Efficacy of tumor cell vaccine after incorporating monophosphoryl lipid A (MPL) in tumor cell membranes containing tumor-associated ganglioside

Murine B16 melanoma expresses the ganglioside. GM₃. GM₃ shed from tumor cells is immunosuppressive and promotes tumor growth¹. Reduction or elimination of the shed GM₃ could be therapeutic, and the anti-GM₃ antibodies may reduce and clear the shed ganglioside. To test this hypothesis, mice were challenged with tumor cells, with or without inducing anti-GM₃ antibody response. Since gangliosides are poor immunogens and T-cell independent antigens, an adjuvant (monophosphoryl lipid A (MPL), a non-toxic lipid A ofSalmonella), directed against B-cells, was employed. MPL was incorporated onto liposomes and into the surface membrane of B16 mouse melanoma cells; both are rich in GM₃. C57BL/6J mice immunized with MPL-liposomes or MPL-B16 cells responded with elevated levels of anti-GM₃ IgM. Non-immunized mice or mice immunized with B16 cells alone or ganglioside GM₃ alone (without MPL) elicited poor anti-GM₃ IgM response, confirming the GM₃'s immunologic crypticity and MPL's immunopotentiating effect. MPL's immunopotentiating effect was improved by coupling it to melanoma cell membranes C57BL/6J mice were immunized with irradiated B16 alone or MPL alone or MPL-conjugated irradiated B16. After three weekly immunizations, each mouse received a challenge dose of viable syngeneic B16. Neither MPL alone nor B16 alone had a significant effect on tumor growth or host survival; however, administration of MPL-conjugated B16 cells significantly prevented tumor growth and prolonged survival. Our results indicate that MPL-incorporated B16 cells augment the anti-GM₃ IgM response, which may reverse GM₃-induced immunosuppression by eliminating tumor-derived GM₃, and restore immunocompetence.     

Photoreactivation of UV damage in culturedDrosophila cells

Summary Cell survival and photoreactivation of 254 nm ultraviolet (UV) light damage in a wild typeDrosophila cell line was assayed by colony formation in liquid medium. F_o, F_q, and extrapolation number for the exponential portion of survival curves are 21 J/m², 3.6 J/m², and 1.5 for non-photoreactivated cells and 110 J/m², 11.2 J/m², and 1.3 for those exposed to photoreactivating light. Maximal photoreactivation occurs at the 100 J/m² region of the curve. At 10 and 50% survival, 75–80% of the UV damage was photoreactivable.     

Demonstration of vitamin D3 metabolism inmytilus edulis

Summary Radiolabeled vitamin D₃ was converted into several polar metabolites upon incubation with tissue homogenates from the common musselMytilus edulis. Chromatographic analysis indicated that the metabolites have chromatographic mobilities different from those of known standards. The results suggest that vitamin D₃ is metabolized in mussels via pathways that differ from the vertebrate systems.Acknowledgments. The authors thank Dr Pirjo Rantamäki for the mussels and F. Hoffmann-La Roche & Co. for supplying the vitamin D₃ metabolite standards. This work was supported by a grant from the Magnus Ehrnrooth Foundation to T. K.     

Progesterone regulation of implantation-related genes: new insights into the role of oestrogen

Genomic profiling was performed on explants of late proliferative phase human endometrium after 24-h treatment with progesterone (P) or oestradiol and progesterone (17β-E₂+P) and on explants of menstrual phase endometrium treated with 17β-E₂+P. Gene expression was validated with real-time PCR in the samples used for the arrays, in endometrium collected from early and mid-secretory phase endometrium, and in additional experiments performed on new samples collected in the menstrual and late proliferative phase. The results show that late proliferative phase human endometrium is more responsive to progestins than menstrual phase endometrium, that the expression of several genes associated with embryo implantation (i.e. thrombomodulin, monoamine oxidase A, SPARC-like 1) can be induced by P in vitro, and that genes that are fully dependent on the continuous presence of 17β-E₂ during P exposure can be distinguished from those that are P-dependent to a lesser extent. Therefore, 17β-E₂ selectively primes implantation-related genes for the effects of P. H. Dassen, C. Punyadeera: These authors contributed equally. Received 18 December 2006; received after revision 6 February 2007; accepted 8 March 2007     

The C4-dicarboxylate transport system ofRhizobium meliloti and its role in nitrogen fixation during symbiosis with alfalfa (Medicago sativa)

TheRhizobium meliloti C₄-dicarboxylate transport (Dct) system is essential for an effective symbiosis with alfalfa plants. C₄-dicarboxylates are the major carbon source taken up by bacteroids. Genetic analysis of Dct^– mutant strains led to the isolation of thedct carrier genedctA and the regulatory genesdctB anddctD. The carrier genedctA is regulated in free-living cells by the alternative sigma factor RpoN and the two-component regulatory system DctB/D. In addition, DctA is involved in its own regulation, possibly by interacting with DctB. In bacteroids, besides the DctB/DctD system an additional symbiotic activator is thought to be involved indctA expression. Further regulation ofdctA in the free-living state is reflected by diauxic growth of rhizobia, with succinate being the preferred carbon source. The tight coupling of C₄-dicarboxylate transport and nitrogen fixation is revealed by a reduced level of C₄-dicarboxylate transport in nitrogenase negative bacteroids.     

