Adaptive single-KIR<sup>+</sup>NKG2C<sup>+</sup> NK cells expanded from select superdonors show potent missing-self reactivity and efficiently control HLA-mismatched acute myeloid leukemia
Alvaro Haroun-Izquierdo, Marianna Vincenti, Herman Netskar, Hanna van Ooijen, Bin Zhang, Laura E. Bendzick, Minoru Kanaya, Pouria Momayyezi, Shuo Li, Merete Thune Wiiger, Hanna Julie Hoel, Silje Zandstra Krokeide, Veronika Kremer, Geir E. Tjønnfjord, Stéphanie Berggren, Kristina Wikström, Pontus Blomberg, Evren Alici, Martin Felices, Björn Önfelt, Petter Höglund, Bahram Valamehr, Hans‐Gustaf Ljunggren, Andreas T. Björklund, Quirin Hammer, Lise Kveberg, Frank Cichocki, Jeffrey S. Miller, Karl‐Johan Malmberg, Ebba Sohlberg
Abstract
Background Natural killer (NK) cells hold great promise as a source for allogeneic cell therapy against hematological malignancies, including acute myeloid leukemia (AML). Current treatments are hampered by variability in NK cell subset responses, a limitation which could be circumvented by specific expansion of highly potent single killer immunoglobulin-like receptor (KIR) + NKG2C + adaptive NK cells to maximize missing-self reactivity. Methods We developed a GMP-compliant protocol to expand adaptive NK cells from cryopreserved cells derived from select third-party superdonors, that is, donors harboring large adaptive NK cell subsets with desired KIR specificities at baseline. We studied the adaptive state of the cell product (ADAPT-NK) by flow cytometry and mass cytometry as well as cellular indexing of transcriptomes and epitopes by sequencing (CITE-Seq). We investigated the functional responses of ADAPT-NK cells against a wide range of tumor target cell lines and primary AML samples using flow cytometry and IncuCyte as well as in a mouse model of AML. Results ADAPT-NK cells were >90% pure with a homogeneous expression of a single self-HLA specific KIR and expanded a median of 470-fold. The ADAPT-NK cells largely retained their adaptive transcriptional signature with activation of effector programs without signs of exhaustion. ADAPT-NK cells showed high degranulation capacity and efficient killing of HLA-C/KIR mismatched tumor cell lines as well as primary leukemic blasts from AML patients. Finally, the expanded adaptive NK cells had preserved robust antibody-dependent cellular cytotoxicity potential and combination of ADAPT-NK cells with an anti-CD16/IL-15/anti-CD33 tri-specific engager led to near-complete killing of resistant CD45 dim blast subtypes. Conclusions These preclinical data demonstrate the feasibility of off-the-shelf therapy with a non-engineered, yet highly specific, NK cell population with full missing-self recognition capability.