[allergy and lectins: action between ige-mediated histamine release and glycoproteins from viscum album l. (mistletoe)].low-molecular constituents from viscum album (toxic) release, in irritatively toxic manner, histamine from human leukocytes without destroying the cells (cytotox test). this histamine release is prevented by preincubation with viscum lectins. the viscum lectin blocks the fc-portion of allergen-specific ige against anti-ige [125i]. lectin also inhibits the allergen-specific histamine release from human leukocytes occurring through ige; this can be demonstrated on leukocytes from patients with ato ...197888141
affinity chromatography of human serum proteins using matrix bound lectins from viscum album and vicia faba.the d-galactose specific lectin from viscum album and the d-mannose specific lectin from vicia faba react with serum proteins which contain the corresponding carboyhydrate moieties. by affinity chromatography of human serum using the combination of insolubilized lectins coupled to sepharose it is possible to fractionate serum proteins in 3 groups: 1. proteins which react with both of the lectins; 2. proteins which react only with one of the lectins; 3. proteins which do not display any affinity ...1979525149
[isolation and characterization of mistletoe extracts (viscum album l.). ii. effect of agglutinating and cytotoxic fractions on mouse ascites tumor cells].lectin from mistletoe (viscum album l.) was studied for its relations with the toxins from viscum album, ascites tumor cells of mouse, and human immunoglobulins. using affinity chromatography on glutaraldehyde-crosslinked igg (human) from viscum crude extract, a fraction was isolated which exhibited full agglutination capacity and high toxicity. the supernatant showed no agglutination capacity but a strong toxic effect on mouse ascites tumor cells. this toxic effect could not be influenced by fu ...1977560094
the lectin from viscum album l. purification by biospecific affinity chromatography.a lectin from viscum album which specifically binds to d-galactose was isolated by affinity chromatography on o-lactosyl-, o-galactosyl-polycarylamide or hydrolized sepharose 4 b. some serological and physicochemical properties of the agglutination are reported.1978563801
enhancement of the cytotoxicity of mistletoe lectin-1 (ml-1) by high ph or perturbation in golgi functions.we have studied the cytotoxicity of mistletoe lectin-1 (ml-1), a cytotoxic protein produced by viscum album, in cho and v79 cells and in mutant cell lines altered in golgi functions or in endosomal acidification. in wild-type cho cells, cytotoxicity of ml-1 was greatly enhanced by ammonium chloride or nigericin. a cho mutant defective in endosomal acidification (dmpr-2), which is resistant to diphtheria toxin, modeccin and pseudomonas aeruginosa exotoxin a and hypersensitive to ricin, showed inc ...19911910176
induction of tumor necrosis factor expression by a lectin from viscum album.a purified lectin (mli) from viscum album was used to test whether peripheral monocytes from human blood can be activated for the production of tumour necrosis factor (tnf). cytotoxic activity was detected in the supernatant of mli-stimulated monocyte cultures. this cytotoxic activity was completely inhibited by monoclonal antibodies to tnf alpha. small amounts of soluble tnf protein were measured in a tnf alpha-specific enzyme-linked immunospecific assay system. strong expression of tnf alpha m ...19912044082
a viscum album oligosaccharide activating human natural cytotoxicity is an interferon gamma inducer.commercial viscum album extract helixor-m contains a dialysable oligosaccharide (hm-bp) that activates natural killer (nk) cytotoxicity against k562 tumour cells when preincubated with human peripheral blood mononuclear cells (pbmc) for 72 h. the activated effector cells were exclusively found in the monocyte/macrophage subpopulation. however, when peripheral non-adherent cells (pnac) were preincubated with hm-bp for 72 h the nk cytotoxicity of cd56+cd3- nk cells was activated. this discrepancy ...19902124513
effect of a preparation from viscum album on tumor development in vitro and in mice.the effect of iscador, a commercial preparation made from viscum album was studied on several cell lines using in vitro tissue culture as well as tumor-bearing animals. iscador was found to be cytotoxic to animal tumor cells such as dalton's lymphoma ascites cells (dla cells) and ehrlich ascites cells in vitro and inhibited the growth of lung fibroblasts (lb cells), chinese hamster ovary cells (cho cells) and human nasopharyngeal carcinoma cells (kb cells) at very low concentrations. moreover, a ...19902345458
chemical specificity of effector cell/tumor cell bridging by a viscum album rhamnogalacturonan enhancing cytotoxicity of human nk cells.the component in viscum album extract iscador-m enhancing the nk cytotoxicity of human cd56+cd3- nk cells (87-95% enrichment) in cocultures with k562 tumor cells and increasing the formation of nk cell/tumor cell conjugates was identified as a rhamnogalacturonan. both activities were abolished by treatment of v. album extract with poly-alpha-d-galacturonidase and alpha-rhamnosidase and both activities were inhibited in the presence of galacturonic acid and acetylated rhamnose (6-deoxymannose). i ...19902407685
[studies on the effect of mistletoe extract on the chemotactic activity and on chemiluminescence of polymorphonuclear leukocytes in vitro].in the present study, the chemotactic activity of human polymorphonuclear granulocytes was measured using the tripeptide n-f-met-leu-phe and different concentrations of extracts of viscum album as chemotactic stimuli. it turned out that the extracts have the capability of stimulating chemotaxis up to 30% of the formylated tripeptide. incubation of isolated granulocytes for 20 minutes in medium alone prior to assessment of chemotaxis results in a 20% loss of chemotactic activity as compared to th ...19892813581
pneumocystis carinii: surface reactive carbohydrates detected by lectin probes.pneumocystis carinii obtained from rat lungs (rlh) and in vitro culture (rtc) were reacted with a panel of 14 fluorescein isothiocyanate conjugated lectins. percentage fluorescence and fluorescent intensity were determined for both trophic and cyst forms. all rlh and rtc derived organisms bound strongly concanavalin a (con a), and wheat germ agglutinin (wga). however, differences in soybean agglutinin (sba) binding between rlh and rtc organisms was observed. different subsets of the organism bou ...19883142787
the site of action of the a-chain of mistletoe lectin i on eukaryotic ribosomes. the rna n-glycosidase activity of the protein.the site of action of the a-chain of mistletoe lectin (ml-a) from viscum album on eukaryotic ribosomes was studied. treatment of rat liver ribosomes with ml-a, followed by treatment of the isolated rrna with aniline, caused the release of a fragment with about 450 nucleotides from 28 s rrna. further analysis of nucleotide sequences of this fragment revealed that the aniline-sensitive site of phosphodiester bond was between positions a-4324 and g-4325 in 28 s rrna. these results indicate that ml- ...19883360143
