Near infrared optical projection tomography for assessments of β-cell mass distribution in diabetes research.
By adapting OPT to include the capability of imaging in the near infrared (NIR) spectrum, we here illustrate the possibility to image larger bodies of pancreatic tissue, such as the rat pancreas, and to increase the number of channels (cell types) that may be studied in a single specimen. We further describe the implementation of a number of computational tools that provide: 1/ accurate positioning of a specimen's (in our case the pancreas) centre of mass (COM) at the axis of rotation (AR); 2/ improved algorithms for post-alignment tuning which prevents geometric distortions during the tomographic reconstruction and 3/ a protocol for intensity equalization to increase signal to noise ratios in OPT-based BCM determinations. In addition, we describe a sample holder that minimizes the risk for unintentional movements of the specimen during image acquisition. Together, these protocols enable assessments of BCM distribution and other features, to be performed throughout the volume of intact pancreata or other organs (e.g. in studies of islet transplantation), with a resolution down to the level of individual islets of Langerhans.
Umeå Centre for Molecular Medicine, Umeå University.
Anna U
AU
Eriksson
Christoffer
C
Svensson
Andreas
A
Hörnblad
Abbas
A
Cheddad
Elena
E
Kostromina
Maria
M
Eriksson
Nils
N
Norlin
Antonello
A
Pileggi
James
J
Sharpe
Fredrik
F
Georgsson
Tomas
T
Alanentalo
Ulf
U
Ahlgren
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000473:pathology*; D050417:Insulin-Secreting Cells / Q000473:pathology*; D051379:Mice; D051381:Rats; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D041622:Tomography, Optical / Q000379:methods*