The Effect of Closed-Eye Tear Film Conditions on Blood-Isolated Neutrophils, In Vitro.
OBJECTIVE
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.
a Systems Design Engineering , University of Waterloo , Waterloo , Ontario , Canada.
Cameron
http://orcid.org/0000-0001-6512-5363
C
Postnikoff
a Systems Design Engineering , University of Waterloo , Waterloo , Ontario , Canada.|b School of Optometry and Vision Science , University of Waterloo , Waterloo , Ontario , Canada.
Maud
http://orcid.org/0000-0002-6731-2522
M
Gorbet
D002478:Cells, Cultured; D019573:Epithelium, Corneal / Q000166:cytology* / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D009504:Neutrophils / Q000166:cytology / Q000378:metabolism*; D013666:Tears / Q000737:chemistry*
Closed eye; corneal epithelial cells; flow cytometry; hypoxia; neutrophil; ocular surface; tear film