Volumetric contrast-enhanced ultrasound imaging of renal perfusion.

Objectives: To determine whether volumetric contrast-enhanced ultrasound (US) imaging has the potential to monitor changes in renal perfusion after vascular injury.

Methods: Volumetric contrast-enhanced US uses a series of planar image acquisitions, capturing the nonlinear second harmonic signal from microbubble contrast agents flowing in the vasculature. Tissue perfusion parameters (peak intensity [IPK], time to peak intensity [TPK], wash-in rate [WIR], and area under the curve [AUC]) were derived from time-intensity curve data collected during in vitro flow phantom studies and in vivo animal studies of healthy and injured kidneys.

Biodistribution of P-selectin targeted microbubbles.

Purpose: To evaluate binding of P-selectin targeted microbubbles (MB) in tumor vasculature; a whole-body imaging and biodistribution study was performed in a tumor bearing mouse model.

Methods: Antibodies were radiolabeled with Tc-99 m using the HYNIC method. Tc-99 m labeled anti-P-selectin antibodies were avidin-bound to lipid-shelled, perfluorocarbon gas-filled MB and intravenously injected into mice bearing MDA-MB-231 breast tumors.

Enhancement of adenovirus delivery after ultrasound-stimulated therapy in a cancer model.

Improving the efficiency of adenovirus (Ad) delivery to target tissues has the potential to advance the translation of cancer gene therapy. Ultrasound (US)-stimulated therapy uses microbubbles (MBs) exposed to low-intensity US energy to improve localized delivery. We hypothesize that US-stimulated gene therapy can improve Ad infection in a primary prostate tumor through enhanced tumor uptake and retention of the Ad vector.

An animal model allowing controlled receptor expression for molecular ultrasound imaging.

Reported in this study is an animal model system for evaluating targeted ultrasound (US) contrast agents binding using adenoviral (Ad) vectors to modulate cellular receptor expression. An Ad vector encoding an extracellular hemagglutinin (HA) epitope tag and a green fluorescent protein (GFP) reporter was used to regulate receptor expression. A low and high receptor density (in breast cancer tumor bearing mice) was achieved by varying the Ad dose with a low plaque forming unit (PFU) on day 1 and high PFU on day 2 of experimentation.

Molecular ultrasound imaging using a targeted contrast agent for assessing early tumor response to antiangiogenic therapy.

Objectives: Contrast-enhanced ultrasound (US) and targeted microbubbles have been shown to be advantageous for angiogenesis evaluation and disease staging in cancer. This study explored molecular US imaging of a multitargeted microbubble for assessing the early tumor response to antiangiogenic therapy.

Methods: Target receptor expression of 2LMP breast cancer cells was quantified by flow cytometric analysis and characterization established with antibodies against mouse α(V)β3- integrin, P-selectin, and vascular endothelial growth factor receptor 2.