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Hannover, Germany

Deschl U.,Boehringer Ingelheim | Vogel J.,Boehringer Ingelheim | Aufderheide M.,Cultex Laboratories GmbH
Experimental and Toxicologic Pathology | Year: 2011

Respiratory diseases like asthma or COPD are gaining more and more importance worldwide due to an increased exposure of humans to inhalable compounds such as cigarette smoke, diesel exhaust or other forms of environmental pollution. Therefore, a high impact on national health systems is expected, meaning long-term treatment, with periodic examinations accompanied by high costs. Although a number of efficient drugs for these disease patterns, like Tiotropium (antimuscarinic), Salmetron (β-antagonist) or corticosteroids, are already available, a great deal of effort has to be put into the development of new drugs and therapy concepts. In this context, in vitro methods may be useful to establish more efficient prescreening procedures to analyze, for example, the toxicity of new compounds during the research and development process. These studies should aim to achieve a better selection of substances relevant for further development and a final reduction in the number of animal experiments. Therefore, we established an in vitro exposure device that allows the analysis of inhalable compounds for their pharmacological and toxicological effects. This CULTEX ® device is composed of an exposure entity representing the in vivo respiratory air compartment and a basal feeding compartment representing the subepithelium. Both compartments are connected by porous transwells on which cells form an epithelium-like cell layer. We have used this system for exposing human lung cells directly to liquid aerosols and present the first data with regard to aerosolized model substances. © 2010.

Nara H.,Japan Tobacco Inc. | Fukano Y.,Japan Tobacco Inc. | Nishino T.,Japan Tobacco Inc. | Aufderheide M.,Cultex Laboratories GmbH
Experimental and Toxicologic Pathology | Year: 2013

For the biological evaluation of cigarette smoke in vitro, the particulate phase (PP) and the gas vapor phase (GVP) of mainstream smoke have usually been collected individually and exposed to biological material such as cultured cells. Using this traditional method, the GVP is collected by bubbling in an aqueous solution such as phosphate-buffered saline (PBS). In such a way the water-insoluble GVP fraction is excluded from the GVP, meaning that the toxic potential of the water-insoluble GVP fraction has hardly been investigated so far. In our experiments we used a direct exposure method to expose cells at the air-liquid interface (ALI) to the water-insoluble GVP fraction for demonstrating its toxicological/biological activity.In order to isolate the water-insoluble GVP fraction from mainstream smoke, the GVP was passed through 6 impingers connected in series with PBS. After direct exposure of Chinese hamster ovary cells (CHO-K1) with the water-insoluble GVP fraction in the CULTEX® system its cytotoxicity was assayed by using the neutral red uptake assay. The water-insoluble GVP fraction was proven to be less cytotoxic than the water-soluble GVP fraction, but showed a significant effect in a dose-dependent manner. The results of this study showed that the direct exposure of cultivated cells at the air-liquid interface offers the possibility to analyze the biological and toxicological activities of all fractions of cigarette smoke including the water-insoluble GVP fraction. © 2012 Elsevier GmbH.

Emura M.,M/A-COM | Aufderheide M.,M/A-COM | Mohr U.,Cultex Laboratories GmbH
Experimental and toxicologic pathology : official journal of the Gesellschaft für Toxikologische Pathologie | Year: 2015

Recent advancement in research on stem/progenitor cells of respiratory organs is breathtaking, benefiting from the rapid development of technology to create transgenic mice. There is now a great deal of knowledge capable of direct translation from mice to humans. Nevertheless, one has to be careful, since there may be unexpected pitfalls. First of all, there are differences anatomically, histologically and ultrastructurally in the airway epithelia of the two species. In parallel with these structural differences, regionally specific cell types behave and function, particularly in regenerative instances, differently between the two species, at least to some extent. From the viewpoint of important human respiratory diseases, one of the most susceptible regions of the respiratory tract is the bronchiole. In our approach to develop in vitro systems utilizing human bronchiolar epithelial cells, we are currently leaning on the data obtained from mouse studies in spite of the above-mentioned species differences. With the help of such in vitro systems we should be able to investigate the damaging effects and mechanisms of environmental pollutants in the human respiratory epithelium and consequently achieve results useful for quantitative analyses of the impact on human respiratory health. While pursuing this goal, the mouse data have suggested that it should be worthwhile to pay close attention to the stem/progenitor cells contained in the human bronchiolar epithelia and eventually make use of them. The mouse data have further shown that these stem/progenitor cells possess a very close association with the immature and variant club cells and the neuroendocrine cells, and our own unpublished preliminary data with human cells are, apparently, at least partly consistent with what the mouse data are telling us. Copyright © 2014 Elsevier GmbH. All rights reserved.

Aufderheide M.,Cultex Laboratories GmbH | Scheffler S.,Cultex Laboratories GmbH | Mohle N.,Cultex Laboratories GmbH | Halter B.,Halter Engineering GmbH
Analytical and Bioanalytical Chemistry | Year: 2011

In the field of inhalation toxicology, progress in the development of in vitro methods and efficient exposure strategies now offers the implementation of cellular-based systems. These can be used to analyze the hazardous potency of airborne substances like gases, particles, and complex mixtures (combustion products). In addition, the regulatory authorities require the integration of such approaches to reduce or replace animal experiments. Although the animal experiment currently still has to provide the last proof of the toxicological potency and classification of a certain compound, in vitro testing is gaining more and more importance in toxicological considerations. This paper gives a brief characterization of the CULTEX® Radial Flow System exposure device, which allows the exposure of cultivated cells as well as bacteria under reproducible and stable conditions for studying cellular and genotoxic effects after the exposure at the air-liquid or air-agar interface, respectively. A commercial bronchial epithelial cell line (16HBE14o-) as well as Salmonella typhimurium tester strains were exposed to smoke of different research and commercial available cigarettes. A dose-dependent reduction of cell viability was found in the case of 16HBE14o- cells; S. typhimurium responded with a dose-dependent induction of revertants. The promising results recommend the integration of cellular studies in the field of inhalation toxicology and their regulatory acceptance by advancing appropriate validation studies. © 2011 The Author(s).

Aufderheide M.,Cultex Laboratories GmbH | Halter B.,Halter Engineering GmbH | Mohle N.,Cultex Laboratories GmbH
BioMed Research International | Year: 2013

The EU Regulation on Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) demands the implementation of alternative methods for analyzing the hazardous effects of chemicals including particulate formulations. In the field of inhalation toxicology, a variety of in vitro models have been developed for such studies. To simulate the in vivo situation, an adequate exposure device is necessary for the direct exposure of cultivated lung cells at the air-liquid interface (ALI). The CULTEX RFS fulfills these requirements and has been optimized for the exposure of cells to atomized suspensions, gases, and volatile compounds as well as micro- and nanosized particles. This study provides information on the construction and functional aspects of the exposure device. By using the Computational Fluid Dynamics (CFD) analysis, the technical design was optimized to realize a stable, reproducible, and homogeneous deposition of particles. The efficiency of the exposure procedure is demonstrated by exposing A549 cells dose dependently to lactose monohydrate, copper(II) sulfate, copper(II) oxide, and micro- and nanoparticles. All copper compounds induced cytotoxic effects, most pronounced for soluble copper(II) sulfate. Micro- and nanosized copper(II) oxide also showed a dose-dependent decrease in the cell viability, whereby the nanosized particles decreased the metabolic activity of the cells more severely. © 2013 Michaela Aufderheide et al.

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