Purpose:
Corneal grafting is the most common and successful form of transplantation, however, 20% of patients will experience an episode of immunological rejection in the first ten years after grafting. If rejection episodes are treated promptly the rejection can be resolved. Many patients such as Keratoconus patients are classed as been at low risk of rejection and these patients will be monitored less closely. However, some Keratoconus patients will experience rejection. If these patients could be identified as high risk patients they would be monitored more closely and rejection episode identified and treated earlier preventing the lost of the grafted cornea. In this study we have used microarray technology to identify genes which are up and down regulated in corneal graft rejection
Methods:
We extracted mRNA from blood samples taken from corneal graft patients at the time of transplant rejection and patients with successful grafts. We then used plastic arrays to identify genes up and down regulated. These results were confirmed by real-time PCR in a large group of patients.
Results:
We found 15 genes up or down regulated by at least 3 fold during episode of corneal graft rejection. One gene in particular, RANTES was found to be down regulated in patients with Keratoconus that were experiencing an episode of rejection compared to Keratoconus patients with successful grafts (p=0.009). However no difference was seen between rejecters and non-rejecters for the high risk patients (Figure 1)
Conclusions:
RANTES expression levels may prove to be a good prognostic marker to identifying Keratoconus patients at high risk of corneal graft rejection allowing closer monitoring and earlier detection of graft rejection.
Keywords: transplantation • cornea: basic science • keratoconus