TY - JOUR A1 - Karl, I. A1 - Jossberger-Werner, M. A1 - Schmidt, N. A1 - Horn, S. A1 - Goebeler, M. A1 - Leverkus, M. A1 - Wajant, H. A1 - Giner, T. T1 - TRAF2 inhibits TRAIL- and CD95L-induced apoptosis and necroptosis JF - Cell Death & Disease N2 - The relevance of the adaptor protein TNF receptor-associated factor 2 (TRAF2) for signal transduction of the death receptor tumour necrosis factor receptor1 (TNFR1) is well-established. The role of TRAF2 for signalling by CD95 and the TNF-related apoptosis inducing ligand (TRAIL) DRs, however, is only poorly understood. Here, we observed that knockdown (KD) of TRAF2 sensitised keratinocytes for TRAIL- and CD95L-induced apoptosis. Interestingly, while cell death was fully blocked by the pan-caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone (zVAD-fmk) in control cells, TRAF2-depleted keratinocytes were only partly rescued from TRAIL- and CD95L-induced cell death. In line with the idea that the only partially protective effect of zVAD-fmk on TRAIL- and CD95L-treated TRAF2-depleted keratinocytes is due to the induction of necroptosis, combined treatment with zVAD-fmk and the receptor interacting protein 1 (RIP1) inhibitor necrostatin-1 fully rescued these cells. To better understand the impact of TRAF2 levels on RIP1- and RIP3-dependent necroptosis and RIP3-independent apoptosis, we performed experiments in HeLa cells that lack endogenous RIP3 and HeLa cells stably transfected with RIP3. HeLa cells, in which necroptosis has no role, were markedly sensitised to TRAIL-induced caspase-dependent apoptosis by TRAF2 KD. In RIP3-expressing HeLa transfectants, however, KD of TRAF2 also strongly sensitised for TRAIL-induced necroptosis. Noteworthy, priming of keratinocytes with soluble TWEAK, which depletes the cytosolic pool of TRAF2-containing protein complexes, resulted in strong sensitisation for TRAIL-induced necroptosis but had only a very limited effect on TRAIL-induced apoptosis. The necroptotic TRAIL response was not dependent on endogenously produced TNF and TNFR signalling, since blocking TNF by TNFR2-Fc or anti-TNFα had no effect on necroptosis induction. Taken together, we identified TRAF2 not only as a negative regulator of DR-induced apoptosis but in particular also as an antagonist of TRAIL- and CD95L-induced necroptosis. KW - Nekrose KW - Apoptosis Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-119166 SN - 2041-4889 VL - 5 ER - TY - JOUR A1 - Stock, Benjamin A1 - Möckel, Sigrid A1 - Zander, Christine A1 - Heinsen, Helmut A1 - Bohnert, Simone A1 - Bohnert, Michael T1 - „Black esophagus“ – zwei Obduktionsfälle mit infektiöser Beteiligung JF - Rechtsmedizin N2 - „Black esophagus“ oder „akute Ösophagusnekrose“ (AÖN) ist eine seltene Erkrankung, die sich makroskopisch durch eine zirkumferente Schwarzverfärbung der Ösophagusmukosa mit abruptem Ende am gastroösophagealen Übergang auszeichnet. Die genaue Pathogenese ist unbekannt; es werden multifaktorielle Einflüsse wie z. B. Säurereflux, Ischämie und verringerte Schutzmechanismen der Mukosa als mögliche Ursachen diskutiert. Vorgestellt werden 2 Obduktionsfälle, die typische Befunde einer AÖN aufwiesen. Zusätzlich hatten Fall 1 eine Candida-Infektion und Fall 2 eine Appendizitis, sodass eine infektiöse Genese in beiden Fällen eine Rolle gespielt haben könnte. N2 - Black esophagus, also known as acute esophageal necrosis, is a rare disease characterized by a circumferential black discoloration of the esophageal mucosa with an abrupt stop at the gastroesophageal junction. The exact pathogenesis is unknown, but multifactorial influences, such as acid reflux, ischemia and reduced protective mechanisms of the mucosa are discussed as possible causes. Two autopsy cases are presented with typical signs of a black esophagus. The first case showed an infection with Candida albicans, the second one died of appendicitis, so in both cases an infectious genesis might have played a role. T2 - Black esophagus—Two autopsy cases with infectious involvement KW - Histopathologie KW - Blinddarmentzündung KW - Speiseröhre KW - Nekrose KW - Schleimhaut KW - Candida KW - Akute Ösophagusnekrose KW - Schleimhaut-Ulzera KW - Appendizitis KW - acute esophageal necrosis KW - histopathology KW - mucosal ulcers KW - appendicitis KW - Candida Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-325022 SN - 0937-9819 VL - 33 IS - 3 ER -