Chimeric receptor and application thereof

The invention relates to a chimeric receptor and application thereof, and the chimeric receptor comprises a first extracellular domain which comprises a domain specifically targeting 4-1BB; and a first transmembrane domain; the chimeric receptor further comprises a first intracellular domain, the first intracellular domain comprising a first co-stimulatory domain and not comprising an activation signal transduction domain; the first extracellular domain further comprises a first hinge region, and the first hinge region is connected with the first transmembrane domain. When the chimeric receptor and a CAR molecule are co-expressed in an immune cell such as a T cell, the in-vivo accessibility is relatively strong, and the killing persistence of the CAR positive immune cell on 4-1-BB positive NK/T cells and CAR target antigen positive cells is enhanced. In addition, immune cells that co-express chimeric receptor CR and CAR molecules exhibit enhanced tumor killing ability, better CAR-T in vivo accessibility and r