GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE296nnn/GSE296419/primary200OKTranscriptomicsHomo sapiens OtherExpression profiling by high throughput sequencinghttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE296419GEOGSEfalseThe critical role of the host endogenous immune compartment after intracerebroventricular CAR T cell therapy in recurrent GBMGlioblastoma (GBM) is the most common primary malignant brain tumor in adults, with a median survival of under 15 months and no effective treatment after recurrence. A recent phase I trial of intracerebroventricular (ICV) bivalent CAR T cells in recurrent GBM showed promising responses, including tumor reduction and prolonged survival. However, relapse remains common. We performed in-depth profiling of longitudinal CSF and tumor samples from responders and non-responders to characterize immune dynamics following infusion. Our study reveals that while CAR T cells activate post-infusion across all patients, outcomes were defined by divergent remodeling of the endogenous immune landscape. Cytotoxic NK cell expansion characterized responders, whereas regulatory T cell expansion and abundant baseline immunosuppressive myeloid cells characterized non-responders. These findings indicate that host immune cells play a critical role in ICV CAR T cell therapy for GBM, suggesting that combinatorial strategies modulating the endogenous immune compartment could improve next-generation treatments.2026/06/30GSE296419GSM9543421GSM9543420GSM9543423GSM9543422GSM9543425GSM9543424GSM9543427GSM9543426GSM9543429GSM9543428GSM8970101GSM8970100GSM9543419GSM8970109GSM8970108GSM8970107GSM8970106GSM8970105GSM8970104GSM8970103GSM8970102GSM9543410GSM9543412GSM9543411GSM9543414GSM9543413GSM9543416GSM9543415GSM9543418GSM9543417GSM9543409GSM8970112GSM9543408GSM8970111GSM8970110GSM8970119GSM8970118GSM8970117GSM8970116GSM8970115GSM8970114GSM8970113GSM9543407GSM9543406GSM8970123GSM8970122GSM8970121GSM8970120GSM8970129GSM8970128GSM8970127GSM8970126GSM8970125GSM8970124GSM9543470GSM9543472GSM9543471GSM9543474GSM9543473GSM9543476GSM9543475GSM9543478GSM9543477GSM8970134GSM8970133GSM8970099GSM8970132GSM8970131GSM8970098GSM8970097GSM8970130GSM8970139GSM8970138GSM8970137GSM8970136GSM8970135GSM9543461GSM9543460GSM9543463GSM9543462GSM9543465GSM9543464GSM9543467GSM9543466GSM9543469GSM9543468GSM8970145GSM8970144GSM8970143GSM8970142GSM8970141GSM8970140GSM8970149GSM8970148GSM8970147GSM8970146GSM9543450GSM9543452GSM9543451GSM9543454GSM9543453GSM9543456GSM9543455GSM9543458GSM9543457GSM9543459GSM8970156GSM8970155GSM8970154GSM8970153GSM8970152GSM8970151GSM8970150GSM8970159GSM8970158GSM8970157GSM9543441GSM9543440GSM9543443GSM9543442GSM9543445GSM9543444GSM9543447GSM9543446GSM9543449GSM9543448GSM8970166GSM8970165GSM8970164GSM8970163GSM8970162GSM8970161GSM8970160GSM9543430GSM9543432GSM9543431GSM9543434GSM9543433GSM9543436GSM9543435GSM9543438GSM9543437GSM9543439185732467634281296419Homo sapiens