Immune cell discovery opens door to new powerful cancer therapies

Scientists at UCL have identified how a subset of immune cells are activated to kill cancerous cells, a finding in mice which could hold the key to new powerful therapies against cancer. This new study built on previous research*, also led by Professors Sergio Quezada and Karl Peggs (both UCL Cancer Institute), which found that following immunotherapy some CD4+ T cells, traditionally thought to be 'helper' and 'regulator' immune cells, become cytotoxic and directly engage with and kill cancer cells. Published in Immunity , scientists examined the molecular and cellular mechanisms underpinning this activity, as part of an experimental study of immunotherapy in mice, funded by Cancer Research UK. Researchers found that IL-2, a 'growth factor' for T cells and the 'transcription factor' Blimp-1 are responsible for initiating potent killer activity in CD4+ T cells within cancerous tumours. Co-lead author, Professor Sergio Quezada, (UCL Cancer Institute), said: "We knew these immune cells had the ability to proactively kill cancer cells with incredible potency, but to maximise their potential, we needed to know how this mechanism was activated. "Our discovery provides the evidence and rationale for utilising Blimp-1 to maximise the anti-tumour activity of CD4+ T cells. "Work is now underway in our lab to develop new personalised cell therapies where the activity of Blimp-1 can be maxed up to drive potent tumour control." T cells are a subset of lymphocytes (white blood cells), which play a key role in the body's immune response.