Abstract
Purpose: :
To determine whether ocular astrocytes can be immunologically activated when subjected to biochemical stimulation by the addition of intact or fragment myelin protein components.
Methods: :
Isolated astrocytes obtained from C57BL/6J mice (about 3000 per plate) were cultured and subjected to biochemical stimulation by the addition of a myelin basic protein (MBP) synthetic peptide or a mixture of proteolytic peptides derived from MBP. Due to limited number of lamina cribrosa (LC) astrocytes and optic nerve head astrocytes, most experiments were performed on cultured brain cortex astrocytes and a subset was repeated with LC astrocytes. Immunological activation was assessed by expression of co-stimulatory molecules B7-1 (CD80) and B7-2 (CD86) as well as expression of members of the TNFR superfamily that are also up-regulated on antigen presenting cells (APCs) and on T cells post-activation including 4-1BB (CD137) and 4-1BBL (CD137L).
Results: :
Expression of co-stimulatory molecules and members of the TNFR superfamily was upregulated as detected by immunohistochemistry and Western blot in activated astrocytes but not in control (non-activated) astrocytes derived from the brain cortex, lamina cribrosa and optic nerve head of C57BL/6J mice.
Conclusions: :
Biochemical stimulation of astrocytes can result in their immunologic activation as measured by immunohistochemistry and Western blot analysis.and may therefore enhance their antigen presentation capacity
Keywords: astrocyte • immunomodulation/immunoregulation • lamina cribrosa