Comparative assessment of electronic nicotine delivery systems aerosol and cigarette smoke on endothelial cell migration: The Replica Project.

Introduction:
This article reports the results of a multi-center study aimed at replicating and extending the findings of a previous investigation on the effects of electronic cigarette (EC) aerosol and cigarette smoke on human umbilical vein endothelial cells (hUVECs) migration. The study also tested the effects of heated tobacco products (hTPs) aerosol on endothelial cells.

Key points:

* The study was conducted as a ring-study, involving four international laboratories, to verify the robustness and reliability of the results obtained in the replicated study.
* The laboratories performed an in vitro scratch wound assay on endothelial cells, using aqueous extracts (aqE) of EC aerosol, cigarette smoke, and hTPs aerosol.
* Consistently with the original study, the study observed a substantial reduction of the effects of aerosol from EC and hTPs on endothelial cell migration compared with cigarette smoke.
* Cigarette smoke reduced endothelial wound healing ability already at low concentrations (12.5%) and in a concentration-dependent manner, while EC and hTPs aerosol showed no effect on endothelial cells until 80% –100% concentrations.
* The study also found that the nicotine concentrations in the aqE samples of the 1R6F cigarette, Vype ePen3, IqOS 3 Duo, and Glo ™Pro were 12.8 μg/ml, 4.2 μg/ml, 8.4 μg/ml, and 4.5 μg/ml, respectively.
* The study concludes that the findings support the concept that altering cigarette smoke toxicant levels may modify biological responses to cigarette smoke and that EC and hTPs aerosol have reduced effects on endothelial cell migration compared with cigarette smoke.

Main message:
The study further confirms the importance of EC and tobacco heated products as a possible harm reduction strategy for cardiovascular diseases development in smokers. The replication of the original study and the inclusion of hTPs aerosol provide stronger evidence for the reduced effects of EC and hTPs aerosol on endothelial cell migration compared with cigarette smoke. The study highlights the need for further research on the long-term effects of EC and hTPs use on cardiovascular health.

Caruso M, Emma R, Distefano a, et al. Comparative assessment of electronic nicotine delivery systems aerosol and cigarette smoke on endothelial cell migration: The Replica Project. Drug testing and analysis. Published online July 25, 2022. doi:10.1002/dta.3349