Project description:We generated a new B7-H3 CAR-T cell costimulatory domain using TMIGD2 and found it was as good or better than the CD28.4-1BB costimulatory domain. Little is known about TMIGD2 signaling, so we examined how each CAR signals individually compared to CD19.CD28.4-1BB control CAR-T cells.
Project description:CAR-T cell costimualtory domains can alter CAR-T cell phenotypes. We therefore performed RNA sequencing to understand the effect of TMIGD2 vs CD28.4-1BB comstimulation in B7-H3 CAR-T cells after in vitro coculture.
Project description:The tumor microenvironment can significantly alter CAR-T cell phenotypes. We therefore performed RNA sequencing to understand the effect of TMIGD2 vs CD28.4-1BB comstimulation in B7-H3 CAR-T cells after intravenous administration to tumor-bearing mice in vivo.
Project description:Abstract. The use of large animal spontaneous models of solid cancers, such as dogs with osteosarcoma (OS), can help develop new cancer immunotherapy approaches, including chimeric antigen receptor (CAR) T cells. Therefore, the goal of the present study was to generate canine CAR T cells targeting the B7-H3 (CD276) co-stimulatory molecule overexpressed by several solid cancers, including OS and glioma in both humans and dogs, and to assess their ability to recognize B7-H3 expressed by canine OS cell lines or by canine tumors in xenograft models. A second objective was to determine whether a novel dual CAR that expressed a chemokine receptor together with the B7-H3 CAR improved the activity of the canine CAR T cells. Therefore, in the studies reported here we examined B7-H3 expression by canine OS tumors, evaluated target engagement by canine B7-H3 CAR T cells in vitro, and compared the relative effectiveness of B7-H3 CAR T cells versus B7-H3-CXCR2 dual CAR T cells in canine xenograft models. We found that most canine OS tumors expressed high levels of B7-H3, whereas levels were undetectable on normal dog tissues. In vitro, both B7-H3 CAR T cells demonstrated activation and OS-specific target killing in vitro, but there was significantly greater cytokine production by B7-H3-CXCR2 CAR T cells. In canine OS xenograft models, little antitumor activity was generated by B7-H3 CAR T cells, whereas B7-H3-CXCR2 CAR T cells significantly inhibited tumor growth, inducing complete tumor elimination in most treated mice. These findings indicated therefore that addition of a chemokine receptor could significantly improve the anti-tumor activity of canine B7-H3 CAR T cells, and that evaluation of this new dual CAR construct in dogs with primary or metastatic OS is warranted since such studies could provide a critical and realistic validation of the chemokine receptor concept.
Project description:We have employed mRNA microarray expression profiling as a discovery platform to identify genes with the potential to explain how small dose SAHA promoted the cell toxicity of B7-H3 CAR-T cells. B7-H3 CAR-T cells were treated by 0.5μM SAHA for 5 days, and with control samples.
Project description:Vδ1T cells, a rare subset of γδT cells, hold promise for treating solid tumors. Unlike conventional T cells, they recognize tumor antigens independently of the MHC antigen-presentation pathway, making them a potential “off-the-shelf” cell therapy product. However, isolation and activation of Vδ1T cells is challenging, which has limited their clinical investigation. Here, we developed a large-scale clinical-grade manufacturing process for Vδ1T cells and validated the therapeutic potential of B7-H3-CAR-modified Vδ1T cells in treating solid tumors. Co-expression of interleukin-2 with the B7-H3-CAR led to durable anti-tumor activity of Vδ1T cells in vitro and in vivo. In multiple subcutaneous and orthotopic mouse xenograft tumor models, a single intravenous administration of the CAR-Vδ1T cells resulted in complete tumor regression. These modified cells demonstrated significant in vivo expansion and robust homing ability to tumors, akin to natural tissue-resident immune cells.Additionally, the B7-H3-CAR-Vδ1T cells exhibited a favorable safety profile. In conclusion, B7-H3-CAR-modified Vδ1T cells represent a promising strategy for treating solid tumors.