NKG2A genetic deletion promotes human primary NK cell anti-tumor responses better than an anti-NKG2A monoclonal antibody.

Publisher: Cell Press Country of Publication: United States NLM ID: 100890581 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1525-0024 (Electronic) Linking ISSN: 15250016 NLM ISO Abbreviation: Mol Ther Subsets: MEDLINE

Publication: 2017- : Cambridge, MA : Cell Press
Original Publication: San Diego, CA : Academic Press, 2000-

Killer Cells, Natural*/immunology ; Killer Cells, Natural*/metabolism ; NK Cell Lectin-Like Receptor Subfamily C*/genetics ; NK Cell Lectin-Like Receptor Subfamily C*/metabolism ; Xenograft Model Antitumor Assays*; Humans ; Animals ; Mice ; Cell Line, Tumor ; HLA-E Antigens ; Neoplasms/immunology ; Neoplasms/therapy ; Neoplasms/genetics ; Antibodies, Monoclonal/pharmacology ; CRISPR-Cas Systems ; Gene Deletion ; Histocompatibility Antigens Class I/immunology ; Histocompatibility Antigens Class I/genetics ; Histocompatibility Antigens Class I/metabolism ; Cytotoxicity, Immunologic

Natural killer (NK) cells eliminate infected or cancer cells via their cytotoxic capacity. NKG2A is an inhibitory receptor on NK cells and cancer cells often overexpress its ligand HLA-E to evade NK cell surveillance. Given the successes of immune checkpoint blockade in cancer therapy, NKG2A is an interesting novel target. However, anti-NKG2A antibodies have shown limited clinical response. In the pursuit of enhancing NK cell-mediated anti-tumor responses, we devised a Cas9-based strategy to delete KLRC1, encoding NKG2A, in human primary NK cells. Our approach involved electroporation of KLRC1-targeting Cas9 ribonucleoprotein resulting in effective ablation of NKG2A expression. Compared with anti-NKG2A antibody blockade, NKG2A ^KO NK cells exhibited enhanced activation, reduced suppressive signaling, and elevated expression of key transcription factors. NKG2A ^KO  NK cells overcame inhibition from HLA-E, significantly boosting NK cell activity against solid and hematologic cancer cells. We validated this efficacy across multiple cell lines, a xenograft mouse model, and primary human leukemic cells. Combining NKG2A knockout with antibody coating of tumor cells further enhanced cytotoxicity through ADCC. Thus, we provide a comprehensive comparison of inhibition of the NKG2A pathway using genetic ablation and antibodies and provide novel insight in the observed differences in molecular mechanisms, which can be translated to enhance adoptive NK cell immunotherapy.
Competing Interests: Declaration of interests G.M.J.B. and W.T.V.G. are the founders of CiMaas BV, an NK cell therapy company.
(Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Keywords: CRISPR-Cas9; HLA-E; NKG2A; antibody-dependent cellular cytotoxicity; checkpoint inhibitor immunotherapy; multiple immunofluorescence staining; natural killer cells; tumor microenvironment

0 (NK Cell Lectin-Like Receptor Subfamily C)
0 (KLRC1 protein, human)
0 (HLA-E Antigens)
0 (Antibodies, Monoclonal)
0 (Histocompatibility Antigens Class I)

Date Created: 20240629 Date Completed: 20240808 Latest Revision: 20240809

20240812

10.1016/j.ymthe.2024.06.034

38943249