Conjugate vaccine and preparation method thereof

Abstract

The invention discloses a conjugate vaccine. The conjugate vaccine is formed by conjugation of multivalent pneumococcal polysaccharide and two or more carrier proteins through couplers which are magnetic nanoparticles. According to a preparation method of the conjugate vaccine, the multivalent pneumococcal polysaccharide and the two or more carrier proteins are coupled with the magnetic nanoparticles. The conjugate vaccine is simple in preparation process; by adoption of the magnetic nanoparticles as the couplers, mouse Th1 type immune response can be enhanced while immune persistence, specificity and compatibility of polysaccharide specific antibody can be improved as well, and mice can be induced to generate rotavirus antibodies. Moreover, the conjugate vaccine which has preventive effects of two vaccines has a promising application prospect.

Description

technical field [0001] The invention relates to a vaccine, in particular to a conjugated vaccine vaccine and a preparation method thereof, belonging to the field of biotechnology. Background technique [0002] 1. The harm of microorganisms to the human body and countermeasures [0003] Microorganisms usually refer to those biological groups whose individual volume diameter is generally less than 1mm. They have a simple structure, most of which are single cells, and some do not even have a cell structure. To clarify their morphology and structure; Among them, pathogenic microorganisms refer to pathogenic microorganisms that can cause diseases of humans, animals and plants. The pathogenicity of a pathogen depends on its ability to invade the host and reproduce in vivo and resist host resistance without being eliminated by it. The pathogenicity of microorganisms has species characteristics, and the degree of pathogenicity is called virulence. The establishment of infectious ...

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Problems solved by technology

But this kind of polysaccharide vaccine has the following problems: (1) in young animals or infants, only weak immune response can be produced, or even no immune response, and the immune response will increase with age; (2) produce low-affinity antibodies (3) only produce short-lived immune response, do not have immune memory and immune enhancement effect during repeated vaccination; (4) easy to produce immune tolerance; (5) common adjuvant is not easy to play the role of immune enhancement to this antigen Effect, the 23-valent polysaccharide vaccine has a protection rate of 50-70% for invasive pulmonary chain infection, and can only be used for vaccination of people over 2 years old, while the peak age of onset of pneumonia is 6-12 months old; (6) has Polysaccharides with repeating structures are T cell-independent type 2 immunogens. Without the participation of T cells, they cannot induce immune memory effects, and the antibodies that stimulate the body are mainly IgM and IgG2, which cannot effectively activate the complement system

[0021] However, the above-mentioned traditional polysaccharide-protein binding technology has the following disadvantages: (1) The polysaccharide-AH derivative will continue to react with the polysaccharide activated by cyanogen bromide to form a self-polymer of the polysaccharide, which reduces the polysaccharide-protein binding efficiency; (2) EDAC mediates the combination of ADH-derived polysaccharides and carrier proteins, and at the same time, it is easy to cause self-crosslinking of polysaccharides and carrier proteins, thereby reducing the binding efficiency of polysaccharides and proteins; (3) polysaccharides and carrier proteins are large organisms The molecule is connected by ADH with only 6 carbon atoms in the middle. The structure of polysaccharides and proteins is bound to influence each other, making some important epitopes of polysaccharides easily shielded by proteins, thereby reducing the immunogenicity of polysaccharides

[0041] There are also reports that nano-microspheres can be used as carrier proteins and adjuvants for DNA vaccines, but there is no report on their application in prophylactic polysaccharide and / or protein vaccines

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