导向治疗的效果依赖于其载体导向性强弱和“弹头”的杀伤能力大小。最初使用的单克隆抗体载体,目前已发展至瓶颈阶段,临床未能取得明显稳定可靠的疗效[1,2]。于是人们纷纷转向以下几个方面:(1)改进单克隆抗体性能,如用改形抗体、嵌合抗体、单域抗体和基因工程抗体等以减少异源 The effectiveness of targeted therapy depends on the strength of its vector-driven and “bullet” killing capacity. The initial use of monoclonal antibody carrier, has now developed to the bottleneck stage, clinically failed to achieve significant stable and reliable effect [1,2]. So people turn to the following aspects: (1) to improve the performance of monoclonal antibodies, such as the use of modified antibodies, chimeric antibodies, single domain antibodies and genetically engineered antibodies to reduce heterologous