97 Transferability and Reproducibility of Exposed Air-Liquid Interface co-Culture Lung Models

Abstract

The establishment of reliable and robust in vitro models for hazard assessment, moving away from animal testing, requires evaluation of model transferability and reproducibility. Lung models that can be exposed via the air, by means of an air-liquid interface are promising in vitro models for evaluating the safety of nanomaterials (NMs) after inhalation exposure. We performed an inter-laboratory comparison study to evaluate the transferability and reproducibility of a lung model consisting of the human bronchial cell line Calu-3 as monoculture and, to increase the relevance of the model, also as co-culture with macrophages (derived from the THP-1 monocyte cell line or from human blood monocytes). Exposure employed the VITROCELL® Cloud12 system at physiologically relevant doses. Overall, the results of the seven participating laboratories are quite similar. No effects of lipopolysaccharide (LPS), quartz (DQ12) or titanium dioxide (TiO2) NM-105 exposure on cell viability and barrier integrity were seen in the monoculture and co-culture models. Most laboratories showed that LPS induced cytokine release in the co-culture models, but not the monoculture model. Exposure to DQ12 or TiO2 did not increase cytokine release, probably due to too low deposited doses. Interlaboratory variability indicated acceptable variation for cell viability measurements and relatively high variation for cytokine measurements. Based on the transferability and reproducibility of the model and its air exposure we are confident that, based on detailed SOPs, performing a new round of interlaboratory comparison, and increasing the deposited doses of NMs, these models may be taken further towards a possible OECD guideline.