31 results about "Lipid A" patented technology

The invention discloses a salmonella typhimurium EN-VNP strain based on flagellin and LPS attenuation as well as a preparation method and application of the salmonella typhimurium EN-VNP strain, and particularly relates to the technical field of biology. The bacterial strain is formed by sequentially knocking out or silencing flagellin genes fliC and fljB, a phosphoethanolamine transferase gene eptA, a 4-amino-4-deoxy-L-arabinose transferase gene arnT and phosphotransferase yeiU on the basis of a salmonella VNP 20009 bacterial strain, and knocking in or overexpressing a phosphotransferase gene lpxE. The salmonella typhimurium EN-VNP strain disclosed by the invention has relatively high safety, the attenuated strain does not contain flagellin, and a lipid A molecule of LPS only retains one phosphate group, so that the safety of the strain is improved, and the strain is more suitable for serving as a vaccine and a drug delivery carrier.

The present invention discloses a recombinant Escherichia coli capable of efficiently producing monophospholipid A vaccine adjuvant, belonging to the fields of genetic engineering and synthetic biology. The present invention knocks out 132 genes related to membrane wall surface molecules, phospholipid and glucose transport, phosphoethanolamine modification and enoyl-ACP reductase in Escherichia coli MG1655, expresses lipid A modification genes FnlpxE, SepagP and SepagL, and constructs strain MW021 / pTEPL. The growth performance of MW021 / pTEPL is greatly improved and antibiotics and inducers are no longer required during the fermentation process; in a 2-L fermentation tank system, the highest OD of MW021 / pTEPL growth is 600 It can reach 38.54, and can produce 13.84g / L of dry cells and about 88.99mg / L of total lipid A; total lipid A contains only two structures, namely MPL and D-MPLA.

The invention relates to an enriched population of modified lipopolysaccharide (LPS) molecular species being: - devoid of phosphate group at position C1 of the reducing end of their lipid A domain; and - substituted at position C6' of the non-reducing end of their lipid A domain by a hydrophilic moiety, with the proviso that said hydrophilic moiety is not a hydroxyl group. It also relates to compositions comprising the enriched population of modified LPS; and uses of naturally-occurring LPS molecular species and / or enriched population of modified LPS molecular species for treating and / or preventing cancer, inflammatory diseases or infectious diseases, and for stimulating an immune response or vaccinating a subject.

The invention belongs to the technical field of biological medicines, and particularly relates to a universal vaccine constructed by taking lipopolysaccharide or analogues thereof as universal antigens and adjuvants, the vaccine can establish inherent immune memory and adaptive immune memory at the same time after being inoculated, instant quick prevention and control can be realized aiming at sudden epidemic situations, and the immunologic function of the vaccine is improved. And a plurality of diseases can be prevented or treated. Besides, the lipopolysaccharide analogue and an amphiphilic substance are assembled into nanoparticles by utilizing the hydrophobicity of a lipid A structure of the lipopolysaccharide analogue and the hydrophilicity of a glycosyl group, and through ligand modification, the targeting property of the vaccine to antigen presenting cells is improved, and the safety of the lipopolysaccharide or the analogue thereof in application to universal vaccines, adjuvants and medicines is improved.

The invention relates to the technical field of medicines, in particular to monophosphate lipid A as well as a synthesis method and application thereof. The monophosphate lipid A is shown as a formula I; the synthesis method comprises the following steps: constructing engineering bacteria for producing the monophosphate lipoid A, and carrying out metabolism extraction on the engineering bacteria to obtain the monophosphate lipoid A as shown in the formula 1. According to the method, the production cost of KMA is reduced by utilizing the constructed engineering strain, pathogenic bacteria are not involved in the production process, an inducer is not needed, and the method can be used for large-scale production of attenuated KMA. The attenuated KMA enhances the IgG antibody level of an influenza vaccine immunized mouse, and has better immunologic adjuvant activity on the influenza vaccine.

A linker comprising both a diazo group and a ketone group capable of directly conjugating phosphodiester and sulfate groups on biomolecules using the diazo group, thereby enabling the functionalization of phosphate and sulfate-containing biomolecules via oxime bond formation. The linker is compact and volatile, facilitating easy cleanup by vacuum, which in turn minimizes sample loss and improves experimental operations. The linker exhibits high derivatization efficiency and chemoselectivity, accommodating a variety of functional groups on the biomolecules. By coupling the linker with isobaric mass tags, multiplexed quantitative analysis can be achieved for an extensive variety of lipid classes.

