Abstract
Purpose: :
A protective autoimmunity has been proposed to minimize injury to the optic nerve by reducing the secondary degeneration of neurons. This neuroprotective autoimmune response is suppressed by a subpopulation of regulatory T cells (Tregs) represented by CD4+CD25+ T cells. These cells express a specific transcription factor, Foxp3, required for their function and development. The aim of our study is to measure the levels of regulatory T–cells (CD4+CD25+) in patients affected by primary open–angle glaucoma(POAG) and age–matched controls.
Methods: :
Whole blood was obtained by 21 patients affected by POAG (mean age:73 yrs, range 54–82) and 20 age–matched controls (mean age: 72 yrs, range 61–83) with negative history for neurodegenerative, autoimmune diseases, cancer, viral infection. Flow cytometric analysis was used to determine the CD4+CD25+high lymphocyte population and in a second step in 6 cases (mean age=75 yrs) and 6 controls (mean age=68) it was similarly tested a more specific Treg marker (Foxp3).
Results: :
The percentage of Tregs was calculated over the total amount of CD3+CD4+. The median value of Tregs (%) in POAG patients was 10.79 and 7.41 in controls. The U Mann Whitney showed a highly significant difference (p<0.001) between the two groups. In the second set of data the median percentage of Foxp3+Tregs was 8.03 in patients and 5.36 in controls, confirming a highly significant difference (p=0.01).
Conclusions: :
Patients with POAG express a higher amount of Treg(CD4+CD25+) than age–matched controls.
Keywords: neuroprotection