Otmar Schmid, Ph.D. (Germany)

Dr. Schmid is head of the Pulmonary Aerosol Delivery Group at the Comprehensive Pneumology Center and Helmholtz Zentrum München (Munich, Germany) and he is Adjunct Assistant Professor at the Missouri University of Science and Technology (Rolla, MO, USA).

Research interests

His current research interests range from health risks associated with ambient aerosols, cigarette smoke and engineered nanomaterials to new opportunities for diagnostics and targeted drug delivery using nanomaterials. He has extensive experience in aerosol characterization and – most recently – he has developed methods for dose-controlled delivery of aerosols to animal models and cell culture models of the lung. He has published more than 70 peer-reviewed papers and book chapters, served on the boards of numerous professional associations, and acted as consultant to pharma industry and regulatory bodies.

Keynote – Nanomaterial dosimetry in inhalation toxicology: Bridging the gaps between in vitro and in vivo models as well as real world exposure

Aerosolized delivery of engineered nanomaterials (ENMs) to animal (in vivo) or cell-based (in vitro) models of the lung is a technological challenge, which typically requires highly skilled aerosol experts and advanced aerosol equipment for controlled ENM exposure. For translation of preclinical ENM toxicity into risk assessment it is expected that not only exposure levels, but tissue-delivered dose play an important role. Hence, it is essential to understand the relationship between exposure and tissue-delivered dose, which depends on various parameters including aerosol size, density and shape as well as lung morphology, respiratory conditions and exposure time.

In this talk, various methods for in vitro and in vivo testing of aerosolized ENMs will be discussed with particular emphasis on the tissue-delivered dose. For in vitro experiments air-liquid interface (ALI) rather than submerged cell cultures of the lung are more physiologic and offer the possibility for direct measurement of the tissue delivered dose using dosimetric methods such as Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Quartz Crystal Microbalance (QCM). An overview of currently available ALI cell exposure systems will be discussed with emphasis on aerosol-cell deposition efficiency and delivery rate. Similarly, animal inhalation systems will be presented in the context of lung-delivered dose (rates) and put into perspective by comparison with physiological doses encountered in real world exposure settings.

A dose-based comparison of in vitro and in vivo toxicity of ENMs is likely to provide insights into gaps between currently applied in vitro and in vivo testing strategies. The potential for bridging these gaps is related to the use of biomimetic and clinically relevant models of the lung and to our understanding of physiological doses encountered during realistic exposure scenarios.