The role of matrix metalloproteinase-9 and the tissue inhibitor of metalloproteinase — 1 in endogenous uveitis in children

Purpose: to determine the content of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinases — 1 (TIMP-1) in the tear and blood serum (BS) and to analyze how these parameters correlate with the clinical course of endogenous uveitis in children.Materials and methods. 131 eyes with uveitis of 74 patients aged 3 to 17 (mean age 10.57 ± 3.29 years) were examined. The content of MMP-9 was found in 281 samples of the tear and 48 samples of BS. The dynamics of MMP-9 in the tear was studied in 55 patients (100 eyes), in BS — in 9 children. The content of TIMP-1 was studied in 173 tear samples and 25 BS samples. The dynamics of TIMP-1 was studied in the tear of 31 patients (56 eyes). The concentration of MMP-9 and TIMP-1 was determined by enzyme immunoassay (ELISA) using the kits ELISA for MMP-9/ELISA for tissue metalloproteinase inhibitor 1 (Cloud clone corporation, USA).Results. The content of MMP-9 in the tear dropped compared to the control group (p = 0.09). The highest content of MMP-9 in panuveitis was found in the tear as compared to the anterior and intermediate uveitis (p = 0.01). The highest MMP-9 concentration was found in cases of 3rd degree of proliferation, in contrast to the 1st and 2nd degrees (p = 0.16). An increased content of TIMP-1 was found in the tear in subactive/intermediate uveitis in contrast to inactive uveitis (p=0.08). An imbalance of MMP-9 was revealed in relation to TIMP-1 in the tears. In the early postoperative period, an increase in the content of MMP-9 and a decrease in TIMP-1 in the tear returning to the initial level was noted, which corresponds to normal wound healing.Conclusion. An increase in the content of TIMP-1 in the tear is associated with subactive/intermediate uveitis. The content of MMP-9 in the tear correlates with the proliferative process stage. A higher MMP-9 content in the tear in panuveitis, in contrast to the anterior and intermediate uveitis is associated with the involvement of all sections of the choroid of the eye into the inflammatory process. The decrease in the content of MMP-9 in the tears is probably explained by the inhibitory effect of glucocorticosteroid (GCS) therapy.