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An eosinophil chemotactic (ECF) was partially purified from plerocercoids of Spirometra erinacei by a combination of anion-exchange chromatography on DE52 and gel filtration on Sephacryl S-200. The molecular weight of ECF was estimated to be 25,000-45,000 by high-pressure liquid chromatography. The ECF was bound with concanavalin A-Sepharose. The ECF was sensitive to periodate oxidation and to heating (56 degrees C, 30 min). On isoelectric focusing, eosinophil chemotactic activity was clearly revealed at pI 4.1. These results suggest that ECF of S. erinacei plerocercoid is an acidic glycoprotein. An intradermal injection of ECF eosinophil attractions in the normal guinea pig skin.

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In vitro actions of purified plerocercoid growth factor (PGF) were compared with those of insulin and human growth hormone (hGH) in adipose tissue from normal male rats. Insulin-like effects were measured by the ability of PGF, insulin, or hGH to stimulate oxidation of [U-14C]glucose to 14CO2, to stimulate lipogenesis, and to inhibit epinephrine-induced lipolysis. PGF and insulin stimulated significant increases in glucose oxidation and lipogenesis in adipose tissue that had not been preincubated as well as in tissue that had been preincubated. hGH stimulated insulin-like effects only in tissue that had been preincubated for 3 hr. Insulin, hGH, and PGF inhibited epinephrine-induced lipolysis of preincubated (3 hr) adipose tissue. hGH produced a dramatic lipolytic response in tissue freshly removed from normal rats but no dose of PGF was lipolytic. PGF did not displace 125I-insulin from its receptors on adipocytes but did competitively inhibit 125I-hGH binding to adipocytes. These results suggest that PGF has direct insulin-like actions which are initiated by binding a GH receptor, but PGF had no anti-insulin action and the insulin-like activity of PGF was unaffected by refractoriness of adipose tissue to GH.

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The distribution of labeled cyanocobalamin (CN-[57Co]Cbl = [57Co]-vitamin B12) in pleurocercoids and adult tapeworms of Spirometra mansonoides was studied during development in mice 22 days days PI, respectively. Plerocercoid scolices, obtained by cutting away their bodies or by in vitro enzymatic dissolution of the bodies, were pulsed with CN- magnitude of 57Co Cbl for 1h at 37 degrees C and reimplanted subcutaneously into mice or given per os to cats. In regenerated plerocercoids, the highest concentration of magnitude of 57Co Cbl occurred in the scolex and then decreased posteriorly in the newly-formed tissues of the body. Approximately 60% of the total magnitude of 57Co Cbl present remained concentrated in the scolex following body regeneration plerocercoids and adult tapeworms of Spirometra mansonoides was studied during development in mice 22 days post-infection (PI) and in cats 16 days PI, respectively. Plerocercoid scolices, obtained by cutting away their bodies or by in vitro enzymatic dissolution of the bodies, were pulsed with CN-[57Co]Cbl for 1 h at 37 degrees C and reimplanted subcutaneously into mice or given per os to cats. In regenerated plerocercoids, the highest concentration of [57Co]Cbl occurred in the scolex and then decreased posteriorly in the newly-formed tissues of the body. Approximately 60% of the total [57Co]Cbl present remained concentrated in the scolex following body regeneration for up to 109 days PI. This high [57Co]Cbl concentration in the plerocercoid scolex was bound to protein and appears to be maintained by a complex homeostatic mechanism in association with directional transport of [57Co]Cbl to the scolex with ultimate depletion along the length of the body.(ABSTRACT TRUNCATED AT 250 WORDS)

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The plerocercoid stage of the tapeworm Spirometra mansonoides produces a functional analog of human growth hormone (hGH). Among the similarities between plerocercoid growth factor (PGF) and hGH is competition for the same receptors on rabbit liver membranes. To take advantage of this characteristic in a purification scheme for PGF, rabbit liver microsomes were solubilized in Triton X-100 and the hGH receptors were purified over an hGH affinity column. The purified receptors from six rabbit livers were coupled to Affi-Gel-10 to create a receptor affinity column which was used to purify PGF. Chromatography of crude PGF over the receptor column resulted in a 1044 fold increase in specific activity. SDS-PAGE in the presence of 2-mercaptoethanol showed that the affinity-purified PGF contained three protein bands with apparent Mrs of 27.5 K, 22 K, and 16.7 K. Injections of the partially-purified PGF into hypophysectomized rats produced a dose-dependent growth response and 400 ng eq of PGF each day for 10 days stimulated a growth response not significantly different from that produced by 250 micrograms of bovine GH each day. Receptor affinity chromatography was an effective method to purify small amounts of PGF in a single step with negligible loss of biological activity.

