Molecular magnetic resonance imaging of Alpha-v-Beta-3 integrin expression in tumors with ultrasound microbubbles.

Microbubbles (MB) are used as ultrasound (US) contrast agents and can be efficiently targeted against markers of angiogenesis and inflammation. Due to their gas core, MB locally alter susceptibilities in magnetic resonance imaging (MRI), but unfortunately, the resulting contrast is low and not sufficient to generate powerful molecular MRI probes. Therefore, we investigated whether a potent molecular MR agent can be generated by encapsulating superparamagnetic iron oxide nanoparticles (SPION) in the polymeric shell of poly (n-butylcyanoacrylate) (PBCA) MB and targeted them against αβ integrins on the angiogenic vasculature of 4T1 murine breast carcinomas.

MR and PET-CT monitoring of tissue-engineered vascular grafts in the ovine carotid artery.

The modification of biomaterials to comply with clinically employed monitoring techniques is a promising strategy to support clinical translation in regenerative medicine. Here, multimodal imaging of tissue-engineered vascular grafts (TEVG) was enabled by functionalizing the textile scaffold with ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles. The resulting MR-imageable grafts (iTEVG) were monitored non-invasively throughout their whole life-cycle, from initial quality control to longitudinal functional evaluation in an ovine model for up to 8 weeks.

Status and trends in the development of clinical diagnostic agents.

Contrast agents (CA) are routinely used in clinical practice to improve the diagnosis of diseases and to monitor therapy response. The majority of CA comprises small molecules accumulating at pathological sites due to vascular abnormalities, such as changes in perfusion and permeability. For many diseases, high diagnostic accuracy can be achieved with contrast-enhanced imaging.

Mesenchymal stem cells can be recruited to wounded tissue via hepatocyte growth factor-loaded biomaterials.

Mesenchymal stem cells (MSC) are precursor cells of mesodermal tissue and, because of their trophic phenotype, they are known to play beneficial roles in wound healing. In addition, various tissue engineering strategies are based on MSC/biomaterial constructs. As the isolation and expansion of MSCs is a long-term process, a major goal is to develop an endogenous stem cell recruitment system that circumvents all ex vivo steps generally used for tissue engineering.

Evolution of contrast agents for ultrasound imaging and ultrasound-mediated drug delivery.

Ultrasound (US) is one of the most frequently used diagnostic methods. It is a non-invasive, comparably inexpensive imaging method with a broad spectrum of applications, which can be increased even more by using bubbles as contrast agents (CAs). There are various different types of bubbles: filled with different gases, composed of soft- or hard-shell materials, and ranging in size from nano- to micrometers.