Abstract
Purpose:
Several cytokins, adhesion molecules and growth factors play key role in inflammatory processes of the eye. Quantitative changes of these factors are measurable of serum. In many cases changes in these patiens’ tears is presented. The essential role of vascular endothelial growth factor (VEGF) in the immunpathology of systemic sclerosis (SSc) is confirmed in blood serum previously. However, there have been no any other investigations according to VEGF level determination in tears of SSc patients. To determine VEGF and total protein levels in tears of SSc patients. We also aimed to define tear secretion velocity in these patients and correlated the levels with clinical signs and symptoms.
Methods:
Tear samples were collected from 43 SSc patients and 27 healthy controls using capillary micropipette, first without, then with stimulation. Tear collecting time was measured during tear secretion. Diluted samples were stored in polypropylene tubes at -80 °C until assessment. Total protein values were determined using the BCA Microplate method, and then VEGF levels were measured with R&D immunoassay kit. The protocol that was used in this study was in full compliance with good clinical practices, the Declaration of Helsinki (1996), and the guidelines of the Medical and Health Science Centre of the University of Debrecen.
Results:
Patients’ average tear secretion velocity was 4.53 µl/min (1.5-25.6). The average total protein value was 6.9 µg/µl (1.8-12.3) in case of basal tear secretion and 6.26 µg/µl (2.3-16.5) in tears collected after stimulation. In tears collected without stimulation the average VEGF level was 4.95 pg/µl (3.51-8.06) and 4.69 pg/µl (2.66-6.44) with stimulation. We measured 4.13 µg/µl (1.0-14.1) total protein and 6.15 pg/μl (3.84-12.3) VEGF level in tears of healthy controls.
Conclusions:
In patients with keratoconjunctivitis sicca, the most frequent ocular sign of SSc, tear secretion velocity was 67% of the controls’. Total protein values in patients were 42% higher than in healthy controls, it may mean that total protein production or since SSc patients have a decreased tear secretion velocity. The protein concentration is only increased because of the smaller tear volume. Though VEGF in tears of SSc patients is decreased with 20%, and did not change upon stimulation, it can be explained also with the decreased tear secretion of patients.
Keywords: 748 vascular endothelial growth factor •
432 autoimmune disease