@article{SolgerKunzFinketal.2019,
  author    = {Solger, Franziska and Kunz, Tobias C. and Fink, Julian and Paprotka, Kerstin and Pfister, Pauline and Hagen, Franziska and Schumacher, Fabian and Kleuser, Burkhard and Seibel, J{\"u}rgen and Rudel, Thomas},
  title     = {A role of sphingosine in the intracellular survival of Neisseria gonorrhoeae},
  series = {Frontiers in Cellular and Infection Microbiology},
  volume    = {10},
  journal   = {Frontiers in Cellular and Infection Microbiology},
  publisher = {Frontiers Media},
  address   = {Lausanne},
  issn      = {2235-2988},
  doi       = {10.3389/fcimb.2020.00215},
  pages     = {12},
  year      = {2019},
  abstract  = {Obligate human pathogenic Neisseria gonorrhoeae are the second most frequent bacterial cause of sexually transmitted diseases. These bacteria invade different mucosal tissues and occasionally disseminate into the bloodstream. Invasion into epithelial cells requires the activation of host cell receptors by the formation of ceramide-rich platforms. Here, we investigated the role of sphingosine in the invasion and intracellular survival of gonococci. Sphingosine exhibited an anti-gonococcal activity in vitro. We used specific sphingosine analogs and click chemistry to visualize sphingosine in infected cells. Sphingosine localized to the membrane of intracellular gonococci. Inhibitor studies and the application of a sphingosine derivative indicated that increased sphingosine levels reduced the intracellular survival of gonococci. We demonstrate here, that sphingosine can target intracellular bacteria and may therefore exert a direct bactericidal effect inside cells.},
  language  = {en}
}
@article{CollenburgWalterBurgertetal.2016,
  author    = {Collenburg, Lena and Walter, Tim and Burgert, Anne and Mueller, Nora and Seibel, Juergen and Japtok, Lukasz and Kleuser, Burkhard and Sauer, Markus and Schneider-Schaulies, Sibylle},
  title     = {A Functionalized Sphingolipid Analogue for Studying Redistribution during Activation in Living T Cells},
  series = {The journal of immunology},
  volume    = {196},
  journal   = {The journal of immunology},
  publisher = {American Assoc. of Immunologists},
  address   = {Bethesda},
  issn      = {0022-1767},
  doi       = {10.4049/jimmunol.1502447},
  pages     = {3951 -- 3962},
  year      = {2016},
  abstract  = {Sphingolipids are major components of the plasma membrane. In particular, ceramide serves as an essential building hub for complex sphingolipids, but also as an organizer of membrane domains segregating receptors and signalosomes. Sphingomyelin breakdown as a result of sphingomyelinase activation after ligation of a variety of receptors is the predominant source of ceramides released at the plasma membrane. This especially applies to T lymphocytes where formation of ceramide-enriched membrane microdomains modulates TCR signaling. Because ceramide release and redistribution occur very rapidly in response to receptor ligation, novel tools to further study these processes in living T cells are urgently needed. To meet this demand, we synthesized nontoxic, azido-functionalized ceramides allowing for bio-orthogonal click-reactions to fluorescently label incorporated ceramides, and thus investigate formation of ceramide-enriched domains. Azido-functionalized C-6-ceramides were incorporated into and localized within plasma membrane microdomains and proximal vesicles in T cells. They segregated into clusters after TCR, and especially CD28 ligation, indicating efficient sorting into plasma membrane domains associated with T cell activation; this was abolished upon sphingomyelinase inhibition. Importantly, T cell activation was not abrogated upon incorporation of the compound, which was efficiently excluded from the immune synapse center as has previously been seen in Ab-based studies using fixed cells. Therefore, the functionalized ceramides are novel, highly potent tools to study the subcellular redistribution of ceramides in the course of T cell activation. Moreover, they will certainly also be generally applicable to studies addressing rapid stimulation-mediated ceramide release in living cells.},
  language  = {en}
}