Assessing the role of regulatory T cells in the development and progression of tumours.

The T cell receptor (TCR) repertoires of Tregs and Tconv cells within the MCA induced tumours were analysed. The TCR repertoires of Treg and Tconv cells were found to be largely distinct suggesting that conversion between these two T cell populations does not readily occur. However, it was found that tumour specific proliferation and survival of Treg cells may instead account for their accumulation in tumours. These studies indicate that identification of factors causing preferential proliferation and survival of Treg cells in tumours may enable the inhibition of their suppressive effects. The findings of this thesis are important for the rational design of cancer immunotherapeutic strategies