Interaction of ultrasound and model membrane systems: analyses and predictions

Tata, Darayash; Dunn, F.

doi:10.1021/j100187a067

Cited by 37 publications

(36 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Gene Therapy (2000) 7, 2023-2027. component of many lipofection reagents which promotes endosomal 'breakout' following DNA internalisation. 13,14 We have previously reported that a 60 s exposure of porcine VSMC to low intensity 1 MHz ultrasound during naked plasmid transfection enhanced luciferase activity measured 48 h later by up to 10-fold. 15 Reporter gene expression following lipofection was also enhanced by two-to three-fold.…”

mentioning

confidence: 97%

Microbubble-enhanced ultrasound for vascular gene delivery

et al. 2000

View full text Add to dashboard Cite

Progress in cardiovascular gene therapy has been hampered by concerns over the safety and practicality of viral vectors and the inefficiency of current nonviral transfection techniques. We have previously reported that ultrasound exposure (USE) enhances transgene expression in vascular cells by up to 10-fold after naked DNA transfection, and enhances lipofection by up to three-fold. We report here that performing USE in the presence of microbubble echocontrast agents enhances acoustic cavitation and is associated with approximately 300-fold increments in transgene

show abstract

mentioning

confidence: 97%

Microbubble-enhanced ultrasound for vascular gene delivery

et al. 2000

View full text Add to dashboard Cite

show abstract

“…Furthermore, many lipofection reagents contain dioleoylphosphatidylethanolamine (DOPE), which encourages DNA "breakout" from endosomes through a physicochemical transition that is known to be accelerated by USE. 4,5 On the basis of these observations, we investigated the hypothesis that USE may enhance transgene expression after naked DNA and/or liposome-mediated transfection of primary vascular cells. …”

mentioning

confidence: 99%

Ultrasound Enhances Reporter Gene Expression After Transfection of Vascular Cells In Vitro

et al. 1999

View full text Add to dashboard Cite

Background-Restenosis after percutaneous coronary intervention remains a serious clinical problem. Progress in local gene therapy to prevent restenosis has been hindered by concerns over the safety and efficacy of viral vectors and the limited efficiency of nonviral techniques. This study investigates the use of adjunctive ultrasound to enhance nonviral gene delivery. Methods and Results-Cultured porcine vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) were transfected with naked or liposome-complexed luciferase reporter plasmid for 3 hours. Ultrasound exposure (USE) for 60 seconds at 1 MHz, 0.4 W/cm 2 , 30 minutes into this transfection period enhanced luciferase activity 48 hours later by 7.5-fold and 2.4-fold, respectively. Luciferase activity after lipofection of ECs was similarly enhanced 3.3-fold by adjunctive USE. USE had no effect on cell viability, although it inhibited VSMC but not EC proliferation. An alternative strategy is single-dose local administration of agents that can modify the vascular response to injury, including local gene therapy. 1 Viral vectors achieve the highest efficiency, but substantial concerns remain over their clinical safety and long-term efficacy. 1 Although relatively safe, nonviral gene delivery, including lipofection, is currently at least 10-fold less efficient. 1 Ultrasound exposure (USE) has been shown to permeabilize plasma membranes and reduce the thickness of the unstirred layer at the cell surface, 2,3 which should encourage DNA entry into cells. Furthermore, many lipofection reagents contain dioleoylphosphatidylethanolamine (DOPE), which encourages DNA "breakout" from endosomes through a physicochemical transition that is known to be accelerated by USE. 4,5 On the basis of these observations, we investigated the hypothesis that USE may enhance transgene expression after naked DNA and/or liposome-mediated transfection of primary vascular cells. Conclusions-Adjunctive Methods Cell Culture and Transfection ConditionsPorcine medial vascular smooth muscle cells (VSMCs) and lumenal endothelial cells (ECs) from the thoracic aorta of Yorkshire White cross pigs aged Ͻ6 months were cultured in DMEM containing 10% porcine serum; EC cultures were supplemented with EC growth factor (20 g/mL; Sigma) and heparin (90 g/mL; Sigma). All transfections were performed for 3 hours at 37°C in 24-well plates with cells at 60% to 70% confluence and were stopped by dilution with 1 mL of fresh culture medium. Naked DNA transfections were performed in 200 L of DMEM containing 10% porcine serum and 7.5 g/mL luciferase plasmid DNA (pGL3; Promega) per well. Lipofections used Promega Tfx-50 (which contains DOPE), according to conditions optimized for VSMCs (200 L of DMEM containing 10% porcine serum; DNA:lipid charge ratio of 4:1; 7.5 g/mL final DNA concentration) and ECs (200 L of serum-free DMEM; DNA:lipid charge ratio 3:1; 5 g/mL final DNA concentration).Thirty minutes after the transfection was begun, USE was performed for 60 seconds with a custom-built, 10-mm-diameter, 1-MHz ...

show abstract

“…These results match closely the published data. For example, Tata and Dunn (1992) obtained for the DPPC and DMPC vesicles the absorption number values,˛ /c = 0.5 and 0.41 ml/g, respectively (for multilamellar vesicles in distilled water at pH 7.4; buffer: 10 mM Hepes, 139 mM NaCl, 6 mM KCl; lipid concentration: 10 mg/ml; measurement frequency about 2 MHz, standing for the wave length and c for the lipid concentration). Taking the lipid concentrations in our experiment and using the published data we calculate the absorption coefficients to be 0.15 cm −1 for both the DMPC and DPPC vesicles.…”

Section: Measurements Of Thermal Acoustic Radiation Of Vesicles Durinmentioning

confidence: 99%

“…It is well known that lipid phase transitions in model membranes can be investigated using acoustical techniques (e.g., Tata and Dunn, 1992;Kharakoz et al, 1993) and calorimetric measurements (e.g., Sujak et al, 2007). These methods are often used in combination (e.g., Halstenberg et al, 1998;Kharakoz et al, 2007;Schrader et al, 2007).…”

Section: Introductionmentioning

confidence: 99%