doi:10.1038/s41598-024-62968-2engFelgueres, María-JoséEsteso, GloriaGarcía-Jiménez, Álvaro F.Dopazo, AnaAguiló, NachoMestre-Durán, CarmenMartínez-Piñeiro, LuisPérez-Martínez, AntonioReyburn, Hugh T.Valés-Gómez, MarBCG priming followed by a novel interleukin combination activates Natural Killer cells to selectively proliferate and become anti-tumour long-lived effectorsART-2024-138843The short-lived nature and heterogeneity of Natural Killer (NK) cells limit the development of NK cell-based therapies, despite their proven safety and efficacy against cancer. Here, we describe the biological basis, detailed phenotype and function of long-lived anti-tumour human NK cells (CD56highCD16+), obtained without cell sorting or feeder cells, after priming of peripheral blood cells with Bacillus Calmette-Guérin (BCG). Further, we demonstrate that survival doses of a cytokine combination, excluding IL18, administered just weekly to BCG-primed NK cells avoids innate lymphocyte exhaustion and leads to specific long-term proliferation of innate cells that exert potent cytotoxic function against a broad range of solid tumours, mainly through NKG2D. Strikingly, a NKG2C+CD57-FcεRIγ+ NK cell population expands after BCG and cytokine stimulation, independently of HCMV serology. This strategy was exploited to rescue anti-tumour NK cells even from the suppressor environment of cancer patients’ bone marrow, demonstrating that BCG confers durable anti-tumour features to NK cells.2024http://zaguan.unizar.es/record/13582810.1038/s41598-024-62968-2http://zaguan.unizar.es/record/135828oai:zaguan.unizar.es:135828info:eu-repo/grantAgreement/ES/AEI/PID2020-115506RB-I00info:eu-repo/grantAgreement/ES/MCINN/PID2021-123795OB-I00Scientific reports (Nature Publishing Group) 14, 1 (2024), 16 pp.byhttps://creativecommons.org/licenses/by/4.0/deed.esinfo:eu-repo/semantics/openAccess