study on the effects of heat treatment on the detection and toxicity of ricin added to milk- and soy-based infant formulas. Half-lives of ricin cytotoxicactivity in a milk-based infant formula at 70°C, 75°C, 80°C, 85°C, and 90°C are 9.8, 5.8, 5.1, 3.1, and 1.8 min, respectively, the comparable values for a soy-based infant formula are 16, 8.7, 6.9, 3.0, and 2.0 min
enables easy immunotoxin creation by coupling target antigen to artificial cysteine residue at non-enzyme-interfering C-terminus of toxin in a predictive way
transgenic tobacco plants transfected with the enzyme from barley acquire an increased resistance to Rhizoctonia solani infection. The expression of barley gene in transgenic mulberry displays enhanced tolerance against drought, salinity and cold stress
detection method based on N-glycosidase activity of ricin. Ricin is captured by a monoclonal antibody directed against the B chain and immobilized. Detection is realized via the release of adenine by the ricin A chain. Limit of detection is around 0.1 ng/ml after concentration of the toxin
detection method for ricin based on its inhibitory effects on protein synthesis. Development of an array of protein expression units to accomodate controls and multiple samples. Detection limit is around 0.01 nM ricin
evaluation of rapid measurement platform using fluorogenic hand-held immunoassays for ricin A chain. Detection limit is 14 ng/ml or 140 pg/test. The assays are inclusive for ricin A60, ricin A120, ricin A chain, and ricin B chain and exclusive in discrimination of ricin A60 from other toxins
highly selective and sensitive aptamer-based abrin assay using a molecular light switching reagent [Ru(phen)2(dppz)]2+ with a limit of detection of 1 nM and a wide linear range from 1 to 400 nM with the correlation coefficient of 0.993. Assay can be performed in physiological buffers as well as diluted serum
identification of single domain antibodies bound to ricin immobilized on the surface of microspheres. Use as effective capture molecules in sandwich immunoassays
isolation of aptamers that specifically recognize ricin by affinity chromatography and by capillary electrophoresis/systematic evolution of ligands by exponential enrichment, i.e. CE-SELEX. Identification of three aptamers with Kd values in the nanomolar range that do not recognize abrin toxin
rapid and selective detection of ricin using fluorescently tagged RNA aptamers. Dissociation constant is 134 nM for RNA aptamer and ricin A chain, detection limit for ricin is around 1 nM
sensitive immuno-polymerase chain reaction assay for detection of ribosome-inactivating proteins, limit of detection is about 10 fg/ml of dianthin or ricin, and the test can be applied to human serum
sensitive immuno-polymerase chain reaction assay for detection of ribosome-inactivating proteins, limit of detection is about 10 fg/ml of dianthin or ricin, and the test can be applied to human serum
validation of a cell-free translation assay for determining ricin biological activity. Assay is specific for determining ricin in food-based matrixes and discriminates ricin from other ribosome-inactivating proteins
facile analysis of RIP catalytic activity will have applications in plant toxin detection, inhibitor screens, mechanistic analysis of depurinating agents on oligonucleotides and intact ribosomes, and in cancer immunochemotherapy
simple and cost effective N-glycosidase assay based on the direct determination of the released adenine by thin-layer chromatography and TLC-densitometry. An adenine based single stranded oligonucleotide is used as substrate. The released adenine is quantified on silica glass plates by UV absorbance at 260 nm
simple and cost effective N-glycosidase assay based on the direct determination of the released adenine by thin-layer chromatography and TLC-densitometry. An adenine based single stranded oligonucleotide is used as substrate. The released adenine is quantified on silica glass plates by UV absorbance at 260 nm
combined expression of a barley class II chitinase and type I ribosome inactivating protein in transgenic Brassica juncea provides protection against Alternaria brassicae
