As chimeric antigen receptor (CAR)-T cell therapy has been recently applied in clinics, controlling the fate of blood cells is increasingly important for curing blood disorders. In this study, we aim to construct proliferation-inducing and differentiation-inducing CARs (piCAR and diCAR) with two different antigen specificities and express them simultaneously on the cell surface. Since the two antigens are non-cross-reactive and exclusively activate piCAR or diCAR, sequential induction from cell proliferation to differentiation could be controlled by switching the antigens added in the culture medium. To demonstrate this notion, a murine myeloid progenitor cell line 32Dcl3, which proliferates in an IL-3-dependent manner and differentiates into granulocytes when cultured in the presence of G-CSF, is chosen as a model. To mimic the cell fate control of 32Dcl3 cells, IL-3R-based piCAR and G-CSFR-based diCAR are rationally designed and co-expressed in 32Dcl3 cells to evaluate the proliferation- and differentiation-inducing functions. Consequently, the sequential induction from proliferation to differentiation with switching the cytokine from IL-3 to G-CSF is successfully replaced by switching the antigen from one to another in the CARs-co-expressing cells. Thus, piCAR and diCAR may become a platform technology for sequentially controlling proliferation and differentiation of various cell types that need to be produced in cell and gene therapies.
Copyright: © 2022 Nakajima et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.