The invention relates to a chimeric
antigen acceptor of a target BCMA (
B cell maturation
antigen). The chimeric
antigen acceptor comprises an
extracellular identification region, a
hinge region, a
transmembrane region and an
intracellular signal region, wherein the
extracellular identification region has a BCMA resisting nanometer
antibody sequence, and the BCMA resisting nanometer
antibody sequence is a heavy-chain variable region sequence combining with BCMA and from alpacas. More specifically, the BCMA resisting nanometer
antibody sequence is BCMA
monoclonal antibody B1 or B65, the
amino acid sequence of the B1 is as shown in SEQID NO.1, and the
amino acid sequence of the B65 is as shown in SEQID NO.2. According to the chimeric antigen
acceptor disclosed by the invention, compared witha traditional mouse-derived SCFV or humanized SCFV, the nanometer antibody from the alpacas is used, and has
small molecule quantity and
immunogenicity, the possibility that CAR-T cells prepared on the base of the nanometer antibody produce HAMA effects
in vivo is smaller, the remaining time of the CAR-T cells
in vivo can be longer, the CAR-T cells pass through BCMA
protein on the surfaces of target
tumor cells and activate
signal channels at the downstream part of T cells, the capacity for killing
tumor cells having BCMA target points is given to the T cells, and BCMA positive
blood tumor canbe efficiently and specifically treated.