mediation of human nk-activity by components in extracts of viscum album.viscum album extracts (iscador) were investigated for their potency to influence nk cytotoxicity in vitro. in vitro short term cytotoxicity assays (4 h) with human peripheral mononuclear cells (pmnc) and human k 562 tumor cells showed a drastic enhancement of nk cytotoxicity in the presence of v. album extracts. the presence of the v. album components during tumor cell lysis was essential since preincubation of pmnc with v. album extract followed by thorough washing did not lead to enhancement o ...19873583510
effects of lectin i from mistletoe (ml i) and its isolated a and b chains on human mononuclear cells: mitogenic activity and lymphokine release.the interaction of lectin i from mistletoe (viscum album) (ml i) and its isolated a and b chains with mononuclear cells from healthy human donors was investigated with respect to proliferation capacity (mitogenicity) and monokine/lymphokine factor (msf) production. the factor produced was studied by means of the electrophoretic mobility inhibition assay using guinea pig macrophages as indicator cells. ml i and its b chain exhibited comparable inhibitory effects on the proliferation of mononuclea ...19873671448
natural killer and antibody-dependent cell-mediated cytotoxicity activities and large granular lymphocyte frequencies in viscum album-treated breast cancer patients.20 breast cancer patients received a single intravenous infusion of iscador, a mistletoe (viscum album l.) extract. natural killer (nk) and antibody-dependent cell-mediated cytotoxicity (adcc) activities as well as the number of large granular lymphocytes (lgl) were investigated in their peripheral blood at various times. six hours after the start of the infusion, significant decreases and 24 h later, significant increases in nk/adcc activities and lgl frequencies were observed. these responses ...19863951791
heterophile agglutinins with a broad-spectrum specificity. vi. the nature of cell surface receptors for the agglutinins present in seeds of amaranthus caudatus, maclura aurantica, datura stramonium, viscum album, phaseolus vulgaris and moluccella laevis. 19704249809
isolation and characterization of viscotoxin 1-ps from viscum album l. ssp. austriacum (wiesb.) vollmann, growing on pinus silvestris. 19744417993
[free amino acid content of viscum album l. berries parasitizing the pinus silvestris l. and pinus nigra arnold var. austriaca]. 19675613334
[research on the constituents of the fruit of the loranthus europaeus jacq. (viscum album). i. total fatty acid content and free amino acid content of the pericarp]. 19655882424
the lectin from viscum album l.--isolation, characterization, properties and structure. 19806771171
determination of 5-methylcytosine from plant dna by high-performance liquid chromatography.the relative amounts of the five nucleosides (deoxycytidine, 5-methyldeoxycytidine, deoxyadenosine, deoxyguanosine and thymidine) in the dna of nine plant species, one plant satellite dna, and one animal species were determined by high performance liquid chromatography. the method allows the clean separation of the nucleosides from 10 microgram samples with 15 min. the following values for the proportion of methylated cytosines among all cytosines were obtained: lobularia maritima 18.5%, nicotia ...19817272310
isolation of viscotoxins. cytotoxic basic polypeptides from viscum album the course of cytotoxicity-directed fractionation of extracts from viscum album l., it appeared that crude viscotoxin, a basic polypeptide fraction, is responsible for cytotoxic properties of the plant examined. separation of this fraction by ion exchange chromatography on carboxymethylcellulose led to isolation of five cytotoxic components. four of them, named viscotoxins i, ii, iii and ivb were obtained as homogeneous substances. the isolated polypeptides exhibited cytotoxic activity agains ...19807450674
expression of galactoside-specific endogenous lectins and their ligands in human oral squamous cell carcinoma.human endogenous lectins have a wide spectrum of biological functions. the present study analyses the expression of beta-galactoside specific and n-acetyl-d-galactosamine specific endogenous lectins in oral squamous cell carcinomas using biotinylated neoglycoproteins. the expression pattern of beta-galactosyl-containing glycoconjugates or ligands of beta-galactoside specific lectins in these tissues was also studied using an endogenous biotinylated lectin, the human 14-kda lectin. for comparison ...19947522955
glycoconjugate expression of chondrocytes and perichondrium during hyaline cartilage development in the rat.alterations in the expression of glycoconjugate structures during cartilage development in the chondrocranium, nasal skeleton, meckel's cartilage, limb buds, vertebral bodies and ribs were investigated comparatively in 13 to 21-d-old rat embryos. the binding patterns of 24 biotinylated lectins were analysed in serial sections and compared with results obtained using histochemical methods. proteoglycan distribution, assessed by conventional staining procedures, was not associated with lectin bind ...19957591987
[h2o2 generation and human neutrophil aggregation as affected by lectins].the effects of eight plant lectins on human neutrophils aggregation and h2o2 release were studied. both processes were stimulated by lectins from viscum album, triticum vulgaris, phaseolus vulgaris and canavalia ensiformis while lectins from solanum tuberosum, sambucus nigra and glycine mas displayed only aggregating activity and arachis hypogaea lectin was not effective. heating (46 degrees c) and uv-radiation during 4-5 min were found to suppress completely h2o2 release from neutrophils keepin ...19957557235
isolation and properties of three lectins from mistletoe (viscum album l.).three lectins have been isolated from an extract of mistletoe (viscum album) by affinity chromatography on partially hydrolysed sepharose and human immunoglobulin- sepharose. the lectins differ in molecular weight and sugar specificity (lectin i, mol.wt. 11500, d-galactose-specific; lectin ii, mol.wt. 60000, both d-galactose- and n-acetyl-d-galactosamine-specific; lectin iii, mol. wt. 50000, n-acetyl-d-galactosamine-specific). all three lectins react with human erythrocytes without specificity f ...19817316963
characterization of glycoconjugate expression during development of meckel's cartilage in the rat.the staining patterns of 24 biotinylated lectins were analyzed in serial sections of the mandible of 13- to 21-day-old rat embryos by means of the avidin-biotin-peroxidase method. a ubiquitous distribution of binding sites was demonstrated after incubation with con a (canavalia ensiformis), dsl (datura stramonium; except bone matrix), and wga (triticum vulgare). ecl (erythrina cristagalli), gsl i (griffonia simplicifolia), sja (saphora japonica), vvl (vicia villosa), dba (dolichus biflorus), uea ...19957717533
the interactions of anti-mli monoclonal antibodies with isoforms of the lectin from viscum album.monoclonal antibodies (mab) reacting with native (ta5, tb12) and denatured (t33, t35) plant toxin mistletoe lectin i (mli) from viscum album have been obtained. the interaction between mabs and native toxin with ml isoforms (mlii, mliii) has been investigated. an immunological cross-reaction has been shown to take place for mab ta5 (anti-a-chain of mli) between mlii and mliii isoforms of toxin. ta5 has not inhibited enzyme activity of the a-chain in a rabbit reticulocyte cell-free system. tb12 h ...19957721340
