Fig. 5

In vitro anticancer activity using HALipid-NK cells. A Illustration of the anticancer process involving HALipid-NK cells. HALipid-NK cells achieved physical closeness via HA and CD44 affinity, subsequently enhancing cancer recognition and initiating cancer-killing. B Cluster formation of effector NK cells and target cells (E/T cluster). CD44-overexpressing cancer cells (MDA-MB-231) and CD44-negative normal cells (hfibroblasts) were utilized as target cells to compare CD44-specific target recognition of HALipid-NK cells. NK cells were labeled with Calcein-AM (green). Target cells were labeled with CellTracker™ Red. Effector NK cells and target cells were co-cultured at 37 ºC for 30 min. E/T cluster formation was quantitatively analyzed as a population of double-positive cells in flow cytometry measurements. (*) indicates a significant difference compared to NK cell group (p < 0.05). (#) indicates a significant difference compared to HADS-NK cell group (p < 0.05). C Percentage of specific cell lysis by HALipid-NK cells. NK cells or HALipid-NK cells were co-cultured with target cells at a 10:1 effector to target (E:T) ratio at 37 ºC for 4 h. Target cell lysis was measured by a Calcein release assay. (*) indicates a significant difference compared to NK cell group (p < 0.05). (#) indicates a significant difference compared to HADS-NK cell group (p < 0.05). (n.s.) indicates no statistically significant difference between experimental groups