Abstract
Chimeric antigen receptor (CAR)-modified T-cell therapy has shown enormous clinical promise against blood cancers, yet efficacy against solid tumors remains a challenge. Here, we investigated the potential of a new combination cell therapy, where tumor-homing induced neural stem cells (iNSCs) are used to enhance CAR-T-cell therapy and achieve efficacious suppression of brain tumors. Using in vitro and in vivo migration assays, we found iNSC-secreted RANTES/IL-15 increased CAR-T-cell migration sixfold and expansion threefold, resulting in greater antitumor activity in a glioblastoma (GBM) tumor model. Furthermore, multimodal imaging showed iNSC delivery of RANTES/IL-15 in combination with intravenous administration of CAR-T cells reduced established orthotopic GBM xenografts 2538-fold within the first week, followed by durable tumor remission through 60 days post-treatment. By contrast, CAR-T-cell therapy alone only partially controlled tumor growth, with a median survival of only 19 days. Together, these studies demonstrate the potential of combined cell therapy platforms to improve the efficacy of CAR-T-cell therapy for brain tumors.