@article{GereckeEdlichGiulbudagianetal.2017,
  author    = {Gerecke, Christian and Edlich, Alexander and Giulbudagian, Michael and Schumacher, Fabian and Zhang, Nan and Said, Andre and Yealland, Guy and Lohan, Silke B. and Neumann, Falko and Meinke, Martina C. and Ma, Nan and Calderon, Marcelo and Hedtrich, Sarah and Schaefer-Korting, Monika and Kleuser, Burkhard},
  title     = {Biocompatibility and characterization of polyglycerol-based thermoresponsive nanogels designed as novel drug-delivery systems and their intracellular localization in keratinocytes},
  series = {Nanotoxicology},
  volume    = {11},
  journal   = {Nanotoxicology},
  publisher = {Routledge, Taylor \& Francis Group},
  address   = {Abingdon},
  issn      = {1743-5390},
  doi       = {10.1080/17435390.2017.1292371},
  pages     = {267 -- 277},
  year      = {2017},
  abstract  = {Novel nanogels that possess the capacity to change their physico-chemical properties in response to external stimuli are promising drug-delivery candidates for the treatment of severe skin diseases. As thermoresponsive nanogels (tNGs) are capable of enhancing penetration through biological barriers such as the stratum corneum and are taken up by keratinocytes of human skin, potential adverse consequences of their exposure must be elucidated. In this study, tNGs were synthesized from dendritic polyglycerol (dPG) and two thermoresponsive polymers. tNG_dPG_tPG are the combination of dPG with poly(glycidyl methyl ether-co-ethyl glycidyl ether) (p(GME-co-EGE)) and tNG_dPG_pNIPAM the one with poly(N-isopropylacrylamide) (pNIPAM). Both thermoresponsive nanogels are able to incorporate high amounts of dexamethasone and tacrolimus, drugs used in the treatment of severe skin diseases. Cellular uptake, intracellular localization and the toxicological properties of the tNGs were comprehensively characterized in primary normal human keratinocytes (NHK) and in spontaneously transformed aneuploid immortal keratinocyte cell line from adult human skin (HaCaT). Laser scanning confocal microscopy revealed fluorescently labeled tNGs entered into the cells and localized predominantly within lysosomal compartments. MTT assay, comet assay and carboxy-H2DCFDA assay, demonstrated neither cytotoxic or genotoxic effects, nor any induction of reactive oxygen species of the tNGs in keratinocytes. In addition, both tNGs were devoid of eye irritation potential as shown by bovine corneal opacity and permeability (BCOP) test and red blood cell (RBC) hemolysis assay. Therefore, our study provides evidence that tNGs are locally well tolerated and underlines their potential for cutaneous drug delivery.},
  language  = {en}
}
@article{EdlichVolzBrodwolfetal.2018,
  author    = {Edlich, Alexander and Volz, Pierre and Brodwolf, Robert and Unbehauen, Michael and Mundhenk, Lars and Gruber, Achim D. and Hedtrich, Sarah and Haag, Rainer and Alexiev, Ulrike and Kleuser, Burkhard},
  title     = {Crosstalk between core-multishell nanocarriers for cutaneous drug delivery and antigen-presenting cells of the skin},
  series = {Biomaterials : biomaterials reviews online},
  volume    = {162},
  journal   = {Biomaterials : biomaterials reviews online},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0142-9612},
  doi       = {10.1016/j.biomaterials.2018.01.058},
  pages     = {60 -- 70},
  year      = {2018},
  abstract  = {Owing their unique chemical and physical properties core-multishell (CMS) nanocarriers are thought to underlie their exploitable biomedical use for a topical treatment of skin diseases. This highlights the need to consider not only the efficacy of CMS nanocarriers but also the potentially unpredictable and adverse consequences of their exposure thereto. As CMS nanocarriers are able to penetrate into viable layers of normal and stripped human skin ex vivo as well as in in vitro skin disease models the understanding of nanoparticle crosstalk with components of the immune system requires thorough investigation. Our studies highlight the biocompatible properties of CMS nanocarriers on Langerhans cells of the skin as they did neither induce cytotoxicity and genotoxicity nor cause reactive oxygen species (ROS) or an immunological response. Nevertheless, CMS nanocarriers were efficiently taken up by Langerhans cells via divergent endocytic pathways. Bioimaging of CMS nanocarriers by fluorescence lifetime imaging microscopy (FLIM) and flow cytometry indicated not only a localization within the lysosomes but also an energy-dependent exocytosis of unmodified CMS nanocarriers into the extracellular environment. (C) 2018 Elsevier Ltd. All rights reserved.},
  language  = {en}
}
@article{EdlichGereckeGiulbudagianetal.2016,
  author    = {Edlich, Alexander and Gerecke, Christian and Giulbudagian, Michael and Neumann, Falko and Hedtrich, Sarah and Schaefer-Korting, Monika and Ma, Nan and Calderon, Marcelo and Kleuser, Burkhard},
  title     = {Specific uptake mechanisms of well-tolerated thermoresponsive polyglycerol-based nanogels in antigen-presenting cells of the skin},
  series = {European Journal of Pharmaceutics and Biopharmaceutics},
  volume    = {116},
  journal   = {European Journal of Pharmaceutics and Biopharmaceutics},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0939-6411},
  doi       = {10.1016/j.ejpb.2016.12.016},
  pages     = {155 -- 163},
  year      = {2016},
  abstract  = {Engineered nanogels are of high value for a targeted and controlled transport of compounds due to the ability to change their chemical properties by external stimuli. As it has been indicated that nanogels possess a high ability to penetrate the stratum corneum, it cannot be excluded that nanogels interact with dermal dendritic cells, especially in diseased skin. In this study the potential crosstalk of the thermore-sponsive nanogels (tNGs) with the dendritic cells of the skin was investigated with the aim to determine the immunotoxicological properties of the nanogels. The investigated tNGs were made of dendritic polyglycerol (dPG) and poly(glycidyl methyl ether-co-ethyl glycidyl ether) (p(GME-co-EGE)), as polymer conferring thermoresponsive properties. Although the tNGs were taken up, they displayed neither cytotoxic and genotoxic effects nor any induction of reactive oxygen species in the tested cells. Interestingly, specific uptake mechanisms of the tNGs by the dendritic cells were depending on the nanogels cloud point temperature (Tcp), which determines the phase transition of the nanoparticle. The study points to caveolae-mediated endocytosis as being the major tNGs uptake mechanism at 37 degrees C, which is above the Tcp of the tNGs. Remarkably, an additional uptake mechanism, beside caveolae-mediated endocytosis, was observed at 29 degrees C, which is the Tcp of the tNGs. At this temperature, which is characterized by two different states of the tNGs, macropinocytosis was involved as well. In summary, our study highlights the impact of thermoresponsivity on the cellular uptake mechanisms which has to be taken into account if the tNGs are used as a drug delivery system.},
  language  = {en}
}