Université de Fribourg

Immune response to functionalized mesoporous silica nanoparticles for targeted drug delivery

Heidegger, Simon ; Gößl, Dorothée ; Schmidt, Alexandra ; Niedermayer, Stefan ; Argyo, Christian ; Endres, Stefan ; Bein, Thomas ; Bourquin, Carole

In: Nanoscale, 2015, vol. 8, no. 2, p. 938–948

Multifunctional mesoporous silica nanoparticles (MSN) have attracted substantial attention with regard to their high potential for targeted drug delivery. For future clinical applications it is crucial to address safety concerns and understand the potential immunotoxicity of these nanoparticles. In this study, we assess the biocompatibility and functionality of multifunctional MSN in freshly...

Université de Fribourg

TLR and RLR signaling are reprogrammed in opposite directions after detection of viral infection

Hotz, Christian ; Roetzer, Laurin C. ; Huber, Thomas ; Sailer, Andreas ; Oberson, Anne ; Treinies, Marina ; Heidegger, Simon ; Herbst, Tina ; Endres, Stefan ; Bourquin, Carole

In: The Journal of Immunology, 2015, vol. 195, no. 9, p. 4387–4395

Innate immune recognition of RNA is key for the initiation of immunity in response to viral infection. Although the factors controlling the detection of viral RNA by innate immune receptors in host cells are increasingly well understood, little is known about the dynamic changes in signaling after the initial triggering of these receptors. In this study, we report that preconditioning with the...

Université de Fribourg

Mycoplasma hyorhinis-contaminated cell lines activate primary innate immune cells via a protease-sensitive factor

Heidegger, Simon ; Jarosch, Alexander ; Schmickl, Martina ; Endres, Stefan ; Bourquin, Carole ; Hotz, Christian

In: PLoS ONE, 2015, vol. 10, no. 11, p. e0142523

Mycoplasma are a frequent and occult contaminant of cell cultures, whereby these prokaryotic organisms can modify many aspects of cell physiology, rendering experiments that are conducted with such contaminated cells problematic. Chronic Mycoplasma contamination in human monocytic cells lines has been associated with suppressed Toll-like receptor (TLR) function. In contrast, we show here that...

Université de Fribourg

Virus-associated activation of innate immunity induces rapid disruption of Peyer’s patches in mice

Heidegger, Simon ; Anz, David ; Stephan, Nicolas ; Bohn, Bernadette ; Herbst, Tina ; Fendler, Wolfgang Peter ; Suhartha, Nina ; Sandholzer, Nadja ; Kobold, Sebastian ; Hotz, Christian ; Eisenächer, Katharina ; Radtke-Schuller, Susanne ; Endres, Stefan ; Bourquin, Carole

In: Blood, 2013, p. -

Early in the course of infection, detection of pathogen-associated molecular patterns by innate immune receptors can shape the subsequent adaptive immune response. Here we investigate the influence of virus-associated innate immune activation on lymphocyte distribution in secondary lymphoid organs. We show for the first time that virus infection of mice induces rapid disruption of the Peyer's...

Université de Fribourg

TLR activation excludes circulating naive CD8+ T cells from gut-associated lymphoid organs in mice

Heidegger, Simon ; Kirchner, Sophie-Kathrin ; Stephan, Nicolas ; Bohn, Bernadette ; Suhartha, Nina ; Hotz, Christian ; Anz, David ; Sandholzer, Nadja ; Stecher, Bärbel ; Rüssmann, Holger ; Endres, Stefan ; Bourquin, Carole

In: The Journal of Immunology, 2013, vol. 190, no. 10, p. 5313–5320

The trafficking of effector T cells is tightly regulated by the expression of site-specific sets of homing molecules. In contrast, naive T cells are generally assumed to express a uniform pattern of homing molecules and to follow a random distribution within the blood and secondary lymphoid organs. In this study, we demonstrate that systemic infection fundamentally modifies the trafficking of...

Université de Fribourg

Cellular immunostimulation by CpG-sequence-coated DNA origami structures

Schüller, Verena J. ; Heidegger, Simon ; Sandholzer, Nadja ; Nickels, Philipp C. ; Suhartha, Nina A. ; Endres, Stefan ; Bourquin, Carole ; Liedl, Tim

In: ACS Nano, 2011, vol. 5, no. 12, p. 9696–9702

To investigate the potential of DNA origami constructs as programmable and noncytotoxic immunostimulants, we tested the immune responses induced by hollow 30-helix DNA origami tubes covered with up to 62 cytosine-phosphate-guanine (CpG) sequences in freshly isolated spleen cells. Unmethylated CpG sequences that are highly specific for bacterial DNA are recognized by a specialized receptor of the...

Université de Fribourg

Systemic cancer therapy with a small molecule agonist of Toll-like receptor 7 can be improved by circumventing TLR tolerance

Bourquin, Carole ; Hotz, Christian ; Noerenberg, Daniel ; Voelkl, Andreas ; Heidegger, Simon ; Roetzer, Laurin C. ; Storch, Bettina ; Sandholzer, Nadja ; Wurzenberger, Cornelia ; Anz, David ; Endres, Stefan

In: Cancer Research, 2011, vol. 71, no. 15, p. 5123-5133

Topical application of small molecule Toll-like receptor 7 (TLR7) agonists is highly effective for the treatment of skin tumors, whereas their systemic application has been largely unsuccessful for cancer therapy. One reason may be that repeated systemic application of TLR ligands can induce a state of immune unresponsiveness, termed TLR tolerance. We show here that a single injection of the TLR7...