Correlation of tear inflammatory cytokines and matrix metalloproteinases with four dry eye diagnostic tests.
OBJECTIVE
Tear cytokines and matrix metalloproteinases (MMPs) can be extracted from the Schirmer strip. This study examined the extracted levels of tear cytokines and MMPs from Schirmer strips and potential correlation with Schirmer's test, tear breakup time (TBUT), tear osmolarity, and ocular surface disease index (OSDI).


METHODS
Thirty healthy volunteers were clinically evaluated for known methods to diagnose dry eye disease, including Schirmer's test, tear osmolarity, OSDI, and TBUT. Tears were collected by Schirmer strips and proteins were extracted from the Schirmer strip in 0.5 M NaCl with 0.5% Tween 20 and analyzed using multiplex assay kits to examine cytokines or MMPs. Calculated cytokine and MMP concentrations for all samples were sorted into groups according to a positive or negative for each of the above-cited four dry eye diagnostic tests, individually and in combination.


RESULTS
Five inflammatory cytokines (IL-1α, -1β, -6, -8, and TNF-α) and five MMPs (MMPs 1, 2, 7, 9, and 10) were extracted from clinical Schirmer strips. Schirmer strip measurement and tear osmolarity correlated well with increased concentrations of the inflammatory cytokines and MMPs, whereas TBUT and OSDI did not.


CONCLUSIONS
Both the Schirmer's test and tear osmolarity may be more relevant to the clinician in the diagnosis of ocular surface diseases with an increased level of inflammatory mediators.
Pharmaceutical R&D, Bausch & Lomb, Inc., Rochester, New York, USA.
Karl R
KR
VanDerMeid
Stephanie P
SP
Su
Keith W
KW
Ward
Jin-Zhong
JZ
Zhang
D000328:Adult; D000704:Analysis of Variance; D016207:Cytokines / Q000032:analysis* / Q000378:metabolism*; D003941:Diagnostic Techniques, Ophthalmological; D015352:Dry Eye Syndromes / Q000175:diagnosis* / Q000378:metabolism; D005136:Eye Proteins / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D020782:Matrix Metalloproteinases / Q000032:analysis*; D008875:Middle Aged; D009994:Osmolar Concentration; D011934:Reagent Strips; D013666:Tears / Q000378:metabolism*
D016207:Cytokines; D005136:Eye Proteins; D011934:Reagent Strips; C042434:tear proteins; D020782:Matrix Metalloproteinases