Fig. 1. Generation of mACE2-CAR_sIL15 NK cells.

a Design of the mACE2-CAR and sIL15 retroviral vectors. The mACE2-CAR vector contains a mutant human ACE2, a human IgG1-hinge region, and the CD28 transmembrane region, followed by the intracellular domains of CD28 and CD3ζ linked to a T2A and a truncated (t) LNGFR (i). The sIL15 vector contains an IL-2 signaling peptide, a codon-optimized IL-15, and the GM-CSF receptor (CSF2R) signaling peptide, followed by a truncated (t) EGFR (ii). b Generation of mACE2-CAR_sIL15 NK cells. The pictures were created with BioRender.com. c The transduction efficiency of control tEGFR or sIL15 NK cells and mACE2-CAR_sIL15 NK cells was determined by flow cytometry. Control tEGFR or sIL15 NK cells expressed the tEGFR marker, while mACE2-CAR_sIL15 NK cells expressed the tLNGFR maker (representing mACE2-CAR expression) as well as the tEGFR marker (representing sIL15 expression). d The phenotypic analysis of mACE2-CAR_sIL15 NK cells and control tEGFR or sIL15 NK cells were determined by flow cytometry. Representative flow cytometry histograms and summary data from three different donors are shown. P values were determined by one-way ANOVA with multiple comparisons and adjusted by the Holm-Sidak method. Data are presented as mean ± SD. For mACE2-CAR_sIL15 NK cells, sIL15 expression is denoted as LNGFR^–EGFR⁺, mACE2-CAR expression is denoted as LNGFR⁺EGFR^–, and sIL15 & mACE2-CAR_co-expression is denoted as LNGFR⁺EGFR⁺. Source data are provided as a Source Data file.