TY  - JOUR
A1  - Leonhardt, Ines
A1  - Spielberg, Steffi
A1  - Weber, Michael
A1  - Albrecht-Eckardt, Daniela
A1  - Bläss, Markus
A1  - Claus, Ralf
A1  - Barz, Dagmar
A1  - Scherlach, Kirstin
A1  - Hertweck, Christian
A1  - Löffler, Jürgen
A1  - Hünniger, Kerstin
A1  - Kurzai, Oliver
T1  - The fungal quorum-sensing molecule farnesol activates innate immune cells but suppresses cellular adaptive immunity
JF  - mBio
N2  - Farnesol, produced by the polymorphic fungus Candida albicans, is the first quorum-sensing molecule discovered in eukaryotes. Its main function is control of C. albicans filamentation, a process closely linked to pathogenesis. In this study, we analyzed the effects of farnesol on innate immune cells known to be important for fungal clearance and protective immunity. Farnesol enhanced the expression of activation markers on monocytes (CD86 and HLA-DR) and neutrophils (CD66b and CD11b) and promoted oxidative burst and the release of proinflammatory cytokines (tumor necrosis factor alpha [TNF-\(\alpha\)] and macrophage inflammatory protein 1 alpha [MIP-1 \(\alpha\)]). However, this activation did not result in enhanced fungal uptake or killing. Furthermore, the differentiation of monocytes to immature dendritic cells (iDC) was significantly affected by farnesol. Several markers important for maturation and antigen presentation like CD1a, CD83, CD86, and CD80 were significantly reduced in the presence of farnesol. Furthermore, farnesol modulated migrational behavior and cytokine release and impaired the ability of DC to induce T cell proliferation. Of major importance was the absence of interleukin 12 (IL-12) induction in iDC generated in the presence of farnesol. Transcriptome analyses revealed a farnesol-induced shift in effector molecule expression and a down-regulation of the granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor during monocytes to iDC differentiation. Taken together, our data unveil the ability of farnesol to act as a virulence factor of C. albicans by influencing innate immune cells to promote inflammation and mitigating the Th1 response, which is essential for fungal clearance.
KW  - human dendritic cells
KW  - Pseudomonas aeruginosa
KW  - induced apoptosis
KW  - cytokine production
KW  - biofilm formation
KW  - Candida albicans
KW  - mouse model
KW  - systemic candidiasis
KW  - oxidative stress
KW  - carcinoma cells
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143756
VL  - 6
IS  - 2
ER  - 
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  -