Purpose: To determine whether astrocytes from lamina cribrosa region are biochemically activated by peptide products of deiminated myelin basic protein (MBP), resulting in expression of immune molecules and thus imparting the capacity to present antigens to activate T cells.
Methods: We obtained deiminated and non-deiminated synthetic myelin basic protein peptides, and subjected isolated lamina cribrosa astrocytes obtained from C57BL/6J mice (about 3000 per plate for 24 hours) to biochemical stimulation with either deiminated or non-deiminated peptide (control). Astrocyte activation was measured by overexpression of morphological and other established activity markers such as ALDH1-L1, S-100β and Aquaporin 4.
Immunological activation was assessed in terms of expression of the co-stimulatory molecules B7-1 (CD80) and B7-2 (CD86), since these molecules are required for activation of naïve T-cells. MHC class I and II expression was examined upon priming of T-cells with non-activated and activated astrocytes. Animals were used adhering to ARVO statement for utilization of animals in vision research.
Results: Expression of co-stimulatory and MHC class II molecules was upregulated as detected by immunohistochemistry, ELISA and Western blot analyses in activated astrocytes but not in control (non-activated) astrocytes derived from C57BL/6J mice.
Conclusion: Biochemical stimulation of astrocytes by deiminated MBP peptides increases their immunologic activation and antigen presentation capacity to T cells.