Hydroxylation of demethoxy-Q6 constitutes a control point in yeast coenzyme Q6 biosynthesis

Coenzyme Q is a lipid molecule required for respiration and antioxidant protection. Q biosynthesis in Saccharomyces cerevisiae requires nine proteins (Coq1p–Coq9p). We demonstrate in this study that Q levels are modulated during growth by its conversion from demethoxy-Q (DMQ), a late intermediate. Similar conversion was produced when cells were subjected to oxidative stress conditions. Changes in Q₆/DMQ₆ ratio were accompanied by changes in COQ7 gene mRNA levels encoding the protein responsible for the DMQ hydroxylation, the penultimate step in Q biosynthesis pathway. Yeast coq null mutant failed to accumulate any Q late biosynthetic intermediate. However, in coq7 mutants the addition of exogenous Q produces the DMQ synthesis. Similar effect was produced by over-expressing ABC1/COQ8. These results support the existence of a biosynthetic complex that allows the DMQ₆ accumulation and suggest that Coq7p is a control point for the Q biosynthesis regulation in yeast. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Received 04 September 2008; received after revision 22 October 2008; accepted 23 October 2008     

Drosophila melanogaster does not dealkylate [14C]sitosterol

Summary Drosophila melanogaster was unable to dealkylate and convert [¹⁴C]sitosterol to cholesterol and no evidence was found for conversion of [¹⁴C]desmosterol to cholesterol. Therefore,D. melanogaster is incapable of dealkylating and converting C₂₈ and C₂₉ phytosterols to cholesterol.The authors thank O. J. Duncan III, and H. S. Symonds for technical assistance. Mention of a company name or proprietary product does not imply endorsement by the U.S. Department of Agriculture.     

Pinitol,a larval growth inhibitor forHeliothis zea in soybeans

Summary A search for insect growth inhibitors in methanol extracts of soybean leaves resulted in isolation of pinitol. Pinitol caused a 50% reduction in weight gain (ED₅₀) ofHeliothis zea larvae at about 0.7% when added to a synthetic diet. Although myo-inositol is a normal component of the insect diet, it also caused growth inhibition at higher concentrations; ED₅₀4%.The authors are indebted to R.J. Molyneux for a reference sample of pinitol and to J. Baker for aid with the bioassay. Reference to a company and/or product named by the Department is only for purposes of information and does not imply approval or recommendation of the product to the exclusion of others which may also be suitable.     

Invertebrate neuropeptides resembling vasotocin and some analogues: Synthesis and pharmacological properties

Summary The solid phase synthesis of three invertebrate vasopressin-oxytocin homologs: AVP-like factor, F₁ ¹, ([Leu², Thr⁴] AVT)² isolated from subesophageal and thoracic ganglia ofLocusta migratoria ³, Arg-conopressin-S⁴. ([Ile², Arg⁴] AVT), Lys-conopressin-G⁴ ([Phe², Arg⁴] LVT), both isolated from the venom of fish-hunting marine snails of the genusConus and six of their analogues is reported. These analogues are: [Arg⁴] AVT, [Ile²] AVT, [Leu²] AVT, [Phe², Arg⁴] AVT, [Arg⁴] LVT and [Ile², Arg⁴] LVT. All peptides were tested for antidiuretic and vasopressor activities.     

Furospongolide,a new C21 furanoterpene from a marine organism

Summary The structure of a new linear C₂₁ furanoterpene, furospongolide (1), obtained from the marine spongeDysidea herbacea, was determined by spectral means.We thank Professor J. Vacelet for the identification and Dr Loya and Mr Benayahu for the collection of the sponge.     