A carboxylic acid-type lipid can accelerate adhesion or aggregation of platelets even if the carboxylic acid-type lipid does not carry a protein involved in adhesion or aggregation of platelets or a peptide corresponding to an active site of the protein; a lipid particle and a lipid membrane each include the carboxylic acid-type lipid; and a platelet aggregation accelerating agent, a platelet adhesion accelerating agent, a hemostatic agent and a platelet substitute each include the carboxylic acid-type lipid, the lipid particle or the lipid membrane. A carboxylic acid-type lipid is selected from carboxylic acid-type lipids represented by formulas (I) to (VI), a lipid particle includes the carboxylic acid-type lipid, a lipid membrane includes the carboxylic acid-type lipid, and a platelet aggregation accelerating agent, a platelet adhesion accelerating agent, a hemostatic agent and a platelet substitute each include the carboxylic acid-type lipid, the lipid particle or the lipid membrane.

An in vitro method of detecting one or more endotoxins of one or more pathogens in a sample, comprising the steps of a. coating a lipid binding protein on a substrate or capturing a lipid binding protein on a capture molecule immobilized on a substrate, b. contacting the lipid binding protein, thus coated or captured, with the sample, c. detecting whether an endotoxin binds to the lipid binding protein, wherein the one or more endotoxins comprise a lipid A moiety and O- polysaccharide moiety, wherein the lipid binding protein is capable of binding the lipid A moiety of an endotoxin, and characterized in that the lipid binding protein is a mammalian protein and preferably is a murine or human protein.

The present invention discloses a recombinant Escherichia coli capable of producing a monophosphate lipid A vaccine adjuvant, belonging to the fields of genetic engineering and synthetic biology. The present invention knocks out the mlaE and pldA genes of the phospholipid transport system on the Escherichia coli MG1655 genome, the hns gene that regulates PagP expression, and sequentially integrates the FnlpxE gene from Francisella and the SepagL gene from Salmonella by deletion and replacement of other phospholipid transport-related gene clusters ybgC-cpoB and letAB, thereby obtaining the recombinant bacterium WZM012. Through simple fermentation, the WZM012 strain can efficiently synthesize hexaacylated monophosphate lipid A (MPL), producing 32.76 mg / L of MPL in 24 hours of fermentation, with the proportion of MPL in the total lipid A reaching 70%.

The invention discloses a novel Kdo-MPLA adjuvant, and relates to the technical field of synthetic biology, the adjuvant is formed by connecting monophosphate lipid A (MPLA) and Kdo sugar through an alpha-glucosidic bond, MPLA is of a structure formed by modifying salmonella lipid A through 4 '-site monophosphorylation, and the Kdo sugar is endowed with amphipathy, so that the Kdo sugar is self-assembled into liposome nanoparticles in an aqueous solution; the rfaC and eptA genes are double knocked out through a gene editing salmonella attenuated strain, wherein the rfaC knockout blocks the synthesis of LPS core polysaccharide, and lipid A-Kdo connection is reserved; knocking out eptA to obtain a monophosphorylated lipid A; after the engineering bacteria are fermented, high-purity Kdo-MPLA is obtained by adopting a phenol-chloroform-petroleum ether extraction method, the process is simplified, and the product is uniform; the adjuvant can activate a TLR4 signal channel and induce Th1 type immune response, the levels of inflammatory factors IL-6 and IL-1beta are remarkably lower than those of natural LPS, and the adjuvant is suitable for a mixed preparation of vaccine antigens such as HPV and malaria; the method overcomes the defects of hydrolysis uncontrollability and high chemical synthesis cost of the traditional MPLA chemical extraction process.

