International Symposium organized by SFB738

International_Symposium_Flyer_20170623

Cells isolated from diseased explanted livers

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The International Journal of Artificial Organs (official journal of the European Society for Artificial Organs [ESAO]) published our paper on Isolation, characterization and cold storage of cells isolated from diseased explanted livers. Authors are Belaschk E, Rohn S, Mukiibi R, Reutzel-Selke A, Tang P, Sawitzki B, Pratschke J, Sauer IM and Mogl MT.

Livers discarded after standard organ retrieval are commonly used as a cell source for hepatocyte transplantation. Due to the scarcity of organ donors, this leads to a shortage of suitable cells for transplantation. Here, the isolation of liver cells from diseased livers removed during liver transplantation is studied and compared to the isolation of cells from liver specimens obtained during partial liver resection.
Hepatocytes from 20 diseased explanted livers (Ex-group) were isolated, cultured and stored at 4°C for up to 48 hours, and compared to hepatocytes isolated from the normal liver tissue of 14 liver lobe resections (Rx-group). The nonparenchymal cell fraction (NPC) was analyzed by flow cytometry to identify potential liver progenitor cells, and OptiPrep™ (Sigma-Aldrich) density gradient centrifugation was used to enrich the progenitor cells for immediate transplantation.
There were no differences in viability, cell integrity and metabolic activity in cell culture and survival after cold storage when comparing the hepatocytes from the Rx-group and the Ex-group. In some cases, the latter group showed tendencies of increased resistance to isolation and storage procedures. The NPC of the Ex-group livers contained considerably more EpCAM+ and significantly more CD90+ cells than the Rx-group. Progenitor cell enrichment was not sufficient for clinical application.
Hepatocytes isolated from diseased explanted livers showed the essential characteristics of being adequate for cell transplantation. Increased numbers of liver progenitor cells can be isolated from diseased explanted livers. These results support the feasibility of using diseased explanted livers as a cell source for liver cell transplantation.

Int J Artif Organs. 2017 May 23:0. doi: 10.5301/ijao.5000594. [Epub ahead of print]

Poster_Programm

Recellularization of rat livers: morphology and function

TERM
The Journal of Tissue Engineering and Regenerative Medicine accepted our paper Evolution of graft morphology and function after recellularization of decellularized rat liversfor publication.

Decellularization of livers is a well-established procedure. Data on different reseeding techniques or the functional evolution and re-organization processes of repopulated grafts remains limited.
We established a proprietary, customized bioreactor to repopulate decellularized rat livers (n=21) with primary rat hepatocytes (150 x 106 cells) via the hepatic artery and to subsequently evaluate graft morphology and function during seven days of ex vivo perfusion. Grafts were analyzed at 1h, 6h, 12h, 24h, 3d, 5d and 7d after recellularization (all n=3) by immunohistologic evaluation, hepatocyte-related enzyme (AST, ALT, LDH) and albumin measurement in the perfusate.
To the best of our knowledge, this is the first available protocol for repopulation of rat livers via the hepatic artery. Within the first 24 hours after repopulation, the hepatocytes seemed to migrate out of the vascular network and form clusters in the parenchymal space around the vessels. Graft function increased for the first 24 hours after repopulation with a significantly higher function compared to standard 2D culture after 24 hours. Thereafter, graft function constantly decreased with significantly lower values after six and seven days of perfusion, although histologically viable hepatocytes were found even after this period. Our data suggests that due to a constant loss of function, repopulated grafts should potentially be implanted as soon as cell engraftment and graft re-organization are completed.

Authors are Antje Butter, Khalid Aliyev, Karl-Herbert Hillebrandt, Nathanael Raschzok, Martin Kluge, Nicolai Seiffert, Peter Tang, Hendrik Napierala, Muhammad Imtiaz Ashraf, Anja Reutzel-Selke, Andreas Andreou, Johann Pratschke, Igor Maximilian Sauer, and Benjamin Struecker.

Bile: miRNA Pattern post OLT

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BIOMARKERS accepted our latest paper on "Bile: miRNA Pattern and Protein Based Biomarkers May Predict Acute Cellular Rejection after Liver Transplantation" for publication. Authors are Rosa Bianca Schmuck, Anja Reutzel-Selke, Nathanael Raschzok, Mehmet Haluk Morgul, Benjamin Struecker, Steffen Lippert, Cynthia de Carvalho Fischer, Moritz Schmelzle, Sabine Boas-Knoop, Marcus Bahra, Andreas Pascher, Johann Pratschke, and Igor M. Sauer.

Bile rather than blood depicts the local inflammation in the liver and may improve prediction and diagnosis of acute cellular rejection (ACR) after liver transplantation (OLT). Secretome and miRNAs were analyzed during the first two weeks and on clinical suspicion of ACR in the bile of 45 OLT recipients. Levels of CD44, CXCL9, miR-122, miR-133a, miR-148a and miR-194 were significantly higher in bile of patients who developed ACR within the first 6 months after OLT and during ACR. Analysis of secretome and miRNA in bile could further our understanding of the local inflammatory process during rejection.

Biomarkers. 2016 Aug 5:1-9. [Epub ahead of print]

LTx – microRNA signatures in peripheral blood ?

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BIOMARKERS accepted our latest paper on „microRNA signatures in peripheral blood fail to detect acute cellular rejection after liver transplantation“ for publication. Authors are N. Raschzok, A. Reutzel-Selke, R. Schmuck, L. Tannus, M. Morgul, C. Dietel, A. Leder, B. Struecker, S. Lippert, H. Sallmon, M. Schmelzle, M. Bartels, S. Jonas, J. Pratschke, and I.M. Sauer.

We investigated whether microRNA signatures in whole blood samples are associated with acute cellular rejection (ACR) after liver transplantation. Blood samples were collected using Paxgene technology and analyzed by microarrays and qRT-PCR.
microRNA signatures failed to distinguish between 19 patients with ACR and 16 controls. Let-7b-5p and let-7c were up-regulated in a subgroup of patients with ACR during the 6th and 7th postoperative day but failed in an independent validation of 20 patients.
microRNA signatures in whole blood processed by Paxgene technology are not suited for detection of ACR after liver transplantation.

WTC 2014 in San Francisco

WTC2014

Ben Strücker presented the latest results on „Perfusion Decellularization of Pig and Rat Livers Applying Undulating Surrounding Pressure Conditions“. Co-authors were A. Butter, K. Hillebrandt, R. Voitl, D. Polenz, A. Reutzel-Selke, K. Joehrens, D. Geisel, N. Raschzok, P. Neuhaus, J. Pratschke and I.M. Sauer.

Nathanael Raschzok presentation was entitled: „Perioperative Serum Levels of CXCL9 and CD44 Predict the Risk of Acute Cellular Rejection in Liver Graft Recipients“. Co-authors were N. Raschzok, A. Reutzel-Selke, R. Schmuck, M. Morgul, M. Bartels, G. Puhl, D. Seehofer, M. Bahra, A. Pascher, P. Neuhaus, J. Pratschke and I.M. Sauer.