RESUMEN
Since restenosis after angioplasty still remains a major clinical problems, inhibition of neointimal formation is an important subject. In this study, we focused on the transcription factor, E2F, that plays a pivotal role in the transactivation of cell-cycle regulatory genes, and also we developed a newly delivery system of decoy oligodeoxynucleotides (ODN). We transfected E2F decoy ODN mixed with an echo-contrast microbubble agent (Optison) into rat carotid artery balloon-injured model by using therapeutic ultrasound (US) to inhibit neointimal formation. Two weeks after transfection, the intimal to medial area ratio in E2F decoy+Optison+US group was significantly decreased (P < 0.01). Inhibition of cell growth was also confirmed by PCNA staining. No apparent toxicity such as inflammation could be detected in blood vessels transfected with E2F decoy ODN with Optison and ultrasound. Overall, the present studies demonstrated a novel non-viral ODN transfer method into blood vessels. A novel therapeutic strategy using E2F decoy ODN with Optison using ultrasound may be useful to inhibit restenosis in clinical practice without a viral vector.
Asunto(s)
Angioplastia Coronaria con Balón/efectos adversos , Proteínas de Ciclo Celular , Reestenosis Coronaria/etiología , Reestenosis Coronaria/terapia , Proteínas de Unión al ADN , Terapia Genética/métodos , Microburbujas , Oligodesoxirribonucleótidos/uso terapéutico , Factores de Transcripción/metabolismo , Terapia por Ultrasonido/métodos , Animales , Arterias Carótidas/patología , Reestenosis Coronaria/genética , Reestenosis Coronaria/patología , Factores de Transcripción E2F , Estudios de Factibilidad , Masculino , Oligodesoxirribonucleótidos/administración & dosificación , Ratas , Ratas Sprague-Dawley , Factores de Transcripción/genética , Transfección/métodos , Resultado del TratamientoRESUMEN
BACKGROUND: Although viral vector systems are efficient to transfect foreign genes into blood vessels, safety issues remain in relation to human gene therapy. In this study, we examined the feasibility of a novel nonviral vector system by using high-frequency, low-intensity ultrasound irradiation for transfection into blood vessels. METHODS AND RESULTS: Luciferase plasmid mixed with or without echo contrast microbubble (Optison) was transfected into cultured human vascular smooth muscle cells (VSMC) and endothelial cells (EC) with the use of ultrasound. Interestingly, luciferase activity was markedly increased in both cell types treated with Optison. We then transfected luciferase plasmid mixed with Optison by means of therapeutic ultrasound into rat artery. Two days after transfection, luciferase activity was significantly higher in carotid artery transfected with luciferase gene with Optison and ultrasound than with plasmid alone. In addition, we transfected an anti-oncogene (p53) plasmid into carotid artery after balloon injury as a model of gene therapy for restenosis. Two weeks after transfection, the intimal-to-medial area ratio in rats transfected with wild-type p53 plasmid complexed with Optison by means of ultrasound was significantly decreased as compared with control, accompanied by a significant increase in p53 protein. No apparent toxicity such as inflammation could be detected in blood vessels transfected with plasmid DNA with ultrasound and Optison. CONCLUSIONS: Overall, we demonstrated that an ultrasound transfection method with Optison enhanced transfection efficiency of naked plasmid DNA into blood vessels without any apparent toxicity. Transfection of p53 plasmid with the use of this method should be useful for safe clinical gene therapy without a viral vector system.