interaction between dna and viscotoxins. cytotoxic basic polypeptides from viscum album l.cytotoxic viscotoxins i, ii, iii and ivb protect the native structure of dna against thermal denaturation. viscotoxin ivb-dna complexes, obtained by direct mixing, were studied in detail by the techniques of thermal denaturation of dna and circular dichroism (cd). the binding of viscotoxin ivb to dna is principally ionic. this interaction results in dna segments of different thermal stability, probably due to the cooperativity of the binding process. cd studies disclosed that conformation of dna ...19807192684
[reactions of in vitro cultures of human fibroblasts, of hela-cells and of murine l-cells on application of a drug from viscum album l. (author's transl)].helixor, a drug from the mistletoe, reduces in vitro the growth of the permanent human hela-cell line and the growth of the permanent mouse l-cell line more than the growth of human fibroblast strains with limited capacity of propagation in vitro.19807192110
lectins as probes to pneumocystis carinii surface glycocomplexes.the binding characteristics of a panel of commercially available fitc-conjugated lectins to pneumocystis carinii (pc) were assessed by fluorescence microscopy and flow cytometry. rat pc obtained from infected lung homogenates were incubated with fitc-conjugated lectins in a series of concentrations, counterstained with propidium iodide, and analyzed for percent fluorescence and fluorescence intensity. all organisms bound concanavalin a and wisteria floribunda agglutinin, 2 representatives of the ...19892785201
activation of natural killer cell cytotoxicity of human blood monocytes by a low molecular weight component from viscum album extract.viscum album extracts (helixor) were investigated for their potency to influence natural killer cell (nk) cytotoxicity of human peripheral blood mononuclear cells (pbmc) in vitro. the samples investigated were unable to enhance nk cytotoxicity in pbmc/tumor cell co-cultures by direct short-term mediation but nk cytotoxicity of human pbmc was strongly stimulated when pbmc were pre-incubated for 72 h with a partly purified fraction (hm-bp) derived from extracts of v. album mali. stimulation of nk ...19892624609
phenotype-associated lectin-binding profiles of normal and transformed blood cells: a comparative analysis of mannose- and galactose-binding lectins from plants and human serum/placenta.surface glycoconjugates of normal and transformed blood cells are commonly characterized by plant lectins. to infer physiological significance of protein-carbohydrate interactions, mammalian lectins are obviously preferable as research tools. so far, human serum lectins have not been used to assess their binding to immunophenotyped human normal or transformed blood cells. thus, our study combines two groups of lectins with different specificity from plant and human sources. besides concanavalin ...19947889985
[the effects of plant preparations on cellular functions in body defense].two preparations of echinacea purpurea and a preparation of eleutherococcus senticosus increased the in vitro phagocytosis of candida albicans by granulocytes and monocytes from healthy donors by 30-45%. the chemotactic migration of granulocytes in the boyden chamber was increased by 45% with an echinacea purpurea extract. the two herbal preparations had no effect in either direction on intracellular killing of bacteria or yeasts. echinacea and eleutherococcus preparations did not induce in vitr ...19948192704
antitumorous and immunomodulatory effects of the viscum album l. preparation isorel.there are numerous data on the immunostimulative and antitumorous activity of various viscum album tissue extracts. isorel (novipharm, austria) is one of these compounds. we found that in mice an increased number of plaque-forming cells to sheep red blood cells (srbc) followed the injection of isorel together with srbc. further, survival time of a foreign skin graft was shortened if isorel was applied at the correct time. finally, suppressed immune reactivity in tumorous mice recovered following ...19938233280
[use of ferritin conjugates of a lectin from mistletoe (viscum album l.) for the electron microscopic localization of cell surface receptors].ferritin conjugates of a lectin from mistletoe (viscum album l.) were used for the electron-microscopic demonstration of carbohydrate receptors on the cell surface of human erythrocytes and murine tumor cells. human a1 erythrocytes showed only a slight focal binding of ferritin. cells of the mouse ascites tumor strain l 1210 were labelled very tightly on their surface and incorporate the ferritin by pinocytosis. furthermore they showed cytotoxic changes in their ultrastructure. in the presence o ...1978752206
chemical modification studies on the d-galactopyranosyl binding lectin from the mistletoe viscum album l.the role of amino, sulfhydryl, disulfide, carboxyl, phenolic, imidazole and indole groups on the agglutination of human erythrocytes by the lectin from viscum album has been determined using specific chemical modification techniques. the results indicate that tyrosine residues participate in the hemagglutination reaction. subunits of the lectin possess only reduced hemagglutinating ability.1979550670
molecular mechanism of inhibition of mammalian protein synthesis by some four-chain agglutinins. proposal of an extended classification of plant ribosome-inactivating proteins (rrna n-glycosidases).the four chain agglutinins from abrus precatorius, viscum album and ricinus communis promote depurination of the 28 s rrna from rabbit reticulocyte ribosomes characteristic of the common ribosome-inactivating proteins (rips). these agglutinins inhibited mammalian protein synthesis at nanomolar concentrations but they do not affect plant protein synthesis under the same conditions. therefore, they should also be considered as true rips but of a new class, the four-chain rips. an extended classifi ...19938354410
viscum album agglutinin-induced aggregation of blood cells and the lectin effects on neutrophil function.extracts from mistletoe enjoy a large popularity in central europe as an unconventional treatment modality for cancer, warranting scientific efforts with defined components to delineate any potential benefit. the galactose-specific lectin from viscum album (vaa), known to exhibit immunomodulatory and ensuing antitumoral capacities in animal model systems, was shown to aggregate human blood cells in the following order: neutrophils, mononuclear cells--thrombocytes and erythrocytes. to contribute ...19957647287
enhancement of mhc-unrestricted cytotoxic activity of human cd56+ cd3- natural killer (nk) cells and cd3+ t cells by rhamnogalacturonan: target cell specificity and activity against nk-insensitive targets.rhamnogalacturonan-mediated enhancement of mhc-unrestricted cytotoxicity was studied with freshly isolated cd56+cd3- natural killer (nk) cells, interleukin-2 (il-2)-activated cd56+ lymphokine-activated killer (lak) cells und il-2/anti-cd3-activated t cells as effector cells using nk-sensitive and nk-insensitive tumor cells as targets. the rhamnogalacturonan fractions im, ip, and iq were prepared from commercially available extracts of viscum album. the dose/response relation of im, ip, and iq de ...19947514604
