Fig. 3
Characterization of HALipid-NK cells. A Schematic representation of NK cell coating with HA-PEG-Lipid and fabricated HALipid-NK cells. First, 1 × 106 NK cells were coated with 200 μL of Fluor-HA-PEG-Lipid coating solution (1 mg/mL) at RT for 30 min. After washing, Fluor-HALipid-NK cells were visualized via fluorescence microscope. B Fluorescence images of HADM-NK cell, HADS-NK cell, and HACH-NK cell. Obtained images were analyzed with ImageJ. C Quantitative assessment of NK cell coating performance of HALipid-NK cells. (*) indicates a significant difference compared to HADM-NK cells (p < 0.05). D Retention of cell membrane anchoring of Fluor-HA-PEG-Lipid detected by flow cytometry at 0, 15, 30, 45, and 60 min. The relative mean fluorescence intensity (MFI) was assessed based on the MFI value at 0 min. (*) indicates a significant difference compared to 0 h for each group (p < 0.05). (#) indicates a significant difference compared to HADS-NK cells at the same time point (p < 0.05). ($) indicates a significant difference compared to HADM-NK cells at the same time point (p < 0.05). E Illustration depicting the average amount of HA-PEG-Lipid removal from NK cells after 60 min