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Pre- and postmortem imaging of transplanted cells.

Andrzejewska A, Nowakowski A, Janowski M, Bulte JW, Gilad AA, Walczak P, Lukomska B - Int J Nanomedicine (2015)

Bottom Line: Therapeutic interventions based on the transplantation of stem and progenitor cells have garnered increasing interest.Further progress in this field is contingent upon access to techniques that facilitate an unambiguous identification and characterization of grafted cells.Following is a focused overview of the currently available cell detection and tracking methodologies that covers the entire spectrum from pre- to postmortem cell identification.

View Article: PubMed Central - PubMed

Affiliation: NeuroRepair Department, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.

ABSTRACT
Therapeutic interventions based on the transplantation of stem and progenitor cells have garnered increasing interest. This interest is fueled by successful preclinical studies for indications in many diseases, including the cardiovascular, central nervous, and musculoskeletal system. Further progress in this field is contingent upon access to techniques that facilitate an unambiguous identification and characterization of grafted cells. Such methods are invaluable for optimization of cell delivery, improvement of cell survival, and assessment of the functional integration of grafted cells. Following is a focused overview of the currently available cell detection and tracking methodologies that covers the entire spectrum from pre- to postmortem cell identification.

No MeSH data available.


Related in: MedlinePlus

Schematic outline of bioluminescence cells creation and their identification by BLI method in host body after transplantation.Abbreviation: BLI, bioluminescent imaging.
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f3-ijn-10-5543: Schematic outline of bioluminescence cells creation and their identification by BLI method in host body after transplantation.Abbreviation: BLI, bioluminescent imaging.

Mentions: The principle of BLI is based on the luciferase reaction that requires an enzyme (firefly luciferase), its substrate (D-luciferin or coelenterazine), ATP, and oxygen. This enzyme-catalyzed oxidation results in oxyluciferin, a product that, when decaying, emits photons. Photons are detected by specialized charge-coupled device (CCD) cameras that convert photons into electrons. The noise of the system is reduced by supercooling the CCD camera and mounting the camera in a light-tight chamber (Figure 3). The sensitivity of this imaging modality is dependent on several factors, including the optical properties and expression level of the reporter gene, the depth of labeled cells within the body, and the sensitivity of the detection device.103 The major challenge of in vivo BLI is that emitted photons must pass through the tissues and have to be detected outside the body. For that reason, detection of cells implanted superficially is much more effective than are deeper targets. As a general rule, the signal drops approximately tenfold for each 10 mm of tissue depth.104 In order to address the problem of tissue attenuation that limits sensitivity, significant effort has been directed toward improving the optical properties of imaging probes. The potential strategies include developing reporter genes with red-shifted emission profiles of photons known to have better tissue penetration, or developing new generations of substrates, such as CycLuc1, which offers significantly better pharmacokinetics and effectively results in an improved imaging signal.96,105 Another technique with the potential to improve detection of luciferase-expressing cells is based on the modification of ABC-transporter activity. These proteins are involved in the removal of xenobiotics from cells. The result of their inhibition is a higher accumulation of D-luciferin inside cells, and thus, an increased availability of substrate for the luciferase enzyme.106 An important advancement in BLI was the development of image processing algorithms for extracting spatial information from the imaging signal, referred to as optical tomography.107 Another quite interesting alternative is the use of bioluminescent luciferase from Gaussia princeps (GLuc), which is naturally secreted from cells in an active form. GLuc is present in body fluids. After the addition of the substrate to urine or serum, the measurement of the bioluminescent signal can provide information about the condition and viability of the transplanted cells.108


Pre- and postmortem imaging of transplanted cells.

Andrzejewska A, Nowakowski A, Janowski M, Bulte JW, Gilad AA, Walczak P, Lukomska B - Int J Nanomedicine (2015)

Schematic outline of bioluminescence cells creation and their identification by BLI method in host body after transplantation.Abbreviation: BLI, bioluminescent imaging.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4562754&req=5

f3-ijn-10-5543: Schematic outline of bioluminescence cells creation and their identification by BLI method in host body after transplantation.Abbreviation: BLI, bioluminescent imaging.
Mentions: The principle of BLI is based on the luciferase reaction that requires an enzyme (firefly luciferase), its substrate (D-luciferin or coelenterazine), ATP, and oxygen. This enzyme-catalyzed oxidation results in oxyluciferin, a product that, when decaying, emits photons. Photons are detected by specialized charge-coupled device (CCD) cameras that convert photons into electrons. The noise of the system is reduced by supercooling the CCD camera and mounting the camera in a light-tight chamber (Figure 3). The sensitivity of this imaging modality is dependent on several factors, including the optical properties and expression level of the reporter gene, the depth of labeled cells within the body, and the sensitivity of the detection device.103 The major challenge of in vivo BLI is that emitted photons must pass through the tissues and have to be detected outside the body. For that reason, detection of cells implanted superficially is much more effective than are deeper targets. As a general rule, the signal drops approximately tenfold for each 10 mm of tissue depth.104 In order to address the problem of tissue attenuation that limits sensitivity, significant effort has been directed toward improving the optical properties of imaging probes. The potential strategies include developing reporter genes with red-shifted emission profiles of photons known to have better tissue penetration, or developing new generations of substrates, such as CycLuc1, which offers significantly better pharmacokinetics and effectively results in an improved imaging signal.96,105 Another technique with the potential to improve detection of luciferase-expressing cells is based on the modification of ABC-transporter activity. These proteins are involved in the removal of xenobiotics from cells. The result of their inhibition is a higher accumulation of D-luciferin inside cells, and thus, an increased availability of substrate for the luciferase enzyme.106 An important advancement in BLI was the development of image processing algorithms for extracting spatial information from the imaging signal, referred to as optical tomography.107 Another quite interesting alternative is the use of bioluminescent luciferase from Gaussia princeps (GLuc), which is naturally secreted from cells in an active form. GLuc is present in body fluids. After the addition of the substrate to urine or serum, the measurement of the bioluminescent signal can provide information about the condition and viability of the transplanted cells.108

Bottom Line: Therapeutic interventions based on the transplantation of stem and progenitor cells have garnered increasing interest.Further progress in this field is contingent upon access to techniques that facilitate an unambiguous identification and characterization of grafted cells.Following is a focused overview of the currently available cell detection and tracking methodologies that covers the entire spectrum from pre- to postmortem cell identification.

View Article: PubMed Central - PubMed

Affiliation: NeuroRepair Department, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.

ABSTRACT
Therapeutic interventions based on the transplantation of stem and progenitor cells have garnered increasing interest. This interest is fueled by successful preclinical studies for indications in many diseases, including the cardiovascular, central nervous, and musculoskeletal system. Further progress in this field is contingent upon access to techniques that facilitate an unambiguous identification and characterization of grafted cells. Such methods are invaluable for optimization of cell delivery, improvement of cell survival, and assessment of the functional integration of grafted cells. Following is a focused overview of the currently available cell detection and tracking methodologies that covers the entire spectrum from pre- to postmortem cell identification.

No MeSH data available.


Related in: MedlinePlus