TMIC-55. IMMUNE DIGITAL-SPATIAL PROFILING AND CHARACTERIZATION OF GLIOMA MICROENVIRONMENT AFTER ADOPTIVE CELLULAR THERAPY

Abstract INTRODUCTION Our group has previously shown that Adoptive Cellular Therapy (ACT) is efficacious against CNS malignancies including medulloblastoma, brain stem glioma, and glioblastoma. In this study, we characterized the spatial distribution of immune cells within tumor microenvironment after ACT conducted regional genomic analysis in situ to obtain insights into underlying cellular dynamics. This method enabled us define specific differences gene expression T treated versus untreated tumors changes regulatory cell (Treg) associated genes, such as Runx1 TGF-β. We also found a significant increase Batf3 with therapy. METHODS performed GeoMx Digital Spatial Profiling (DSP) whole genome transcriptomics (RNA) murine glioma KR-158B-luciferase adoptive was orthotopic KR158B tumor-bearing mice. Histological slides were sent be stained for CD45, CD3, GFP (to mark hematopoietic cell-derived cells) nuclei, processed following DSP workflow RNA. Overall clustering profiles using Principal Component Analysis (PCA), relative analyzed by unpaired t-tests. RESULTS/CONCLUSIONS observed differential substantial number genes ACT-treated compared control. findings indicate cluster separately from control PCA analysis. Furthermore, downregulation suppressive properties (Runx1 TGF-β), upregulation dendritic characteristic (Batf3) antigen presentation (H2-Ab1) vs These provide dynamics are differentially expressed microenvironment. could help improve current therapies treat tumors.