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E L Cooper

Publications and source records attributed to E L Cooper.

175 records · Page 10Linked to original sources
PubMedDate not supplied

An enkephalin-like molecule in earthworm coelomic fluid modifies leukocyte behavior.

Substances that were immunoreactive in an RIA specific for met-enkephalin were detected following HPLC fractionation of earthworm coelomic fluid. Earthworm coelomocytes and human granulocytes were analyzed for changes in conformation based on measurements of cellular area and perimeter and expressed mathematically by using the Form Factor (FF). For coelomocytes the FF decreased following exposure to DAMA, a synthetic enkephalin analogue (D-Ala2, Met5-enkephalinamide). DAMA stimulated migration whereas untreated cells and those exposed to the specific opiate blocker naloxone did not move. The enkephalin-like molecule when exposed to human granulocytes stimulated an increased number of activated cells. Our results suggest a relationship between the immune and nervous systems of earthworms.

Animals↗
PubMedDate not supplied

Identification and structural characterization of an LYT-2/3 homolog in tunicates.

1. A serologic and structural homolog to murine Lyt-2/3 molecular complex was sought in tunicate hemocytes by using a monoclonal antibody specific to Lyt-2 framework determinants (mAb 53-6.7). 2. This antibody labeled a distinct population of tunicate hemocytes, as determined in indirect immunofluorescence and FACS analysis, and immunoprecipitated disulfide-bonded subunits from hemocytes equivalent to the 38 kDa (alpha), 34 kDa (alpha') and 30 kDa (beta) subunits of murine Lyt-2/3 molecules. 3. As in mice, tunicate alpha- and alpha' -subunits each appeared to bear three N-linked oligosaccharides, one high mannose- and two complex-type glycans and focused as a number of heterogeneous spots on IEF gels. 4. In contrast, beta-subunits of both species were associated with a single N-linked glycan of the complex type and focused as basic components of limited charge heterogeneity. 5. Based on tryptic peptide patterns, alpha and alpha' -subunits, are likely to be structurally similar in both tunicate and mouse complexes. 6. However, CNBr cleavage patterns indicated that the alpha-subunit of both species may differ in the size-location of the intrachain disulfide bridge. 7. Collectively our observations suggest the phylogenetic emergence of an Lyt-2/3 homolog at an early level of evolution.

Animals↗
PubMedDate not supplied

Results of the intercalibration study of laboratories involved in assessing the environmental consequences of the Chernobyl accident.

Within the framework of the International Chernobyl Project, the IAEA's Seibersdorf Laboratories organized an intercalibration exercise among some of the laboratories which were involved in assessing the environmental contamination in the USSR due to the accident. The objective was to assess the reliability of the radioanalytical data for food and environmental samples, which were used to assess the doses. In the initial study reference materials from the stocks of the IAEA's Analytical Quality Control Services (AQCS) were re-labelled and submitted to 71 laboratories as blind samples. These natural matrix materials included samples of milk (containing 2 different levels of radioactivity), soil, air filters and clover. The concentrations of radionuclides in these samples were known from previous intercalibration exercises. The overall range in performance was broad, which is similar to what has been observed in previous international intercomparisons. The results obtained by gamma-ray spectrometry tended to be somewhat underestimated, on average. On the other hand, the laboratories showed an overall tendency to overestimate 90Sr and possibly 239Pu, which were analysed radiochemically. The intercalibration exercise is continuing with nine materials, including: soil, grass, hay and milk powder contaminated with fallout from the Chernobyl accident. These materials, which were prepared by laboratories in the USSR, are now being tested by AQCS prior to future intercomparison exercises. Work with these materials is expected to continue for several years.

Accidents↗
PubMedDate not supplied

Characterization of a 14 kDa plant-related serine protease inhibitor and regulation of cytotoxic activity in earthworm coelomic fluid.

We have purified and characterized the serine protease inhibitor activity contained in the coelomic fluid of the earthworms, Eisenia. Serine protease inhibitor activity was stable between pH3 and 9.5, not flocculable by pH 3.0 and resistant to 100 degrees C for 15 min. or to 4 degrees C for 24 h. Ten microL of coelomic fluid was sufficient to inhibit in vitro the protease activity of 0.12 microgram of trypsin. Injection of living bacteria into earthworms resulted in increased serine protease activity 1-2 days post-injection, and increased serine protease inhibitor activity on day 4, suggesting that serine protease inhibitor is responsible for serine protease neutralization. Purified to homogeneity by affinity chromatography on trypsin, the serine protease inhibitor of Eisenia is a monomer of 14 kDa. Its partial NH2 amino acid sequence revealed a basic hydrophobic fragment which shared 68-75% homologies and 47-60% identities with several plant serine protease inhibitors. Eisenia cytotoxic activity due to the two fetidins of 40 and 45 kDa was stimulable in vitro by several serine proteases. Incubation with soybean trypsin inhibitor variant a (STIa) resulted in less cytotoxicity. The inhibitory effect occurred only when STIa was added before cell disruption. Interpretative cytotoxic scheme involving the release of intracellular cytotoxic proteins, intracellular trypsin-like activator and extracellular serine protease inhibitor suggests regulatory mechanisms for cellular/humoral immune system of earthworms.