This invention discloses a single-chain antibody 3G4 that targets and binds to mobile polymyxin resistance proteins and its applications. The amino acid sequence of single-chain antibody 3G4 is shown in SEQ ID NO.2. The mobile polymyxin resistance proteins are MCR-1 and / or MCR-2 proteins. Single-chain antibody 3G4 can specifically bind to the functional catalytic region of the mobile polymyxin resistance proteins, thereby inhibiting their function. Single-chain antibody 3G4, its encoding gene, and an expression vector containing the encoding gene can be used to prepare detection reagents for mobile polymyxin resistance proteins or recombinant bacteria with inhibited polymyxin resistance. The recombinant bacteria are Gram-negative bacteria capable of expressing single-chain antibody 3G4. The single-chain antibody 3G4 provided by this invention can efficiently target polymyxin resistance proteins, blocking their modification of lipid A on the outer membrane of Gram-negative Enterobacteriaceae, thereby reversing bacterial resistance to polymyxins.

The present invention relates to immunogenic compositions comprising Salmonella enterica paratyphoid A serotype outer membrane vesicles (OMV), vaccines comprising said immunogenic compositions, and methods and uses of said immunogenic compositions. The invention also relates to Salmonella paratyphi A bacteria comprising the modified lipid A.

The invention discloses a method for carrying out low endotoxin transformation on salmonella choleraesuis and application of the method, and relates to the field of vaccine.Lipid A of a salmonella choleraesuis attenuated strain SC014 is modified through a genetic engineering technology, low endotoxin transformation is carried out on the salmonella choleraesuis, and a salmonella choleraesuis mutant with low endotoxin is successfully constructed. The modified salmonella choleraesuis and the outer membrane vesicle thereof can effectively activate immune response while obviously reducing the activity of endotoxin, so that the safety and the effectiveness are both considered, and a new thought and a new method are provided for developing a novel vaccine.

The invention belongs to the technical field of biology, and discloses an endotoxin attenuated escherichia coli expression strain which lacks WaaF, WaaC and LpxM and carries at least one of exogenous genes lpxE and lpxF. According to the invention, by preparing the escherichia coli expression strain lacking WaaF, WaaC and LpxM genes at the same time, the dephosphorylation rate of lipoid A of the expression strain is increased, the phosphorylation ability of lipoid A is reduced, and meanwhile, the phosphorylation ability of lipoid A is improved. Through common deletion of the genes, the resistance of the strain to polymyxin B is obviously improved. In addition, the invention further discloses a construction method of the endotoxin weakened escherichia coli expression strain and application of the endotoxin weakened escherichia coli expression strain.

The present invention discloses a bacterium for producing pyranose glucopyranose lipid A or its derivatives, wherein the bacterium is a Gram-negative bacterium, in which a protein for adding a secondary C12 acyl chain at the 2' position of the lipid A structure during the synthesis of lipid A is replaced by a protein for adding a secondary C14 hydroxy acyl chain at the 2' position of the lipid A structure. The present invention synthesizes pyranose glucopyranose lipid A or its derivatives in microorganisms for the first time by modifying Gram-negative bacteria, the overall steps are simple, the cost is greatly reduced compared to the chemical synthesis of GLA, and the invention has good application prospects.

The application discloses a novel Kdo-MPLA adjuvant, relates to the technical field of synthetic biology, and discloses that the adjuvant is composed of monophosphoryl lipid A (MPLA) and Kdo sugar through an alpha-glycosidic bond, the MPLA is a structure of Salmonella lipid A modified by monophosphorylation at a 4' position, and the Kdo sugar is endowed with amphiphilicity, so that the Kdo sugar is self-assembled into a liposome nanoparticle in an aqueous solution; the attenuated strain of Salmonella is edited by double knockout of rfaC and eptA genes: the rfaC knockout blocks the synthesis of LPS core polysaccharide and retains the lipid A-Kdo connection; the eptA knockout obtains monophosphorylated lipid A; after fermentation of the engineering bacteria, high-purity Kdo-MPLA is obtained by using a phenol-chloroform-petroleum ether extraction method, the process is simplified, and the product is uniform; the adjuvant can activate a TLR4 signal pathway and induce a Th1 type immune response, and the levels of inflammatory factors IL-6 and IL-1beta are significantly lower than those of natural LPS, so that the adjuvant is suitable for a mixed preparation of HPV, malaria and other vaccine antigens; and the application overcomes the uncontrollability of hydrolysis and the high cost defect of chemical synthesis of a traditional MPLA chemical extraction process.

Provided herein are compounds of Formula (I), or salts thereof. Also disclosed are compositions, kits, and methods / uses. Exemplary uses include treating diseases (e.g., inflammation, autoimmune diseases) and as immunostimulatory compounds and compositions.

