Quantitative Evaluation of Ultrasound-Mediated Cellular Uptake of a Fluorescent Model Drug
- PDF / 1,031,072 Bytes
- 11 Pages / 594.312 x 792 pts Page_size
- 107 Downloads / 166 Views
RESEARCH ARTICLE
Quantitative Evaluation of Ultrasound-Mediated Cellular Uptake of a Fluorescent Model Drug Matthieu Lepetit-Coiffé,1,3 Anna Yudina,1 Christel Poujol,2 Philippe Lourenco de Oliveira,1 Franck Couillaud,1 Chrit T. W. Moonen1 1
Laboratoire IMF UMR 5231 CNRS, Université Bordeaux 2, Bordeaux, France Bordeaux Imaging Center, Université Bordeaux 2, Bordeaux, France 3 Laboratoire RMSB, UMR 5536 CNRS, Université Bordeaux 2, 146 rue Léo Saignat, Case 93, 33076 Bordeaux Cedex, France 2
Abstract Purpose: This study aims to quantitatively analyze cellular uptake following local ultrasound (US)-mediated cell permeabilization. Procedures: A 2 μM cell-impermeable dye Sytox Green was co-injected with 3×107 microbubbles in the presence of C6 rat glioblastoma cell monolayer in total volume of 10 ml. A 5.8-mm diameter mono-element US transducer was positioned at a distance of 8 mm to the Opticell® membrane. Acoustical pressure of pulsed US was varied from 0.62 MPa peak-to-peak (p-p) to 1.25 MPa p-p. Large field of view (FOV015×15 mm) 22×22 mosaic acquisitions were done under epifluorescence Leica DMR microscope and analyzed in Metamorph software to evaluate cell density as well as model drug uptake percentage. Results: The size of acoustical field of the transducer closely matches the spatial pattern of the model drug internalized into the cells by US. Maximum of uptake percentage (42±15 %) was found at 0.88 MPa p-p. Conclusions: Spatial aspect of US-mediated model drug uptake has been quantitatively evaluated on adherent cells using robust 2D-mapping approach. Key words: 2D uptake maps, Fluorescent model drug, US cavitation, Epifluorescence microscopy, Macroscopy, Adherent cells, US-mediated drug delivery
Introduction
E
xternally triggered intracellular drug delivery is intended to locally enhance cell permeability to otherwise impermeable or weakly permeable compounds on demand. It is of a particular interest to the field of gene and siRNA delivery due to hydrophilicity of nucleic acids and in the field of chemotherapy delivery due to the dose-limiting toxicity of the conventional approaches. A number of biological [1], chemical [2], and physical methods of intracellular drug delivery are currently under
Correspondence to: Matthieu Lepetit-Coiffé; e-mail: [email protected]
evaluation, for example, plasma and electroporation [3, 4]. However, the latter are well adapted to subcutaneous tumor delivery but lack the penetration for deep targets [5]. On the other hand, focused ultrasound (US) permits the delivery of drug to a tumor located deep inside the body if the distance between the skin and the target is close to the focal distance of the US transducer [6]. This method is non-invasive and has already a number of approved clinical applications [7, 8] with more being in clinical trials [9–11]. In vitro evaluations of sonoporation delivery combining ultrasound and microbubbles to generate cavitational effect were performed leading to the best results at the acoustical pressure of 0.88 MPa [12, 13]. In vivo eval
Data Loading...
