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bioRxiv · 10.1101/2025.04.10.648181

Dextran-based T-cell expansion nanoparticles for manufacturing CAR T cells with augmented efficacy

Zheng, T.·Ramanathan, K.·Ormhoj, M.·Hansen, M. R.·Halldorsdottir, H. R.·Li, H.·Munk, K. K.·Rodriguez-Pardo, C.·Friis, R. U. W.·Islam, S. F.·Heegaard, P. M. H.·Qvortrup, K.·Abken, H.·Sun, Y.·Hardup, S. R.
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Abstract

Adoptive T cell therapy (ACT) using chimeric antigen receptor (CAR) engineered T cells is currently being explored in multiple cancer types beyond leukemia/lymphoma. A key step in CAR-T cell manufacturing is the activation and expansion of T cells, which facilitates viral transduction, however, may hamper T cell fitness and reduce in vivo persistence. We developed "T-Expand" for T cell activation and expansion, comprising dextran-based nanoparticles (NPs) conjugated with anti-CD3 and anti-CD28 antibodies. The NPs triggered robust polyclonal expansion of human T cells with efficiency in the range of commercial microbeads (Dynabeads). Engineered in presence of T-Expand, CD19 CAR T cells exhibited enhanced proliferative capacity, cytotoxicity and persistence in vitro, and furthermore, showed superior anti-lymphoma activity in mouse models resulting in complete tumor clearance at one fourth of the CAR T cell dose. Importantly, T-Expand is biocompatible with no observed toxicity, circumventing removal steps after T cell expansion compared to DynabeadsTM. As a biocompatible T cell expansion platform, T-Expand simplifies the manufacturing process while enhancing T cell persistence and functionality, thereby holding promise for increasing clinical efficacy of CAR T cell therapy. O_FIG O_LINKSMALLFIG WIDTH=165 HEIGHT=200 SRC="FIGDIR/small/648181v1_ufig1.gif" ALT="Figure 1"> View larger version (74K): org.highwire.dtl.DTLVardef@35337corg.highwire.dtl.DTLVardef@c75199org.highwire.dtl.DTLVardef@1be184forg.highwire.dtl.DTLVardef@12e1683_HPS_FORMAT_FIGEXP M_FIG Graphical abstract/Cover figureIllustration of CAR T cell manufacturing using T-Expands ex vivo. C_FIG

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Zheng, T., Ramanathan, K., Ormhoj, M., Hansen, M. R., Halldorsdottir, H. R., Li, H., Munk, K. K., Rodriguez-Pardo, C., Friis, R. U. W., Islam, S. F., Heegaard, P. M. H., Qvortrup, K., Abken, H., Sun, Y., Hardup, S. R.. 2025-04-16. Dextran-based T-cell expansion nanoparticles for manufacturing CAR T cells with augmented efficacy. https://doi.org/10.1101/2025.04.10.648181

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