Aeromonas hydrophila↗
PubMedDate not supplied

Isolation and characterization of earthworm hemolysins and agglutinins.

Hemolytic activity in coelomic fluid of Eisenia fetida (ECF) is due to three proteins H1, H2, H3 with molecular weights of 46, 43 and 40 kD, respectively. These proteins were isolated by preparative PAGE. H1 and H2 were shown to be stable in SDS and alpha-2-ME whereas H3 splits into two fragments with molecular weights of 18 and 21 kD after SDS treatment. IEF indicates that each protein consists of different isoforms with pIs between 5.1 and 6.2 H3 was demonstrated to be a bifunctional protein that can lyse and agglutinate erythrocytes. At 56 degrees C hemolytic activity of all three proteins was inactivated, but the agglutination activity of H3 was stable. Intracoelomic injection of erythrocytes reduced the number of hemolysins from three to two. Monospecific antisera were raised against the isolated hemolysins H1,2 and 3. The use of these antibodies and of carbohydrates as inhibitors of the biological activity of the molecules demonstrates the close structural relationship of agglutinins and hemolysins in the CF of E. fetida.

Agglutinins↗
PubMedDate not supplied

Infections, toxic chemicals and dietary peptides binding to lymphocyte receptors and tissue enzymes are major instigators of autoimmunity in autism.

Similar to many complex autoimmune diseases, genetic and environmental factors including diet, infection and xenobiotics play a critical role in the development of autism. In this study, we postulated that infectious agent antigens such as streptokinase, dietary peptides (gliadin and casein) and ethyl mercury (xenobiotic) bind to different lymphocyte receptors and tissue enzyme (DPP IV or CD26). We assessed this hypothesis first by measuring IgG, IgM and IgA antibodies against CD26, CD69, streptokinase (SK), gliadin and casein peptides and against ethyl mercury bound to human serum albumin in patients with autism. A significant percentage of children with autism developed anti-SK, anti-gliadin and casein peptides and anti-ethyl mercury antibodies, concomitant with the appearance of anti-CD26 and anti-CD69 autoantibodies. These antibodies are synthesized as a result of SK, gliadin, casein and ethyl mercury binding to CD26 and CD69, indicating that they are specific. Immune absorption demonstrated that only specific antigens, like CD26, were capable of significantly reducing serum anti-CD26 levels. However, for direct demonstration of SK, gliadin, casein and ethyl mercury to CD26 or CD69, microtiter wells were coated with CD26 or CD69 alone or in combination with SK, gliadin, casein or ethyl mercury and then reacted with enzyme labeled rabbit anti-CD26 or anti-CD69. Adding these molecules to CD26 or CD69 resulted in 28-86% inhibition of CD26 or CD69 binding to anti-CD26 or anti-CD69 antibodies. The highest % binding of these antigens or peptides to CD26 or CD69 was attributed to SK and the lowest to casein peptides. We, therefore, propose that bacterial antigens (SK), dietary peptides (gliadin, casein) and Thimerosal (ethyl mercury) in individuals with pre-disposing HLA molecules, bind to CD26 or CD69 and induce antibodies against these molecules. In conclusion, this study is apparently the first to demonstrate that dietary peptides, bacterial toxins and xenobiotics bind to lymphocyte receptors and/or tissue enzymes, resulting in autoimmune reaction in children with autism.

Adolescent↗
PubMedDate not supplied

Alternative sources of fibrinolytic, anticoagulative, antimicrobial and anticancer molecules.

