The mystery of why some corneal transplants are rejected is being tackled by the Department of Ophthalmology at the University of Manchester
The mystery of why some corneal transplants are rejected is being tackled by the Department of Ophthalmology at the University of Manchester, where researchers are using technologies developed by BD Biosciences to study gene expression patterns during corneal organ culture.
Donor corneas are stored in organ culture for two to four weeks prior to corneal transplantation.
According to Chantal Hillarby, honorary lecturer in ocular immunology, "about 30% of corneas do not thrive in culture and have to be thrown away.
And of those that are transplanted, about 5% are rejected.
In order to understand what's controlling this, we are trying to find out which genes are expressed by the cornea in culture.
The best method we found was BD Atlas arrays; we just probe the array and then three days later have our results." "The cornea is a difficult tissue to work with.
The samples are small and the cells we are interested in are just a monolayer on the inner side of the cornea, so there isn't really enough RNA to make a probe.
The BD Smart cDNA amplification kit allows us to amplify the RNA without changing the ratios of the different genes.
Another difficulty is that the cornea contains lots of proteoglycans which precipitate with the RNA.
BD Biosciences was very supportive throughout and by talking to customers in the USA was able to find the ideal RNA extraction kit for us to use." Now Dr Hillarby's main challenge is to make the best use of the data produced.
"We have picked out around a hundred genes from the BD Atlas array whose expression changes in culture, but so far we have only had time to work on a fraction of these genes.
Eventually we hope to be able to use gene therapy to improve both the quality of the culture corneas and the success rate of corneal transplantation."
