Molekulare MR-Bildgebung

Zusammenfassung.

Die medizinisch-biologische Grundlagenforschung erbrachte in den letzten Jahren einen rasanten Erkenntnisfortschritt für das funktionelle Verständnis über physiologische und pathologische Prozesse bis hinab auf molekulares Niveau. Gleichzeitig haben sich auch verschiedene bildgebende Techniken von der ursprünglichen Organdarstellung der Zellebene genähert und sind im Begriff, die Sichtbarmachung auch von molekularen Vorgängen zu etablieren. Neben anderen Verfahren wie PET und Nahinfrarotfluoreszenz weist die MRT einige vielversprechende Optionen und bereits heute erprobte Einsatzmöglichkeiten in der molekularen Bildgebung auf, wie z. B. die Visualisierung von Enzymaktivitäten, die Darstellung der Expression bestimmter Gene, die Sichtbarmachung von Oberflächenrezeptoren oder die spezifische Visualisierung von Zellen im Rahmen der Immunantwort. Gegenüber den anderen Modalitäten mit zum Teil höherer Sensitivität bietet die molekulare Magnetresonanztomographie (mMRT) insbesondere den Vorteil eines hohen räumlichen Auflösungsvermögens. Für die mMRT ist die weitere Verbesserung der Auflösung und die Entwicklung von molekular angreifenden Markern mit erhöhter Sensitivität und Spezifität eine wesentliche Voraussetzung. Der Stand der Entwicklung der mMRT wird anhand einer Literaturübersicht bisher durchgeführter experimenteller Studien und eigener Forschungsergebnisse an Gliomen dargestellt.

Molecular MR Imaging.

Basic medicobiological research in recent years has made rapid advances in the functional understanding of normal and pathological processes down to the molecular level. At the same time, various imaging modalities have developed from the depiction of organs to approaching the depiction of the cellular level and are about to make the visualization of molecular processes an established procedure. Besides other modalities like PET and near-infrared fluorescence, MR imaging offers some promising options for molecular imaging as well as some applications that have already been tested such as the visualization of enzyme activity, the depiction of the expression of certain genes, the visualization of surface receptors, or the specific demonstration of cells involved in the body's immune response. A major advantage of molecular magnetic resonance imaging (mMRI) over other more sensitive modalities is its high spatial resolution. However, the establishment of mMRI crucially relies on further improvements in resolution and the development of molecular markers for improving its sensitivity and specificity. The state of the art of mMRI is presented by giving a survey of the literature on experimental studies and reporting the results our study group obtained during investigation on gliomas.

Schlüsselwörter:

Molekulare Bildgebung - Magnetresonanztomographie - Gliome - Mikroglia - Makrophagen

Key words:

Molecular imaging - Magnetic resonance imaging - Gliomas - Microglia - Macrophages

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