TY  - JOUR
A1  - Weiss, Esther
A1  - Schlegel, Jan
A1  - Terpitz, Ulrich
A1  - Weber, Michael
A1  - Linde, Jörg
A1  - Schmitt, Anna-Lena
A1  - Hünniger, Kerstin
A1  - Marischen, Lothar
A1  - Gamon, Florian
A1  - Bauer, Joachim
A1  - Löffler, Claudia
A1  - Kurzai, Oliver
A1  - Morton, Charles Oliver
A1  - Sauer, Markus
A1  - Einsele, Hermann
A1  - Loeffler, Juergen
T1  - Reconstituting NK Cells After Allogeneic Stem Cell Transplantation Show Impaired Response to the Fungal Pathogen Aspergillus fumigatus
JF  - Frontiers in Immunology
N2  - Delayed natural killer (NK) cell reconstitution after allogeneic stem cell transplantation (alloSCT) is associated with a higher risk of developing invasive aspergillosis. The interaction of NK cells with the human pathogen Aspergillus (A.) fumigatus is mediated by the fungal recognition receptor CD56, which is relocated to the fungal interface after contact. Blocking of CD56 signaling inhibits the fungal mediated chemokine secretion of MIP-1α, MIP-1β, and RANTES and reduces cell activation, indicating a functional role of CD56 in fungal recognition. We collected peripheral blood from recipients of an allograft at defined time points after alloSCT (day 60, 90, 120, 180). NK cells were isolated, directly challenged with live A. fumigatus germ tubes, and cell function was analyzed and compared to healthy age and gender-matched individuals. After alloSCT, NK cells displayed a higher percentage of CD56\(^{bright}\)CD16\(^{dim}\) cells throughout the time of blood collection. However, CD56 binding and relocalization to the fungal contact side were decreased. We were able to correlate this deficiency to the administration of corticosteroid therapy that further negatively influenced the secretion of MIP-1α, MIP-1β, and RANTES. As a consequence, the treatment of healthy NK cells ex vivo with corticosteroids abrogated chemokine secretion measured by multiplex immunoassay. Furthermore, we analyzed NK cells regarding their actin cytoskeleton by Structured Illumination Microscopy (SIM) and flow cytometry and demonstrate an actin dysfunction of NK cells shown by reduced F-actin content after fungal co-cultivation early after alloSCT. This dysfunction remains until 180 days post-alloSCT, concluding that further actin-dependent cellular processes may be negatively influenced after alloSCT. To investigate the molecular pathomechansism, we compared CD56 receptor mobility on the plasma membrane of healthy and alloSCT primary NK cells by single-molecule tracking. The results were very robust and reproducible between tested conditions which point to a different molecular mechanism and emphasize the importance of proper CD56 mobility.
KW  - natural killer cell
KW  - stem cell transplantation
KW  - corticosteroids
KW  - CCL3
KW  - CCL4
KW  - CCL5
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-212581
SN  - 1664-3224
VL  - 11
ER  - 
TY  - JOUR
A1  - Götz, Ralph
A1  - Panzer, Sabine
A1  - Trinks, Nora
A1  - Eilts, Janna
A1  - Wagener, Johannes
A1  - Turrà, David
A1  - Di Pietro, Antonio
A1  - Sauer, Markus
A1  - Terpitz, Ulrich
T1  - Expansion Microscopy for Cell Biology Analysis in Fungi
JF  - Frontiers in Microbiology
N2  - Super-resolution microscopy has evolved as a powerful method for subdiffraction-resolution fluorescence imaging of cells and cellular organelles, but requires sophisticated and expensive installations. Expansion microscopy (ExM), which is based on the physical expansion of the cellular structure of interest, provides a cheap alternative to bypass the diffraction limit and enable super-resolution imaging on a conventional fluorescence microscope. While ExM has shown impressive results for the magnified visualization of proteins and RNAs in cells and tissues, it has not yet been applied in fungi, mainly due to their complex cell wall. Here we developed a method that enables reliable isotropic expansion of ascomycetes and basidiomycetes upon treatment with cell wall degrading enzymes. Confocal laser scanning microscopy (CLSM) and structured illumination microscopy (SIM) images of 4.5-fold expanded sporidia of Ustilago maydis expressing fluorescent fungal rhodopsins and hyphae of Fusarium oxysporum or Aspergillus fumigatus expressing either histone H1-mCherry together with Lifeact-sGFP or mRFP targeted to mitochondria, revealed details of subcellular structures with an estimated spatial resolution of around 30 nm. ExM is thus well suited for cell biology studies in fungi on conventional fluorescence microscopes.
KW  - Expansion microscopy
KW  - fluorescence microscopy
KW  - fungi
KW  - sporidia
KW  - hyphae
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202569
SN  - 1664-302X
VL  - 11
ER  -