[Study of the inhibiting effect of anti-NKG2D polyclonal antibody on cytotoxicities of NK and LAK cells].

Aim: To investigate the effect of anti NKG2D polyclonal antibody(pAb) on cytotoxicities of NK and LAK cells.

Methods: Peripheral blood mononuclear cells(PBMCs) were separated by centrifugation on Ficoll-Hypaque gradients. LAK cells were induced from PBMCs by PHA (10 mg/L) and rhIL-2 (1x10(6)U/L). Then NK cells were sorted by flow cytometry(FCM). The cytotoxicities of NK and LAK cells were analyzed by MTT colorimetry after NKG2D molecule on NK and LAK cells were blocked with anti-NKG2D pAb.

Results: FCM analysis proved that both purity and activity of obtained NK cells were high.The anti-NKG2D pAb could inhibit significantly cytotoxicities of NK and LAK cells to K562 and HepG2 cells, for NK cells,having decreased 82.9% and 75.6%, for LAK cells,having decreased 52.8% and 50.2%, respectively.The anti-NKG2D pAb had no effect on cytotoxicities of NK and LAK cells to CNE cells.

Conclusion: The anti-NKG2D pAb can inhibit cytotoxocities on tumor cells by NK and LAK cells through NKG2D molecule on two effector cells.