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The brush border-like surface of the tegument of the adult and the plerocercoid larva of a pseudophyllidean cestode, Spirometra mansonoides, has been shown to contain hydroxylated galactosylceramides. D-Galactosyl-N-(2-D-hydroxyoctadecanoyl)-D-phytosphingosine, D-galactosyl-N-(2-D-hydroxyoctadecanoyl)-D-dihydrosphingosine and D-galactosyl-N-(octadecanoyl)-D-phytosphingosine were identified as major glycosphingolipids in a tegumental plasma membrane fraction with associated microtriches, by combinations of chromatography (column, high performance thin-layer, gas-liquid), mass spectrometry (electron impact, field desorption, fast atom bombardment, collisionally induced decomposition) and proton nuclear magnetic resonance spectrometry. Galactosylceramides with hydroxylated long chain bases and fatty acids are known to occur in some eukaryotic microbes and in cells of vertebrate tissues exposed to plasma membrane destabilizing environments. This has led to a proposal that the capacity of hydroxylated ceramide moieties for intermolecular hydrogen bonding among themselves and with phosphoglycerides acts to stabilize the plasma membrane. Saturated fatty acyl groups in the ceramides would enhance stabilization by their orderly packing in the lipid bilayer. Consequently, the presence of such hydroxylated galactosylceramides in the tegument surface of S. mansonoides may contribute to the maintenance of its normal barrier properties in the face of the varied environmental insults encountered by the cestode in its life-cycle.

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A factor produced by the plerocercoid stage of S. mansonoides mimics some, but not all, of the actions reported for hGH. The biological actions of plerocercoid growth factor (PGF) suggest structural similarity to human GH (hGH). Plerocercoid membranes were solubilized, and PGF was purified more than 1000-fold by hGH receptor affinity chromatography. The ability of purified PGF to displace [125I]hGH from monoclonal antibodies specific for four distinct nonoverlapping antigenic determinants of hGH and from an anti-hGH polyclonal antibody was tested in liquid phase RIA. All of the hGH antibodies cross-reacted with PGF, with potencies ranging from more than 60% to less than 1% that of the hGH standard. Of the four major epitopes of hGH defined by the monoclonal antibodies used in this study, only one is not represented to a significant extent in PGF. The epitope of hGH that is only marginally present in PGF is highly conformationally dependent, and a minor difference in the structure of PGF (compared to hGH) could result in a significant conformational change. The dramatic cross-reactivity between anti-hGH antibodies and PGF suggests that the similarities in biological activities between these two substances are based in significant molecular homology.

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European Spirometra forms corresponding to S. erinaceieuropaei in morphology, host specificity and periodical destrobilation were tested for a Sparganum Growth Factor (SGF "mansonoides") acting upon hypophysectomized male rats. A Polish form as well as Thai and Burmese forms did not show a SGF "mansonoides". The Polish form partially caused increased growth in normal laboratory mice (similar to a form from Thailand) and in Cricetulus griseus (SGF "non-mansonoides", restricted by host resistance). Procyon lotor can act both as paratenic and as definitive host for the Polish form. The Polish, Thai and Burmese forms are attributed to S. erinaceieuropaei. A Bulgarian form showed a typical SGF "mansonoides". 4 hyposectomized 100 g rats, each of which were implanted 5 spargana subcutaneously, showed weight gains up to 400 g within 7 to 8 weeks. Therefore, this Bulgarian form is treated provisionally as Spirometra sp.

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Carbohydrate distribution within vesicles of the tegumental cytoplasm of the procercoid of Spirometra mansonoides indicated that there are at least three morphologically and histochemically different vesicular types, but only one vesicular type was present in the subtegumental perikarya. This distribution of vesicles and the presence of morphologically intermediate forms could represent either the discontinuous, sequential synthesis of the various vesicular types or continued differentiation of vesicles observed in the synthetic regions of the perikarya once they move to the tegumental cytoplasm.

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The kinds and amounts of the lipids of each stage (egg, coracidium, procercoid, plerocercoid, adult) in the life-cycle of the cestode Spirometra mansonoides, and of environmental lipids, have been examined by combinations of TEAE-cellulose and silicic acid column, silica gel thin-layer and SCOT column gas-liquid chromatography. Major lipids of all stages were triacylglycerols, cholesterol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, and phosphatidylcholine. Minor lipids were sterol esters, fatty acids, benzoquinones, partial glycerides phosphatidic acid, sphingolipids and lysolipids. Triacylglycerols decreased and cholesterol and phospholipids, particularly diphosphatidylglycerol and phosphatidylcholine, increased during embryogenesis (egg to coracidium). Neutral and phosphoglycerides had characteristic fatty acyl group patterns irrespective of life-cycle stage, except for procercoid lipids, which were unique in their content of branched and odd-numbered forms. The patterns seen in the total lipids of the various life-cycle stages were qualitatively similar to those of the environments of those stages, but were often quantitatively dissimilar.

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Ubiquinone-10 and rhodoquinone-10 were detected in stages of the life-cycle of a pseudophyllidean cestode, Spirometra mansonoides, by chromatographic, UV spectrophotometric, proton nuclear magnetic resonance spectrometric and electron impact mass spectrometric methods. Ubiquinone-10 was identified in 1-day-old eggs and coracidia, and rhodoquinone-10 in coracidia, plerocercoids and adult tapeworms. Tentative identification were also made of ubiquinone-10 in procercoids and rhodoquinone-10 in 10-day-old eggs. The roles of benzoquinones in helminth aerobic and anaerobic metabolism are discussed in relation to their distribution in stages of the S. mansonoides life-cycle.

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