肝癌患者外周血自然杀伤细胞的功能分析

Characteristics of peripheral NK cells in hepatocellular carcinomar patients

目的探讨肝癌患者外周血自然杀伤（NK）细胞的数目和功能，以进一步了解肝癌的发病机制。方法入选35例肝癌患者和24名健康人，用流式细胞仪检测外周血NK细胞亚群频率；通过检测NK细胞分泌干扰素（IFN）γ的能力和杀伤K562细胞的能力，评价NK细胞的功能。数据用均数±标准差（i±s）表示，不同组间的比较采用SPSS13．0进行Mann—Whitney非参数检验分析。结果与健康对照组相比，肝癌患者外周血NK细胞的频率明显降低（12．19％±10．85％与24．01％±8．78％，u=4．01，P〈0．01）；其中CD56^bright CD16^neg NK细胞频率增加（0．62％±0．39％与0．48％±0．28％，u=1．96，P〈0．05），而CD56^dim CD16^pos NK细胞频率明显降低（11．59％±7．49％与22．66％±8．84％，u=3．92，P〈0．01）。肝癌患者外周血NK细胞经过佛波酯刺激后分泌IFNY的能力降低（有效细胞13．31％），并且对K562细胞的杀伤活性明显降低，以30：1、10：1、1：1与K562细胞混合后，其杀伤效率在肝癌组与对照组分别为16．72％±7．33％与26．29％±12．36％（u=2．52，P〈0．05）、8．01％±4．40％与13．09％±5．03％（u=3．32，P〈0．05）、3．51％±2．82％与3．42％±1．64％（U=1．56，P〉0．05）。结论肝癌患者体内NK细胞功能受损，抗肿瘤能力下降，这可能是肝癌患者抗肿瘤免疫应答缺陷的机制之一。

Objective Functional defects in NK cells have been proposed to be responsible for the impairment of anti-tumor immune responses. However, it remained unclear whether the function of NK cells were impaired in patients with hepatocellular carcinoma. To address this issue, we analyzed the frequency and function of peripheral NK cell subsets in hepatocellular carcinomar （HCC） patients. Methods 35 HCC patients and 24 healthy controls （HC） were enrolled in the study. Peripheral NK frequency was analyzed using flow cytometry. In addition, the capacity of NK ceils to produce IFN γ, and to lyse K562 cells was evaluated. Results In contrast with the healthy controls, the frequency of peripheral NK cells in hepatocellular carcinomar patients was decreased （12.19% ± 10.85% vs 24.01% ± 8.78%, u = 4.01, P 〈 0.01）, while the frequency of CD56^bright CD16^neg NK cells was increased （0.62% ± 0.39% vs 0.48% ± 0.28%, u = 1.96, P 〈 0.05）, and the frequency of CD56^dim CD16^pos NK cells was significantly decreased （11.59% ± 7.49% vs 22.66% ± 8.84%, u = 3.92, P 〈 0.01）. In addition, peripheral NK cells from HCC patients exhibited decreased capacity to produce IFN γ （effective cells 13.31%） and to lyse K562 cells （mixed ratio 30：1, 10：1, 1：1, effective cells 16.72% ± 7.33% vs 26.29% ± 12.36%, u = 2.52, P 〈 0.05, 8.01% ± 4.40% vs 13.09% ± 5.03%, u = 3.32, P 〈 0.05, 3.51% ± 2.82% vs 3.42% ± 1.64%, u = 1.56, P 〉 0.05, respectively） as compared with healthy subjects. Conclusions Anti-tumor activity of NK cells in HCC patients was impaired.