Autoradiography remains the gold standard for measuring in vivo biodistribution of radiolabeled molecules. This imaging technique requires tissue sectioning and imaging on film or phosphor screen. A cryostat (CM 1850, Leica) operated and maintained by CMGI staff is available for sectioning frozen tissue. Tissue samples are fixed and frozen in O.C.T. (Tissue-Tek, USA) by liquid nitrogen, cryogen spray, or a dry ice slurry. The microtome allows sectioning in thicknesses from 1-60 µm in increments of 1 µm (1-10 µm), 2 µm (10-20 µm) and 5 µm (20-60 µm). Maximum specimen size is 55 mm, which allows longitudinal sectioning of a whole mouse (up to approximately 25 g). Protocols for autoradiography, histological staining (H&E) and immunohistochemistry are available.
Phosphor Imager: Autoradiographic specimen imaging is performed with storage phosphor screens, rather than film, using a STORM 860 Phosphor Imager (GE Healthcare; formerly Amersham Biosciences). Two phosphor screens (35 x 43 cm) with an intrinsic resolution of 50 µm are available. ImageQuant software provides qualitative and quantitative data analysis.
|PET||Inveon DPET||Siemens||~ 1.5 mm|
|PET||Focus 120||Siemens||~ 1.5 mm|
|PET||Primate 4||Siemens||~ 2.0 mm|
|PET||microPET II||Custom-built||~ 1 mm|
|SPECT||Inveon||Siemens||~ 0.5 – 3 mm|
|CT||Inveon||Siemens||~ 50 – 150 µm|
|MRI||Biospec 7T||Bruker||~ 100 – 250 µm|
|Ultrasound||Sequoia||Siemens||~ 100 – 500 µm|
|Optical||Maestro 2||CRi (Caliper)||~ 1 – 5 mm|
|Optical||IVIS 100||Xenogen (Caliper)||~ 1 – 5 mm|
|Autoradiography||Storm 860||Amersham Biosciences||~ 50 – 100 µm|