To identify any potential antigens that might have cross reactivity with normal tissue, they filtered the remaining tumour peptides against a database of MHC peptides on normal tissues, removing any peptide with a parent gene represented in normal tissue.
They subsequently prioritised peptides that were derived from genes essential to the tumour and had characteristics required to engage the immune system. In the study, detailed in Nature, the team stripped MHC molecules off neuroblastoma cells and determined which peptides were present and used a large genomic dataset to determine which peptides were unique to neuroblastoma and not expressed by normal tissues.
