Azuma A, Niitani H
Department of Pulmonary Disease, Nippon Medical School.
Nihon Kyobu Shikkan Gakkai Zasshi. 1991 Sep;29(9):1132-7.
In order to enhance cytolytic activity of lymphokine activated killer (LAK) cells against human small cell lung cancer (SCLC), bispecific F(ab')2 was used with human LAK cells and human SCLC cell lines (i.e. N231 and H69) as targets. For the construction of bispecific F(ab')2, LU246 monoclonal antibody (mAb) recognizing the antigen expressed on the surface of both SCLC cell lines, was employed. OKT3 or 3G8 mAbs recognizing CD3 on T cell and CD16 on NK cell functional molecules respectively, were chemically cross-linked to LU246 mAb using 5,5'-dithio-bis 2-nitrobenzoic acid (DTNB). Bispecific F(ab')2 adding to LAK cells increased the conjugation with target cells. The phenotypes of LAK cells change at their various culture times. Although cytolytic activity of LAK cells gradually decreases after one week of culture time, the enhanced cytotoxicity of LAK cell using bispecific F(ab')2 has been kept even after long culture. Furthermore, target cell lysis enhanced by bispecific F(ab')2 has been greater than that by classical ADCC using LU246 mAb. These bispecific antibodies should be effective reagents for adoptive immunotherapy in human SCLC patients.
为增强淋巴因子激活的杀伤（LAK）细胞对人小细胞肺癌（SCLC）的细胞溶解活性，将双特异性F(ab')2与人LAK细胞以及人SCLC细胞系（即N231和H69）作为靶标一起使用。为构建双特异性F(ab')2，采用了识别两种SCLC细胞系表面表达抗原的LU246单克隆抗体（mAb）。分别识别T细胞上CD3和NK细胞功能分子上CD16的OKT3或3G8 mAb，使用5,5'-二硫代双（2-硝基苯甲酸）（DTNB）与LU246 mAb进行化学交联。向LAK细胞中添加双特异性F(ab')2增加了与靶细胞的结合。LAK细胞的表型在其不同培养时间会发生变化。尽管LAK细胞的细胞溶解活性在培养一周后逐渐降低，但使用双特异性F(ab')2增强的LAK细胞细胞毒性即使在长时间培养后仍得以保持。此外，双特异性F(ab')2增强的靶细胞裂解作用大于使用LU246 mAb的经典抗体依赖的细胞介导的细胞毒性（ADCC）。这些双特异性抗体应是用于人SCLC患者过继性免疫治疗的有效试剂。