The possible involvement of protein kinase C and phospholipase A2 inHydra tentacle regeneration

The participation of protein kinase C (PKC) in the regeneration of tentacles ofHydra vulgaris was studied. Regeneration was induced by 1,2-sn-dioctanoyl-glycerol (diC₈) and the novel diterpenoidic diacylglycerol verrucosin B (VB), a potent PKC activator extracted from marine sources. VB substantially increasedHydra average tentacle number (ATN) at concentrations 10,000 times lower than those needed for diC₈ to exert an analogous effect. When both synthetic and natural VB analogues were tested, the structure/activity relationship found inHydra tentacle regeneration was identical to that known for DAG-induced activation of PKC in vitro. VB-induced increase of ATN was strongly counteracted by the PKC inhibitors sphingosine and A3, but was not synergic with a tenfold increase of extracellular Ca²⁺ concentration or with an increase of intracellular Ca²⁺ concentration obtained either with the ionophore A23187 or with thapsigargin. This suggested the involvement of a non-Ca²⁺-dependent PKC in VB-triggeredHydra tentacle regeneration. The involvement of phospholipase A₂ (PLA₂) activation inHydra regenerative processes was studied using the novel site-specific inhibitor of the enzyme, oleyloxyethylphosphorylcholine (OOPC), which brought about a striking inhibition of ATN in the low molar range. This effect was reversed by arachidonic acid (AA), while an enhancement of ATN was also observed with an inhibitor of AA uptake from membrane phospholipids, thus suggesting that PLA₂-catalysed liberation of AA is involved inHydra tentacle regeneration. OOPC also blocked verrucosin B-induced PKC-mediated enhancement of ATN, thus suggesting that this effect is also mediated by PLA₂ activation. ATN was increased also by compound 48/80, a direct activator of pertussis toxin-sensitive GTP-binding proteins, and this effect was counteracted by pertussis toxin pretreatment. None of the known AA cascade inhibitors exhibited an effect on ATN comparable to that exerted by OOPC, but, surprisingly, the cycloxygenase inhibitor indomethacin strongly enhanced ATN, thus suggesting that prostanoids might effect a negative control onHydra regenerative processes. This represents the first attempt so far reported to study the implication of more than one biochemical pathway as a signalling event in the hydroid regenerative processes.     

An increase in the influx of calcium ions into cilia induces thigmotaxis inParamecium caudatum

To understand the role of calcium ions in thigmotaxis inParamecium caudatum, the effects of caffeine, ruthenium red and lanthanum (LaCl₃) on thigmotaxis were examined. Thigmotaxis in the CNR mutant, which lacks voltage-dependent Ca²⁺-channels in the ciliary membrane, was also examined. Ruthenium red and LaCl₃ suppressed thigmotaxis inP. caudatum, while caffeine enhanced it. The CNR mutant showed hardly any thigmotaxis. It can be thought that an increase in Ca²⁺ influx and the intraciliary concentration of Ca²⁺ ions induces thigmotaxis inParamecium.     

Luffolide,a novel anti-inflammatory terpene from the spongeLuffariella sp.

Summary Luffolide (4) is a minor metabolite of the spongeLuffariella sp. from Palau. The structure of luffolide was determined by single crystal X-ray analysis. Luffolide is relatively unstable and undergoes a complex cyclization reaction to give the hexacyclic products5 and6. Luffolide (4) has some of the anti-inflammatory properties of manoalide (1): this may help to define the chemical reaction between manoalide (1) and phospholipase A₂.All crystallographic calculations were done on a PRIME 9950 computer operated by the Cornell Chemistry Computing Facility. Principal programs employed were: FOBS, a data reduction program by G.D. Van Duyne, Cornell University, 1987; MULTAN 80, and RANTAN 80, systems of computer programs for the automatic solution of crystal structures from X-ray diffraction data (locally modified to perform all Fourier calculations including Patterson syntheses) written by P. Main, S. E. Hull, L. Lessinger, G. Germain, J. P. Declercq and M. M. Woolfson, University of York, England, 1980 BDLS, an, anisotropic block diagonal least squares refinement written by K. Hirotsu, E. Arnold, and G. D. Van Duyne, Cornell University, 1987; PLUTO 78, a locally modified crystallographic illustration program by W. D. S. Motherwell, Cambridge Crystallographic Data Centre, 1978; and BOND, a program to calculate molecular parameters and prepare tables written by K. Hirotsu and G. Van Duyne, Cornell University, 1985.Acknowledgment. We thank the Government of the Republic of Palau for a scientific research permit. We thank Dr Klaus Rützler, Smithsonian Institution, Washington, D.C. for identifying the sponge and Mary Kay Harper for performing additional bioassays. This research was supported by grants from the Sea Grant College Programs of California [Projects R/MP-30 to DJF) and R/MP-31 (to RSJ)] and New York (to JC) and the National Institutes of Health (CA 24487 to JC).     

Interchange trisomics in pearl millet

Summary In the progeny of interchange heterozygotes ofPennisetum typhoides, 2 interchange trisomic plants were obtained. These were selfed over 2 generations and the cytology of the parents, s₁ and s₂ plants was studied. The types of multiple associations in the s₁ and s₂ generations differed from those of the parent. A significant decrease in mean chiasma frequency was noted in s₁ and s₂.Acknowledgment. The author is grateful to Prof. em. J. V. Pantulu, Department of Botany, Andhra University, Waltair, for his suggestions and encouragement.     