isolation and characterization of viscumin, a toxic lectin from viscum album l. (mistletoe).a toxic protein, viscumin, was isolated from extracts of mistletoe by affinity chromatography on acid-treated sepharose 4b. viscumin was selectively bound to the column and could be eluted with lactose. it migrated in polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate corresponding to mr = 60,000. in addition, two bands migrating corresponding to mr = 29,000 and 32,000 were found. after treatment with 2-mercaptoethanol, only 2 bands (mr = 29,000 and 34,000) were found. ...19827142144
influence of carbohydrates on the cytotoxicity of an aqueous mistletoe drug and of purified mistletoe lectins tested on human t-leukemia cells.partially and highly purified lectins from viscum album l. (mistletoe) cause a dose-dependent decrease of viability of human leukemia cell cultures, molt-4, after 72 h treatment. the lc50 of the partially purified lectin was 27.8 ng/ml, of the highly purified lectin 1.3 ng/ml. compared to the highly purified lectin a 140-fold higher protein concentration of an aqueous mistletoe drug was required to obtain similar cytotoxic effects on molt-4 cells. cytotoxicity of the highly purified lectin was p ...19892775329
carbohydrate-binding proteins (plant/human lectins and autoantibodies from human serum) as mediators of release of lysozyme, elastase, and myeloperoxidase from human neutrophils.analysis of cell surface glycosylation not only provides information about cell properties such as their state of differentiation or histogenetic lineage. the carbohydrate chains also provide potentially functional binding sites to endogenous carbohydrate-binding proteins. this interaction can elicit consequent signalling processes. because of the importance of neutrophils in the host defence system, we monitored the effect of the binding of such sugar receptors to their cell surface on the rele ...19958570910
an investigation of some turkish herbal medicines in salmonella typhimurium and in the comet assay in human lymphocytes.medicinal plants play a major role in the life of turkish people and of late medicinal plant usage has increased in many countries. green plants in general contain mutagenic and carcinogenic substances, but there is little information about the biological activities of herbal medicine. in the present study, therefore, various turkish medicinal herbs were investigated for their genotoxic potential in the salmonella typhimurium microsomal activation assay and the alkaline single cell gel electroph ...19968875742
a plant lectin derived from viscum album induces cytokine gene expression and protein production in cultures of human peripheral blood mononuclear cells.a plant lectin from viscum album (ml-i) has been shown to increase the number and cytotoxic activity of natural killer cells and to induce antitumor activity in animal models. however, the mechanisms underlying the effects of ml-i on natural host defenses are unknown. after 24 h incubation of peripheral blood mononuclear cells in the presence of 10 and 1 ng/ml of ml-i, mrna expression and secretion of a panel of cytokines were evaluated by reverse polymerase chain reaction and by elisa, respecti ...19958933823
differentiation of rodent trypanosomes of the subgenus herpetosoma by lectins.trypomastigote forms of trypanosoma microti, t. evotomys, t. grosi, t. musculi, and t. lewisi and trypomastigote and epimastigote forms of t. acomys were differentiated using 34 lectins and the aminoff test for n-acetylneuraminic acid (nana). twelve of the lectins failed to agglutinate any of the above species. the number of lectins which agglutinated each species differed; t. mciroti, t. evotomys, t. grosi, t. musculi, t. lewisi and t. acomys (trypomastigote and epimastigote forms) were aggluti ...19892617032
[the agglutination of human erythrocytes and mouse ascites tumor cells by extracts from mistletoe (viscum album l.)]. 1976983598
affinity chromatography of human serum proteins using matrix bound lectin from viscum album l.the d-galactose specific lectin from viscum album l. reacts with serum proteins that contain the corresponding d-galactopyranosyl residues. by affinity chromatography of human serum on lectin-sepharose igm, alpha 2-macroglobulin, haptoglobin and beta-lipoprotein were quantitatively retained. only parts of iga, igg and transferrin were retarded. the other serum proteins are unbounded as albumin, beta 1 a- and beta 1 c-globulin.1979421816
modulation of cytotoxicity and enhancement of cytokine release induced by viscum album l. extracts or mistletoe lectins.cytotoxic effects of viscum album l. (mistletoe) extracts and mistletoe lectins were studied by light and electron microscopy. the first events observed were membrane perforation and protrusions typical for apoptosis. inhibition of molt 4 cell growth was obtained with lectin concentrations in the pg/ml range as long as cells were cultured in serum-free medium. under this condition, mistletoe lectin-iii was about 10 times more cytotoxic than mistletoe lectin-i; mistletoe lectin-ii was in between. ...19979179359
differential response of the epidermal growth factor receptor tyrosine kinase activity to several plant and mammalian lectins.biosignalling via lectins may involve modulation of protein kinase activities. this aspect of the biological action of mammalian and plant lectins has been investigated for their effect on the activity of the isolated epidermal growth factor receptor (egfr). the constitutive tyrosine kinase activity of the epidermal growth factor receptor from rat liver, isolated by calmodulin-affinity chromatography, was activated by concanvalin a (cona), and wheat germ agglutinin (wga) to a similar extent as t ...19957770063
biochemical characterization of a component in extracts of viscum album enhancing human nk cytotoxicity.enhancement of human nk cytotoxicity in the presence of fresh viscum album extract and some commercial v. album extracts iscador correlated strictly with an increased formation of lytic effector cell/k562 tumor cell conjugates in the single-cell assay. both activities were completely destroyed by pretreatment of v. album extracts with pectinase, hemicellulase, amyloglucosidase and alpha-glucosidase, but not with proteases and rnase, i.e., the activities are linked to a polysaccharide. the active ...19892708032
synergistic action of a plant rhamnogalacturonan enhancing antitumor cytotoxicity of human natural killer and lymphokine-activated killer cells: chemical specificity of target cell recognition.the spontaneous natural killer (nk) and lymphokine-activated killer (lak) cytotoxicity of highly purified cd56+cd3- nk cells (90 to 95%) against nk-sensitive and nk-insensitive target cells was drastically enhanced when a rhamnogalacturonan contained in a commercially available viscum album extract was present during 4-h cytotoxicity assays. this enhancement correlated strictly with an increased formation of nk cell or lak cell/tumor cell conjugate formation. information on the chemical specific ...19901692765
