The Effect of Closed-Eye Tear Film Conditions on Blood-Isolated Neutrophils,In Vitro

Purpose: Eyelid closure results in influx of neutrophils onto the ocular surface, which are non-responsive to inflammatory stimuli. This investigation examined whether incubation of blood-isolated neutrophils in closed-eye conditions induce a tear-film neutrophil phenotype.

Methods: Blood-isolated neutrophils were incubated combining various conditions: hypoxia, corneal epithelial cells (HCEC), artificial tear solution (ATS).

Results: A hypoxic environment induced no differential effect on membrane receptor expression. Incubation in the presence of HCEC resulted in membrane receptor upregulation and increase in caspase activation.

Conclusions: Hypoxia, corneal epithelial cell exposure, or artificial tear fluid are insufficient to replicate a tear-film neutrophil phenotype using blood-isolated neutrophils.