TY  - JOUR
A1  - Ziegler, Sabrina
A1  - Weiss, Esther
A1  - Schmitt, Anna-Lena
A1  - Schlegel, Jan
A1  - Burgert, Anne
A1  - Terpitz, Ulrich
A1  - Sauer, Markus
A1  - Moretta, Lorenzo
A1  - Sivori, Simona
A1  - Leonhardt, Ines
A1  - Kurzai, Oliver
A1  - Einsele, Hermann
A1  - Loeffler, Juergen
T1  - CD56 Is a Pathogen Recognition Receptor on Human Natural Killer Cells
JF  - Scientific Reports
N2  - Aspergillus (A.) fumigatus is an opportunistic fungal mold inducing invasive aspergillosis (IA) in immunocompromised patients. Although antifungal activity of human natural killer (NK) cells was shown in previous studies, the underlying cellular mechanisms and pathogen recognition receptors (PRRs) are still unknown. Using flow cytometry we were able to show that the fluorescence positivity of the surface receptor CD56 significantly decreased upon fungal contact. To visualize the interaction site of NK cells and A. fumigatus we used SEM, CLSM and dSTORM techniques, which clearly demonstrated that NK cells directly interact with A. fumigatus via CD56 and that CD56 is re-organized and accumulated at this interaction site time-dependently. The inhibition of the cytoskeleton showed that the receptor re-organization was an active process dependent on actin re-arrangements. Furthermore, we could show that CD56 plays a role in the fungus mediated NK cell activation, since blocking of CD56 surface receptor reduced fungal mediated NK cell activation and reduced cytokine secretion. These results confirmed the direct interaction of NK cells and A. fumigatus, leading to the conclusion that CD56 is a pathogen recognition receptor. These findings give new insights into the functional role of CD56 in the pathogen recognition during the innate immune response.
KW  - pattern recognition receptors
KW  - fungal infection
KW  - Aspergillus fumigatus
KW  - natural killer cells
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170637
VL  - 7
IS  - 6138
ER  - 
TY  - THES
A1  - Mourad, Caroline
T1  - RNA-Interferenz humaner Natürlicher Killer-Zellen unter Einführung von siRNA mittels Lipofektion und Elektroporation
T1  - RNA interference in human natural killer cells by introduction of siRNA by lipofection and electroporation
N2  - Als Teil des angeborenen Immunsystems spielen Natürliche Killer(NK)- Zellen eine entscheidende Rolle in der Interaktion mit Pathogenen und Tumorzellen. Mithilfe der RNA-Interferenz bestimmter Gene wie beispielsweise CD56 könnten Hinweise auf die genaue Funktionsweise der NK-Zellen gewonnen werden. Ziel dieser Arbeit war es eine geeignete Transfektionsmethode zum Einführen von siRNA in NK-Zellen zu finden, welche eine hohe Transfektionseffizienz bei gleichzeitig hoher Zellviabilität aufweist. Hierfür wurden drei verschiedene Lipofektionsreagenzien und sechs verschiedene Elektroporationsprogramme verglichen. Zunächst wurde die Transfektionseffizienz mit an AF488 gekoppelter negativer siRNA per Fluoreszenzmikroskopie und Durchflusszytometrie evaluiert und jeweils das effizienteste Lipofektionsreagenz bzw. Elektroporationsprogramm ausgewählt. Mit diesen wurde anschließend eine Herunterregulation des CD56-Gens mit CD56-siRNA per RNA-Interferenz versucht. Die CD56-Gen-Expression wurde auf Proteinebene per Durchflusszytometrie und auf mRNA-Ebene per PCR (Polymerase-Ketten-Reaktion) evaluiert.
N2  - As a part of the innate immune system Natural Killer (NK) cells play a crucial role in the interaction with pathogens and tumor cells. Using RNA interference of special genes like CD56 may lead to a better understanding of the function of NK cells. The aim of this work was to find a suitable transfection method to introduce siRNA into NK cells which shows a high transfection efficiency and at the same time a high cell viability. Three different lipofection reagents and six different electroporation programs were compared. Initially, the transfection efficiency was evaluated with AF488-tagged negative siRNA by fluorescence microscopy and flow cytometry and the most efficient lipofection reagent and electroporation program were chosen. Using these a knockdown of the CD56 gene was tried by RNA interference with CD56 siRNA. The CD56 gene expression was evaluated on the protein level by flow cytometry and on the mRNA level by PCR (polymerase chain reaction).
KW  - RNS-Interferenz
KW  - Transfektion
KW  - Natürliche Killer-Zellen
KW  - natural killer cells
KW  - RNA interference
KW  - Elektroporation
KW  - electroporation
KW  - Lipofektion
KW  - lipofection
KW  - transfection
KW  - siRNA
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-185458
ER  -