AUTHOR=Colamartino Aurelien B. L. , Lemieux William , Bifsha Panojot , Nicoletti Simon , Chakravarti Nitin , Sanz Joaquín , Roméro Hugo , Selleri Silvia , Béland Kathie , Guiot Mélanie , Tremblay-Laganière Camille , Dicaire Renée , Barreiro Luis , Lee Dean A. , Verhoeyen Els , Haddad Elie 

TITLE=Efficient and Robust NK-Cell Transduction With Baboon Envelope Pseudotyped Lentivector

JOURNAL=Frontiers in Immunology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2019.02873

DOI=10.3389/fimmu.2019.02873

ISSN=1664-3224

ABSTRACT=<p>NK-cell resistance to transduction is a major technical hurdle for developing NK-cell immunotherapy. By using Baboon envelope pseudotyped lentiviral vectors (BaEV-LVs) encoding eGFP, we obtained a transduction rate of 23.0 ± 6.6% (mean ± SD) in freshly-isolated human NK-cells (FI-NK) and 83.4 ± 10.1% (mean ± SD) in NK-cells obtained from the NK-cell Activation and Expansion System (NKAES), with a sustained transgene expression for at least 21 days. BaEV-LVs outperformed Vesicular Stomatitis Virus type-G (VSV-G)-, RD114- and Measles Virus (MV)- pseudotyped LVs (<italic>p</italic> &lt; 0.0001). mRNA expression of both BaEV receptors, ASCT1 and ASCT2, was detected in FI-NK and NKAES, with higher expression in NKAES. Transduction with BaEV-LVs encoding for CAR-CD22 resulted in robust CAR-expression on 38.3 ± 23.8% (mean ± SD) of NKAES cells, leading to specific killing of NK-resistant pre-B-ALL-RS4;11 cell line. Using a larger vector encoding a dual CD19/CD22-CAR, we were able to transduce and re-expand dual-CAR-expressing NKAES, even with lower viral titer. These dual-CAR-NK efficiently killed both CD19<sup>KO</sup>- and CD22<sup>KO</sup>-RS4;11 cells. Our results suggest that BaEV-LVs may efficiently enable NK-cell biological studies and translation of NK-cell-based immunotherapy to the clinic.</p>