CD33 (Siglec-3) Inhibitory Function: Role in the NKG2D/DAP10 Activating Pathway

Figure 1

Functional differences of NKL cells cultured at different growing conditions. Cytotoxic ability against (a) 721.221 or (b) K562 target cells displayed by 24 h (■) or 3 weeks (◊) exponentially growing NKL cells, as described in Materials and Methods. One representative experiment out of three with similar results is shown. (c) Redirected cytotoxicity against P815 cells in the presence of mAb against CD16, NKp46, NKG2D, or 2B4 activating receptors by NKL cells (3 : 1 E/T ratio) grown at an exponential phase for 24 h, 1 week, or 3 weeks. According to these data, the 24-48 h exponentially growing NKL cells were referred as high-cytotoxicity NKL cells (hc-NKL). Data show the of P815 lysis percentages of a minimum of three independent experiments. All differences are statistically significant. The highest cytotoxic ability was displayed by 24 h exponentially growing NKL cells. .

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