15353-j-veluchamy

3 HLA independent killing of cervical tumors by UCB-NK cells | 79 Figure 3: NK-activating receptors in PBNK and UCB-NK and their ligand expression in cervical cancer cell lines influencing NK cytotoxicity (a) Percentage of positive cells within the NK cell population for NK activating receptors DNAM-1 and NKG2D for PBNK only, PBNK stimulated with cytokines (IL-2+IL-15) and UCB-NK only were determined by flow cytometry. The data presented is from three representative donors for PBNK and UCB-NK. PBNK only are denoted by open circles, PBNK (IL-2+IL-15) are denoted by closed circles and UCB-NK only by closed squares. (b) Representative example of histograms showing geometric mean fluorescence intensity (MFI) for NK activating ligands PVR (ligand of DNAM-1 receptor), MICA/B, and ULBP1, -3 and -2/5/6 (ligands of NKG2D receptor). (c) PBNK and UCB-NK were coated with NKG2D and/or DNAM- 1 blocking antibodies and incubated with C33A and SiHa cells. Cytotoxicity levels (∆7AAD) were measured from 7AAD + C33A and SiHa cells at the end of a 4h assay. Data presented are means of triplicate values from three different PBNK and three different UCB-NK donors; Bars represent mean ± SEM. * P <0.05 and ** P < 0.01 calculated with paired, two-way ANOVA multiple comparisons of column means.