To investigate the effect of tear hyperosmolarity and signs of clinical ocular surface pathology upon conjunctival goblet cell population.
111 participants were assessed using tear osmolarity (TO) measurements and a comprehensive selection of clinical ophthalmic tests. The resultant clinical database was assessed for evidence of patterns of composite increasing pathology. The total, filled, and empty goblet cell numbers were measured: total number of goblet cells as per cytokeratin 7 (CK7) immunofluorescence and number of filled goblet cells as per periodic acid Schiff's reagent (PAS) or lectin Helix Pomatia Agglutin (HPA). Goblet cell profile was correlated with composite clinical pathological grades.
No significant correlation was found between TO and goblet cell number or function (as indicated by number of filled or unfilled goblet cells). Distinct composite clinical pathological groups 0-IV with increasing pathology were created based upon the frequency of positive pathological signs, which adhered to the Dry Eye Workshop (DEWs) purported mechanism. Only in grade IV was there significantly increased mean tear osmolarity of 344 mOsm/L (p<0.000) along with significantly decreased empty goblet cell number (CK7+ and HPA-) compared to filled (CK7+ and HPA+, p=0.000). When the number of filled goblet cells (PAS+) was analyzed there was significant increase in tear osmolarity for the two most severe grades; 3 and 4.
The goblet cell population does not appear to be affected by isolated tear hyperosmolarity. Hyperosmolarity when combined with other ocular surface pathology or inflammation alter the goblet cell population.
Invest Ophthalmol Vis Sci. 2011 Apr 25. [Epub ahead of print]
Moore JE, Vasey GT, Dartt DA, Mc Gilligan VE, Atkinson SD, Grills C, Lamey PJ, Leccisotti A, Frazer DG, Moore TC.
Centre for Molecular Biosciences, University of Ulster, Coleraine, BT52 1SA.