ricin is a prototype for the construction of chimeric molecules, called immunotoxins, based on the structure of the A-B toxins. An application of the ricin B as a carrier is the fusion and expression with different viral antigens used for vaccination therapies. A fusion protein combining the genes for endotoxin of Bacillus thuringiensis with the ricin B chain, and transgenic rice and maize plants expressing the fusion protein are more toxic to insects than plants containing the toxin gene alone
saporin conjugated to oxytocin is an effective neurotoxin for in vivo elimination of cells that express oxytocin receptors and is potentially useful to analyze central nervous system mechanisms that involve the action of oxytocin on food intake and other physiological processes
saporin is fused to ubiquitin to allow a rapid degradation of the toxin via the ubiquitin-proteasome system in non-target cells. Saporin is the preferred toxin for constructing anti-neuronal immunotoxins and neuropeptide-toxin conjugates. The saporin gene is also used as a tool for suicide gene therapy
differentiation of castor bean toxins from other N-glycosidase toxins depending on the signal to background ratio of the substrate GdAAA to GdAGA, castor bean extract can be distinguished from jequirity seed extract (Abrus precatorius)
differentiation of castor bean toxins from other N-glycosidase toxins depending on the signal to background ratio of the substrate GdAAA to GdAGA, castor bean extract can be distinguished from jequirity seed extract, ricin equivalent activity for jequirity seed 200-fold higher than with immunoassay
identification of highly toxic Escherichia coli variants in humans, animals, and food by using primer homologous to the elastase recognition site of Stx2dact or other variants
identification of substrate and product of ricin toxin A-chain with 3 different DNA stem-loop probes with fluorophore and quencher linked to the 5'- and 3'-ends or vice versa hybridized to substrate or ricin, respectively, lower limit of detection 14 ng/ml of ricin toxin chain a
identification of toxin with Vero-2dEGFP assay, threshold for toxin detection 10 picog/ml, and identification of toxin inhibitors, 10% glycerol enhances fluorescence signal
ricin identification in food (milk, apple juice) or clinical samples (serum, saliva) with DNA substrate that mimics the natural RNA target combined with MALDI-TOF analysis of DNA to identify depurination (1-5 pmol ricin detectable), and tryptic digestion of ricin and analysis with LC-MS/MS
RIP proteins display a variety of activities in addition to rRNA N-glycosidase activity, antiviral, antifungal, apoptosis-inducing, antitumor, immunosuppressive, and HIV-1 integrase inhibitory activity, because of their translational inhibitory activity and other pharmacological properties, they have been regarded as having great potential for use as selective cell-killing agents
trichoanguin examined for preparation of immunotoxins, with a great potential for application as an effective chemotherapeutic agent for the treatment of various cancers or AIDS
DNA damaging activity of gelonin may be responsible for the elimination of the parasite 6 Kb extrachromosomal mitochondrial DNA of Plasmodium falciparum infected erythrocytes
trichosanthin is immunogenic and leads to IgE production in humans, Trichosanthes kirilowii is a traditional chinese medicine plant, root tubers containing trichosanthin cause abortion, overview
construct of recombinant gelonin fused to cytokine B lymphocyte stimulator to specifically target quiescent B-CLL lymphocytes. The construct specifically binds and internalizes through cell-surface receptor BAFF-R into CD19 B-CLL lymphocytes and induces apoptosis at nanomolar concentrations. In contrast, rGel alone is not able to internalize into these leukemic lymphocytes. Mechanistically, the construct inhibits protein synthesis with an IC50 of less than 3 nM compared with more than 5000 nM for rGel toxin alone
construction of a chimeric antibody using variable region genes of anti-ricin monoclonal antibody 4C13 which can neutralize the toxicitiy of ricin, and human constant region genes. The chimeric antibody blocks ricin-induced cytotoxicity to SP2/0 cells
