Citrullinated epitopes as a cancer vaccine target

The post-translational conversion of arginine residues to citrulline by peptidylarginine deiminase (PAD) enzymes requires millimolar concentrations of calcium. This can occur during apoptosis leading to precipitation of proteins and stimulation of CD4 and antibody responses which are associated with autoimmune diseases such as rheumatoid arthritis (RA). Citrullination has also been shown to occur as a result of a degradation and recycling process called autophagy that is induced in stressed cells. As such autophagy and citrullination could be a method for alerting the immune response to any stressed cell including tumour cells. Peptide epitopes from these modified epitopes are presented on MHC-II and stimulate CD4 T cell responses. This project aims to further explore citrullinated epitopes as a cancer vaccine target.