P. gingivalis degrades JAM1 of gingival epithelium, causing penetration of LPS and PGN.

(A, B) Schematic illustration of the three-dimensional culture (A) and confocal microscopic cross-sectional images (B) of the three-dimensional culture of IHGE cells. Gingival epithelial tissues (WT or overexpressing JAM1) were infected with P. gingivalis for 30 min. Tissues were then fixed, stained with anti-JAM1 (white) and Alexa Fluor 568–conjugated phalloidin (magenta), and analyzed by confocal microscopy. Scale bars, 30 μm. (CG) Permeability to 40 kDa FITC-dextran (C), FITC–P. gingivalis LPS (D), FITC–P. gingivalis PGN (E), FITC–E. coli LPS (F), and FITC–S. aureus PGN (G) of gingival epithelial tissues (WT or overexpressing JAM1) infected with P. gingivalis. Three-dimensional tissues on culture inserts were infected with P. gingivalis and FITC-labeled tracer in the upper compartment. Following 30 min of incubation, the transmission of tracer from the upper compartment to the lower compartment was analyzed by spectrometry. Results are expressed as fold change relative to uninfected WT cells and are the means ± SD of seven technical replicates. *, p<0.05, one-tailed t test (closed testing procedure).