Date of Graduation
Masters of Science (MS)
Dean Lee MD PhD
Muzaffar Qazilbash MD
Padmanee Sharma MD PhD
Robert Bast MD
Partow Kebriaei MD
Laurence Cooper MD PhD (non voting member)
Introduction: Cellular therapy has shown great potential in early phase clinical trials with persistence of effector cells appearing to lead to improved outcomes. Combined immunotherapy with NY-ESO-1+ CAR T cells (TCR mimetic) and an NY-ESO-1 specific T-APC vaccine in myeloma patients may lead to enhanced anti-myeloma efficacy due to improved persistence of the CAR T cells.
Materials and Methods: Using the Sleeping Beauty transposon/transposase system, an NY-ESO-1+ TCR and CAR were created as effector cells. Vaccine was produced by electroporation of the NY-ESO-1 gene into T cells to make T cell antigen presenting cells (T-APC). Costimulatory molecules were added to the T-APC to help improve immunization efficacy. In vitro studies were conducted to evaluate the ability of T-APC to expand antigen specific effector cells compared to a positive control of K562 artificial antigen presenting cells (aAPC). The ability of effector cells (TCR versus CAR) to kill the U266 myeloma cell line and other targets was also evaluated. An MRD multiple myeloma mouse model using a U266 cell line was used to compare delayed tumor growth for CAR versus CAR+T-APC.
Results: NY-ESO-1+ T-APC with mIL-15 were successfully generated with >95% expression of the antigen and co-stimulatory molecule. In vitro studies confirmed the NY-ESO-1+ CAR expanded upon co-culture with T-APC and lysed the U266 line more efficiently than the NY-ESO-1+ TCR. Subsequent in vivo studies revealed the NY-ESO-1 CAR delayed tumor growth significantly when compared to the control tumor only group and irrelevant CAR control CD19R+ CAR group. The NY-ESO-1+ CAR + T-APC group showed similar tumor delay using bioluminescent imaging, but improved tumor control on necropsy compared to the NY-ESO-1+ CAR alone group. The NY-ESO-1+ CAR + T-APC group also showed increased persistence of CAR+ T cells with memory phenotype compared to all other experimental cohorts.
Conclusion: NY-ESO-1+ T-APC work similarly to K562 aAPC in expanding NY-ESO-1+ CAR T cells in vitro, and lead to improved persistence of CAR T cells and anti-myeloma effect in vivo.
cellular therapy, multiple myeloma, CAR T cells, cancer vaccines, NY-ESO-1, T-APC