Abstract
Purpose: :
To explore the effect of polyhexamethylene biguanide (PHMB), a disinfectant widely used in multipurpose contact lens solutions (MPS), on tight junction protein distribution and barrier function of cultured human corneal epithelial cell monolayers.
Methods: :
Cultured human corneal epithelial cells (HCEpiC) were exposed to 1-5 PPM PHMB for up to 2 hours. Tight junction structure and integrity were evaluated by confocal microscopy using ZO-1 antibody. Quantitative evaluation of PHMB on epithelial barrier function was determined by measuring transepithelial electrical resistance across HCEpiC grown on electric cell-substrate impedance sensing (ECIS) electrode arrays. The effect of PHMB on HCEpiC metabolic activity was determined by the alamarBlue assay.
Results: :
Overall, after exposure of HCEpiC to 1-5 PPM PHMB, ZO-1 distribution and fluorescent intensity on the cell surface appeared similar to the media control with continuous tight junctions and clear intercellular junctions. At all measured time points after exposure to PHMB at concentrations up to 5 PPM there was also no effect on the transepithelial electrical resistance as compared to the media control. PHMB at the above concentrations had no significant effect on metabolic activity, an index of cell viability.
Conclusions: :
PHMB at concentrations of 1-5 PPM, did not alter corneal barrier function or cell viability of HCEpiC, as compared to the media control. These results support the biocompatibility of the PHMB molecule as a disinfectant in multipurpose contact lens solutions.
Keywords: contact lens • cornea: epithelium • cell adhesions/cell junctions