flow cytometric analyses of lectin binding to pneumocystis carinii surface carbohydrates.pneumocystis carinii obtained from infected rat lung homogenates was incubated with fluorescein isothiocyanate-conjugated lectins, counterstained with the nuclear stain, propidium iodide (pi), and analyzed by dual parameter histograms for lectin-associated green and pi-associated red fluorescence using a fluorescence-activated cell sorter. the presence of glucose/mannose moieties was evidenced by the binding of all organisms to concanavalin a and wisteria floribunda. from the lectin group specif ...19921556643
[predictability of the activity of drug combinations--yes or no (author's transl)].the following experiments were carried out on the question of the "predictability" of the effect of drug combinations. a methanol extract from viscum album causes a rise in coronary perfusion in isolated and perfused (langendorff's method) guinea pig hearts. administration of a methanol extract from crataegus oxyacantha results not only in a rise in coronary perfusion, but also in a positive inotropic effect. combined application of the drugs leads to a pure addition of effects, which are theref ...19751242658
inhibitory effect of korean mistletoe (viscum album coloratum) extract on tumour angiogenesis and metastasis of haematogenous and non-haematogenous tumour cells in mice.we examined the inhibitory effect of an aqueous extract (referred to as km-110) from viscum album coloratum, a korean mistletoe, on tumour metastasis produced by highly metastatic murine tumour cells, b16-bl6 melanoma, colon 26-m3.1 carcinoma and l5178y-ml25 lymphoma cells, using experimental and spontaneous metastasis models in syngeneic mice. in experimental metastasis of b16-bl6 and colon 26-m3.1 cells, intravenous (i.v.) administration of km-110 (100 micrograms/mouse) 1 day after tumour inoc ...19957585483
generation of h2o2 by human neutrophils and changes of cytosolic ca2+ and ph of rat thymocytes in response to galactoside-binding proteins (lectins or immunoglobulins).in contrast to plant agglutinins, biological activities of animal/human lectins are not well defined yet. testing a panel of seven mammalian carbohydrate-binding proteins we have found that the dimeric lectin from chicken liver (cl-16) was a stimulator of h2o2 release from human neutrophils as well as effector for induction of cytosolic ca2+ and ph increase in rat thymocytes. activity of this lectin was comparable to potent galactoside-specific plant lectins such as viscum album l. agglutinin. t ...19979217968
identity of the n-terminal sequences of the three a chains of mistletoe (viscum album l.) lectins: homology with ricin-like plant toxins and single-chain ribosome-inhibiting proteins.mistletoe lectin (ml) i increases the production of cytokines by mononuclear cells and has been proposed as a useful biological response modifier in the treatment of cancer. two other lectins, ml ii and ml iii, have been identified in mistletoe. we report that the n-terminal sequences of the three a chains of ml i, ml ii and ml iii are identical, and have interesting homology with the n-terminal sequences of the a chain of ricin-like toxins and of single-chain ribosome-inhibiting proteins. in ad ...19921450445
are matrix-immobilized neoglycoproteins, plant and human lectins and carbohydrate--binding antibodies from human serum mediators of adhesion in vitro for carcinoma and lymphosarcoma cells?mediation of cell adhesion by defined molecules can be studied by their immobilization onto a nitrocellulose matrix and incubation with cells. in order to infer the capacity of deliberately selected protein-carbohydrate interactions to establish sugar-inhibitable cell adhesion, a panel of immobilized neoglycoproteins was employed for the murine lymphosarcoma lines raw-117 with low (p) and high (h10) metastatic capacity, a human mammary carcinoma line (du4475) and three human colon carcinoma line ...19957733629
mechanism of stimulation of human natural killer cytotoxicity by arabinogalactan from larix occidentalis.cultures of human peripheral blood mononuclear cells (pbmc) as well as cultures of preseparated peripheral non-adherent cells (pnac) and monocytes showed enhancement of natural killer (nk) cytotoxicity against k562 tumor cells when pretreated with arabinogalactan from larix occidentalis for 48-72 h. lack of enhanced responses of pbmc (37% of donors) did not necessarily mean that pnac and monocyte cultures were also non-responsive to arabinogalactan treatment. moreover, pbmc, pnac and monocytes o ...19938439987
high-level expression of a viscotoxin in arabidopsis thaliana gives enhanced resistance against plasmodiophora brassicae.viscotoxins are a group of toxic thionins found in several mistletoe species. the constitutive camv-omega promoter was used to drive the expression of the viscotoxin a3 cdna from viscum album in transgenic arabidopsis thaliana c24. lines with high viscotoxin a3 levels in all parts of the plant were selected and tested for resistance against the clubroot pathogen plasmodiophora brassicae. the transgenic lines were more resistant to infection by this pathogen than the parental line.19989526499
expression of lectin, interleukin-2 and histopathologic blood group binding sites in prostate cancer and its correlation with integrated optical density and syntactic structure analysis.the binding of several biotinylated biologic probes was determined in sections of 20 surgical specimens of prostate cancer and of 21 biopsy specimens of hyperplastic prostate. whereas neither the immunomodulatory, galactoside-specific lectin from viscum album nor the human beta-galactoside-specific lectin (m(r) 14 kd) or its specific antibody discerned any remarkable differences, the lectin from urtica dioica (uda) and interleukin-2, the in vitro production of which is enhanced by this lectin, e ...19957542001
inhibition of protein synthesis by a toxic lectin from viscum album l. (mistletoe).1. the haemagglutinating and toxic lectin from viscum album l. (mistletoe) inhibits protein synthesis in a lysate of rabbit reticulocytes, with an id50 (concentration giving 50% inhibition) of 2.6 microgram/ml. this effect is enhanced (id50 0.21 microgram/ml) if the lectin is reduced with 2-mercaptoethanol. 2. the lectin inhibits protein synthesis also in bl8l cells in culture. inhibition occurs after a lag time of 3 h. the id50 is 7 ng/ml, and increases after reduction of the lectin. 3. this an ...19807470084
regulation of gelatinase b (mmp-9) in leukocytes by plant lectins.the stimulatory or inhibitory effects of plant lectins on the production of gelatinase a (mmp-2) and gelatinase b (mmp-9) by mononuclear white blood cells was investigated by substrate zymography. leukocyte cultures from 24-h old buffy coats were spontaneously activated and produced high levels of gelatinase b. using such cultures the suppressing activity of the datura stramonium, viscum album, bauhinia purpurea, triticum aestivum and maackia amurensis lectins on gelatinase b induction were demo ...19989607327