Influence of phosphorus supply and light intensity on mycorrhizal response inPisum-Rhizobium-Glomus symbiosis

The influence of mycorrhizal colonization withGlomus mosseae on parameters of N₂ fixation and plant growth was studied in pot experiments with pea plants (Pisum sativum L.) infected withRhizobium leguminosarum and supplied with varied levels of phosphorus (P) and nitrogen (N). Reduced light intensities were used to evaluate the dependence of the microsymbionts on assimilate supply. In plants grown with low P supply, mycorrhization increased the concentration of P in shoots, and thus N₂ fixation. Reduced light intensity significantly depressed mycorrhizal colonization and nodule growth in low-P plants. When P supply did not limit plant growth and N₂ fixation, however, the percentage of mycorrhizal colonization was reduced due to the higher P status, and the microsymbionts were not impaired by low light intensities. To maximize carbohydrate supply, another experiment was carried out at high light intensity of 900 mol m^–2s^–1 and with non-limiting P supply. Nitrogen fertilization, given as starter N, enhanced plant growth, but delayed nodule formation. Towards flowering, nodulation rapidly increased, but less so inGlomus inoculated plants. After 28 days mycorrhizal plants were lower in shoot dry weight, nodule dry weight and nitrogenase activity. The results suggest that under many, but not all, environmental conditions the host plant is able to restrict mycorrhizal colonization and, thus, to prevent impairment ofRhizobium symbiosis.deceased in May 1994     

Influence of oxygen concentration on development ofDrosophila melanogaster

Summary 1st, 2nd, and early 3rd instarDrosophila larvae are extremely sensitive to 100% O₂ or 75% O₂/25% N₂ (at atmospheric pressure) whereas eggs, late 3rd instar larvae, and pupae are relatively insensitive under our exposure conditions. Eclosing flies exposed to an O₂ enriched environment consistently possessed 2 eye abnormalities: dark eye color and altered eye shape.Supported by NSF-URP grant SP1782684 and a Summer Faculty Fellowship to Harry Nickla.     

Characterization of the host-specific toxins produced byHelminthosporium sacchari,the causal organism of eyespot disease of sugarcane

Summary Investigation of the host-specific toxin complex fromH. sacchari has led to the isolation of 3 isomeric glycosidic components C₃₉H₆₄O₂₂, each active at 2×10^–11 moles. The 3 isomers consist of 4 galactose units linked to an aglycone residue C₁₅H₂₄O₂.Acknowledgments. The Boyce Thompson-Cornell group thanks J.F. Rissler, University of Maryland, A.K. Bose, Stevens Institute of Technology, R. Barker and A. Serriani, Cornell University, and C. Grinnalds and J. Golay, Boyce Thompson Institute for help with various aspects of this work. Supported in part by a grant to V.M. from the US Department of Agriculture (8100720). The Zürich group thanks Dr G.A. Strobel, Department of Botany and Microbiology, Montana State University, Bozeman, for supplying a potent toxin-producing strain (M 36), a susceptible clone of sugarcane (51 NG 97), and a reference sample of helminthosporoside, Dr. K. Hostettmann and Mme M. Hostettmann-Kaldas, Pharmazeutisches Institut ETH Zürich, for assistance in developing the DCC separation and Sandoz A.G., Basel, for financial support.     

Rauwolfia alkaloids,XVI. Deserpidine,a new alkaloid fromRauwolfia canescens

Zusammenfassung AusRauwolfia canescens wurde Deserpidin, C₃₂H₃₈O₈N₂, isoliert und eine Konstitutionsformel für dieses neue Alkaloid vorgeschlagen.

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Communication XV,C. F. Huebner et al., J.A.C.S. (in press).

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From lecture given at Columbia University, New York, January 12th, 1955.     

The effect of aspartate on the electroretinogram of the vertebrate retina

Zusammenfassung Es wird gefunden, dass nach Applikation des zur Perfusionsflüssigkeit zugefügtenl-Aspartats auf die isolierte Froschretina eine auffallende Hemmung dera ₂- undb-Welle auftritt, dies jedoch ohne sichtbare Veränderung der Form und Amplitude des «early and late receptor potential».     

Luffariellolide,an anti-inflammatory sesterterpene from the marine spongeLuffariella sp.

Summary Luffariellolide (2) is a sesterterpene from the Palauan spongeLuffariella sp. that has useful anti-inflammatory properties. In contrast with the irreversible action of manoalide (1) on phospholipase A₂, luffariellolide (2) is a slightly less potent but partially reversible PLA₂ inhibitor.30 December 1986Acknowledgment We thank Edward Luedtke, Elise Clason and Ellen Snideman for performing some of the assays reported above. The sponge was identified by Dr. Klaus Rützler, Smithsonian Institution, Washington, D.C. The research was supported by grants from Allergan Pharmaceuticals and the California Sea Grant College Program (Projects R/MP-30 and R/MP-31).