The medicinal properties of earthworms in various remedies date back to 1340 A.D. and have been extended to other countries and cultures. Assays of tissue homogenates of earthworm (Eisenia foetida) have revealed a glycolipoprotein mixture referred to as G-90 that is composed of macromolecules with medical and pharmaceutical applications. There are several functions attributed to G-90: possession of several growth factors that: stimulate proliferation in cell cultures, contain an insulin like growth factor (IGF like), an immunoglobulin like growth factor (IgFG-like), possess two serine peptidases with a tyrosine code and epidermal growth factor (EGF). In contrast, G-90 exerts strong fibrinolytic and anticoagulative activity capable of lysing fibrin clots. Actions of these two properties are dependent upon concentration. Anti-coagulative activity also depends upon the kind of anticoagulants (G-90, PI, PII). G-90 can also act as antioxidant, exert antimicrobial activities in vitro and in vivo. The bacteriostatic effect is significantly greater for non-pathogenic species. Finally G-90 also participates in tissue regeneration and wound healing. Taken together, components of earthworms could be tested in certain clinical trials.

Animals↗
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In memorial.

Explore the source record for details and available documents.

District of Columbia↗
PubMedDate not supplied

Evolution of blood cells.

The most primitive blood cell may have been a protohemocyte which was first involved in phagocytosis and nutrition. When metazoans (sponges) appeared, their "blood" cells, the archeocytes, were phagocytic. In diploblastic cnidarians (e.g. Hydra) blood cells occur in the primitive mesenchyme or mesoglea and are still phagocytic. Although the flatworms and nemertean worms possess a pseudocoelom, a progressive differentiation of several leukocytic types occurred. In coelomate annelids or segmented worms, differentiated cells appeared that distributed food and oxygen, thus erythrocytes evolved in certain marine or polychaete annelids. The Annelida also show differentiation of leukocytes that resemble granulocytes, lymphocytes and monocytes, and cell-mediated immunity that persists throughout later evolution. The Mollusca, Arthropoda, Echinodermata and Tunicata possess essentially the same features as the annelids. The vertebrate blood cells may have evolved from the tunicates via the echinoderm line, the deuterostome invertebrates, although analogous blood cells are present in the annelids, molluscs, and arthropods, the protostomes. The vertebrate plan of blood cell differentiation occurs in two compartments: bone marrow (for both lymphoid and myeloid cells) and lymphoid organs (e.g. thymus, lymph nodes) for lymphocytes.

Animals↗
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Preliminary evidence of modulating Th1 cytokine after allergen challenge.

We wanted to determine whether a paradigm switch in Th1/Th2 phenotypes in splenic lymphocytes could be induced in BALB/c mice after ultraviolet-B (UVB) irradiation and exposure to pollen. Results showed that UVB irradiation increased IL-1 but decreased IL-12 in vivo, and caused significant cell destruction of macrophages in vitro. We then gave mice cedar pollen intranasally, UVB irradiation (6kJ/cm2), and then splenic lymphocyte functions were examined. Results revealed that: 1) the level of IFN-gamma of splenic lymphocytes from UVB-irradiated mice was significantly decreased, especially in pollen-exposed mice; 2) UVB irradiation did not augment IL-4 levels; 3) IgE levels from UVB-irradiated mice did not increase. UVB irradiation (6kJ/cm2) did not induce Th2 response but suppressed Th1 cytokine, suggesting that Th1 could be more susceptible to UVB irradiation than Th2.

Journal Article↗
PubMedDate not supplied

Allogeneic killing by earthworm effector cells.

We observed spontaneous allogeneic cytotoxicity by coelomocytes (Lumbricus terrestris) using three assays: trypan blue, lactate dehydrogenase release and chromium-51 release. Cell-cell contact may not be essential to effect cytotoxicity, since killing of allogeneic cells occurred in pooled allogeneic coelomic fluid derived from worms raised in two different geographic locales. We observed no significant spontaneous cytotoxicity against autogeneic target coelomocytes haptenated with 2,4,6-trinitrobenzene sulfonic acid; however, coelomocytes effected significant spontaneous cytotoxicity against haptenated allogeneic targets. These results support the view that earthworm coelomocytes can act as effector cells that can specifically kill nonself target cells.

Animals↗
PubMedDate not supplied

Immunity and neoplasia in Mollusks.

The Mollusca is one of the largest of invertebrate phyla. Two major classes, the Gastropoda and the Pelecypoda, have been the subject of numerous studies on immunity and neoplasia. Investigations of immunity have dealt with cellular and humoral aspects, phagocytosis and encapsulation, and rejection of foreign tissue grafts. Work on humoral responses has focused on lysozyme, the hemagglutinins (especially in the oyster), and the clearance of certain antigens. Neoplasms in these animals resemble certain cancers in vertebrates, but it is not clear whether a relationship exists between the invertebrate immune system and the development of neoplasia. Studies of immunity and neoplasia in invertebrates may reveal how these two phenomena of living systems have evolved.

Animals↗