PubMed ID: 17301119
Author(s): Schmidt JF, Agapova OA, Yang P, Kaufman PL, Hernandez MR. Expression of ephrinB1 and its receptor in glaucomatous optic neuropathy. Br J Ophthalmol. 2007 Sep;91(9):1219-24. Epub 2007 Feb 14. PMID 17301119
Journal: The British Journal Of Ophthalmology, Volume 91, Issue 9, Sep 2007
OBJECTIVE To determine ephrinB1, ephrinB2 and EphB1 expression in the optic nerve head (ONH) and retina of monkeys with glaucoma and in human ONH astrocytes.
METHODS Using immunohistochemistry, the localisation of ephrinB1, ephrinB2 and EphB1 was determined in the ONH and retina bilaterally in monkeys with monocular laser-induced glaucoma. RT-PCR, western blot and immunocytochemistry were used to study ephrinB1, ephrinB2 and EphB1 expression in cultured human ONH astrocytes from donors with and without glaucoma.
RESULTS There was an increase in ephrinB1 and EphB1 expression in mild to moderate glaucoma. In the ONH, both ephrinB1 and EphB1 were localised to astrocytes and EphB1 was also localised to lamina cribrosa cells and perivascular cells. In the retina, ephrinB1 localised to Muller cells and astrocytes, and EphB1 was found in retinal ganglion cells. In ONH astrocytes in humans with glaucoma, ephrinB1 and EphB1 were up-regulated but barely present in donors without glaucoma.
CONCLUSIONS Ephrins are activated in early and moderate glaucoma in the ONH and retina. We postulate that the up-regulation of Eph/ephrin pathway may play a protective role by limiting axonal damage and inflammatory cell invasion. Loss of ephrin signalling in advanced glaucoma may explain macrophage activation.