Marcos Rojkinda, George Philipsb, Anna Mae Diehlb
Received 27 August 2010; accepted 1 September 2010. published online 04 October 2010.
Prediction and validation of cell alignment along microvessels as order principle to restore tissue architecture in liver regeneration. Hoehme S, Brulport M, Bauer A, Bedawy E, Schormann W, Hermes M, Puppe V, Gebhardt R, Zellmer S, Schwarz M, Bockamp E, Timmel T, Hengstler JG, Drasdo D. Proc Natl Acad Sci USA 2010 Jun 8;107(23):10371–10376. Copyright (2010) by the National Academy of Sciences; USA. Abstract reprinted with permission from the National Academy of Sciences.
Only little is known about how cells coordinately behave to establish functional tissue structure and restore microarchitecture during regeneration. Research in this field is hampered by a lack of techniques that allow quantification of tissue architecture and its development. To bridge this gap, we have established a procedure based on confocal laser scans, image processing, and three-dimensional tissue reconstruction, as well as quantitative mathematical modeling. As a proof of principle, we reconstructed and modeled liver regeneration in mice after damage by CCl(4), a prototypical inducer of pericentral liver damage. We have chosen the regenerating liver as an example because of the tight link between liver architecture and function: the complex microarchitecture formed by hepatocytes and microvessels, i.e. sinusoids, ensures optimal exchange of metabolites between blood and hepatocytes. Our model captures all hepatocytes and sinusoids of a liver lobule during a 16day regeneration process. The model unambiguously predicted a so-far unrecognized mechanism as essential for liver regeneration, whereby daughter hepatocytes align along the orientation of the closest sinusoid, a process which we named “hepatocyte-sinusoid alignment” (HSA). The simulated tissue architecture was only in agreement with the experimentally obtained data when HSA was included into the model and, moreover, no other likely mechanism could replace it. In order to experimentally validate the model of prediction of HSA, we analyzed the three-dimensional orientation of daughter hepatocytes in relation to the sinusoids. The results of this analysis clearly confirmed the model prediction. We believe our procedure is widely applicable in the systems biology of tissues.
a Department of Biochemistry and Molecular Biology, George Washington University Medical Center, Washington, DC, United States
b Division of Gatroenterology, Duke University Medical Center, Durham, NC, United States
© 2010 Published by Elsevier Inc.