Health Australia (Commonwealth Union) – A recent study has found that even modest exposure to nicotine-free vapor has been found to inhibit the typical activity of neutrophils.
The study reveals that inhaling vapor produced by e-cigarettes may disrupt the normal functioning of frontline immune cells, as it suppresses their activity. These findings, published in the Journal of Allergy and Clinical Immunology, indicate that inhaling e-cigarette vapor could potentially harm neutrophils, which are the first line of defense in the human immune system. This discovery holds significance because previous research has demonstrated that damage inflicted on neutrophils by cigarette smoke can lead to long-term lung damage.
Researchers from the University of Birmingham conducted the study by collecting blood samples from individuals who had never smoked or vaped and were in good health. Subsequently, they exposed neutrophils extracted from these blood samples to 40 puffs of unflavored vape, a level of exposure previously considered low for daily use. Half of the samples were exposed to nicotine-containing vapor, while the other half encountered nicotine-free alternatives.
The results of the experiments showed that in both the nicotine-exposed and nicotine-free groups, the neutrophils remained alive but became immobilized, rendering them incapable of effectively responding to threats to the body.
Dr. Aaron Scott, the lead author of the study and an Associate Professor in Respiratory Science at the University of Birmingham, indicated that they found that after short, low-level exposure to e-cigarette vapor, the cells remain alive but can no longer move as effectively and are unable to carry out their normal protective functions. Interestingly, vapor from e-liquids which did not contain nicotine also had the same negative effects as vapor from e-liquids which did contain nicotine.
“E-cigarettes are a proven, lower harm, tool to help smokers quit smoking but our data adds to current evidence that e-cigarettes are not harmless and highlights the need for to fund longer-term studies in vapers.”
Subsequent experiments involving neutrophils exposed to e-cigarette vapor indicate that the suppression of the cells’ normal function may be driven by the accumulation of microfilaments within the cells, preventing them from re-arranging properly.
The researchers pointed out that generally, actin exists as small filaments within cells and can rearrange themselves into a network, aiding a cell in altering its shape. Neutrophils rely on this function to move towards and encircle potential threats, facilitating their destruction.
The research team observed a notable increase in the concentration of the filament F-actin within neutrophils that had been exposed to e-cigarette vapor, regardless of whether it contained nicotine or not. This accumulation of F-actin led to a decreased ability of immune cells to move and function in their usual manner.
David Thickett, a Professor in Respiratory Medicine at the University of Birmingham, Clinical Lead for the University Hospitals Birmingham (UHB) NHS Foundation Trust, and a co-author of the study, expressed concern, indicated that in a healthy state, neutrophils typically safeguard the lungs by migrating from the bloodstream to potential harm sites, where they employ various protective mechanisms to defend the lung. The observed impact of e-cigarette vapor on their mobility is therefore a matter of significant concern, as it suggests that regular e-cigarette use could elevate the risk of respiratory diseases.
Professor Liz Sapey, Director of the Institute of Inflammation and Ageing at the University of Birmingham and Honorary Acute Medicine and Respiratory Consultant Physician at UHB, who is also a co-author of the paper says “Smoking has a well-documented impact on neutrophils, and this study further shows the impact that e-cigarettes still have on the immune system. Neutrophils are heavily implicated in ageing and chronic obstructive disease and their relationship with tissue damage, and the impact of vaping in suppressing neutrophil activity regardless of nicotine could have long term implications for health.”