To provide a novel treatment method for benign nervous system tumors, including schwannomas; and to provide a composition for use in the treatment method.SOLUTION: Provided herein are methods for a treating a subject having or at risk of having a benign nervous system tumor. The methods include administering to the subject a therapeutically effective amount of a composition comprising live attenuated Salmonella bacteria, optionally in combination with an immune checkpoint inhibitor and / or angiogenesis inhibitor. Preferably, the attenuated Salmonella is an attenuated strain of S. typhimurium, e.g., Salmonella enterica serovar typhimurium strain VNP20009 with modified lipid A (msbB-) and purine auxotrophic mutation (purI-).SELECTED DRAWING: None

The present invention provides a method of treating sepsis in a subject, comprising administering to the subject an effective amount of a compound of the formulawherein R1 and R2 may be H, OH, protonated phosphate, a phosphate salt, a sugar phosphonate, or a mono-, di- or poly-saccharide,R3 may be OH or a mono-, di- or poly-saccharide,R4, R5, R6 and R7 may be an alkyl or alkenyl chain of up to 13 carbons (for a chain of 16 carbons), andR8, R9, R10 and R11 may be H, OH, or an alkyl or alkenyl ester of up to 16 carbons, or a salt thereof.

A vaccine platform using a Yersinia pestis mutant synthesizing an adjuvant form lipid A (monophosphoryl lipid A, MPLA) for the increased biogenesis of bacterial outer membrane vesicles (OMVs). To enhance the immunogenicity of the OMVs, an Asd-based balanced-lethal host-vector system was constructed to oversynthesize the LcrV antigen of Y. pestis, raise the amounts of LcrV enclosed in OMVs by Type II secretion system, and eliminate harmful factors like plasminogen activator (Pla) and murine toxin from the OMVs. Vaccination with OMVs containing MPLA and increased amounts of LcrV with diminished toxicity afforded complete protection in mice against subcutaneous challenge and intranasal challenge and was significantly superior to that resulting from vaccination with LcrV / alhydrogel. Additionally, the Yersinia OMV can be used as a platform to deliver the heterologous antigens of Bacillus anthraces. Vaccination with multiantigenic self-adjuvanting bionanoparticles from Pseudomonas was also successfully tested in connection with Pseudomonas aeruginosa.

The present invention relates to an immunogenic composition containing outer membrane vesicles (OMVs) of Bacillus paratyphi A, a vaccine containing the immunogenic composition, and a method and use of the immunogenic composition. The present invention also relates to Bacillus paratyphi A containing modified lipid A.

An in vitro method of detecting one or more endotoxins of one or more pathogens in a sample, comprising the steps of a. coating a lipid binding protein on a substrate or capturing a lipid binding protein on a capture molecule immobilized on a substrate, b. contacting the lipid binding protein, thus coated or captured, with the sample, c. detecting whether an endotoxin binds to the lipid binding protein, wherein the one or more endotoxins comprise a lipid A moiety and O- polysaccharide moiety, wherein the lipid binding protein is capable of binding the lipid A moiety of an endotoxin, and characterized in that the lipid binding protein is a mammalian protein and preferably is a murine or human protein.

The present invention is directed to a method for detecting the presence or absence of a bacterium resistant to a cyclic cationic polypeptide antibiotic, comprising: (a) subjecting a test sample to mass spectrometry analysis and generating a mass spectrum output; wherein said test sample comprises a bacterial membrane or a fragment thereof, wherein the fragment comprises a non-Lipid A component; (b) identifying in said mass spectrum output a first defined peak indicative of the presence of Lipid A modified by phosphoethanolamine, wherein said first defined peak is a peak present in a mass spectrum output for Lipid A modified by phosphoethanolamine and wherein said first defined peak is absent from a corresponding mass spectrum output for native Lipid A; and (c) wherein the presence of said first defined peak indicates the presence of a bacterium resistant to a cyclic cationic polypeptide antibiotic, and wherein the absence of said first defined peak indicates the absence of a bacterium resistant to a cyclic cationic polypeptide antibiotic. This method is also used in a screening method to identify an inhibitor of cyclic cationic polypeptide antibiotic resistance in a bacterium. The matrix solution can contain 2,5-dihydroxybenzoic acid and aids in the selective extraction, co-crystallisation and ionisation of native Lipid A and / or modified Lipid A as an integral part of a bacterial membrane.

