Method for screening neoantigen or neoantigen coding sequence

Abstract

The invention discloses a method for screening neoantigen or neoantigen coding sequence. According to the method, a to-be-screened neoantigen coding sequence is inserted into an original expression vector to obtain a recombinant expression vector, then immature DC cells are transfected, the transfected DC cells are cultured to obtain mature DC cells which express corresponding neoantigen epitope peptides on the surfaces, new antigen epitope peptides are presented to T cells by the mature DC cells, the T cells are induced to be activated into an effector T cell, the effector T cells are co-cultured with tumor cells to screen for an effector T cell that has good killing effect on tumor cells, so that a neoantigen with good immunogenicity is screened out, and the corresponding coding sequenceis the coding sequence of the screened neoantigens with good immunogenicity. According to the method for screening neoantigen or neoantigen coding sequence, the neoantigen with strong immunogenicitycan be obtained through rapid screening, the corresponding wild-type peptide does not have immunogenicity, and the neoantigen is the best choice for vaccines.

Description

technical field [0001] The invention relates to the field of biotechnology, in particular to a method for screening neoantigens or neoantigen coding sequences. Background technique [0002] The close relationship between tumor occurrence and gene mutation has been confirmed by many studies. Related gene point mutations, fragment deletions and insertions cause codon synonym, missense, termination or frame shift, which will lead to changes in protein sequence or loss of related functions. Abnormal proteins produced by mutations in tumor cells that activate the immune system are called neoantigens. Existing animal and clinical studies have shown that T cells activated by tumor neoantigens can specifically kill tumor cells and produce immune memory effects, thereby partially or completely regressing tumors. [0003] Theoretically, tumor antigens can be processed and presented through two pathways: "endogenous" and "exogenous". Endogenous antigens can be cleaved by intracellul...

AI Technical Summary

Problems solved by technology

However, the neoantigen peptides used in this verification method are almost all short peptides, and their degradation rate in the culture system cannot be evaluated, and it is necessary to verify whether they are effectively presented and activate T cells through killing experiments

In addition, the verification requires the use of cells with specific HLA types, that is, the one-to-one killing verification of primary tumor cells and corresponding T cells cannot be achieved

However, when synthetic neoantigen long peptides are used to screen neoantigens, antigen-presenting cells usually present neoantigen epitope peptides through the MHC II pathway after phagocytosis of long peptides, and activate CD4+ T cells; In tumor immunotherapy, tumor cells are mostly somatic cells, and the peptide-MHC class I complex is presented on the cell surface, so the use of long peptides to screen neoantigens has limitations

[0006]The above factors affect the accuracy of neoantigen screening and often result in the absence of widespread tumor regression in cancer patients treated with neoantigen vaccines

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