CORESTA SSPT, October 8-12, 2023, Cancun, Mexico
Hollings, M1; Rothwell E1; Martin S1; Daunt, A1; Freiberg, G2; Bedford, R1;
Labcorp Early Development Laboratories Ltd., 1Harrogate, UK and 2Eye, UK
There is a current push to investigate emerging Next Generation Products (NGPs) including Electronic Nicotine Delivery System (ENDS) and Heated Tobacco Products (HTPs). 3D airway tissue models are a relevant method for analysis of toxicity for these aerosol products. These tissues have increased relevance over monolayer cell cultures as they have many attributes that are generally only seen in vivo; characteristics such as metabolic activity and increased physiological relevance.
MucilAir™ and SmallAir™ (1R6F only) (Epithelix Sarl, Switzerland) tissues were exposed using a Vitrocell® VC10® smoking robot; to 1R6F Kentucky Reference cigarettes (smoked to ISO 20778 for 64 minutes), a commercially available HTP (puffed to modified ISO 20778 for 180 minutes) and a commercially available ENDS (puffed to ISO 20768 for 180 minutes). Aerosol was diluted at varying concentrations with flowing air; 10, 8, 4 and 1 L/min for the 1R6F, and 2, 1, 0.5 L/min and an undiluted airflow for HTP and ENDS. Liquid traps were placed at the air liquid interface (ALI) and analysed for nicotine, which was used as a marker for delivered dose.
Following exposure cytotoxicity was measured via WST-8 and Lactate dehydrogenase (LDH) assays. Additionally, TEER, cytokine, histological and RNA analysis of tissues were performed to provide molecular insights.
Exposure of MucilAir™ and SmallAir™ to whole aerosol resulted in different levels of viability and cytotoxicity with significantly different IC50 values.
This study was a proof of concept suggesting that MucilAir™ tissues can be used to differentiate between combustible cigarettes or HTP and ENDS products with regards to cytotoxicity assessment. These tissues are also useful in elucidating pathways of cytotoxicity. Difference in response between MucilAir™ and SmallAir™ can be useful in determining appropriate tissue model to use depending on particle size of test aerosol.