Author ORCID Identifier
Date of Graduation
8-2024
Document Type
Thesis (MS)
Program Affiliation
Biomedical Sciences
Degree Name
Masters of Science (MS)
Advisor/Committee Chair
Raghu Kalluri, MD, PhD
Committee Member
May Daher, MD
Committee Member
Menashe Bar Eli, PhD
Committee Member
Michael Green, MD
Committee Member
Sattva Neelapu, MD
Abstract
Chimeric antigen therapy (CAR T therapy) is an important advance in cancer treatment. It involves leukapheresis to isolate T cells from the patient’s blood, which are then genetically engineered in the laboratory to express a chimeric antigen receptor (CAR) on their surface. This CAR is tailored to recognize a specific antigen, most commonly on cancer cells. In the case of diffuse large B-cell lymphoma, a CD19 CAR is added to the T cells to help them recognize and attach to the cancer B cells presenting that antigen. An immune response is triggered, and tumor cells with the antigen are killed. Despite the proposed specific mechanism involving CAR T therapy, it can have adverse side effects on the body. We hypothesize that exosomes (EVs) isolated from anti-CD19 CAR T cells can specifically induce cytotoxicity via cargo delivery of granzyme B and perforin without significant toxicity. To test this hypothesis, fourteen anti-CD19 CAR-T cells that were used to infuse patients were procured and tested. CAR-T cells and EVs isolated from them were characterized for their unique biomarkers and proteins. As shown using western blots and single particle FACS, the CAR-T exosomes retained the cytotoxic cargo of granzyme B and perforin with the expression of the CAR. Furthermore, cytotoxic and apoptotic assays revealed that EVs present potent cytotoxicity toward B-cell lymphoma cells expressing CD19 compared to control cells. My study suggests that EVs derived from CAR-T cells can be used as potential allogeneic therapy, which will require further pre-clinical testing.
Keywords
CAR-T, exosomes, extracellular vesicles, anti-CD19 CAR-T cells, B-cell lymphoma