Preparation of ultrasound microbubbles crosslinked to albumin nanoparticles packaged with tissue-type plasminogen activator gene plasmid and method of in vivo transfection

Ji Jun, Ji Shang-Yi, He Xia, Ling Wen-Ping
Department of Pathology, ShenZhen Sun Yat-Sen Cardiovascular Hospital, ShenZhen, GuangDong Province, People's Republic of China

Aims: To observe the effect of constructed ultrasound microbubble crosslinked to albium nanoparticles packaged with tissue-type plasminogen activator (tPA) gene plasmid on the in vivo transfection.
Methods: The rabbits were chosen for all experiments. A highly expressive gene plasmid for tPA was constructed and packaged into a prepared nanoparticle with bovine serum albumin (BSA). This albium nanoparticle packaged with tPA gene plasmid was crosslinked to an ultrasound microbubble prepared with BSA and sucrose to form a nano-targeting vector system for tPA gene transfection. The transfection and effective expression of tPA in heart, liver, leg skeletal muscle and the cervical rib were detected with polyclonal antibodies to tPA using immunohistochemical method; the tPA level and D-dimer content of blood were also tested.
Results: The expression of tPA could be seen in the tissues mentioned above, with the increase in blood tPA level and D-dimer content from 0.20 ± 0.05 µg/L and 81.76 ± 9.84 µg/L before the operation, to the higher levels of 0.44 ± 0.05 µg/L and 669.28 ± 97.74 µg/L after transfection.
Conclusion: The nano-targeting vector system for tPA gene was contructed successfully. This provides a new theory and experimental method for the nano-targeted transgene.

Keywords: tissue-type plasminogen activator, albium nanoparticle, ultrasound microbubble, targeting transfection