Construction method and application of chimeric antigen receptor (CAR) based on BMCA nano-antibody sequence

Abstract

The invention relates to the technical field of cellular immunity and discloses a construction method and application of a chimeric antigen receptor (CAR) based on a BMCA nano-antibody sequence. The construction method comprises the following steps: step 1: constructing a BMCA single domain antibody library; step 2: screening a BMCA specific nano-antibody sequence; step 3: preparing chimeric antigen receptor T cells. The chimeric antigen receptor is mainly applied to tumor treatment medicines; tumors are tumor diseases related to blood and the tumor diseases related to the blood mainly comprise various leukemia and malignant lymphomas. According to the construction method and application of the chimeric antigen receptor based on the BMCA nano-antibody sequence provided by the invention, the prepared nano-antibody expression sequence is shorter and a limited lentiviral vector space is saved; the chimeric antigen receptor T cells which are constructed based on the antibody have better specificity and a stronger tumor killing capability.

Description

technical field [0001] The invention relates to the technical field of cellular immunity, in particular to a construction method and application of a chimeric antigen receptor based on BMCA nanobody sequence. Background technique [0002] In recent years, significant progress has been made in adoptive immunotherapy of tumors based on chimeric antigen receptor (CAR) modified T cells. The modified T cells not only have the ability to target tumor cells, but also overcome the local immunosuppressive microenvironment of the tumor and break the state of host immune tolerance. CAR has been developed to the fourth generation through continuous improvement. The first-generation CAR is mainly composed of scFv and ITAM (usually CD3ζ) that recognize tumor-associated antigens, but due to only CD3ζ activation signal, T cells cannot fully proliferate, and activated T cells have a short survival time in vivo. The second-generation CAR adds a costimulatory molecule such as CD28, CD134, CD...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the deficiencies of the prior art, the present invention provides a method for constructing a chimeric antigen receptor based on the BMCA nanobody sequence and its application, which has a shorter expression sequence of the prepared nanobody and saves limited lentiviral vector space, The chimeric antigen receptor T cells constructed based on this antibody have better specificity and stronger tumor killing ability, which solves the common scFv whose antigen binding region is composed of human or mouse heavy chain and light chain variable regions The problem of longer expression sequences and low tumor killing ability