IL-15 superagonist N-803 improves IFNγ production and killing of leukemia and ovarian cancer cells by CD34+ progenitor-derived NK cells

Abstract

Allogeneic natural killer (NK) cell transfer is a potential immunotherapy to eliminate and control cancer. A promising source are CD34 + hematopoietic progenitor cells (HPCs), since large numbers of cytotoxic NK cells can be generated. Effective boosting of NK cell function can be achieved by interleukin (IL)-15. However, its in vivo half-life is short and potent trans-presentation by IL-15 receptor α (IL-15Rα) is absent. Therefore, ImmunityBio developed IL-15 superagonist N-803, which combines IL-15 with an activating mutation, an IL-15Rα sushi domain for trans-presentation, and IgG1-Fc for increased half-life. Here, we investigated whether and how N-803 improves HPC-NK cell functionality in leukemia and ovarian cancer (OC) models in vitro and in vivo in OC-bearing immunodeficient mice. We used flow cytometry-based assays, enzyme-linked immunosorbent assay, microscopy-based serial killing assays, and bioluminescence imaging, for in vitro and in vivo experiments. N-803 increased HPC-NK cell proliferation and interferon (IFN)γ production. On leukemia cells, co-culture with HPC-NK cells and N-803 increased ICAM-1 expression. Furthermore, N-803 improved HPC-NK cell-mediated (serial) leukemia killing. Treating OC spheroids with HPC-NK cells and N-803 increased IFNγ-induced CXCL10 secretion, and target killing after prolonged exposure. In immunodeficient mice bearing human OC, N-803 supported HPC-NK cell persistence in combination with total human immunoglobulins to prevent Fc-mediated HPC-NK cell depletion. Moreover, this combination treatment decreased tumor growth. In conclusion, N-803 is a promising IL-15-based compound that boosts HPC-NK cell expansion and functionality in vitro and in vivo. Adding N-803 to HPC-NK cell therapy could improve cancer immunotherapy.

CD34 + progenitor-derived NK cell and gemcitabine combination therapy increases killing of ovarian cancer cells in NOD/SCID/IL2Rg null mice

“…Another explanation might be that our HPC-NK cells are already highly activated in the presence of OC cells without gemcitabine treatment (Figure 4). 6,16,[24][25][26][27][28] In previous publications, we have shown that we can already approach nearly 100% HPC-NK cell-mediated OC cell death in the absence of gemcitabine using an E:T ratio of 10:1, which is lower compared to the E:T ratio that is needed for peripheral blood (PB)-NK cells to kill 100% of OC cells. 6,16 However, to study possible additive effects of HPC-NK cells and gemcitabine in a more physiological setting, all combination experiments were performed at low E:T ratios.…”

“…CD34 + HPCs were expanded and differentiated into HPC-NK cells within 5-6 weeks as described previously. 16 HPC-NK cells (>70% CD56 + ) were used directly after culture or after cryopreservation and 5-8-day re-culture. HPC-NK cells were cultured in Iscove's Modified Dulbecco's Medium (IMDM, Gibco, 21980-032) supplemented with 10% fetal calf serum (FCS, Corning, 35-079-CV or Integro, 5-45900) (IMDM10; HPC-NK cell functional assay) or Roswell Park Memorial Institute 1640 medium (RPMI, Gibco, 21875-034) with 10% FCS (RPMI10; phenotyping and killing assay).…”

Natural Killer Cells and Type 1 Innate Lymphoid Cells in Hepatocellular Carcinoma: Current Knowledge and Future Perspectives

“…Other approaches consist of coupling IL-15 to the sushi domain of the IL-15Rα that is fused to and IgG-Fc fragment antibodies to increase its stability. The IL-15 supplementation to NK cells using this molecule, ALT-803, demonstrated improved anti-tumor outcomes in preclinical models [284][285][286][287][288] and phase I clinical trials [289]. Given these promising results, such treatments are currently being tested in HCC, aiming to reverse NK cell dysfunction and enhance patient outcomes (Table 3).…”

Specific Features of Ovarian Cancer Metastasis

“…С худшим прогнозом при РЯ коррелирует накопление CD33 + миелоидных супрессорных клеток в БС (под влиянием VEGF), которое ведет к неспособности накапливать CD8 + клетки [49]. Злокачественные новообразования чувствительны к иммунитету, опосредованному натуральными киллерами (NK) [50]. В экспериментах in vivo на модели ксенотрансплантата мыши показана эффективность высокоактивных NK, полученных из человеческих CD34 + гемопоэтических стволовых и прогениторных клеток, в инфильтрации и опосредованном уничтожении сфероидов РЯ [51].…”

“…Большое количество цитостатических NK может быть получено из различных источников, включая пуповинную кровь. Терапия при помощи NK является перспективной стратегией в лечении рака, так как позволяет избирательно воздействовать на раковые клетки без нанесения вреда здоровым тканям [50]. Данные механизмы активно изучаются.…”