Tear sialomucins

Thus the question to be addressed in this study was, whether a lectin histochemical study on human conjunctival goblet cells could help to explain the discrepancy regarding the assumed key importance of goblet cells for tear sialomucins and the lack of numerical goblet cell reduction in some Dry Eye patients. 

This study, the first in a series of investigations on goblet cells in different locations, has revealed overall differences in glycoprotein expression of human conjunctival goblet cells and especially sophisticated differences in their sialomucin expression. The obtained data are in accordance with statements in the literature that tear mucins are preferentially produced by the conjunctival goblet cells However, the above data appear to contradict reports in the literature which assume a sole production of tear sialomucins by the conjunctival goblet cells. 

Pflugfelder, S.C., et al. 2000. Detection of sialomucin complex (MUC4) in human ocular surface epithelium and tear fluid. Invest Ophthalmol Vis Sci 41 1316. 

Tears were polarographed for determination of protein directly in the Brdi6ka solution, and the results were evaluated by comparison with a calibration graph of sialomucin (233). Tears have a remarkable polarographic activity, as our experiments proved, so that an addition of 0.05 ml of tears to 4 ml of Co" solution produced an extremely high wave, about 50 xA/mm. ... 

Definitely the data is requesting the extention of tear analyses of different groups of patients by additional neuraminic acid specific lectins in conjunction with specific neuraminidase controls. The above described investigations and efforts must also be complemented in future by studies on the respective corneal sialomucin type receptors. It is postulated that this way a fingerprint like typization of Dry Eye patients in individuals could be achieved. 

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