biologic properties of iscador: a viscum album preparation i. hyperplasia of the thymic cortex and accelerated regeneration of hematopoietic cells following x-irradiation.we demonstrated that a preparation of viscum album (iscador) has unusual effects on the immune system. in cd-1 mice, the mean weight of the thymus increased from 45 to 85 mg. following six daily intraperitoneal injections of 2.5 mg. of iscador. the thymic trophic influence was maintained over a long period of time. sprague-dawley rats treated with iscador for 16 weeks showed an increase of 78% in thymic weight over controls. the increased weight of the thymus was due to increased proliferation o ...19817453129
influence of the galactoside-specific lectin from viscum album and its subunits on cell aggregation and selected intracellular parameters of rat thymocytes.galactose-specific lectin from viscum album (vaa) was shown to induce the aggregation of rat thymocytes, to increase the intracellular ca(2+)-availability, and to enhance the menadione-dependent release of h2o2 from cells in a carbohydrate- and dose-dependent manner. this activity was mediated by the carbohydrate-binding b-subunit, whereas the toxic a-subunit failed to display aggregating activity or to affect the intracellular ca2+. however, incubation of cells in its presence decreased the rel ...19957753919
galactose-specific lectin from viscum album as a mediator of aggregation and priming of human platelets.galactose-specific lectin from viscum album (vaa) was found to induce aggregation of human platelets in a dose- and sugar-dependent manner. small nonaggregating concentrations of vaa primed the response of platelets to known aggregants (adp, arachidonic acid, thrombin, ristocetin, and a23187). vaa-induced platelet aggregation was completely reversible by addition of the sugar inhibitor lactose and the platelets from disrupted aggregates maintained the response to other aggregants. the lectin-ind ...19957763007
effects of the turkish subspecies of viscum album on macrophage-derived cytokines.viscum album l. herbs are used for the treatment of various diseases. apart from their immunostimulatory, antitumor, and hypotension inducing activities, anti-inflammatory effects has also been recorded in the literature. since the immunostimulatory activity of mistletoe is mainly attributed to a stimulation of the mononuclear phagocytic system and to an induction of inflammation by macrophage-derived cytokines, utilization based on anti-inflammatory activity seems in contrast with its use as im ...19989705010
study of an argentine mistletoe, the hemiparasite ligaria cuneifolia (r. et p.) tiegh. (loranthaceae).ligaria cuneifolia (r. et p.) tiegh. is an hemiparasite species used in argentine folk medicine as a substitute for the european mistletoe (viscum album l.) based on its putative activity of decreasing high blood pressure. this paper analyzes flavonoid composition, protein constituents and the possible immunomodulatory and antitumoral effects of this species. micromolecular study disclosed quercetin-free, quercetin-glycosylated and proanthocyanidins corresponding to cyanidin monomers, which impl ...19989720608
effects of mistletoe (viscum album l.) extracts on cultured tumor cells.bacterially fermented mistletoe preparations (bfmp) were tested on rat hepatoma tissue culture (htc) cells and human leukemia molt 4 cells. a dose-dependent inhibition of the growth rate of the cells was observed. for both cell lines, cytostatic concentrations, expressed in weight of fresh plant, were 0.5 mg/ml culture medium for oak bfmp and 1 mg/ml for apple tree bfmp. however, the action of the two preparations was markedly different on each cell line. non-viable htc cells were not stained by ...19863013672
stimulation of antitumour immunity by intrapleural instillation of a viscum album l. extract.intrapleural administration of mistletoe extracts is reported to result in pleurodesis in cancer patients with malignant pleural effusions. in a recent study, 20 consecutive cancer patients with malignant pleural effusions were treated intrapleurally with the mistletoe extract helixor. the overall response rate for pleurodesis was 72%, with only 1.2% displaying side effects of the world health organization classification i. the decline of tumour cells in the effusion liquid correlated negatively ...19979179363
viscum album l. preparation isorel modifies the immune response in normal and in tumour-bearing mice.the viscum album (mistletoe) preparation isorel is able to destroy tumour cells and to modify immune reactivity against a particular antigen in normal and in tumour-bearing animals. cba/hzgr mice and methylcholanthrene-induced fibrosarcoma were used in these studies. a single dose of isorel m (140 mg/kg or 1400 mg/kg body weight) significantly increased the number of plaque forming cells if applied at the time of injection of sheep red blood cells or 1 day earlier. the application of isorel 1 da ...19979179364
effect of a recombinant lectin, viscum album agglutinin on the secretion of interleukin-12 in cultured human peripheral blood mononuclear cells and on nk-cell-mediated cytotoxicity of rat splenocytes in vitro and in vivo.a plant lectin, viscum album agglutinin-i (vaa-i) has been shown to increase the number and cytotoxic activity of natural killer (nk) cells in animal models, but the mechanisms underlying these effects are poorly understood. we investigated the effects of the recombinant form of this lectin (rvaa) on secretion of interleukin (il)-12 and on nk-mediated cytotoxicity against k562 target cells in cultures of human peripheral blood mononuclear cells (pbmc) as well as against yac-1 target cells in cul ...19989789123
tumoricidal activity of mouse peritoneal macrophages treated with viscum album extract.macrophages from mice treated with viscum album extract were shown to be active in inhibiting the proliferation of tumour cells in culture. these activated macrophages have now been shown to protect mice from dying of progressive tumours when injected intraperitoneally into the animals. prophylactic as well as multiple treatments with macrophages activated with viscum album extract seemed more effective than a single treatment. the present finding suggests that in addition to a direct cytotoxic ...19938262566
immunomodulatory effects of viscum album agglutinin-i on natural 24 h cultured human peripheral blood mononuclear cells, treated with various (1 microgram/ml to 1 ng/ml) concentrations of viscum album agglutinin-i, quantitative assessment of dna breaks labelled with terminal deoxynucleotidyl transferase revealed a dose-dependent viscum album agglutinin-i-induced apoptosis above a lectin concentration of 10 ng/ml. after 24 h incubation of peripheral blood mononuclear cells with non-cytotoxic concentrations of viscum album agglutinin-i (10 and 1 ng/ml), mess ...19979179367
no-dependent regulation of lectin- and menadione-induced h2o2 production by cells from pleural effusions of lung cancer patients and by immune cells.molecular mechanisms of interplay between reactive oxygen (superoxide, hydroxyl radical, h2o2 etc.) and nitrogen (nitric oxide - no, onoo-, no2-, no3- etc.) forms are proposed to be of key importance for cell and tumor biology. considering no as a signal molecule we have studied the impact of no release on processes of generation of h2o2 in different experimental systems including pleural effusions (pe) of lung cancer patients, human polymorphonuclear leukocytes (pmns), and rat thymocytes. it wa ...199910087331
