Research Paper Volume 17, Issue 3 pp 798—821

Figure 6. Older individual-derived OCs induced lower levels of activation in NK cells. Osteoclasts (OCs) were generated as described in the Materials and Methods section. NK cells and OCs co-culture was performed as described in Figures 2, 5. NK cell-mediated cytotoxicity against OSCSCs was determined on days 9 and 15 using a standard 4-hour ⁵¹Cr release assay. The lytic units 30/10⁶ cells were determined using the inverse number of NK cells required to lyse 30% of OSCSCs x 100 (A). Lytic units per 1 % NK cells were determined based on the percentages of CD16+CD56+ NK cells in the cultures obtained by flow cytometric analysis (B). The supernatants were harvested from the cultures on days 6, 9, 12, 15, 18, 21, and 25 to determine IFN-γ secretion using single ELISA (C), and the levels IFN-γ pg/ml were adjusted based on per million of cells (D). ****(p-value <0.0001), ***(p-value 0.0001-0.001).