construction of a immunotoxin consisting of the non-toxic type 2 ribosome-inactivating protein nigrin b linked to the monoclonal anti-human CD105 antibody 44G4. The immunotoxin kills specifically mouse fibroblasts expressing the biomarker CD105 with an IC50 value of 0.6 nM while nigrin does it at 0.24 microM. The immunotoxin accumulates in a perinuclear region
construction of chimeric toxin composed of saporin, a cleavable adapter, and human epidermic growth factor. Presence of the saponins saponinum album or quillajasaponin enhances cytotoxicity of the construct more than 1000fold and decreases IC50 values from 2.4 nM in absence of saponin to 0.18 pM in presence of saponinum album. Quillajasaponin enhances the cytotoxicity both on control cells lacking epidermal growth factor receptor and on target cells, while saponinum album is target cell receptor specific
coupling of an anti-CD38 monoclonal antibody to saporin-S6 and treatment of selected human CD38+ cell ines and CD38+ neoplastic cells from a NonHodgkin Lymphoma patient. In HBL6, Raji and L540 cells protein synthesis is completely inhibited by the conjugate at 100 pM. CD38+ cells from the patient wee completely eliminated after treatment at 10 nM while CFU-c rescue by bone marrow precursors was maintained
cubic morphology lyotropic mesophases containing galactose amphiphiles exhibit high specificity ricin uptake with high dissociation constants and high capactities, and may be used as ricin antitoxins
development of an oropharyngeal aspiration model for ricin lethal challenge and antibody administration. When polyclonal anti-deglycosylated ricin A chain antibody is administered between 1-18 h after ricin challenge, all mice survive, while delayed treatment to 24 h results in 30% survival. Protective effects of antibody correlate with inhibition of apoptosis in lungs in vivo and in RAW264.7 macrophage and Jurkat cells in vitro
disruption of vascular leak syndrome-inducing site and of ribotoxic site. Injection i.m. into mice protects them against a ricin challenge of 10 LD50s. Injection into humans shows that the mutant is safe and elicits ricin-neutralizing antibodies in five of five individuals in the high-dose group
evaluation of cytotoxicity of ricin A chain and ricin A chain fusion protein with enhanced green fluorescent protein in HeLa and HEP-G2 cells following fluid-phase endocytosis. Fusion protein ahs a similar toxicity like ricin A chain. After endocytosis, ricin A chain reaches the endoplasmic reticulum
expression of A chain in Escherichia coli with His-tag and purification. Construction of replication-deficient ricin B chain adenovirus-green fluorescent protein fusion protein. When used individually, neither A chain nor B chain protein is toxic to human cell lines HEK 293, HeLa, SMMC 7721, and HL 7702, and entry of A chain into cells infected with the fusion contruct is confirmed. When applied together, significant cell death is observed in all cell lines tested
following encapsulation in negatively charged liposomes, the cytotoxicity of ricin in chinese hamster ovary cells is markedly reduced. Lactose has no effect on the binding, internalization, and cytotoxicity of liposomal ricin. Both monensin and NH4Cl markedly enhance the cytotoxicity of liposomal ricin. The extent of exocytosis of free ricin is much higher as compared to liposomal ricin
fusion of the CTL epitope from the pneumonia virus of mice phosphoprotein to the mature 5'-terminus of the ricin A chain of the non-toxic mutant RTA6K-R180H. Fusion protein elicits a CD8+ T-cell response in mice directed against pneumonia virus of mice, and the T-cell response resulting from inoculation with the ricin-peptide fusion molecule delays the onset of virus-induced disease
in HeLa cells, ricin transport to the trans-Golgi network is inhibited when the small GTPase Rab6A messenger RNA levels are reduced by more than 40% and less than 75%. However, when Rab6A mRNA is reduced by more than 75% and Rab6AmRNA is simultaneously up-regulated, the inhibition of ricin sulfation is abolished. The depletion of both Rab6A and Rab6A gives a stronger inhibition of ricin sulfation than what is observed knocking down the two isoforms separately
injection of trichosanthin into rat eyes causes distinct retinal changes at 1 nM. Toxic effects are most pronounced in the cells of the outer nuclear layer, less pronounced on those of the inner nuclear layer, and little on the ganglion cells. Apoptosis is the predominant type of cell death induced by trichosanthin