crystal structure of mistletoe lectin i from viscum album.the crystal structure of the ribosome-inactivating protein (rip) mistletoe lectin i (ml-i) from viscum album has been solved by molecular replacement techniques. the structure has been refined to a crystallographic r-factor of 24.5% using x-ray diffraction data to 2.8 a resolution. the heterodimeric 63-kda protein consists of a toxic a subunit which exhibits rna-glycosidase activity and a galactose-specific lectin b subunit. the overall protein fold is similar to that of ricin from ricinus commu ...199910198229
mistletoe therapy for human cancer: the role of the natural killer cells.extracts produced from viscum album l. (mistletoe) as well as certain isolated components are able to stimulate different functions of the immune system. the natural killer cells have been suggested as one of the candidates for direct tumour cell destruction. these cells are defined by their ability to mediate non-major histocompatibility complex (mhc) restricted cytotoxicity without prior sensitization against a specific antigen. however, their effectiveness in tumor defence in vivo is unclear. ...19979179368
donor-dependent and dose-dependent variation in the induction of t lymphocyte locomotion in a three-dimensional collagen matrix system by a mistletoe preparation (iscador).controlled activation of non-specific and specific immune defence mechanisms can beneficially manipulate the host's ability to attack malignant cells. in this context, migration and tissue distribution of immunocompetent cells may be prerequisites for an efficient immune surveillance. the effect of various non-cytotoxic concentrations of the viscum album l. (mistletoe) preparation iscadore qufrf on the locomotory activity of immunomagnetically isolated human cd4+ and cd8+ t lymphocytes from heal ...19979179371
apoptosis-inducing properties of viscum album l. extracts from different host trees, correlate with their content of toxic mistletoe lectins.extracts from viscum album l. (val), which are one of the most widely used alternative cancer therapies in europe, have been recognised to induce apoptosis. a clinically relevant direct anti-tumour effect might be induced only by their intratumoural or intrapleural injection, and thus effectiveness is highly dependent on the apoptosis-inducing potencies of the extracts used.199910226520
in u-937 promonocytes, misteltoe lectin i increases basal [ca2+]i, enhances histamine h1- and complement c5a-receptor-mediated rises in [ca2+]i, and induces cell death.mistletoe lectin i (ml i) from viscum album inhibits cell growth and induces apoptosis (programmed cell death) in several cell types. because increases in cytosolic ca2+ concentration ([ca2+]i) constitute a signal for the induction of apoptosis, we studied the effects of ml i on basal [ca2+]i, receptor-mediated rises in [ca2+]i and cell viability, using human u-937 promonocytes as model system. treatment of u-937 cells with ml i (30-100 ng/ml) significantly increased basal [ca2+]i. ml i (10-30 n ...19979050011
modulation of lectin-triggered superoxide release from neutrophils of tumor patients with and without chemotherapy.superoxide production by neutrophils is believed to contribute to the efficiency of the host defence system. this activity is stimulated by the mannose-specific lectin concanavalin a, the n-acetylglucosamine/neuraminic acid-specific wheat germ agglutinin and the galactoside-specific lectins from viscum album and human placenta. to assess whether this aspect of immune function is affected in cancer patients without or with treatment, neutrophil preparations from 69 patients were examined. reducti ...19938267383
efficient induction of superoxide release from human neutrophils by the galactoside-specific lectin from viscum album.the immunomodulatory galactoside-specific lectin from viscum album (vaa) induces superoxide anion (o2.-) release from human neutrophils. among twelve tested lectins, vaa, has the highest activity, clearly surpassing the effect of the human beta-galactoside-specific lectin (galaptin). its reactivity is blocked in the presence of lactose and is strictly dependent on the carbohydrate-binding b-subunit. the toxic a-subunit of the lectin does not elicit a response. the vaa-induced respiratory burst i ...19938392351
no evidence of ifn-gamma increase in the serum of hiv-positive and healthy subjects after subcutaneous injection of a non-fermented viscum album l. extract.iscador, an aqueous extract of viscum album l., has been used for more than 80 years as an anticancer drug. due to its immunomodulatory potential, since the onset of the aids epidemic it has also been applied in the treatment of hiv-positive and aids patients in the form of the preparation v. album qufrf (vaqufrf; labor hiscia, arlesheim, switzerland). in in vitro investigations, incubation of peripheral blood mononuclear cells with v. album l. extracts resulted in stimulation of lymphocyte acti ...199810366786
thionins from viscum album l: influence of the viscotoxins on the activation of granulocytes.extracts from european mistletoe (viscum album l.) are applied in adjuvant cancer treatment, and some components, especially the mistletoe lectins (ml) have been immunologically characterised, but not the thionins, termed viscotoxins (vt).199910368652
induction of mitochondrial apo2.7 molecules and generation of reactive oxygen-intermediates in cultured lymphocytes by the toxic proteins from viscum album l.we analysed mitochondrial alterations in human lymphocytes incubated with toxins exerting rna and/or protein synthesis/transport inhibitory activity. we found that all toxins known to affect macromolecule synthesis, such as ricin from ricinus communis, mistletoe lectin i (ml i) from viscum album, cycloheximide, actinomycin d, and brefeldin a but also the thionins from viscum album (viscotoxins; vt) generated reactive oxygen intermediates (roi) and induced expression of newly described mitochondr ...199910408913
ligands for viscum album agglutinin and galectin-1 in human lung cancer: is there any prognostic relevance?viscum album agglutinin (vaa) is an extract component of mistletoe. it belongs to the plant lectin family and exerts various biological effects such as cytotoxic properties for tumor cells in culture. vaa as well as galectin-1, an endogenous lectin, possess galactose-specific surface-binding sites. we therefore investigated 159 cases of lung cancer for their capacity to bind vaa and galectin-1 and for lewis antigen reactivity. three different methods were used for detection of vaa: a two-step me ...199910443287
differences in the apoptosis-inducing properties of viscum album l. extracts.viscum album l. (mistletoe) extracts are widely used in adjuvant cancer therapy. in contrast to purified components, such as mistletoe lectins and viscotoxins, whole plant extracts of mistletoe resulted in dna stabilizations in cyclophosphamide-treated lymphocytes but also provided cytotoxicity in tumour cells and lymphocytes. the killing capacities of mistletoe extracts were host tree-specific and not correlated with mistletoe lectin or viscotoxin content. in human lymphocytes, only mistletoe l ...19979179360
