B7-1 + B7-2 gene therapy

B7-1 + B7-2 gene therapy is an investigational gene therapy approach that delivers genes encoding the T cell costimulatory molecules B7-1 (CD80) and B7-2 (CD86) to target cells, commonly in the context of cancer immunotherapy. B7-1 and B7-2 are crucial for T cell activation via interaction with CD28, providing the second signal required for full immune activation. This therapy aims to enhance anti-tumor immunity by increasing co-stimulatory signals to T cells, thereby boosting their activation and proliferation. The approach has included direct injection of recombinant viral vectors encoding B7-1 and/or B7-2 into tumors, as well as transduction of fibroblasts or tumor cells. Preclinical and early clinical studies have shown that gene transfer of B7-1 and B7-2 can induce antitumor responses and immunologic memory in mouse models and in phase I human trials for cancer[3][4][1]. Mechanistically, B7-1/B7-2 interact in cis and trans with PD-L1 and CTLA-4 in the tumor microenvironment, modulating both stimulatory and inhibitory signals. These interactions influence efficacy by enhancing T cell activation through CD28 and reducing immune suppression mediated by PD-1/PD-L1 pathways[1]. Developers have used viral vectors such as recombinant vaccinia and fowlpox viruses to deliver the genes, with studies primarily focused on metastatic cancer settings[3].

Other names

CD80 + CD86 gene therapy