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Robert-Koch-Prize awarded to Simon Moosburner
Today, Dr. med. Simon Moosburner received the Robert-Koch-Prize for one of the three best dissertations of the Charité - Universitätsmedizin Berlin in 2020 for his thesis titled  "Erweiterung der Spenderpopulation bei Lebertransplantation: Klinischer Bedarf und Entwicklung eines Kleintier-Lebermaschinenperfusionssystems (Expanding the donor pool for liver transplantation: clinical need and development of small animal liver perfusion system)".


Congratulations!
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Best Poster prize for Anna Pfefferkorn
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Anna Pfefferkorn won the Best Poster prize for our work on "Molecular and cellular mechanisms of Lipocalin-2 mediated renoprotection in kidney transplantation" at the Kongress für Nephrologie 2020, held in Berlin 1.-4. October, 2020!

Lipocalin-2 (Lcn2) is distinctly upregulated in kidney transplants and serves as an early marker of AKI, DGF and acute rejection. However, the functional role and mechanisms underlying Lcn2 upregulation remain largely unknown. Using a mouse model of kidney transplantation we recently demonstrated a renoprotective role of recombinant Lcn2:Siderophore:Fe (rLcn2). However, the molecular and cellular events underlying the renoprotective effects of rLcn2 in kidney allografts remain unclear. Elucidating these events forms the primary focus of the current study.
rLcn2 significantly lowered CD8+ T cells in the allograft, LN and blood at POD 7, whereas their number remained unaffected in spleen. Nevertheless, the number of CD4+ T Lymphocytes was reduced only in lymph nodes. NKG2D+CD8+T cells and CD27+CD11b+NKp46+NK cells were the most prominent subpopulations of the cytotoxic lymphocytes whose frequencies were significantly reduced in graft, spleen and blood with the treatment of rLcn2. Besides, a significantly reduced infiltration of monocytes/macrophages was also observed at POD-7 with the said treatment. Importantly, degranulation capacity and IFNg production of intragraft and splenic CD4+ and CD8+ T cells were impaired in the treated animals. Besides, rLcn2 lowered hypoxia and reoxygenation induced cytotoxicity of the primary RTECs, associated with reduced caspase-3 cleavage and activation of Erk and AKt signaling.

rLcn2 treatments differentially affects the relative frequencies and activation of various immune cell. Besides, rLcn2 depicts cytoprotective effect on murine primary RTECs during H/R, possibly via activation of Erk and Akt signaling.

CONGRATULATIONS !
Felix Krenzien received Ferdinand-Sauerbruch Prize 2020
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Priv.-Doz. Dr. Felix Krenzien received the Ferdinand-Sauerbruch Prize 2020 for his project and publication „The ILLS Laparoscopic Liver Surgery Fellow Skills Curriculum“ published in Annals of Surgery (online ahead of print).

Congratulations!

Laparoscopy is becoming the standard approach in liver surgery. As the degree of difficulty varies greatly from core skills to advanced procedures, strategies for teaching young surgeons need to be reconsidered. We here aimed to design a skills curriculum for LLR. Using the nominal group technique, 22 substeps of LLR were identified by 61 hepatobiliary surgeons. The raters were asked to rate (1) the difficulty of substeps and (2) the minimum number of times that the substep must be performed for mastery of the technique. According to the frequency of defined substeps, being estimated on the basis of high volume center experiences (n = 222 LLR; 1/2017-12/2018), the center's training capacity and defined goals for a 2-year fellowship were calculated.
Ten surgical substeps (45%) are routinely performed and can thus be taught sufficiently at centers carrying out ≥50 LLR in 2 years. As the mobilization of the right liver lobe and the dissection of the hepatic artery or portal vein is performed in only 27% and 28% of all LLR, respectively, sufficient training can only be provided at centers with ≥100 LLRs in 2 years. Mastery of complex parenchymal dissection (19%) and hilar lymphadenectomy (8%) can only be achieved in center performing ≥200 LLR in 2 years.
The authors suggest a stepwise approach for training of hepatobiliary fellows in LLR. Based on the estimated complexity of the substeps and the size of the center, not every substep can be learned within 2 years.

Authors are Felix Krenzien, Wenzel Schöning, Philipp Brunnbauer, Christian Benzing, Robert Öllinger, Matthias Biebl, Marcus Bahra, Nathanael Raschzok, Daniel Cherqui, David Geller, Ho-Seong Han, Go Wakabayashi, Moritz Schmelzle, Johann Pratschke, and the study group of the International Laparoscopic Liver Society (ILLS).
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Our manuscript "Depletion of donor dendritic cells ameliorates immunogenicity of both skin and hind limb transplants" has been accepted for publication in Frontiers in Immunology, section Alloimmunity and Transplantation. Authors are Muhammad Imtiaz Ashraf, Joerg Mengwasser, Anja Reutzel-Selke, Dietrich Polenz, Kirsten Führer, Steffen Lippert, Peter Tang, Edward Michaelis, Rusan Catar, Johann Pratschke, Christian Witzel, Igor M. Sauer, Stefan G. Tullius, and Barbara Kern.

Acute cellular rejection remains a significant obstacle affecting successful outcomes of organ transplantation including vascularized composite tissue allografts (VCA). Donor antigen presenting cells (APC), particularly dendritic cells (DC), orchestrate early alloimmune responses by activating recipient effector T cells. Employing a targeted approach, we investigated the impact of donor-derived conventional DC (cDC) and APC on the immunogenicity of skin and skin-containing VCA grafts, using mouse models of skin and hind limb transplantation.
By post-transplantation day 6, skin grafts demonstrated severe rejections, characterized by predominance of recipient CD4 T cells. In contrast, hind limb grafts showed moderate rejection, primarily infiltrated by CD8 T cells. While donor depletion of cDC and APC reduced frequencies, maturation, and activation of DC in all analysed tissues of skin transplant recipients, reduction in DC activities was only observed in the spleen of hind limb recipients. Donor cDC and APC depletion did not impact all lymphocyte compartments but significantly affected CD8 T cells and activated CD4 T in lymph nodes of skin recipients. Moreover, both donor APC and cDC depletion attenuated the Th17 immune response, evident by significantly reduced Th17 (CD4+IL-17+) cells in the spleen of skin recipients and reduced levels of IL-17E and lymphotoxin-α in the serum samples of both skin and hind limb recipients. In conclusion, our findings underscore the highly immunogenic nature of skin component in VCA. The depletion of donor APC and cDC mitigates the immunogenicity of skin grafts while exerting minimal impact on VCA.

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