Impact of E-Liquids on Phagocytosis, Escape and Invasion of Porphyromonas gingivalis
Year: 2026
Type: article
Abstract: This study seeks to understand the effects of electronic cigarettes on the oral microenvironment. Macrophages are paramount in the oral innate immune response against pathogens. Porphyromonas gingivalis is a Gram-negative bacterium that invades oral epithelial cells, escapes phagocytosis and is associated with the progression of periodontitis. We hypothesize that e-liquid treatments enhance P. gingivalis’s escape from post-macrophage phagocytosis and subsequent invasion into oral epithelial cells. THP-1-derived macrophages were polarized to M1 ± 1% e-liquids (±menthol or cinnamon). The M1 cellular morphology and surface area were determined after e-liquid treatments. Escherichia coli or P. gingivalis were added to M1 macrophages ± e-liquids. Phagocytosis and escape were determined by multiple assays. After e-liquid treatments and phagocytosis, OKF6/TERT-2 cells (oral epithelial cells) were exposed to M1 macrophages with intracellular P. gingivalis to evaluate escape and invasion. The results show that cinnamon e-liquids alter M1 morphology by diminishing pseudopodia extensions and actin stress fibers, which persist after a second polarization attempt. Phagocytosis of P. gingivalis by e-liquid-treated macrophages also decreases. Furthermore, P. gingivalis absolute escape and OKF6/TERT-2 cell invasion increase after menthol and cinnamon e-liquid treatments, respectively. Thus, following e-liquid exposure, phagocytosis and retention of P. gingivalis deteriorate.
Source: Pathogens
Language: English
Subfield: Periodontics
Field: Dentistry
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,654
OpenAlex ID: W7203829293