Intracellular antibody delivery into live cells has significant implications for research and therapeutic applications. However, many delivery systems lack potency due to low uptake and/or endosomal entrapment and understanding of intracellular delivery processes is lacking. Herein, we studied the cellular uptake, intracellular trafficking and targeting of antibodies using our previously developed Hex antibody nanocarrier. We demonstrated Hex-antibodies were internalized through multiple endocytic routes into lysosomes and provide evidence of endo/lysosomal disruption and Hex-antibody release to the cytosol. Cytosolic antibodies retained their bioactivity for at least 24 h. Functional effect of Hex delivered anti-STAT3 antibodies was evidenced by inhibition of nuclear translocation of cytosolic transcription factor STAT3. This study has generated understanding of key steps in the Hex intracellular antibody delivery system and will facilitate the development of effective cytosolic antibody delivery and applications in both the therapeutic and research domains.

将细胞内抗体递送到活细胞中对研究和治疗应用具有重要意义。然而，许多递送系统由于低摄取和/或内体包埋而缺乏效力，并且缺乏对细胞内递送过程的理解。在这里，我们使用我们之前开发的 Hex 抗体纳米载体研究了抗体的细胞摄取、细胞内运输和靶向。我们证明了 Hex 抗体通过多种内吞途径内化到溶酶体中，并提供了内/溶酶体破坏和 Hex 抗体释放到胞质溶胶的证据。胞质抗体保持其生物活性至少 24 小时。Hex 传递的抗 STAT3 抗体的功能效应通过抑制细胞溶质转录因子 STAT3 的核转位得到证实。