NK/LAK细胞对人口腔癌耐细胞药株杀伤活性的观察

目的明确免疫活性细胞对肿瘤细胞的杀伤活性是否与肿瘤的耐药性相关。方法采用连续形态学观察及MTT比色法,研究淋巴因子激活的杀伤(LAK)细胞及自然杀伤(NK)细胞,对人口腔癌耐药细胞株KBV200耐药性逆转前后及亲本敏感株KB的杀伤活性。(1)在肿瘤细胞与LAK细胞共育后3 h内连续在倒置显微镜下观察LAK细胞对上述3者的杀瘤效应;(2)采用MTT比色法检测NK及LAK对3株细胞的杀伤率。结果与KB细胞组相比,在KBV200和KBV200 维拉帕米组,LAK细胞出现在靶细胞周围的时间早、数量多,伸出伪足的LAK细胞比率高,出现集落样细胞团块时间亦早。NK、LAK细胞对KBV200细胞株耐药性逆转前后的杀伤率均明显高于敏感株KB(P<0.05),而对耐药株耐药性逆转前后的杀伤率无统计学差异(P>0.05);LAK对各株的杀伤活力均明显强于NK细胞(P<0.05)。结论免疫活性细胞对KBV200细胞株有较强的杀伤作用,逆转耐药性不降低免疫活性细胞杀伤活力,提示细胞过继免疫治疗可能成为控制化疗耐药病人病情发展的一个有效手段。

Morpholoical observation on NK/LAK cell-mediated lysis of human oral carcimoma cells

Objective To understand the relation between cytotoxic activity of immunologic effector cells and multidrug resis-tance of the tumor cells. Methods Continuous observation of the morphological changes and MTT colorimetry were em-ployed to evaluate the cytotoxic activity of lymphokine-activated killer (LAK) cells and natural killer (NK) cells against mul-tidrug-resistant (MDR) human oral carcinoma cell line-KBV200 (before and after reversal of MDR) and parental drug-sensi-tive cell line KB. The morphologic changes of LAK cells and the 3 target cell lines were observed continuously under inverted microscope 3 h after co-culture of LAK cells with one of three target cell lines respectively. The lysis rates of three tumor cell lines in response to co-culture with LAK or NK cells were determined using MTT colorimetry. Results In comparison with the parental drug-sensitive cell line KB, both KBV200 and its reserved cell line by verapamil (KBVV) showed earlier adher-ence and greater number of cells lysed by LAK. In MTT colorimetry assay, the cytotoxicity of both LAK and NK cells against the 3 cell lines was associated with the effector-to-target (E/T) cell ratio; the lysis rates of KBV200 and reversed KBV200 cells by verapamil in response to LAK and NK cells were higher than that of KB cells (P<0.05), but KBV200 and KBVV did not significantly differ (P>0.05). At the same E/T ratio, LAK cells possessed stronger cytotoxicity than NK cells against all the tumor cell lines (P<0.05). Conclusions Immunologic effector cells possess strong cytotoxic activity against mutidrug-resistant cell line KBV200. Modulation of MDR does not decrease the cytotoxic activity of the immunologic effector cells. The results of this study suggest that adoptive cell immunotherapy with immunologic effector cells may be of value in controlling the progress of MDR tumors.