血清抗体及补体对利妥昔单抗介导的NK 细胞杀伤Raji细胞作用的影响

 【摘要】 目的 体外检测血清抗体及补体对利妥昔单抗介导的NK细胞对Raji细胞杀伤作用的影响。方法 通过巢式反转录聚合酶链反应（nest-PCR）检测NK细胞上FcγRⅢa（CD16a）基因型；流式细胞术检测加入血清抗体前后NK细胞上FcγRⅢa的表达；DIO-PI双荧光染色法检测添加血清补体及抗体后NK细胞对Raji细胞的杀伤效应强度。结果 添加血清补体组杀伤率较未添加组明显增强，而添加血清抗体组杀伤率较未添加组明显减弱，在FcγRⅢa-158V／V组内，添加血清补体组、添加血清抗体组与未添加组细胞毒性指数分别为（94.25±1.79） %、（59.79±0.66） %和（69.05±2.38） %，三组之间两两比较均P＜0.05；在FcγRⅢa-158V／F组内，添加血清补体组、添加血清抗体组与未添加组细胞毒性指数分别为（66.71±5.57） %、（18.13±2.99） %和（39.63±3.86） %，三组之间两两比较均P＜0.05。结论 血清补体可增强利妥昔单抗介导的NK细胞对Raji细胞的杀伤作用。血清抗体会减弱利妥昔单抗介导的NK细胞对Raji细胞的杀伤作用。使用肿瘤特异性单克隆抗体（MAb）治疗肿瘤患者时，同时输注新鲜冷冻血浆可提高其抗肿瘤疗效；而MAb与静脉注射用免疫球收白（IVIG）同时使用则可能降低其抗肿瘤疗效。

Influence of serum complement and IgG on rituximab-dependent NK cell-mediated cytotoxicity to Raji cells

Objective To determine the influence of serum complement and lgG on rituximab- dependent NK cell-mediated cytotoxicity to Raji cells in vitro. Methods FcγRⅢa a （CD1oa） polymorph：sm of NK cells were detected by nest-PCR. Effects of serum IgG on FcγRⅢa expression of NK cells in vitro were analyzed by flow cytometry. The target cells（Raji cells） were stained with DIO, cultured with effector cells（NK cells） and rituximab with or without serum IgG/ccmplement, and finally stained with propidium iodide （PI）,then these cells were tested by flow cytometry and the cytotoxic index was calculated as well. Results The cytotoxic indexes of the ADCC ＋CDC groups were higher than those of ADCC groups, but the serura IgG groups were lower than the ADCC groups. In FcγRⅢa-158V/V groups, the eytotoxie indexs of the ADCC＋CDC groups, the serum IgG groups and the ADCC groups were （94.25±1.79） %,（59.79±0.66） % and（69.05± 2.38） %, respectively ,and the differences among the groups were statistically significant （P〈 0.05）. In FcγRⅢa- 158V/F groups, the eytotoxie indexs of these threse groups were （66.71±5.57） %,（18.13±2.99） % and （39.63± 3.86） %, respectively, and the differences among the groups were also statistically significant （P〈 0.05）. Conclusions Complement may enhance the rituximab-mediated NK cell eytotoxieity to Raii cells, whereas, serum IgG may weaken the cytotoxicity against Raji cells. It is clued up that for patients treated by tumorspecific monolonal antibody （MAb）, combined infusion of fresh frozen plasma could promote its anti-umor effect, however, MAb combined with IVIG may impair its anti-tumor effect.