100 nm) have been used. Sicastar rather resembles SNPs that are used for industrial purposes and embodies a cytotoxic NP, which is supposed to evoke inflammatory responses to study ABT-199 datasheet cell communication processes in the coculture. Whereas AmOrSil is

prospectively envisaged for in vitro studies concerning drug and gene delivery and is proposed to be nontoxic. AmOrSil has a magnetic core, which may be useful for therapeutic applications (hyperthermia, magnetic resonance imaging or drug delivery) [10] and [11]. At first, the cytotoxicity (MTS and LDH) was studied on H441 and ISO-HAS-1 in MC and CC. Subsequently, NP uptake behaviour of the epithelial cells (H441) in CC was compared to the epithelial cells kept in MC by fluorescence intensity measurements. Furthermore, transport of NPs across the NP-exposed epithelial layer with subsequent uptake by the endothelial layer (ISO-HAS-1) on the opposite side of the Romidepsin transwell filter membrane was examined. In addition, NP-exposed cells were immunofluorescently counterstained for endosomal marker proteins such as clathrin heavy chain or caveolin-1 as well as flotillin-1 and -2 to examine specific uptake mechanisms such as clathrin-dependent or caveolae-dependent endocytosis. Finally,

the release of inflammatory mediators (IL-8, sICAM) has been examined after NP exposure to the apical side of the coculture (H441) to study inflammatory responses and cell communication Carnitine palmitoyltransferase II processes between epithelial and endothelial cells. In correlation with the uptake/transport experiments with the coculture, these results provide an approach to the hypothesis concerning indirect (forwarded inflammatory mediators caused by NPs) or direct (translocation of NPs) extrapulmonary effects caused by inhaled nanoparticles. AmOrSil nanoparticles were synthesised and delivered by Stefanie Utech (Department of Physical Chemistry of the Johannes Gutenberg University,

Mainz). These NPs are magnetic nanocapsules with magnetic iron oxide particles incorporated into a poly(organosiloxane) network that carries an additional PEO shell. The synthesis of the poly(organosiloxane) core–shell nanoparticles was performed in aqueous dispersion by co-condensation of a mixture of alkyldialkoxysilanes (diethoxydimethylsilane) and alkyltrialkoxysilanes (trimethoxymethylsilane and (chloromethylphenyl)trimethoxysilane, as functional monomers) in the presence of a surfactant. Rhodamine B was covalently incorporated into the entire SiOx-matrix. Magnetic iron oxide nanoparticles (γ-Fe2O3) with an average radius of 3.2 nm were encapsulated during the polycondensation process. Water-solubility was achieved via a grafting-on process, in which linear PEG (poly(ethylene glycol), MW: 1650 g/mol) was covalently attached to the poly(organosiloxane) surface. The magnetic nanocapsules have a primary particle radius of 48.1 nm. Synthesis and characterisation have previously been described by Utech et al.