Keratocyte apoptosis increases in human corneal allografts during immune-mediated graft rejection

摘要

The primary cause of corneal allograft failure is immune-mediated rejection.1 There are data indicating that corneal rejection is mediated, at least partly, by the apoptosis of keratocytes and endothelial cells in the early stages of the disease.2"4 There are currently very few data on the pathological mechanisms of graft rejection in patients and very few reports on the histopathology in human tissue.4We had the unique opportunity to analyse the role of apoptosis in corneal tissue originating from two patients (patients 1 and 2) with persistent corneal graft rejection, as characterised by active keratitic precipitates at the time of repeated kerato-plasty. Both patients underwent a first keratoplasty because of keratoconus and experienced an acute episode of immune-mediated graft rejection, which was initially treated with systemic and topical steroid therapy over a few weeks. Three corneal specimens served as controls; one specimen with pseudophakic corneal oedema (patient 3), one with primary acquired keratoconus (patient 4) and a graft with recurrent keratoconus (patient 5) without a history or evidence of immune-mediated rejection.