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  - Czakai, Kristin
A1  - Leonhardt, Ines
A1  - Dix, Andreas
A1  - Bonin, Michael
A1  - Linde, Joerg
A1  - Einsele, Hermann
A1  - Kurzai, Oliver
A1  - Loeffler, Jürgen
T1  - Krüppel-like Factor 4 modulates interleukin-6 release in human dendritic cells after in vitro stimulation with Aspergillus fumigatus and Candida albicans
JF  - Scientific Reports
N2  - Invasive fungal infections are associated with high mortality rates and are mostly caused by the opportunistic fungi Aspergillus fumigatus and Candida albicans. Immune responses against these fungi are still not fully understood. Dendritic cells (DCs) are crucial players in initiating innate and adaptive immune responses against fungal infections. The immunomodulatory effects of fungi were compared to the bacterial stimulus LPS to determine key players in the immune response to fungal infections. A genome wide study of the gene regulation of human monocyte-derived dendritic cells (DCs) confronted with A. fumigatus, C. albicans or LPS was performed and Krüppel-like factor 4 (KLF4) was identified as the only transcription factor that was down-regulated in DCs by both fungi but induced by stimulation with LPS. Downstream analysis demonstrated the influence of KLF4 on the interleukine-6 expression in human DCs. Furthermore, KLF4 regulation was shown to be dependent on pattern recognition receptor ligation. Therefore KLF4 was identified as a controlling element in the IL-6 immune response with a unique expression pattern comparing fungal and LPS stimulation.
KW  - gene regulation in immune cells
KW  - fungal host response
KW  - Aspergillus fumigatus
KW  - Candida albicans
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-181185
VL  - 6
ER  -