Small molecule DNA adaptorprotein for restraining activity of endotoxin

Abstract

The invention provides a small molecule DNA adaptorprotein for restraining the activity of endotoxin and a preparation method thereof. The adaptorprotein is a single chain DNA molecule, characterized in that the nucleotide sequence of its DNA molecule is 5'-GCGTCCACTCCCAGCCGCTCACTAGTTTCTGCGTGGGTGG-3'. The adaptorprotein is obtained by the steps of the establishment of a single chain DNA library, the expansion of the library, storage, the recycling of products of the expansion, twelve rounds of SELEX screening, the cloning with adaptorprotein of LPS affinity and the sequencing. The method provided by the invention can conveniently and accurately acquire the small molecule DNA adaptorprotein which can restrain the activity of endotoxin, and facilitates the mass preparation of the adaptorprotein. The adaptorprotein has the advantages of wide adaptability, non-immunogenicity, strong tissue permeability, little possibility of degrading in human body and easy storage and transportation. The invention can notably restrain the biological activity of endotoxin, provides a novel agonist to prevent and treat sepsis, and lays the foundation for developing novel antiendotoxin medicine.

Description

(1) Technical field [0001] The invention relates to the field of biotechnology, in particular to a small molecule DNA aptamer capable of inhibiting endotoxin activity and a preparation method thereof. (two), background technology [0002] Sepsis is a common complication after severe trauma, shock, and major surgery. Further development can lead to septic shock, multiple organ dysfunction syndrome, etc., and has become an important cause of death in clinical critically ill patients. So far, there is still no special treatment, and the mortality rate remains high. It is one of the difficult and hot issues in the research of trauma surgery and related fields. Studies have shown that: endotoxin [Lipopolysaccharide, LPS] is the cause of G - One of the most important causes of bacterial sepsis and septic shock, LPS and the endotoxemia it causes are G - The main cause or initiating factor of bacterial sepsis and septic shock. Therefore, anti-endotoxin therapy plays an important ...

AI Technical Summary

Problems solved by technology

The strategy of targeting LPS has grasped the key link in the pathogenesis of sepsis. The corresponding preparations have achieved certain effects, and some have entered pre-clinical trials, showing good application prospects, but they have not yet been used in clinical practice.

At the same time, the above-mentioned preparations also have shortcomings to a certain extent: the specificity of the antibody determines that the antibody can only specifically bind to a certain bacterial endotoxin, and has no effect on other bacterial endotoxins; the heterogeneity of the antibody also limits its clinical application. application; there are contradictions between the immunogenicity of the binding protein and its short half-life, easy degradation, and long-term repeated medication; although some preparations have good application prospects, most of them are designed by computer or chemically synthesized, and there are unavoidable effects. The specificity is not high, the antagonistic effect is not strong and other shortcomings

A large number of experiments have proved that under such screening rounds and conditions, it is only possible to obtain aptamers that can bind to LPS, but the high affinity and high specificity of aptamers cannot be guaranteed. The bioactive effect of the toxin is not obvious

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