In vivo tomographic imaging of red-shifted fluorescent proteins

Biomedical Optics Express (Impact Factor: 3.65). 04/2011; 2(4):887-900. DOI: 10.1364/BOE.2.000887
Source: PubMed


We have developed a spectral inversion method for three-dimensional tomography of far-red and near-infrared fluorescent proteins in animals. The method was developed in particular to address the steep light absorption transition of hemoglobin from the visible to the far-red occurring around 600 nm. Using an orthotopic mouse model of brain tumors expressing the red-shifted fluorescent protein mCherry, we demonstrate significant improvements in imaging accuracy over single-wavelength whole body reconstructions. Furthermore, we show an improvement in sensitivity of at least an order of magnitude over green fluorescent protein (GFP) for whole body imaging. We discuss how additional sensitivity gains are expected with the use of further red-shifted fluorescent proteins and we explain the differences and potential advantages of this approach over two-dimensional planar imaging methods.

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Available from: Nikolaos Deliolanis, Sep 11, 2015
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    • "The impact of absorption and scattering could be mitigated by engineering FRET probes with donor-acceptor combinations utilizing fluorophores that are both excited and emit at longer wavelengths, such as red and near infrared fluorescent proteins. A recent study has shown the advantage of red-shifted fluorescent protein for in vivo tomographic imaging and demonstrated that, while autofluorescence is still a significant issue, it can be accounted for in the tomographic reconstruction to provide improved sensitivity, spatial localization and reduced image acquisition times [18]. The total acquisition time could be decreased further by automating the image acquisition process and investigating the trade-off between the number of time gates and the number of projection angles. "
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