Password Magazine — Issue 14: Healthcare
Molecular imaging and diagnostics |
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A paradigm shift in medical diagnostics
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+ Download By looking directly at the molecular processes underlying disease, molecular imaging offers tremendous potential for early detection and diagnosis of medical conditions and for the monitoring of therapies. Techniques now being developed depend upon a new generation of imaging systems offering exceptional sensitivity, and upon close cooperation between manufacturers of imaging systems, contrast media and pharmaceutical drugs. DownloadPDF-file of complete article (129kb) The role of molecular imaging in gene therapy
About
10% of the human population has or will develop at some stage an
inherited genetic disorder, and nearly 3000 medical conditions are
known to be caused by defects in just one gene. Cystic fibrosis,
sickle-cell anaemia and haemophilia are typical examples. Gene
therapy, where the absent or faulty gene is replaced by a
therapeutic gene, is a promising line of investigation for the
treatment of genetic disorders. One way of delivering the
therapeutic gene to a cell is inside a modified virus that enters
the cell and adds its ‘corrected’ genetic information to that of
the cell, which then divides to replicate the corrected genetic
information and eventually correct the medical condition.
The major contribution of molecular imaging to gene therapy is expected to be in targeting the gene at the correct site, for example, using heat-shock-protein (HSP)-targeted carriers, and in verifying that the therapeutic gene has been correctly delivered using a contrast medium targeted at the proteins released during the process of ‘gene expression’ (the manufacture of protein within the cells according to a specific genetic code dictated by the gene). Since human DNA contains around 30 000 genes, together capable of producing some hundreds of thousands of different proteins during gene expression, it would obviously not be feasible to produce contrast media capable of targeting every individual protein. Instead, a specially produced ‘reporter gene’ is delivered along with the therapeutic gene, and it is the protein produced by this gene that is targeted by the contrast medium. For more information
Dr Tobias Schaeffter |
