A preparing method of a recombinant fusion protein modified with bacterial polysaccharides and applications thereof

Abstract

A preparing method of a recombinant fusion protein modified with bacterial polysaccharides and applications thereof are disclosed. The method includes co-expressing a recombinant fusion protein and neisseria meningitide O-oligosaccharyltransferase PglL in a bacterium with O-antigen ligase gene defect, and allowing polysaccharides of the bacterium or exogenous polysaccharides to be connected to the recombinant fusion protein through the neisseria meningitide O-oligosaccharyltransferase PglL to obtain the recombinant fusion protein modified with the bacterial polysaccharides. A specific antibody resisting bacterial polysaccharides can be prepared through immunizing mice with the prepared recombinant fusion protein modified with the bacterial polysaccharides. Through applying the recombinant fusion protein modified with the bacterial polysaccharides to preparation of bacterial polysaccharide protein conjugate vaccines, a plurality of problems of culturing of pathogenic bacteria can be avoided, homogeneity and a production efficiency of the vaccines can be increased and a vaccine preparing cost can be reduced.

Description

technical field [0001] The invention relates to a preparation method and application of a polysaccharide-modified protein; in particular to a preparation method and application of a bacterial polysaccharide-modified recombinant fusion protein, which belongs to the field of biomedicine. Background technique [0002] O polysaccharide (OPS) and capsular polysaccharide (CPS) of pathogenic bacteria are often important protective antigens, such as Escherichia coli O157 OPS, Vibrio cholerae O1 and O139 OPS, Streptococcus pneumoniae type 4, 6B, 9V, 14, 18C, 19F, 23F CPS, etc., CP5 and CP8 CPS of Staphylococcus aureus, and so on. Many antibodies against polysaccharides are neutralizing antibodies to pathogenic bacteria, so the development of polysaccharide vaccines has always been one of the focuses of bacterial vaccine research and development. [0003] A number of polysaccharide vaccines such as pneumonia polysaccharide vaccine, meningitis polysaccharide vaccine, Haemophilus influ...

AI Technical Summary

Problems solved by technology

The process has the following problems: ①Large-scale cultivation of attenuated vaccine strains of pathogenic bacteria to extract polysaccharides has certain safety risks, and sometimes negative pressure workshops are required, while for severe pathogens, it is often only after obtaining attenuated strains of pathogenic bacteria that they can be extracted through large-scale cultivation Polysaccharides; ②The polysaccharides extracted by chemical methods are mixtures with low purity, difficult quality control, and easy to cause side reactions; ③The cross-linking of polysaccharides and carrier proteins is a random process, the product uniformity is poor, and purification and quality control are difficult; ④Production process steps Many, low yield, high cost

However, there are few studies on the specificity of PglL to protein substrates. At present, its known substrate is only Neisserial pilus protein PilE, which limits its use in the preparation of polysaccharide-modified protein vaccines.

Images