnatal thymocytes.

In this study we characterized the time when cytotoxic T lymphocytes (CTL) can be induced in the thymus and spleen from their immediate CTL precursors (CTL-P). In contrast to fetal or newborn thymus, the thymus of 1 to 2-day-old C57BL/6 mice contained cells that, after cultivation in vitro with allogeneic DBA/2 stimulating cells, exhibited high levels (as great or greater than that induced in adult thymocytes) of CTL activity as measured by the ability to lyse P815 (DBA/2) tumor target cells. However, CTL activity induced in spleen cells remained how during the first 5 days of life, increased sharply between 6 to 9 days, and reached adult levels at 11 to 20 days. Furthermore, early postnatal spleen cells did not suppress the adult splenic CTL response. These results suggest 1) that the full potential to generate CTL in response to an allogeneic stimulus commences in the thymus on the first day after birth and 2) a different temporal appearance of immediate CTL precursors in the thymus and spleen.

Aging↗
PubMed1979

Specificity of carbohydrate inhibition on leopard frog (Rana pipiens) erythrocyte agglutinating activity by concanavalin A and phytohemagglutinin.

1. Leopard frog (Rana pipiens) erythrocytes are agglutinated by the plant lectins concanavalin A and phytohemagglutinin. 2. Concanavalin A hemagglutination can be specifically inhibited by the sugars mannose, glucose, arabohexulose, alpha-methyl-D-mannopyranoside, N-acetyl-D-glucosamine, maltose, sucrose, trehalose and melezitose. 3. Sugars inhibiting concanavalin A hemagglutination are structurally composed of alpha-D-glucopyranosyl, alpha-D-mannopyranosyl or beta-D-fructofuranosyl residues with the same hydroxyl groups at carbons 3, 4 and 6. 4. Phytohemagglutinin hemagglutination can only be inhibited by the sugar N-acetyl-D-galactosamine. 5. Sugar inhibition of concanavalin A and phytohemagglutinin leopard frog erythrocyte agglutination is the same as that observed in many mammalian species.

Animals↗
PubMed1978

Cytochemical observations of coelomocytes from the earthworm, Lumbricus terrestris.

Coelomocytes of the earthworm, Lumbricus terrestris, were stained by cytochemical techniques to determine the biochemical composition of the seven different cell types and subtypes. The enzymes acid phosphatase and beta-glucuronidase are present in all types of coelomocytes, but are especially abundant in basophils and neutrophils; the differences in enzyme amounts correlate well with the differences in phagocytic activity of the various cell types. No peroxidase is present. The cytoplasmic basophilia of basophils is due primarily to ribonucleic acid. Basophils also contain large deposits of glycogen, with neutrophils and chloragogen cells containing somewhat lesser amounts. The predominant granules of the two types of acidophils and of granulocytes are composed of a basic protein and a neutral mucopolysaccharide or glycoprotein. A second granule population, present in low numbers in acidophils and granulocytes, but in larger numbers in basophils and neutrophils, is small in size and lipid-positive and may, in part, represent lysosomes. Lipid is especially abundant in the vesicles and granules of the two types of chloragogen cells. Some granules of chloragogen cells also contain ferrous and ferric iron and a substance with pseudoperoxidase activity. The cytoplasm contains protein, glycogen, and a neutral mucopolysaccharide. In addition, acid mucopolysaccharides are variably present in the cytoplasm of chloragogen cells, the only coelomocytes to contain this class of substances.

Acid Phosphatase↗
PubMed1977

Electron-microscopic observations of normal coelomocytes from the earthworm, Lumbricus terrestris.

Coelomocytes of the earthworm, Lumbricus terrestris, were studied by transmission electron microscopy. Four morphological cell types are distinguishable: lymphocytic coelomocytes, granulocytic coelomocytes, eleocytes (chloragogen cells), and inclusion-containing coelomocytes. Within these major categories, several distinct cell types differ and may represent developmental stages. The two types of lymphocytic coelomocytes are small with central nuclei and scanty cytoplasms. Two types of granulocytic coelomocytes differ greatly in shape and content; both have small dark-staining granules that resemble lysosomes. Electrocytes, derived from chloragogen tissue, contain a variety of granules, inclusions and vacuoles. Inclusion-containing coelomocytes appear as two types which may be immature and mature forms. Although these cells resemble those that have been referred to as erythroid cells in other invertebrates, the large inclusion bodies are apparently unrelated to hemoglobin; they can undergo morphologic transformation and be extruded by exocytosis. This information on lymphocytic, granulocytic and inclusion-containing coelomocytes is crucial to understanding more about cellular immunity in the earthworm.

Animals↗
PubMed1977

Graft rejection in earthworms: an electron microscopic study.

Graft rejection in the earthworm, Lumbricus terrestris, is mediated by granulocytic coelomocytes (neutrophils, by light microscopy). Within 1--3 days post-transplantation of body-wall xenografts, granulocytic coelomocytes migrate to the transplant site, penetrate the graft matrix, and actively phagocytize viable muscle fibers. Destruction of muscle tissues may be augmented by lymphocytic coelomocytes (basophils, by light microscopy), but these cells participate in a minor way and do so very late in the rejection process (days 11--13). Xenografts, autografts and sham-operated controls display generalized inflammatory reactions, including coelomyocyte infiltration into the grafted tissues. In autografts, however, granulocytes only penetrate the inner longitudinal muscle layers and extensive infiltration, persistence and complete destruction never occur. Lymphocytic coelomocytes are not observed in autografts or sham-operated controls. Grafts rejection by leukocytes in an advanced invertebrate confirms that aspects of cell-mediated immunity evolved early in phylogenetic history.

Animals↗
PubMed1977

The coelomocytes of the earthworm Lumbricus terrestris: morphology and phagocytic properties.

The coelomocytes of Lumbricus terrestris have been classified and described, based on Wright's stained preparations and on living cells. The five major categories consist of basophils, acidophils, neutrophils, granulocytes and chloragogen cells. Both the acidophil and chloragogen cell groups contain two subgroups. Granulocytes also exhibit heterogeneity with respect to staining properties of granules. Some possess acidophilic granules, some basophilic granules, and others contain both types. Granules of acidophils have been observed to be occasionally excreted from the cells. All cell types, with the exception of chloragogen cells, produce pseudopodia and are capable of phagocytosis, a vital component of the earthworm's immune response.

Animals↗
PubMed1977

Earthworm coelomocytes in vitro.

Contamination and low viability of earthworm coelemocytes in tissue culture have delayed in vitro studies. Using penicillin, streptomycin, tetracycline and Amphotericin B, Lumbricus terrestis coelomocytes were maintained viable and uncontaminated for 10 days at 15degreesC in medium L-15 supplemented with 5 to 10% fetal bovine serum. The coelomocytes survived for at least 10 days with 85% viability as assessed by trypan blue exclusion assays and phagocytosis of heat-killed yeast. Studies on the thymidine uptake, however, were negative. With the involvement of coelomocytes in tissue graft rejection, in vitro techniques can now be applied to study their capacity in the immune response.

Amphotericin B↗
PubMed1977

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Allergy and Immunology↗