目的 :从人外周血中分离纯化高浓度、高纯度及活性良好的静息状态NK细胞 ,为进一步研究其特性打下基础。方法 :应用Percoll非连续密度梯度离心法结合panning负分离法获得所需NK细胞 ,并用免疫组化Envision二步法、MTT还原法分别对NK细胞的纯度、酶活性及细胞毒活性进行全面鉴定。结果 :NK细胞纯度为 6 0～ 80 % ,浓度最低可达 10 6/ml,细胞酶活性良好 ,细胞毒活性平均达 5 0 %。结论 :此分离法所获NK细胞数量及纯度较高 ,不影响细胞的酶活性 ,也不会激活NK细胞 ,是一种良好的静息状态NK细胞的分离方法。 OBJECTIVE: To isolate and purify natural killer (NK) cells in high concentration, high purity and good activity from human peripheral blood, and lay the foundation for further study of its characteristics. Methods: The required NK cells were obtained by Percoll discontinuous density gradient centrifugation and panning negative separation. The purity, enzyme activity and cytotoxic activity of NK cells were identified by immunohistochemical Envision two-step method and MTT reduction method respectively. Results: The purity of NK cells was 60% ~ 80% and the lowest concentration was 10 6 / ml. The activity of NK cells was good and the average cytotoxic activity was 50%. Conclusion: The number of NK cells obtained by this separation method and the purity of higher, does not affect cell enzyme activity, it will not activate NK cells, is a good resting state of NK cells.