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bioRxiv · 10.1101/2024.11.21.624707

Effective targeting of CD19 positive primary B-ALL cells using CAR-NK cells generated with mRNA-LNPs

Salehi-Shadkami, H.·Sedghi, M.·Tavoosi, S.·Alimohammadi, M.·Alimohammadi, R.·Barkhordar, M.·Mofayezi, A.·Modaresi, M. S.·Vaezi, M.·Dehghanizadeh, S.·Ahmadvand, M.·Khoddami, V.
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Abstract

1.Chimeric antigen receptor natural killer (CAR-NK) cell therapy is recognized as a promising modality for the treatment of hematologic malignancies, particularly B-cell malignancies. In this study, we developed "off-the-shelf" anti-CD19 CAR-NK cells using anti-CD19 CAR mRNAs formulated in proprietary ionizable lipid nanoparticles (LNPs). The efficiency of mRNA-LNP delivery into umbilical cord blood (UCB)-derived NK cells and primary T cells was evaluated in an in-vitro setting, demonstrating superior delivery efficiency in NK cells. Further investigation showed a probable role for an endocytic mechanism, macropinocytosis, in efficient transfection of NK cells with LNPs. Nevertheless, CAR-NK cells generated through this mRNA-LNP platform exhibited significantly enhanced cytotoxicity against CD19+ target cells, such as EGFP+Raji stable cell line and primary malignant B cells derived from refractory/relapsed B-cell acute lymphoblastic leukemia (B-ALL) patients. These findings highlight the promise of the mRNA-LNP platform in advancing CAR-NK therapies against B-cell malignancies.

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Salehi-Shadkami, H., Sedghi, M., Tavoosi, S., Alimohammadi, M., Alimohammadi, R., Barkhordar, M., Mofayezi, A., Modaresi, M. S., Vaezi, M., Dehghanizadeh, S., Ahmadvand, M., Khoddami, V.. 2024-11-21. Effective targeting of CD19 positive primary B-ALL cells using CAR-NK cells generated with mRNA-LNPs. https://doi.org/10.1101/2024.11.21.624707

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