Molecular imaging is a new and rapidly emerging biomedical research discipline that involves the non-invasive detection of changes in the expression of genes, molecules and cells in vivo over time. It may be defined as the visual representation, characterization and quantification of biological processes at the cellular and molecular levels within intact living organisms.
Molecular imaging is a novel multidisciplinary field of research that brings together the following areas of expertise:
- anatomy & cell biology
- molecular, cell and developmental biology;
- radiochemistry and synthetic and medicinal chemistry;
- diagnostic imaging.
As a result, the images reflect cellular and molecular mechanisms of disease in an in vivo context. Therefore, molecular changes that precede the onset of chronic diseases such as diabetes, cardiovascular disease, cancer can be detected, and may lead to the identification of novel disease markers that allow for the development of medical interventions prior to disease onset.
Research in molecular imaging can be applied to a wide array of questions in the basic and clinical sciences, such as:
- Imaging gene expression, protein-protein interactions, and cellular biochemical pathways.
- Monitoring of multiple molecular events simultaneously.
- Tracking the status of cell transplants.
- Monitoring changes in genes and cells prior to the manifestation of disease symptoms.
- Imaging the effects of drug, gene, and cell-based therapies over time.
The confluence of molecular biology, chemistry and innovative imaging technologies therefore creates the possibility of answering all of the above questions in a rapid and quantitative manner in the same animal over time. The driving force behind the emergence of molecular imaging as a strategy to investigate the above processes is multifaceted:
- Advances in molecular biology, genomics, proteomics and bioinformatics have placed an unprecedented amount of information in readily available databases.
- Development of new imaging probes has resulted in the formation of the Molecular Imaging and Contrast Agent Database, an initiative of the U.S. National Institutes of Health Roadmap, to foster research and development in molecular imaging.
- Small animal imaging instrumentation needs for molecular imaging has resulted in a number of companies developing “preclinical” imaging instrumentation, such as micro-PET and nano-SPECT scanners with integrated x-ray CT capabilities. Such imaging modalities have to be adapted for the increased resolution and sensitivity demanded by the imaging of small animal models of disease.
Therefore, investment in the training of highly qualified personnel, such as graduate students, is required to provide a uniquely trained workforce for leading the innovations in biomedical research through molecular imaging.