[mistletoe therapy from the pharmacologic perspective].because of their cytostatic/apoptotic and immunomodulatory effects mistletoe extracts are often applied in tumour patients. recent experimental data suggest that the mistletoe lectins viscum album agglutinin (vaa)-i and -ii are play an important role in the efficacy of mistletoe therapy. vaa-i and -ii are members of the type-ii ribosome-inactivating proteins. vaa-i has been shown to induce cytostatic effects in cultures of various eukaryotic cells in vitro. in 24-hour cultures of human periphera ...199910529578
tolerability of an extract of european mistletoe among immunocompromised and healthy individuals.european mistletoe (viscum album l) has been used parenterally for more than 80 years as an anticancer medication with significant immunomodulating action. since 1984, clinical experience with a viscum album extract (viscum album quercus frischsaft [qu frf]) among hiv-positive patients has suggested that it inhibits hiv disease progression.199910550904
selective modulation of phosphatidylserine exposure on subpopulations of human peripheral blood lymphocytes by a plant lectin, viscum album agglutinin (vaa)-i and its recombinant form (rvaa) in vitro.growing evidence suggests that lectin-carbohydrate interactions are involved in the regulation of the balance between cell growth and programmed cell death. viscum album agglutinin (vaa)-i is a galactoside-specific, type ii ribosome-inactivating plant lectin. at concentrations less than 10 ng/ml, vaa-i has been shown to induce gene expression and secretion of proinflammatory cytokines as well as apoptosis in cultures of human peripheral blood mononuclear cells (pbmc). this study analyzes the eff ...199910571662
microcalorimetric indications for ligand binding as a function of the protein for galactoside-specific plant and avian lectins.the process cascade leading to the final accommodation of the carbohydrate ligand in the lectin's binding site comprises enthalpic and entropic contributions of the binding partners and solvent molecules. with emphasis on lactose, n-acetyllactosamine, and thiodigalactoside as potent inhibitors of binding of galactoside-specific lectins, the question was addressed to what extent these parameters are affected as a function of the protein. the microcalorimetric study of carbohydrate association to ...199910572940
effects of mistletoe lectin i and ionizing radiation on the glucose and thymidine uptake in tumour cells in vitro.the increased uptake of hexose by mammalian cells is considered to be a general response to stress. nowadays, mistletoe lectin separated from the extracts of the european mistletoe (viscum album l.) is often used in adjuvant cancer therapy. the present work studies the effect of the lectin on unirradiated and x-irradiated tumour cells. the response of cultured human lung carcinoma cells (calu-1) was followed by radioactive glucose uptake as well as by tritiated thymidine incorporation. the cells ...199910594933
influence of polysaccharides from viscum album l. on human lymphocytes, monocytes and granulocytes in acidic arabinogalactan from european mistletoe (viscum album l, val; 1.34 x 10(6) dalton) was studied in detail because its immunological properties are poorly characterised.199910628330
viscotoxin-free aqueous extracts from european mistletoe (viscum album l.) stimulate activity of human granulocytes.extracts from european mistletoe (viscum album l., val) are used for complementary cancer treatment. viscotoxins (vt) and whole plant extracts with high amounts of the vt have been shown to stimulate functional activity of granulocytes.199910652574
lack of an antitumoral effect of immunomodulatory galactoside-specific mistletoe lectin on n-methyl-n-nitrosourea-induced urinary bladder carcinogenesis in rats.the aim of the present animal experiment was to study the effect of galactoside-specific lectin or agglutinin (vaa) from mistletoe (viscum album l.) on chemically induced tumor development in the urinary bladder of rats. since vaa has been shown to exert a remarkable immunomodulating effect, any change in tumor formation would indicate a lectin-triggered immune control of urothelial carcinogenesis in the used model. to produce vesical neoplasms the direct-acting urothelial carcinogen n-methyl-n- ...19979314050
fine sugar specificity of the mistletoe (viscum album) lectin i.the behaviour of n-acetyllactosamine-type oligosaccharides and glycopeptides on a column of mistletoe lectin i (mli) immobilized on sepharose 4b was examined. the immobilized lectin does not show any affinity for asialo-n-glycosylpeptides and related oligosaccharides, which possess one to four unmasked n-acetyllactosamine sequences. however, substitution of at least one of the n-acetyllactosamine sequences by sialic acid residues, either at o-3 or o-6 of galactose, slightly enhances the affinity ...19947696858
cytotoxicity of heat-treated korean mistletoe.the cytotoxic effects of preparations of korean mistletoe (viscum album l. var. coloratum ohwi) on non-tumorigenic a31 cells and tumorigenic msv cells were investigated. while the aqueous extract from korean mistletoe (<8 microg/ml) showed strong cytotoxicity on both cell lines, the heat-treated extract was much less cytotoxic with td50 values of above 300 microg/ml. the heat-treated extract showed a growth-enhancing effect on non-tumorigenic cells and a cytotoxic effect on tumorigenic cells. th ...19989563647
[study of plant lectins from viscum album using monoclonal antibodies].monoclonal antibodies (monat) against both native (ta5, tb12) and denatured (tb33, tb35) plant toxin ml1 from viscum album have been obtained. the interaction of monat against native toxin with its isoforms ml2 and ml3 was investigated. it was shown that monat ta5 to a-chain of ml1 toxin cross-reacted with ml2 and ml3 isoforms. ta5 did not inhibit enzyme activity of a-chain in cell-free rabbit reticulocyte system. it was shown that monat tb12 reacted with galactose-binding site of b-subunit. bot ...19958552066
a natural immunity-activating plant lectin, viscum album agglutinin-i, induces apoptosis in human lymphocytes, monocytes, monocytic thp-1 cells and murine thymocytes.a galactoside-specific plant lectin, viscum album agglutinin-i (vaa-i) with protein synthesis-inhibiting properties, has been shown to be cytotoxic in various eukaryotic cells, in vitro above a 10 ng/ml concentration. noncytotoxic concentrations of vaa-i induced mrna expression and enhanced secretion of proinflammatory cytokines in cultures of human peripheral blood mononuclear cells. in an animal model vaa-i has been shown to stimulate natural killer cells and granulocytes. in this study, human ...19969523281
induction of apoptosis in human lymphocytes treated with viscum album l. is mediated by the mistletoe lectins.viscum album l. (val) is a phytopreparation used in adjuvant cancer therapy with both immunostimulatory and dna stabilizing properties at low drug concentrations and cytostatic/cytotoxic properties at higher concentrations. the present work examines the cytotoxic effects of val extracts produced from mistletoes grown on different host trees and of purified toxic proteins from val, such as the d-galactose-specific lectin i (ml i), the n-acetyl-d-galactosamine-specific ml ii and ml iii, and crude ...19968564930
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