P009
Improving exosome production and immunogenicity for more effective CAR T cell therapy
P Heredia(1,6) K Pavlovic(1,2) I C Herrera(2,7) M D Carmona(2) J A Marchal(3,4,5,6) K Benabdellah(1)
1:Department of Genomic Medicine, Pfizer-University of Granada-Andalusian Regional Government Centre for Genomics and Oncological Research (GENYO), Granada, Spain; 2:Maimonides Institute of Biomedical Research in Cordoba (IMIBIC), Cell Therapy, 14004, Cordoba, Spain. 3Department of Hematology, Reina Sofía University Hospital, Cordoba, Spain; 3:Instituto de Investigación Biosanitaria ibs.GRANADA, University Hospitals of Granada – University of Granada, 18016 Granada, Spain; 4:Excellence Research Unit “Modeling Nature” (MNat), University of Granada, 18016 Granada, Spain; 5:Biopathology and Regenerative Medicine Institute (IBIMER), Center for Biomedicinal Research (CIBM), University of Granada, 18016 Granada, Spain; 6:Department of Human Anatomy and Embryology, Faculty of Medicine, University of Granada, Biosanitary Research Institute of Granada (ibs.GRANADA), Granada, Spain; 7:Department of Hematology, Reina Sofía University Hospital, Cordoba, Spain
Immunotherapy using CAR T cells has shown remarkable results in treating hematological malignancies. However, their efficacy in treating solid tumors is challenging. Exosomes have emerged as a promising complementary therapy to overcome this limitation. One such approach is the use of exosomes derived from CAR T cells (EXO-CAR-T). However, the production of homogeneous exosomes with reduced immunogenicity remains a significant challenge. A better understanding of the cellular processes controlling exosome biogenesis and their modulation can aid in producing non-immunogenic exosomes from CAR T cells, thereby enhancing their clinical applicability.
Our assessment involved genetically modifying a T cell line by overexpressing CD63 and HGS, two proteins that play a critical role in exosome formation. Furthermore, we also investigated the potential impact of HLA-I elimination on the allo-reactivity of the T cell-derived exosomes.
Our preliminary data showed that overexpression of HGS and CD63 genes in Jurkat cell lines enhances the EXOs production. On the other hand, our results showed that anti-CD19 CAR-T cells produce functional anti-CD19 CAR T exosomes that could kill tumor cells. Finally, the use of B2MKO T cells in a transwell assay result in a reduction in the proliferation of third-party PBMCs.
Based on the observed increase in exosome production resulting from genetic manipulation of Jurkat cells and the ability of anti-CD19 CAR T exosomes to kill tumor cells, along with the absence of alloreactivity estimated with the transwell assay, it is suggested that exosomes have the potential to be utilized as an off-the-shelf, cell-free approach for cancer therapeutics.