Metastable liposomal formulations for hydrophobic drug delivery to a tissue or tissue lumen such the bladder have been developed. These are at least one micron in diameter and formed of one or more lipids having entrapped in the lipid a hydrophobic therapeutic, prophylactic or diagnostic agent. The greater stability of these liposomes, as well as the enhanced transfer of entrapped agent into the adjacent tissue, provides for better delivery, especially of hydrophobic agents such as tacrolimus which does not penetrate tissue well. The metastable liposomal formulations can be administered locally, preferably by instillation, or topically, for example, by spraying or painting, to a tissue or tissue lumen such as the bladder in need of treatment.

The invention discloses a preparation method and application of salmonella choleraesuis bionic vesicles capable of being used for oral delivery of double antigens, and relates to the field of vaccines.Lipid A of a salmonella choleraesuis attenuated strain SC014 is modified through a genetic engineering technology, low-endotoxin salmonella choleraesuis engineering bacteria are obtained, then SpyCatcher and SpG are expressed on the surfaces of the salmonella choleraesuis engineering bacteria at the same time through ClyA, and the salmonella choleraesuis bionic vesicles are obtained. According to the present invention, the subunit vaccine model GDH-SpyTag and gD-Fc of the clinically common mixed infection pathogen Streptococcus suis and Pseudorabies virus (PRV) can be respectively coupled, and the negative electricity characteristic of the surface of the subunit vaccine model GDH-SpyTag and gD-Fc are used to wrap the subunit vaccine model GDH-SpyTag and gD-Fc by using the cationic compound COS so as to protect the antigen from being damaged by the gastrointestinal tract environment after the oral immunization; and the presentation of the antigen to digestive tract mucosa immune cells is promoted.

Described herein are methods of synthesizing ionizable amine lipids, such as Lipid A: Formula (I) with increased overall purity, process robustness and an applied impurity control strategy, leading to a substantially pure Lipid A product. Intermediate compounds and methods of synthesizing intermediate compounds are also described.

The invention pertains to a genetically modified Neisseria bacterium comprising a lipopolysaccharide (LPS) having a lipid A moiety and a modified oligosaccharide core, wherein the modified oligosaccharide core comprises a first oligosaccharide chain coupled to heptose 1 and a second oligosaccharide chain coupled to heptose 2, wherein the first and second oligosaccharide chain comprise a lactose directly coupled to respectively heptose 1 and 2, thereby forming a Neisseria gonorrhoeae 2C7 epitope. The modified bacterium may express a further non-native N. gonorrhoeae antigen, such as MetQ, AniA or NspA. The modified Neisseria bacterium is not Neisseria gonorrhoeae. The bacterium is preferably Neisseria meningitidis, Neisseria lactamica or Neisseria cinerea. The invention further pertains to LPS and OMVs obtained from the genetically modified bacterium, as well as methods for producing said modified bacterium.

The invention discloses an application of Incyclinide and colistin in preparation of a bactericidal drug for enterobacteriaceae bacteria carrying a mcr (mcr) gene. Incyclinide (Ini) is a chemically modified tetracycline derivative, the invention proves that Ini can recover the bactericidal effect of colistin on enterobacteriaceae bacteria carrying mcr genes in vitro and in animal models, and mechanism analysis shows that Ini recovers the drug effect of colistin by inhibiting lipid A modification, inducing oxidative damage and dissipating proton power (PMF). As a colistin adjuvant, Ini has huge potential in the aspect of resisting enterobacteriaceae bacteria carrying mcr genes.

The present application describes a new class of vaccine adjuvants, which have the 2,4-nitrodiphenyl (DNP) group or an immunologically active sugar moiety, such as rhamnose (Rha) or α-galactose (α-Gal) epitope covalently linked to monophosphoryl lipid A (MPLA). DNP, Rha, α-Gal, and MPLA are potent immunostimulants / adjuvants that function through different mechanisms. The covalent linkage of DNP, Rha, or α-Gal with MPLA generates synergistic effects for stimulating the immune system, thereby creating more potent adjuvants.