32 results about "Lethal toxin" patented technology

Current chemotherapeutic approaches for cancer are in part limited by the inability of drugs to destroy neoplastic cells within poorly vascularized compartments of tumors. We have here systematically assessed anaerobic bacteria for their capacity to grow expansively within avascutar compartments of transplanted tumors. Among 26 different strains tested, one (Clostridium novyi) appeared particularly promising. We created a strain of C. novyi devoid of its lethal toxin (C. novyi-NT) and showed that intravenously injected C. novyi-NT spores germinated within the avascular regions of tumors in mice and destroyed surrounding viable tumor cells. When C. novyi-NT spores were administered together with conventional chemotherapeutic drugs, extensive hemorrhagic necrosis of tumors often developed within 24 hours, resulting in significant and prolonged anti-tumor effects. This strategy, called combination bacteriolytic therapy (COBALT), has the potential to add a valuablle dimension to the treatment of cancer.

The invention relates to a method for a tetanus toxin receptor binding domain Hc to be subjected to high-level soluble expression in Escherichia coli through nucleotide sequence optimization. According to the sequencing result of a domestic C.Tetani virulent strain CMCC64008, the tetanus toxin receptor binding domain Hc sequence is analyzed and optimized, the optimized sequence is SEQ ID No.1 and the coded protein sequence is SEQ ID No.2. The synthesized Hc gene is linked into an expression vector pET32a(+) after undergoing double enzyme digestion, the recombinant Hc is subjected to high soluble expression in Escherichia coli and the target protein accounts for about 46% of the total protein in the supernatant undergoing bacteriociasis. After QFF column purification, phenyl hydrophobic column purification and SP column purification, the purity of the target protein can be more than 95% and the yield thereof is more than 300mg / L. The recombinant protein prepared by the method of the invention has good immunogenicity, can induce the mice to produce high-titre protective antibodies and can resist attack of high-dose lethal toxins. The method has extensive application prospect in large-scale high-level preparation of the tetanus toxin recombinant subunit vaccine Hc.

The present invention provides methods for inhibiting tumor associated angiogenesis by administering a mutant protective antigen protein comprising a matrix metalloproteinase-recognized cleavage site in place of the native protective antigen furin-recognized site in combination with a lethal factor polypeptide comprising a protective antigen binding site. Upon cleavage of the mutant protective antigen by a matrix metalloproteinase, the lethal factor polypeptide is translocated into cancer and endothelial cells and inhibits tumor associated angiogenesis.

The invention provides an analysis method for lethal toxicity of environmental pollutants to caenorhabditis eleganses. The analysis method comprises the following steps: diluting synchronized caenorhabditis elegans culture solutions to obtain a caenorhabditis elegans sample solution; diluting an environmental-pollutant stock solution into n environmental-pollutant sample solutions according to a geometric concentration gradient; adding the caenorhabditis elegans sample solution into transparent micropores, correspondingly adding the environmental-pollutant sample solutions with different concentrations, adopting the transparent micropores without adding the environmental-pollutant sample solution as a blank control, and after culture for t0 hours, acquiring the number of normalized survival caenorhabditis eleganses and calculating normalized lethallty rate; and calculating median lethal concentration of the environmental pollutants by curve fitting. According to the analysis method provided by the invention, the lethal toxicity of the environmental pollutants to the caenorhabditis eleganses can be accurately calculated out, more statistic significance is achieved, and more scientific theoretical support can be provided for evaluating the safety problem of the environmental pollutants to the ecological system and the human health.

The invention provides low molecular weight compounds that block the pore formed by protective antigen and inhibit anthrax toxin action. Structures of the compounds are derivatives of β-cyclodextrin. Per-substituted alkylamino derivatives displayed inhibitory activity, and they were protective against anthrax lethal toxin action at low micromolar concentrations. Also, the addition of one of the alkylamino derivatives to the bilayer lipid membrane with multiple PA channels caused a significant decrease in membrane conductance. Thus, the invention also provides methods for protection against anthrax toxicity.

The present invention provides a use of soluble P-selectin in treating systemic hemorrhagic conditions, stabilizing blood pressure, and protecting hypoxic / ischemic tissues. Also provided is a use of anthrax lethal toxin in treating thrombotic conditions.

A phospholipase A2 inhibitor protein designated “Phospholipase Inhibitor from Python” (PIP)—formerly designated “Python Antitoxic Factor” (PAF)—is given by SEQ ID NO:2. The partial amino acid sequence for PIP was initially determined from the native protein purified from the blood serum of a non-venomous snake, Python reticulatus. The complete PIP polynucleotide sequence was obtained from a cDNA clone encoding PIP, given by SEQ ID NO:1, along with the full amino acid sequence deduced from it. Also disclosed is a recombinant protein PIP, which shows strong lethal toxin neutralizing activity similar to the native PIP, and has potent anti-inflammatory activity. Both the native and the functionally equivalent recombinant PIP are useful for the prevention or treatment of conditions such as snakebites, insect stings, and inflammatory diseases. Also, phospholipase A2 (PLA2) inhibitory polypeptides designated P-0029, P-0009, and P-0006, the sequences of which are given as SEQ ID NO:10, SEQ ID NO:11, and SEQ ID NO:12, respectively, are disclosed. Those polypeptides, and their synthetic chemical analogues and polypeptide variants that inhibit PLA2 activity and alleviate inflammation, may also be used in the diagnosis, study, prevention, and treatment of PLA2-related human inflammatory diseases.