isolation of monoclonal IgA antibodies active against ricin A chain or ricin B chain, respectively, that neutralize ricin in a Vero cell cytotoxicity assay, block toxin-induced interleukin-8 release by the human macrophage cell line 28SC, and protect polarized epithelial cell monolayers from ricin-mediated protein synthesis inhibition
major histocompatibility complex class I tetramers H2-Db assembled using streptavidin conjugated to the ribosome-inactivating protein saporin. These tetramers inhibit ribosome activity in vitro, retain the T-cell receptor-binding specificity of their nontoxic counterparts, and are internalized by 100% of target cells, leading to cell death in 72 hours. Cytotoxicity is dependent on the tetramer dose and avidity for the T cell
mice co-inoculated with purified recombinant ricin b chain plus 90-amino acid peptide from the simian rotavirus SA-11 nonstructural protein, NSP4 or heat denatured NSP490/ricin B chain fusion protein generate higher titers of serum anti-NSP490 IgG antibodies than mice immunized with NSP490 peptide alone, immunostimulatory function of ricin B chain
ricin interacts with the ER degradation enhancing alpha-mannosidase I-like protein EDEM responsible for redirecting aberrant proteins for ER-associated protein degradation and with Sec61alpha, and both kifunensin and puromycin enhance these interactions. Overexpression of EDEM strongly protects against ricin. In presence of kifunensin, EDEM promotes retranslocation of ricin from the ER to the cytosol
ricin stimulates human monocyte/macrophage cell line 28SC to secrete interleukin IL-8. IL-8 induction can be blocked by brefeldin A. After ricin exposure, p38 mitogen activated protein kinase levels are elevated. Treatment of cells with p38 mitogen activated protein kinase inhibitor SB203580 suppresses ricin-mediated IL-8 release
ricin toxicosis in a 12-week-old Mastiff puppy results in acute vomitting, diarrhea, and lethargy and subsequent death after several hours. Histopathologic findings include superficial necrotizing enteritis of the jejunum and occasional, random foci of coagulative necrosis in the liver
study on ricin A chain vaccine RTA 1-33/44-198 developed by protein engineering. Adsorption of the vaccine to aluminium hydroxide produces a small change in secondary structure that significantly stabilizes the protein to thermal denaturation
study on the cytotoxicity of ricin encapsulated in various liposomes. Cytotoxicity against CHO pro- cells is significnatly dependent on the charge on the surface of liposomes. Maximum cytotoxicity is observed by delivering ricin through negatively charged liposomes. Monensin enhances the cytotoxicity with maximum potentiation on delivery through positively charged liposomes and depending on the density of distearylphosphatidylethanolamine-mPEG-2000 on their surface
study on the endosome to Golgi transport of ricin in cell line LY-B deficient in serine palmitoyltransferase and in wildtype CHO-K1 cells in presence/absence of the inhibitor of sphingolipid biosynthesis, myriocin. Depletion of sphingolipids results in increased sensitivity to ricin. Endosome to Golgi transport of ricin is increased in sphingolipid-deficient cells. Additionally, cholesterol depletion inhibits endosome to Golgi transport even in cells with reduced levels of sphingolipids
treatment with dimethylsulfoxide and lipopolyamine administration both generate substantial cellular sensitization to ricin and a chemical conjugate of urokinase plasminogen activator and saporin used as anticancer toxin. Major site for the dimethylsulfoxide-facilitated entry of saporin into the cytosol is an endosomal trafficking step preceeding cargo delivery to the late endosome. Senitization effects are specific for saporin and suggest a translocation of saporin via endosomal disruption
C-terminal enzymatically active ricin A chain variants are specifically cleaved by HIV-1 protease both in vitro and in HIV-infected cells and the products mediate specific inhibitory effect towards HIV replication. Upon proteolysis, the processed variants show enhanced antiviral effect with low cytotoxicity towards uninfected cells