Cell activation-dependent secretion system and application

Abstract

The invention aims to provide a cell activation-dependent secretion system. The system can be used in various aspects such as cell signal transduction research, protein molecule expression research, tumor immunotherapy and the like after combination of various receptor ligands. The cell activation-dependent secretion system comprises a cell and a carrier, the carrier expresses a secretion element capable of being secreted to a cell membrane or the periphery of the cell after being introduced into the cell, and the secretion element is cut by a cutting molecule generated after the cell is activated. Particularly, the CAR-T / NK cell activation-dependent immunotherapy system constructed according to a method can only secrete effector molecules at a local part of a tumor, so that the CAR-T / NK cell activation-dependent immunotherapy system is used for resisting the influence of a tumor microenvironment and even changing the tumor microenvironment, the treatment effect and safety of tumor immunotherapy can be improved, and the toxicity can be reduced.

Description

technical field [0001] The invention relates to the fields of cell biology and immunotherapy, and more specifically, the invention relates to a cell activation-dependent secretion system and its application. Background technique [0002] At present, tumor immunotherapy represented by immune checkpoint inhibitors has brought significant survival benefits to some tumor patients, but most patients do not respond well to it or have primary resistance [1] . Therefore, the world is accelerating the development of various new immunotherapy methods. Chimeric antigen receptor (CAR) immune cells, as a genetically engineered immune cell therapy method, can kill tumors precisely, quickly and efficiently, and become a promising new tumor immunotherapy method [2] . At present, CAR-modified T cells (CAR-T) have achieved amazing efficacy in hematological malignancies, however, due to the selection of tumor-specific antigen targets, limited intratumoral infiltration, and intratumoral immu...

AI Technical Summary

Problems solved by technology

[0005] The purpose of TURCK CAR-T technology is to induce the expression and secretion of target cytokines by combining CAR-T cells with target antigens and activating them, so as to make the cytokines accumulate in the tumor tissue as much as possible and reduce the systemic toxicity caused by peripheral secretion; however, This TRUCK T cell technology has big safety risks [8] , mainly due to "leakage" of the NFAT promoter, NFAT activation triggered by the T cell's own TCR (endogenous TCR), and CD3 signaling-independent NFAT activation (see Image 6 ) [8-10]

An early clinical trial using TRUCK technology to inducibly express IL-12 to engineer tumor-infiltrating lymphocytes (TILs) adoptively treat melanoma, although it showed obvious therapeutic advantages, it produced a lot of toxicities including liver damage, Hyperthermia and hemodynamic disturbance [11] ; High levels of IL-12 were detected in the patient's serum, suggesting that IL-12 secreted into the circulatory system produced systemic toxicity

In addition, the promoters used for CAR expression and cytokine-inducible expression cassettes must be two different promoters. In order to prevent the inducible expression cassette from being transactivated by the strong constitutive CAR promoter, two viral vector transductions are required. To obtain TRUCK CAR-T cells with CAR and inducible expression cassettes located at different genomic loci, this repeated viral transduction not only increases the complexity of the CAR-T cell process but also impairs T cell activity [8,12]

In summary, the fourth-generation CAR technology cannot truly achieve targeted delivery of immune active molecules, and cannot meet the clinical needs for the safety of CAR-T cell therapy, thus restricting their clinical application

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