One major problem in diagnosis methods presently available for anthrax is that these methods require several days to produce a result. The only existing treatment for anthrax requires administration soon after infection at a time when patients are exhibiting only mild flu-like symptoms. Thus, a patient may be days beyond the time when treatment would be effective by the time a diagnosis is made. The present invention reduces diagnosis time to as little as four hours providing same day identification of anthrax radically increasing the odds of delivering proper treatment and patient recovery. The rapid identification of anthrax lethal factor activity exhibited by the instant invention is also amenable to in vivo screening protocols for the discovery and development of anthrax vaccines and lethal factor inhibitors. The instant invention isolates and concentrates lethal factor and lethal toxin from nearly any biological sample. By capitalizing on the endopeptidase activity of lethal factor the present invention amplifies output signals producing reliable detection of picomolar concentrations of lethal factor. The instant invention involves novel purification and detection techniques and substrates for rapid, reproducible, and quantitative measurements of anthrax lethal factor in biological samples.

Regions of B. anthracis protective antigen are provided representing sequences recognized by antibodies in subjects that have vaccine induced lethal toxin neutralizing anti-PA IgG responses. The recognition of these PA regions enhances the utility of anti-PA IgG reactivity as an immune correlate of protection against anthrax in a subject and increases predictive probability of survival. Also provided are vaccines that include at least one of these PA regions that when administered to a subject improve the predictive value of vaccine induced anti-PA IgG and TNA responses as immune correlates of protection against inhalation anthrax.

The present invention provides a use of soluble P-selectin in treating systemic hemorrhagic conditions, stabilizing blood pressure, and protecting hypoxic / ischemic tissues. Also provided is a use of anthrax lethal toxin in treating thrombotic conditions.

The invention relates to the technical fields of animal bacteriology and zoonosis science, particularly to an application of a dominant inhibitory mutant F427D as an inhibitor of Bacillus anthracis toxin and an application of vaccine thereof. The invention, through cloning of Bacillus anthracis lethal toxin gene, expression and purification of proteins, site-directed saturation mutagenesis of genes and the like, obtains protective antigen (namely the dominant inhibitory mutant F427D) of the Bacillus anthracis, the mutant is successfully cloned into pronucleus expression carrier pGEX-KG and composes recomposed plasmid pGEX-KG-PA (F427D). Escherichia coli containing the recomposed plasmid is nominated as Escherichia coli DH5Alpha / pGEX-KG-PA (F427D) and collected in the China Center for TypeCulture Collection with a collection number of CCTCC-M208158. The invention further discloses the method for preparing the antigen protein, the preparation of anthrax toxin inhibitor and subunit vaccine by using the antigen protein and the application thereof.

The present invention identifies compounds that disrupt the interaction between anthrax proteins and LRP5 / 6 receptors, resulting in a reduction in anthrax toxicity. The compounds act to disrupt the intracellular transport of toxin complexes into a target cell. The present invention also provides methods for testing the effect of compounds on Wnt activity, through the use of in vitro experiments involving cells that have in at least one gene mutation involved in the Wnt pathway.

The invention provides a genetic engineering bivalent (rPA+rLF) anthrax vaccine.Active ingredients of the bivalent anthrax vaccine include R178A / K197A mutant protein rPA of anthrax protective antigen and R491A / L514A mutant protein rLF of a lethal factor.The vaccine is prepared from the protective antigen PA and lethal factor LF dominant biological inactivation mutant protein, the advantages are that the protective antigen PA and lethal factor LF cannot be combined, capacity of generating anthrax toxin of a natural composition and action of lethal toxicity are lost, the immunogenicity and protectiveness of the dominant biological inactivation mutant protein rPA are superior to wild protective antigen PA, and the dominant biological inactivation mutant protein rLF can stimulate an organism to increase the immune protective effect; therefore, by means of the bivalent genetic engineering vaccine, the protection effect of the mutant protein rPA is greatly enhanced, five times or more of lethal dose of the lethal toxin can be resisted to, meanwhile the biologically inactivated rPA and rLF can further compete for combining with a receptor to inhibit activity of wild toxin, the purpose of neutralizing anthrax toxin is achieved, and it is inspected to achieve a good protection effect on inhaled infection anthrax.

The invention relates to the technical field of marine organisms, in particular to a method for separating and purifying a cyanea nozakii lethal toxin protein. The method comprises the following steps of: ultrasonically crushing cyanea nozakii nematocyst cells to extract a jellyfish crude toxin, dialyzing and desalting, and separating and purifying by affinity chromatographic separation and an anion exchange chromatographic technology in turn to obtain a jellyfish toxin protein with lethal activity, wherein through measurement, the molecular weight of the toxin protein is 30kDa, and the lethal dose 50 (LD50) of the toxin protein to 1g of zebra fish is 0.56mu g. The method has the characteristics that: the method is quick, simple and convenient and provides important guidance for obtainingthe cyanea nozakii lethal toxin protein.

The invention relates to the use of soluble P-lectine in preparing medicament for treating whole body haemorrhage diseases, and the use of an anthracnose lethiferous toxin in preparing medicament for treating antithrombotic diseases.

The present invention belongs to the technical field of microorganism genetic engineering and particularly relates to a Bacillus anthracis protective antigen mutant and encoding protein thereof. The sequence of the mutant gene and the amino acid sequence of the encoding mutant protein are shown in SEQ ID NO: 1 in the sequence table. Through the verification of biology, the mutant protein has complete privation of cytotoxicity, and can inhibit the cytotoxicity of wild lethal toxin.