March 2018
Evaluation of Phototoxicity of Ocular Medical and Combination Devices
March 28, 2018To address ocular device induced phototoxicity, an in vitro 3T3 Neutral Red Uptake Phototoxicity test (OECD 432) for chemicals has been modified. Soft contact lenses formulated with three different photo-absorbing compounds and chemical solutions of these compounds were evaluated....
The Assessment of Phototoxicity Using the 3T3 Neutral Red Uptake (NRU) Phototoxicity Assay and a Modified Photo-Direct Peptide Reactivity Assay (DPRA)
March 28, 2018Alternative methods, including the validated 3T3 Neutral Red Uptake (NRU) Phototoxicity assay (OECD TG 432) may be used as a pre-clinical test to address phototoxicity. Currently, there are no validated alternative test methods to identify photoallergens; however, there are several validated alternative test methods to address skin sensitization, including the Direct Peptide Reactivity Assay (DPRA) (OECD 442C). To address photoallergy, we utilized the 3T3 Phototoxicity assay in combination with a modified photo-DPRA assay to determine if these assays were able...
Human In Vitro Models for Respiratory Toxicology: Evaluation of Goblet Cell Hyperplasia, Mucus Production, and Ciliary Beating Assays
March 28, 2018Robust non-animal models and assays for pulmonary toxicology are required to make competent product development and risk assessments for new materials requiring toxicity testing. Three in vitro assays (goblet cell hyperplasia [GCH], ciliary beat frequency [CBF], and MUC5AC quantitation) were evaluated for performance and reproducibility. To assess these assays, 6 laboratories contributed data using a common protocol utilizing IL-13 as an inducer of adverse mucociliary-relevant tissue changes. MatTek EpiAirway™ and Epithelix MucilAir™ 3D tissue models were used to evaluate endpoints...
Use of Ex Vivo Precision-Cut Lung Slices as a Screening Tool for Potential Respiratory Toxicity of E-Liquids
March 28, 2018E-vapor product liquids contain a variety of ingredient combinations that should be assessed for human risk. One human lung-relevant testing platform with reasonable throughput, is human precision-cut lung slices (HuPCLS). HuPCLS are arguably the most complex non-animal model of the lung, retaining native architecture and immune-competent cells over multi-week culture periods. HuPCLS were exposed to three concentrations (0.1%, 0.5%, and 1.2%) of propylene glycol (PG; an E-vapor product constituent) continuously for 16-days. Exposure-effects were evaluated biochemically (WST-8 assay) and histologically (viability...
Oral Irritation Assessment of Electronic Liquids Using an In Vitro Oral Testing Model
March 28, 2018While data are still being collected and analyzed, there were at least 1,300 accidental electronic liquid (e-liquid) exposures reported as of 2013. Deaths have occurred as a result of ingestion of e-liquid with the effects being attributed primarily to nicotine. The Food and Drug Administration (FDA) sought to regulate e-liquid through the Tobacco Control Act passed in 2009. In 2014, the FDA issued its “Deeming” proposals for public comments, which covered e-liquid manufacturing; the Final Rule giving the FDA authority to...
Nicotine Characterization of an In Vitro Inhalation Exposure System Using Conventional and Next-Generation Tobacco Products: A US/UK Inter-Laboratory Comparison
March 28, 2018The US-FDA has regulatory authority over tobacco products, including conventional cigarettes and next generation products (NGPs) such as e-cigarettes and tobacco heating products (THPs). There is a desire by the industry, regulator and animal protection organizations to incorporate non-animal test methods for tobacco product and NGP assessment. When assessing respiratory effects in vitro, reliable exposure systems that deliver aerosols to cellular/tissue cultures at the air-liquid interface are needed....