Document Type : Original Article
Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
Department of Biology, Faculty of Science, University of Guilan, Rasht, Iran
Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
Department of Anatomical Sciences, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
Advanced Therapy Medicinal Product Technology Development Center (ATMP-TDC), Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
Objective: Chimeric antigen receptor (CAR) T cell therapy has recently emerged as a promising approach for the
treatment of different types of cancer. Improving CAR T cell manufacturing in terms of costs and product quality is an
important concern for expanding the accessibility of this therapy. One proposed strategy for improving T cell expansion
is to use genetically engineered artificial antigen presenting cells (aAPC) expressing a membrane-bound anti-CD3 for
T cell activation. The aim of this study was to characterize CAR T cells generated using this aAPC-mediated approach
in terms of expansion efficiency, immunophenotype, and cytotoxicity.
Materials and Methods: In this experimental study, we generated an aAPC line by engineering K562 cells to express
a membrane-bound anti-CD3 (mOKT3). T cell activation was performed by co-culturing PBMCs with either mitomycin
C-treated aAPCs or surface-immobilized anti-CD3 and anti-CD28 antibodies. Untransduced and CD19-CARtransduced
T cells were characterized in terms of expansion, activation markers, interferon gamma (IFN-γ) secretion,
CD4/CD8 ratio, memory phenotype, and exhaustion markers. Cytotoxicity of CD19-CAR T cells generated by aAPCs
and antibodies were also investigated using a bioluminescence-based co-culture assay.
Results: Our findings showed that the engineered aAPC line has the potential to expand CAR T cells similar to that
using the antibody-based method. Although activation with aAPCs leads to a higher ratio of CD8+ and effector memory
T cells in the final product, we did not observe a significant difference in IFN-γ secretion, cytotoxic activity or exhaustion
between CAR T cells generated with aAPC or antibodies.
Conclusion: Our results show that despite the differences in the immunophenotypes of aAPC and antibody-based CAR T
cells, both methods can be used to manufacture potent CAR T cells. These findings are instrumental for the improvement
of the CAR T cell manufacturing process and future applications of aAPC-mediated expansion of CAR T cells.